Fresh Osteochondral Allograft Transplantation for Bipolar Reciprocal Osteochondral Lesions of the Knee Gokhan Meric,*y MD, Guilherme C. Gracitelli,*z MD, Simon Go¨rtz,§ MD, Allison J. De Young,* MPA, PA-C, and William D. Bugbee,||{ MD Investigation performed at Scripps Clinic, La Jolla, California, USA Background: Osteochondral allograft (OCA) transplantation is an effective treatment option for chondral and osteochondral defects of the knee. Hypothesis: Patients treated with OCAs for reciprocal bipolar lesions of the knee would demonstrate significant clinical improvement. Study Design: Case series; Level of evidence, 4. Methods: Between 1983 and 2010, OCAs were implanted for bipolar chondral lesions in 46 patients (48 knees). The 21 male and 25 female patients averaged 40 years of age (range, 15-66 years). Thirty-four lesions were tibiofemoral, and 14 were patellofemoral. Forty-two knees (88%) had undergone a mean of 3.4 previous surgeries (range, 1-8). The mean allograft area was 19.2 cm2. Clinical evaluation included the modified Merle d’Aubigne´-Postel (18-point), International Knee Documentation Committee (IKDC) pain and function, and Knee Society function (KS-F) scores. Further surgeries on the operative joint were documented. Results: Survivorship of the bipolar OCA was 64.1% at 5 years. Thirty knees underwent further surgery; 22 knees (46%) were considered failures (3 OCA revisions, 14 total knee arthroplasties, 2 unicondylar arthroplasties, 2 arthrodeses, and 1 patellectomy). Among patients whose OCA was still in situ at follow-up, the mean follow-up was 7 years (range, 2.0-19.7 years). The mean 18-point score improved from 12.1 to 16.1; 88% (23/26 knees) of surviving allografts scored 15. The mean IKDC pain score improved from 7.5 to 4.7, and the mean IKDC function score improved from 3.4 to 7.0. The mean KS-F score improved from 70.5 to 84.1. Conclusion: Osteochondral allograft transplantation is a useful salvage treatment option for reciprocal bipolar cartilage lesions of the knee. High reoperation and failure rates were observed, but patients with surviving allografts showed significant clinical improvement. Keywords: knee; cartilage; osteochondral allograft; osteochondral defect; osteochondral transplantation
Chondral lesions in the knee are common and potentially debilitating problems. Large or complex chondral or osteochondral lesions in particular present a difficult clinical challenge with few restorative treatment options.1 Although microfracture, osteochondral autologous transfer (OAT), and autologous chondrocyte implantation (ACI) are procedures used for cartilage lesions, their application and effectiveness decline in direct correlation to increasing lesion size and/or as a result of previously failed surgery.10,13,25 Failure is more common for bipolar, reciprocal (‘‘kissing’’) chondral lesions with or without osseous or meniscal deficiency, which constitutes a relative contraindication to these particular cartilage repair procedures.23 If not adequately treated, reciprocal lesions frequently
progress to advanced osteoarthritis, usually relegating patients to partial or total joint arthroplasty.8,27,31 Osteochondral allograft (OCA) transplantation has been recommended in recent treatment algorithms for the reconstruction of large osteochondral defects of the knee.24,32 OCA transplantation is especially utilized in active, young patients with cartilage defects in whom previous treatment procedures have failed. The fundamental principle of allografting is the replacement of injured or diseased articular cartilage and underlying bone with an orthotopic, allogenic transplant consisting of mature hyaline cartilage containing viable chondrocytes along with underlying supporting subchondral bone. The only technique that treats cartilage defects with anatomically matched hyaline cartilage, OCA transplantation has the advantage of no donor site morbidity for patients and a minor immunological response.18 A number of authors have reported on the outcome of OCAs.3-5,9,15,18 The purpose of this study was to evaluate the outcomes of patients
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TABLE 1 Demographic and Cartilage Lesion Informationa Demographics Age, mean (range), y Male/female sex, n BMI, mean (range), kg/m2 Diagnosis, n (%) TCI OA DCL Failed OCA Other (OCD, chronic subluxation, and plateau fracture) Location of the graft, n (%) Lateral tibiofemoral joint Medial tibiofemoral joint Patellofemoral joint Type of previous surgeries, n (%) Partial or total meniscectomy Ligament surgery Chondral debridement Loose body removal Subchondral marrow stimulation OAT OCA
40 (15-66) 21/25 26.8 (19.2-38.5) 25 9 9 2 3
(52.1) (18.8) (18.8) (4.2) (6.3)
20 (42) 14 (29) 14 (29) 23 7 34 7 6 1 2
(47) (14) (70) (14) (12) (2) (4)
a BMI, body mass index; DCL, degenerative chondral lesion; OA, osteoarthritis; OAT, osteochondral autologous transfer; OCA, osteochondral allograft; OCD, osteochondritis dissecans; TCI, traumatic chondral injury.
who had undergone OCA transplantation for reciprocal bipolar cartilage injuries (‘‘kissing lesions’’) of the knee.
MATERIALS AND METHODS We retrospectively identified 51 patients (53 knees) who had undergone OCA transplantation for bipolar cartilage lesions of the knee from 1983 to 2010 in an institutional review board–approved clinical database. Of the 51 patients, 5 were lost to follow-up before 2 years. Index demographic details were collected on the remaining 46 patients (48 knees) included in this study. Forty-two of the 48 (88%) knees had undergone a combined 143 previous surgeries, with a mean of 3.4 surgeries (range, 1-8). The remaining 6 knees had undergone no prior surgery. The demographic and cartilage lesion information are detailed in Table 1. The indications of this surgery were reciprocal lesions in the patellofemoral joint and tibiofemoral joint, International
Figure 1. Preoperative (A) anteroposterior and (B) lateral radiographs of a 47-year-old male show signs of right lateral compartment loss of joint space. The patient had undergone lateral meniscectomy.
