Instructional Course Lecture
Role of Fresh Osteochondral Allografts for Large Talar Osteochondral Lesions Abstract Christopher E. Gross, MD Samuel B. Adams, MD Mark E. Easley, MD James A. Nunley II, MD
Osteochondral lesions of the talus, large or small, present a challenge to the treating orthopaedic surgeon. These cartilage and bony defects can cause substantial pain and functional disability. Surgical treatment of small lesions of the talus has been thoroughly explored and includes retrograde drilling, arthroscopic débridement and marrow stimulation, osteochondral autografting from cartilage/bone unit harvested from the ipsilateral knee (mosaicplasty), and autologous chondrocyte implantation. Although each of these reparative, replacement, or regenerative techniques has various degrees of success, they may be insufficient for the treatment of large osteochondral lesions of the talus. Large-volume osteochondral lesions of the talus (.1.5 cm in diameter or area .150 mm2) often involve sizable portions of the weight-bearing section of the talar dome, medially or laterally. To properly treat these osteochondral lesions of the talus, a fresh structural osteochondral allograft is a viable treatment option.
L From the Medical University of South Carolina, Charleston, SC (Dr. Gross) and Duke University Medical Center, Durham, NC (Dr. Adams, Dr. Easley, and Dr. Nunley). This article, as well as other lectures presented at the Academy’s Annual Meeting, will be available in March 2016 in Instructional Course Lectures, Volume 65. J Am Acad Orthop Surg 2016;24: e9-e17 http://dx.doi.org/10.5435/ JAAOS-D-15-00302 Copyright 2015 by the American Academy of Orthopaedic Surgeons.
arge-volume osteochondral lesions of the talus (OLTs) (.1.5 cm in diameter or area .150 mm2) often involve sizable portions of the weight-bearing portion of the talar dome, medially or laterally. In addition, they frequently involve the shoulder of the talus. These lesions are difficult to treat with standard techniques. OLTs have a poor ability to heal spontaneously, likely because of the relative hypovascularity of the cartilage and a sparse population of chondrocyte progenitor cells. Often, the OLT has a cystic component that is relatively more formidable to treat than a solitary cartilaginous lesion because it needs both cartilage restoration and bony structural support. For these large OLTs, fresh structural
osteochondral implantation has been employed.
Clinical Evaluation Ankle pain carries a broad differential diagnosis (Table 1). The surgeon must first obtain a thorough history from the patient that includes any recent or remote history of trauma or chronic ankle instability and whether any surgical intervention has been undertaken about the ankle. Most OLTs can be attributed to a traumatic event; however, atraumatic lesions may occur in up to 24% of cases.1 OLTs are also more commonly seen in the second decade of life and in men (70%).2 The onset, duration, quality, and severity of the symptoms must be established.
January 2016, Vol 24, No 1
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
e9
Role of Fresh Osteochondral Allografts for Large Talar Osteochondral Lesions
Table 1 Differential Diagnosis of an Osteochondral Lesion of the Talus Stress fracture of the foot/ankle Ankle instability Ankle/subtalar arthritis Synovitis Injury to the syndesmosis Peroneal tendon pathology Bony or soft-tissue impingement
One must document all alleviating or exacerbating factors as well as prior treatment. Frequent symptoms include pain, clicking/ catching, stiffness, and pain about the ankle. Many patients may not be able to tolerate a full examination because of pain or stiffness, but it is imperative to obtain a functional baseline. The entire lower extremity should be examined in both weightbearing and non–weight-bearing postures because it is critical to assess for mechanical alignment. The physical examination must include range of motion about the ankle and subtalar joints along with a gait analysis. A gait assessment is also useful for establishing a baseline of function. When observing gait, one should concentrate on the patient’s posture, stride length, cadence, and walking speed and the duration of the walking cycle. 3 Ankle range of motion should be carefully measured to ensure that one is not
measuring compensatory motion from the Chopart joints; this motion should be compared to that of the contralateral side. Ankle stability, including the talar tilt and anterior drawer tests in plantar flexion and dorsiflexion, should be measured and compared to that of the opposite ankle.
Imaging Radiographic analysis of the patient should include weight-bearing views (AP, lateral, and mortise/oblique) of the ankle. Radiographs of hindfoot alignment and the foot should also be considered4 (Figure 1). These views will help to visualize early degenerative changes or any malalignment that needs to be taken into consideration for preoperative planning. Often, radiographs may not demonstrate pathology; however, they may detect a cystic component of the lesion if it is sufficiently large. CT or MRI should be used in a primary role in cases of equivocal radiographs or in a supplemental role in preoperative planning to evaluate the degree of bone loss, osteonecrosis, or subchondral cyst formation (Figures 2 and 3). MRI may help identify other bony or soft-tissue lesions; therefore, it should be obtained in a patient who has persistent ankle pain without any radiographic abnormality. No evidence supports the superiority of either CT or MRI in the setting
of normal radiographs and a suspicious clinical picture. In reviewing the sensitivity or specificity of CT, MRI, and arthroscopy, Verhagen et al5 reported no significant difference in the diagnosis of OLTs. On the contrary, in a series of 14 OLTs that were not apparent on plain radiography, CT identified 29% of these lesions, whereas MRI identified all of the lesions.6 In characterizing the OLT or in planning surgery, CT is useful in assessing the subchondral bone, although MRI is better at visualizing the articular surface. In addition, when an OLT is diagnosed on MRI, a CT may be useful in determining the appropriate treatment because estimation of the size and stage of the lesion can be obscured by bone marrow edema on MRI.7 However, MRI is 81% to 92% accurate in staging OLTs.7-9 The first widely used radiographic classification of OLTs was developed by Berndt and Harty10 in 1959 and subsequently modified (Table 2). As originally described, OLTs were grouped into four stages, but this classification failed to address any cystic component of the OLT. Stage V was added by Scranton and McDermott11 in 2001, and Raikin12 reported treatment of a stage VI lesion (.3,000 mm3). The Berndt and Harty system may have poor correlation with what is seen during arthroscopy. In a review of 24 arthroscopically examined OLTs, 50% of OLTs classified as stage IV
Dr. Adams or an immediate family member is a member of a speakers’ bureau or has made paid presentations on behalf of Harvest Technologies; serves as a paid consultant to or is an employee of Biomet, Medshape, Medtronic, Regeneration Technologies, and Stryker; and has stock or stock options held in Medshape. Dr. Easley or an immediate family member is a member of a speakers’ bureau or has made paid presentations on behalf of Stryker and Tornier; serves as a paid consultant to or is an employee of DT MedSurg, Exactech, SBI, Tornier, Stryker, and TriMed; serves as an unpaid consultant to Orthofix; has received research or institutional support from Acumed and TriMed; and serves as a board member, owner, officer, or committee member of the American Orthopaedic Foot and Ankle Society. Dr. Nunley or an immediate family member has received royalties from Wright Medical Technology; is a member of a speakers’ bureau or has made paid presentations on behalf of Orthofix; serves as a paid consultant to or is an employee of Exactech, DT MedSurg, Stryker, and Tornier; has stock or stock options held in Bristol-Myers Squibb, Merck, and Johnson & Johnson; and has received research or institutional support from the Orthopaedic Research and Education Foundation, Synthes, Integra LifeSciences, Breg, and Tornier. Neither Dr. Gross nor any immediate family member has received anything of value from or has stock or stock options held in a commercial company or institution related directly or indirectly to the subject of this article.
e10
Journal of the American Academy of Orthopaedic Surgeons
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
Christopher E. Gross, MD, et al
Figure 1
AP (A), mortise (B), and lateral (C) radiographs of a medial talar dome lesion of the left ankle.
(Berndt and Harty system) were found to have intact cartilage during arthroscopic visualization.13 The authors described an arthroscopic grading system based on visualization of the cartilage: grade I, intact, firm, shiny cartilage; grade II, intact but soft cartilage; grade III, frayed cartilage. Ferkel et al14 expanded on this classification system but did not address the subchondral bone. Although several authors have proposed CT or MRI classification schemes, their classifications are similar to those of the original Berndt and Harty system.6,14,15 Currently, it is unclear if any classification system is helpful in guiding the treating surgeon.
