ACL autograft reconstruction revisions with tendon allografts: Possibilities and outcomes. A one-year follow-up of 39 patients.

BACKGROUND: The number of anterior cruciate ligament (ACL) reconstructions is steadily rising in France. Re-tear rates of up to 25% have been reported and graft selection remains a notable challenge. Allografts, although rarely used in France, can be a viable option. The primary objective of this study was to demonstrate the benefits of ACL revision with allografts, by determining subjective scores (IKDC score and KOOS), measuring laxity, and evaluating the rate of return to sports. HYPOTHESIS: Tendon allografts are reliable and can be used in France for ACL reconstruction revision. MATERIAL AND METHODS: We conducted a retrospective study including 39 patients managed in two centres between 2004 and 2016 and followed up for at least a year. Patients were eligible if they had undergone tendon allograft reconstruction for ACL revision with or without rupture of a peripheral plane. We excluded underage patients and patients with a history of ligament injury in the contralateral knee. Mean age was 32 years. The allografts were extensor mechanisms, anterior or posterior tibial tendons, fascia lata tendons, hamstring tendons, and a short fibular tendon. They were obtained from French and Belgian tissue banks. They were used for the reconstruction of 39 ACLs and 11 collateral ligaments. The IKDC score and KOOS were determined in all patients. Laximetry was performed in 31 patients by an independent examiner. RESULTS: Mean follow-up was 3.5 years. Arthroscopic release was required in one patient, and 2 patients experienced re-tears. No deep surgical site infections were recorded. The subjective IKDC score and the KOOS improved significantly, from 53.6 to 80.7 and from 60.4 to 83.2, respectively. Mean postoperative differential laxity was 1.4mm (KT 1000) and 1.6mm (GNRB®). Of the 3 patients who were professional athletes, 2 had returned to sports at the same level one year later, and among the recreational athletes, 54% had resumed their previous sporting activities. CONCLUSION: In the setting of complex ligament reconstruction revision, tendon allografts are reliable and can be used in France. LEVEL OF EVIDENCE: IV; retrospective cohort study.

Complications After Anterior Cruciate Ligament Reconstruction and Their Relation to the Type of Graft: A Prospective Study of 958 Cases.

BACKGROUND: Complications and adverse events after anterior cruciate ligament (ACL) reconstruction are well known, but they have been underestimated in previous studies. PURPOSE: To describe the complications and adverse events after ACL reconstruction within a 2-year follow-up and analyze them in relation to the type of graft. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: From 2000 to 2012, 958 patients with an isolated ACL injury underwent surgery by a single knee surgeon. ACL reconstruction was performed with the medial portal technique for the femoral tunnel and the use of bone-patellar tendon-bone (BPTB) or hamstring tendon graft. Patients were reviewed at 6 weeks and 3, 6, 12, and 24 months after surgery with the International Knee Documentation Committee score, plain radiographs, and the KT-1000 arthrometer. RESULTS: Of 958 patients enrolled, 147 (15%) were lost at last follow-up. The 2 groups (bone-patellar tendon-bone [n = 257] and hamstring [n = 554]) were similar regarding the mean age at the time of surgery and preoperative anterior laxity. The main complications were as follows: anterior knee pain (n = 130 of 811, 16%), stiffness (n = 72, 8.8%), secondary meniscal lesions (n = 59, 7.2%), pain attributed to fixation (n = 79, 9.7%), ACL rerupture (n = 47, 5.7%), contralateral ACL ruptures (n = 24, 3%), patellar fractures (n = 3, 0.3%), infections (n = 9, 1%), and thromboembolic complications (n = 5, 0.6%). There was no significant difference between the grafts with respect to the frequency of joint stiffness, secondary meniscal lesions, or anterior knee pain. During the first 2 postoperative years, the percentage of patients with anterior knee pain was higher in the patellar tendon group (23.3% vs 12.6%, P < .001); however, this difference was not significant after the 2-year interval (3.1% vs 2.5%, P = .63). The percentage of patients with a rerupture of the graft was significantly lower in the patellar tendon group than in the hamstring group (25 of 811 [3.1%] vs 57 of 811 [7%], P = .023). Similar results were recorded regarding the pain related to the hardware material (7 of 811 [0.8%] in the BPTB group vs 113 of 811 [13.9%] in the hamstring group, P = .001). The percentage of ACL ruptures contralateral to the repair was higher in the patellar tendon group (41 of 811 [5%] vs 17 of 811 [2%], P = .016). CONCLUSION: The total rate of complications after an ACL reconstruction was 39%, and the surgical revision rate for any reason was 28%. Problems with the hardware material were more frequent in the hamstring group, leading to an increased rate of surgical revision. Anterior knee pain was initially higher in the patellar tendon group, but there was no significant difference in a 2-year interval. The rerupture rate was statistically higher in the hamstring group.

