Original Article
Patellar Tendon Reconstruction in Total Knee Arthroplasty: A New Technique Ashok Rajgopal, MS, MCh, FRCS1
Attique Vasdev, MS1
1 Knee Unit, Medanta Bone and Joint Institute, Medanta—The Medicity,
Gurgaon, Haryana, India
Vivek Dahiya, DNB1
Address for correspondence Ashok Rajgopal, MS, MCh, FRCS, Knee Unit, Medanta Bone and Joint Institute, Medanta—The Medicity, Gurgaon, Haryana, India 122002 (e-mail: [email protected]).
Abstract
Keywords
► patellar tendon rupture ► quadriceps tendon graft ► bone block ► semitendinosus
Patellar tendon disruption is one of the most dreaded complications following total knee arthroplasty (TKA) impacting both implant function and implant longevity. To overcome the concerns regarding allografts and improve outcomes with augmentation techniques, we describe a technique, which we have successfully used over the past 4 years with good results. Seven patients underwent reconstruction for patellar tendon disruption using our technique from a cohort of eight patients. Extensor lag improved from a mean of 40 degrees to less than 5 degrees postoperatively. Range of motion improved from a mean of 105 degrees to 115 degrees of flexion. There was improvement in Knee Society Functional Score from a preoperative mean of 30 to 75 points. The Knee Society Pain Score, however, did not show much improvement. We believe our technique to be a solution to the difficult problem of patellar tendon ruptures after TKA and we continue to perform this procedure.
Extensor tendon disruptions account for 0.1 to 2.5%1 of all complications following total knee arthroplasty (TKA)2 (►Fig. 1). Patellar tendon disruptions alone account for 0.17% and is one of the most dreaded complications impacting both implant function and implant longevity. Patellar tendon ruptures are often traumatic though nontraumatic ruptures may be due to immunocompromised conditions such as rheumatoid arthritis, systemic lupus erythematosus, diabetes mellitus, and chronic steroid use. Extensive release of the patellar tendon from the tibial tuberosity to facilitate exposure during surgery may be another contributory factor.1,3,4 Surgery for stiff knees runs a high risk for patellar tendon avulsions. Patellar tendon ruptures lead to a significant extensor lag which is quite disabling for the patient. Patients also frequently present with instability while walking on uneven surfaces and negotiating stairs on account of buckling of the affected knee. Although some extension due to an intact medial and lateral retinaculum may be possible, patients are at risk of implant loosening due to hyperextension of the knee to achieve stability during the stance phase of
the gait cycle.2 This often prompts both the surgeon and patient to think of surgical intervention. Various techniques of repair have been described including sutures,5 staples,2 and wires,6 but their results have not been encouraging. Augmentation techniques using autogenous tissue such as the semitendinosus (ST) tendon,2,5 gracilis tendon,2 gastrocnemius muscle flap,7 and the free fascia lata8 have also been described. These, when combined with a direct surgical repair, have better surgical results but require prolonged immobilization leading to restricted flexion.5 Allografts8 using either the Achilles tendon or the extensor mechanism are usually considered the best means of treating patellar tendon disruptions but have given inconsistent results with reports of progressive extensor lag.8–12 Apart from being expensive, allografts may not be easily available or acceptable in certain societies and also run the risk of immune reaction and disease transmission.13 Lin and Wang14 in 2007 described the repair of patellar tendon rupture with a turndown quadriceps flap with circumferential wiring. They reported no extensor lag in their
received June 28, 2014 accepted after revision August 4, 2014
Copyright © by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA. Tel: +1(212) 584-4662.
DOI http://dx.doi.org/ 10.1055/s-0034-1390332. ISSN 1538-8506.
Downloaded by: Universite de Sherbrooke. Copyrighted material.
J Knee Surg
Patellar Tendon Reconstruction in TKA
Rajgopal et al.
Fig. 1 Preoperative clinical photograph showing sulcus in the region of patellar tendon.
patient after 2.5 years of surgery. Browne and Hanssen15 in 2011 described a novel surgical technique wherein they used a synthetic mesh (knitted microfilament polypropylene) for patellar tendon reconstruction. To overcome the concerns regarding allografts and improve outcomes with augmentation techniques, we describe a technique which we have successfully used over the past 4 years with good results. Our endeavor in this study was to evaluate the early clinical results of our surgical technique which, to our knowledge, has not been described.
