SYMPOSIUM ON ACL RECONSTRUCTION/WHAT WE NOW KNOW ABOUT PCL INJURIES
From Evaluation & Treatment of the Injured Athlete: Sports Medicine Update, Boston University School of Medicine
| ACL: MEDIAL PORTAL FEMORAL TUNNEL TECHNIQUE —Christopher D. Harner, MD, Professor, Department of Orthopaedic Surgery, University of Pittsburgh School of Medicine |
| Current technique: speaker performs ≈640 cases per year (all knees), 130 to 150 anterior cruciate ligament (ACL); arthroscopy with medial portal for femoral tunnel; graft fixation—for hamstring, AO washer and screw; for patellar tendon autograft and allograft, interference screw |
| ACL in orthopaedic practice: fourth most common procedure; 85% of surgeons report <10 cases per year; consequently—individual orthopaedists need to select single graft and develop good surgical skills; orthopaedists need more accurate techniques for correct tunnel placement; most common cause of failure—surgical technique, most often tunnel malposition |
| ACL insertion site (femoral): on wall of intercondylar notch, not on roof; transtibial approach—tends to place insertion on roof, at 12 o’clock position; anatomic insertion site—at 2 to 3 o’clock; basic science—indicates proper insertion improves rotational control; study of 14 experienced surgeons found femoral placement highly variable (most around 11 o’clock and 12 o’clock) |
| Principles of tunnel placement: natural insertion sites at location of tunnels; femoral and tibial tunnels should be independent of each other; tunnel placement should not depend on fixation devices; goal—placement at anatomic location |
| Medial portal technique: modified notchplasty for visibility (impeded by instruments); identify femoral insertion; tibial tunnel—place K-wire; intraoperative mini C-arm confirms accurate tunnel placement (knee in full extension; radiographic evaluation of K-wire in relation to Blumenstaat’s line [with hamstring graft, ≈2 mm behind; with patellar tendon graft, directly on line]); drill and dilate; femoral tunnel—flex knee to 120° (arthroscopic leg holder presents problem); place K-wire through medial portal; drill and dilate; intraoperative study—assessed tunnel placement in 50 consecutive ACL reconstructions; found correlation of arthroscopic and radiographic criteria in 100% of cases on femoral side |
| ACL insertion site (tibial): identify anatomic landmarks; between medial and lateral spines (“like goal posts”); free edge of anterior horn of lateral meniscus; using posterior cruciate ligament (PCL) as landmark tends to push ACL insertion too far posteriorly (can lead to failure, requiring 2-stage revision); footprint—posterior half vs central position (“I like to be right in the central position”); radiographic evaluation—confirm placement using mini C-arm; ideal position directly posterior to Blumenstaat’s line (20%-40% posteriorly, on tibial plateau); K-wire placement— parallel pin guide available to adjust K-wire position; intraoperative study showed speaker changed K-wire (3-5 mm) 42% of time (usually too far posteriorly) |
 | Challenge: to rethink tibial tunnel (arthroscopic landmarks may be inaccurate); to consider using intraoperative radiography before drilling tunnel |
| Summary: current technique (medial portal) allows more anatomic placement of femoral tunnel; intraoperative fluoroscopy improves accuracy of tibial tunnel placement; double-bundle reconstruction now being performed (will it improve results? is it reproducible for everyone? technically demanding; 84% of surgeons perform <10 per year); regardless of technique, anatomy (insertion site) should determine tunnel placement |
| ACL: B-T-B WITH CYLINDRICAL BONE PLUGS —Mark J. Lemos, MD, Associate Professor of Orthopaedic Surgery, Boston University School of Medicine, and Director of Sports Medicine, Lahey Clinic, Burlington, Massachusetts |
| Introduction: adopt consistent approach; become proficient in using graft of choice, fixation technique, and rehabilitation program; speaker uses bone-tendon-bone (B-T-B) in ≈50% of cases (avoids use in older patients) |
| B-T-B in orthopaedics: used by 94% of American Orthopaedic Society for Sports Medicine (AOSSM) members; often used by team physicians in college Division 1 and National Football League; larger trends—previous trend away from B-T-B because of complications and from hamstring grafts because of poor fixations, although problems partially resolved; tunnel placement key issue; meta-analysis—compared to hamstring, B-T-B ≈20% more likely to return patients to pre-injury levels and had more static stability; results good with both grafts |