Recurrent posterior knee laxity: diagnosis, technical aspects and treatment algorithm.

PURPOSE: Aim of this study was to determine the characteristics, clinical and radiological diagnostic methods of PCL isolated and combined knee injuries. METHODS: One hundred and twelve patients with a recurrent posterior knee laxity were surgically treated. Clinical examination, MRI, Telos™ stress dynamic X-rays, KT-1000 measurements and the IKDC questionnaire were used to diagnose and evaluate these injuries. RESULTS: Median follow-up was 4.5 years (2-11 years). Thirty-two patients (28.6 %) had an isolated posterior laxity, 53 (47.3 %) a posterior posterolateral laxity, 21 (18.7 %) a posterior posteromedial laxity and six (5.4 %) patients had a complex posterior and mediolateral laxity. Road traffic accidents and sports injuries were the main causes of trauma. The mean preoperative value of posterior tibial translation was 13.5 mm (SD 1.4) and the mean postoperative value was 4.4 mm (SD 1.7) as measured with the Telos device. In the cases with a concomitant ACL rupture, the mean preoperative value of anterior tibial translation was 6.5 mm (SD 1.3) and the mean postoperative value was 1.7 mm (SD 0.8). The mean pre- and postoperative IKDC scores were 74.5 (SD 4.2) and 87.9 (SD 3.1), respectively. Meniscal and/or cartilage injuries were found in 80 patients (71.4 %). CONCLUSIONS: Recurrent posterior knee laxity can be restored with the one-stage PCL reconstruction using a quadriceps graft and reconstruction of the posteromedial-posterolateral lesions using the LaPrade techniques. The benefits of this study include enabling surgeons to accurately manage these injuries from a clinical perspective, and treating them with a specific surgical algorithm. LEVEL OF EVIDENCE: III.

Clinical and radiographic results of arthroscopic partial lateral meniscectomies in stable knees with a minimum follow up of 20 years.

PURPOSE: The purpose of this retrospective multicentric study was to evaluate the long-term effects of lateral meniscectomy and to identify those patients who are at the most risk of developing osteoarthritis (OA). METHODS: Eighty-nine arthroscopic partial lateral meniscectomies in stable knees with a mean follow-up of 22 ± 3 years were included. The following influencing factors were analyzed: age, sex, body mass index (BMI), physical activity, alignment, the types of meniscal lesions, the extent of meniscal resections and the initially associated cartilage lesions. An independent examiner reviewed all patients, using subjective (KOOS and IKDC scores) and objective clinical and radiological evaluations (IKDC score). The contralateral knee was used as a reference to calculate the prevalence and the incidence of OA. RESULTS: The mean age at the time of surgery was 35 ± 13 years. The main location of the lesions was the mid-section of the lateral meniscus (79% of the cases). At the latest follow-up, 48% of the patients had an active lifestyle with as many as 48% of the patients enjoying moderate to intense physical activity 22 years after the procedure (vs. 71% before surgery). The KOOS score evolved from 82 to 69% during the same period. The prevalence of OA was 56% in the affected knee and the difference of prevalence between the operated and healthy knees was 44%. In those patients presenting with an OA of the operated knee and a normal contralateral knee, the incidence of OA was 53%. Predictors of OA were an age superior to 38 years at the time of surgery, obesity (BMI >30), and valgus malalignment as well as the presence of cartilage and degenerative meniscal lesions at the time of surgery. CONCLUSION: In the long term, arthroscopic partial lateral meniscectomy in stable knees without initial cartilage lesions might yield good to excellent results in young patients. Patients are at higher risk to develop symptomatic OA if they are over 40, having a high BMI, valgus malalignment and cartilage lesions at the time of surgery. This study provides precise guidelines for the surgical treatment of lateral meniscus tears. LEVEL OF EVIDENCE: IV.