Patients and Methods Between January 2009 and January 2013, seven patients underwent reconstruction for delayed patellar tendon disruption using our technique from a cohort of eight patients. One patient refused any surgery. Only patients who agreed to be operated upon, with patellar tendon ruptures following TKA (revision or primary), were included in the study. All other extensor mechanism disruptions were excluded from the study. The mean age of these seven patients at the time of
Fig. 2 Preoperative anteroposterior view showing a high riding patella. The Journal of Knee Surgery
the study was 60 years (range, 53–84). There were five female and two male patients. The average body mass index was 38 kg/m2 (range, 28.4–52.6 kg/m2). Five patients had type 2 diabetes mellitus, three patients had rheumatoid arthritis, one patient had bronchial asthma, and one was on chronic steroid use. The average time between patellar tendon injury and surgery was 3 years (range, 1.2–4 years). Four patients had patellar tendon ruptures following a fall, two had chronic ruptures, and one had a rupture following revision TKA in the immediate postoperative period. Four patients had previous revision surgeries. All patients underwent the same procedure for patellar tendon ruptures. One of the patients had loosening of the primary implant as evident on the X-ray and simultaneous revision TKA and patellar tendon reconstruction was done. There were two patellar tendon ruptures on the right and five on the left. None of the patients gave any history of any previous surgery to address the patellar tendon disruption. Clinical examination included measurement of extensor lag by two independent surgeons to prevent bias. This was done both pre- and postoperatively. Radiographs included anteroposterior standing (►Fig. 2), lateral views (►Fig. 3), and the merchant patellar skyline views (►Fig. 4) of both knees. The same radiographer was requested to do the X-rays in all patients to prevent any error. Though there are various methods to measure patella alta such as the Insall Salvati index, the modified Insall Salvati index, the Blackburne-Peel
Fig. 4 Preoperative skyline view.
Downloaded by: Universite de Sherbrooke. Copyrighted material.
Fig. 3 Preoperative lateral view.
Patellar Tendon Reconstruction in TKA
Rajgopal et al.
Fig. 5 Insall Salvati index.
Surgical Technique The patient was positioned supine on the operating table and a tourniquet was applied. After inflating the tourniquet, the extensor mechanism was exposed using the existing longitudinal skin incision extending proximally. The quadriceps
Fig. 6 Postoperative X-ray following repair.
tendon was exposed 8 cm proximal superior pole of the patella. Using a cautery, a rectangular block of bone measuring 15 mm in width and 25 mm in length was marked on the patella. This bone block was harvested with a saw (depth, 15 mm) along with quadriceps tendon for a length of 100 mm and width of 15 mm (►Figs. 7 and 8). The defect in the quadriceps tendon was then sutured using absorbable no. 1 Vicryl (Ethicon, Johnson & Johnson Ltd., India). The tibial tuberosity was then identified using intraoperative radiography and a trough measuring 25 mm in length, 15 mm in width, and 15 mm in depth was created with a saw on the anterior tibial cortex (►Fig. 9). This resected bone block was used to fill up the defect in the patella. The bone component of the patellar graft was trimmed to snugly fit the tibial trough site. The bone plug was fixed with the help of two 3.5 mm partially threaded cancellous screws (►Fig. 10). The ST was harvested at this stage with an open tendon stripper keeping the distal attachment intact and passed through a drill hole just distal to the tibial tubercle. A 4.5-mm drill hole was made at the center of the patella and the ST passed through it from the lateral to the medial side. The tendon end of the quadriceps graft was split longitudinally in the midline for a distance of 25 mm. The two split ends of the tendon end of the graft
Fig. 8 Quadriceps tendon patellar bone graft.
The Journal of Knee Surgery
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index, and the Caton-Deschamps method, we used the Insall Salvati index, as it is widely used, easily interpreted, and gives a predictable value of patellar position (►Fig. 5). The Insall Salvati index is the ratio of the length of the patellar tendon along its posterior surface from its origin along the inferior pole of the patella to its insertion in the tibial tubercle to the greatest pole-to-pole length of the patella measured ideally on 30-degree lateral views. A ratio of more than 1.2 indicates patella alta and less than 0.8 indicates patella baja. The alta of the patella in such situations, on lateral views, gives rise to suspicion of injury to the patella tendon when compared with previous postoperative X-rays or X-rays of the opposite operated side. The Knee Society Score and range of motion were calculated both pre- and postoperatively. Follow-up was done at 3 and 6 weeks, and at 3-month intervals thereafter. Follow-up assessment included measurement of extensor lag, recording of the Knee Society Scores at 3-month intervals, and X-rays at final follow-up (►Fig. 6). Prior consent for surgery was taken from all patients and approval obtained from the institutional review board.
Fig. 7 Trough in patella after quadriceps tendon patellar bone graft harvest.
Patellar Tendon Reconstruction in TKA
Rajgopal et al.
were then fixed to the anterior surface patella with bioabsorbable anchors and then sutured to the soft tissues around the edges of the bony graft harvest site at the patella proximally. The ST was then pulled distally by the assistant, and this along with the quadriceps tendon sutured to the medial and lateral retinaculum with the remnant of the native patellar tendon with the knee in full extension and the patella in the patellar groove. The ST was then sutured onto itself at its attachment (►Fig. 11). Integrity of the repair was tested by carefully flexing the knee to 30 degrees. The knee was closed in 30 degrees of flexion. Intra-articular drains were used and the wound was closed in layers. Intraoperative radiographs were taken just before the final closure to ensure that the patellar height was restored. Postoperatively the knee was immobilized in a long leg brace for a period of 8 to 10 weeks and partial weight bearing was allowed as per tolerance of pain. Isometric quadriceps exercises were encouraged but straight leg raising not permitted for 6 weeks postoperatively. Full weight bearing was started once the brace was removed at 8 to 10 weeks and knee range of motion gradually increased by 10 to 15 degrees every week with a goal to reach 90 degrees of flexion by the end of 12 weeks. Active knee flexion was not permitted for 8 weeks
Fig. 11 After final reconstruction.
postoperatively, but assisted knee flexion was started at 6 weeks. All, except one, patients did not require any walking aid 3 months after surgery.
