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Extensor Mechanism Disruption After Contralateral Middle Third Patellar Tendon Harvest for Anterior Cruciate Ligament Revision Reconstruction
Case Report
Extensor Mechanism Disruption After Contralateral Middle Third Patellar Tendon Harvest for Anterior Cruciate Ligament Revision Reconstruction Benjamin T. Busfield, M.D., Marc R Safran, M.D., and W. Dilworth Cannon, M.D.
Abstract: The contralateral central third patellar tendon autograft is a reliable graft choice for revision, and recently, for primary reconstruction of the anterior cruciate ligament (ACL). We report 2 complications including a lateral third tibial tuberosity fracture and a distal patellar tendon avulsion with contralateral patellar tendon autograft with disruption of the extensor mechanism of the donor knee. A patient sustained a lateral tibial tuberosity fracture of the donor knee and underwent open reduction and internal fixation. At 1-year follow-up, she had no extensor lag and full range of motion. Another patient sustained a distal patellar tendon avulsion of the donor knee and underwent primary repair. Three years postoperatively, she had a full range of motion and no extensor lag. Although contralateral middle third patellar tendon autograft for primary and revision ACL reconstruction is established in the literature, extensor mechanism complications can occur. Technical considerations are important to avoid weakening the remaining patellar tendon insertion. Postoperative nerve blocks or local anesthetics may alter pain feedback for regulation of weight bearing and contribute to overload of the donor knee. Key Words: Extensor mechanism rupture—Anterior cruciate ligament—Revision—Contralateral autograft.
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evisions of failed anterior cruciate ligament (ACL) reconstructions are commonly performed for athletic individuals to allow return to recreational and athletic activities. Reconstruction of the ACL restores stability and offers protection of the menisci and articular cartilage. Patellar tendon allograft, Achilles allograft, hamstring autograft, ipsilateral and contralateral patellar tendon autograft, quadriceps ten-
From the Department of Orthopaedic Surgery, University of California, San Francisco, San Francisco, California, U.S.A. Address correspondence and reprint requests to Benjamin T. Busfield M.S., M.D., 500 Parnassus Ave, MU-320W, Box 0728, San Francisco, CA 94143-0728, U.S.A. © 2005 by the Arthroscopy Association of North America Cite this article as: Busfield BT, Safran MR, Cannon WD. Extensor mechanism disruption after contralateral middle third patellar tendon harvest for anterior cruciate ligament revision reconstruction. Arthroscopy 2005;21:1270.e1-1270.e6 [doi: 10.1016/j.arthro.2005.07.010]. 0749-8063/05/2110-4557$30.00/0 doi:10.1016/j.arthro.2005.07.010
don autograft, and reharvest of the patellar tendon have all been established as graft alternatives for reconstruction.1 Uribe et al.2 and Shelbourne et al.3,4 have reported acceptable results using contralateral patellar tendon autograft for primary and revision ACL reconstruction with minimal donor-site morbidity. In fact, Shelbourne and Urch3 have had excellent outcomes and minimal complications using contralateral patellar tendon autograft for primary ACL reconstruction. Contralateral middle third patellar tendon harvest offers the same advantages as ipsilateral patellar tendon autograft, but divides the surgical trauma between the 2 knees.5 Rehabilitation can be altered to benefit each knee individually and achieve faster recovery and return to activities. Potential intraoperative complications from harvesting the ipsilateral patellar tendon autograft include patellar fracture and avulsion of the patellar tendon from the inferior pole of the patella.6,7 Early postoperative complications include patellar tendon rupture,
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patellar tendonitis, quadriceps weakness, loss of full extension, and anterior knee pain.6,8-10 Patellar fractures have been described intraoperatively caused by bone plug harvest and postoperatively because of the presence of a stress riser.11 Tibial tuberosity and tibial plateau fractures as late postoperative complications at 6 weeks and 7 months postoperatively, respectively, have been reported for primary ACL reconstruction using the ipsilateral patellar tendon autograft.12,13 The fractures were related to trauma and the stress riser at the bone plug harvest site and the tibial tunnel, respectively.12,13 A patellar tendon avulsion was also reported 6 weeks postoperatively from primary ACL reconstruction with ipsilateral patellar tendon autograft from a mechanical fall.14 Despite the potential donor-site morbidity documented in the literature, very few complications have been reported with contralateral patellar tendon harvest for primary or revision ACL reconstruction. Shelbourne et al.3,4 have reported 1 graft rupture at 6 months, 8 cases of scarring causing loss of hyperextension, and 1 case of knee pain causing inability to return to sport. We present the first report of 2 patients with early postoperative donor-site extensor mechanism disruption from ACL revision reconstruction using contralateral middle third patellar tendon autograft resulting in a tibial tuberosity avulsion fracture and a patellar tendon avulsion from the tibial tuberosity.