Nonsurgical Treatment Some authors recommend a trial of 3 to 6 months of nonsurgical management for all nondisplaced OLTs. 16-18 Nonsurgical therapies include analgesics, activity modification, and protected weight bearing (eg, non–weight-bearing cast, CAM boot, patellar tendon– bearing brace). However, because of a scarcity of quality literature, no recommendations can be made as to the weight-bearing status or appropriate time for and type
Figure 2
Coronal (A) and sagittal (B) CT scans demonstrating evidence of a medial talar dome osteochondral defect with cystic changes.
of immobilization that may be helpful.
Surgical Treatment Patient Selection Characteristics of the OLT, including undamaged versus disrupted articular surface, being displaced versus nondisplaced, and cystic versus noncystic, must be taken into account during surgical planning.19 The patient must understand the inherent risks in
receiving an allograft, including disease transmission and allograft rejection, although the actual chances of these occurring are minimal. In our practice, the indications for using a fresh allograft for an OLT include the following: a patient who has failed prior arthroscopic techniques or cartilage restoration, a large OLT that involves the shoulder region of the talus, an OLT with a large cystic component, and any lesion .1.5 cm 2 in diameter or with an area .150 mm 2.
January 2016, Vol 24, No 1
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
e11
Role of Fresh Osteochondral Allografts for Large Talar Osteochondral Lesions
donor talus preoperatively to confirm correct size.
Figure 3
Cartilage Viability
Coronal T1-weighted (A) and coronal T2-weighted (B) and sagittal (C) magnetic resonance images demonstrating evidence of medial talar dome osteochondral defect with reactive bone marrow edema and cystic changes.
Table 2 Modified Berndt and Harty10 Radiographic Classification of Osteochondral Lesion of the Talus Stage I II III IV V11 VI12
Radiographic Findings Focal subchondral bone compression Focal subchondral bone compression with partial cartilage detachment Focal subchondral bone compression with complete detachment Focal subchondral bone compression with complete detachment and displaced Cartilage cap intact, talar dome subchondral cyst Cystic lesions .3,000 mm3
To find an appropriate donor talus, the patient’s contralateral talus is used as a template and sized on CT. We attempt to match the size and shape of the allograft as closely as possible to the patient’s native anatomy. Specifications are then sent to an agency that obtains allograft tissues. We use osteochondral allografts obtained from US FDA-approved suppliers who comply with the guidelines of the American Association of Tissue Banks. Both the patient and the surgeon must be prepared to wait an unspecified amount of time and to have a flexible schedule once a graft is available.
e12
The donor talus is sterilely harvested within 24 hours of death. Next, the allograft undergoes disease testing and sterility culturing for approximately 2 weeks. During this time, the donor’s medical history is reviewed for factors, such as highrisk behavior, that may lead to an unacceptable graft. The graft is maintained at 2°C to 4°C. If the graft passes, it is then processed and is shipped, usually within 3 weeks. The graft typically arrives at the hospital in 1 day. One must ensure that the graft is from the proper laterality and that the articular cartilage has been left intact on the allograft talus. We typically obtain a radiograph of the
Allograft transplantation serves to prevent long-term joint degeneration by providing viable chondrocytes that have the ability to support themselves. We prefer to use fresh osteochondral grafts in lieu of fresh-frozen or frozen allografts because of the amount of fresh chondrocytes, although a recent systematic review20 of knee osteochondral allografts could not show a difference in failure rate or functional outcomes among the different procurement methods. In the knee literature, fresh osteochondral allografts have been shown to contain viable chondrocytes for up to 17 years after transplantation.21 However, Enneking and colleagues22,23 were unable to demonstrate viable chondrocytes 1 year after transplantation. In fact, there was histologic evidence of early cartilage damage in the Enneking series. Chondrocyte viability decreases with time in fresh allografts. At 4 weeks from harvesting, osteochondral allografts have a significant drop in viable chondrocytes, albeit by only 30% from the starting amount.24 Nonetheless, as soon as the allograft is made available, the transplantation should be scheduled. In the study by Williams et al,24 60 osteochondral plugs were harvested from 10 fresh human femoral condyles within 48 hours after the death of the donor. The plugs were stored at 4°C. These specimens were then analyzed at 1 day, 1 week, 2 weeks, and 4 weeks after harvest. Chondrocyte viability and viable cell density remained unchanged at up to 2 weeks. Proteoglycan synthesis remained unchanged until 2 weeks. No significant differences were detected in glycosaminoglycan content or compressive or tensile modulus at 4 weeks.
Journal of the American Academy of Orthopaedic Surgeons
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
Christopher E. Gross, MD, et al
Surgical Technique Approaches Most of the surgical techniques used for smaller OLTs require minimal arthroscopic access. However, when dealing with reconstructing larger portions of the talus, the articular surface must be accessed perpendicularly.12,25-28 Lesions of the anterior or posterior surface of the talus are most easily accessible with a standard anterior or posterior approach for ankle arthrotomy. Depending on the location of the lesion, the talus is either maximally plantar or dorsiflexed to allow excision of the lesion and allograft transplantation. However, when dealing with medial or lateral shoulder lesions, the surgeon needs to perform either a medial malleolar osteotomy or a lateral malleolar osteotomy/anterior talofibular ligament/calcaneofibular ligament release, respectively. Medial Approach Our preferred approach is the oblique medial malleolar osteotomy. One theoretical concern about this technique is that it breaches the articular surface of the tibial plafond; in practice, however, we have not experienced unexpected consequences, such as accelerated tibialsided arthritis. A 5-cm–long incision is made over the medial malleolus longitudinally. With careful soft-tissue dissection, the superficial neurovascular structures are protected. The posterior tibial tendon is exposed through the flexor retinaculum and protected. With fluoroscopic guidance, a guide pin or Kirschner wire (K-wire) is inserted, aimed obliquely through the medial malleolar shoulder to the lateral extent of the lesion. At this point, the holes for two 4.0-mm partially threaded cancellous screws are drilled. Then, with a saw, the osteotomy is made slightly distal and lateral to the K-wire path. Cold saline is used to mitigate the risk of heat necrosis.
Penetration into the articular surface is made with a controlled maneuver using an osteotome. The distal osteotomized medial malleolus is then reflected on a deltoid pedicle. Anterior Approach An incision is made 1 cm lateral to the anterior tibial spine and centered over the ankle. The incision should be approximately 6 cm long, two thirds of it proximal to the ankle joint and one third distal to the joint. During the initial incision, care is taken to protect the intermediate cutaneous branch of the superficial peroneal nerve and the anterior neurovascular bundle. The superficial surgical dissection begins by incising the fascia and identifying the plane between the extensor hallucis longus (EHL) and the anterior tibialis tendon (ATT). The EHL is identified distally; the retinaculum over the sheath is incised to allow retraction laterally. Alternatively, the ATT sheath can be incised and the tendon moved laterally. The anterior neurovascular bundle is deep to the EHL tendon distally and should be carefully retracted laterally. Typically, the ATT is maintained in its sheath and is retracted medially. The overlying soft tissue is incised to expose the anterior ankle joint capsule. The capsule is reflected medially and laterally. The talus is now fully exposed and visualized. Frequently, a pin distractor is placed (one 2.4-mm pin in the tibia and one 2.4mm pin in the talus) to enhance visualization. Lateral Approach If the talar lesion is lateral, a 6- to 7-cm standard lateral approach is used, centered over the fibula and directed toward the fourth metatarsal. The skin is incised and the subcutaneous tissue is carefully dissected. The inferior extensor retinaculum is identified for later use in the repair. A Freer retractor or hemostat is placed anterior between the capsule and the bone, defining the
Figure 4
Intraoperative photograph of the talus. Using a combination of a microsagittal and a reciprocating saw with cold irrigant, the necrotic section of the talus has been removed.
capsule. The anterior talofibular ligament is then incised, erring on the fibular side such that there is enough tissue to pull back up to the fibula for closure. Once this step is performed, the talus can be anteriorly translated for the reconstruction. The fibula is rarely osteotomized because so much of the lateral surface of the talus is visible once the lateral ligaments have been released. Structural Reconstruction Once the lesion is identified, one should correlate the preoperative imaging with intraoperative visualization of the osteochondral lesion to ensure that the lesion is appreciated three-dimensionally. One or two small K-wires are inserted anterior to posterior in the talus to act as a guide for removing the OLT. Fluoroscopic images should confirm that the guide pin will allow for complete excision of the OLT. Using a combination of a microsagittal and a reciprocating saw (with cold irrigant), the necrotic section of the talus is removed (Figure 4). The reciprocating saw is used to create a perfect vertical cut adjacent to the lesion in the talus. A cut is then made
January 2016, Vol 24, No 1
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
e13
Role of Fresh Osteochondral Allografts for Large Talar Osteochondral Lesions
Figure 5
Intraoperative photographs of the talus. Once an outline of the initial cuts is made (A), both the native talar defects (B) and the allograft talus (C) are measured again.
