The incidence of noncontact anterior cruciate ligament injuries in young to middle-aged athletes remains high. Despite early diagnosis and appropriate operative and nonoperative treatments, posttraumatic degenerative arthritis may develop. In a meeting in Atlanta, Georgia (January 2005), sponsored by the American Orthopaedic Society for Sports Medicine, a group of physicians, physical therapists, athletic trainers, biomechanists, epidemiologists, and other scientists interested in this area of research met to review current knowledge on risk factors associated with noncontact anterior cruciate ligament injuries, anterior cruciate ligament injury biomechanics, and existing anterior cruciate ligament prevention programs. This article reports on the presentations, discussions, and recommendations of this group.

Understanding and Preventing Noncontact Anterior Cruciate Ligament Injuries A Review of the Hunt Valley II Meeting, January 2005

Objective

The adduction moment at the knee during gait is the primary determinant of medial-tolateral load distribution. If the adduction moment contributes to progression of osteoarthritis (OA), then patients with advanced medial tibiofemoral OA should have higher adduction moments. The present study was undertaken to investigate the hypothesis that the adduction moment normalized for weight and height is associated with medial tibiofemoral OA disease severity after controlling for age, sex, and pain level, and to examine the correlation of serum hyaluronan (HA) level with disease severity and with the adduction moment in a subset of patients.



Methods

Fifty-four patients with medial tibiofemoral OA underwent gait analysis and radiographic evaluation. Disease severity was assessed using the Kellgren-Lawrence (K-L) grade and medial joint space width. In a subset of 23 patients with available sera, HA was quantified by sandwich enzyme-linked immunosorbent assay. Pearson correlations, a random effects model, and multivariate regression models were used.



Results

The adduction moment correlated with the K-L grade in the left and right knees (r = 0.68 and r = 0.60, respectively), and with joint space width in the left and right knees (r = -0.45 and r = -0.47, respectively). The relationship persisted after controlling for age, sex, and severity of pain. The partial correlation between K-L grade and adduction moment was 0.71 in the left knees and 0.61 in the right knees. For every 1.0-unit increase in adduction moment, there was a 0.63-mm decrease in joint space width. In the subset of patients in whom serum HA levels were measured, HA levels correlated with medial joint space width (r = -0.55), but not with the adduction moment.



Conclusion

There is a significant relationship between the adduction moment and OA disease severity. Serum HA levels correlate with joint space width but not with the adduction moment. Longitudinal studies will be necessary to determine the contribution of the adduction moment, and its contribution in conjunction with metabolic markers, to progression of medial tibiofemoral OA.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/1529-0131%28199807%2941%3A7%3C1233%3A%3AAID-ART14%3E3.0.CO%3B2-L

Knee adduction moment, serum hyaluronan level, and disease severity in medial tibiofemoral osteoarthritis

Anterior cruciate ligament tears, common among athletes, are functionally disabling; they predispose the knee to subsequent injuries and the early onset of osteoarthritis. A total of 3810 studies published between January 1994 and the present were identified and reviewed to determine the current state of knowledge regarding the treatment of anterior cruciate ligament injuries. Part 1 of this article focused on studies pertaining to the biomechanical behavior of the anterior cruciate ligament, the prevalence of and risk factors for injuries related to it, the natural history of the ligament-deficient knee, injuries associated with anterior cruciate ligament disruption, indications for the treatment of anterior cruciate ligament injuries, as well as nonoperative and operative treatments. Part 2 includes technical aspects of anterior cruciate ligament surgery, bone tunnel widening, graft healing, rehabilitation after anterior cruciate ligament reconstruction, and the effects of sex, age, and activity level o...

Treatment of Anterior Cruciate Ligament Injuries, Part I:

Very few subjects in contemporary orthopaedic surgery have evoked as much controversy, thought, and opinion as that of when and how to optimally reconstruct the anterior cruciate ligament of the knee. Fueled by an annual incidence of acute rupture of the anterior cruciate ligament that has been estimated to be one in 3000 in the American population—approximately 95,000 new injuries each year196—and combined with the fact that more than 50,000 knees that have such an injury are reconstructed annually in the United States alone149, it is not surprising that there has been a virtual explosion of literature on this topic. During the last twenty years, more than 2000 scientific articles on the anterior cruciate ligament have been published, including numerous excellent reviews47,149,151,255,282,294 and textbooks72,89,145. It is a challenging task to attempt to synthesize these sources and to try to resolve the conflicts that are inherent in such a massive body of information. Although many relevant issues will continue to be debated until better basic-science and clinical information becomes available, a number of scientifically supported concepts can be identified within the existing knowledge base. This knowledge can help orthopaedic surgeons to understand the reasons for previous and current successes and failures of reconstruction of the anterior cruciate ligament, and it can help them to plan the care of patients who have an injury of the ligament.

