METHODS: This cross-sectional study enrolled 202 outpatients with KOA from 8 Japanese orthopedic clinics and measured knee extensor/flexor muscle strength (MS) and knee extension/flexion range of motion (ROM). We used multiple regression analysis to evaluate the sources of variation, including sex, age, body mass index, Kellgren-Lawrence (K-L) classification, bilateral KOA, and exercise habits. Magnitude of between-subgroup differences is expressed as standard deviation ratio (SDR) based on a three-level nested analysis of variance, with SDR ≥ 0.4 as the threshold for requiring RIs specific for subgroups. RIs were calculated parametrically using two-parameter Box-Cox formula if Gaussian transformation of RVs was successful, otherwise calculated nonparametrically.
RESULTS: Partitioning was required by sex for extensor and flexor MS (SDR = 0.65, 0.57, respectively) and by K-L classification for flexion ROM (SDR = 0.54). RIs were determined parametrically for extensor MS as 0.27-2.09 (male) and 0.27-1.54 (female) Nm/kg and for flexor MS 0.18-1.20 (male) and 0.13-0.79 (female) Nm/kg. On the other hand, RIs for extension and flexion ROM were determined nonparametrically due to discrete nature of their RVs. The RIs determined for extension ROM were -15°-0° and for flexion ROM were 105°-150° (for K-L grade I/II) and 95°-140° (for K-L grade III/IV).
CONCLUSIONS: The ranges of RIs determined specifically for patients with mild to moderate KOA were in-between those of age-matched healthy controls and pre-surgical KOA patients, both of which we had reported for use in physiotherapeutic management of KOA patients undergone total knee arthroplasty. The newly derived RIs will provide an objective benchmark for physiotherapy targeting outpatients with mild to moderate KOA.
方法:这项横断面研究纳入了来自8个日本骨科诊所的202名KOA门诊患者,并测量了膝关节伸肌/屈肌力量(MS)和膝关节伸肌/屈肌活动范围(ROM)。我们使用多元回归分析来评估变异的来源,包括性,年龄,身体质量指数,Kellgren-Lawrence(K-L)分类法,双边KOA,锻炼习惯。亚组之间差异的幅度表示为基于三级嵌套方差分析的标准偏差比(SDR)。以SDR≥0.4作为要求特定于亚组的RI的阈值。如果RV的高斯变换成功,则使用两参数Box-Cox公式参数计算RI,否则非参数计算。
结果:对于伸肌和屈肌MS(分别为SDR=0.65、0.57),对于屈肌ROM(SDR=0.54),需要按性别进行分区。伸肌MS的RI参数为0.27-2.09(男性)和0.27-1.54(女性)Nm/kg,屈肌MS的RI参数为0.18-1.20(男性)和0.13-0.79(女性)Nm/kg。另一方面,由于RV的离散性质,非参数确定了伸展和屈曲ROM的RI。对于伸展ROM确定的RI为-15°-0°,对于屈曲ROM确定的RI为105°-150°(对于K-L等级I/II)和95°-140°(对于K-L等级III/IV)。
结论:为轻度至中度KOA患者专门确定的RI范围介于年龄匹配的健康对照组和手术前KOA患者之间,我们已经报道了这两种方法用于全膝关节置换术后KOA患者的理疗管理.新得出的RI将为针对轻度至中度KOA的门诊患者的物理治疗提供客观基准。