Figure 6
Intraoperative photograph demonstrating the final construct of a talar hemi-allograft fixated with one titanium screw.
perpendicularly approximately 1.5 to 2 cm below the height of the dome of the talus. Once the diseased bone and cartilage are removed, the dimensions of the defect are carefully measured with a caliper and ruler. On a sterile back table, the portion of the allograft talus that corresponds with the defect is carefully measured to match the excised talus. Once an outline of the initial cuts is made, both the native talar defects and the allograft talus are again measured (Figure 5). The allograft is then cut with a combination of saws. The structural allograft is thoroughly irrigated to reduce potential immunogenicity and
e14
then brought to the defect in the talus, where it is trialed. Additional contouring is usually necessary using a small rongeur or power burr. Once the allograft has acceptable contours, it can be slightly press-fit into the native talus. Radiographs are checked but may overexaggerate small incongruities. It is best to rely on visual inspection. If imperfections between the inferior surface of the graft-native interface exist, it is best to fill them with crushed cancellous chips. One or two 1.5-mm titanium screws can be used to supplement fixation. It is important that the screw heads be countersunk (Figure 6). The ankle is brought through dorsiflexion and plantar flexion to ensure that the graft fits dynamically and that no impingement exists. The interface between the graft and host is covered with a fibrin sealant. The ankle is then closed in the usual fashion. If the medial approach is used, the medial malleolus is anatomically reduced and the reduction is confirmed radiographically. Fixation is performed with two screws and, at times, supplemented with a buttress plate or transverse screw. If the lateral approach is used, the anterior talofibular ligament is anatomically reduced and fixated with one 3.5-mm suture anchor while the ankle is held in maximum dorsiflexion and eversion.
Postoperative Protocol After wound closure, the patient is placed in a bulky post-mold and sugar tong splint and made non–weight bearing. The patient is usually kept overnight for pain control. Two to 3 weeks postsurgery, the wound is inspected and sutures removed. Although early passive range of motion may be best for the survival of the cartilage,29 this must be balanced with the need for the osteotomy to heal. Therefore, we place the patient in a short leg, non–weight-bearing cast for 4 more weeks. We split the cast so that the top half may be removed and the patient can perform ankle range-of-motion exercises while lying supine. At 6 weeks, the cast is removed and the patient is placed into a CAM boot walker. The patient can initiate partial weight bearing and progress to weight bearing as tolerated at 10 to 12 weeks. At 3 months, the patient is allowed to participate in recumbent cycling and other nonimpact activities. At 6 months, the patient may begin more advanced activities.
Outcomes Few studies exist on osteochondral allografting for OLTs, and there is even less literature for larger OLTs. Gross et al30 studied nine patients
Journal of the American Academy of Orthopaedic Surgeons
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
Christopher E. Gross, MD, et al
treated with fresh osteochondral allograft transplantation. Preoperatively, the lesions were at least 1 cm in diameter, with a Berndt and Harty stage IV classification, although the mean defect size was not reported. Two thirds of the allografts remained in situ at a mean follow-up of 11 years (range, 4 to 19 years). The grafts in the remaining patients demonstrated radiographic and intraoperative evidence of resorption or fragmentation; all of these went on to ankle fusion. Raikin12 reported on six patients with bulk allografting of OLTs (average size, 4.38 cm3; range, 3.54 to 6.70 cm3); satisfactory results were reported in five of the patients at 23 months. Four patients underwent fresh-frozen osteochondral allografting, and the other two had fresh allograft transplantation. The allografts were fixed with headless dual-pitched screws. The one patient who subsequently underwent an ankle fusion had a preoperative CT scan that demonstrated graft incorporation. More recently, Raikin31 published a report on 15 patients with large, cystic OLTs with a mean size of 6.1 cm3 (range, 3 to 10 cm3). Surgery was performed through an anterior arthrotomy in 10 patients, medial malleolar osteotomy in 4, and distal fibular osteotomy in 1. At 54 months, 13 allografts remained in situ, with marked improvement in the American Orthopaedic Foot and Ankle Society (AOFAS) AnkleHindfoot score and visual analog pain score. Two patients underwent ankle arthrodesis, at 32 and 76 months. In a study of 12 ankles treated with osteochondral allografting, Görtz et al32 reported an 83% survival rate at 38 months. All patients had an anterior arthrotomy with temporary distraction. The average lesion size was 3.6 cm2. Radiographically, all patients demonstrated graft incorporation by 6 months. Of the two
failures, one patient underwent an ankle fusion, and the other went on to have a revision allograft, which at 7 years postoperatively, was functioning well. Based on the OlerudMolander Ankle Score, 50% of the surviving grafts had excellent or good outcomes. Hahn et al33 reported on 18 patients who underwent fresh talar allograft implantation. The mean anterior-posterior size of the defect was 1.9 cm (range, 1.0 to 2.5 cm), and the mean medial-lateral size, 1.4 cm (range, 1.0 to 2.0 cm). The fixation methods were bioabsorbable pins, dual-pitched screws, or a combination of the two. A calciumsulfate/demineralized bone matrix was used in 85% of patients and acted as a grout to fill in incongruences. Of the 13 patients who returned for follow-up (mean, 48 months), there was a 100% graft incorporation rate on plain radiographs and no failures. There was marked improvement between the patients’ preoperative and postoperative pain and activity abilities, as measured with the AOFAS Ankle-Hindfoot scores and Foot Function Index. El-Rashidy et al34 retrospectively reviewed 38 patients after fresh osteochondral allograft transplantation. Each ankle was arthroscopically inspected before the arthrotomy. The average lesion size was 1.5 cm2. An anterior cruciate ligament reamer was used to ream the OLT to bleeding subchondral bone (10 to 12 mm). At a mean 37-month follow-up, AOFAS Ankle-Hindfoot scores were markedly improved from 52 to 79 points. Per the authors’ protocol, the grafts were harvested from a similar anatomic location on the donor talus to match the anatomy of the recipient talus. Seven patients underwent secondary ankle arthroscopy (four for lateral impingement) that revealed four intact grafts, three loose grafts, one graft with a 5- to 6-mm area of denuded cartilage, and one graft with diffuse
cartilage loss. Of the four patients with failed grafts, two had an ankle arthroplasty, one had an ankle arthrodesis, and one had a bipolar total ankle allograft. Postoperative MRI was acquired for 15 of 28 patients at an average of 33 months postoperatively. Using the MRI stability criteria of De Smet et al,36 the stability at the allograft-host interface was assessed. Ten patients showed no signs of graft instability and had good or fair graft incorporation (defined as ingrowth of bone marrow on T1weighted MRI). Of note, only three patients had good graft incorporation. Only one patient had evidence of graft collapse/subsidence. Adams et al36 reported on eight talar shoulder lesions treated with fresh allograft transplantation. At 48 months, all grafts were still in place, and patients experienced improvements in pain and functional outcomes scoring (ie, AOFAS AnkleHindfoot scores, Lower Extremity Functional Scale, visual analog pain score, Short Musculoskeletal Function Assessment). However, half the patients required additional surgical procedures, including arthroscopic débridement, removal of medial malleolar hardware, revision medial malleolar osteotomy, and supramalleolar/calcaneal osteotomies for a varus ankle. At final follow-up, radiographs demonstrated no joint-space narrowing or graft subsidence, but 37.5% had joint degenerative changes. Three patients with medial shoulder grafts had partial lucency along the lateral interface of the host bone and allograft. These patients were asymptomatic. One patient had superior graft resorption and radiographic lucency along the lateral border of the allograft. Haene et al37 used fresh allograft in 17 uncontained, large OLTs. The mean volume of the lesions was 3,408 mm3. At final follow-up, 16 of 17 ankles underwent CT at an
January 2016, Vol 24, No 1
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
e15
Role of Fresh Osteochondral Allografts for Large Talar Osteochondral Lesions
average of 4.1 years after surgery. Grafts were not incorporated in two patients. There was an average of 0.5 mm of graft subsidence. Subchondral cysts and joint-space narrowing were seen in seven ankles. Four patients were asymptomatic. Two patients had their ankles fused, and one patient had persistent symptoms.
