Technical Notes
Lateral Patellotibial Ligament Reconstruction for Medial Patellar Instability Gregory A. Sawyer, M.D., Tyler Cram, M.A., A.T.C., O.T.C., and Robert F. LaPrade, M.D., Ph.D.
Abstract: Medial patellar instability, though infrequently recognized, can be a disabling complication of a lateral retinacular release. Patients with persistent anterior knee pain and instability after lateral release should be evaluated closely. If evidence of increased medial patellar translation is identified on physical examination, a trial of reverse McConnell taping should be prescribed. If there is noted improvement in symptoms after this taping trial, reconstruction of the lateral patellotibial ligament should be considered. This article details our technique for lateral patellotibial ligament reconstruction using iliotibial band and patellar tendon autografts.
L
ateral patellar instability most frequently occurs in the female adolescent population after an acute traumatic event.1 Although the gold standard for treatment after a primary dislocation event is conservative management, a recurrence rate of 15% to 44% has been reported.2,3 When conservative management is unsuccessful, surgical intervention is recommended to restore stability to the patellofemoral joint. In the 1970s, lateral retinacular release became a popular treatment for lateral patellar instability and lateral patellar compression syndrome. It was believed that tight lateral retinacular tissues predisposed patients to subluxation or dislocation and compressed the patella against the lateral trochlear facet.4 However, an overly aggressive lateral release can compromise the major static and dynamic restraints to medial patellar excursion. These structures include the lateral patellotibial ligament and the lateral epicondylopatellar ligament.5 First recognized by Hughston and Deese,6 one of the major complications of lateral retinacular release is
From the Steadman Philippon Research Institute (G.A.S.); and The Steadman Clinic (T.C., R.F.L.), Vail, Colorado, U.S.A. The authors report the following potential conflict of interest or source of funding: R.F.L. receives support from Smith & Nephew, Arthrex, Health East Norway. Received May 14, 2014; accepted June 4, 2014. Address correspondence to Robert F. LaPrade, M.D., Ph.D., Steadman Philippon Research Institute, 181 W Meadow Dr, Ste 1000, Vail, CO 81657, U.S.A. E-mail: [email protected] Ó 2014 by the Arthroscopy Association of North America 2212-6287/14416/$36.00 http://dx.doi.org/10.1016/j.eats.2014.06.002
medial patellar instability caused by sectioning of the important lateral structures. In their investigation they evaluated 54 patients (60 knees) that were referred for failed lateral retinacular release procedures. Disabling medial patellar subluxation was identified postoperatively in 30 knees (50%); none of these patients had such complaints preoperatively. Shellock et al.7 subsequently performed a radiologic study using magnetic resonance imaging to evaluate the position of the patella within the trochlear groove at varying degrees of flexion in 130 patients. Of the 14 patients who had undergone a previous lateral retinacular release, 13 (93%) showed a medially positioned patella within the trochlear groove. The diagnosis of medial patellar instability is primarily clinical in nature, with physical examination findings consisting of increased medial patellar translation compared with the contralateral extremity and reproducible pain with this maneuver. When the diagnosis is suspected, patients should undergo a 6-week trial of physical therapistesupervised reverse McConnell taping so that the diagnosis can be confirmed (Fig 1). Patients who have significant relief of their symptoms with this modality are candidates for lateral ligament reconstruction. Although lateral patellar instability is well recognized, there is a paucity of literature describing the diagnosis and treatment of medial patellar instability. The purpose of this report is to describe our surgical technique for correction of medial patellar subluxation by reconstructing the lateral patellotibial ligament with autograft from the patellar tendon and the iliotibial band.
Arthroscopy Techniques, Vol 3, No 5 (October), 2014: pp e547-e550
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G. A. SAWYER ET AL.
Fig 1. Technique for application of reverse McConnell taping on a patient’s right knee. (L, lateral; M, medial; P, patella.)