Results Our surgical repair technique provided a successful result in six patients. One patient had an extensor lag of 15 degrees till recent follow-up 18 months after the surgery. There was improvement of preoperative extensor lag from a mean of 40 degrees (range, 20–60 degrees) to less than 5 degrees postoperatively (range, < 5–15 degrees) (p ¼ 0.018) at the most recent follow-up. No progressive lag was evident over time. Range of motion improved from a mean of 105 degrees of flexion (range, 100–120 degrees) preoperatively to 115 degrees of flexion (range, 100–130 degrees) (p ¼ 0.028) postoperatively (►Table 1). The mean Insall Salvati index improved from a preoperative mean of 1.8 (range, 1.6–1.95) to 1.18 (range, 1.0–1.4) postoperatively. There was improvement in the Knee Society Functional Score from a preoperative mean of 30 points to a postoperative mean of 75 points (p ¼ 0.018). The Knee Society Pain Score, however, did not show much improvement (preoperative 65 points to postoperative 70 points).
Discussion
Fig. 10 Quadriceps tendon patellar bone graft after fixing with screws in the tibial tuberosity trough. The Journal of Knee Surgery
Patellar tendon rupture is one of the most dreaded complications following TKA, with repairs giving unsatisfactory results as it leaves the patient with a persistent extensor lag. Options varied from accepting the existing dysfunctional condition to resorting to an arthrodesis.
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Fig. 9 Trough in tibial tuberosity with semitendinosus intact at attachment site.
Patellar Tendon Reconstruction in TKA
Rajgopal et al.
Table 1 Descriptive statistics Extension lag pre-op
Extension lag post-op
Flexion pre-op
Flexion post-op
Knee Society Pain Score pre-op
Knee Society Pain Score post-op
Knee Society Functional Score pre-op
Knee Society Functional Score post-op
Mean
40.0
4.8
105.0
115.0
65.0
70.0
30.1
69.7
SD
14.2
4.8
12.8
9.4
3.9
4.1
8.0
7.6
Minimum
20.0
0.0
80.0
100.0
60.0
65.0
20.0
55.0
Maximum
60.0
15.0
120.0
130.0
70.0
75.0
40.0
78.0
In a series of 18 patellar tendon ruptures treated by direct repair, Rand et al2 reported only four successful results. Oglesby and Wilson16 reported full extension in only one patient in their series of five patients with direct repair. Lynch et al1 reported poor results in all their patients of direct repair. Emerson et al17 reported satisfactory results with various allografts, whereas Leopold et al9 using similar techniques had unsatisfactory results. Restriction of flexion was an issue following repair by double ST tendon as reported by Cadambi and Engh.4 Lin and Wang14 in a recent (2011) case report advocated the use of a turndown rectangular quadriceps tendon flap based on a triangular turndown flap of the quadriceps tendon to reinforce and repair the ruptured quadriceps tendon as described by Scuderi.18 Gastrocnemius flaps gave good soft tissue coverage and return of extension at the knee but had poor cosmesis and led to weakness of planter flexion.19,20 With the availability of allografts8 and synthetic scaffolds like woven monofilament mesh,15 the possibility of much improved function has added hope for the patient. Meshes provide a framework for host tissue ingrowth with collagen formation which resembles normal ligament tissue,21,22 providing tensile strength and resistance to elongation over time though some foreign body reaction has been seen. Allografts, after showing initial encouraging clinical results, showed deterioration over time17 with the development of progressive extensor lag due to attenuation and stretching.9,11 These in addition carry the risk of disease transmission.13 To the best of our knowledge, the technique described by us has not been described earlier. This technique does away with the problems of allografts such as disease transmission13 and uses the patient’s own tissues to augment a damaged structure. Although there is a possibility of nonunion at the tuberosity site,9,23 as in the case of allografts, no nonunions were noticed in our study. We also did not record any progressive extensor lag over time. The monofilament mesh can theoretically be a nidus for infection being a foreign body. However, the infection in one case reported by Browne and Hanssen15 was not attributed to the mesh. It must be noted that five of the seven patients in our study had diabetes mellitus, which is known to be a risk issue for quadriceps and patellar tendon rupture15,24,25 and may have contributed to the initial rupture of the patellar tendon. Although diabetes mellitus was identified as a risk factor for inferior outcomes following patellar tendon reconstruction, it did not seem to
have a bearing on our results.15 Additional augmentation with the ST to the quadriceps tendon and suturing the remnant of the native tendon to both the augments allowed us to rehabilitate the patient early (8 weeks) and this may have contributed to the good results of our patients. Our experience includes one case of primary resurfaced patella. We performed the same procedure using a smaller patellar notch. We believe this to be a viable alternative in these cases. We also submit that the results of this procedure would probably outweigh the risks. Lack of comparative group especially with those treated with allografts and a number of cases given the uncommon nature of this complication can be seen as a limitation of our study. In this study, we were able to achieve good flexion postoperatively. Our preference for fixing the graft at 30 degrees of flexion was due to concern and reports in the literature of postoperative restriction of flexion when grafts were fixed at full extension.4 Our surgical technique seems to have the benefit of using the patient’s native tissue eliminating the potential complications of other techniques. Favorable extension gain with no further extensor lag over time makes us believe our technique to be a solution to the difficult problem of patellar tendon ruptures after TKA and we continue to perform this procedure.