Summary The use of large osteochondral allografts to treat large symptomatic OLTs can be effective in providing pain relief and improved functionality in the midterm. As indications evolve and techniques mature, osteochondral transplantation may stave off ankle fusion or arthroplasty in many of these patients. Its use and success hinge on high-quality, thoughtful research in the future.
References Evidence-based Medicine: Levels of evidence are described in the table of contents. In this article, reference 5 is a level III study. References 1, 2, 4, 6-18, 20-22, 24-35, 37, and 38 are level IV studies. References 3, 19, and 23 are level V expert opinion. References printed in bold type are those published within the past 5 years. 1. Dragoni M, Bonasia DE, Amendola A: Osteochondral talar allograft for large osteochondral defects: Technique tip. Foot Ankle Int 2011;32(9):910-916. 2. Chew KT, Tay E, Wong YS: Osteochondral lesions of the talus. Ann Acad Med Singapore 2008;37(1):63-68. 3. Chambers HG, Sutherland DH: A practical guide to gait analysis. J Am Acad Orthop Surg 2002;10(3):222-231. 4. Reilingh ML, Beimers L, Tuijthof GJ, Stufkens SA, Maas M, van Dijk CN: Measuring hindfoot alignment radiographically: The long axial view is more reliable than the hindfoot alignment view. Skeletal Radiol 2010;39(11): 1103-1108.
e16
5. Verhagen RA, Maas M, Dijkgraaf MG, Tol JL, Krips R, van Dijk CN: Prospective study on diagnostic strategies in osteochondral lesions of the talus: Is MRI superior to helical CT? J Bone Joint Surg Br 2005;87(1):41-46. 6. Anderson IF, Crichton KJ, GrattanSmith T, Cooper RA, Brazier D: Osteochondral fractures of the dome of the talus. J Bone Joint Surg Am 1989;71(8): 1143-1152. 7. Lee KB, Bai LB, Park JG, Yoon TR: A comparison of arthroscopic and MRI findings in staging of osteochondral lesions of the talus. Knee Surg Sports Traumatol Arthrosc 2008;16(11): 1047-1051. 8. Dipaola JD, Nelson DW, Colville MR: Characterizing osteochondral lesions by magnetic resonance imaging. Arthroscopy 1991;7(1):101-104. 9. Mintz DN, Tashjian GS, Connell DA, Deland JT, O’Malley M, Potter HG: Osteochondral lesions of the talus: A new magnetic resonance grading system with arthroscopic correlation. Arthroscopy 2003;19(4):353-359. 10. Berndt AL, Harty M: Transchondral fractures (osteochondritis dissecans) of the talus. J Bone Joint Surg Am 1959;41: 988-1020. 11. Scranton PE Jr, McDermott JE: Treatment of type V osteochondral lesions of the talus with ipsilateral knee osteochondral autografts. Foot Ankle Int 2001;22(5): 380-384.
19. McGahan PJ, Pinney SJ: Current concept review: Osteochondral lesions of the talus. Foot Ankle Int 2010;31(1): 90-101. 20.
Chahal J, Gross AE, Gross C, et al: Outcomes of osteochondral allograft transplantation in the knee. Arthroscopy 2013;29(3):575-588.
21. Convery FR, Akeson WH, Amiel D, Meyers MH, Monosov A: Long-term survival of chondrocytes in an osteochondral articular cartilage allograft: A case report. J Bone Joint Surg Am 1996; 78(7):1082-1088. 22. Enneking WF, Campanacci DA: Retrieved human allografts: A clinicopathological study. J Bone Joint Surg Am 2001;83(7): 971-986. 23. Enneking WF, Mindell ER: Observations on massive retrieved human allografts. J Bone Joint Surg Am 1991;73(8): 1123-1142. 24. Williams SK, Amiel D, Ball ST, et al: Prolonged storage effects on the articular cartilage of fresh human osteochondral allografts. J Bone Joint Surg Am 2003;85 (11):2111-2120. 25. Brittberg M, Peterson L, SjögrenJansson E, Tallheden T, Lindahl A: Articular cartilage engineering with autologous chondrocyte transplantation: A review of recent developments. J Bone Joint Surg Am 2003;85(suppl 3): 109-115.
12. Raikin SM: Stage VI: Massive osteochondral defects of the talus. Foot Ankle Clin 2004;9(4):737-744, vi.
26. Giannini S, Buda R, Grigolo B, Vannini F: Autologous chondrocyte transplantation in osteochondral lesions of the ankle joint. Foot Ankle Int 2001;22(6): 513-517.
13. Pritsch M, Horoshovski H, Farine I: Arthroscopic treatment of osteochondral lesions of the talus. J Bone Joint Surg Am 1986;68(6):862-865.
27. Giannini S, Vannini F: Operative treatment of osteochondral lesions of the talar dome: Current concepts review. Foot Ankle Int 2004;25(3):168-175.
14. Ferkel RD, Zanotti RM, Komenda GA, et al: Arthroscopic treatment of chronic osteochondral lesions of the talus: Longterm results. Am J Sports Med 2008;36(9): 1750-1762.
28. Muir D, Saltzman CL, Tochigi Y, Amendola N: Talar dome access for osteochondral lesions. Am J Sports Med 2006;34(9):1457-1463.
15. Hepple S, Winson IG, Glew D: Osteochondral lesions of the talus: A revised classification. Foot Ankle Int 1999; 20(12):789-793. 16. Bauer M, Jonsson K, Lindén B: Osteochondritis dissecans of the ankle: A 20-year follow-up study. J Bone Joint Surg Br 1987;69(1):93-96. 17. McCullough CJ, Venugopal V: Osteochondritis dissecans of the talus: The natural history. Clin Orthop Relat Res 1979;144:264-268. 18. Pettine KA, Morrey BF: Osteochondral fractures of the talus: A long-term followup. J Bone Joint Surg Br 1987;69(1): 89-92.
29. Salter RB, Simmonds DF, Malcolm BW, Rumble EJ, MacMichael D, Clements ND: The biological effect of continuous passive motion on the healing of full-thickness defects in articular cartilage: An experimental investigation in the rabbit. J Bone Joint Surg Am 1980;62(8): 1232-1251. 30. Gross AE, Agnidis Z, Hutchison CR: Osteochondral defects of the talus treated with fresh osteochondral allograft transplantation. Foot Ankle Int 2001;22 (5):385-391. 31. Raikin SM: Fresh osteochondral allografts for large-volume cystic osteochondral defects of the talus. J Bone Joint Surg Am 2009;91(12): 2818-2826.
Journal of the American Academy of Orthopaedic Surgeons
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
Christopher E. Gross, MD, et al 32. Görtz S, De Young AJ, Bugbee WD: Fresh osteochondral allografting for osteochondral lesions of the talus. Foot Ankle Int 2010;31(4):283-290.
of osteochondral lesions of the talar shoulder treated with fresh osteochondral allograft transplantation. J Bone Joint Surg Am 2011;93(7): 648-654.
for the treatment of cartilage defects of the talus: A retrospective review. J Bone Joint Surg Am 2011;93(17):1634-1640.
33. Hahn DB, Aanstoos ME, Wilkins RM: Osteochondral lesions of the talus treated with fresh talar allografts. Foot Ankle Int 2010;31(4):277-282.
35. De Smet AA, Ilahi OA, Graf B: Reassessment of the MR criteria for stability of osteochondritis dissecans in the knee and ankle. Skeletal Radiol 1996;25(2): 159-163.
34. El-Rashidy H, Villacis D, Omar I, Kelikian AS: Fresh osteochondral allograft
36. Adams SB Jr, Viens NA, Easley ME, Stinnett SS, Nunley JA II: Midterm results
37.
Haene R, Qamirani E, Story RA, Pinsker E, Daniels TR: Intermediate outcomes of fresh talar osteochondral allografts for treatment of large osteochondral lesions of the talus. J Bone Joint Surg Am 2012;94(12): 1105-1110.