Surgical Technique Patient Positioning and Examination Under Anesthesia The patient is placed in the supine position on the operating table (Video 1). After induction of general anesthesia, a bilateral examination with the patient under anesthesia is performed to confirm the diagnosis of medial patellar instability, as well as assess for crepitus and knee range of motion. A well-padded highthigh tourniquet is subsequently placed. Surgical Approach After administration of preoperative antibiotics, the reconstruction incision is made first to identify anatomic structures before fluid extravasation with arthroscopy and ensure that proper balance can be achieved for the reconstructive procedure. The incision is made from a location approximately 3 cm lateral and proximal to the patella to 3 cm distal to the Gerdy
tubercle. Sharp dissection is performed through the subcutaneous tissue to the level of the iliotibial band. The dissection is carried anteriorly to identify the lateral aspect of the patellar tendon. Graft Harvest The 2 grafts are subsequently harvested. The lateral 8 mm of the patellar tendon is harvested off the tibial tubercle, leaving its proximal patellar attachment (Fig 2). A central 8-mm-wide iliotibial band graft is then harvested, leaving its attachment to the Gerdy tubercle (Fig 2). This graft must be, at a minimum, equal to the length of the patellar tendon graft but generally measures approximately 70 mm. Tag sutures are placed in the free ends of each graft for manipulation and tensioning. A tunnel is created in the scar tissue along the normal course of the lateral patellotibial ligament, and both grafts are passed through the tunnel. The defect in the iliotibial band is then closed with interrupted No. 0 Vicryl suture (Ethicon,
Fig 2. Graft harvest of (A) patellar tendon and (B) iliotibial band in a patient’s right knee in the supine position.
LATERAL PATELLOTIBIAL LIGAMENT RECONSTRUCTION
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Fig 3. (A) Alignment of patellar tendon and iliotibial band grafts and (B) suture placement for tying grafts to one another in a patient’s right knee in the supine position.
Somerville, NJ) in horizontal mattress fashion before ligament reconstruction. Arthroscopy Routine arthroscopy is performed through standard anterolateral and anteromedial portals to assess the articular cartilage of the patellofemoral joint. A dynamic patellofemoral examination is performed to observe and document medial patellar subluxation. The fluid is then evacuated from the joint before proceeding with ligament reconstruction. Ligament Reconstruction The 2 grafts are tied together with No. 2 Orthocord suture (DePuy, Warsaw, IN) with the knee in full extension and the patella being held centrally in the trochlear groove (Fig 3). The patellar tendon should also be at its normal length. The grafts are tied proximally and distally when it has been validated that medial instability has been eliminated and that there is no evidence of lateral translation. Additional sutures are placed along the graft margins to ensure stability. Table 1 shows tips and pitfalls for this technique. Closure The tourniquet is let down and hemostasis achieved. The subcutaneous tissue is then closed in layers, and the skin is closed with a running subcuticular No. 4-0 Monocryl stitch (Ethicon). The arthroscopy portals are closed with No. 4-0 Monocryl. Steri-Strips (3M,
St Paul, MN) are loosely applied, followed by application of a sterile dressing and a knee immobilizer in full extension. Postoperative Rehabilitation The patient is admitted overnight for pain control and given aspirin for deep venous thrombosis prophylaxis. Touch-down weight bearing is allowed for the first 6 weeks in a knee immobilizer. Patients can remove the knee immobilizer for range-of-motion exercises, with active flexion and passive extension of 0 to 90 initiated on postoperative day 1. Patellar mobilization maneuvers in therapy are limited to the proximal and distal directions, whereas medial and lateral patellar mobility should be avoided to protect the newly reconstructed graft. Physical therapy is very important for quadriceps activation, edema control, and range of motion. After 6 weeks, the immobilizer can be discontinued and patients can wean off crutches once able to ambulate without a limp.
Discussion Medial patellar instability, though occurring much less frequently than its lateral counterpart, can be a painful and disabling condition. After the first description of this condition by Hughston and Deese6 in 1988, Nonweiler and DeLee8 reported their experience in 5 patients with medial subluxation after lateral release. Subsequent conservative treatment measures failed in these patients, and they required operative intervention.
Table 1. Tips and Pitfalls to Consider During Lateral Patellotibial Ligament Reconstruction Tips Perform open incision before arthroscopy to prevent distortion of normal anatomy. Measure length of patellar tendon graft, and make sure IT band graft is of same length or greater. Dissect posteriorly along IT band during initial dissection because anterior aspect is often distorted and retracted from previous release. Make sure patellar tendon is not pulled too far distally to create iatrogenic patella baja when tightening grafts. Pitfalls Holding patella centrally while tying grafts can be challenging. Surgeon must avoid overtightening, which can result in lateral subluxation, patella baja, or over-constraining of patellofemoral joint. IT, iliotibial.
