Clinicians frequently assess asymmetry in strength, flexibility, and performance characteristics as a method of screening for potential musculoskeletal injury. The identification of asymmetry in countermovement jumps may be an ideal method to reveal asymmetry in other lower extremity characteristics such as strength that otherwise may require additional testing, potentially reducing the time and burden on both the athlete and clinicians. The present study aims to examine the ability of asymmetry in both the single-leg and two-leg countermovement jump tests to accurately detect hip abduction, hip adduction, and eccentric hamstring strength asymmetry. Fifty-eight young male elite soccer players from the same professional academy performed a full battery of functional performance tests which included an assessment of hip adductor and abductor strength profiles, eccentric hamstring strength profiles, and neuromuscular performance and asymmetries during countermovement jumps. Bilateral variables attained from both the single-leg and two-leg countermovement jump tests included concentric impulse (Ns), eccentric mean force (N), and concentric mean force (N) computed by the VALD ForceDecks software. Average maximal force (N) was calculated bilaterally for the strength assessments. Asymmetry was calculated for each variable using 100 × |(right leg − left leg)/(right leg)| and grouped into three categories: 0 to <10%, 10% to <20%, and 20% or greater. Analyses were performed for the two higher asymmetry groups. The accuracy to detect strength asymmetry was assessed as the sensitivity, specificity, and predictive values for positive and negative tests. The outcomes from the accuracy assessments suggest that the single-leg countermovement jump concentric impulse variable at the 20% threshold is indicative of a youth male soccer player having hip adduction strength asymmetry while also demonstrating more accuracy and applicability than the two-leg countermovement jump concentric impulse variable.

The vertical jump (VJ) is one of the most important movements for basketball athletes and therefore determining modifiable predictors of the VJ would aid substantially in crafting more effective training regimens. The purpose of this study was to determine if isokinetic quadriceps strength and torque predict VJ height and which characteristics and testing speed is the strongest predictor of VJ height. Fifteen subjects (age: 18.5 ± 1.0 years, height: 195.9 ± 6.9 cm, weight: 96.2 ± 13.7 kg) from a single Division I men’s basketball team were recruited for this study. All participants performed a standing vertical jump with arm-swing to assess their maximum VJ height. Participants also completed an isokinetic knee extension strength protocol that included testing at multiple speeds. Pearson and Spearman tests found no significant correlation between jump height and peak torque at any of the speeds. Regression analysis showed a statistically significant relationship between time to peak torque at 300°/s and VJ height (R² = 0.23, p = 0.04). These findings suggest that in a population of elite basketball players, the knee’s ability to rapidly generate torque likely plays a greater role in VJ performance than its ability to generate high magnitude of torque. This presents a potential benefit of explosive training regimens such as plyometrics for maximization of jump performance.

To synthesize existing literature regarding the indications and outcomes of femoral rotational osteotomies (FDO) for femoroacetabular impingement (FAI) due to. Medline, Cochrane, and Embase were searched using keywords "femoroacetabular impingement", "rotational osteotomy" and others to identify FAI patients undergoing FDO. Double-screened studies were reviewed by blinded authors according to inclusion criteria. Data from full texts was extracted including study type, number of patients, sex, mean age, surgical indication, type of dysplasia, associated pathology, surgical technique, follow-up, and pre-op/post-op evaluations of the following: impingement test, femoral version (FV), 'other angles measured', outcome scores, range of motion (ROM). 7 studies including 91 patients (97 FDO surgeries), 73 females (80 %) with mean age of 28.3 years, and follow-up mean of 2.44 ± 2.83 years. Pain or impingement was the most common clinical indication, while others included aberrant FV and ROM measurements for both anteverted and retroverted femurs. There were reports of FDO being performed with concomitant procedures addressing other pathology. Various outcome scores and ROM measurements showed postoperative improvement after FDO. Complication data was sparse, preventing aggregation. The rate of unplanned reoperation was 40 % (where reported), with 'hardware removal' being the most common. FDO is effective in treating FAI due to increased FV, improving clinical symptoms, and potentially delaying articular degeneration. Hardware removal surgery remains an inherent risk in undergoing FDO. Further work is needed to discover indications warranting FDO as a primary treatment versus hip arthroscopy. This review contains 4 studies with Level IV evidence and 3 studies with Level III evidence.

A lateral jump assessment may provide unique benefits in sports such as basketball that require multidirectional performance optimization. This study aimed to examine selected force-plate derived metrics as predictors of lateral jump task distance in men’s basketball players. Twenty-two NCAA Division-I men’s basketball players (19.4 ± 1.3 years, 95.0 ± 12.5 kg, 196.5 ± 8.1 cm) each performed six single leg lateral jumps while standing on a force plate (1200 Hz, Kistler Instrument Corp). The lateral jump task involved the subject beginning by standing on the force plate and jumping sideways off one foot and then landing on the floor with the opposite foot. Three-dimensional ground reaction force curves were used to identify the eccentric and concentric phases of the jump and variables were computed each from the lateral (y), vertical (z), and resultant (r) force traces. Peak ground reaction force (pGRF), ground reaction force angle (θ_r), eccentric braking rate of force development (ECC-RFD), average concentric force (CON-AVG), total jump duration, eccentric phase duration, and eccentric to total time ratio were evaluated for predictive ability. Three regression models were able to significantly (p<0.05) predict jump distance: (1) pGRF_y, pGRF_z, and θ_r (p<0.001, R² = 0.273), (2) Relative pGRF_y, Relative pGRF_z, and θ_r ((p<0.001, R² = 0.214), and (3) Relative CON-AVG_y and Relative pGRF_r (p<0.001, R² = 0.552). While several force plate-derived metrics were identified as significant predictors, a model with Relative CON-AVG_y and Relative pGRF_r explained a greater variability in performance (R² = 0.55) compared to the other variables which were low, yet also significant. These results suggest that lateral ground reaction forces can be used to evaluate lateral jump performance with the use of three-dimensional force plates. The identified predictors can be used as a starting point for performance monitoring, as basketball training interventions can be directed at specific improvements in the identified metrics.