Functional scores and prosthetic implant placement are different for navigated medial UKA left in varus alignment.

PURPOSE: The purpose of this study was to analyze the clinical outcomes and radiologic position of the knee in two groups of patients after medial unicompartmental knee arthroplasty (UKA): one group with residual varus axis (RVA) alignment and other one with neutral mechanical axis (NMA) of the lower limb. METHODS: All patients who underwent UKA between January 2015 and January 2018 were evaluated retrospectively. Inclusion criteria were: medial UKA for isolated medial femoro-tibial osteoarthritis, a varus deformity of < 15°, and a minimal follow-up of 2 years. All patients had a preoperative and postoperative clinical examination with functional scores (New International Knee Score (NewIKS) and Knee injury and Osteoarthritis Outcome Score (KOOS) and radiographs. Preoperative and postoperative values for continuous outcomes were compared using the Student's t test for paired data and differences between the groups were compared with the Mann-Whitney U test. p < 0.05 was considered statistically significant. RESULTS: The RVA group consisted of 48 cases of medial UKA in 48 patients (22 females). Mean postoperative hip-knee-ankle (HKA) angle was 174.3° ± 2.8 and the corresponding mean AKI angle (tibial mechanical angle) was 82.9° ± 2.9. The NMA group consisted of 35 cases of medial UKA in 35 patients (14 females). Mean postoperative HKA angle was 178.9° ± 3 and the corresponding mean AKI angle was 85.5° ± 3.1. A significant difference was found between the two groups for the KOOS score and for global NewIKS, with a better score in the RVA group. CONCLUSIONS: RVA alignment after medial UKA results in a significant improvement in functional knee scores at 2-year post-surgery. Return to sport and recreational activities was better than in patients with postoperative NMA. LEVEL OF EVIDENCE: Level 3; retrospective cohort study.

Tibial tunnel expansion does not correlate with four-strand graft maturation after ACL reconstruction using adjustable cortical suspensory fixation.

PURPOSE: Anterior cruciate ligament reconstruction (ACLR) using a short, quadrupled semitendinosus (ST-4) autograft, fixed  with an adjustable suspensory fixation (ASF), has several potential advantages. However, the construct is suspected to generate micromotion, tunnel widening and poor graft maturation. The aim of this study was to evaluate post-operative tibial tunnel expansion, graft maturation and clinical outcomes for this type of ACLR. METHODS: One-hundred and forty-nine patients were reviewed at a minimum of 2 years following 4-ST ACLR, mean 25.6 ± 3.5 months [24-55], with clinical follow-up and MRI scans. Graft maturity of the intra-articular part of the graft and the tibial tunnel portion was assessed using Signal-to-Noise Quotient (SNQ) and Howell score. Tibial tunnel expansion, bone-graft contact and graft volume in the tibial tunnel were calculated from the MRI scans. RESULTS: Mean tibial tunnel expansion was 13 ± 16.5% [12-122]. Mean SNQ for graft within the tibial tunnel was 3.8 ± 7.1 [ - 7.7 to 39] and 2.0 ± 3.5 [ - 14 to 17] for the intra-articular portion of the graft. The Howell score for graft within the tibial tunnel was 41% Grade I, 37% Grade 2, 20% Grade 3, 2% grade 4, and for the intra-articular part 61% Grade 1, 26% Grade 2, 13% Grade 3 and 1% Grade 4. The mean tibial tunnel bone-graft contact was 81 ± 23% [0-100] and mean graft volume was 80 ± 22% [0-100]. No correlation was found between tibial tunnel expansion and graft maturity assessed at both locations. Graft maturity was correlated with higher graft-bone contact and graft volume in the tibial tunnel (p < 0.05). CONCLUSIONS: ST-4 ACLR with ASF had low levels of tunnel enlargement at 2 years. No correlation was found between graft maturation and tibial tunnel expansion. Graft maturity was correlated with graft-bone contact and graft volume in the tibial tunnel. LEVEL OF EVIDENCE: Level III.