CASE 1 A 5-ft 5-in, 150-lb 40-year-old woman presented with symptoms of left anteromedial and medial knee pain. Previous orthopaedic surgeries included a left ACL reconstruction with ipsilateral middle third patellar tendon graft in 1989 after a skiing injury. She ruptured her reconstructed left ACL in 1998 in another skiing accident. Arthroscopy was performed in 2000 and confirmed a ruptured ACL graft. Debridement of a cyclops lesion was also performed. The patient sustained another knee injury 2 months before her presentation in our clinic when she went to step down from a 3-ft height and lost her balance. She reported falling in an awkward position resulting in a twisting injury. Magnetic resonance imaging (MRI) revealed a medial meniscal tear and an absent ACL. Physical examination of her left knee revealed a 3⫹ Lachman test and 2⫹ pivot-shift. Her range of motion was symmetric from 2° to 140° and she developed atrophy of her left quadriceps. She complained of left knee pain during squatting. She had medial joint-line
FIGURE 1. Lateral radiograph from case 1 shows a minimally displaced tibial tuberosity fracture. The fracture propagates laterally from the corner of the lateral and distal tibial bone plug osteotomies.
tenderness and there was no evidence of patellar tendonitis bilaterally on physical examination. The patient underwent medial meniscal repair and revision ACL reconstruction using a contralateral central third patellar tendon autograft. The patient selected this graft as her preference after discussion of all the different graft options. The medial meniscus was repaired using the inside-out suture technique and the ACL was endoscopically reconstructed with the contralateral middle third patellar tendon graft. The central 10 mm of the patellar tendon was harvested, with the bone block from the tibial tubercle measuring 10 ⫻ 35 mm. The bone plug harvest was performed using a bone saw and osteotomes, and cuts were oriented to make a trapezoidal bone block. There were no complications during the procedure and a femoral nerve block was performed on the reconstructed knee for perioperative analgesia. No block was used on the donor knee. The patient was placed in bilateral hinged knee braces and was allowed full range of motion on the donor side. The patient was allowed full weightbearing bilaterally, but only in full extension on the reconstructed knee. At home the night after surgery, she noted a popping sound in her donor knee when pivoting to stand from a seated position from a stool. She developed increasing pain and inability to extend her knee. Radiographs revealed a minimally displaced tibial tuberosity fracture that extended laterally from the distal corner of the osteotomy site (Fig 1). Physical examination revealed a 2⫹ left knee effusion and the patient was unable to perform active knee extension.
EXTENSOR MECHANISM DISRUPTION Once the fracture was identified the patient underwent open reduction and internal fixation of the lateral tibial tuberosity fracture. A 4.5-mm interfragmentary screw supplemented with a tension band wire were placed after obtaining an anatomic reduction. The patient was placed in a knee brace postoperatively, locked in extension. She was allowed full weight bearing. Passive range-of-motion exercises were initiated after 1 week. At 6 weeks postoperatively, rehabilitation was continued with emphasis on quadriceps strengthening. Crutches were discontinued at 6 weeks. Radiographs of the right tibial tuberosity fracture at 4.5 months showed the tibial tuberosity avulsion fracture to be healed and the patient had no extensor lag and a full range of motion. At the 1-year follow-up, the patient had no complaints with either knee, and maintained full range of motion and no extensor lag in either knee. CASE 2 A 5-ft, 120-lb 39-year-old woman presented with right knee instability after undergoing a right ACL reconstruction with ipsilateral bone–patellar tendon– bone autograft in 1997. She continued to experience knee instability and significant medial knee pain that precluded cycling. On presentation 2 years postoperatively, physical examination revealed a 1-2⫹ Lachman test, 2⫹ pivot-shift, and a 2⫹ Losee test. There was a 7.5-mm difference measured by the Knee Laxity Tester (OSI, Union City, CA) with 40 lb of force. A preoperative MRI revealed a medial meniscal tear and an intact ACL. The patient elected to use contralateral bone–patellar tendon– bone autograft for her revision ACL reconstruction. Arthroscopy revealed a small medial meniscal tear that was not debrided. An 11.0-mm middle third bone–patellar tendon– bone graft was harvested from the contralateral knee. The tibial tuberosity bone plug was cut with a bone saw and was 11 mm wide and 25 mm long. The bone cuts were angled inward to create a trapezoidal bone plug. The patellar tendon defect was approximated with sutures. Revision reconstruction was done using the over-the-top technique and a femoral trough; 30 mL of 0.25% bupivacaine containing epinephrine was injected into both knees and incision sites. There were no complications during the surgery. While pivoting to a wheel chair from the gurney on her donor left knee on discharge from the postanesthesia recovery room, the patient experienced a pop in
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FIGURE 2. MRI sagittal cuts from case 2 showing disruption of the remaining patellar tendon at the tibial tuberosity insertion.
her knee. At home, she complained of increasing pain and inability to extend her knee. On examination 3 days postoperatively, she had a significant effusion and was unable to actively extend her knee. Radiographs showed patella alta without any fracture of the patella or tibial tuberosity. An MRI revealed an edematous wavy patellar tendon consistent with a complete patellar tendon avulsion from the tibial tuberosity (Fig 2). On postoperative day 8, the patient underwent repair of her avulsed left patellar tendon. Intraoperatively, the patellar tendon was found to be avulsed from the tibial tuberosity 5 to 7 mm on both sides of the harvest site. The medial and lateral patellar retinacula were completely intact. Two No. 5 Ethibond Krakow sutures (Ethicon, Somerville, NJ) were placed through 3 drill holes in the tibial tuberosity and the tendon was reapproximated to the insertion. The left lower extremity was placed into a hinged knee brace locked in full extension and the patient was allowed full weight bearing bilaterally. After 2 weeks, the patient was allowed progressively increased passive range of motion with full weight bearing. At 6 weeks, the patient began quadriceps rehabilitation for the donor knee. At the 3-year follow-up, the patient had good results for bilateral knees. She recovered preoperative range of motion bilaterally without extensor lag. She had no tenderness to palpation bilaterally. She had no donor knee pain and complains of mild bilateral medial knee pain. The patient denied experiencing any anterior knee pain or right knee instability and has been able to return to cycling.
