Bohdanna T. Zazulak

Deficits in Neuromuscular Control of the Trunk Predict Knee Injury Risk A Prospective Biomechanical-Epidemiologic Study

Background Female athletes are at significantly greater risk of anterior cruciate ligament (ACL) injury than male athletes in the same high-risk sports. Decreased trunk (core) neuromuscular control may compromise dynamic knee stability. Hypotheses (1) Increased trunk displacement after sudden force release would be associated with increased knee injury risk; (2) coronal (lateral), not sagittal, plane displacement would be the strongest predictor of knee ligament injury; (3) logistic regression of factors related to core stability would accurately predict knee, ligament, and ACL injury risk; and (4) the predictive value of these models would differ between genders. Study Design Cohort study (prognosis); Level of evidence, 2. Methods In this study, 277 collegiate athletes (140 female and 137 male) were prospectively tested for trunk displacement after a sudden force release. Analysis of variance and multivariate logistic regression identified predictors of risk in athletes who sustained knee injury. Results Twenty-five athletes (11 female and 14 male) sustained knee injuries over a 3-year period. Trunk displacement was greater in athletes with knee, ligament, and ACL injuries than in uninjured athletes (P < .05). Lateral displacement was the strongest predictor of ligament injury (P = .009). A logistic regression model, consisting of trunk displacements, proprioception, and history of low back pain, predicted knee ligament injury with 91% sensitivity and 68% specificity (P = .001). This model predicted knee, ligament, and ACL injury risk in female athletes with 84%, 89%, and 91% accuracy, but only history of low back pain was a significant predictor of knee ligament injury risk in male athletes. Conclusions Factors related to core stability predicted risk of athletic knee, ligament, and ACL injuries with high sensitivity and moderate specificity in female, but not male, athletes.

The Effects of Core Proprioception on Knee Injury A Prospective Biomechanical-Epidemiological Study

Background In sports involving pivoting and landing, female athletes suffer knee injury at a greater rate than male athletes. Hypotheses Proprioceptive deficits in control of the bodys core may affect dynamic stability of the knee. Female, but not male, athletes who suffered a knee injury during a 3-year follow-up period would demonstrate decreased core proprioception at baseline testing as compared with uninjured athletes. Study Design Cohort study (prognosis); Level of evidence, 2. Methods Study subjects were 277 collegiate athletes (140 female, 137 male) who were prospectively tested for core proprioception by active and passive proprioceptive repositioning. Athletes were monitored for injury for 3 years. An ANOVA and multivariate logistic regression were used to test whether core proprioception was related to knee injuries in athletes. Results Twenty-five athletes sustained knee injuries (11 women, 14 men). Deficits in active proprioceptive repositioning were observed in women with knee injuries (2.2°) and ligament/meniscal injuries (2.4°) compared with uninjured women (1.5°, P ≤ .05). There were no differences in average active proprioceptive repositioning error between injured men and uninjured men (P ≥ .05). Uninjured women demonstrated significantly less average error in active proprioceptive repositioning than uninjured men (1.5° vs 1.7°, P ≤ .05). For each degree increase in average active proprioceptive repositioning error, a 2.9-fold increase in the odds ratio of knee injury was observed, and a 3.3-fold increase in odds ratio of ligament/meniscal injury was observed (P ≤ .01). Active proprioceptive repositioning predicted knee injury status with 90% sensitivity and 56% specificity in female athletes. Conclusions Impaired core proprioception, measured by active proprioceptive repositioning of the trunk, predicted knee injury risk in female, but not male, athletes.

Effects of the Menstrual Cycle on Anterior Cruciate Ligament Injury Risk A Systematic Review

Several theories have been proposed to explain the 3- to 6-fold gender difference in the incidence of anterior cruciate ligament injuries. One potential theory for the increased incidence is based on gender-related hormonal differences between men and women, especially after puberty and the onset of menses in the female athlete. The purpose of this systematic review was to compile and systematically analyze the published literature to determine if the menstrual cycle is associated with anterior cruciate ligament injury risk and to provide an objective comparison of the published results. Investigations were included in the systematic review if the report included associations between the menstrual cycle and noncontact anterior cruciate ligament injuries in female athletes. Abstracts and unpublished studies were excluded. Seven articles were identified that met the systematic review inclusion criteria. The 7 reviewed studies favored an effect of the first half, or preovulatory phase, of the menstrual cycle for increased anterior cruciate ligament injuries. The 6 studies that separated the non—oral contraceptive and oral contraceptive data also favored an effect of the first half of the menstrual cycle for increased anterior cruciate ligament injuries. The clinical relevance of this finding is that female athletes may be more predisposed to anterior cruciate ligament injuries during the preovulatory phase of the menstrual cycle. These findings may lead to potential interventions targeted toward this phase of the menstrual cycle to reduce the incidence of anterior cruciate ligament injury.