Histological features of the ACL remnant in partial tears.

BACKGROUND: The aim of this study was to investigate the histological features of the remaining fibers bridging the femur and tibia in partial ACL tears. METHODS: Twenty-six ACL remnants were harvested from patients who had arthroscopic criteria concordant with a partial tear. Histological analysis includes cellularity, blood vessel density evaluation and characterization of the femoral bony insertion morphology. Immunohistochemical studies were carried out to determine cells positive for α-smooth actin and for mechanoreceptor detection. RESULTS: In these samples, a normal femoral insertion of the remnant was present in 22.7% of the cases. In 54% of the samples, substantial areas of hypercellularity were observed. Myofibroblasts were the predominant cell type and numerous cells positive for α-smooth actin were detected at immunostaining. Blood vessel density was increased in hypercellularity areas and in the synovial sheet. Free nerve endings and few Golgi or Ruffini corpuscles were detected in 41% of the specimens. The cellularity was correlated to the time between injury to surgery (p=0.001). CONCLUSION: Competent histological structures including a well-vascularized synovial sheet, numerous fibroblasts and myofibroblasts and mechanoreceptors were found in ACL remnants. These histological findings bring additional knowledge towards the preservation of the ACL remnant in partial tears when ACL reconstruction or augmentation is considered. CLINICAL RELEVANCE: Descriptive laboratory study.

Neurovascular anatomic relationships to arthroscopic posterior and transseptal portals in different knee positions.

BACKGROUND: No study exists that directly measures the distances between posterior portals and the popliteal artery under arthroscopic conditions. PURPOSE: To define the anatomic relationship between the neural structures and standard posterior arthroscopic portals and between the popliteal artery and posterior as well as transseptal portals in different knee positions. STUDY DESIGN: Descriptive laboratory study. METHODS: Seventeen fresh-frozen cadaveric knees were used. The posterolateral, posteromedial, and transseptal portals were established at 90° of knee flexion. The popliteal artery was revealed using a shaver placed through the posteromedial portal. The distance from those portals to the popliteal artery was measured using a precision caliper. After the measurements were made, each specimen was dissected. The distance from a needle, blade, and cannula in each portal site to the adjacent neural structures was successively measured at 30°, 90°, and 120° of knee flexion. RESULTS: The mean distance (in millimeters) from the posterolateral, posteromedial, and transseptal portals to the popliteal artery was significantly smaller at 30° (32.1 ± 4.6, 36.5 ± 4.9, and 9.0 ± 3.9, respectively) than at 90° (40.7 ± 5.1, 41.0 ± 3.8, and 18.0 ± 3.8, respectively) and 120° (38.4 ± 4.8, 38.7 ± 6.0, and 21.0 ± 4.0, respectively) of knee flexion. The mean distance from the posterolateral portal to the common peroneal nerve at 90° of flexion (needle, 26.6 ± 9.5; blade, 24.7 ± 6.9; cannula, 22.1 ± 6.9) was significantly greater than the distance at 30° (needle, 23.4 ± 6.5; blade, 21.4 ± 6.4; cannula, 18.4 ± 6.3) and 120° (needle, 21.8 ± 6.6; blade, 19.1 ± 6.3; cannula, 17.4 ± 6.7) of knee flexion. The mean distance between the posteromedial portal and the inferior infrapatellar branch of the saphenous nerve at 30° (needle, 18.6 ± 4.3; blade, 15.5 ± 3.3; cannula, 13.7 ± 5.8) of flexion was smaller than at 90° (needle, 20.1 ± 6.1; blade, 16.5 ± 5.3; cannula, 14.3 ± 4.4) and 120° (needle, 21.1 ± 3.6; blade, 17.7 ± 4.9; cannula, 15.1 ± 5.9) of flexion, but there was no statistical significance. The mean distance from the posteromedial portal to the sartorial branch of the saphenous nerve at 30° (needle, 22.8 ± 6.1; blade, 19.8 ± 5.3; cannula, 17.7 ± 6.2) of flexion was significantly smaller than that at 90° (needle, 29.7 ± 3.6; blade, 26.3 ± 6.3; cannula, 23.1 ± 4.7) and 120° (needle, 31.5 ± 3.9; blade, 28.9 ± 4.1; cannula, 25.4 ± 5.1) of flexion. Conclusion/ CLINICAL RELEVANCE: The position of 90° of knee flexion is safe to establish posterior and transseptal arthroscopic portals. The position of 120° of knee flexion is practically safe to establish posteromedial and transseptal portals, but it is unsafe to create a posterolateral portal because the risk of damaging the common peroneal nerve is high. The position of 30° of knee flexion is not recommended to establish posterior arthroscopic portals.