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B. T. BUSFIELD ET AL. DISCUSSION
Very few complications have been reported for central third patellar tendon harvest from the contralateral knee despite the well-documented donor-site morbidity for the ipsilateral knee harvest for ACL reconstruction. One of the main arguments against using a contralateral patellar tendon autograft harvest for ACL reconstruction is that it violates the otherwise normal knee and traumatizes the primary postoperative weight-bearing pillar.1 However, Shelbourne and Urch3 suggest that contralateral middle third patellar tendon harvest lessens the trauma to the reconstructed knee and shortens the length of rehabilitation. Quadriceps strengthening can begin immediately postoperatively for the donor knee without stressing the ACL graft.4 A case report details marked quadriceps weakness in a bilateral ACL-deficient patient who underwent staged contralateral central third patellar tendon autograft ACL reconstruction to avoid further compromise of the extensor mechanism and the rehabilitation of the reconstructed knee.15 In a series of 54 patients undergoing ACL revision with contralateral patellar tendon autograft, Shelbourne and O’Shea4 reported a single complication of a graft rupture at 6 months while playing basketball. Rubinstein et al.9 reported on the contralateral donor knee morbidity for 20 patients, for 17 of whom revision ACL reconstruction was performed. Follow-up time ranged from 6 months to 5 years and 2 months with an average of 2 years. Quadriceps strength was 69%, 93%, and 95% compared with preoperative strength at 6 weeks, 1 year, and 2 years, respectively. Although 11 patients had patellar tendonitis that was “rarely restricting” and “not a problem” after 1 year, the surgical technique included a concomitant lateral release in over half of the patients.9 The lack of uniform surgical technique and the additional procedure (lateral release) make the conclusions of this study difficult to interpret. Uribe et al.2 performed ACL revision reconstruction with contralateral patellar tendon autograft in 17 of 54 patients. There was no decreased range of motion, quadriceps strength was 85% of baseline by 6 months, and there were no cases of patellar tendinitis or anterior knee pain at 1 year in the contralateral donor knee. Shelbourne and Urch3 reported the outcomes of a nonrandomized prospective study for primary ACL reconstruction in 228 patients with ipsilateral and 434 patients with contralateral middle third patellar tendon harvest. The reconstructed knee in the contralateral donor patients had greater flexion at 1 and 2 weeks, as
well as greater quadriceps strength at 1, 2, and 4 months postoperatively. Using the goal-directed rehabilitation program, the contralateral donor knee patients were able to progress more rapidly and return to sport at an average of 4.9 months compared with 6.1 months for the ipsilateral donor group. In the competitive patient subgroup, consisting of patients that presumably have a greater impetus to progress through rehabilitation, 63% versus 32% were able to return to sport at 4 months in the contralateral and ipsilateral groups, respectively.3 The Noyes subjective scores indicated equivalent patient satisfaction despite having surgery on both knees. Complications included scar resection to regain hyperextension in 5 contralateral and 3 ipsilateral donor reconstructed knees. Of note, 1 patient in the contralateral donor group could not return to sports because of pain from the donor site. No other patients had anterior knee pain that interfered with activities. The 2 complications in our study have not been documented in the literature for contralateral middle third patellar tendon harvest. There are only 2 case reports of proximal tibia fractures and 1 case report of a distal patellar tendon avulsion in the ipsilateral donor knee for primary ACL reconstruction. Moen et al.12 reported the case of a traumatic proximal tibial fracture 6 weeks postoperatively. The patient suffered a nondisplaced proximal tibial fracture through the edge of the tibial tuberosity osteotomy site after a mechanical fall and was treated in a long-leg cast without complication. Morgan and Steensen13 documented a nondisplaced lateral tibial plateau fracture in a patient 7 months postoperatively after a direct traumatic blow. The fracture extended into the tibial tunnel and the patient was restricted to non–weight-bearing in a hinged knee brace. The only case of a distal patellar tendon avulsion occurred 6 weeks postoperatively from a primary ACL reconstruction using ipsilateral patellar tendon autograft during a hyperflexion knee injury from a mechanical fall.14 The authors suggest that undermining the medial or lateral insertion sites of the patellar tendon onto the tibial tuberosity may cause weakness or necrosis of the tendon, in addition to creating a stress riser for avulsion fractures. They recommend harvesting triangular bone blocks to minimize the creation of any stress riser.14 In our case 1, the harvesting of the tibial bone plug likely undermined the lateral aspect of the tibial tuberosity, leading to an early postoperative fracture. This may have occurred by not accounting for the slope of the lateral tibial tuberosity when making the bone cuts. Sawing the
EXTENSOR MECHANISM DISRUPTION bone perpendicular to the extremity axis would lead to undermining the remaining lateral tibial tuberosity, as opposed to sawing perpendicular (or actually ⬎90°) to the posterolateral sloping tuberosity laterally. Technical considerations for harvesting both the patellar and the tibial tuberosity bone plug are similar in principle, given the similar osteotomies and creation of stress risers. In a report of patellar fractures as a complication of ACL reconstruction, there were 3 postoperative patellar fractures.11 Two of these patellar fractures occurred in the contralateral donor knee. Technical inaccuracies were implicated in most of these instances. The authors warn against overloading the contralateral donor knee when the patient limits weight bearing on the more painful reconstructed knee, which occurred in 2 of their cases and may have been a factor in our 2 complications. Although our patients were allowed weight bearing as tolerated bilaterally, restricting the reconstructed knee to weight bearing only in extension for case 1 may have increased the load borne on the contralateral lower