References 1 Lynch AF, Rorabeck CH, Bourne RB. Extensor mechanism compli-
2 3 4
5 6
7
cations following total knee arthroplasty. J Arthroplasty 1987; 2(2):135–140 Rand JA, Morrey BF, Bryan RS. Patellar tendon rupture after total knee arthroplasty. Clin Orthop Relat Res 1989;(244):233–238 Rand JA. Extensor mechanism complications following total knee arthroplasty. J Knee Surg 2003;16(4):224–228 Cadambi A, Engh GA. Use of a semitendinosus tendon autogenous graft for rupture of the patellar ligament after total knee arthroplasty. A report of seven cases. J Bone Joint Surg Am 1992;74(7):974–979 Grace JN, Rand JA. Patellar instability after total knee arthroplasty. Clin Orthop Relat Res 1988;(237):184–189 Abril JC, Alvarez L, Vallejo JC. Patellar tendon avulsion after total knee arthroplasty. A new technique. J Arthroplasty 1995;10(3): 275–279 Jaureguito JW, Dubois CM, Smith SR, Gottlieb LJ, Finn HA. Medial gastrocnemius transposition flap for the treatment of disruption of the extensor mechanism after total knee arthroplasty. J Bone Joint Surg Am 1997;79(6):866–873 The Journal of Knee Surgery
Downloaded by: Universite de Sherbrooke. Copyrighted material.
Abbreviation: SD, standard deviation.
Rajgopal et al.
8 Springer BD, Della Valle CJ. Extensor mechanism allograft recon-
17 Emerson RH Jr, Head WC, Malinin TI. Extensor mechanism recon-
struction after total knee arthroplasty. J Arthroplasty 2008;23(7, Suppl)35–38 Leopold SS, Greidanus N, Paprosky WG, Berger RA, Rosenberg AG. High rate of failure of allograft reconstruction of the extensor mechanism after total knee arthroplasty. J Bone Joint Surg Am 1999;81(11):1574–1579 Parker DA, Dunbar MJ, Rorabeck CH. Extensor mechanism failure associated with total knee arthroplasty: prevention and management. J Am Acad Orthop Surg 2003;11(4):238–247 Burnett RS, Berger RA, Paprosky WG, Della Valle CJ, Jacobs JJ, Rosenberg AG. Extensor mechanism allograft reconstruction after total knee arthroplasty. A comparison of two techniques. J Bone Joint Surg Am 2004;86-A(12):2694–2699 Nazarian DG, Booth RE Jr. Extensor mechanism allografts in total knee arthroplasty. Clin Orthop Relat Res 1999;(367):123–129 Eastlund T. Bacterial infection transmitted by human tissue allograft transplantation. Cell Tissue Bank 2006;7(3):147–166 Lin PC, Wang JW. Use of a turndown quadriceps tendon flap for rupture of the patellar tendon after total knee arthroplasty. J Arthroplasty 2007;22(6):934–938 Browne JA, Hanssen AD. Reconstruction of patellar tendon disruption after total knee arthroplasty: results of a new technique utilizing synthetic mesh. J Bone Joint Surg Am 2011;93(12): 1137–1143 Oglesby JW, Wilson FC. The evolution of knee arthroplasty. Results with three generations of prostheses. Clin Orthop Relat Res 1984; (186):96–103
struction with an allograft after total knee arthroplasty. Clin Orthop Relat Res 1994;(303):79–85 Scuderi C. Ruptures of the quadriceps tendon; study of twenty tendon ruptures. Am J Surg 1958;95(4):626–634 Pagnano MW. Patellar tendon and quadriceps tendon tears after total knee arthroplasty. J Knee Surg 2003;16(4):242–247 Rand JA. Extensor mechanism complications following total knee arthroplasty. J Bone Joint Surg Am 2004;86(9):2062–2072 Hosey G, Kowalchick E, Tesoro D, et al. Comparison of the mechanical and histologic properties of Achilles tendons in New Zealand white rabbits secondarily repaired with Marlex mesh. J Foot Surg 1991;30(3):214–233 Winston LA, Terry AF, Jardine JH, Parrish FF. The result of replacement of partial or total collateral ligaments with Marlex mesh in the knees of dogs. Clin Orthop Relat Res 1978;(137): 287–290 Crossett LS, Sinha RK, Sechriest VF, Rubash HE. Reconstruction of a ruptured patellar tendon with Achilles tendon allograft following total knee arthroplasty. J Bone Joint Surg Am 2002;84-A(8): 1354–1361 Altinel L, Kose KC, Degirmenci B, Petik B, Acarturk G, Colbay M. The midterm effects of diabetes mellitus on quadriceps and patellar tendons in patients with knee arthrosis: a comparative radiological study. J Diabetes Complications 2007;21(6): 392–396 Ilan DI, Tejwani N, Keschner M, Leibman M. Quadriceps tendon rupture. J Am Acad Orthop Surg 2003;11(3):192–200
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12 13 14
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16
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Patellar Tendon Reconstruction in TKA
Patellar Tendon Reconstruction in Total Knee Arthroplasty: A New Technique Ashok Rajgopal, MS, MCh, FRCS1
Attique Vasdev, MS1
1 Knee Unit, Medanta Bone and Joint Institute, Medanta—The Medicity,
Gurgaon, Haryana, India
Vivek Dahiya, DNB1
Address for correspondence Ashok Rajgopal, MS, MCh, FRCS, Knee Unit, Medanta Bone and Joint Institute, Medanta—The Medicity, Gurgaon, Haryana, India 122002 (e-mail: [email protected]).