Two-year postoperative MRI appearances of anterior cruciate ligament hamstrings autografts are not correlated with functional outcomes, anterior laxity, or patient age.

AIMS: MRI has been suggested as an objective method of assessing anterior crucate ligament (ACL) graft "ligamentization" after reconstruction. It has been proposed that the MRI appearances could be used as an indicator of graft maturity and used as part of a return-to-sport assessment. The aim of this study was to evaluate the correlation between MRI graft signal and postoperative functional scores, anterior knee laxity, and patient age at operation. METHODS: A consecutive cohort of 149 patients who had undergone semitendinosus autograft ACL reconstruction, using femoral and tibial adjustable loop fixations, were evaluated retrospectively postoperatively at two years. All underwent MRI analysis of the ACL graft, performed using signal-to-noise quotient (SNQ) and the Howell score. Functional outcome scores (Lysholm, Tegner, International Knee Documentation Committee (IKDC) subjective, and IKDC objective) were obtained and all patients underwent instrumented side-to-side anterior laxity differential laxity testing. RESULTS: Two-year postoperative mean outcome scores were: Tegner 6.5 (2 to 10); Lysholm 89.8 (SD 10.4; 52 to 100); and IKDC subjective 86.8 (SD 11.8; 51 to 100). The objective IKDC score was 86% A (128 patients), 13% B (19 patients), and 1% C (two patients). Mean side-to-side anterior laxity difference (134 N force) was 0.6 mm (SD 1.8; -4.1 to 5.6). Mean graft SNQ was 2.0 (SD 3.5; -14 to 17). Graft Howell scores were I (61%, 91 patients), II (25%, 37 patients), III (13%, 19 patients), and IV (1%, two patients). There was no correlation between either Howell score or SNQ with instrumented anterior or Lysholm, Tegner, and IKDC scores, nor was any correlation found between patient age and ACL graft SNQ or Howell score. CONCLUSION: The two-year postoperative MRI appearances of four-strand, semitendinosus ACL autografts (as measured by SNQ and Howell score) do not appear to have a relationship with postoperative functional scores, instrumented anterior laxity, or patient age at surgery. Other tools for analysis of graft maturity should be developed. Cite this article: Bone Jt Open 2021;2(8):569-575.

Combined Anterior Cruciate Ligament Primary Repair With an Autograft Reconstruction.

Anterior cruciate ligament (ACL) reconstruction using an autograft gives good results that could provide improved failure rates. ACL augmentation saving the remnant has demonstrated advantages, such as saving vascular supply and nerve receptors, which could be useful for healing. Conversely, isolated repair techniques are gaining interest but do not give good results because structural augmentation is necessary to reinforce the repair and expect healing. We describe a technique combining the advantages of both techniques with an autograft using the semitendinosus and repair of the remnant. This combined technique allows protection and redirection of the remnant, improves graft incorporation, and covers more graft by suturing the remnant around an autologous graft.

The Migratory Cortical Button: A Rare Case of Hypersensitivity to Titanium after an Anterior Cruciate Ligament Reconstruction.

Allergy to metal, especially to titanium, is a poorly known subject in orthopedic surgery and is mostly found after arthroplasty. Here, we describe an original case of titanium allergy that developed after an anterior cruciate ligament (ACL) reconstruction of the left knee in a patient with a history of severe atopic dermatitis. Three years after the surgery, he returned to the clinic with the femoral cortical button in his hand; he removed the device from the wound when the skin spontaneously opened at the lateral part of the thigh. The wound healed with dressings without use of any antibiotics. Clinical and functional results were favorable and magnetic resonance imaging signal of the graft was normal. We ruled out the possibility of infection and the final diagnosis was allergy to titanium. This case demonstrates the need to investigate the presence of allergy to metal, including titanium, before an ACL reconstruction.

Clinical and Functional Outcomes of Anterior Cruciate Ligament Reconstruction at a Minimum of 2 Years Using Adjustable Suspensory Fixation in Both the Femur and Tibia: A Prospective Study.