extremity and the risk of extensor mechanism avulsion. A porcine model study measuring impact energy and repeat impact testing to fracture suggested that roundcornered osteotomies are superior in minimizing patellar stress risers, although trapezoidal were superior to sharp-cornered osteotomies.16 This study also found that sharp-cornered osteotomies with drill holes at the corners were superior to trapezoidal osteotomies. Round-cornered osteotomies were made using curved osteotomes, and extrapolating this study to human cadaveric biomechanical studies may provide insight into minimizing intraoperative and postoperative fractures. Our postoperative complications were likely attributable to a combination of technical factors and overload of the contralateral donor knee given the immediate postoperative time frame. Although the surgeons used osteotomes and a bone saw to create a trapezoidal bone plug at the tibial tuberosity, the remaining insertion of the patellar tendon may have been undermined. The patients’ pivoting motion on the contralateral donor leg likely created a torsional force that concentrated at the sharp-cornered osteotomy stress riser and created a fracture. Another possibility is that a quadriceps contraction while arising from a seated position resulted in an avulsion fracture. The postoperative nerve block on the reconstructed knee in case 1 may have altered the patient’s proprioception and contributed to higher stresses generated on the donor knee. The local anesthetic used in case 2 on bilateral knees may have blocked much of the pain inhibition
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feedback loop, resulting in overload of the donor knee. Although the extensor mechanism was not completely disrupted, given the intact medial third of the patellar tendon insertion in case 1, the lack of active knee extension and displacement of the fragment necessitated surgery. The combination of interfragmentary screw and tension band fixation provided rigid fixation to allow passive range-of-motion postoperatively. Revision reconstruction of the ACL with contralateral middle third patellar tendon autograft has been performed with excellent results and few complications. Primary ACL reconstruction with this graft source has also been shown to have outcomes that are arguably superior to ipsilateral middle third patellar tendon harvest. One must keep in mind the possible disastrous complications that can occur to the contralateral donor knee. Our 2 reported complications to the contralateral extensor mechanism necessitated further surgery, compromised mobility with postoperative bracing in extension of the donor knee, and added further rehabilitation time. Shelbourne may have few complications as a result of performing a high volume of contralateral central patellar tendon harvests, although the senior authors have performed the technique much more frequently for ipsilateral primary ACL reconstruction. The early time frame of our complications implicate surgical technique, postoperative analgesia, and weight bearing. Shelbourne uses ketorolac preoperatively and postoperatively and also infiltrates the contralateral donor knee wound with 25 mL of 0.25% bupivacaine.3 Postoperative analgesia in the form of an ipsilateral femoral nerve block in case 1 and bilateral intra-articular and wound infiltration with bupivacaine may have contributed to donor knee overload. In addition, taking an 11-cm graft in case 2 may be implicated in creating a stress riser from taking a large graft, although this was a third of the tendon width. Patients should be counseled regarding the possible extensor mechanism complications when the donor knee is used for autograft harvest. Both of our patients had excellent outcomes despite the early postoperative extensor mechanism disruptions, but prevention by good surgical technique and avoiding overload of the donor knee are paramount. REFERENCES 1. Ritchie JR, Parker RD. Graft selection in anterior cruciate ligament revision surgery. Clin Orthop 1996;325:65-77. 2. Uribe JW, Hechtman KS, Zvijac JE, Tjin-A-Tsoi EW. Revision anterior cruciate ligament surgery: Experience from Miami. Clin Orthop 1996;325:91-99.
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3. Shelbourne KD, Urch SE. Primary anterior cruciate ligament reconstruction using the contralateral autogenous patellar tendon. Am J Sports Med 2000;28:651-658. 4. Shelbourne KD, O’Shea JJ. Revision anterior cruciate ligament reconstruction using the contralateral bone–patellar tendon– bone graft. Instr Course Lect 2002;51:343-346. 5. Shelbourne KD. Accelerated rehabilitation after anterior cruciate ligament reconstruction. Am J Sports Med 1990;18:292299. 6. Allum, R. Aspects of current management—Complications of arthroscopic reconstruction of the anterior cruciate ligament. J Bone Joint Surg Br 2003;85:12-16. 7. Graf B, Uhr F. Complication of intra-articular anterior cruciate ligament reconstruction. Clin Sports Med 1988;7:835-848. 8. Kartus J, Stener S, Lindahl S, et al. Ipsi- or contralateral patellar tendon graft in anterior cruciate ligament revision surgery—A comparison of 2 methods. Am J Sports Med 1998; 26:499-504. 9. Rubinstein RA, Shelbourne KD, VanMeter CD, et al. Isolated autogenous bone–patellar tendon– bone graft site morbidity. Am J Sports Med 1994;22:324-327. 10. Sachs RA, Daniel DM, Stone ML. Patellofemoral problems
11. 12. 13. 14. 15. 16.
after anterior cruciate ligament reconstruction. Am J Sports Med 1989;17:760-765. Christen B, Jakob RP. Fractures associated with patellar ligament grafts in cruciate ligament surgery. J Bone Joint Surg Br 1992;74:617-619. Moen KY, Melbourne DB, Raasch WG. Fracture of the proximal tibia after anterior cruciate ligament reconstruction—A case report. Am J Orthop 1998;27:629-630. Morgan E, Steensen RN. Traumatic proximal tibial fracture following anterior cruciate ligament reconstruction. Am J Knee Surg 1998;11:193-194. Hardin GT, Bach BR. Distal rupture of the infrapatellar tendon after use of its central third for anterior cruciate ligament reconstruction. Am J Knee Surg 1992;5:140-143. Jari S, Shelbourne KD. Staged bilateral anterior cruciate ligament construction with use of contralateral patellar tendon autograft. Am J Sports Med 2002;30:437-440. Moholkar K, Taylor D, O’Reagan, M, et al. A biomechanical analysis of four different methods of harvesting bone–patellar tendon– bone graft in porcine knees. J Bone Joint Surg Am 2002;84:1782-1787.