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G. A. SAWYER ET AL.
After identification of the aforementioned condition, Hughston et al.9 developed multiple surgical techniques to correct it. They described 63 patients (65 knees) who underwent surgical correction of medial subluxation from 1984-1990. Fifty-eight knees (89%) had undergone previous lateral retinacular release. A direct repair technique was used in 39 knees (60%), whereas the remainder underwent lateral patellotibial reconstruction using either a slip of patellar tendon or iliotibial band or a combination of these 2 donor sites. The authors reported that 68% of patients had improvement in functional outcome scores and 75% had subjective improvement at 54 months’ follow-up. They also noted a significant procedural learning curve, with improved subjective patient outcomes in the second half of the study block. Teitge and Torga Spak10 described a technique used in 60 patients for lateral patellofemoral ligament reconstruction using a quadriceps tendon autograft with reported excellent results. In 2007 Shannon and Keene11 described arthroscopic medial retinacular release for treatment of medial patellar instability in 7 patients (9 knees). They reported no further instability and reported excellent results in 6 knees and good results in 3 knees based on the Merchant and Mercer12 criteria. We have attempted several different techniques; the surgical intervention for medial patellar instability preferred by Hughston et al.9 is similar to our described technique using a slip of both patellar tendon and iliotibial band to reconstruct the lateral patellotibial ligament. This technique provides a dynamic restraint to medial patellar subluxation. Similar to medial patellofemoral ligament reconstruction, gauging tension of the reconstruction can be challenging. The surgeon must avoid overtightening, which could result in lateral patellar instability and patella baja. Other potential risks associated with this procedure include patellar tendon rupture due to graft harvest and recurrent medial instability if the graft does not heal. This technique is contraindicated in patients who have undergone a previous surgical intervention involving the patellar tendon, including boneepatellar tendonebone autograft for anterior cruciate ligament reconstruction, tibial tubercle osteotomy, and patellar tendon repair.
The described surgical technique has provided an effective solution for patients with iatrogenic medial patellar subluxation after lateral release. We have not encountered any significant postoperative complications and have anecdotally noted improvements in patient satisfaction and functional outcomes. We are currently compiling 2-year patient outcomes to further evaluate the success of this procedure.
Acknowledgment The authors acknowledge Barry Eckhaus for his outstanding production of the surgical technique video.
References 1. Fithian DC, Paxton EW, Stone ML, et al. Epidemiology and natural history of acute patellar dislocation. Am J Sports Med 2004;32:1114-1121. 2. Hawkins RJ, Bell RH, Anisette G. Acute patellar dislocations. Am J Sports Med 1986;14:117-120. 3. Cofield FH, Bryan RS. Acute dislocation of the patella: Results of conservative treatment. J Trauma 1977;17:526-531. 4. Fithian DC, Pacton EW, Cohen AB. Indication in the treatment of patellar instability. J Knee Surg 2004;17:47-56. 5. Fu FH, Maday MG. Arthroscopic lateral release and the lateral patellar compression syndrome. Orthop Clin North Am 1992;23:601-612. 6. Hughston J, Deese M. Medial subluxation of the patella as a complication of lateral retinacular release. Am J Sports Med 1988;16:383-388. 7. Shellock FG, Jerrold MH, Deutsch AL, Fox JM. Patellar tracking abnormalities: Clinical experience with kinematic MR imaging in 130 patients. Radiology 1989;172:799-804. 8. Nonweiler DE, DeLee JC. The diagnosis and treatment of medial subluxation of the patella after lateral retinacular release. Am J Sports Med 1994;22:680-686. 9. Hughston JC, Flandry F, Brinker MR, Terry GC, Mills JC. Surgical correction of medial subluxation of the patella. Am J Sports Med 1996;24:486-491. 10. Teitge RA, Torga Spak R. Lateral patellofemoral ligament reconstruction. Arthroscopy 2004;20:998-1002. 11. Shannon BD, Keene JS. Results of arthroscopic medial retinacular release for treatment of medial subluxation of the patella. Am J Sports Med 2007;35:1180-1187. 12. Merchant AC, Mercer RL. Lateral release of the patella. Clin Orthop Relat Res 1974;103:40-45.
