Ch18.qxd 10/05/05 4:59 PM Page 295 18 Lysis of Pretibial Patellar Tendon Adhesions (Anterior Interval Release) to Treat Anterior Knee Pain after ACL Reconstruction Sumant G. Krishnan, J. Richard Steadman, Peter J. Millett, Kimberly Hydeman, and Matthew Close Abstract comes in the treatment of recalcitrant anterior We report the clinical results of an anterior knee pain after ACL reconstruction. interval release for recalcitrant anterior knee pain associated with decreased patellar mobility Introduction after anterior cruciate ligament (ACL) recon- Arthroscopic anterior cruciate ligament (ACL) struction. reconstruction has become one of the most Thirty consecutive patients with recalcitrant commonly performed procedures in orthopedic anterior knee pain and decreased patellar mobil- surgery and knee reconstruction.13,14,21 Over the ity after ACL reconstruction underwent an last decade, the results of arthroscopic ACL arthroscopic lysis of adhesions and scar of the dis- reconstruction have remained outstanding in tal patella tendon from the proximal anterior tibia most peer-reviewed series, regardless of surgical (anterior interval release). Anterior knee pain was technique.13,21 However, the published literature initially treated nonoperatively. Failure of nonop- regarding postoperative complications after erative treatment was defined by recalcitrant ACL reconstruction remains quite sparse.5,6,10,38 anterior knee pain and no improvement in func- Anterior knee pain is a well-documented com- tional outcome, assessed by Lysholm scores and plication after arthroscopic ACL reconstruction patient questionnaires. Minimum clinical follow- and has been reported as the most common com- up was 2 years. All anterior interval release proce- plaint after ACL surgery.1,6,10,19,30,31,34,38 While the dures were also performed by the senior author initial studies reported anterior knee pain after using a high inferolateral viewing portal in order patellar tendon autograft reconstruction, recent to arthroscopically evaluate the anterior interval work confirms a real incidence of anterior knee between the patella tendon and tibia. Prior to pain even after hamstring or allograft ACL recon- anterior interval release, Lysholm score aver- struction.1,32 Consequently, the etiology of this aged 68 (range 18–90). Postoperative Lysholm anterior knee pain remains elusive and contro- score averaged 85 (range 68–100) (P < 0.0001). versial.6,12,24,27,32 Postoperative range-of-motion did not change Paulos et al.26,27 were the first to describe the significantly. Postoperative instability examina- “infrapatellar contracture syndrome (IPCS),” an tions were all graded zero using the International “exaggerated pathologic fibrous hyperplasia” of Knee Documentation Committee (IKDC) system. soft tissue in the anterior knee after intra-articu- Average patient satisfaction at follow-up was 8.0 lar surgery and specifically after ACL reconstruc- (1 = very dissatisfied; 10 = very satisfied). tion. IPCS can create significant arthrofibrosis, Early operative intervention with an anterior loss of knee motion, decreased patellar mobility interval release has been shown in this series to (“patellar entrapment”), and even patella infera. result in significantly improved functional out- The diagnosis of IPCS according to these authors 295 Ch18.qxd 10/05/05 4:59 PM Page 296 296 Etiopathogenic Bases and Therapeutic Implications was based on a “decrease in patellar mobility as 90°, and no warmth of the knee relative to the compared with the opposite knee,” zero or nega- contralateral side.7,33 Intraoperatively, no tive passive patellar tilt, and less than 2 cm of patient demonstrated other ligament pathology superior/inferior patellar glide. Without appro- in addition to the ACL injury. Seventeen priate identification and aggressive treatment, patients underwent concurrent meniscus IPCS after ACL reconstruction results in signifi- trephination, and no patients underwent a cant functional morbidity. meniscus repair. Postoperative rehabilitation Several others have also documented the inci- followed the same protocol: full passive and dence of adhesions of the patellar tendon to the active range-of-motion exercises (with emphasis anterior tibia after arthroscopic proce- on terminal extension), crutches in the immedi- dures.2,4,8,15,16,20,22,26-29,33,36,37 Ahmad et al.2 ate postoperative period with progressive full demonstrated the biomechanical effect of such weightbearing, and a hinged knee brace for the patellar tendon adhesions to the anterior tibia. first 6 postoperative weeks. Strengthening exer- These authors documented an effective patella cises did not begin until full range-of-motion infera when the patellar tendon was adhesed to was achieved. the anterior