Extensor Mechanism Disruption After Contralateral Middle Third Patellar Tendon Harvest for Anterior Cruciate Ligament Revision Reconstruction Benjamin T. Busfield, M.D., Marc R Safran, M.D., and W. Dilworth Cannon, M.D.
Abstract: The contralateral central third patellar tendon autograft is a reliable graft choice for revision, and recently, for primary reconstruction of the anterior cruciate ligament (ACL). We report 2 complications including a lateral third tibial tuberosity fracture and a distal patellar tendon avulsion with contralateral patellar tendon autograft with disruption of the extensor mechanism of the donor knee. A patient sustained a lateral tibial tuberosity fracture of the donor knee and underwent open reduction and internal fixation. At 1-year follow-up, she had no extensor lag and full range of motion. Another patient sustained a distal patellar tendon avulsion of the donor knee and underwent primary repair. Three years postoperatively, she had a full range of motion and no extensor lag. Although contralateral middle third patellar tendon autograft for primary and revision ACL reconstruction is established in the literature, extensor mechanism complications can occur. Technical considerations are important to avoid weakening the remaining patellar tendon insertion. Postoperative nerve blocks or local anesthetics may alter pain feedback for regulation of weight bearing and contribute to overload of the donor knee. Key Words: Extensor mechanism rupture—Anterior cruciate ligament—Revision—Contralateral autograft.
R
evisions of failed anterior cruciate ligament (ACL) reconstructions are commonly performed for athletic individuals to allow return to recreational and athletic activities. Reconstruction of the ACL restores stability and offers protection of the menisci and articular cartilage. Patellar tendon allograft, Achilles allograft, hamstring autograft, ipsilateral and contralateral patellar tendon autograft, quadriceps ten-
From the Department of Orthopaedic Surgery, University of California, San Francisco, San Francisco, California, U.S.A. Address correspondence and reprint requests to Benjamin T. Busfield M.S., M.D., 500 Parnassus Ave, MU-320W, Box 0728, San Francisco, CA 94143-0728, U.S.A. © 2005 by the Arthroscopy Association of North America Cite this article as: Busfield BT, Safran MR, Cannon WD. Extensor mechanism disruption after contralateral middle third patellar tendon harvest for anterior cruciate ligament revision reconstruction. Arthroscopy 2005;21:1270.e1-1270.e6 [doi: 10.1016/j.arthro.2005.07.010]. 0749-8063/05/2110-4557$30.00/0 doi:10.1016/j.arthro.2005.07.010
don autograft, and reharvest of the patellar tendon have all been established as graft alternatives for reconstruction.1 Uribe et al.2 and Shelbourne et al.3,4 have reported acceptable results using contralateral patellar tendon autograft for primary and revision ACL reconstruction with minimal donor-site morbidity. In fact, Shelbourne and Urch3 have had excellent outcomes and minimal complications using contralateral patellar tendon autograft for primary ACL reconstruction. Contralateral middle third patellar tendon harvest offers the same advantages as ipsilateral patellar tendon autograft, but divides the surgical trauma between the 2 knees.5 Rehabilitation can be altered to benefit each knee individually and achieve faster recovery and return to activities. Potential intraoperative complications from harvesting the ipsilateral patellar tendon autograft include patellar fracture and avulsion of the patellar tendon from the inferior pole of the patella.6,7 Early postoperative complications include patellar tendon rupture,
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patellar tendonitis, quadriceps weakness, loss of full extension, and anterior knee pain.6,8-10 Patellar fractures have been described intraoperatively caused by bone plug harvest and postoperatively because of the presence of a stress riser.11 Tibial tuberosity and tibial plateau fractures as late postoperative complications at 6 weeks and 7 months postoperatively, respectively, have been reported for primary ACL reconstruction using the ipsilateral patellar tendon autograft.12,13 The fractures were related to trauma and the stress riser at the bone plug harvest site and the tibial tunnel, respectively.12,13 A patellar tendon avulsion was also reported 6 weeks postoperatively from primary ACL reconstruction with ipsilateral patellar tendon autograft from a mechanical fall.14 Despite the potential donor-site morbidity documented in the literature, very few complications have been reported with contralateral patellar tendon harvest for primary or revision ACL reconstruction. Shelbourne et al.3,4 have reported 1 graft rupture at 6 months, 8 cases of scarring causing loss of hyperextension, and 1 case of knee pain causing inability to return to sport. We present the first report of 2 patients with early postoperative donor-site extensor mechanism disruption from ACL revision reconstruction using contralateral middle third patellar tendon autograft resulting in a tibial tuberosity avulsion fracture and a patellar tendon avulsion from the tibial tuberosity.
CASE 1 A 5-ft 5-in, 150-lb 40-year-old woman presented with symptoms of left anteromedial and medial knee pain. Previous orthopaedic surgeries included a left ACL reconstruction with ipsilateral middle third patellar tendon graft in 1989 after a skiing injury. She ruptured her reconstructed left ACL in 1998 in another skiing accident. Arthroscopy was performed in 2000 and confirmed a ruptured ACL graft. Debridement of a cyclops lesion was also performed. The patient sustained another knee injury 2 months before her presentation in our clinic when she went to step down from a 3-ft height and lost her balance. She reported falling in an awkward position resulting in a twisting injury. Magnetic resonance imaging (MRI) revealed a medial meniscal tear and an absent ACL. Physical examination of her left knee revealed a 3⫹ Lachman test and 2⫹ pivot-shift. Her range of motion was symmetric from 2° to 140° and she developed atrophy of her left quadriceps. She complained of left knee pain during squatting. She had medial joint-line
FIGURE 1. Lateral radiograph from case 1 shows a minimally displaced tibial tuberosity fracture. The fracture propagates laterally from the corner of the lateral and distal tibial bone plug osteotomies.