The effects of the menstrual cycle on anterior knee laxity: A systematic review

Female athletes are at a 4- to 6-fold increased risk of anterior cruciate ligament (ACL) injury compared with male athletes. There are several medical, emotional and financial burdens associated with these injuries. Sex hormones may be involved in the ACL injury disparity, with potential associations reported between phases of the menstrual cycle and ACL injury rates. The reported relationships between ACL injury and menstrual status may be related to associated changes in ligament mechanical properties from cyclic fluctuations of female sex hormones. A PubMed electronic database literature search, including MEDLINE (1966‐2005) and CINAHL (1982‐2005), with the search terms ‘menstrual cycle’ and ‘knee laxity’ was used for this systematic review. Studies were included in this systematic review if they were prospective cohort studies and investigated the association between the menstrual cycle and anterior knee laxity in females.Nine prospective cohort studies, published as 11 articles, were included in the systematic review. Six of nine studies reported no significant effect of the menstrual cycle on anterior knee laxity in women. Three studies observed significant associations between the menstrual cycle and anterior knee laxity. These studies all reported the finding that laxity increased during the ovulatory or post-ovulatory phases of the cycle. A meta-analysis, which included data from all nine reviewed studies, corroborated this significant effect of cycle phase on knee laxity (F-value = 56.59, p = 0.0001). In the analyses, the knee laxity data measured at 10‐14 days was > 15‐28 days which was >‐9 days.Future studies testing the relationship between the menstrual cycle and potentially associated parameters should consider the limitations outlined in this article and control for potential biases and confounders. Power analyses should be utilised. Subjects should be randomly entered into the studies at alternate points in the cycle, and standard and consistent data acquisition and reporting methods should be utilised. Future studies should clearly define what constitutes a ‘normal’ cycle and appropriate control subjects should be utilised. Furthermore, there is a need to define cycle phase (and timing within cycle phase) with actual hormone levels rather than a day of the cycle. Although hormone confirmations were provided in many of the studies that selected specific days to depict a particular cycle for all women, it is unknown from these data if they truly captured times of peak hormone values in all women.A combined systematic review and meta-analysis of the literature indicate that the menstrual cycle may have an effect on anterior-posterior laxity of the knee; however, further investigation is needed to confirm or reject this hypothesis.

A review of electromyographic activation levels, timing differences, and increased anterior cruciate ligament injury incidence in female athletes

Deficits in dynamic neuromuscular control of the knee may contribute to the higher incidence of anterior cruciate ligament (ACL) injury in female athletes. There is evidence that neuromuscular training alters muscle firing patterns, as it decreases landing forces, improves balance, and reduces ACL injury incidence in female athletes. The purpose of this review is to summarise the evidence for altered muscular activation and timing relative to ACL injury risk in female athletes.

Neuromuscular control of trunk stability: clinical implications for sports injury prevention.

Recent prospective evidence supports the hypothesis that impaired trunk control is a contributing factor to sports injuries of the spine as well as to segments of the kinetic chain. The current concepts regarding neuromuscular control of trunk stability are best described from a systems engineering perspective. In the analysis of current neuromuscular training protocols for sports injury prevention, these principles are applied to identify components that optimize neuromuscular control of trunk stability. Current perspectives of neuromuscular learning can be applied clinically to aid in the formulation of injury prevention strategies.