BACKGROUND: The success of anterior cruciate ligament (ACL) reconstruction requires reliable and rigid graft fixation. Cortical suspensory fixation (CSF) devices have become an acceptable alternative to interference screws for soft tissue ACL grafts. However, CSF devices have been reported to be associated with tunnel widening and increased postoperative anterior laxity compared with interference screw fixation. Adjustable CSF devices were introduced to avoid these problems but have been associated with graft lengthening and inconsistent outcomes. PURPOSE: To (1) report the side-to-side difference (SSD) in anterior laxity at 150 N, clinical scores, and failure rates 2 years after ACL reconstruction with 4-strand semitendinosus autografts using an adjustable CSF device and (2) determine the preoperative factors associated with clinical outcomes. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: A total of 131 patients who had undergone primary ACL reconstruction, performed with 4-strand semitendinosus grafts that were secured using Pullup adjustable-length CSF devices with femoral and tibial fixation techniques, were prospectively enrolled in this study; 34 patients were excluded because of contralateral instability or ipsilateral knee injuries that required additional surgery. This left a cohort of 97 patients who were evaluated preoperatively and at 6, 12, and 24 months. The evaluation consisted of measuring the SSD in anterior laxity and patient-reported outcome scores (International Knee Documentation Committee [IKDC] and Lysholm scores). Regression analyses were performed to determine associations between these outcomes and 9 preoperative variables. RESULTS: Only 2 patients could not be reached, 2 could not be evaluated because of contralateral ACL tears, and 2 had graft failure. At 2-year follow-up, the remaining 91 patients had a mean SSD in anterior laxity of 0.8 ± 1.8 mm (range, -4.2 to 5.3 mm), mean IKDC score of 87.6 ± 10.6 (range, 43.7-100.0), and mean Lysholm score of 90.8 ± 9.3 (range, 56.0-100.0). At final follow-up, compared with knees with partial ruptures, those with complete ruptures had equivalent laxity (P = .266) and Lysholm scores (P = .352) but lower IKDC scores (P = .009). Multivariable regression revealed that the IKDC score decreased with increased preoperative laxity (ß = -1.35 [95% CI, -2.48 to -0.23]; P = .019). CONCLUSION: The novel adjustable-length CSF device produced satisfactory anterior laxity and clinical outcomes, with a failure rate of 2.1%, which compare favorably with those reported for nonadjustable CSF devices.

Editorial Commentary: Anterior Cruciate Ligament Augmentation: A Bold, Technically Demanding Surgical Technique But Don't Forget to Evaluate the Benefit-Risk Ratio!

Preserving the remnant tissues in anterior cruciate ligament reconstruction, commonly referred to as anterior cruciate ligament augmentation, is an option in the "surgery à la carte" menu that the surgeon may choose from to adapt the surgical technique depending on each patient's specific needs. When possible, preserving this remnant offers definite benefits: improved vascularization, presence of neurosensors, and even mechanical advantages. However, this technique may prove to be tricky, especially when the intercondylar notch is not clearly visible and when the surgeon lacks experience. The benefit-risk ratio must be carefully weighed for each case.

The capsular line reference, a new arthroscopic reference for posterior/anterior femoral tunnel positioning in anterior cruciate ligament reconstruction.