Cartilage Repair Society (ICRS) grades 3 and 4, and patients who had failed previous surgical and nonsurgical interventions and/or wished to avoid prosthetic arthroplasty. Demographic, pain, and joint function data were obtained preoperatively. Donors and recipients were matched based on size using standard radiographs corrected for magnification (Figure 1). No blood or tissue typing was performed, and no immunosuppressive therapy was used.5 We obtained fresh anatomically appropriate tissue from healthy donors who met the criteria of the American Association of Tissue Banks.26 Donor tissue was recovered within 24 hours of donor death, processed, and maintained fresh at 4°C until the time of implantation, which was between 3 and 28 days from tissue recovery. The senior author (W.D.B.) performed the majority of the procedures. Surgeries were performed with the patient in a supine position under tourniquet control using full arthrotomy or miniarthrotomy through a midline incision as previously described.14 The osteoarticular lesions were identified depending on topographic characteristics (Figure 2), including affected compartment, lesion size, and location. An instrumented dowel or a freehand (shell) technique was selected. Tibial grafts consisted of hemitibial plateaus transplanted with their attached meniscus as a compound graft in cases of associated meniscal insufficiency. Patellar grafts consisted of whole surface shell grafts and then either complete corresponding trochlear groove shell grafts or focal trochlear allograft plugs. We prepared graft beds down to healthy bleeding bone using standard instruments and techniques. We tailored the grafts to orthotopically match the prepared lesion. We
{ Address correspondence to William D. Bugbee, MD, Division of Orthopaedic Surgery, Scripps Clinic, 10666 North Torrey Pines Road, MS 116, La Jolla, CA 92037, USA (e-mail: [email protected]). *Shiley Center for Orthopaedic Research and Education, Scripps Clinic, La Jolla, California, USA. y Department of Orthopaedic Surgery, Balikesir University, Balikesir, Turkey. z Department of Orthopaedic Surgery, Federal University of Sa˜o Paulo, Sa˜o Paulo, Brazil. § Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, California, USA. || Division of Orthopaedic Surgery, Scripps Clinic, La Jolla, California, USA. One or more of the authors has declared the following potential conflict of interest or source of funding: W.D.B. is a consultant for and has received research support from the Joint Restoration Foundation, a nonprofit tissue bank that receives, processes, and distributes osteochondral allografts. G.M. was supported by The Scientific and Technological Research Council of Turkey (TUBITAK) (Ref: B.14.2.TBT.0.06.01-219-6040). G.C.G. was supported by Coordination for the Improvement of Higher Education Personnel (CAPES) of Brazil.
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Figure 2. Intraoperative Intraoperative image showing reciprocal bipolar articular cartilage disease with ‘‘kissing lesions’’ in the area of prior surgery and loss of the lateral meniscus in the right knee. then performed trial fittings after the grafts were copiously pulse lavaged to remove debris and marrow elements to decrease the immunogenicity of the graft. Grafts were properly positioned, and an acceptable press fit was achieved. In patients with inadequate press-fit stability, we supplemented fixation using absorbable pins (OrthoSorb; DePuy Synthes) (Figure 3). On the tibial side, we stabilized using a cannulated interfragmentary compression screw (Figures 3 and 4). On an intraoperative worksheet, we documented details regarding the procedure, including the size and location of each allograft. Thirty-four OCA procedures involved the tibiofemoral joint (20 lateral and 14 medial compartments); 14 involved the patellofemoral joint. The mean graft area for the entire group was 19.2 cm2 (range, 4.2-41.0 cm2). Twenty-two knees underwent concomitant procedures at the time of OCA transplantation. Some knees had more than 1 concomitant procedure. We performed 9 hardware removals, 7 retinacular releases (6 lateral, 1 medial), 2 meniscectomies, 2 debridements, 2 anterior cruciate ligament reconstructions, 1 lateral imbrication, 1 high tibial osteotomy (HTO), and 1 distal femoral osteotomy (DFO). Of the 34 knees that underwent tibiofemoral osteochondral allografting, 18 had a meniscal allograft (10 lateral, 8 medial). Two patients had staged bilateral allograft procedures performed at 14 months and at 96 months. Postoperatively, tibiofemoral grafts were protected with a range of motion brace, whereas patellofemoral grafts were braced in extension, limiting range of motion from full extension to 30° to avoid the patella engaging the trochlea. Postoperative care included routine physical therapy with protected weightbearing up to 3 months. Return to daily activity usually was allowed after 4 months. Closed chain exercises were started at 4 weeks and unrestricted activities of daily living at 3 to 4 months. Preoperative and postoperative clinical evaluations included the International Knee Documentation Committee
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Figure 3. Intraoperative image of a right lateral tibiofemoral bipolar compound allograft with the compound meniscus in situ after fixation with bioabsorbable chondral darts and compression screws.
