Michael R. Sitler

The Efficacy of a Semirigid Ankle Stabilizer to Reduce Acute Ankle Injuries in Basketball A Randomized Clinical Study at West Point

This randomized clinical study was designed to pro spectively determine the efficacy of a semirigid ankle stabilizer in reducing the frequency and severity of acute ankle injuries in basketball. Athletic shoe, playing surface, athlete-exposure, ankle injury history, and brace assignment were either statistically or experimen tally controlled. Participants in the study were 1601 United States Military Academy cadets with no prepar ticipation, clinical, functional, or radiographic evidence of ankle instability. Subjects experienced a total of 13,430 athlete-exposures in the 1990 and 1991 intra mural basketball seasons. Ankle injury was defined as acute trauma to the ankle ligaments that resulted in an athletes inability to participate in basketball 1 day after the injury. Use of ankle stabilizers significantly reduced the frequency of ankle injuries. Reduction in ankle in juries, however, depended on the nature of injury (fewer contact injuries occurred among those who wore braces). Injury severity was not statistically reduced, and wearing the ankle stabilizer did not affect the fre quency of knee injuries. Attitude toward ankle stabilizer use improved as use of the stabilizer increased.

The efficacy of a prophylactic knee brace to reduce knee injuries in football A prospective, randomized study at West Point

The purpose of this prospective, randomized study was to determine the efficacy of a prophylactic knee brace to reduce the frequency and severity of acute knee injuries in football in an athletic environment in which the athletic shoe, playing surface, athlete-exposure, knee injury history, and brace assignment were either statistically or experimentally controlled. The partici pants in the study were 1396 cadets at the United States Military Academy, West Point, New York, who experienced a total of 21,570 athlete-exposures in the 1986 and 1987 fall intramural tackle football seasons. The use of prophylactic knee braces significantly re duced the frequency of knee injuries, both in the total number of subjects injured and in the total number of medial collateral ligament injuries incurred. However, the reduction in the frequency of knee injuries (total and medial collateral ligament) was dependent on player position. Defensive players who wore prophylactic knee braces had statistically fewer knee injuries than players who served as controls. This was not true of offensive players who served as controls; they had statistically no difference in the number of knee injuries from players who wore prophylactic knee braces. The severity of medial collateral ligament and anterior cruciate ligament knee injuries was not significantly reduced with the use of prophylactic knee braces.

Is osteoarthritis a heterogeneous disease that can be stratified into subsets

Osteoarthritis is a heterogeneous disease characterized by variable clinical features, biochemical/genetic characteristics, and responses to treatments. To optimize palliative effects of current treatments and develop efficacious disease-modifying interventions, treatments may need to be tailored to the individual or a subset of osteoarthritic joints. The purpose of this review is to explore the current literature on the clinical and physiological variability in osteoarthritis and potential for stratifying patients. Several stratifications have been reported, including mechanism of onset, stage of disease progression, involved joints, inflammatory levels, and effusion. Most of these methods revealed two to three unique subsets of osteoarthritis. Osteoarthritic joints may be stratified by an array of variables, some transient and others consistent throughout the disease process. Future research needs to continue to explore stratification techniques since these may be the key to optimizing palliative interventions and developing disease-modifying interventions for subsets within this heterogeneous disease.

Effects of Pediatric Obesity on Joint Kinematics and Kinetics During 2 Walking Cadences