BACKGROUND: Femoral malposition is the first cause for graft rupture during ACL reconstruction. Arthroscopic landmarks can be difficult to identify. So, landmark has to be found for reliable tunnel placement. A proximal-distal reference was described as "Apex reference" reported by Hart et al. but no posterior/anterior reference exists in the literature. The purpose of this study was to do a 3D CT-scan assessment of the femoral tunnel positioning using the Capsular Line Reference (CLR) as a landmark for posterior/anterior placement in ACL reconstruction. We hypothesized the CLR could provide a precise and reliable antero/posterior femoral tunnel positioning less than 2 mm from the Bernard & Hertel posterior quarter. METHODS: Seven cadaveric knee specimens with a mean age of 79.2 ± 11 years were used. Using standard approaches, the CLR was identified corresponding to a white line (the capsule) appearing at the posterior border of the femoral condyle after bony debridement of the medial and posterior part of the lateral femoral condyle. The center of the tunnel was marked. An inside-out technique with anteromedial drilling technique was performed using an 8-mm diameter reamer. The distal femurs were sawed and a CT-scan was done for each specimen to obtain 3-dimensional image reconstructions. These 3D reconstructions were analyzed to measure the position tunnel center on the posterior/anterior axis and the distance from the posterior/anterior quadrant according to the Bernard & Hertel method. RESULTS: The mean position for the posterior/anterior axis was 27.0 ± 1.8% (25-28.9) with a median of 26.9%. The position from the first quarter of the Bernard & Hertel method was 0.9 ± 0.8 mm (0-1.8) with a median of 0.8 mm. CONCLUSION: The CLR is a reliable and reproducible arthroscopic landmark to place the femoral tunnel for ACL reconstruction in the anterior/posterior axis. Proximal/distal position depends on the choice of the surgeon to reproduce anteromedial or posterolateral fibers.

Suspensory Fixation Device for Use With Bone-Patellar Tendon-Bone Grafts.

Good to excellent results at long-term follow-up have been published for bone-patellar tendon-bone (BTB) graft anterior cruciate ligament reconstruction. Fixation using screws historically has been the most common choice for femoral and tibial bone blocks, but screws present several disadvantages, which include the risk of blowout (for which prevention implies having to shift the position of the tunnel anteriorly), as well as lesions of the bone blocks and tendons. This article describes a technique using Pullup BTB adjustable-loop length suspensory fixation (SBM, Lourdes, France) on the femoral and tibial sides. The graft is harvested and prepared classically. This device combines the advantages of suspensory fixation (precise position of the tunnel, high tensile strength), with the advantages of the adjustable loop (control of bone block position within the femoral tunnel, possibility of retightening the graft) and allows for double passage of the loop through each bone block for increased safety. So, it could represent an interesting and secure option for anatomic reconstruction of the anterior cruciate ligament when a BTB graft is chosen.

Incorporation of Hamstring Grafts Within the Tibial Tunnel After Anterior Cruciate Ligament Reconstruction: Magnetic Resonance Imaging of Suspensory Fixation Versus Interference Screws.

BACKGROUND: The success of anterior cruciate ligament (ACL) reconstruction requires solid graft incorporation within the tunnels to enable graft remodeling. Resorbable interference screws (RIS) provide limited tendon-bone contact because much of the tunnel circumference is occupied by the screw itself, while adjustable suspensory fixation (ASF) systems provide larger contact zones, which favor ligamentization. PURPOSE: To evaluate ligamentization of a 4-strand semitendinosus (4ST) graft fixed with ASF compared with RIS within the tibial bone tunnel at 6 months postoperatively using magnetic resonance imaging (MRI). STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: We prospectively enrolled 121 consecutive patients undergoing primary ACL reconstruction using a single-bundle 4ST graft. The femoral end of the graft was fixed using suspensory fixation in all knees. The tibial end of the graft was fixed using ASF in 67 knees and RIS in 54 knees. Six months postoperatively, knee laxity measurements were taken, and MRI was performed to assess graft incorporation within the tibial tunnel. RESULTS: At 6-month follow-up, MRI scans of 109 knees were available for analysis. The mean tibial tunnel enlargement in the ASF group was 2.3 ± 1.1 mm (range, 0.5-6.0 mm), while in the RIS group, it was 4.7 ± 2.8 mm (range, 0.5-19.0 mm) (P < .001). The Howell graft signal assessment findings were excellent in 97% of knees in the ASF group and in 25% of knees in the RIS group (P < .001). The mean signal-to-noise quotient (SNQ) was 0.078 ± 0.62 in the ASF group and 0.671 ± 0.83 in the RIS group (P < .001). CONCLUSION: ASF provides more favorable conditions than RIS for the incorporation and ligamentization of 4ST grafts within the tibial tunnel. The ASF system used showed very little tunnel widening, which suggests that it grants stabilization. The SNQ was also considerably better in the ASF group.