Figure 4. (A) Anteroposterior weightbearing and (B) lateral radiographs show the patient 44 months after lateral bipolar tibiofemoral and meniscal allografting. (IKDC) questionnaire to measure patients’ self-reported pain and function using a visual analog scale format,20 the Knee Society function (KS-F) score,19 and the modified Merle d’Aubigne´-Postel (18-point) scale.7 Additional surgeries performed on the operative joint were documented at latest follow-up. Revision allografting, conversion to arthroplasty, arthrodesis, and patellectomy were considered failures. We assessed satisfaction with the procedure at each patient’s latest follow-up using a questionnaire, which included the following: patients’ satisfaction with the results of the surgery (5 = extremely satisfied, 1 = extremely dissatisfied), pain and function in comparison to preoperative status (better, same, worse), and whether the patient would undergo the same surgery again under similar circumstances. Patients unable to return for clinical evaluation were contacted by telephone. We analyzed preoperative and postoperative IKDC pain and function scores, KS-F scores, and 18-point scores using nonparametric Wilcoxon signed-rank tests. Survivorship
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TABLE 2 Reoperations After Allograft Surgery Procedure
n
Arthroscopic debridement Distal femoral osteotomy Hardware removal Repeat allografting Converted to arthrodesis after infection Patellectomy after traumatic fall Converted to arthroplasty Total arthroplasty Unicompartmental arthroplasty Patellofemoral arthroplasty
6 1 1 3 2 1 16 14 1 1
was calculated using the Kaplan-Meier method. All statistical tests were 2-tailed. A P value of .05 was used to determine statistical significance. Data were analyzed using SPSS (v13.0; SPSS Inc, IBM Corp). To determine variables related to allograft failure, we compared bipolar OCA failures and nonfailures on select variables using x2 tests for categorical variables and independent-samples t tests (or the Mann-Whitney U test when appropriate) for continuous variables.
RESULTS Further surgery on the affected knee was required in 30 (63%) of 48 knees (Table 2). Survivorship of the bipolar OCA was 64.1% at 5 years and 39% at 10 years’ follow-up (Figure 5). Twenty-two of the 48 OCA transplantations (45.8%) failed at a mean of 42 months (range, 6-118 months). The mean follow-up of the 26 knees with grafts still in situ was 84 months, ranging from 24 months (2 years) to 236 months (19.7 years). Twenty-three of the 26 nonfailures (88%) scored 15 and were considered to have good and excellent results according to the 18-point scale (Table 3). Among the nonfailures, 96% reported improved function, 92% reported reduced pain, 88% were extremely satisfied or satisfied with the procedure, and 92% stated that they would undergo OCA transplantation again under similar circumstances. The allograft size in the failure group was significantly larger when compared with that in the nonfailure group. All the other variables showed no significant differences between groups (Table 4).
DISCUSSION Survivorship of the bipolar OCA was 64.1% at 5 years’ and 39% at 10 years’ follow-up. Twenty-two of the 48 knees (46%) required major surgery (such as arthroplasty) resulting in removal of the allograft, and 8 knees (17%) required reoperations such as arthroscopy or hardware removal. However, the 26 knees (54%) that still had their allografts in situ were significantly improved (decreased pain and increased function) compared with their preoperative status. In this study, the outcomes of bipolar OCAs were
Figure 5. Survivorship of the bipolar osteochondral allograft was 64.1% at 5 years and 39% at 10 years.
TABLE 3 Results of Subjective Outcome Measuresa Instrument
Preoperative Latest Follow-up P Value
IKDC pain IKDC function Knee Society function Modified Merle d’Aubigne´-Postel (18-point)
7.5 3.4 70.5 12.1
6 6 6 6
2.2 1.5 16.5 2.0
4.7 7.0 84.1 16.1
6 6 6 6
3.1 2.0 18.6 1.4
.021 .001 .071 \.001
a Values are reported as mean 6 SD. IKDC, International Knee Documentation Committee.
inferior to the results of other studies of OCA transplantation for focal lesions of a single anatomic site. Emmerson et al9 reported on 66 knees in 64 patients who had osteochondritis dissecans. Forty-seven (72%) knees had good and excellent results at a mean 7.7 years’ follow-up. Levy et al24 reported on 129 knees undergoing OCA transplantation. In their mean 13.5 years of follow-up, survivorship of the OCA was calculated to be 82% at 10 years and 74% at 15 years. Pain and function of the patients whose allografts remained in situ were significantly improved. Although in the literature OCA transplantation has demonstrated good to excellent outcomes, bipolar OCAs have reported poorer results. Torga Spak and Teitge30 reported on 14 patellofemoral OCAs, which were implanted in 11 patients for patellofemoral arthritis. Twelve of these allografts were bipolar OCAs. At last follow-up (mean, 10 years; range, 2.5-17.5 years), 8 grafts were still in place. Chu et al6 reported on 55 patients who were treated with OCA
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TABLE 4 Comparison of Osteochondral Allograft Failures and Nonfailuresa Failures (n = 22) Age, mean 6 SD, y Male sex, % BMI, mean 6 SD, kg/m2 Previous surgery, % No. of previous surgeries, median (range) Diagnosis, % DCL/OA TCI Other Location, % Medial Lateral Patellofemoral Allograft size, median (range), cm2
Nonfailures (n = 26)
39.2 6 12.7 45.5 29.0 6 5.4 77.3 3 (1-6)
41.0 6 13.1 46.2 25.4 6 4.7 96.2 3 (1-8)
22.7 68.2 9.1
50.0 38.5 11.5
13.6 54.5 31.8 24.6 (8.5-41.0)
42.3 30.8 26.9 15.7 (4.2-31.8)
P Value .622 .961 .067 .081 .427b .108
.079
.015b
a
BMI, body mass index; DCL, degenerative chondral lesion; OA, osteoarthritis; TCI, traumatic chondral injury. Mann-Whitney U test.