Abstract
Keywords
► patellar tendon rupture ► quadriceps tendon graft ► bone block ► semitendinosus
Patellar tendon disruption is one of the most dreaded complications following total knee arthroplasty (TKA) impacting both implant function and implant longevity. To overcome the concerns regarding allografts and improve outcomes with augmentation techniques, we describe a technique, which we have successfully used over the past 4 years with good results. Seven patients underwent reconstruction for patellar tendon disruption using our technique from a cohort of eight patients. Extensor lag improved from a mean of 40 degrees to less than 5 degrees postoperatively. Range of motion improved from a mean of 105 degrees to 115 degrees of flexion. There was improvement in Knee Society Functional Score from a preoperative mean of 30 to 75 points. The Knee Society Pain Score, however, did not show much improvement. We believe our technique to be a solution to the difficult problem of patellar tendon ruptures after TKA and we continue to perform this procedure.
Extensor tendon disruptions account for 0.1 to 2.5%1 of all complications following total knee arthroplasty (TKA)2 (►Fig. 1). Patellar tendon disruptions alone account for 0.17% and is one of the most dreaded complications impacting both implant function and implant longevity. Patellar tendon ruptures are often traumatic though nontraumatic ruptures may be due to immunocompromised conditions such as rheumatoid arthritis, systemic lupus erythematosus, diabetes mellitus, and chronic steroid use. Extensive release of the patellar tendon from the tibial tuberosity to facilitate exposure during surgery may be another contributory factor.1,3,4 Surgery for stiff knees runs a high risk for patellar tendon avulsions. Patellar tendon ruptures lead to a significant extensor lag which is quite disabling for the patient. Patients also frequently present with instability while walking on uneven surfaces and negotiating stairs on account of buckling of the affected knee. Although some extension due to an intact medial and lateral retinaculum may be possible, patients are at risk of implant loosening due to hyperextension of the knee to achieve stability during the stance phase of
the gait cycle.2 This often prompts both the surgeon and patient to think of surgical intervention. Various techniques of repair have been described including sutures,5 staples,2 and wires,6 but their results have not been encouraging. Augmentation techniques using autogenous tissue such as the semitendinosus (ST) tendon,2,5 gracilis tendon,2 gastrocnemius muscle flap,7 and the free fascia lata8 have also been described. These, when combined with a direct surgical repair, have better surgical results but require prolonged immobilization leading to restricted flexion.5 Allografts8 using either the Achilles tendon or the extensor mechanism are usually considered the best means of treating patellar tendon disruptions but have given inconsistent results with reports of progressive extensor lag.8–12 Apart from being expensive, allografts may not be easily available or acceptable in certain societies and also run the risk of immune reaction and disease transmission.13 Lin and Wang14 in 2007 described the repair of patellar tendon rupture with a turndown quadriceps flap with circumferential wiring. They reported no extensor lag in their
received June 28, 2014 accepted after revision August 4, 2014
Copyright © by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA. Tel: +1(212) 584-4662.
DOI http://dx.doi.org/ 10.1055/s-0034-1390332. ISSN 1538-8506.
Downloaded by: Universite de Sherbrooke. Copyrighted material.
J Knee Surg
Patellar Tendon Reconstruction in TKA
Rajgopal et al.
Fig. 1 Preoperative clinical photograph showing sulcus in the region of patellar tendon.
patient after 2.5 years of surgery. Browne and Hanssen15 in 2011 described a novel surgical technique wherein they used a synthetic mesh (knitted microfilament polypropylene) for patellar tendon reconstruction. To overcome the concerns regarding allografts and improve outcomes with augmentation techniques, we describe a technique which we have successfully used over the past 4 years with good results. Our endeavor in this study was to evaluate the early clinical results of our surgical technique which, to our knowledge, has not been described.