Minimally Invasive Anterior Semitendinosus Harvest: A Technique to Decrease Saphenous Nerve Injury.

Hamstring tendon harvest, especially semitendinosus harvest, has been widely used in anterior cruciate ligament reconstruction for many years. However, donor site morbidity has been described regarding the infrapatellar branch of the saphenous nerve. Minimally invasive anterior semitendinosus harvest is a simple, safe, reproducible, and elegant technique. A 2-cm vertical incision above the pes anserinus is performed 2 cm medial to the tibial anterior tubercle. The fascia superficialis is opened with a horizontal incision, and the gracilis is isolated using a retractor. The semitendinosus is grabbed with a probe, and the vincula are hooked one by one. The tendon is harvested with a closed stripper. The expansions are cut, and the tendon is detached from the bone with part of the periosteum.

An Anterior Cruciate Ligament Reconstruction Technique With 4-Strand Semitendinosus Grafts, Using Outside-In Tibial Tunnel Drilling and Suspensory Fixation Devices.

We describe an anatomic single-bundle anterior cruciate ligament reconstruction using a 4-strand semitendinosus graft fixed with 2 Pullup adjustable suspensory fixation systems (SBM, Lourdes, France). Outside-in full tibial tunnel drilling represents a secure option for length management of the graft. The preferred graft choice is a 4-strand semitendinosus autologous graft. A special technique is used to stitch the graft with a figure-of-8 stitch to load the 4 strands. The Pullup adjustable loop is equipped with 2 buttons of different sizes: a small button for the standard Pullup system on the femoral side and a large button for the Pullup XL system on the tibial side. With this method, graft tension is equally distributed among the 4 strands and the graft cannot bottom out in the tibial tunnel in case of inadequate graft length.

Patient demographics and surgical characteristics in ACL revision: a comparison of French, Norwegian, and North American cohorts.

PURPOSE: The goal of this paper is to compare patient factors, intra-operative findings, and surgical techniques between patients followed in large cohorts in France, Norway, and North America. METHODS: Data collected on 2,286 patients undergoing revision anterior cruciate ligament reconstruction (ACLR) were obtained. These data included 1,216 patients enrolled in the Multicenter ACL Revision Study (MARS) in North America, 793 patients undergoing revision ACLR and recorded in the Norwegian Knee Ligament Registry (NKLR), and 277 patients recorded in the revision ACL database of the Société Française d'Arthroscopie (SFA) in France. Data collected from each database included patient demographics (age, sex, height, and weight), graft choice and reason for failure of the primary ACLR, time from primary to revision ACLR, pre-revision patient-reported outcome scores (Knee Injury and Osteoarthritis Outcome Score, subjective International Knee Documentation Committee), associated intra-articular findings and treatments at revision, and graft choice for revision reconstruction. RESULTS: Patient demographics in the three databases were relatively similar. Graft choice for primary and revision ACLR varied significantly, with more allografts used in the MARS cohort. Hamstring autograft was favoured in the NKRL, while bone-patellar tendon-bone autograft was most common in the SFA cohort. Reasons for failure of the primary ACLR were comparable, with recurrent trauma noted in 46-56 % of patients in each of the three cohorts. Technical error was cited in 44-51 % of patients in the MARS and SFA cohorts, but was not clearly elucidated in the NKLR cohort. Biologic failure of the primary graft was more common in the MARS cohort. Differences in associated intra-articular findings were noted at the time of revision ACLR, with significantly more high-grade cartilage lesions noted in the MARS group. CONCLUSIONS: Significant differences exist between patient populations followed in revision ACL cohorts throughout the world that should be considered when applying findings from such cohorts to different patient populations. LEVEL OF EVIDENCE: Retrospective comparative study, Level III.

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.

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.