b
transplantation. Forty-five (76%) knees reported good or excellent results. Bipolar OCA results were poorer, with only 6 (50%) of 12 bipolar OCA results being good or excellent in the same series at last follow-up. Bugbee and Convery5 reported a success rate of 53% at 50 months’ follow-up in 21 patients treated with bipolar OCAs. Jamali et al21 analyzed 20 knees of 18 patients who were treated with fresh OCAs. Twelve patients were treated with patellar and trochlear allografts, and 8 patients were treated with patellar allografts, of which 2 failed. In their series, good or excellent results were achieved in 60% of patients at a mean follow-up of 94 months. Bipolar tibiofemoral allografting is more challenging. Beaver at al2 reported their OCA results with 99 knees and a mean follow-up of 68 months. The allograft success rate was 75% at 5 years and 63% at 14 years. Nineteen of these were bipolar tibiofemoral allografts. The authors also replaced the meniscus with an allograft. Bipolar allografts showed a lower success rate (40%) than unipolar grafts. They suggested that unipolar OCA surgery should be performed before secondary changes on the other joint surface. Higher failure rates of bipolar allografts may be explained by biological and mechanical reasons. Biological failure can be caused by OCA immunology.11,18,22,28 The immunological response of an allograft is not fully understood. Hunt et al18 examined the relationship between osteochondral graft size and antibody response. The authors reported that antibody formation increased with an increase in allograft diameter, but they found no significant relationship between the antibody response with graft survival. Kandel et al22 examined 44 failed allografts and found no histological evidence of transplant rejection. Bipolar allograft transplantation shows the possible mechanical weakness of the medial or lateral tibiofemoral compartment at an in-between stage of transplantation and bone substitution. Ghazavi et al12 showed a clear correlation
between alignment and clinical results including bipolar defects, any varus or valgus malalignment of the knee, and joint space narrowing of .50% related to allograft failure. Shasha et al29 suggested that if preoperative full-length standing radiographs showed malalignment in the affected extremity, allografts should be protected with realignment osteotomy. Gross et al16 reported that patients undergoing concomitant osteotomy with OCAs fared better than patients with prior or delayed osteotomy. We performed concomitantly 1 HTO and 1 DFO with allograft replacement to correct the alignment of the limb and to protect the graft. The progression of cartilage disease may also be a factor in failure of this population. Bipolar kissing lesions, present in the patients in this study, reflect a higher burden of osteoarthritic disease than joints with focal or unipolar lesions.12 Jamali et al21 reported that failure of the patellofemoral allograft may be related to diffuse degenerative lesions. Horton et al,17 in a study of revision OCA transplantation in 33 knees, showed a survivorship rate of 61% at 10 years, of which 27% failed because of the progression of cartilage disease. They suggested that when an OCA is used as a salvage procedure for advanced cartilage disease, it may be associated with poorer outcomes. Large bipolar lesions may represent a later stage of cartilage disease and thus a more challenging condition to treat. Indeed, our study showed higher failure rates in patients’ allograft size with a median of 24.6 cm2 (range, 8.5-41.0 cm2), suggesting more caution with osteochondral allografting of large bipolar lesions. Our study has several limitations. We used the modified Merle d’Aubigne´-Postel (18-point) scale, but this scoring system has not been validated in the knee. This scoring system is a simple, standardized method of retrospectively evaluating patient outcomes on an objective basis and used commonly in the orthopaedic literature. In addition, our study lacks an appropriate control group such as mosaicplasty, ACI, or OAT. We lacked a radiographic follow-up.
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Radiographic long-term evaluations could provide useful information about graft union or failure and progression of the chondral injury. Also, many patients traveled long distances for treatment, and therefore, routine checkups were difficult to schedule. Telephone interviews or mailings for outcome scores provided information on basic outcome measures including graft survival, reoperation, pain, and function but may not reveal the patient’s knee status. The retrospective nature of the study also introduces potential bias. The treatment of bipolar cartilage injuries remains a difficult clinical challenge. We found higher reoperation and failure rates in this group compared with other studies when patients were treated with allografts for focal lesions of a single anatomic site. As a result, many patients treated with OCAs in this study (older age and advanced degenerative changes) would not likely be offered this treatment in our current algorithm. However, the relatively good subjective and objective clinical outcomes of patients with surviving allografts suggest a valuable role for this procedure in patients whose age and activity level would make them unsuitable for arthroplasty. We conclude that bipolar OCA transplantation can be considered as a potential biological treatment option for patients with bipolar cartilage lesions of the knee.
REFERENCES 1. Alford JW, Cole BJ. Cartilage restoration, part 1: basic science, historical perspective, patient evaluation, and treatment options. Am J Sports Med. 2005;33(2):295-306. 2. Beaver RJ, Mahomed M, Backstein D, et al. Fresh osteochondral allografts for post-traumatic defects in the knee: a survivorship analysis. J Bone Joint Surg Br. 1992;74(1):105-110. 3. Bugbee W, Cavallo M, Giannini S. Osteochondral allograft transplantation in the knee. J Knee Surg. 2012;25(2):109-116. 4. Bugbee WD. Fresh osteochondral allografts. J Knee Surg. 2002;15(3):191-195. 5. Bugbee WD, Convery FR. Osteochondral allograft transplantation. Clin Sports Med. 1999;18(1):67-75. 6. Chu CR, Convery FR, Akeson WH, et al. Articular cartilage transplantation: clinical results in the knee. Clin Orthop Relat Res. 1999;360:159-168. 7. D’Aubigne RM, Postel M. Functional results of hip arthroplasty with acrylic prosthesis. J Bone Joint Surg Am. 1954;36(3):451-475. 8. Davies-Tuck ML, Wluka AE, Wang Y, et al. The natural history of cartilage defects in people with knee osteoarthritis. Osteoarthritis Cartilage. 2008;16(3):337-342. 9. Emmerson BC, Go¨rtz S, Jamali AA, et al. Fresh osteochondral allografting in the treatment of osteochondritis dissecans of the femoral condyle. Am J Sports Med. 2007;35(6):907-914. 10. Filardo G, Kon E, Andriolo L, et al. Treatment of ‘‘patellofemoral’’ cartilage lesions with matrix-assisted autologous chondrocyte transplantation: a comparison of patellar and trochlear lesions. Am J Sports Med. 2014;42(3):626-634. 11. Garrett JC. Fresh osteochondral allografts for treatment of articular defects in osteochondritis dissecans of the lateral femoral condyle in adults. Clin Orthop Relat Res. 1994;303:33-37.