Patients and Methods Between January 2009 and January 2013, seven patients underwent reconstruction for delayed patellar tendon disruption using our technique from a cohort of eight patients. One patient refused any surgery. Only patients who agreed to be operated upon, with patellar tendon ruptures following TKA (revision or primary), were included in the study. All other extensor mechanism disruptions were excluded from the study. The mean age of these seven patients at the time of
Fig. 2 Preoperative anteroposterior view showing a high riding patella. The Journal of Knee Surgery
the study was 60 years (range, 53–84). There were five female and two male patients. The average body mass index was 38 kg/m2 (range, 28.4–52.6 kg/m2). Five patients had type 2 diabetes mellitus, three patients had rheumatoid arthritis, one patient had bronchial asthma, and one was on chronic steroid use. The average time between patellar tendon injury and surgery was 3 years (range, 1.2–4 years). Four patients had patellar tendon ruptures following a fall, two had chronic ruptures, and one had a rupture following revision TKA in the immediate postoperative period. Four patients had previous revision surgeries. All patients underwent the same procedure for patellar tendon ruptures. One of the patients had loosening of the primary implant as evident on the X-ray and simultaneous revision TKA and patellar tendon reconstruction was done. There were two patellar tendon ruptures on the right and five on the left. None of the patients gave any history of any previous surgery to address the patellar tendon disruption. Clinical examination included measurement of extensor lag by two independent surgeons to prevent bias. This was done both pre- and postoperatively. Radiographs included anteroposterior standing (►Fig. 2), lateral views (►Fig. 3), and the merchant patellar skyline views (►Fig. 4) of both knees. The same radiographer was requested to do the X-rays in all patients to prevent any error. Though there are various methods to measure patella alta such as the Insall Salvati index, the modified Insall Salvati index, the Blackburne-Peel
Fig. 4 Preoperative skyline view.
Downloaded by: Universite de Sherbrooke. Copyrighted material.
Fig. 3 Preoperative lateral view.
Patellar Tendon Reconstruction in TKA
Rajgopal et al.
Fig. 5 Insall Salvati index.
Surgical Technique The patient was positioned supine on the operating table and a tourniquet was applied. After inflating the tourniquet, the extensor mechanism was exposed using the existing longitudinal skin incision extending proximally. The quadriceps
Fig. 6 Postoperative X-ray following repair.
tendon was exposed 8 cm proximal superior pole of the patella. Using a cautery, a rectangular block of bone measuring 15 mm in width and 25 mm in length was marked on the patella. This bone block was harvested with a saw (depth, 15 mm) along with quadriceps tendon for a length of 100 mm and width of 15 mm (►Figs. 7 and 8). The defect in the quadriceps tendon was then sutured using absorbable no. 1 Vicryl (Ethicon, Johnson & Johnson Ltd., India). The tibial tuberosity was then identified using intraoperative radiography and a trough measuring 25 mm in length, 15 mm in width, and 15 mm in depth was created with a saw on the anterior tibial cortex (►Fig. 9). This resected bone block was used to fill up the defect in the patella. The bone component of the patellar graft was trimmed to snugly fit the tibial trough site. The bone plug was fixed with the help of two 3.5 mm partially threaded cancellous screws (►Fig. 10). The ST was harvested at this stage with an open tendon stripper keeping the distal attachment intact and passed through a drill hole just distal to the tibial tubercle. A 4.5-mm drill hole was made at the center of the patella and the ST passed through it from the lateral to the medial side. The tendon end of the quadriceps graft was split longitudinally in the midline for a distance of 25 mm. The two split ends of the tendon end of the graft
Fig. 8 Quadriceps tendon patellar bone graft.
The Journal of Knee Surgery
Downloaded by: Universite de Sherbrooke. Copyrighted material.
index, and the Caton-Deschamps method, we used the Insall Salvati index, as it is widely used, easily interpreted, and gives a predictable value of patellar position (►Fig. 5). The Insall Salvati index is the ratio of the length of the patellar tendon along its posterior surface from its origin along the inferior pole of the patella to its insertion in the tibial tubercle to the greatest pole-to-pole length of the patella measured ideally on 30-degree lateral views. A ratio of more than 1.2 indicates patella alta and less than 0.8 indicates patella baja. The alta of the patella in such situations, on lateral views, gives rise to suspicion of injury to the patella tendon when compared with previous postoperative X-rays or X-rays of the opposite operated side. The Knee Society Score and range of motion were calculated both pre- and postoperatively. Follow-up was done at 3 and 6 weeks, and at 3-month intervals thereafter. Follow-up assessment included measurement of extensor lag, recording of the Knee Society Scores at 3-month intervals, and X-rays at final follow-up (►Fig. 6). Prior consent for surgery was taken from all patients and approval obtained from the institutional review board.
Fig. 7 Trough in patella after quadriceps tendon patellar bone graft harvest.
Patellar Tendon Reconstruction in TKA
Rajgopal et al.
were then fixed to the anterior surface patella with bioabsorbable anchors and then sutured to the soft tissues around the edges of the bony graft harvest site at the patella proximally. The ST was then pulled distally by the assistant, and this along with the quadriceps tendon sutured to the medial and lateral retinaculum with the remnant of the native patellar tendon with the knee in full extension and the patella in the patellar groove. The ST was then sutured onto itself at its attachment (►Fig. 11). Integrity of the repair was tested by carefully flexing the knee to 30 degrees. The knee was closed in 30 degrees of flexion. Intra-articular drains were used and the wound was closed in layers. Intraoperative radiographs were taken just before the final closure to ensure that the patellar height was restored. Postoperatively the knee was immobilized in a long leg brace for a period of 8 to 10 weeks and partial weight bearing was allowed as per tolerance of pain. Isometric quadriceps exercises were encouraged but straight leg raising not permitted for 6 weeks postoperatively. Full weight bearing was started once the brace was removed at 8 to 10 weeks and knee range of motion gradually increased by 10 to 15 degrees every week with a goal to reach 90 degrees of flexion by the end of 12 weeks. Active knee flexion was not permitted for 8 weeks
Fig. 11 After final reconstruction.
postoperatively, but assisted knee flexion was started at 6 weeks. All, except one, patients did not require any walking aid 3 months after surgery.