tenderness and there was no evidence of patellar tendonitis bilaterally on physical examination. The patient underwent medial meniscal repair and revision ACL reconstruction using a contralateral central third patellar tendon autograft. The patient selected this graft as her preference after discussion of all the different graft options. The medial meniscus was repaired using the inside-out suture technique and the ACL was endoscopically reconstructed with the contralateral middle third patellar tendon graft. The central 10 mm of the patellar tendon was harvested, with the bone block from the tibial tubercle measuring 10 ⫻ 35 mm. The bone plug harvest was performed using a bone saw and osteotomes, and cuts were oriented to make a trapezoidal bone block. There were no complications during the procedure and a femoral nerve block was performed on the reconstructed knee for perioperative analgesia. No block was used on the donor knee. The patient was placed in bilateral hinged knee braces and was allowed full range of motion on the donor side. The patient was allowed full weightbearing bilaterally, but only in full extension on the reconstructed knee. At home the night after surgery, she noted a popping sound in her donor knee when pivoting to stand from a seated position from a stool. She developed increasing pain and inability to extend her knee. Radiographs revealed a minimally displaced tibial tuberosity fracture that extended laterally from the distal corner of the osteotomy site (Fig 1). Physical examination revealed a 2⫹ left knee effusion and the patient was unable to perform active knee extension.
EXTENSOR MECHANISM DISRUPTION Once the fracture was identified the patient underwent open reduction and internal fixation of the lateral tibial tuberosity fracture. A 4.5-mm interfragmentary screw supplemented with a tension band wire were placed after obtaining an anatomic reduction. The patient was placed in a knee brace postoperatively, locked in extension. She was allowed full weight bearing. Passive range-of-motion exercises were initiated after 1 week. At 6 weeks postoperatively, rehabilitation was continued with emphasis on quadriceps strengthening. Crutches were discontinued at 6 weeks. Radiographs of the right tibial tuberosity fracture at 4.5 months showed the tibial tuberosity avulsion fracture to be healed and the patient had no extensor lag and a full range of motion. At the 1-year follow-up, the patient had no complaints with either knee, and maintained full range of motion and no extensor lag in either knee. CASE 2 A 5-ft, 120-lb 39-year-old woman presented with right knee instability after undergoing a right ACL reconstruction with ipsilateral bone–patellar tendon– bone autograft in 1997. She continued to experience knee instability and significant medial knee pain that precluded cycling. On presentation 2 years postoperatively, physical examination revealed a 1-2⫹ Lachman test, 2⫹ pivot-shift, and a 2⫹ Losee test. There was a 7.5-mm difference measured by the Knee Laxity Tester (OSI, Union City, CA) with 40 lb of force. A preoperative MRI revealed a medial meniscal tear and an intact ACL. The patient elected to use contralateral bone–patellar tendon– bone autograft for her revision ACL reconstruction. Arthroscopy revealed a small medial meniscal tear that was not debrided. An 11.0-mm middle third bone–patellar tendon– bone graft was harvested from the contralateral knee. The tibial tuberosity bone plug was cut with a bone saw and was 11 mm wide and 25 mm long. The bone cuts were angled inward to create a trapezoidal bone plug. The patellar tendon defect was approximated with sutures. Revision reconstruction was done using the over-the-top technique and a femoral trough; 30 mL of 0.25% bupivacaine containing epinephrine was injected into both knees and incision sites. There were no complications during the surgery. While pivoting to a wheel chair from the gurney on her donor left knee on discharge from the postanesthesia recovery room, the patient experienced a pop in
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FIGURE 2. MRI sagittal cuts from case 2 showing disruption of the remaining patellar tendon at the tibial tuberosity insertion.
her knee. At home, she complained of increasing pain and inability to extend her knee. On examination 3 days postoperatively, she had a significant effusion and was unable to actively extend her knee. Radiographs showed patella alta without any fracture of the patella or tibial tuberosity. An MRI revealed an edematous wavy patellar tendon consistent with a complete patellar tendon avulsion from the tibial tuberosity (Fig 2). On postoperative day 8, the patient underwent repair of her avulsed left patellar tendon. Intraoperatively, the patellar tendon was found to be avulsed from the tibial tuberosity 5 to 7 mm on both sides of the harvest site. The medial and lateral patellar retinacula were completely intact. Two No. 5 Ethibond Krakow sutures (Ethicon, Somerville, NJ) were placed through 3 drill holes in the tibial tuberosity and the tendon was reapproximated to the insertion. The left lower extremity was placed into a hinged knee brace locked in full extension and the patient was allowed full weight bearing bilaterally. After 2 weeks, the patient was allowed progressively increased passive range of motion with full weight bearing. At 6 weeks, the patient began quadriceps rehabilitation for the donor knee. At the 3-year follow-up, the patient had good results for bilateral knees. She recovered preoperative range of motion bilaterally without extensor lag. She had no tenderness to palpation bilaterally. She had no donor knee pain and complains of mild bilateral medial knee pain. The patient denied experiencing any anterior knee pain or right knee instability and has been able to return to cycling.