tibial cortex in this pretibial recess. All 30 patients complained of disabling ante- The adhesions were shown to significantly alter rior knee pain within 6 weeks of the ACL recon- both patellar and tibial kinematics and contact – struction. All Lachman examinations were potentially increasing patellofemoral and graded zero using the International Knee tibiofemoral contact forces that may eventually Documentation Committee system (IKDC). result in arthrosis.2,8,15,35,41 Physical examination demonstrated signifi- We have encountered a population of patients cantly restricted passive patellar and patellar with recalcitrant anterior knee pain after ACL tendon mobility relative to the contralateral reconstruction that have failed conservative side, both in medial/lateral and in superior/infe- treatment and have subtle alterations in patellar rior excursion. All patients demonstrated less mobility despite a full range of flexion and than 2 cm of superior/inferior passive patellar extension. To our knowledge, this clinical entity excursion, decreased medial/lateral passive and its appropriate treatment have not yet been patellar excursion relative to the contralateral described. We report here the clinical results of side, and an inability to passively “tilt” the infe- an arthroscopic release of pathologic adhesions rior pole of the patella away from the anterior in the pretibial recess (anterior interval release) tibial cortex (Figure 18.1).20,28 Range-of-motion in these patients to treat the anterior knee pain. in all 30 patients averaged 0° of extension (range 5° of hyperextension to a 3° lack to full exten- Materials and Methods sion) and 140° of flexion (range 130°–155°). No Between 1992 and 1998, 30 consecutive patients patients demonstrated either a 10° or greater with recalcitrant anterior knee pain after isolated loss of knee extension or a 25° or greater loss of ACL reconstruction underwent an arthroscopic knee flexion.20,28 anterior interval release by the senior author. All Initial treatment consisted of nonsteroidal 30 patients had previously undergone arthro- anti-inflammatory (NSAID) medication, patellar scopic ACL reconstruction by the senior author, mobilization exercises, and closed-chain quadri- using a 2-incision technique and an ipsilateral ceps-strengthening exercises for a minimum of bone-patellar tendon-bone autograft with inter- 12 weeks in all 30 patients. Failure of conservative ference screw fixation. Mean age at the time of treatment was identified by recalcitrant anterior ACL reconstruction was 32 years (range 16–43 knee pain and no further improvement in func- years). There were 14 men and 16 women tional outcome as assessed by a standardized patients. For all 30 patients, the ACL reconstruc- patient questionnaire and the scoring system of tion was the first surgery performed on that Lysholm and Gillquist.39 knee. Mean duration between injury and ACL The anterior interval release was performed reconstruction was 6 weeks (range 2–16 weeks). at a mean duration of 9 months after the ACL No patient demonstrated abnormal posterior, reconstruction (range 6–12 months). Postope- posterolateral, varus, or valgus examinations. rative rehabilitation consisted of immediate pas- Criteria required before proceeding with ACL sive patellar mobilization exercises, immediate reconstruction included ability to perform a progressive weightbearing with crutches, and no supine straight-leg raise, flexion greater than brace. Ch18.qxd 10/05/05 4:59 PM Page 297 Lysis of Pretibial Patellar Tendon Adhesions (Anterior Interval Release) to Treat Anterior Knee Pain after ACL Reconstruction 297 Figure 18.1. Normal passive “tilt” of the inferior pole of the patella away from the anterior tibial cortex. Minimum clinical follow-up after the ante- tionnaire. The questionnaire documents pain, rior interval release was 2 years. All patients stiffness, function during daily and sporting were objectively examined by the senior author, activities, and satisfaction based on a 10-point functionally evaluated using the scoring system scale (1 point = very dissatisfied; 10 points = of Lysholm and Gillquist,39 and subjectively very satisfied). Statistical significance for data evaluated using a standardized patient ques- analysis was set at P < 0.05. Ch18.qxd 10/05/05 4:59 PM Page 298 298 Etiopathogenic Bases and Therapeutic Implications Surgical Technique for Arthroscopic (at the level of the meniscus) to approximately 1 cm distal along the anterior tibial cortex Anterior Interval Release (Figure 18.4B). Great care was taken to avoid Arthroscopy was performed with the arthroscope cauterizing or burning the bone of the anterior in an inferolateral portal relative to the patella tibia or the patellar tendon. Meticulous hemo- and the