Arthroscopic retrograde osteochondral autograft transplantation for cartilage lesions of the tibial plateau: a prospective study.

BACKGROUND: There are only 2 reported cases of arthroscopic retrograde osteochondral autograft transplantations regarding tibial plateau cartilage defects. PURPOSE: To present a detailed description of arthroscopic retrograde osteochondral autograft transplantation of the tibial plateau as well as to provide its advantages and disadvantages in comparison with other techniques. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Four patients (3 men and 1 woman; mean age, 31.2 years) suffering from tibial plateau cartilage lesions underwent surgery. In each case, the lesions were caused by sports injuries. There were 3 lateral and 1 medial tibial plateau defects. The International Knee Documentation Committee (IKDC) score and Knee injury and Osteoarthritis Outcome Score (KOOS) were recorded preoperatively and postoperatively. Radiological assessment was made by plain radiographs, CT arthroscans, and MRI. RESULTS: The mean follow-up was 55 months (range, 52-60). The mean preoperative IKDC score was 53.5 (range, 37-66), while the mean postoperative IKDC score at final follow-up was 95.4 (range, 93.1-97.7). Regarding the KOOS calculation, there was significant improvement concerning each parameter after surgery. All patients were satisfied with the surgical procedure and returned to their previous activity level. Postoperative imaging showed very good adaptation and incorporation of the osteochondral autografts. CONCLUSION: Treatment of tibial plateau cartilage defects with arthroscopic retrograde osteochondral autograft transplantation could be performed on a routine basis in clinical practice. The results were encouraging and showed good incorporation of the graft, a minimal failure rate, and satisfactory functional outcomes of patients.

Successful treatment of painful irreparable partial meniscal defects with a polyurethane scaffold: two-year safety and clinical outcomes.

BACKGROUND: A novel, biodegradable, polyurethane scaffold was designed to fulfill an unmet clinical need in the treatment of patients with painful irreparable partial meniscal defects. HYPOTHESIS: The use of an acellular polyurethane scaffold for new tissue generation in irreparable partial meniscal defects provides both pain relief and improved functionality. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Fifty-two patients with irreparable partial meniscal defects (34 medial and 18 lateral, 88% with 1-3 previous surgeries on the index meniscus) were implanted with a polyurethane scaffold in a prospective, single-arm, multicenter, proof-of-principle study. Safety was assessed by the rate of scaffold-related serious adverse events (SAEs) and the International Cartilage Repair Society articular cartilage scoring system comparing magnetic resonance imaging (MRI) at 24 months to MRI at baseline (1 week). Kaplan-Meier time to treatment failure distributions were performed. Clinical outcomes were measured comparing visual analog scale, International Knee Documentation Committee, Knee Injury and Osteoarthritis Outcome Score (KOOS), and Lysholm scores at 24 months from baseline (entry into study). RESULTS: Clinically and statistically significant improvements (P < .0001) compared with baseline were reported in all clinical outcome scores (baseline/24 months): visual analog scale (45.7/20.3), International Knee Documentation Committee (45.4/70.1), KOOS symptoms (64.6/78.3), KOOS pain (57.5/78.6), KOOS activities of daily living (68.8/84.2), KOOS sports (30.5/59.0), KOOS quality of life (33.9/56.6), and Lysholm (60.1/80.7), demonstrating improvements in both pain and function. The incidence of treatment failure was 9 (17.3%) patients, of which 3 patients (8.8%) had medial meniscal defects and 6 patients (33.3%) had lateral meniscal defects. There were 9 SAEs requiring reoperation. Stable or improved International Cartilage Repair Society cartilage grades were observed in 92.5% of patients between baseline and 24 months. CONCLUSION: At 2 years after implantation, safety and clinical outcome data from this study support the use of the polyurethane scaffold for the treatment of irreparable, painful, partial meniscal defects.