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12. Ghazavi MT, Pritzker KP, Davis AM, et al. Fresh osteochondral allografts for post-traumatic osteochondral defects of the knee. J Bone Joint Surg Br. 1997;79(6):1008-1013. 13. Gobbi A, Nunag P, Malinowski K. Treatment of full thickness chondral lesions of the knee with microfracture in a group of athletes. Knee Surg Sports Traumatol Arthrosc. 2005;13(3):213-221. 14. Go¨rtz S, Bugbee WD. Allografts in articular cartilage repair. Instr Course Lect. 2007;56:469-480. 15. Go¨rtz S, De Young AJ, Bugbee WD. Fresh osteochondral allografting for steroid-associated osteonecrosis of the femoral condyles. Clin Orthop Relat Res. 2010;468(5):1269-1278. 16. Gross AE, Shasha N, Aubin P. Long-term followup of the use of fresh osteochondral allografts for posttraumatic knee defects. Clin Orthop Relat Res. 2005;435:79-87. 17. Horton MT, Pulido PA, McCauley JC, et al. Revision osteochondral allograft transplantations: do they work? Am J Sports Med. 2013;41(11):2507-2511. 18. Hunt HE, Sadr K, Deyoung AJ, et al. The role of immunologic response in fresh osteochondral allografting of the knee. Am J Sports Med. 2014;42(4):886-891. 19. Insall J, Tria AJ, Scott WN. The total condylar knee prosthesis: the first 5 years. Clin Orthop Relat Res. 1979;145:68-77. 20. Irrgang JJ, Anderson AF, Boland AL, et al. Development and validation of the International Knee Documentation Committee subjective knee form. Am J Sports Med. 2001;29(5):600-613. 21. Jamali AA, Emmerson BC, Chung C, et al. Fresh osteochondral allografts: results in the patellofemoral joint. Clin Orthop Relat Res. 2005;437:176-185. 22. Kandel RA, Gross AE, Ganel A, et al. Histopathology of failed osteoarticular shell allografts. Clin Orthop Relat Res. 1985;197: 103-110. 23. Konst YE, Benink RJ, Veldstra R, et al. Treatment of severe osteochondral defects of the knee by combined autologous bone grafting and autologous chondrocyte implantation using fibrin gel. Knee Surg Sports Traumatol Arthrosc. 2012;20(11):2263-2269. 24. Levy YD, Go¨rtz S, Pulido PA, et al. Do fresh osteochondral allografts successfully treat femoral condyle lesions? Clin Orthop Relat Res. 2013;471(1):231-237. 25. Mandelbaum B, Browne JE, Fu F, et al. Treatment outcomes of autologous chondrocyte implantation for full-thickness articular cartilage defects of the trochlea. Am J Sports Med. 2007;35(6):915-921. 26. McAllister DR, Joyce MJ, Mann BJ, et al. Allograft update: the current status of tissue regulation, procurement, processing, and sterilization. Am J Sports Med. 2007;35(12):2148-2158. 27. Messner K, Maletius W. The long-term prognosis for severe damage to weight-bearing cartilage in the knee: a 14-year clinical and radiographic follow-up in 28 young athletes. Acta Orthop Scand. 1996;67(2):165-168. 28. Meyers MH, Akeson W, Convery FR. Resurfacing of the knee with fresh osteochondral allograft. J Bone Joint Surg Am. 1989;71(5): 704-713. 29. Shasha N, Krywulak S, Backstein D, et al. Long-term follow-up of fresh tibial osteochondral allografts for failed tibial plateau fractures. J Bone Joint Surg Am. 2003;85-A(Suppl 2):33-39. 30. Torga Spak R, Teitge RA. Fresh osteochondral allografts for patellofemoral arthritis: long-term followup. Clin Orthop Relat Res. 2006;444:193-200. 31. Vazquez-Vela Johnson G, Worland RL, Keenan J, et al. Patient demographics as a predictor of the ten-year survival rate in primary total knee replacement. J Bone Joint Surg Br. 2003;85(1):52-56. 32. Williams RJ 3rd, Ranawat AS, Potter HG, et al. Fresh stored allografts for the treatment of osteochondral defects of the knee. J Bone Joint Surg Am. 2007;89(4):718-726.
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Chondral lesions in the knee are common and potentially debilitating problems. Large or complex chondral or osteochondral lesions in particular present a difficult clinical challenge with few restorative treatment options.1 Although microfracture, osteochondral autologous transfer (OAT), and autologous chondrocyte implantation (ACI) are procedures used for cartilage lesions, their application and effectiveness decline in direct correlation to increasing lesion size and/or as a result of previously failed surgery.10,13,25 Failure is more common for bipolar, reciprocal (‘‘kissing’’) chondral lesions with or without osseous or meniscal deficiency, which constitutes a relative contraindication to these particular cartilage repair procedures.23 If not adequately treated, reciprocal lesions frequently
progress to advanced osteoarthritis, usually relegating patients to partial or total joint arthroplasty.8,27,31 Osteochondral allograft (OCA) transplantation has been recommended in recent treatment algorithms for the reconstruction of large osteochondral defects of the knee.24,32 OCA transplantation is especially utilized in active, young patients with cartilage defects in whom previous treatment procedures have failed. The fundamental principle of allografting is the replacement of injured or diseased articular cartilage and underlying bone with an orthotopic, allogenic transplant consisting of mature hyaline cartilage containing viable chondrocytes along with underlying supporting subchondral bone. The only technique that treats cartilage defects with anatomically matched hyaline cartilage, OCA transplantation has the advantage of no donor site morbidity for patients and a minor immunological response.18 A number of authors have reported on the outcome of OCAs.3-5,9,15,18 The purpose of this study was to evaluate the outcomes of patients
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TABLE 1 Demographic and Cartilage Lesion Informationa Demographics Age, mean (range), y Male/female sex, n BMI, mean (range), kg/m2 Diagnosis, n (%) TCI OA DCL Failed OCA Other (OCD, chronic subluxation, and plateau fracture) Location of the graft, n (%) Lateral tibiofemoral joint Medial tibiofemoral joint Patellofemoral joint Type of previous surgeries, n (%) Partial or total meniscectomy Ligament surgery Chondral debridement Loose body removal Subchondral marrow stimulation OAT OCA
40 (15-66) 21/25 26.8 (19.2-38.5) 25 9 9 2 3
(52.1) (18.8) (18.8) (4.2) (6.3)
20 (42) 14 (29) 14 (29) 23 7 34 7 6 1 2
(47) (14) (70) (14) (12) (2) (4)
a BMI, body mass index; DCL, degenerative chondral lesion; OA, osteoarthritis; OAT, osteochondral autologous transfer; OCA, osteochondral allograft; OCD, osteochondritis dissecans; TCI, traumatic chondral injury.