January 2016, Vol 24, No 1
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
e17
Role of Fresh Osteochondral Allografts for Large Talar Osteochondral Lesions Abstract Christopher E. Gross, MD Samuel B. Adams, MD Mark E. Easley, MD James A. Nunley II, MD
Osteochondral lesions of the talus, large or small, present a challenge to the treating orthopaedic surgeon. These cartilage and bony defects can cause substantial pain and functional disability. Surgical treatment of small lesions of the talus has been thoroughly explored and includes retrograde drilling, arthroscopic débridement and marrow stimulation, osteochondral autografting from cartilage/bone unit harvested from the ipsilateral knee (mosaicplasty), and autologous chondrocyte implantation. Although each of these reparative, replacement, or regenerative techniques has various degrees of success, they may be insufficient for the treatment of large osteochondral lesions of the talus. Large-volume osteochondral lesions of the talus (.1.5 cm in diameter or area .150 mm2) often involve sizable portions of the weight-bearing section of the talar dome, medially or laterally. To properly treat these osteochondral lesions of the talus, a fresh structural osteochondral allograft is a viable treatment option.
L From the Medical University of South Carolina, Charleston, SC (Dr. Gross) and Duke University Medical Center, Durham, NC (Dr. Adams, Dr. Easley, and Dr. Nunley). This article, as well as other lectures presented at the Academy’s Annual Meeting, will be available in March 2016 in Instructional Course Lectures, Volume 65. J Am Acad Orthop Surg 2016;24: e9-e17 http://dx.doi.org/10.5435/ JAAOS-D-15-00302 Copyright 2015 by the American Academy of Orthopaedic Surgeons.
arge-volume osteochondral lesions of the talus (OLTs) (.1.5 cm in diameter or area .150 mm2) often involve sizable portions of the weight-bearing portion of the talar dome, medially or laterally. In addition, they frequently involve the shoulder of the talus. These lesions are difficult to treat with standard techniques. OLTs have a poor ability to heal spontaneously, likely because of the relative hypovascularity of the cartilage and a sparse population of chondrocyte progenitor cells. Often, the OLT has a cystic component that is relatively more formidable to treat than a solitary cartilaginous lesion because it needs both cartilage restoration and bony structural support. For these large OLTs, fresh structural
osteochondral implantation has been employed.
Clinical Evaluation Ankle pain carries a broad differential diagnosis (Table 1). The surgeon must first obtain a thorough history from the patient that includes any recent or remote history of trauma or chronic ankle instability and whether any surgical intervention has been undertaken about the ankle. Most OLTs can be attributed to a traumatic event; however, atraumatic lesions may occur in up to 24% of cases.1 OLTs are also more commonly seen in the second decade of life and in men (70%).2 The onset, duration, quality, and severity of the symptoms must be established.
January 2016, Vol 24, No 1
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
e9
Role of Fresh Osteochondral Allografts for Large Talar Osteochondral Lesions
Table 1 Differential Diagnosis of an Osteochondral Lesion of the Talus Stress fracture of the foot/ankle Ankle instability Ankle/subtalar arthritis Synovitis Injury to the syndesmosis Peroneal tendon pathology Bony or soft-tissue impingement
One must document all alleviating or exacerbating factors as well as prior treatment. Frequent symptoms include pain, clicking/ catching, stiffness, and pain about the ankle. Many patients may not be able to tolerate a full examination because of pain or stiffness, but it is imperative to obtain a functional baseline. The entire lower extremity should be examined in both weightbearing and non–weight-bearing postures because it is critical to assess for mechanical alignment. The physical examination must include range of motion about the ankle and subtalar joints along with a gait analysis. A gait assessment is also useful for establishing a baseline of function. When observing gait, one should concentrate on the patient’s posture, stride length, cadence, and walking speed and the duration of the walking cycle. 3 Ankle range of motion should be carefully measured to ensure that one is not
measuring compensatory motion from the Chopart joints; this motion should be compared to that of the contralateral side. Ankle stability, including the talar tilt and anterior drawer tests in plantar flexion and dorsiflexion, should be measured and compared to that of the opposite ankle.
Imaging Radiographic analysis of the patient should include weight-bearing views (AP, lateral, and mortise/oblique) of the ankle. Radiographs of hindfoot alignment and the foot should also be considered4 (Figure 1). These views will help to visualize early degenerative changes or any malalignment that needs to be taken into consideration for preoperative planning. Often, radiographs may not demonstrate pathology; however, they may detect a cystic component of the lesion if it is sufficiently large. CT or MRI should be used in a primary role in cases of equivocal radiographs or in a supplemental role in preoperative planning to evaluate the degree of bone loss, osteonecrosis, or subchondral cyst formation (Figures 2 and 3). MRI may help identify other bony or soft-tissue lesions; therefore, it should be obtained in a patient who has persistent ankle pain without any radiographic abnormality. No evidence supports the superiority of either CT or MRI in the setting
of normal radiographs and a suspicious clinical picture. In reviewing the sensitivity or specificity of CT, MRI, and arthroscopy, Verhagen et al5 reported no significant difference in the diagnosis of OLTs. On the contrary, in a series of 14 OLTs that were not apparent on plain radiography, CT identified 29% of these lesions, whereas MRI identified all of the lesions.6 In characterizing the OLT or in planning surgery, CT is useful in assessing the subchondral bone, although MRI is better at visualizing the articular surface. In addition, when an OLT is diagnosed on MRI, a CT may be useful in determining the appropriate treatment because estimation of the size and stage of the lesion can be obscured by bone marrow edema on MRI.7 However, MRI is 81% to 92% accurate in staging OLTs.7-9 The first widely used radiographic classification of OLTs was developed by Berndt and Harty10 in 1959 and subsequently modified (Table 2). As originally described, OLTs were grouped into four stages, but this classification failed to address any cystic component of the OLT. Stage V was added by Scranton and McDermott11 in 2001, and Raikin12 reported treatment of a stage VI lesion (.3,000 mm3). The Berndt and Harty system may have poor correlation with what is seen during arthroscopy. In a review of 24 arthroscopically examined OLTs, 50% of OLTs classified as stage IV
Dr. Adams or an immediate family member is a member of a speakers’ bureau or has made paid presentations on behalf of Harvest Technologies; serves as a paid consultant to or is an employee of Biomet, Medshape, Medtronic, Regeneration Technologies, and Stryker; and has stock or stock options held in Medshape. Dr. Easley or an immediate family member is a member of a speakers’ bureau or has made paid presentations on behalf of Stryker and Tornier; serves as a paid consultant to or is an employee of DT MedSurg, Exactech, SBI, Tornier, Stryker, and TriMed; serves as an unpaid consultant to Orthofix; has received research or institutional support from Acumed and TriMed; and serves as a board member, owner, officer, or committee member of the American Orthopaedic Foot and Ankle Society. Dr. Nunley or an immediate family member has received royalties from Wright Medical Technology; is a member of a speakers’ bureau or has made paid presentations on behalf of Orthofix; serves as a paid consultant to or is an employee of Exactech, DT MedSurg, Stryker, and Tornier; has stock or stock options held in Bristol-Myers Squibb, Merck, and Johnson & Johnson; and has received research or institutional support from the Orthopaedic Research and Education Foundation, Synthes, Integra LifeSciences, Breg, and Tornier. Neither Dr. Gross nor any immediate family member has received anything of value from or has stock or stock options held in a commercial company or institution related directly or indirectly to the subject of this article.
e10
Journal of the American Academy of Orthopaedic Surgeons
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
Christopher E. Gross, MD, et al
Figure 1
AP (A), mortise (B), and lateral (C) radiographs of a medial talar dome lesion of the left ankle.
(Berndt and Harty system) were found to have intact cartilage during arthroscopic visualization.13 The authors described an arthroscopic grading system based on visualization of the cartilage: grade I, intact, firm, shiny cartilage; grade II, intact but soft cartilage; grade III, frayed cartilage. Ferkel et al14 expanded on this classification system but did not address the subchondral bone. Although several authors have proposed CT or MRI classification schemes, their classifications are similar to those of the original Berndt and Harty system.6,14,15 Currently, it is unclear if any classification system is helpful in guiding the treating surgeon.