Lateral Patellotibial Ligament Reconstruction for Medial Patellar Instability Gregory A. Sawyer, M.D., Tyler Cram, M.A., A.T.C., O.T.C., and Robert F. LaPrade, M.D., Ph.D.
Abstract: Medial patellar instability, though infrequently recognized, can be a disabling complication of a lateral retinacular release. Patients with persistent anterior knee pain and instability after lateral release should be evaluated closely. If evidence of increased medial patellar translation is identified on physical examination, a trial of reverse McConnell taping should be prescribed. If there is noted improvement in symptoms after this taping trial, reconstruction of the lateral patellotibial ligament should be considered. This article details our technique for lateral patellotibial ligament reconstruction using iliotibial band and patellar tendon autografts.
L
ateral patellar instability most frequently occurs in the female adolescent population after an acute traumatic event.1 Although the gold standard for treatment after a primary dislocation event is conservative management, a recurrence rate of 15% to 44% has been reported.2,3 When conservative management is unsuccessful, surgical intervention is recommended to restore stability to the patellofemoral joint. In the 1970s, lateral retinacular release became a popular treatment for lateral patellar instability and lateral patellar compression syndrome. It was believed that tight lateral retinacular tissues predisposed patients to subluxation or dislocation and compressed the patella against the lateral trochlear facet.4 However, an overly aggressive lateral release can compromise the major static and dynamic restraints to medial patellar excursion. These structures include the lateral patellotibial ligament and the lateral epicondylopatellar ligament.5 First recognized by Hughston and Deese,6 one of the major complications of lateral retinacular release is
From the Steadman Philippon Research Institute (G.A.S.); and The Steadman Clinic (T.C., R.F.L.), Vail, Colorado, U.S.A. The authors report the following potential conflict of interest or source of funding: R.F.L. receives support from Smith & Nephew, Arthrex, Health East Norway. Received May 14, 2014; accepted June 4, 2014. Address correspondence to Robert F. LaPrade, M.D., Ph.D., Steadman Philippon Research Institute, 181 W Meadow Dr, Ste 1000, Vail, CO 81657, U.S.A. E-mail: [email protected] Ó 2014 by the Arthroscopy Association of North America 2212-6287/14416/$36.00 http://dx.doi.org/10.1016/j.eats.2014.06.002
medial patellar instability caused by sectioning of the important lateral structures. In their investigation they evaluated 54 patients (60 knees) that were referred for failed lateral retinacular release procedures. Disabling medial patellar subluxation was identified postoperatively in 30 knees (50%); none of these patients had such complaints preoperatively. Shellock et al.7 subsequently performed a radiologic study using magnetic resonance imaging to evaluate the position of the patella within the trochlear groove at varying degrees of flexion in 130 patients. Of the 14 patients who had undergone a previous lateral retinacular release, 13 (93%) showed a medially positioned patella within the trochlear groove. The diagnosis of medial patellar instability is primarily clinical in nature, with physical examination findings consisting of increased medial patellar translation compared with the contralateral extremity and reproducible pain with this maneuver. When the diagnosis is suspected, patients should undergo a 6-week trial of physical therapistesupervised reverse McConnell taping so that the diagnosis can be confirmed (Fig 1). Patients who have significant relief of their symptoms with this modality are candidates for lateral ligament reconstruction. Although lateral patellar instability is well recognized, there is a paucity of literature describing the diagnosis and treatment of medial patellar instability. The purpose of this report is to describe our surgical technique for correction of medial patellar subluxation by reconstructing the lateral patellotibial ligament with autograft from the patellar tendon and the iliotibial band.
Arthroscopy Techniques, Vol 3, No 5 (October), 2014: pp e547-e550
e547
e548
G. A. SAWYER ET AL.
Fig 1. Technique for application of reverse McConnell taping on a patient’s right knee. (L, lateral; M, medial; P, patella.)