who had undergone OCA transplantation for reciprocal bipolar cartilage injuries (‘‘kissing lesions’’) of the knee.
MATERIALS AND METHODS We retrospectively identified 51 patients (53 knees) who had undergone OCA transplantation for bipolar cartilage lesions of the knee from 1983 to 2010 in an institutional review board–approved clinical database. Of the 51 patients, 5 were lost to follow-up before 2 years. Index demographic details were collected on the remaining 46 patients (48 knees) included in this study. Forty-two of the 48 (88%) knees had undergone a combined 143 previous surgeries, with a mean of 3.4 surgeries (range, 1-8). The remaining 6 knees had undergone no prior surgery. The demographic and cartilage lesion information are detailed in Table 1. The indications of this surgery were reciprocal lesions in the patellofemoral joint and tibiofemoral joint, International
Figure 1. Preoperative (A) anteroposterior and (B) lateral radiographs of a 47-year-old male show signs of right lateral compartment loss of joint space. The patient had undergone lateral meniscectomy.
Cartilage Repair Society (ICRS) grades 3 and 4, and patients who had failed previous surgical and nonsurgical interventions and/or wished to avoid prosthetic arthroplasty. Demographic, pain, and joint function data were obtained preoperatively. Donors and recipients were matched based on size using standard radiographs corrected for magnification (Figure 1). No blood or tissue typing was performed, and no immunosuppressive therapy was used.5 We obtained fresh anatomically appropriate tissue from healthy donors who met the criteria of the American Association of Tissue Banks.26 Donor tissue was recovered within 24 hours of donor death, processed, and maintained fresh at 4°C until the time of implantation, which was between 3 and 28 days from tissue recovery. The senior author (W.D.B.) performed the majority of the procedures. Surgeries were performed with the patient in a supine position under tourniquet control using full arthrotomy or miniarthrotomy through a midline incision as previously described.14 The osteoarticular lesions were identified depending on topographic characteristics (Figure 2), including affected compartment, lesion size, and location. An instrumented dowel or a freehand (shell) technique was selected. Tibial grafts consisted of hemitibial plateaus transplanted with their attached meniscus as a compound graft in cases of associated meniscal insufficiency. Patellar grafts consisted of whole surface shell grafts and then either complete corresponding trochlear groove shell grafts or focal trochlear allograft plugs. We prepared graft beds down to healthy bleeding bone using standard instruments and techniques. We tailored the grafts to orthotopically match the prepared lesion. We
{ Address correspondence to William D. Bugbee, MD, Division of Orthopaedic Surgery, Scripps Clinic, 10666 North Torrey Pines Road, MS 116, La Jolla, CA 92037, USA (e-mail: [email protected]). *Shiley Center for Orthopaedic Research and Education, Scripps Clinic, La Jolla, California, USA. y Department of Orthopaedic Surgery, Balikesir University, Balikesir, Turkey. z Department of Orthopaedic Surgery, Federal University of Sa˜o Paulo, Sa˜o Paulo, Brazil. § Department of Orthopaedic Surgery, University of California, San Diego, La Jolla, California, USA. || Division of Orthopaedic Surgery, Scripps Clinic, La Jolla, California, USA. One or more of the authors has declared the following potential conflict of interest or source of funding: W.D.B. is a consultant for and has received research support from the Joint Restoration Foundation, a nonprofit tissue bank that receives, processes, and distributes osteochondral allografts. G.M. was supported by The Scientific and Technological Research Council of Turkey (TUBITAK) (Ref: B.14.2.TBT.0.06.01-219-6040). G.C.G. was supported by Coordination for the Improvement of Higher Education Personnel (CAPES) of Brazil.