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B. T. BUSFIELD ET AL. DISCUSSION
Very few complications have been reported for central third patellar tendon harvest from the contralateral knee despite the well-documented donor-site morbidity for the ipsilateral knee harvest for ACL reconstruction. One of the main arguments against using a contralateral patellar tendon autograft harvest for ACL reconstruction is that it violates the otherwise normal knee and traumatizes the primary postoperative weight-bearing pillar.1 However, Shelbourne and Urch3 suggest that contralateral middle third patellar tendon harvest lessens the trauma to the reconstructed knee and shortens the length of rehabilitation. Quadriceps strengthening can begin immediately postoperatively for the donor knee without stressing the ACL graft.4 A case report details marked quadriceps weakness in a bilateral ACL-deficient patient who underwent staged contralateral central third patellar tendon autograft ACL reconstruction to avoid further compromise of the extensor mechanism and the rehabilitation of the reconstructed knee.15 In a series of 54 patients undergoing ACL revision with contralateral patellar tendon autograft, Shelbourne and O’Shea4 reported a single complication of a graft rupture at 6 months while playing basketball. Rubinstein et al.9 reported on the contralateral donor knee morbidity for 20 patients, for 17 of whom revision ACL reconstruction was performed. Follow-up time ranged from 6 months to 5 years and 2 months with an average of 2 years. Quadriceps strength was 69%, 93%, and 95% compared with preoperative strength at 6 weeks, 1 year, and 2 years, respectively. Although 11 patients had patellar tendonitis that was “rarely restricting” and “not a problem” after 1 year, the surgical technique included a concomitant lateral release in over half of the patients.9 The lack of uniform surgical technique and the additional procedure (lateral release) make the conclusions of this study difficult to interpret. Uribe et al.2 performed ACL revision reconstruction with contralateral patellar tendon autograft in 17 of 54 patients. There was no decreased range of motion, quadriceps strength was 85% of baseline by 6 months, and there were no cases of patellar tendinitis or anterior knee pain at 1 year in the contralateral donor knee. Shelbourne and Urch3 reported the outcomes of a nonrandomized prospective study for primary ACL reconstruction in 228 patients with ipsilateral and 434 patients with contralateral middle third patellar tendon harvest. The reconstructed knee in the contralateral donor patients had greater flexion at 1 and 2 weeks, as
well as greater quadriceps strength at 1, 2, and 4 months postoperatively. Using the goal-directed rehabilitation program, the contralateral donor knee patients were able to progress more rapidly and return to sport at an average of 4.9 months compared with 6.1 months for the ipsilateral donor group. In the competitive patient subgroup, consisting of patients that presumably have a greater impetus to progress through rehabilitation, 63% versus 32% were able to return to sport at 4 months in the contralateral and ipsilateral groups, respectively.3 The Noyes subjective scores indicated equivalent patient satisfaction despite having surgery on both knees. Complications included scar resection to regain hyperextension in 5 contralateral and 3 ipsilateral donor reconstructed knees. Of note, 1 patient in the contralateral donor group could not return to sports because of pain from the donor site. No other patients had anterior knee pain that interfered with activities. The 2 complications in our study have not been documented in the literature for contralateral middle third patellar tendon harvest. There are only 2 case reports of proximal tibia fractures and 1 case report of a distal patellar tendon avulsion in the ipsilateral donor knee for primary ACL reconstruction. Moen et al.12 reported the case of a traumatic proximal tibial fracture 6 weeks postoperatively. The patient suffered a nondisplaced proximal tibial fracture through the edge of the tibial tuberosity osteotomy site after a mechanical fall and was treated in a long-leg cast without complication. Morgan and Steensen13 documented a nondisplaced lateral tibial plateau fracture in a patient 7 months postoperatively after a direct traumatic blow. The fracture extended into the tibial tunnel and the patient was restricted to non–weight-bearing in a hinged knee brace. The only case of a distal patellar tendon avulsion occurred 6 weeks postoperatively from a primary ACL reconstruction using ipsilateral patellar tendon autograft during a hyperflexion knee injury from a mechanical fall.14 The authors suggest that undermining the medial or lateral insertion sites of the patellar tendon onto the tibial tuberosity may cause weakness or necrosis of the tendon, in addition to creating a stress riser for avulsion fractures. They recommend harvesting triangular bone blocks to minimize the creation of any stress riser.14 In our case 1, the harvesting of the tibial bone plug likely undermined the lateral aspect of the tibial tuberosity, leading to an early postoperative fracture. This may have occurred by not accounting for the slope of the lateral tibial tuberosity when making the bone cuts. Sawing the
EXTENSOR MECHANISM DISRUPTION bone perpendicular to the extremity axis would lead to undermining the remaining lateral tibial tuberosity, as opposed to sawing perpendicular (or actually ⬎90°) to the posterolateral sloping tuberosity laterally. Technical considerations for harvesting both the patellar and the tibial tuberosity bone plug are similar in principle, given the similar osteotomies and creation of stress risers. In a report of patellar fractures as a complication of ACL reconstruction, there were 3 postoperative patellar fractures.11 Two of these patellar fractures occurred in the contralateral donor knee. Technical inaccuracies were implicated in most of these instances. The authors warn against overloading the contralateral donor knee when the patient limits weight bearing on the more painful reconstructed knee, which occurred in 2 of their cases and may have been a factor in our 2 complications. Although our patients were allowed weight bearing as tolerated bilaterally, restricting the reconstructed knee to weight bearing only in extension for case 1 may have increased the load borne on the contralateral lower