Nonsurgical Treatment Some authors recommend a trial of 3 to 6 months of nonsurgical management for all nondisplaced OLTs. 16-18 Nonsurgical therapies include analgesics, activity modification, and protected weight bearing (eg, non–weight-bearing cast, CAM boot, patellar tendon– bearing brace). However, because of a scarcity of quality literature, no recommendations can be made as to the weight-bearing status or appropriate time for and type
Figure 2
Coronal (A) and sagittal (B) CT scans demonstrating evidence of a medial talar dome osteochondral defect with cystic changes.
of immobilization that may be helpful.
Surgical Treatment Patient Selection Characteristics of the OLT, including undamaged versus disrupted articular surface, being displaced versus nondisplaced, and cystic versus noncystic, must be taken into account during surgical planning.19 The patient must understand the inherent risks in
receiving an allograft, including disease transmission and allograft rejection, although the actual chances of these occurring are minimal. In our practice, the indications for using a fresh allograft for an OLT include the following: a patient who has failed prior arthroscopic techniques or cartilage restoration, a large OLT that involves the shoulder region of the talus, an OLT with a large cystic component, and any lesion .1.5 cm 2 in diameter or with an area .150 mm 2.
January 2016, Vol 24, No 1
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
e11
Role of Fresh Osteochondral Allografts for Large Talar Osteochondral Lesions
donor talus preoperatively to confirm correct size.
Figure 3
Cartilage Viability
Coronal T1-weighted (A) and coronal T2-weighted (B) and sagittal (C) magnetic resonance images demonstrating evidence of medial talar dome osteochondral defect with reactive bone marrow edema and cystic changes.
Table 2 Modified Berndt and Harty10 Radiographic Classification of Osteochondral Lesion of the Talus Stage I II III IV V11 VI12
Radiographic Findings Focal subchondral bone compression Focal subchondral bone compression with partial cartilage detachment Focal subchondral bone compression with complete detachment Focal subchondral bone compression with complete detachment and displaced Cartilage cap intact, talar dome subchondral cyst Cystic lesions .3,000 mm3
To find an appropriate donor talus, the patient’s contralateral talus is used as a template and sized on CT. We attempt to match the size and shape of the allograft as closely as possible to the patient’s native anatomy. Specifications are then sent to an agency that obtains allograft tissues. We use osteochondral allografts obtained from US FDA-approved suppliers who comply with the guidelines of the American Association of Tissue Banks. Both the patient and the surgeon must be prepared to wait an unspecified amount of time and to have a flexible schedule once a graft is available.
e12
The donor talus is sterilely harvested within 24 hours of death. Next, the allograft undergoes disease testing and sterility culturing for approximately 2 weeks. During this time, the donor’s medical history is reviewed for factors, such as highrisk behavior, that may lead to an unacceptable graft. The graft is maintained at 2°C to 4°C. If the graft passes, it is then processed and is shipped, usually within 3 weeks. The graft typically arrives at the hospital in 1 day. One must ensure that the graft is from the proper laterality and that the articular cartilage has been left intact on the allograft talus. We typically obtain a radiograph of the
Allograft transplantation serves to prevent long-term joint degeneration by providing viable chondrocytes that have the ability to support themselves. We prefer to use fresh osteochondral grafts in lieu of fresh-frozen or frozen allografts because of the amount of fresh chondrocytes, although a recent systematic review20 of knee osteochondral allografts could not show a difference in failure rate or functional outcomes among the different procurement methods. In the knee literature, fresh osteochondral allografts have been shown to contain viable chondrocytes for up to 17 years after transplantation.21 However, Enneking and colleagues22,23 were unable to demonstrate viable chondrocytes 1 year after transplantation. In fact, there was histologic evidence of early cartilage damage in the Enneking series. Chondrocyte viability decreases with time in fresh allografts. At 4 weeks from harvesting, osteochondral allografts have a significant drop in viable chondrocytes, albeit by only 30% from the starting amount.24 Nonetheless, as soon as the allograft is made available, the transplantation should be scheduled. In the study by Williams et al,24 60 osteochondral plugs were harvested from 10 fresh human femoral condyles within 48 hours after the death of the donor. The plugs were stored at 4°C. These specimens were then analyzed at 1 day, 1 week, 2 weeks, and 4 weeks after harvest. Chondrocyte viability and viable cell density remained unchanged at up to 2 weeks. Proteoglycan synthesis remained unchanged until 2 weeks. No significant differences were detected in glycosaminoglycan content or compressive or tensile modulus at 4 weeks.
Journal of the American Academy of Orthopaedic Surgeons
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
Christopher E. Gross, MD, et al
Surgical Technique Approaches Most of the surgical techniques used for smaller OLTs require minimal arthroscopic access. However, when dealing with reconstructing larger portions of the talus, the articular surface must be accessed perpendicularly.12,25-28 Lesions of the anterior or posterior surface of the talus are most easily accessible with a standard anterior or posterior approach for ankle arthrotomy. Depending on the location of the lesion, the talus is either maximally plantar or dorsiflexed to allow excision of the lesion and allograft transplantation. However, when dealing with medial or lateral shoulder lesions, the surgeon needs to perform either a medial malleolar osteotomy or a lateral malleolar osteotomy/anterior talofibular ligament/calcaneofibular ligament release, respectively. Medial Approach Our preferred approach is the oblique medial malleolar osteotomy. One theoretical concern about this technique is that it breaches the articular surface of the tibial plafond; in practice, however, we have not experienced unexpected consequences, such as accelerated tibialsided arthritis. A 5-cm–long incision is made over the medial malleolus longitudinally. With careful soft-tissue dissection, the superficial neurovascular structures are protected. The posterior tibial tendon is exposed through the flexor retinaculum and protected. With fluoroscopic guidance, a guide pin or Kirschner wire (K-wire) is inserted, aimed obliquely through the medial malleolar shoulder to the lateral extent of the lesion. At this point, the holes for two 4.0-mm partially threaded cancellous screws are drilled. Then, with a saw, the osteotomy is made slightly distal and lateral to the K-wire path. Cold saline is used to mitigate the risk of heat necrosis.
Penetration into the articular surface is made with a controlled maneuver using an osteotome. The distal osteotomized medial malleolus is then reflected on a deltoid pedicle. Anterior Approach An incision is made 1 cm lateral to the anterior tibial spine and centered over the ankle. The incision should be approximately 6 cm long, two thirds of it proximal to the ankle joint and one third distal to the joint. During the initial incision, care is taken to protect the intermediate cutaneous branch of the superficial peroneal nerve and the anterior neurovascular bundle. The superficial surgical dissection begins by incising the fascia and identifying the plane between the extensor hallucis longus (EHL) and the anterior tibialis tendon (ATT). The EHL is identified distally; the retinaculum over the sheath is incised to allow retraction laterally. Alternatively, the ATT sheath can be incised and the tendon moved laterally. The anterior neurovascular bundle is deep to the EHL tendon distally and should be carefully retracted laterally. Typically, the ATT is maintained in its sheath and is retracted medially. The overlying soft tissue is incised to expose the anterior ankle joint capsule. The capsule is reflected medially and laterally. The talus is now fully exposed and visualized. Frequently, a pin distractor is placed (one 2.4-mm pin in the tibia and one 2.4mm pin in the talus) to enhance visualization. Lateral Approach If the talar lesion is lateral, a 6- to 7-cm standard lateral approach is used, centered over the fibula and directed toward the fourth metatarsal. The skin is incised and the subcutaneous tissue is carefully dissected. The inferior extensor retinaculum is identified for later use in the repair. A Freer retractor or hemostat is placed anterior between the capsule and the bone, defining the
Figure 4
Intraoperative photograph of the talus. Using a combination of a microsagittal and a reciprocating saw with cold irrigant, the necrotic section of the talus has been removed.
capsule. The anterior talofibular ligament is then incised, erring on the fibular side such that there is enough tissue to pull back up to the fibula for closure. Once this step is performed, the talus can be anteriorly translated for the reconstruction. The fibula is rarely osteotomized because so much of the lateral surface of the talus is visible once the lateral ligaments have been released. Structural Reconstruction Once the lesion is identified, one should correlate the preoperative imaging with intraoperative visualization of the osteochondral lesion to ensure that the lesion is appreciated three-dimensionally. One or two small K-wires are inserted anterior to posterior in the talus to act as a guide for removing the OLT. Fluoroscopic images should confirm that the guide pin will allow for complete excision of the OLT. Using a combination of a microsagittal and a reciprocating saw (with cold irrigant), the necrotic section of the talus is removed (Figure 4). The reciprocating saw is used to create a perfect vertical cut adjacent to the lesion in the talus. A cut is then made
January 2016, Vol 24, No 1
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
e13
Role of Fresh Osteochondral Allografts for Large Talar Osteochondral Lesions
Figure 5
Intraoperative photographs of the talus. Once an outline of the initial cuts is made (A), both the native talar defects (B) and the allograft talus (C) are measured again.