Surgical Technique Patient Positioning and Examination Under Anesthesia The patient is placed in the supine position on the operating table (Video 1). After induction of general anesthesia, a bilateral examination with the patient under anesthesia is performed to confirm the diagnosis of medial patellar instability, as well as assess for crepitus and knee range of motion. A well-padded highthigh tourniquet is subsequently placed. Surgical Approach After administration of preoperative antibiotics, the reconstruction incision is made first to identify anatomic structures before fluid extravasation with arthroscopy and ensure that proper balance can be achieved for the reconstructive procedure. The incision is made from a location approximately 3 cm lateral and proximal to the patella to 3 cm distal to the Gerdy
tubercle. Sharp dissection is performed through the subcutaneous tissue to the level of the iliotibial band. The dissection is carried anteriorly to identify the lateral aspect of the patellar tendon. Graft Harvest The 2 grafts are subsequently harvested. The lateral 8 mm of the patellar tendon is harvested off the tibial tubercle, leaving its proximal patellar attachment (Fig 2). A central 8-mm-wide iliotibial band graft is then harvested, leaving its attachment to the Gerdy tubercle (Fig 2). This graft must be, at a minimum, equal to the length of the patellar tendon graft but generally measures approximately 70 mm. Tag sutures are placed in the free ends of each graft for manipulation and tensioning. A tunnel is created in the scar tissue along the normal course of the lateral patellotibial ligament, and both grafts are passed through the tunnel. The defect in the iliotibial band is then closed with interrupted No. 0 Vicryl suture (Ethicon,
Fig 2. Graft harvest of (A) patellar tendon and (B) iliotibial band in a patient’s right knee in the supine position.
LATERAL PATELLOTIBIAL LIGAMENT RECONSTRUCTION
e549
Fig 3. (A) Alignment of patellar tendon and iliotibial band grafts and (B) suture placement for tying grafts to one another in a patient’s right knee in the supine position.
Somerville, NJ) in horizontal mattress fashion before ligament reconstruction. Arthroscopy Routine arthroscopy is performed through standard anterolateral and anteromedial portals to assess the articular cartilage of the patellofemoral joint. A dynamic patellofemoral examination is performed to observe and document medial patellar subluxation. The fluid is then evacuated from the joint before proceeding with ligament reconstruction. Ligament Reconstruction The 2 grafts are tied together with No. 2 Orthocord suture (DePuy, Warsaw, IN) with the knee in full extension and the patella being held centrally in the trochlear groove (Fig 3). The patellar tendon should also be at its normal length. The grafts are tied proximally and distally when it has been validated that medial instability has been eliminated and that there is no evidence of lateral translation. Additional sutures are placed along the graft margins to ensure stability. Table 1 shows tips and pitfalls for this technique. Closure The tourniquet is let down and hemostasis achieved. The subcutaneous tissue is then closed in layers, and the skin is closed with a running subcuticular No. 4-0 Monocryl stitch (Ethicon). The arthroscopy portals are closed with No. 4-0 Monocryl. Steri-Strips (3M,
St Paul, MN) are loosely applied, followed by application of a sterile dressing and a knee immobilizer in full extension. Postoperative Rehabilitation The patient is admitted overnight for pain control and given aspirin for deep venous thrombosis prophylaxis. Touch-down weight bearing is allowed for the first 6 weeks in a knee immobilizer. Patients can remove the knee immobilizer for range-of-motion exercises, with active flexion and passive extension of 0 to 90 initiated on postoperative day 1. Patellar mobilization maneuvers in therapy are limited to the proximal and distal directions, whereas medial and lateral patellar mobility should be avoided to protect the newly reconstructed graft. Physical therapy is very important for quadriceps activation, edema control, and range of motion. After 6 weeks, the immobilizer can be discontinued and patients can wean off crutches once able to ambulate without a limp.
Discussion Medial patellar instability, though occurring much less frequently than its lateral counterpart, can be a painful and disabling condition. After the first description of this condition by Hughston and Deese6 in 1988, Nonweiler and DeLee8 reported their experience in 5 patients with medial subluxation after lateral release. Subsequent conservative treatment measures failed in these patients, and they required operative intervention.