Results Our surgical repair technique provided a successful result in six patients. One patient had an extensor lag of 15 degrees till recent follow-up 18 months after the surgery. There was improvement of preoperative extensor lag from a mean of 40 degrees (range, 20–60 degrees) to less than 5 degrees postoperatively (range, < 5–15 degrees) (p ¼ 0.018) at the most recent follow-up. No progressive lag was evident over time. Range of motion improved from a mean of 105 degrees of flexion (range, 100–120 degrees) preoperatively to 115 degrees of flexion (range, 100–130 degrees) (p ¼ 0.028) postoperatively (►Table 1). The mean Insall Salvati index improved from a preoperative mean of 1.8 (range, 1.6–1.95) to 1.18 (range, 1.0–1.4) postoperatively. There was improvement in the Knee Society Functional Score from a preoperative mean of 30 points to a postoperative mean of 75 points (p ¼ 0.018). The Knee Society Pain Score, however, did not show much improvement (preoperative 65 points to postoperative 70 points).
Discussion
Fig. 10 Quadriceps tendon patellar bone graft after fixing with screws in the tibial tuberosity trough. The Journal of Knee Surgery
Patellar tendon rupture is one of the most dreaded complications following TKA, with repairs giving unsatisfactory results as it leaves the patient with a persistent extensor lag. Options varied from accepting the existing dysfunctional condition to resorting to an arthrodesis.
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Fig. 9 Trough in tibial tuberosity with semitendinosus intact at attachment site.
Patellar Tendon Reconstruction in TKA
Rajgopal et al.
Table 1 Descriptive statistics Extension lag pre-op
Extension lag post-op
Flexion pre-op
Flexion post-op
Knee Society Pain Score pre-op
Knee Society Pain Score post-op
Knee Society Functional Score pre-op
Knee Society Functional Score post-op
Mean
40.0
4.8
105.0
115.0
65.0
70.0
30.1
69.7
SD
14.2
4.8
12.8
9.4
3.9
4.1
8.0
7.6
Minimum
20.0
0.0
80.0
100.0
60.0
65.0
20.0
55.0
Maximum
60.0
15.0
120.0
130.0
70.0
75.0
40.0
78.0
In a series of 18 patellar tendon ruptures treated by direct repair, Rand et al2 reported only four successful results. Oglesby and Wilson16 reported full extension in only one patient in their series of five patients with direct repair. Lynch et al1 reported poor results in all their patients of direct repair. Emerson et al17 reported satisfactory results with various allografts, whereas Leopold et al9 using similar techniques had unsatisfactory results. Restriction of flexion was an issue following repair by double ST tendon as reported by Cadambi and Engh.4 Lin and Wang14 in a recent (2011) case report advocated the use of a turndown rectangular quadriceps tendon flap based on a triangular turndown flap of the quadriceps tendon to reinforce and repair the ruptured quadriceps tendon as described by Scuderi.18 Gastrocnemius flaps gave good soft tissue coverage and return of extension at the knee but had poor cosmesis and led to weakness of planter flexion.19,20 With the availability of allografts8 and synthetic scaffolds like woven monofilament mesh,15 the possibility of much improved function has added hope for the patient. Meshes provide a framework for host tissue ingrowth with collagen formation which resembles normal ligament tissue,21,22 providing tensile strength and resistance to elongation over time though some foreign body reaction has been seen. Allografts, after showing initial encouraging clinical results, showed deterioration over time17 with the development of progressive extensor lag due to attenuation and stretching.9,11 These in addition carry the risk of disease transmission.13 To the best of our knowledge, the technique described by us has not been described earlier. This technique does away with the problems of allografts such as disease transmission13 and uses the patient’s own tissues to augment a damaged structure. Although there is a possibility of nonunion at the tuberosity site,9,23 as in the case of allografts, no nonunions were noticed in our study. We also did not record any progressive extensor lag over time. The monofilament mesh can theoretically be a nidus for infection being a foreign body. However, the infection in one case reported by Browne and Hanssen15 was not attributed to the mesh. It must be noted that five of the seven patients in our study had diabetes mellitus, which is known to be a risk issue for quadriceps and patellar tendon rupture15,24,25 and may have contributed to the initial rupture of the patellar tendon. Although diabetes mellitus was identified as a risk factor for inferior outcomes following patellar tendon reconstruction, it did not seem to
have a bearing on our results.15 Additional augmentation with the ST to the quadriceps tendon and suturing the remnant of the native tendon to both the augments allowed us to rehabilitate the patient early (8 weeks) and this may have contributed to the good results of our patients. Our experience includes one case of primary resurfaced patella. We performed the same procedure using a smaller patellar notch. We believe this to be a viable alternative in these cases. We also submit that the results of this procedure would probably outweigh the risks. Lack of comparative group especially with those treated with allografts and a number of cases given the uncommon nature of this complication can be seen as a limitation of our study. In this study, we were able to achieve good flexion postoperatively. Our preference for fixing the graft at 30 degrees of flexion was due to concern and reports in the literature of postoperative restriction of flexion when grafts were fixed at full extension.4 Our surgical technique seems to have the benefit of using the patient’s native tissue eliminating the potential complications of other techniques. Favorable extension gain with no further extensor lag over time makes us believe our technique to be a solution to the difficult problem of patellar tendon ruptures after TKA and we continue to perform this procedure.