Figure 6
Intraoperative photograph demonstrating the final construct of a talar hemi-allograft fixated with one titanium screw.
perpendicularly approximately 1.5 to 2 cm below the height of the dome of the talus. Once the diseased bone and cartilage are removed, the dimensions of the defect are carefully measured with a caliper and ruler. On a sterile back table, the portion of the allograft talus that corresponds with the defect is carefully measured to match the excised talus. Once an outline of the initial cuts is made, both the native talar defects and the allograft talus are again measured (Figure 5). The allograft is then cut with a combination of saws. The structural allograft is thoroughly irrigated to reduce potential immunogenicity and
e14
then brought to the defect in the talus, where it is trialed. Additional contouring is usually necessary using a small rongeur or power burr. Once the allograft has acceptable contours, it can be slightly press-fit into the native talus. Radiographs are checked but may overexaggerate small incongruities. It is best to rely on visual inspection. If imperfections between the inferior surface of the graft-native interface exist, it is best to fill them with crushed cancellous chips. One or two 1.5-mm titanium screws can be used to supplement fixation. It is important that the screw heads be countersunk (Figure 6). The ankle is brought through dorsiflexion and plantar flexion to ensure that the graft fits dynamically and that no impingement exists. The interface between the graft and host is covered with a fibrin sealant. The ankle is then closed in the usual fashion. If the medial approach is used, the medial malleolus is anatomically reduced and the reduction is confirmed radiographically. Fixation is performed with two screws and, at times, supplemented with a buttress plate or transverse screw. If the lateral approach is used, the anterior talofibular ligament is anatomically reduced and fixated with one 3.5-mm suture anchor while the ankle is held in maximum dorsiflexion and eversion.
Postoperative Protocol After wound closure, the patient is placed in a bulky post-mold and sugar tong splint and made non–weight bearing. The patient is usually kept overnight for pain control. Two to 3 weeks postsurgery, the wound is inspected and sutures removed. Although early passive range of motion may be best for the survival of the cartilage,29 this must be balanced with the need for the osteotomy to heal. Therefore, we place the patient in a short leg, non–weight-bearing cast for 4 more weeks. We split the cast so that the top half may be removed and the patient can perform ankle range-of-motion exercises while lying supine. At 6 weeks, the cast is removed and the patient is placed into a CAM boot walker. The patient can initiate partial weight bearing and progress to weight bearing as tolerated at 10 to 12 weeks. At 3 months, the patient is allowed to participate in recumbent cycling and other nonimpact activities. At 6 months, the patient may begin more advanced activities.
Outcomes Few studies exist on osteochondral allografting for OLTs, and there is even less literature for larger OLTs. Gross et al30 studied nine patients
Journal of the American Academy of Orthopaedic Surgeons
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
Christopher E. Gross, MD, et al
treated with fresh osteochondral allograft transplantation. Preoperatively, the lesions were at least 1 cm in diameter, with a Berndt and Harty stage IV classification, although the mean defect size was not reported. Two thirds of the allografts remained in situ at a mean follow-up of 11 years (range, 4 to 19 years). The grafts in the remaining patients demonstrated radiographic and intraoperative evidence of resorption or fragmentation; all of these went on to ankle fusion. Raikin12 reported on six patients with bulk allografting of OLTs (average size, 4.38 cm3; range, 3.54 to 6.70 cm3); satisfactory results were reported in five of the patients at 23 months. Four patients underwent fresh-frozen osteochondral allografting, and the other two had fresh allograft transplantation. The allografts were fixed with headless dual-pitched screws. The one patient who subsequently underwent an ankle fusion had a preoperative CT scan that demonstrated graft incorporation. More recently, Raikin31 published a report on 15 patients with large, cystic OLTs with a mean size of 6.1 cm3 (range, 3 to 10 cm3). Surgery was performed through an anterior arthrotomy in 10 patients, medial malleolar osteotomy in 4, and distal fibular osteotomy in 1. At 54 months, 13 allografts remained in situ, with marked improvement in the American Orthopaedic Foot and Ankle Society (AOFAS) AnkleHindfoot score and visual analog pain score. Two patients underwent ankle arthrodesis, at 32 and 76 months. In a study of 12 ankles treated with osteochondral allografting, Görtz et al32 reported an 83% survival rate at 38 months. All patients had an anterior arthrotomy with temporary distraction. The average lesion size was 3.6 cm2. Radiographically, all patients demonstrated graft incorporation by 6 months. Of the two
failures, one patient underwent an ankle fusion, and the other went on to have a revision allograft, which at 7 years postoperatively, was functioning well. Based on the OlerudMolander Ankle Score, 50% of the surviving grafts had excellent or good outcomes. Hahn et al33 reported on 18 patients who underwent fresh talar allograft implantation. The mean anterior-posterior size of the defect was 1.9 cm (range, 1.0 to 2.5 cm), and the mean medial-lateral size, 1.4 cm (range, 1.0 to 2.0 cm). The fixation methods were bioabsorbable pins, dual-pitched screws, or a combination of the two. A calciumsulfate/demineralized bone matrix was used in 85% of patients and acted as a grout to fill in incongruences. Of the 13 patients who returned for follow-up (mean, 48 months), there was a 100% graft incorporation rate on plain radiographs and no failures. There was marked improvement between the patients’ preoperative and postoperative pain and activity abilities, as measured with the AOFAS Ankle-Hindfoot scores and Foot Function Index. El-Rashidy et al34 retrospectively reviewed 38 patients after fresh osteochondral allograft transplantation. Each ankle was arthroscopically inspected before the arthrotomy. The average lesion size was 1.5 cm2. An anterior cruciate ligament reamer was used to ream the OLT to bleeding subchondral bone (10 to 12 mm). At a mean 37-month follow-up, AOFAS Ankle-Hindfoot scores were markedly improved from 52 to 79 points. Per the authors’ protocol, the grafts were harvested from a similar anatomic location on the donor talus to match the anatomy of the recipient talus. Seven patients underwent secondary ankle arthroscopy (four for lateral impingement) that revealed four intact grafts, three loose grafts, one graft with a 5- to 6-mm area of denuded cartilage, and one graft with diffuse
cartilage loss. Of the four patients with failed grafts, two had an ankle arthroplasty, one had an ankle arthrodesis, and one had a bipolar total ankle allograft. Postoperative MRI was acquired for 15 of 28 patients at an average of 33 months postoperatively. Using the MRI stability criteria of De Smet et al,36 the stability at the allograft-host interface was assessed. Ten patients showed no signs of graft instability and had good or fair graft incorporation (defined as ingrowth of bone marrow on T1weighted MRI). Of note, only three patients had good graft incorporation. Only one patient had evidence of graft collapse/subsidence. Adams et al36 reported on eight talar shoulder lesions treated with fresh allograft transplantation. At 48 months, all grafts were still in place, and patients experienced improvements in pain and functional outcomes scoring (ie, AOFAS AnkleHindfoot scores, Lower Extremity Functional Scale, visual analog pain score, Short Musculoskeletal Function Assessment). However, half the patients required additional surgical procedures, including arthroscopic débridement, removal of medial malleolar hardware, revision medial malleolar osteotomy, and supramalleolar/calcaneal osteotomies for a varus ankle. At final follow-up, radiographs demonstrated no joint-space narrowing or graft subsidence, but 37.5% had joint degenerative changes. Three patients with medial shoulder grafts had partial lucency along the lateral interface of the host bone and allograft. These patients were asymptomatic. One patient had superior graft resorption and radiographic lucency along the lateral border of the allograft. Haene et al37 used fresh allograft in 17 uncontained, large OLTs. The mean volume of the lesions was 3,408 mm3. At final follow-up, 16 of 17 ankles underwent CT at an
January 2016, Vol 24, No 1
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
e15
Role of Fresh Osteochondral Allografts for Large Talar Osteochondral Lesions
average of 4.1 years after surgery. Grafts were not incorporated in two patients. There was an average of 0.5 mm of graft subsidence. Subchondral cysts and joint-space narrowing were seen in seven ankles. Four patients were asymptomatic. Two patients had their ankles fused, and one patient had persistent symptoms.