Table 1. Tips and Pitfalls to Consider During Lateral Patellotibial Ligament Reconstruction Tips Perform open incision before arthroscopy to prevent distortion of normal anatomy. Measure length of patellar tendon graft, and make sure IT band graft is of same length or greater. Dissect posteriorly along IT band during initial dissection because anterior aspect is often distorted and retracted from previous release. Make sure patellar tendon is not pulled too far distally to create iatrogenic patella baja when tightening grafts. Pitfalls Holding patella centrally while tying grafts can be challenging. Surgeon must avoid overtightening, which can result in lateral subluxation, patella baja, or over-constraining of patellofemoral joint. IT, iliotibial.
e550
G. A. SAWYER ET AL.
After identification of the aforementioned condition, Hughston et al.9 developed multiple surgical techniques to correct it. They described 63 patients (65 knees) who underwent surgical correction of medial subluxation from 1984-1990. Fifty-eight knees (89%) had undergone previous lateral retinacular release. A direct repair technique was used in 39 knees (60%), whereas the remainder underwent lateral patellotibial reconstruction using either a slip of patellar tendon or iliotibial band or a combination of these 2 donor sites. The authors reported that 68% of patients had improvement in functional outcome scores and 75% had subjective improvement at 54 months’ follow-up. They also noted a significant procedural learning curve, with improved subjective patient outcomes in the second half of the study block. Teitge and Torga Spak10 described a technique used in 60 patients for lateral patellofemoral ligament reconstruction using a quadriceps tendon autograft with reported excellent results. In 2007 Shannon and Keene11 described arthroscopic medial retinacular release for treatment of medial patellar instability in 7 patients (9 knees). They reported no further instability and reported excellent results in 6 knees and good results in 3 knees based on the Merchant and Mercer12 criteria. We have attempted several different techniques; the surgical intervention for medial patellar instability preferred by Hughston et al.9 is similar to our described technique using a slip of both patellar tendon and iliotibial band to reconstruct the lateral patellotibial ligament. This technique provides a dynamic restraint to medial patellar subluxation. Similar to medial patellofemoral ligament reconstruction, gauging tension of the reconstruction can be challenging. The surgeon must avoid overtightening, which could result in lateral patellar instability and patella baja. Other potential risks associated with this procedure include patellar tendon rupture due to graft harvest and recurrent medial instability if the graft does not heal. This technique is contraindicated in patients who have undergone a previous surgical intervention involving the patellar tendon, including boneepatellar tendonebone autograft for anterior cruciate ligament reconstruction, tibial tubercle osteotomy, and patellar tendon repair.
The described surgical technique has provided an effective solution for patients with iatrogenic medial patellar subluxation after lateral release. We have not encountered any significant postoperative complications and have anecdotally noted improvements in patient satisfaction and functional outcomes. We are currently compiling 2-year patient outcomes to further evaluate the success of this procedure.
Acknowledgment The authors acknowledge Barry Eckhaus for his outstanding production of the surgical technique video.
References 1. Fithian DC, Paxton EW, Stone ML, et al. Epidemiology and natural history of acute patellar dislocation. Am J Sports Med 2004;32:1114-1121. 2. Hawkins RJ, Bell RH, Anisette G. Acute patellar dislocations. Am J Sports Med 1986;14:117-120. 3. Cofield FH, Bryan RS. Acute dislocation of the patella: Results of conservative treatment. J Trauma 1977;17:526-531. 4. Fithian DC, Pacton EW, Cohen AB. Indication in the treatment of patellar instability. J Knee Surg 2004;17:47-56. 5. Fu FH, Maday MG. Arthroscopic lateral release and the lateral patellar compression syndrome. Orthop Clin North Am 1992;23:601-612. 6. Hughston J, Deese M. Medial subluxation of the patella as a complication of lateral retinacular release. Am J Sports Med 1988;16:383-388. 7. Shellock FG, Jerrold MH, Deutsch AL, Fox JM. Patellar tracking abnormalities: Clinical experience with kinematic MR imaging in 130 patients. Radiology 1989;172:799-804. 8. Nonweiler DE, DeLee JC. The diagnosis and treatment of medial subluxation of the patella after lateral retinacular release. Am J Sports Med 1994;22:680-686. 9. Hughston JC, Flandry F, Brinker MR, Terry GC, Mills JC. Surgical correction of medial subluxation of the patella. Am J Sports Med 1996;24:486-491. 10. Teitge RA, Torga Spak R. Lateral patellofemoral ligament reconstruction. Arthroscopy 2004;20:998-1002. 11. Shannon BD, Keene JS. Results of arthroscopic medial retinacular release for treatment of medial subluxation of the patella. Am J Sports Med 2007;35:1180-1187. 12. Merchant AC, Mercer RL. Lateral release of the patella. Clin Orthop Relat Res 1974;103:40-45.