References 1 Lynch AF, Rorabeck CH, Bourne RB. Extensor mechanism compli-
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cations following total knee arthroplasty. J Arthroplasty 1987; 2(2):135–140 Rand JA, Morrey BF, Bryan RS. Patellar tendon rupture after total knee arthroplasty. Clin Orthop Relat Res 1989;(244):233–238 Rand JA. Extensor mechanism complications following total knee arthroplasty. J Knee Surg 2003;16(4):224–228 Cadambi A, Engh GA. Use of a semitendinosus tendon autogenous graft for rupture of the patellar ligament after total knee arthroplasty. A report of seven cases. J Bone Joint Surg Am 1992;74(7):974–979 Grace JN, Rand JA. Patellar instability after total knee arthroplasty. Clin Orthop Relat Res 1988;(237):184–189 Abril JC, Alvarez L, Vallejo JC. Patellar tendon avulsion after total knee arthroplasty. A new technique. J Arthroplasty 1995;10(3): 275–279 Jaureguito JW, Dubois CM, Smith SR, Gottlieb LJ, Finn HA. Medial gastrocnemius transposition flap for the treatment of disruption of the extensor mechanism after total knee arthroplasty. J Bone Joint Surg Am 1997;79(6):866–873 The Journal of Knee Surgery
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Abbreviation: SD, standard deviation.
Rajgopal et al.
8 Springer BD, Della Valle CJ. Extensor mechanism allograft recon-
17 Emerson RH Jr, Head WC, Malinin TI. Extensor mechanism recon-
struction after total knee arthroplasty. J Arthroplasty 2008;23(7, Suppl)35–38 Leopold SS, Greidanus N, Paprosky WG, Berger RA, Rosenberg AG. High rate of failure of allograft reconstruction of the extensor mechanism after total knee arthroplasty. J Bone Joint Surg Am 1999;81(11):1574–1579 Parker DA, Dunbar MJ, Rorabeck CH. Extensor mechanism failure associated with total knee arthroplasty: prevention and management. J Am Acad Orthop Surg 2003;11(4):238–247 Burnett RS, Berger RA, Paprosky WG, Della Valle CJ, Jacobs JJ, Rosenberg AG. Extensor mechanism allograft reconstruction after total knee arthroplasty. A comparison of two techniques. J Bone Joint Surg Am 2004;86-A(12):2694–2699 Nazarian DG, Booth RE Jr. Extensor mechanism allografts in total knee arthroplasty. Clin Orthop Relat Res 1999;(367):123–129 Eastlund T. Bacterial infection transmitted by human tissue allograft transplantation. Cell Tissue Bank 2006;7(3):147–166 Lin PC, Wang JW. Use of a turndown quadriceps tendon flap for rupture of the patellar tendon after total knee arthroplasty. J Arthroplasty 2007;22(6):934–938 Browne JA, Hanssen AD. Reconstruction of patellar tendon disruption after total knee arthroplasty: results of a new technique utilizing synthetic mesh. J Bone Joint Surg Am 2011;93(12): 1137–1143 Oglesby JW, Wilson FC. The evolution of knee arthroplasty. Results with three generations of prostheses. Clin Orthop Relat Res 1984; (186):96–103
struction with an allograft after total knee arthroplasty. Clin Orthop Relat Res 1994;(303):79–85 Scuderi C. Ruptures of the quadriceps tendon; study of twenty tendon ruptures. Am J Surg 1958;95(4):626–634 Pagnano MW. Patellar tendon and quadriceps tendon tears after total knee arthroplasty. J Knee Surg 2003;16(4):242–247 Rand JA. Extensor mechanism complications following total knee arthroplasty. J Bone Joint Surg Am 2004;86(9):2062–2072 Hosey G, Kowalchick E, Tesoro D, et al. Comparison of the mechanical and histologic properties of Achilles tendons in New Zealand white rabbits secondarily repaired with Marlex mesh. J Foot Surg 1991;30(3):214–233 Winston LA, Terry AF, Jardine JH, Parrish FF. The result of replacement of partial or total collateral ligaments with Marlex mesh in the knees of dogs. Clin Orthop Relat Res 1978;(137): 287–290 Crossett LS, Sinha RK, Sechriest VF, Rubash HE. Reconstruction of a ruptured patellar tendon with Achilles tendon allograft following total knee arthroplasty. J Bone Joint Surg Am 2002;84-A(8): 1354–1361 Altinel L, Kose KC, Degirmenci B, Petik B, Acarturk G, Colbay M. The midterm effects of diabetes mellitus on quadriceps and patellar tendons in patients with knee arthrosis: a comparative radiological study. J Diabetes Complications 2007;21(6): 392–396 Ilan DI, Tejwani N, Keschner M, Leibman M. Quadriceps tendon rupture. J Am Acad Orthop Surg 2003;11(3):192–200
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