Fixation of posterior cruciate ligament avulsion fracture with the use of a suspensory fixation.

PURPOSE: Posterior cruciate ligament (PCL) avulsion fractures are uncommon injuries, and their treatment, still, remains difficult. There are procedures described in the literature which are minimal invasive and use either sutures or screws to stabilize the avulsed fragment. The purpose of this study was to present an innovative arthroscopic technique using a suspensory device with specific biomechanical properties. The aim of this study was to determine whether this technique was effective in the treatment of PCL avulsion fractures and applicable in everyday clinical practice. METHODS: Two patients with an isolated posterior cruciate ligament avulsion fracture were operated under arthroscopy. The Endobutton device was used to stabilize the fracture, and a double-spike plate was used to secure the fixation. The clinical assessment of patients was made by plain radiographs, CT scan, MRI and IKDC examination form. RESULTS: The median operative time was 57.5 min (range 55-60). No posterior tibial sag was noticed, and the range of motion was normal. No complications were recorded, and both patients returned to their usual daily activities. Both fractures had healed at 10 months postoperatively. CONCLUSIONS: Treatment outcomes using a suspensory device in the fixation of posterior cruciate ligament avulsion fractures are encouraging. The small size of the device makes it easy to handle, and the procedure is simple and does not require multiple sutures and bony tunnels. This technique offers sufficient compression, restores the length of posterior cruciate ligament and can fix avulsion fragments of any size. LEVEL OF EVIDENCE: Therapeutic study, Case series with no comparison group, Level IV.

Arthroscopic treatment of localized pigmented villonodular synovitis of the knee.

PURPOSE: The purpose of this study was to review the outcome of the arthroscopic treatment of localized pigmented villonodular synovitis of the knee and to determine the recurrence rate with clinical and magnetic resonance imaging evaluation at midterm follow-up. METHODS: Thirty consecutive patients diagnosed with localized pigmented villonodular synovitis of the knee were treated arthroscopically between 1990 and 2008. Clinical assessment was made with the use of Lysholm Knee Scale, and radiologic assessment was done by plain radiographs and magnetic resonance imaging of the knee. Recurrence rate of the disease was also estimated. RESULTS: The average follow-up was 75 months (range 12-144). The median age of the patients was 46 years (range 23-71). Symptoms were discomfort of the knee (100%), swelling (90%), locking (50%), pain (10%) and palpable mass (15%). A history of knee trauma was present in 10% of the patients. The nodules were localized in the gutters (45%), suprapatellar pouch (26%), patellar fat pad (13%), posterior compartment of the knee (13%) and in the femoral notch (9%). The median Lysholm Knee Score was 56.5 (range 53-60) and 85.5 (83-88) preoperatively and at final follow-up, respectively. No postoperative complications occurred. CONCLUSIONS: Arthroscopy is a safe and effective procedure for the treatment of localized pigmented villonodular synovitis of the knee. Magnetic resonance imaging is essential to diagnose this pathologic condition and to define accurately its localization and treatment strategy.

Revision ACL reconstruction: influence of a lateral tenodesis.

