A.H. Alnahdi, PT, PhD, Rehabilitation Sciences Department, College of Applied Medical Sciences, King Saud University, PO Box 10219, Riyadh 11433, Saudi Arabia.
J.A. Zeni, PT, PhD, Department of Physical Therapy, University of Delaware, Newark, Delaware.
Phys Ther. 2014 Aug;94(8):1154-62. doi: 10.2522/ptj.20130335. Epub 2014 Mar 20.
Because people with total knee arthroplasty (TKA) have persistent functional limitations and disability, identifying modifiable risk factors for persistent disability is warranted. Before surgery, people have pervasive lower extremity muscle weakness. The fact that hip abductor muscle strength is often not targeted in postoperative rehabilitation may contribute to functional limitations.
Study objectives were: (1) to examine the reliability of handheld dynamometry (HHD) for measuring hip abductor strength and (2) to determine whether hip abductor strength contributes to physical function beyond the contribution of quadriceps muscle strength.
This was a cross-sectional study.
Two-hundred ten participants underwent quadriceps and hip abductor muscle strength testing and measurement of physical function (performance-based and self-reported outcomes). Correlation and regression equations were built to determine the relationships of strength, pain, and functional ability. A subset of 16 participants underwent hip abductor strength testing at 2 sessions to determine the reliability of the measure.
Measuring hip abductor strength with HHD yielded excellent relative reliability, with an intraclass correlation coefficient (ICC [2,3]) of .95 and a 95% confidence interval of .86 to .98, but moderate absolute reliability, with a minimal detectable change (with 95% confidence) of 47.6 N and a 95% confidence interval of 35.5 to 76.5. Hip abductor strength made a significant additional contribution to performance-based measures of physical function after anthropometric covariates and quadriceps muscle strength were accounted for. Hip abductor strength did not show bivariate correlations with patient-reported measures of physical function and did not contribute to patient-reported physical function after covariates and quadriceps muscle strength were accounted for.
A cause-and-effect relationship between hip abductor strength and physical function could not be established.
In people with unilateral TKA, HHD testing of hip abductor strength is reliable. Hip abductor strength contributes to performance-based but not patient-reported measures of physical function in people with unilateral TKA.
由于全膝关节置换术（TKA）患者存在持续的功能受限和残疾，因此有必要确定可改变的持续性残疾的风险因素。术前，患者存在广泛的下肢肌肉无力。髋关节外展肌力量在术后康复中通常未被针对性治疗，这可能导致功能受限。
本研究的目的是：（1）检验手持测力计（HHD）测量髋关节外展肌力量的可靠性；（2）确定髋关节外展肌力量是否除了股四头肌力量以外，对身体功能有贡献。
这是一项横断面研究。
210 名参与者接受了股四头肌和髋关节外展肌力量测试以及身体功能（基于表现和自我报告的结果）的测量。建立相关和回归方程以确定力量、疼痛和功能能力之间的关系。一组 16 名参与者在 2 次就诊时接受了髋关节外展肌力量测试，以确定该测量的可靠性。
使用 HHD 测量髋关节外展肌力量具有极好的相对可靠性，组内相关系数（ICC [2,3]）为.95，95%置信区间为.86 至.98，而绝对可靠性为中等，最小可检测变化（95%置信区间）为 47.6N，95%置信区间为 35.5 至 76.5。在考虑了人体测量学协变量和股四头肌力量后，髋关节外展肌力量对基于表现的身体功能测量有显著的额外贡献。髋关节外展肌力量与患者报告的身体功能测量无双变量相关性，在考虑了协变量和股四头肌力量后，髋关节外展肌力量对患者报告的身体功能没有贡献。
不能建立髋关节外展肌力量与身体功能之间的因果关系。
在单侧 TKA 患者中，使用 HHD 测试髋关节外展肌力量是可靠的。在单侧 TKA 患者中，髋关节外展肌力量对基于表现的但不是患者报告的身体功能测量有贡献。
