Radiographic landmarks for surgical reconstruction of the anterolateral ligament of the knee

© 2014, Springer-Verlag Berlin Heidelberg. Purpose: To determine the radiographic landmarks of the anterolateral ligament (ALL) on the femur and tibia to assist in intraoperative graft placement during ALL reconstruction. Methods: The footprints of the ALL, fibular collateral ligament (FCL), popliteus insertion, lateral gastrocnemius insertion, and Gerdy’s tubercle were isolated and centrally marked with tantalum beads in thirteen fresh-frozen cadaveric knees. Measurements were taken from the true lateral fluoroscopic images. On the femur, the mean distances from the ALL origin to the FCL origin and from the ALL origin to the popliteus insertion were measured. On the tibia, the mean distances from the ALL insertion to Gerdy’s tubercle and from the ALL insertion to the lateral tibial plateau were measured. Furthermore, radiographic descriptions of the ALL origin and insertion were developed. Results: The ALL origin on the femur averaged 3.3 ± 1.5 mm anterior–distal to the FCL origin in one anatomical variant and 5.4 ± 1.4 mm posterior–proximal to the FCL origin in a second variant. The ALL origin was 9.9 ± 2.7 mm from the popliteus insertion. The ALL origin is described as overlying the posterior femoral cortical line, between Blumensaat’s line and a line from the posterior condylar articular edge parallel to Blumensaat’s line. The ALL insertion on the tibia averaged 24.7 ± 4.5 mm posterior to Gerdy’s tubercle and 11.5 ± 2.9 mm distal to the lateral tibial plateau. The tibial ALL insertion is described between the posterior tibial cortical line and a parallel line drawn down from the apex of the tibial spine, and overlying a line drawn perpendicular to the posterior tibial cortical line starting from the apex of the posterior tibial condyles. Conclusions: Using direct lateral fluoroscopy, radiographic landmarks of the ALL origin and insertion have been described

Biomechanical Analysis of Simulated Clinical Testing and Reconstruction of the Anterolateral Ligament of the Knee

© 2015 The Author(s). Background: Anatomic anterolateral ligament (ALL) reconstruction has been proposed to assist anterior cruciate ligament (ACL) reconstruction in controlling anterolateral rotational laxity of the knee. However, the biomechanical effects have not been reported. Purpose: (1) To investigate the effect of ALL transection on rotational knee kinematics and (2) to determine the effect on knee biomechanics of ALL reconstruction procedures compared with lateral extra-articular tenodesis (LET). Study Design: Controlled laboratory study. Methods: A total of 12 cadaveric knee specimens were tested in the following sequence: (1) ACLintact, (2) anteromedial bundle of ACL sectioned (ACLamb), (3) complete ACL sectioned (ACLfull), (4) ALL sectioned (ALLsec), (5) anatomic ALL reconstruction (ALLanat), and (6) LET. Biomechanical anterior drawer and Lachman tests were performed in which a 90-N load was applied to the posterior tibia, and anterior translation was measured. A combined load to simulate the early phase of the pivot-shift test was executed in which a 5-N·m internal rotation moment was applied to a fully extended knee; anterior translation and internal rotation were measured. Results: Anterior translation increased across conditions for the biomechanical tests. Internal rotation during the simulated early-phase pivot-shift test was significantly different between ACLfull and ALLsec. Anatomic ALL reconstruction did not significantly reduce internal rotation or anterior translation during the simulated early-phase pivot-shift test. After LET, a significant decrease in anterior translation was found. There was no evidence of overconstraint of the knee with either anatomic ALL reconstruction or LET. Conclusion: The ALL demonstrated a role in controlling anterolateral laxity. LET had a composite effect in governing both anterior and rotational laxity. Anatomic ALL reconstruction did not reduce anterolateral rotational laxity. Clinical Relevance: Profiling the biomechanical characteristics of anterolateral reconstruction is integral to understanding the implications and potential benefit of such an additional procedure to ACL reconstruction