PURPOSE: The aims of this article were to report the objective results of revision ACL reconstruction and to assess the influence of an associated lateral extra-articular tenodesis on knee stability and IKDC score. METHODS: This study focused on revision ACL reconstruction and was conducted over a 10-year period, from 1994 to 2003 with ten French orthopedic centers participating. The minimum follow-up required was 2 years. To be included, patients had to be evaluated at follow-up with the objective International Knee Documenting Committee (IKDC) scoring system. In 2006, 163 patients met the inclusion criteria. RESULTS: The objective IKDC knee score improved significantly after revision ACL reconstruction, with 72% IKDC A + B (26% A). When a lateral tenodesis was performed, 80% had a negative pivot shift, versus 63% without (P = 0.03), but there was no significant difference in the IKDC score. CONCLUSION: This study shows a significant improvement in the IKDC score after revision ACL reconstruction. The association of a lateral extra-articular tenodesis with the intra-articular graft increases knee stability after revision ACL reconstruction; however, this additional procedure does not significantly alter the IKDC score at follow-up. LEVEL OF EVIDENCE: Retrospective case series, Level IV.

Causes for failure of ACL reconstruction and influence of meniscectomies after revision.

The purpose of this multicenter retrospective study was to analyze the causes for failure of ACL reconstruction and the influence of meniscectomies after revision. This study was conducted over a 12-year period, from 1994 to 2005 with ten French orthopaedic centers participating. Assessment included the objective International Knee Documenting Committee (IKDC) 2000 scoring system evaluation. Two hundred and ninety-three patients were available for statistics. Untreated laxity, femoral and tibial tunnel malposition, impingement, failure of fixation were assessed, new traumatism and infection were recorded. Meniscus surgery was evaluated before, during or after primary ACL reconstruction, and then during or after revision ACL surgery. The main cause for failure of ACL reconstruction was femoral tunnel malposition in 36% of the cases. Forty-four percent of the patients with an anterior femoral tunnel as a cause for failure of the primary surgery were IKDC A after revision versus 24% if the cause of failure was not the femoral tunnel (P = 0.05). A 70% meniscectomy rate was found in revision ACL reconstruction. Comparison between patients with a total meniscectomy (n = 56) and patients with preserved menisci (n = 65) revealed a better functional result and knee stability in the non-meniscectomized group (P = 0.04). This study shows that the anterior femoral tunnel malposition is the main cause for failure in ACL reconstruction. This reason for failure should be considered as a predictive factor of good result of revision ACL reconstruction. Total meniscectomy jeopardizes functional result and knee stability at follow-up.

Prospective study of refractory greater trochanter pain syndrome. MRI findings of gluteal tendon tears seen at surgery. Clinical and MRI results of tendon repair.

OBJECTIVES: (1) To compare MRI and surgical findings in patients with refractory greater trochanter pain syndrome and (2) to assess surgical outcomes. METHODS: All consecutive patients seen between 2002 and 2006 by a single clinician were selected for surgical treatment according to the following criteria: (1) tendinopathy confirmed by physical tests; (2) painful disability persisting for at least 6 months despite treatment; (3) on MRI: area of high signal intensity on T2-weighted images, in the area of gluteus medius and/or minimus tendon; and (4) absence of marked muscle atrophy or fatty degeneration. Two musculoskeletal radiologists interpreted images by consensus. A single surgeon operated on all patients. RESULTS: Eight patients met the criteria for surgery. All were women, aged 71.1 (SD: 9.4). Mean symptoms duration before surgery: 14.3 months (11.8). Surgery confirmed the presence of a tear of the lateral part of the gluteus medius tendon in all eight patients, with an associated tear of its main tendon in one patient, all tears revealed on MRI. An associated tear of the gluteus minimus tendon was present at surgery in five patients, of which three were not seen on MRI (false negative). Bursitis was confirmed in all eight patients. Steady complete remission of spontaneous and provoked (physical examination) pain was observed in seven patients and partial remission in one (mean follow-up: 22.4 months (SD: 16.3)). Six MRIs performed after 20+/-12 months showed good reinsertion of the sutured tendon. CONCLUSION: The eight MR images of tear of the lateral part of the gluteus medius tendon were all confirmed at surgery. Three of five associated tendon tears (gluteus minimus only) were not seen on MRI. Surgical treatment was very effective in all patients but one.

