Yamauchi Koun, Yoshiko Akito, Suzuki Shigetoshi, Kato Chisato, Akima Hiroshi, Kato Takayuki, Ishida Koji
1 Department of Orthopedic Surgery, Akita Hospital, Chiryu, Japan.
2 Graduate School of Medicine, Nagoya University, Nagoya, Japan.
J Orthop Surg (Hong Kong). 2017 Sep-Dec;25(3):2309499017739765. doi: 10.1177/2309499017739765.
We aimed to longitudinally investigate individual thigh muscle changes using magnetic resonance imaging (MRI) during treatment with cast of ankle or foot fracture. Moreover, we aimed to demonstrate whether measurements of muscle cross-sectional area (CSA) are sensitive to muscle changes, contributing to simpler methods in clinical application .
Ten patients undergoing treatment with cast of acute ankle or foot fractures were studied. Axial MRI (1.5 T) was conducted around the affected mid-thigh region after the injury (Pre), after maintaining a nonweight-bearing (NWB) period (approximately 28 days), and after finishing rehabilitation (recovery). Regarding individual thigh muscles, the total CSAs corresponding to 40% of the femoral length (FL) and the CSAs at 5% interval of the FL were longitudinally measured. Standardized response means (SRMs) were accessed for sensitivity in the muscle changes.
The total CSAs at NWB were significantly lower than those at Pre in vastus lateralis (10.9% ± 5.4%), vastus intermedius (8.4% ± 6.7%), and vastus medialis (11.2% ± 6.9%) ( p < 0.01 for all). In contrast, at recovery, the only significant muscle atrophy relative to that at Pre was observed in the semitendinosus of the proximal 15% and 10% CSAs ( p < 0.01 and p = 0.01, respectively). In all muscles, SRM using a single-slice CSA at or near the muscle belly was high.
Thigh muscle changes differ according to the variations in individual muscles. CSA measurements at or near the muscle belly are simple methods and sensitive indicators of these muscle changes.
我们旨在利用磁共振成像（MRI）纵向研究踝关节或足部骨折石膏固定治疗期间大腿各肌肉的变化。此外，我们旨在证明肌肉横截面积（CSA）测量对肌肉变化是否敏感，从而有助于在临床应用中采用更简便的方法。
对10例接受急性踝关节或足部骨折石膏固定治疗的患者进行研究。在受伤后（术前）、保持非负重（NWB）期（约28天）后以及康复结束（恢复）后，对患侧大腿中部区域进行轴向MRI（1.5T）检查。对于大腿各肌肉，纵向测量对应于股骨长度（FL）40%的总CSA以及FL每隔5%处的CSA。获取标准化反应均值（SRM）以评估肌肉变化的敏感性。
在NWB期，股外侧肌（10.9%±5.4%）、股中间肌（8.4%±6.7%）和股内侧肌（11.2%±6.9%）的总CSA显著低于术前（所有p<0.01）。相比之下，在恢复时，相对于术前，仅在CSA近端15%和10%的半腱肌中观察到显著的肌肉萎缩（分别为p<0.01和p=0.01）。在所有肌肉中，使用肌腹处或其附近单一层面CSA的SRM较高。
大腿肌肉变化因个体肌肉差异而异。在肌腹处或其附近进行CSA测量是简单的方法，也是这些肌肉变化的敏感指标。