Comparison of Trunk Proprioception Between Patients With Low Back Pain and Healthy Controls

OBJECTIVE To determine whether proprioceptive impairments exist in patients with low back pain (LBP). We hypothesized that patients with LBP would exhibit larger trunk proprioception errors than healthy controls. DESIGN Case-control study. SETTING University laboratory. PARTICIPANTS 24 patients with nonspecific LBP and 24 age-matched healthy controls. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES We measured trunk proprioception in all 3 anatomical planes using motion perception threshold, active repositioning, and passive repositioning tests. RESULTS LBP patients had significantly greater motion perception threshold than controls (P<.001) (1.3+/-0.9 degrees vs 0.8+/-0.6 degrees ). Furthermore, all subjects had the largest motion perception threshold in the transverse plane (P<.001) (1.2+/-0.7 degrees vs 1.0+/-0.8 degrees for all other planes averaged). There was no significant difference between LBP and healthy control groups in the repositioning tasks. Errors in the active repositioning test were significantly smaller than in the passive repositioning test (P=.032) (1.9+/-1.2 degrees vs 2.3+/-1.4 degrees ). CONCLUSIONS These findings suggest that impairments in proprioception may be detected in patients with LBP when assessed with a motion perception threshold measure.

A Multidisciplinary Approach to the Evaluation, Reconstruction and Rehabilitation of the Multi-Ligament Injured Athlete

AbstractKnee dislocations with multi-ligamentous involvement are potentially limb-threatening injuries that require extensive surgical and rehabilitative intervention. These knee injuries, such as combined anterior cruciate ligament, posterior cruciate ligament, medial collateral ligament and/or lateral collateral ligament injuries, are devastating injuries with results that vary from total disability to nearly full recovery of function. Recent surgical advances, including the use of allograft tissues, have increased the efficacy of these procedures while posing new challenges. By combining scientifically based surgical and rehabilitative approaches, improved outcomes in these difficult cases are being reported in the orthopaedic literature.This review details the epidemiology and biomechanics of these serious knee ligament injuries. In addition, state-of-the-art surgical and rehabilitative techniques will be outlined. Clinical and diagnostic imaging evaluation of these knee injuries is reviewed in order to plan and execute the surgical and rehabilitative practices. We review the basic science, surgical and rehabilitative theories and practices associated with bringing patients with these serious knee injury injuries to full recovery, and detail the development of strategies for developing protocols to address these complicated cases.

The Epidemiology of Pediatric Basketball Injuries Presenting to US Emergency Departments 2000-2006

Background: There is limited published research on the epidemiology of basketball injuries treated in US emergency departments (EDs). Hypothesis: Age and sex patterns exist for the most common pediatric basketball injuries treated in EDs. Study Design: Descriptive epidemiology study. Methods: Data from the National Electronic Injury Surveillance System and the National Sporting Goods Association were used to calculate national injury incidence rates and 95% confidence intervals of pediatric basketball injuries. Results: An estimated 325 465 annual visits were made to US EDs for pediatric basketball-related injuries from 2000 to 2006. The 5 most common injuries were ankle sprains (21.7%), finger sprains (8.0%), finger fractures (7.8%), knee sprains (3.9%), and facial lacerations (3.9%). Among persons aged 12 to 17 years, girls had a higher rate of knee sprains than boys (P < 0.001), but this association did not exist among those aged 7 to 11 years (P = 0.27). Boys had a higher rate of facial lacerations than girls (P < 0.01). Among persons aged 12 to 17 years, girls had a higher rate of finger sprains (P < 0.01). For both boys and girls, the rate of the 5 most common basketball injuries was higher among those aged 12 to 17 years compared with those aged 7 to 11 years (P < 0.01). Conclusions: The annual number of basketball-related pediatric ED visits approaches a third of a million and demonstrates the extent of the public health problem that injuries in this sport pose. Distinct sex and age patterns were observed. Clinical Relevance: The study findings provide important information on basketball injury rates that may be used for targeting prevention interventions by sex and age group.

Enchondroma in a Running Athlete With Persistent Mid-Thigh Pain

The patient was a 22-year-old male who developed right mid-thigh pain after increasing his running mileage in a short period. Anterior-posterior and lateral radiographs of the femur were completed and interpreted as normal, and the patient was diagnosed with a muscle strain. Three months later the patient was seen by a sports medicine physician because of persistent right mid-thigh pain with running. Repeat radiographs revealed periosteal thickening of the medial cortex of the right femur consisten with a stress reaction and subtle irregular calcifications in the central diaphysis of the femur. The patient was diagnosed with a femoral shaft stress fracture and referred for magnetic resonance imaging, which revealed a lobular lesion occupying the marrow space of the femoral diaphysis that measure approximately 6.5 cm in the craniocaudal dimension. The patient was diagnosed with an echondroma of the distal femoral shaft. After pursuing a non-surgical course of care, the patient opted for surgical interventi...