Association of ligamentous laxity, male sex, chronicity, meniscal injury, and posterior tibial slope with a high-grade preoperative pivot shift: A post hoc analysis of the STABILITY study

Background: A spectrum of anterolateral rotatory laxity exists in anterior cruciate ligament (ACL)–injured knees. Understanding of the factors contributing to a high-grade pivot shift continues to be refined. Purpose: To investigate factors associated with a high-grade preoperative pivot shift and to evaluate the relationship between this condition and baseline patient-reported outcome measures (PROMs). Study Design: Cross-sectional study; Level of evidence, 3. Methods: A post hoc analysis was performed of 618 patients with ACL deficiency deemed high risk for reinjury. A binary logistic regression model was developed, with high-grade pivot shift as the dependent variable. Age, sex, Beighton score, chronicity of the ACL injury, posterior third medial or lateral meniscal injury, and tibial slope were selected as independent variables. The importance of knee hyperextension as a component of the Beighton score was assessed using receiver operator characteristic curves. Baseline PROMs were compared between patients with and without a high-grade pivot. Results: Six factors were associated with a high-grade pivot shift: Beighton score (each additional point; odds ratio [OR], 1.17; 95% CI, 1.06-1.30; P = .002), male sex (OR, 2.30; 95% CI, 1.28-4.13; P = .005), presence of a posterior third medial (OR, 2.55; 95% CI, 1.11-5.84; P = .03) or lateral (OR, 1.76; 95% CI, 1.01-3.08; P = .048) meniscal injury, tibial slope >9° (OR, 2.35; 95% CI, 1.09-5.07; P = .03), and chronicity >6 months (OR, 1.70; 95% CI, 1.00-2.88; P = .049). The presence of knee hyperextension improved the diagnostic utility of the Beighton score as a predictor of a high-grade pivot shift. Tibial slope <9° was associated with only a high-grade pivot in the presence of a posterior third medial meniscal injury. Patients with a high-grade pivot shift had higher baseline 4-Item Pain Intensity Measure scores than did those without a high-grade pivot shift (mean ± SD, 11 ± 13 vs 8 ± 14; P = .04); however, there was no difference between groups in baseline International Knee Documentation Committee, ACL Quality of Life, Knee injury and Osteoarthritis Outcome Score, or Knee injury and Osteoarthritis Outcome Score subscale scores. Conclusion: Ligamentous laxity, male sex, posterior third medial or lateral meniscal injury, increased posterior tibial slope, and chronicity were associated with a high-grade pivot shift in this population deemed high risk for repeat ACL injury. The effect of tibial slope may be accentuated by the presence of meniscal injury, supporting the need for meniscal preservation. Baseline PROMs were similar between patients with and without a high-grade pivot shift

Lateral Extra-articular Tenodesis Reduces Failure of Hamstring Tendon Autograft Anterior Cruciate Ligament Reconstruction: 2-Year Outcomes From the STABILITY Study Randomized Clinical Trial

