Ankle dorsiflexion range of motion and hip abductor strength can predict Lower Quarter Y-Balance Test performance in healthy males.

OBJECTIVES: The aim of the study was to assess whether strength and range of motion (ROM) of the hip and ankle are the factors determining performance in the Lower Quarter Y-Balance test (YBT-LQ). DESIGN: Cross-sectional study. PARTICIPANTS: 66 healthy males (age: 25.2±6.8 years) participated in this study. MAIN OUTCOME MEASURES: Participants underwent assessments of ankle dorsiflexion (DF) ROM, hip internal rotation (IR) ROM, external rotation (ER) ROM and isometric strength of hip abductor (ABD), extensor (EXT) and external rotators (ERS) muscles together with YBT-LQ for both legs. A forward 2-steps multiple linear regression analysis was conducted to examine the relationship between the predictor variables and the criterion variable. RESULTS: Ankle DF ROM predicted anterior (ANT) reach (R2 = 0.49; R2 = 0.33; p < 0.001). The model with hip ABD strength and ankle DF ROM explained posteromedial (PM) reach variance for stance leg (R2 = 0.35; p < 0.001), while only hip ABD strength was included for kicking leg (R2 = 0.19; p = 0.007). The model with ankle DF ROM and hip ABD strength explained posterolateral (PL) reach for stance leg (R2 = 0.41; p < 0.001). Hip ABD was the only predictor for kicking leg PL reach (R2 = 0.15; p < 0.001). YBT-LQ composite score was explained by ankle DF ROM and hip ABD strength for both legs (R2 = 0.44; p < 0.001) and (R2 = 0.25; p = 0.002). CONCLUSION: Hip ABD strength and ankle DF ROM can determine performance in the YBT-LQ. Strength of hip EXT, ERS as well as ROM of hip IR and ER did not predict YBT-LQ performance.

The Effects of Gluteal Strength and Activation on the Relationship Between Femoral Alignment and Functional Valgus Collapse During a Single-Leg Landing.

CONTEXT: A bias toward femoral internal rotation is a potential precursor to functional valgus collapse. The gluteal muscles may play a critical role in mitigating these effects. OBJECTIVE: Determine the extent to which gluteal strength and activation mediate associations between femoral alignment measures and functional valgus collapse. DESIGN: Cross-sectional. SETTING: Research laboratory. PATIENTS OR OTHER PARTICIPANTS: Forty-five females (age = 20.1 [1.7] y; height = 165.2 [7.6] cm; weight = 68.6 [13.1] kg) and 45 males (age = 20.8 [2.0] y; height = 177.5 [8.7] cm; weight = 82.7 [16.5] kg), healthy for 6 months prior. INTERVENTION(S): Femoral alignment was measured prone. Hip-extension and abduction strength were obtained using a handheld dynamometer. Three-dimensional biomechanics and surface electromyography were obtained during single-leg forward landings. MAIN OUTCOME MEASURES: Forward stepwise multiple linear regressions determined the influence of femoral alignment on functional valgus collapse and the mediating effects of gluteus maximus and medius strength and activation. RESULTS: In females, less hip abduction strength predicted greater peak hip adduction angle (R2 change = .10; P = .02), and greater hip-extensor activation predicted greater peak knee internal rotation angle (R2 change = .14; P = .01). In males, lesser hip abduction strength predicted smaller peak knee abduction moment (R2 change = .11; P = .03), and the combination of lesser hip abduction peak torque and lesser gluteus medius activation predicted greater hip internal rotation angle (R2 change = .15; P = .04). No meaningful mediation effects were observed (υadj < .01). CONCLUSIONS: In females, after accounting for femoral alignment, less gluteal strength and higher muscle activation were marginally associated with valgus movement. In males, less gluteal strength was associated with a more varus posture. Gluteal strength did not mediate femoral alignment. Future research should determine the capability of females to use their strength efficiently.

NO DIFFERENCES IN HIP RANGE OF MOTION EXISTS BETWEEN BASEBALL PLAYERS WITH AN ULNAR COLLATERAL LIGAMENT TEAR AND HEALTHY BASEBALL PLAYERS.

BACKGROUND AND PURPOSE: Restrictions in hip rotational motion of the baseball athlete can alter throwing mechanics in a manner that is inefficient and increases risk of injury. The purpose of this study was to assess for differences in hip external rotation (ER) and internal rotation (IR) range of motion (ROM) between baseball players with an ulnar collateral ligament (UCL) tear and healthy baseball players. DESIGN: Case-control. METHODS: Eighty-seven baseball players with a UCL tear (UCL) were compared with 87 age, experience, and position-matched healthy baseball players (CONT). UCL were enrolled at the initial visit to the outpatient sports medicine facility while CONT were measured before their baseball season. Passive hip ROM (ER and IR) of the stance and lead limbs was measured in the prone position using a bubble goniometer. Hip total range of motion (TRM) was calculated by adding ER and IR of each limb. Independent t-tests were run to compare mean group differences for hip ROM (p<0.05). RESULTS: No differences between groups were discovered for hip ER on the stance (UCL = 33.9 °±9.9 °, CONT = 34.3 °±10.6 °, p = 0.8) or lead (UCL = 32.9 °±9.9 °, CONT = 34.4 °±10.0 °, p = 0.3) limbs. Similarly, there were no group differences in hip IR on the stance (UCL = 30.6 °±10.5 °, CONT = 29.6 °±9.5 °, p = 0.5) or lead (UCL = 33.5 °±17.5 °, CONT = 29.5 °±9.0 °, p = 0.1) limbs. The groups were also similar in hip TRM on the stance (UCL = 64.5 °±13.7 °, CONT = 64.0 °±17.2 °, p = 0.8) and lead (UCL = 66.4 °±17.4 °, CONT = 63.9 °±15.6 °, p = 0.3) limbs. CONCLUSIONS: When measured in the prone position, hip passive ROM is not different between baseball players with a UCL tear compared to a matched healthy cohort. LEVEL OF EVIDENCE: Level 3.

The Role of Decreased Hip IR as a Cause of Low Back Pain in a Golfer: a Case Report.

BACKGROUND: Among golf injuries, low back pain (LBP) is the most common compliant for both professional and amateur golfers. Hip rotational range of motion (ROM) might be related to LBP in those who repeatedly place specific activity rotational demands on the hip in one direction. Coordination of timing of movement (neural control) between the hip and lumbopelvic region during trunk movements is critical for normal mechanics. Altered timing can contribute to areas of high tissue loading and can lead to LBP symptoms seen during active lower limb movement tests. Patient was a 42-year-old male recreational golfer who presented with low back pain and decreased hip internal rotation ROM. METHODS: With the use of manual physical therapy to increase hip ROM and lumbar stabilization therapeutic exercises, the patient was able to return to pain-free golf and to better his handicap by three strokes. RESULTS: Significant improvement was seen in his Oswestry outcome score, and a (-) prone instability test was noted. CONCLUSION: It is recommended to address hip ROM limitations in those experiencing low back pain while golfing. Rapid spinal rotation may produce large spinal loads, but this is likely not the major contributor to low back pain in golfers. Mechanical factors may play a larger role.