In the present review, the current scientific understanding of reconstruction of the anterior cruciate ligament is discussed in a sequence based on the order in which clinical decisions are made. An overview of the normal function of the knee joint and the anterior cruciate ligament is followed by a discussion of decisions that must …

The science of reconstruction of the anterior cruciate ligament.

Purpose of ReviewThis review examines recent in-vivo studies of ambulation and discusses the fundamental role of mechanics of ambulation in the initiation and progression of osteoarthritis at the knee.Recent FindingsRecent studies have supported earlier findings that a high adduction moment at the k

The role of ambulatory mechanics in the initiation and progression of knee osteoarthritis.

Lower limb alignment and foot angle are related to stance phase knee adduction in normal subjects: a critical analysis of the reliability of gait analysis data.

The purpose of this study was to evaluate anterior cruciate ligament allograft reconstruction in skeletally immature athletes. Eight patients (mean age, 13 years, 6 months; range, 10 to 15 years) with radiographic documentation of open growth plates had anterior cruciate ligament repair and reconstruction with fascia lata or Achilles tendon allograft tissue. A 7-mm graft was centrally placed across the tibial physes and in an over-the-top position on the femur. All patients returned for followup a mean of 58 months (range, 22 to 94) postoperatively. All had an immediate knee motion and rehabilitation exercise program. The results were rated on a comprehensive rating system that assessed 20 variables. At followup, all patients showed closure of the growth plates. The difference in lower limb length, measured on scanograms, was not clinically significant. On KT-1000 arthrometer testing, 5 patients had less than 3 mm of increased anterior-posterior displacement (normal knee minus reconstructed knee) and 3 patients had between 3 and 5 mm. The final overall ratings were 6 excellent, 1 good, and 1 fair. The procedure is infrequently used, but appears to have merit in select, skeletally immature athletes who desire not to modify athletic activity or when associated meniscal repairs warrant consideration for reconstruction.

Anterior Cruciate Ligament Allograft Reconstruction in the Skeletally Immature Athlete

Although there is a higher relative incidence of anterior cruciate ligament injuries in female than in comparable male athletes according to the literature, the majority of populations studied after reconstruction are male-dominated. We wished to determine whether a selection bias for reconstruction based on sex is warranted according to complications and outcome. Ninety-four patients (47 of each sex) were matched for chronicity of injury, age, preoperative sports activity levels, articular cartilage condition, and months of followup. All had patellar tendon autogenous reconstruction and a similar program of immediate knee motion and early return to function. The results were rated with the Cincinnati Knee Rating System. At a mean of 26 months postoperatively, there were no significant differences for complications or outcome between men and women. Women required an average of six more rehabilitation visits than men; however, none required additional surgery for knee motion complications and the rate of patellofemoral crepitus conversion was only 7%, lower than that found for men (15%). The overall failure rate was low, only 6% for women and 4% for men. We concluded that the functional rehabilitation program was effective, postoperative complications were few, and no scientific basis exists to use sex alone as a selection criteria for anterior cruciate ligament reconstruction.

A Rigorous Comparison Between the Sexes of Results and Complications After Anterior Cruciate Ligament Reconstruction

Five patients with symptomatic knee hyperextension thrusting patterns due to posterolateral ligament complex injury underwent gait analysis before and after a gait retraining program. Patients were trained to avoid knee hyperextension by 1) walking with their knees slightly flexed throughout stance, 2) maintaining ankle dorsiflexion in early stance, and 3) maintaining an erect trunk-hip attitude during stance. Kinematic and kinetic measurements were obtained using automated gait analysis. Four of the five patients significantly reduced hyperextension at the knee and abnormal motion patterns at the hip and ankle. Patients showed increases in knee flexion throughout stance conversions of knee flexion-extension moments to more normal biphasic patterns with a 79% decrease in extension moments at terminal extension, and a 22% decrease in knee adduction moments. Posttraining values also showed a 30% decrease in the calculated medial tibiofemoral loads (P < 0.05). At the hip, there were significant decreases in abduction and adduction moments (36% and 18%, respectively, P < 0.01). Ankle plantar flexion motion decreased significantly by 42% (P < 0.01). Gait retraining can alter the biomechanics of hip, knee, and ankle function to approximately normal levels, and therefore is recommended before ligament reconstruction because abnormal knee motions, if resumed postoperatively, can stretch soft tissue reconstructions.

Michelle Andrews

Papers

Lower limb alignment and foot angle are related to stance phase knee adduction in normal subjects: a critical analysis of the reliability of gait analysis data.

Anterior Cruciate Ligament Allograft Reconstruction in the Skeletally Immature Athlete

A Rigorous Comparison Between the Sexes of Results and Complications After Anterior Cruciate Ligament Reconstruction

Knee hyperextension gait abnormalities in unstable knees. Recognition and preoperative gait retraining.