© 2020 The Author(s). Background: Persistent anterolateral rotatory laxity after anterior cruciate ligament (ACL) reconstruction (ACLR) has been correlated with poor clinical outcomes and graft failure. Hypothesis: We hypothesized that a single-bundle, hamstring ACLR in combination with a lateral extra-articular tenodesis (LET) would reduce the risk of ACLR failure in young, active individuals. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: This is a multicenter, prospective, randomized clinical trial comparing a single-bundle, hamstring tendon ACLR with or without LET performed using a strip of iliotibial band. Patients 25 years or younger with an ACL-deficient knee were included and also had to meet at least 2 of the following 3 criteria: (1) grade 2 pivot shift or greater, (2) a desire to return to high-risk/pivoting sports, (3) and generalized ligamentous laxity (GLL). The primary outcome was ACLR clinical failure, a composite measure of rotatory laxity or a graft rupture. Secondary outcome measures included the P4 pain scale, Marx Activity Rating Scale, Knee injury Osteoarthritis and Outcome Score (KOOS), International Knee Documentation Committee score, and ACL Quality of Life Questionnaire. Patients were reviewed at 3, 6, 12, and 24 months postoperatively. Results: A total of 618 patients (297 males; 48%) with a mean age of 18.9 years (range, 14-25 years) were randomized. A total of 436 (87.9%) patients presented preoperatively with high-grade rotatory laxity (grade 2 pivot shift or greater), and 215 (42.1%) were diagnosed as having GLL. There were 18 patients lost to follow-up and 11 who withdrew (~5%). In the ACLR group, 120/298 (40%) patients sustained the primary outcome of clinical failure, compared with 72/291 (25%) in the ACLR+LET group (relative risk reduction [RRR], 0.38; 95% CI, 0.21-0.52; P \u3c.0001). A total of 45 patients experienced graft rupture, 34/298 (11%) in the ACLR group compared with 11/291 (4%) in the ACL+LET group (RRR, 0.67; 95% CI, 0.36-0.83; P \u3c.001). The number needed to treat with LET to prevent 1 patient from graft rupture was 14.3 over the first 2 postoperative years. At 3 months, patients in the ACLR group had less pain as measured by the P4 (P =.003) and KOOS (P =.007), with KOOS pain persisting in favor of the ACLR group to 6 months (P =.02). No clinically important differences in patient-reported outcome measures were found between groups at other time points. The level of sports activity was similar between groups at 2 years after surgery, as measured by the Marx Activity Rating Scale (P =.11). Conclusion: The addition of LET to a single-bundle hamstring tendon autograft ACLR in young patients at high risk of failure results in a statistically significant, clinically relevant reduction in graft rupture and persistent rotatory laxity at 2 years after surgery. Registration: NCT02018354 (ClinicalTrials.gov identifier)

Patient appropriateness for total knee arthroplasty and predicted probability of a good outcome

Objectives One-fifth of total knee arthroplasty (TKA) recipients experience a suboptimal outcome. Incorporation of patients’ preferences in TKA assessment may improve outcomes. We determined the discriminant ability of preoperative measures of TKA need, readiness/willingness and expectations for a good TKA outcome.Methods In patients with knee osteoarthritis (OA) undergoing primary TKA, we preoperatively assessed TKA need (Western Ontario-McMaster Universities OA Index (WOMAC) Pain Score and Knee injury and Osteoarthritis Outcome Score (KOOS) function, arthritis coping), health status, readiness (Patient Acceptable Symptom State, depressive symptoms), willingness (definitely yes—yes/no) and expectations (outcomes deemed ‘very important’). A good outcome was defined as symptom improvement (met Outcome Measures in Rheumatology and Osteoarthritis Research Society International (OMERACT–OARSI) responder criteria) and satisfaction with results 1 year post TKA. Using logistic regression, we assessed independent outcome predictors, model discrimination (area under the receiver operating characteristic curve, AUC) and the predicted probability of a good outcome for different need, readiness/willingness and expectations scenarios.Results Of 1,053 TKA recipients (mean age 66.9 years (SD 8.8); 58.6% women), 78.1% achieved a good outcome. With TKA need alone (WOMAC pain subscale, KOOS physical function short-form), model discrimination was good (AUC 0.67, 95% CI 0.63 to 0.71). Inclusion of readiness/willingness, depressive symptoms and expectations regarding kneeling, stair climbing, well-being and performing recreational activities improved discrimination (p=0.01; optimism corrected AUC 0.70, 0.66–0.74). The predicted probability of a good outcome ranged from 44.4% (33.9–55.5) to 92.4% (88.4–95.1) depending on level of TKA need, readiness/willingness, depressive symptoms and surgical expectations.Conclusions Although external validation is required, our findings suggest that incorporation of patients’ TKA readiness, willingness and expectations in TKA decision-making may improve the proportion of recipients that experience a good outcome