| Advantages of B-T-B: strong graft; readily accessible; rigid fixation; allows accelerated rehabilitation; most commonly used graft; reproducible results; contraindications—skeletal immaturity; patellofemoral instability; possibly older patients |
| Key issues: graft fixation—speaker favors interference screw; some favor bioabsorbable fixation (thought to lessen pain); divergence—found to be 10° to 30° in speaker’s investigation (≤15° acceptable on femoral side); bone-plug geometry—circular plug stronger than trapezoidal plug; risk of fracture ≈50% greater with trapezoidal; procedure for circular plug easier with single surgeon; technique—speaker uses round oscillating saw; learning curve not easy; involves starting at ≈90° and lowering hand relatively quickly; fixation—graft fills tunnel; best fixation possible for ACL surgery; lift-off test reassuring; make tunnel 1 mm larger than plug harvested |
| ACL: THE ROLE OF QUADRICEPS TENDON —John P. Fulkerson, MD, Clinical Professor of Orthopaedic Surgery, University of Connecticut School of Medicine, and Head Team Physician, AHL Hartford Wolfpack, Hartford, Connecticut |
| Advantages of graft: (central quadriceps free tendon [CQFT]); easy access; low morbidity harvest; less pain and quicker rehabilitation; preserves hamstrings (no loss of power in flexion); no added risk of patellar fracture; strong graft; possible simultaneous harvest (with second surgeon); outcome similar to other autografts |
| Benefits of maintaining hamstring: hamstring deficit may be reason women susceptible to ACL tear; hamstring stabilization of pelvis helps maintain patellofemoral mechanics; hamstring necessary for normal knee kinematics; failure rate of hamstring ACL reconstruction higher in women; probable muscle shortening after hamstring regeneration |
| Quadriceps tendon strength: thicker than patellar tendon, with comparable strength; partial thickness harvest preferable; no ruptures in 10 yr using CQFT; quadriceps tendon part of extensor mechanism |
| Surgical procedure: harvest of CQFT safe (easily accessible); incision can be minimized for cosmesis (≥1.5. cm); no risk of neurovascular damage; possible to harvest bone block; cut 7-mm graft (partial thickness of ≈9-mm tendon); whipstitch end of graft (speaker employs uterine T-clamp); place 2.0 to 2.5 cm in each tunnel; apply #5- strength nonabsorbable suture; endobutton on femoral side; biointerference screw on tibial side (reinforced with button); drill hole just large enough to accommodate graft; results—≥2-yr follow-up of initial trial group found no patellofemoral morbidity and no contracture |
| Postoperative pain medication: required for 5 days with CQFT, compared to 19 days with hamstring, 20 with B- T-B; all rehabilitation landmarks reached earlier with CQFT |
| Conclusions: CQFT works well; results consistent; morbidity low; fixation excellent; recovery rapid; knees stable at 1- and 2-yr follow-up; best alternative in speaker’s hands |
| ACL: RETROSCREW SINGLE AND DOUBLE BUNDLE RECONSTRUCTION —Craig D. Morgan, MD, Clinical Professor of Orthopaedics, University of Pennsylvania School of Medicine, and President, The Morgan Kalman Clinic, Wilmington, Delaware |
| RetroScrew reconstruction: provides anatomic fixation, with head of screw at level of intra-articular orifice, where native ACL fixed; on tibial side, RetroScrew delivered over fiberwire suture from medial portal through shoehorn canula onto cannulated RetroScrewdriver positioned anterior to graft in tibial tunnel; screw positioned on RetroScrewdriver, turned counterclockwise until screw head flush with intercondylar floor; benefits—orifice fixation; more stable reconstruction (tibial bone density greatest at level of intercondylar floor); avoids tunnel expansion; avoids early micromotion in distal fixation |
| Background: anatomic fixation—in 1995, speaker presented study of anatomic vs nonanatomic fixation through full range of motion, demonstrating ≈5-mm difference between fixation points (from 140° of flexion to full extension); all-inside ACL reconstruction—speaker developed procedure using quadriceps tendon and midpatellar medial portal with tibial and femoral sockets; performed 400 cases; results—stable grafts; anatomic fixation; independent analysis of prospective study with 100 cases found anatomic fixation, with bell-shaped curve between 1 and 3 mm; no tunnel expansion (recently ascribed to early motion); lesson—anatomic fixation produces stable grafts |