Using navigation to measure rotation kinematics during ACL reconstruction.

Rotational kinematics of the knee is not fully restored after single-bundle anterior cruciate ligament (ACL) reconstruction. Cadaveric experiments using knee testing machines have suggested anatomical reconstruction replacing the anteromedial and posterolateral bundles could restore knee kinematics more effectively than single-bundle reconstruction. However, practical tools to objectively assess knee rotational laxities clinically have not been available. We used an optically based computer-assisted navigation system to measure the tibiofemoral motion kinematics in four fresh whole cadavers. Standard clinical knee laxity tests (anterior drawer, Lachman, and pivot shift) were performed and the kinematics described in terms of tibial axial rotation and anteroposterior translation. Data were obtained for intact knees after excision of the ACL and sequential reconstruction of the anteromedial and posterolateral bundles. In the ACL-deficient knee, the mean maximum tibial rotation during the pivot shift test was 27 degrees and mean maximum translation 11 mm. Reconstruction of the anteromedial bundle reduced the rotational component to 18 degrees and translation to 7 mm. Reconstruction of the posterolateral bundle reduced rotation to 14 degrees . This pilot study suggests computer assisted navigation could provide a practical method to objectively measure the pivot shift and may be used clinically to demonstrate differences in the control of tibiofemoral rotation kinematics afforded by single and two-bundle ACL reconstructions.

Morphology of anterior cruciate ligament attachments for anatomic reconstruction: a cadaveric dissection and radiographic study.

PURPOSE: To define the positions of the attachments of the anteromedial (AM) and posterolateral (PL) bundles of the anterior cruciate ligament (ACL). METHODS: The shape and positions of the femoral and tibial attachments of the 2 bundles relative to bony landmarks were measured in 7 fresh-frozen, unpaired cadaveric knees by 6 independent observers. Metallic marker beads were then inserted into the defined anatomic points, and plain radiographs of the specimens were taken. We used the line described by Amis and Jakob on the tibia and the grid prepared by Bernard et al. for the femur to define AM and PL bundle attachment positions. RESULTS: In the cadaveric specimens, referencing the position of the AM bundle tibial attachment from the retro-eminence ridge (RER) resulted in the least interobserver error. On tibial radiographs, the distance between the posterior tibial cortex and the perpendicular projection of the center of the AM bundle attachment onto Amis and Jakob's line was 35.6 +/- 5.1 mm. The ratio of this distance to the length of Amis and Jakob's line (from the anterior cortex) was 36% +/- 3.8% (and 52% +/- 3.4% for the center of the PL bundle). On the femur, the center of the AM bundle was situated at 26.4% +/- 2.6%, and the center of the PL bundle at 32.3% +/- 3.9%, along the length of Blumensaat's line. CONCLUSIONS: The RER provides an easily identifiable and accurate reference point that can be used clinically. On a lateral radiograph, the positions of the tibial attachments can be referenced to Amis and Jakob's line. This method, different from Blumensaat's line, is independent of knee flexion. CLINICAL RELEVANCE: This study details anatomically and radiologically the positions of the attachments of the AM and PL bundles of the ACL. This could assist with accurate tunnel placement in reconstruction surgery and provide reference data for postoperative radiographic evaluation.

Double-stranded hamstring graft for anterior cruciate ligament reconstruction.

Current techniques for anterior cruciate ligament (ACL) reconstruction do not completely reproduce the anatomy and function of the ACL. They address only the anteromedial bundle and do not fully restore ACL function throughout the range of motion. Current grafts control anterior tibial subluxation near extension, but are less efficacious in providing rotatory stability. Recently, several authors have suggested reconstructing not just the anteromedial bundle but also the posterolateral bundle. This technical note describes a double-bundle ACL reconstruction using hamstring tendons routed through 2 tibial and 2 femoral independent tunnels.