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Figure 2. Intraoperative Intraoperative image showing reciprocal bipolar articular cartilage disease with ‘‘kissing lesions’’ in the area of prior surgery and loss of the lateral meniscus in the right knee. then performed trial fittings after the grafts were copiously pulse lavaged to remove debris and marrow elements to decrease the immunogenicity of the graft. Grafts were properly positioned, and an acceptable press fit was achieved. In patients with inadequate press-fit stability, we supplemented fixation using absorbable pins (OrthoSorb; DePuy Synthes) (Figure 3). On the tibial side, we stabilized using a cannulated interfragmentary compression screw (Figures 3 and 4). On an intraoperative worksheet, we documented details regarding the procedure, including the size and location of each allograft. Thirty-four OCA procedures involved the tibiofemoral joint (20 lateral and 14 medial compartments); 14 involved the patellofemoral joint. The mean graft area for the entire group was 19.2 cm2 (range, 4.2-41.0 cm2). Twenty-two knees underwent concomitant procedures at the time of OCA transplantation. Some knees had more than 1 concomitant procedure. We performed 9 hardware removals, 7 retinacular releases (6 lateral, 1 medial), 2 meniscectomies, 2 debridements, 2 anterior cruciate ligament reconstructions, 1 lateral imbrication, 1 high tibial osteotomy (HTO), and 1 distal femoral osteotomy (DFO). Of the 34 knees that underwent tibiofemoral osteochondral allografting, 18 had a meniscal allograft (10 lateral, 8 medial). Two patients had staged bilateral allograft procedures performed at 14 months and at 96 months. Postoperatively, tibiofemoral grafts were protected with a range of motion brace, whereas patellofemoral grafts were braced in extension, limiting range of motion from full extension to 30° to avoid the patella engaging the trochlea. Postoperative care included routine physical therapy with protected weightbearing up to 3 months. Return to daily activity usually was allowed after 4 months. Closed chain exercises were started at 4 weeks and unrestricted activities of daily living at 3 to 4 months. Preoperative and postoperative clinical evaluations included the International Knee Documentation Committee
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Figure 3. Intraoperative image of a right lateral tibiofemoral bipolar compound allograft with the compound meniscus in situ after fixation with bioabsorbable chondral darts and compression screws.
Figure 4. (A) Anteroposterior weightbearing and (B) lateral radiographs show the patient 44 months after lateral bipolar tibiofemoral and meniscal allografting. (IKDC) questionnaire to measure patients’ self-reported pain and function using a visual analog scale format,20 the Knee Society function (KS-F) score,19 and the modified Merle d’Aubigne´-Postel (18-point) scale.7 Additional surgeries performed on the operative joint were documented at latest follow-up. Revision allografting, conversion to arthroplasty, arthrodesis, and patellectomy were considered failures. We assessed satisfaction with the procedure at each patient’s latest follow-up using a questionnaire, which included the following: patients’ satisfaction with the results of the surgery (5 = extremely satisfied, 1 = extremely dissatisfied), pain and function in comparison to preoperative status (better, same, worse), and whether the patient would undergo the same surgery again under similar circumstances. Patients unable to return for clinical evaluation were contacted by telephone. We analyzed preoperative and postoperative IKDC pain and function scores, KS-F scores, and 18-point scores using nonparametric Wilcoxon signed-rank tests. Survivorship
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TABLE 2 Reoperations After Allograft Surgery Procedure
n
Arthroscopic debridement Distal femoral osteotomy Hardware removal Repeat allografting Converted to arthrodesis after infection Patellectomy after traumatic fall Converted to arthroplasty Total arthroplasty Unicompartmental arthroplasty Patellofemoral arthroplasty
6 1 1 3 2 1 16 14 1 1
was calculated using the Kaplan-Meier method. All statistical tests were 2-tailed. A P value of .05 was used to determine statistical significance. Data were analyzed using SPSS (v13.0; SPSS Inc, IBM Corp). To determine variables related to allograft failure, we compared bipolar OCA failures and nonfailures on select variables using x2 tests for categorical variables and independent-samples t tests (or the Mann-Whitney U test when appropriate) for continuous variables.
RESULTS Further surgery on the affected knee was required in 30 (63%) of 48 knees (Table 2). Survivorship of the bipolar OCA was 64.1% at 5 years and 39% at 10 years’ follow-up (Figure 5). Twenty-two of the 48 OCA transplantations (45.8%) failed at a mean of 42 months (range, 6-118 months). The mean follow-up of the 26 knees with grafts still in situ was 84 months, ranging from 24 months (2 years) to 236 months (19.7 years). Twenty-three of the 26 nonfailures (88%) scored 15 and were considered to have good and excellent results according to the 18-point scale (Table 3). Among the nonfailures, 96% reported improved function, 92% reported reduced pain, 88% were extremely satisfied or satisfied with the procedure, and 92% stated that they would undergo OCA transplantation again under similar circumstances. The allograft size in the failure group was significantly larger when compared with that in the nonfailure group. All the other variables showed no significant differences between groups (Table 4).
DISCUSSION Survivorship of the bipolar OCA was 64.1% at 5 years’ and 39% at 10 years’ follow-up. Twenty-two of the 48 knees (46%) required major surgery (such as arthroplasty) resulting in removal of the allograft, and 8 knees (17%) required reoperations such as arthroscopy or hardware removal. However, the 26 knees (54%) that still had their allografts in situ were significantly improved (decreased pain and increased function) compared with their preoperative status. In this study, the outcomes of bipolar OCAs were
Figure 5. Survivorship of the bipolar osteochondral allograft was 64.1% at 5 years and 39% at 10 years.
TABLE 3 Results of Subjective Outcome Measuresa Instrument
Preoperative Latest Follow-up P Value
IKDC pain IKDC function Knee Society function Modified Merle d’Aubigne´-Postel (18-point)
7.5 3.4 70.5 12.1
6 6 6 6
2.2 1.5 16.5 2.0
4.7 7.0 84.1 16.1
6 6 6 6
3.1 2.0 18.6 1.4
.021 .001 .071 \.001
a Values are reported as mean 6 SD. IKDC, International Knee Documentation Committee.