extremity and the risk of extensor mechanism avulsion. A porcine model study measuring impact energy and repeat impact testing to fracture suggested that roundcornered osteotomies are superior in minimizing patellar stress risers, although trapezoidal were superior to sharp-cornered osteotomies.16 This study also found that sharp-cornered osteotomies with drill holes at the corners were superior to trapezoidal osteotomies. Round-cornered osteotomies were made using curved osteotomes, and extrapolating this study to human cadaveric biomechanical studies may provide insight into minimizing intraoperative and postoperative fractures. Our postoperative complications were likely attributable to a combination of technical factors and overload of the contralateral donor knee given the immediate postoperative time frame. Although the surgeons used osteotomes and a bone saw to create a trapezoidal bone plug at the tibial tuberosity, the remaining insertion of the patellar tendon may have been undermined. The patients’ pivoting motion on the contralateral donor leg likely created a torsional force that concentrated at the sharp-cornered osteotomy stress riser and created a fracture. Another possibility is that a quadriceps contraction while arising from a seated position resulted in an avulsion fracture. The postoperative nerve block on the reconstructed knee in case 1 may have altered the patient’s proprioception and contributed to higher stresses generated on the donor knee. The local anesthetic used in case 2 on bilateral knees may have blocked much of the pain inhibition
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feedback loop, resulting in overload of the donor knee. Although the extensor mechanism was not completely disrupted, given the intact medial third of the patellar tendon insertion in case 1, the lack of active knee extension and displacement of the fragment necessitated surgery. The combination of interfragmentary screw and tension band fixation provided rigid fixation to allow passive range-of-motion postoperatively. Revision reconstruction of the ACL with contralateral middle third patellar tendon autograft has been performed with excellent results and few complications. Primary ACL reconstruction with this graft source has also been shown to have outcomes that are arguably superior to ipsilateral middle third patellar tendon harvest. One must keep in mind the possible disastrous complications that can occur to the contralateral donor knee. Our 2 reported complications to the contralateral extensor mechanism necessitated further surgery, compromised mobility with postoperative bracing in extension of the donor knee, and added further rehabilitation time. Shelbourne may have few complications as a result of performing a high volume of contralateral central patellar tendon harvests, although the senior authors have performed the technique much more frequently for ipsilateral primary ACL reconstruction. The early time frame of our complications implicate surgical technique, postoperative analgesia, and weight bearing. Shelbourne uses ketorolac preoperatively and postoperatively and also infiltrates the contralateral donor knee wound with 25 mL of 0.25% bupivacaine.3 Postoperative analgesia in the form of an ipsilateral femoral nerve block in case 1 and bilateral intra-articular and wound infiltration with bupivacaine may have contributed to donor knee overload. In addition, taking an 11-cm graft in case 2 may be implicated in creating a stress riser from taking a large graft, although this was a third of the tendon width. Patients should be counseled regarding the possible extensor mechanism complications when the donor knee is used for autograft harvest. Both of our patients had excellent outcomes despite the early postoperative extensor mechanism disruptions, but prevention by good surgical technique and avoiding overload of the donor knee are paramount. REFERENCES 1. Ritchie JR, Parker RD. Graft selection in anterior cruciate ligament revision surgery. Clin Orthop 1996;325:65-77. 2. Uribe JW, Hechtman KS, Zvijac JE, Tjin-A-Tsoi EW. Revision anterior cruciate ligament surgery: Experience from Miami. Clin Orthop 1996;325:91-99.
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3. Shelbourne KD, Urch SE. Primary anterior cruciate ligament reconstruction using the contralateral autogenous patellar tendon. Am J Sports Med 2000;28:651-658. 4. Shelbourne KD, O’Shea JJ. Revision anterior cruciate ligament reconstruction using the contralateral bone–patellar tendon– bone graft. Instr Course Lect 2002;51:343-346. 5. Shelbourne KD. Accelerated rehabilitation after anterior cruciate ligament reconstruction. Am J Sports Med 1990;18:292299. 6. Allum, R. Aspects of current management—Complications of arthroscopic reconstruction of the anterior cruciate ligament. J Bone Joint Surg Br 2003;85:12-16. 7. Graf B, Uhr F. Complication of intra-articular anterior cruciate ligament reconstruction. Clin Sports Med 1988;7:835-848. 8. Kartus J, Stener S, Lindahl S, et al. Ipsi- or contralateral patellar tendon graft in anterior cruciate ligament revision surgery—A comparison of 2 methods. Am J Sports Med 1998; 26:499-504. 9. Rubinstein RA, Shelbourne KD, VanMeter CD, et al. Isolated autogenous bone–patellar tendon– bone graft site morbidity. Am J Sports Med 1994;22:324-327. 10. Sachs RA, Daniel DM, Stone ML. Patellofemoral problems
11. 12. 13. 14. 15. 16.
after anterior cruciate ligament reconstruction. Am J Sports Med 1989;17:760-765. Christen B, Jakob RP. Fractures associated with patellar ligament grafts in cruciate ligament surgery. J Bone Joint Surg Br 1992;74:617-619. Moen KY, Melbourne DB, Raasch WG. Fracture of the proximal tibia after anterior cruciate ligament reconstruction—A case report. Am J Orthop 1998;27:629-630. Morgan E, Steensen RN. Traumatic proximal tibial fracture following anterior cruciate ligament reconstruction. Am J Knee Surg 1998;11:193-194. Hardin GT, Bach BR. Distal rupture of the infrapatellar tendon after use of its central third for anterior cruciate ligament reconstruction. Am J Knee Surg 1992;5:140-143. Jari S, Shelbourne KD. Staged bilateral anterior cruciate ligament construction with use of contralateral patellar tendon autograft. Am J Sports Med 2002;30:437-440. Moholkar K, Taylor D, O’Reagan, M, et al. A biomechanical analysis of four different methods of harvesting bone–patellar tendon– bone graft in porcine knees. J Bone Joint Surg Am 2002;84:1782-1787.