ACL重建术后后侧与中立标准化单腿下蹲测试中的股四头肌力量相关性及生物力学差异
简介
本研究纳入66例ACL重建术后5-7个月的运动员，比较单腿下蹲测试（SLST）中非支撑腿置于后方（PS）与中立位（NS）两种标准化姿势对测试结果的影响。关键发现：PS组SLST时患侧膝最大屈曲对称指数（LSI）与股四头肌力量LSI呈中度相关（R=0.37），而NS组仅呈弱相关（R=0.27）。两组患侧膝屈曲角度和膝力矩贡献均显著低于健侧，而髋关节力矩贡献显著…
英文摘要
BACKGROUND: After anterior cruciate ligament reconstruction (ACLR), the single-leg squat test (SLST) may be included in an initial/baseline performance testing battery. During the SLST, the position of the nonstance limb is known to affect the biomechanics/kinematics of the test, making SLST standardization important for comparing outcomes after ACLR. HYPOTHESIS: The position of the nonstance limb during the SLST will influence the correlation between peak knee flexion limb-symmetry index (LSI) and quadriceps strength LSI, and affect lower extremity biomechanics during the SLST. STUDY DESIGN: Biomechanical cohort study. LEVEL OF EVIDENCE: Level 3. METHODS: A total of 66 athletes completed quadriceps strength and single-leg squat testing 5 to 7 months after ACLR. Based on their nonstance limb position during the SLST, athletes were placed in either a posterior standardization (PS) or neutral standardization (NS) group for biomechanical analyses. Correlations between peak knee flexion LSI during the SLST and quadriceps strength LSI were investigated, and between- and within-group analyses of lower extremity joint biomechanics were completed. RESULTS: Performing the SLST with PS produced a medium correlation between peak knee flexion LSI and quadriceps strength LSI (R = 0.37, R2 = 0.14), whereas NS produced a small correlation (R = 0.27, R2 = 0.07). In both groups, the surgical limb showed significantly less peak knee flexion (PS; P = 0.02) (NS; P = 0.03) and knee moment-contribution (PS; P = 0.04) (NS; P = 0.0001), as well as significantly more hip moment-contribution (PS; P = 0.03) (NS; P = 0.0001). Surgical limb change in anterior center of pressure was significantly greater with NS relative to PS (P = 0.03), and nonsurgical limb ankle moment-contribution was significantly greater with PS relative to NS (P = 0.02). CONCLUSION: Although surgical limb knee moment contribution is reduced significantly in both groups after ACLR, peak knee flexion LSI may be a better indicator of quadriceps strength LSI during the SLST with PS than with NS. CLINICAL RELEVANCE: After ACLR, single-leg squatting with PS may be preferred for knee-specific performance testing and as an exercise regression for horizontal hopping, whereas NS may be preferred as an exercise regression for vertical hopping. Strength-of-Recommendation Taxonomy (SORT): B-level recommendation (biomechanical, Level 3 cohort study).