inferior to the results of other studies of OCA transplantation for focal lesions of a single anatomic site. Emmerson et al9 reported on 66 knees in 64 patients who had osteochondritis dissecans. Forty-seven (72%) knees had good and excellent results at a mean 7.7 years’ follow-up. Levy et al24 reported on 129 knees undergoing OCA transplantation. In their mean 13.5 years of follow-up, survivorship of the OCA was calculated to be 82% at 10 years and 74% at 15 years. Pain and function of the patients whose allografts remained in situ were significantly improved. Although in the literature OCA transplantation has demonstrated good to excellent outcomes, bipolar OCAs have reported poorer results. Torga Spak and Teitge30 reported on 14 patellofemoral OCAs, which were implanted in 11 patients for patellofemoral arthritis. Twelve of these allografts were bipolar OCAs. At last follow-up (mean, 10 years; range, 2.5-17.5 years), 8 grafts were still in place. Chu et al6 reported on 55 patients who were treated with OCA
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TABLE 4 Comparison of Osteochondral Allograft Failures and Nonfailuresa Failures (n = 22) Age, mean 6 SD, y Male sex, % BMI, mean 6 SD, kg/m2 Previous surgery, % No. of previous surgeries, median (range) Diagnosis, % DCL/OA TCI Other Location, % Medial Lateral Patellofemoral Allograft size, median (range), cm2
Nonfailures (n = 26)
39.2 6 12.7 45.5 29.0 6 5.4 77.3 3 (1-6)
41.0 6 13.1 46.2 25.4 6 4.7 96.2 3 (1-8)
22.7 68.2 9.1
50.0 38.5 11.5
13.6 54.5 31.8 24.6 (8.5-41.0)
42.3 30.8 26.9 15.7 (4.2-31.8)
P Value .622 .961 .067 .081 .427b .108
.079
.015b
a
BMI, body mass index; DCL, degenerative chondral lesion; OA, osteoarthritis; TCI, traumatic chondral injury. Mann-Whitney U test.
b
transplantation. Forty-five (76%) knees reported good or excellent results. Bipolar OCA results were poorer, with only 6 (50%) of 12 bipolar OCA results being good or excellent in the same series at last follow-up. Bugbee and Convery5 reported a success rate of 53% at 50 months’ follow-up in 21 patients treated with bipolar OCAs. Jamali et al21 analyzed 20 knees of 18 patients who were treated with fresh OCAs. Twelve patients were treated with patellar and trochlear allografts, and 8 patients were treated with patellar allografts, of which 2 failed. In their series, good or excellent results were achieved in 60% of patients at a mean follow-up of 94 months. Bipolar tibiofemoral allografting is more challenging. Beaver at al2 reported their OCA results with 99 knees and a mean follow-up of 68 months. The allograft success rate was 75% at 5 years and 63% at 14 years. Nineteen of these were bipolar tibiofemoral allografts. The authors also replaced the meniscus with an allograft. Bipolar allografts showed a lower success rate (40%) than unipolar grafts. They suggested that unipolar OCA surgery should be performed before secondary changes on the other joint surface. Higher failure rates of bipolar allografts may be explained by biological and mechanical reasons. Biological failure can be caused by OCA immunology.11,18,22,28 The immunological response of an allograft is not fully understood. Hunt et al18 examined the relationship between osteochondral graft size and antibody response. The authors reported that antibody formation increased with an increase in allograft diameter, but they found no significant relationship between the antibody response with graft survival. Kandel et al22 examined 44 failed allografts and found no histological evidence of transplant rejection. Bipolar allograft transplantation shows the possible mechanical weakness of the medial or lateral tibiofemoral compartment at an in-between stage of transplantation and bone substitution. Ghazavi et al12 showed a clear correlation
between alignment and clinical results including bipolar defects, any varus or valgus malalignment of the knee, and joint space narrowing of .50% related to allograft failure. Shasha et al29 suggested that if preoperative full-length standing radiographs showed malalignment in the affected extremity, allografts should be protected with realignment osteotomy. Gross et al16 reported that patients undergoing concomitant osteotomy with OCAs fared better than patients with prior or delayed osteotomy. We performed concomitantly 1 HTO and 1 DFO with allograft replacement to correct the alignment of the limb and to protect the graft. The progression of cartilage disease may also be a factor in failure of this population. Bipolar kissing lesions, present in the patients in this study, reflect a higher burden of osteoarthritic disease than joints with focal or unipolar lesions.12 Jamali et al21 reported that failure of the patellofemoral allograft may be related to diffuse degenerative lesions. Horton et al,17 in a study of revision OCA transplantation in 33 knees, showed a survivorship rate of 61% at 10 years, of which 27% failed because of the progression of cartilage disease. They suggested that when an OCA is used as a salvage procedure for advanced cartilage disease, it may be associated with poorer outcomes. Large bipolar lesions may represent a later stage of cartilage disease and thus a more challenging condition to treat. Indeed, our study showed higher failure rates in patients’ allograft size with a median of 24.6 cm2 (range, 8.5-41.0 cm2), suggesting more caution with osteochondral allografting of large bipolar lesions. Our study has several limitations. We used the modified Merle d’Aubigne´-Postel (18-point) scale, but this scoring system has not been validated in the knee. This scoring system is a simple, standardized method of retrospectively evaluating patient outcomes on an objective basis and used commonly in the orthopaedic literature. In addition, our study lacks an appropriate control group such as mosaicplasty, ACI, or OAT. We lacked a radiographic follow-up.
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Radiographic long-term evaluations could provide useful information about graft union or failure and progression of the chondral injury. Also, many patients traveled long distances for treatment, and therefore, routine checkups were difficult to schedule. Telephone interviews or mailings for outcome scores provided information on basic outcome measures including graft survival, reoperation, pain, and function but may not reveal the patient’s knee status. The retrospective nature of the study also introduces potential bias. The treatment of bipolar cartilage injuries remains a difficult clinical challenge. We found higher reoperation and failure rates in this group compared with other studies when patients were treated with allografts for focal lesions of a single anatomic site. As a result, many patients treated with OCAs in this study (older age and advanced degenerative changes) would not likely be offered this treatment in our current algorithm. However, the relatively good subjective and objective clinical outcomes of patients with surviving allografts suggest a valuable role for this procedure in patients whose age and activity level would make them unsuitable for arthroplasty. We conclude that bipolar OCA transplantation can be considered as a potential biological treatment option for patients with bipolar cartilage lesions of the knee.
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