| Surgical procedure: using RetroScrew; single-bundle reconstruction—≥2-yr follow-up of first 92 cases found neither fixation failure, graft failure, subjective instability, nor tunnel expansion on x-ray; double-bundle recon- struction—single femoral socket; screw placed concentrically between 2 bundles (spread 21 mm, about size of native ACL footprint); analysis shows reciprocal tensioning and extension (tension greater on posterolateral bundle in extension, on anteromedial bundle in flexion, and equal in midrange); footprint almost equal to native ACL; by contrast, footprint of single-bundle reconstruction essentially limited to posterolateral bundle |
| A SCIENTIFIC APPROACH TO PCL ANATOMY, BIOMECHANICS, AND TREATMENT —Dr. Harner |
| What we agree on: PCL not same as ACL; PCL more likely to heal than ACL; posterolateral corner critical in decision making; acute, subacute, and chronic injuries treated differently; anterolateral most important component biomechanically and clinically (focus of reconstruction); nonoperative management of isolated PCL injuries remains treatment of choice for grade 1 and 2 injuries; slow postoperative rehabilitation required during early healing phase |
| What we do not agree on: classification system; outcome assessments; surgical management; must agree on principles of classification and how to determine success and failure; room for differences on surgery as long as principles not violated (ie, criteria for anatomy, graft fixation, tensioning, secondary restraints) |
| Anatomy and biomechanics: insertion of anterolateral component on femoral side; insertion of posteromedial component on tibial side; anterolateral component—larger and stronger; cross-section of insertion 3 times midsubstance of ligament; at midpoint, fibers spiral, then fan out as they come through insertion; reproducing this pattern represents challenge to orthopaedists; reciprocal tensioning—anterolateral taut in flexion, relatively lax in extension; posteromedial taut in extension, relatively lax in flexion; insertions of meniscofemoral ligament (MFL) distinctly visible; all components easily seen arthroscopically, providing target areas for insertion (makes double- bundle technique attractive); coupled motions—posterior translation and external rotation; PCL and posterolateral corner interact (PCL primary restraint; posterolateral corner secondary restraint; posterolateral corner injury often missed on varus stress test when lateral collateral ligament (LCL) intact (leads to misdiagnosis of isolated PCL injury; LCL mistakenly thought to contribute to posterolateral corner stability) |
| Classification system: for directing operative and nonoperative management; based on anatomy and pathomechanics; will lead to common approach to timing, reconstruction, and repair; continues to be work in progress; gradations of PCL injuries include—isolated PCL; PCL-posterolateral corner without LCL; PCL-medial cruciate ligament (MCL); in grade 3 injuries, MCL healing unlikely |
| Speaker’s current approach: preserve PCL tissue and augment; based on lessons from previous experience—in early-to-mid 90s, speaker removed entire PCL (along with related sutures, eg, MFL) during single-bundle reconstruction (this approach likely to miss posterolateral corner injury and “doomed for failure”); subsequently, recognizing role of posterolateral corner improved results significantly; posteromedial and meniscofemoral components often intact and should not be removed; current surgical setup—sandbag for knee flexion; post (“silent resident”) to hold knee in position; single-bundle reconstruction—performed since 1990; used in acute combined injuries <3 wk old; good results in acute injuries; single-bundle augmentation performed in ≈33% of cases; double-bundle reconstruction—used in chronic injuries; chronic cases with severe laxity; PCL-posterior lateral corner injuries; dislocated knees |
Educational Objectives
| The goal of this program is to educate orthopaedists about anterior cruciate ligament (ACL) reconstruction and a scientific approach to the posterior cruciate ligament (PCL). After hearing and assimilating this program, the surgeon will be better able to: |