UNLABELLED Shultz SP, Sitler MR, Tierney RT, Hillstrom HJ, Song J. Effects of pediatric obesity on joint kinematics and kinetics during 2 walking cadences. OBJECTIVE To determine whether differences existed in lower-extremity joint biomechanics during self-selected walking cadence (SW) and fast walking cadence (FW) in overweight- and normal-weight children. DESIGN Survey. SETTING Institutional gait study center. PARTICIPANTS Participants (N=20; mean age +/- SD, 10.4+/-1.6y) from referred and volunteer samples were classified based on body mass index percentiles and stratified by age and sex. Exclusion criteria were a history of diabetes, neuromuscular disorder, or recent lower-extremity injury. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Sagittal, frontal, and transverse plane angular displacements (degrees) and peak moments (newton meters) at the hip, knee, and ankle joints. RESULTS The level of significance was set at P less than .008. Compared with normal-weight children, overweight children had greater absolute peak joint moments at the hip (flexor, extensor, abductor, external rotator), the knee (flexor, extensor, abductor, adductor, internal rotator), and the ankle (plantarflexor, inverter, external/internal rotators). After including body weight as a covariate, overweight children had greater peak ankle dorsiflexor moments than normal-weight children. No kinematic differences existed between groups. Greater peak hip extensor moments and less peak ankle inverter moments occurred during FW than SW. There was greater angular displacement during hip flexion as well as less angular displacement at the hip (extension, abduction), knee (flexion, extension), and ankle (plantarflexion, inversion) during FW than SW. CONCLUSIONS Overweight children experienced increased joint moments, which can have long-term orthopedic implications and suggest a need for more nonweight-bearing activities within exercise prescription. The percent of increase in joint moments from SW to FW was not different for overweight and normal-weight children. These findings can be used in developing an exercise prescription that must involve weight-bearing activity.

Association of Burners with Cervical Canal and Foraminal Stenosis

The purpose of this study was to determine whether the burner phenomenon is associated with cervical canal and foraminal stenosis in a scholastic population. Lateral cervical radiographs were reviewed for 64 athletes, 15 to 18 years of age, who had sustained at least one burner. Controls consisted of age-matched athletes who had sustained head or neck trauma without evidence of the burner phenomenon (N 32). Pavlov ratios were calculated for levels C-3 through C-6; both mean minimum and mean average ratios were determined. Available oblique radiographs from both the study (N 31) and control (N 15) groups were then used to calculate the foramen/vertebral body ratio—a measure of relative foraminal height. Significant differences were found between the burner and control groups for the mean minimum and mean average Pavlov ratios and foramen/vertebral body ratios. Scholastic athletes sustaining the burner phenomenon have an increased risk of cervical canal and foraminal stenosis as measured by the Pavlov and foramen/vertebral body ratios, respectively. The foramen/vertebral body ratio is an easily reproducible and reliable means of assessing foraminal dimensions from oblique radiographs and controls for x-ray magnification and rotation. Foraminal stenosis assessment may prove useful in predicting burner risk, especially in athletes with extension-compression injuries.

Clinical, Functional, and Radiographic Assessments of the Conventional and Modified Boyd-Anderson Surgical Procedures for Repair of Distal Biceps Tendon Ruptures

The purpose of this study was to evaluate the clinical, functional, and radiographic outcomes of the conventional and modified Boyd-Anderson procedures for repair of distal biceps tendon ruptures. Thirteen of 18 men who underwent surgical repair for unilateral distal biceps tendon ruptures at one university center participated in the study. In general, follow-up outcomes were favorable with respect to return to premorbid activity levels, patient satisfaction with surgical outcome, and overall clinical results. Elbow flexion, forearm supination, and upper extremity functional concentric peak torque and range of motion results were not significantly different between the surgical and nonsurgical arms when dominance was controlled as a confounding factor. Radiographic findings revealed no clinically remarkable signs of heterotopic ossification or proximal radioulnar synostosis. Results of the study reveal that the conventional and modified Boyd-Anderson procedures are clinically, functionally, and radio-graphically efficacious for repair of distal biceps tendon ruptures.

Reliability and validity of three quality rating instruments for systematic reviews of observational studies

To assess the inter-rater reliability, validity, and inter-instrument agreement of the three quality rating instruments for observational studies. Inter-rater reliability, criterion validity, and inter-instrument reliability were assessed for three quality rating scales, the Downs and Black (D&B), Newcastle-Ottawa (NOS), and Scottish Intercollegiate Guidelines Network (SIGN), using a sample of 23 observational studies of musculoskeletal health outcomes. Inter-rater reliability for the D&B (Intraclass correlations [ICC] = 0.73; CI = 0.47-0.88) and NOS (ICC = 0.52; CI = 0.14-0.76) were moderate to good and was poor for the SIGN (κ = 0.09; CI = -0.22-0.40). The NOS was not statistically valid (p = 0.35), although the SIGN was statistically valid (p < 0.05) with medium to large effect sizes (f(2) = 0.29-0.47). Inter-instrument agreement estimates were κ = 0.34, CI = 0.05-0.62 (D&B versus SIGN), κ = 0.26, CI = 0.00-0.52 (SIGN versus NOS), and κ = 0.43, CI = 0.09-0.78 (D&B versus NOS). Reliability and validity are quite variable across quality rating scales used in assessing observational studies in systematic reviews. Copyright