Summary The use of large osteochondral allografts to treat large symptomatic OLTs can be effective in providing pain relief and improved functionality in the midterm. As indications evolve and techniques mature, osteochondral transplantation may stave off ankle fusion or arthroplasty in many of these patients. Its use and success hinge on high-quality, thoughtful research in the future.
References Evidence-based Medicine: Levels of evidence are described in the table of contents. In this article, reference 5 is a level III study. References 1, 2, 4, 6-18, 20-22, 24-35, 37, and 38 are level IV studies. References 3, 19, and 23 are level V expert opinion. References printed in bold type are those published within the past 5 years. 1. Dragoni M, Bonasia DE, Amendola A: Osteochondral talar allograft for large osteochondral defects: Technique tip. Foot Ankle Int 2011;32(9):910-916. 2. Chew KT, Tay E, Wong YS: Osteochondral lesions of the talus. Ann Acad Med Singapore 2008;37(1):63-68. 3. Chambers HG, Sutherland DH: A practical guide to gait analysis. J Am Acad Orthop Surg 2002;10(3):222-231. 4. Reilingh ML, Beimers L, Tuijthof GJ, Stufkens SA, Maas M, van Dijk CN: Measuring hindfoot alignment radiographically: The long axial view is more reliable than the hindfoot alignment view. Skeletal Radiol 2010;39(11): 1103-1108.
e16
5. Verhagen RA, Maas M, Dijkgraaf MG, Tol JL, Krips R, van Dijk CN: Prospective study on diagnostic strategies in osteochondral lesions of the talus: Is MRI superior to helical CT? J Bone Joint Surg Br 2005;87(1):41-46. 6. Anderson IF, Crichton KJ, GrattanSmith T, Cooper RA, Brazier D: Osteochondral fractures of the dome of the talus. J Bone Joint Surg Am 1989;71(8): 1143-1152. 7. Lee KB, Bai LB, Park JG, Yoon TR: A comparison of arthroscopic and MRI findings in staging of osteochondral lesions of the talus. Knee Surg Sports Traumatol Arthrosc 2008;16(11): 1047-1051. 8. Dipaola JD, Nelson DW, Colville MR: Characterizing osteochondral lesions by magnetic resonance imaging. Arthroscopy 1991;7(1):101-104. 9. Mintz DN, Tashjian GS, Connell DA, Deland JT, O’Malley M, Potter HG: Osteochondral lesions of the talus: A new magnetic resonance grading system with arthroscopic correlation. Arthroscopy 2003;19(4):353-359. 10. Berndt AL, Harty M: Transchondral fractures (osteochondritis dissecans) of the talus. J Bone Joint Surg Am 1959;41: 988-1020. 11. Scranton PE Jr, McDermott JE: Treatment of type V osteochondral lesions of the talus with ipsilateral knee osteochondral autografts. Foot Ankle Int 2001;22(5): 380-384.
19. McGahan PJ, Pinney SJ: Current concept review: Osteochondral lesions of the talus. Foot Ankle Int 2010;31(1): 90-101. 20.
Chahal J, Gross AE, Gross C, et al: Outcomes of osteochondral allograft transplantation in the knee. Arthroscopy 2013;29(3):575-588.
21. Convery FR, Akeson WH, Amiel D, Meyers MH, Monosov A: Long-term survival of chondrocytes in an osteochondral articular cartilage allograft: A case report. J Bone Joint Surg Am 1996; 78(7):1082-1088. 22. Enneking WF, Campanacci DA: Retrieved human allografts: A clinicopathological study. J Bone Joint Surg Am 2001;83(7): 971-986. 23. Enneking WF, Mindell ER: Observations on massive retrieved human allografts. J Bone Joint Surg Am 1991;73(8): 1123-1142. 24. Williams SK, Amiel D, Ball ST, et al: Prolonged storage effects on the articular cartilage of fresh human osteochondral allografts. J Bone Joint Surg Am 2003;85 (11):2111-2120. 25. Brittberg M, Peterson L, SjögrenJansson E, Tallheden T, Lindahl A: Articular cartilage engineering with autologous chondrocyte transplantation: A review of recent developments. J Bone Joint Surg Am 2003;85(suppl 3): 109-115.
12. Raikin SM: Stage VI: Massive osteochondral defects of the talus. Foot Ankle Clin 2004;9(4):737-744, vi.
26. Giannini S, Buda R, Grigolo B, Vannini F: Autologous chondrocyte transplantation in osteochondral lesions of the ankle joint. Foot Ankle Int 2001;22(6): 513-517.
13. Pritsch M, Horoshovski H, Farine I: Arthroscopic treatment of osteochondral lesions of the talus. J Bone Joint Surg Am 1986;68(6):862-865.
27. Giannini S, Vannini F: Operative treatment of osteochondral lesions of the talar dome: Current concepts review. Foot Ankle Int 2004;25(3):168-175.
14. Ferkel RD, Zanotti RM, Komenda GA, et al: Arthroscopic treatment of chronic osteochondral lesions of the talus: Longterm results. Am J Sports Med 2008;36(9): 1750-1762.
28. Muir D, Saltzman CL, Tochigi Y, Amendola N: Talar dome access for osteochondral lesions. Am J Sports Med 2006;34(9):1457-1463.
15. Hepple S, Winson IG, Glew D: Osteochondral lesions of the talus: A revised classification. Foot Ankle Int 1999; 20(12):789-793. 16. Bauer M, Jonsson K, Lindén B: Osteochondritis dissecans of the ankle: A 20-year follow-up study. J Bone Joint Surg Br 1987;69(1):93-96. 17. McCullough CJ, Venugopal V: Osteochondritis dissecans of the talus: The natural history. Clin Orthop Relat Res 1979;144:264-268. 18. Pettine KA, Morrey BF: Osteochondral fractures of the talus: A long-term followup. J Bone Joint Surg Br 1987;69(1): 89-92.
29. Salter RB, Simmonds DF, Malcolm BW, Rumble EJ, MacMichael D, Clements ND: The biological effect of continuous passive motion on the healing of full-thickness defects in articular cartilage: An experimental investigation in the rabbit. J Bone Joint Surg Am 1980;62(8): 1232-1251. 30. Gross AE, Agnidis Z, Hutchison CR: Osteochondral defects of the talus treated with fresh osteochondral allograft transplantation. Foot Ankle Int 2001;22 (5):385-391. 31. Raikin SM: Fresh osteochondral allografts for large-volume cystic osteochondral defects of the talus. J Bone Joint Surg Am 2009;91(12): 2818-2826.
Journal of the American Academy of Orthopaedic Surgeons
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
Christopher E. Gross, MD, et al 32. Görtz S, De Young AJ, Bugbee WD: Fresh osteochondral allografting for osteochondral lesions of the talus. Foot Ankle Int 2010;31(4):283-290.
of osteochondral lesions of the talar shoulder treated with fresh osteochondral allograft transplantation. J Bone Joint Surg Am 2011;93(7): 648-654.
for the treatment of cartilage defects of the talus: A retrospective review. J Bone Joint Surg Am 2011;93(17):1634-1640.
33. Hahn DB, Aanstoos ME, Wilkins RM: Osteochondral lesions of the talus treated with fresh talar allografts. Foot Ankle Int 2010;31(4):277-282.
35. De Smet AA, Ilahi OA, Graf B: Reassessment of the MR criteria for stability of osteochondritis dissecans in the knee and ankle. Skeletal Radiol 1996;25(2): 159-163.
34. El-Rashidy H, Villacis D, Omar I, Kelikian AS: Fresh osteochondral allograft
36. Adams SB Jr, Viens NA, Easley ME, Stinnett SS, Nunley JA II: Midterm results
37.
Haene R, Qamirani E, Story RA, Pinsker E, Daniels TR: Intermediate outcomes of fresh talar osteochondral allografts for treatment of large osteochondral lesions of the talus. J Bone Joint Surg Am 2012;94(12): 1105-1110.
January 2016, Vol 24, No 1
Copyright ª the American Academy of Orthopaedic Surgeons. Unauthorized reproduction of this article is prohibited.
e17