| 1. Perform ACL reconstruction using the medial portal and femoral tunnel technique. |
| 2. Describe ACL reconstruction with bone-patellar tendon-bone graft and cylindrical bone plugs. |
| 3. Identify the role of quadriceps tendon graft in ACL reconstruction. |
| 4. Explain the use of the RetroScrew in single- and double-bundle ACL reconstruction. |
| 5. Adopt a scientific approach to posterior cruciate ligament (PCL) anatomy, biomechanics, and injury treatment. |
Discussed on This Program
Fontbote CA et al: Neuromuscular and biomechanical adaptation.of patients with isolated deficiency of the posterior cruciate ligament. Am J Sports Med 33:982, 2005; Forster MC et al: Patellar tendon or four-strand hamstring? A systematic review of autografts for anterior cruciate ligament reconstruction. Knee 12:225, 2005; Harner CD et al: Quantitative analysis of human cruciate ligament insertions. Arthroscopy 15:741, 1999; Harvey A et al: Fixation of the graft in reconstruction of the anterior cruciate ligament. J Bone Joint Surg Br 87:593, 2005; Hashemi J et al: The mechanical properties of the human patellar tendon are correlated to its mass density and are independent of sex. Clin Biomech (Bristol, Avon) 20:645, 2005; Hiemstra LA et al: Hip strength following hamstring tendon anterior cruciate ligament reconstruction. Clin J Sport Med 15:180, 2005; Lemos MJ et al: Assessment of initial fixation of endoscopic interference femoral screws with divergent and parallel placement. Arthroscopy 11:37, 1995; Loh JC et al: Knee stability and graft function following anterior cruciate ligament reconstruction: Comparison between 11 o'clock and 10 o'clock femoral tunnel placement. Arthroscopy 19:297, 2003; Ma CB et al: Hamstring anterior cruciate ligament reconstruction: a comparison of bioabsorbable interference screw and endobutton-post fixation. Arthroscopy 20:122, 2004; Milankov M et al: Anatomic reconstruction of the anteromedial and posterolateral bundles of the anterior cruciate ligament using hamstring tendon grafts. Arthroscopy 21:639; Miller MD et al: Posterior cruciate ligament: current concepts. Instr Course Lect51:347, 2002; Morgan CD et al: Anatomic tibial graft fixation using a retrograde bio-interference screw for endoscopic anterior cruciate ligament reconstruction. Arthroscopy 18:E38, 2002; Morgan CD et al: Histologic findings with a bioabsorbable anterior cruciate ligament interference screw explant after 2.5 years in vivo. Arthroscopy 18:E47, 2002; Nebelung W et al: Thirty-five years of follow-up of anterior cruciate ligament-deficient knees in high-level athletes. Arthroscopy 21:696, 2005; Peccin MS et al: Interventions for treating posterior cruciate ligament injuries of the knee in adults. Cochrane Database Syst Rev:CD002939, 2005; Radford MJ et al: The natural history of a bioabsorbable interference screw used for anterior cruciate ligament reconstruction with a 4-strand hamstring technique. Arthroscopy 21:707, 2005; Sekiya JK et al: Biomechanical analysis of a combined double-bundle posterior cruciate ligament and posterolateral corner reconstruction. Am J Sports Med 33:360, 2005; Theut PC et al: Anterior cruciate ligament reconstruction utilizing central quadriceps free tendon. Orthop Clin North Am 34:31, 2003; West RV et al: Graft selection in anterior cruciate ligament reconstruction. J Am Acad Orthop Surg 13:197, 2005; Yoldas EA et al: Arthroscopically assisted meniscal allograft transplantation with and without combined anterior cruciate ligament reconstruction. Knee Surg Sports Traumatol Arthrosc 11:173, 2003.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial relationship with the manufacturer or provider of any commercial product or service discussed. The following has been disclosed: Dr. Fulkerson—dj Orthopedics (royalties [Trupull brace]); Dr. Morgan—Arthrex, Inc, Naples, Florida (stockholder; consultant)
Drs. Harner, Lemos, Fulkerson, and Morgan were recorded at Evaluation & Treatment of the Injured Athlete: Sports Medicine Update, sponsored by the Boston University School of Medicine, July 19-23, 2004, in Martha’s Vineyard, Massachusetts. The Audio-Digest Foundation thanks the speakers and the sponsor for their cooperation in the production of this program.
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