Body size and walking cadence affect lower extremity joint power in children's gait

Obese children move less and with greater difficulty than normal-weight counterparts but expend comparable energy. Increased metabolic costs have been attributed to poor biomechanics but few studies have investigated the influence of obesity on mechanical demands of gait. This study sought to assess three-dimensional lower extremity joint powers in two walking cadences in 28 obese and normal-weight children. 3D-motion analysis was conducted for five trials of barefoot walking at self-selected and 30% greater than self-selected cadences. Mechanical power was calculated at the hip, knee, and ankle in sagittal, frontal and transverse planes. Significant group differences were seen for all power phases in the sagittal plane, hip and knee power at weight acceptance and hip power at propulsion in the frontal plane, and knee power during mid-stance in the transverse plane. After adjusting for body weight, group differences existed in hip and knee power phases at weight acceptance in sagittal and frontal planes, respectively. Differences in cadence existed for all hip joint powers in the sagittal plane and frontal plane hip power at propulsion. Frontal plane knee power at weight acceptance and sagittal plane knee power at propulsion were significantly different between cadences. Larger joint powers in obese children contribute to difficulty performing locomotor tasks, potentially decreasing motivation to exercise.

Effectiveness of prophylactic ankle stabilisers for prevention of ankle injuries

SummaryAnkle injuries are common at many levels of athletic participation. A relatively recent approach in injury intervention is the use of prophylactic ankle stabilisers (PAS). PAS are used with the intention of reducing the frequency and severity of ankle injuries in a cost-effective manner. To date, 4 studies have been completed to determine the clinical efficacy of PAS. Although all of the studies have methodological limitations, a general consensus of agreement exists among the findings: PAS are effective in reducing the incidence of acute ankle sprains. However, the effect of PAS on ankle sprain severity remains unclear, as varying results have been reported. PAS do not increase the risk of knee injuries. The use of PAS for ankle injury reduction appears to be justified although further research is required.

Gender comparisons of dynamic restraint and motor skill in children.

Objectives:To assess differences in neuromuscular dynamic restraint between high-skilled and low-skilled prepubescent girls and boys. To determine the contribution of sport experience and physical characteristics to motor skill. Subjects:Nineteen girls and 17 boys (8.89-9.40 y) participated. Intervention:Isometric hamstring and quadriceps muscle strength was assessed. Subjects performed 3 landing trials for measurement of preparatory EMG and vertical leg stiffness. Motor skill was assessed through analysis of 12 fundamental tasks. Sport experience was reported as hours per week and total years in organized and nonorganized activity. Outcome Measures:Dynamic restraint variables of isometric strength, preparatory EMG activity, and vertical leg stiffness were measured between groups. The contributions of time in sport, type of sport, and physical characteristics on skill were analyzed. Results:No significant gender or skill differences were found in quadriceps strength (P = 0.73), hamstring strength (P = 0.96), hamstring-to-quadriceps ratio (P = 0.71), or vertical leg stiffness (P = 0.38). Low-skilled children exhibited significantly greater (47.8%) preparatory hamstring-quadriceps coactivation than high-skilled subjects (P = 0.03). Participation in organized and nonorganized sport accounted for 29% of the variance in motor skill. Conclusions:Neuromuscular differences between genders were not observed, but dynamic restraint EMG measures differed between skill levels. The factors predisposing females to noncontact injuries may develop prepuberty to postpuberty from a combination of variables. Greater coactivation in the low-skilled group appears consistent with immature feedforward neuromuscular control strategies. These unrefined motor skills are less economical, may compromise dynamic restraint, and appear partially determined by sport experience.