Knee laxity control in revision anterior cruciate ligament reconstruction versus anterior cruciate ligament reconstruction and lateral tenodesis: clinical assessment using computer-assisted navigation.

BACKGROUND: Rotational laxity control is one of the different options to improve functional results after anterior cruciate ligament reconstruction. Lateral extra-articular tenodesis has been proposed to reduce the rotational laxity, especially in challenging situations such as revision reconstruction after biological failure. We currently lack the practical clinical tools to objectively assess knee rotational laxities. HYPOTHESIS: Addition of a lateral tenodesis to anatomic single-bundle anterior cruciate ligament reconstruction with hamstring tendon graft could improve the knee laxity control, particularly the internal rotation, compared with a standard single-bundle anterior cruciate ligament reconstruction. STUDY DESIGN: Controlled laboratory study. METHODS: Twenty patients underwent navigated anatomic anteromedial bundle revision anterior cruciate ligament reconstruction with addition of percutaneous extra-articular tenodesis using the same hamstring tendon graft. The navigation was used to optimize femoral and tibial tunnel positions and to measure the knee kinematics in response to the anterior drawer test, Lachman test, maximum internal/external rotation test, and pivot-shift test. All patients underwent revision after failure without any technical error found or new trauma. Two sequential reconstruction protocols were used to assess the contribution of the extra-articular tenodesis and single anteromedial bundle anterior cruciate ligament reconstruction to restrain tibial translations and coupled axial rotation occurring with the manually performed clinical laxity tests. In group A, the intra-articular reconstruction was fixed first and then the lateral tenodesis was fixed, and in group B, the protocol was reversed. Measurements were performed before the reconstruction, after the first part was fixed, and after the second part was fixed in each protocol. RESULTS: At 90° of flexion, addition of lateral tenodesis had a significant effect on coupled internal rotation (P = .003). Addition of the intra-articular reconstruction to lateral tenodesis had a significant effect (P = .001) in reducing anterior tibial translation of the medial compartment, and the effect was also significant (P = .0001) in reduction of lateral compartment translation. For the rotational envelope, lateral tenodesis had a significant effect (P = .0001) in reducing maximum internal rotation at 90° of flexion. CONCLUSION: Addition of an extra-articular procedure provided no significant improvement to anterior tibial translation and improved internal tibial rotation control only at 90° of flexion.

Navigated intra-articular ACL reconstruction with additional extra-articular tenodesis using the same hamstring graft.

PURPOSE: In some complex cases, standard anterior cruciate ligament reconstruction is not enough and could lead to a new failure. Lateral extra-articular reconstruction should be added. We describe a new mini-invasive technique using the same hamstring graft for intra-articular reconstruction and lateral tenodesis, optimized with navigation. METHOD: This arthroscopic technique is precisely described, different graft setting are possible, four strands graft inside the joint and two strands for the tenodesis or two strands graft for all the whole graft. As the lateral tenodesis is not anatomic, tunnel placement could be tricky. The use of navigation system is a real advantage for this technique with optimal tunnels placement. RESULTS: No results are given. CONCLUSION: This technique is comparable to others reported previously, showing a clinical advantage and no increasing of osteoarthritis. The use of the same graft avoids collateral damages, and navigation improves the graft placement.

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.

Computer-assisted, anatomic, double-bundle anterior cruciate ligament reconstruction.

Accurate placement of the separate anteromedial bundle and posterolateral bundle bone tunnels required for anatomic, double-bundle anterior cruciate ligament reconstruction remains a concern, and the advantages the technique confers, in terms of laxity control, may be lost with incorrect tunnel positioning. We present an image-free, computer-assisted, double-bundle reconstruction technique using specifically designed software. This assists tunnel positioning and allows the behavior of virtual anteromedial and posterolateral bundle grafts to be modeled. Data on graft length change, obliquity, and possible notch impingement are fed back to the surgeon via the interactive, touch-screen navigation display. Tunnel length and obliquity may also be determined. In addition, the software allows preoperative and postoperative navigated laxity analysis, which includes objective measurement of pivot shift.