Malaiya Ritu, McNee Anne E, Fry Nicola R, Eve Linda C, Gough Martin, Shortland Adam P
One Small Step Gait Laboratory, Guy's Hospital, London SE1 9RT, UK.
J Electromyogr Kinesiol. 2007 Dec;17(6):657-63. doi: 10.1016/j.jelekin.2007.02.009. Epub 2007 Apr 24.
We collected 3D ultrasound images of the medial gastrocnemius muscle belly (MG) in 16 children with spastic hemiplegic cerebral palsy (SHCP) (mean age: 7.8 years; range: 4-12) and 15 typically-developing (TD) children (mean age: 9.5 years; range: 4-13). All children with SHCP had limited passive dorsiflexion range on the affected side with the knee extended (mean+/-1SD: -9.3 degrees +/-11.8). Scans were taken of both legs with the ankle joint at its resting angle (RA) and at maximum passive dorsiflexion (MD), with the knee extended. RA and MD were more plantar flexed (p<0.05) in children with SHCP than in TD children. We measured the volumes and lengths of the MG bellies. We also measured the length of muscle fascicles in the mid-portion of the muscle belly and the angle that the fascicles made with the deep aponeurosis of the muscle. Volumes were normalised to the subject's body mass; muscle lengths and fascicle lengths were normalised to the length of the fibula. Normalised MG belly lengths in the paretic limb were shorter than the non-paretic side at MD (p=0.0001) and RA (p=0.0236). Normalised muscle lengths of the paretic limb were shorter than those in TD children at both angles (p=0.0004; p=0.0003). However, normalised fascicle lengths in the non-paretic and paretic limbs were similar to those measured in TD children (p>0.05). When compared to the non-paretic limb, muscle volume was reduced in the paretic limb (p<0.0001), by an average of 28%, and normalised muscle volume in the paretic limb was smaller than in the TD group (p<0.0001). The MG is short and small in the paretic limb of children with SHCP. The altered morphology is not due to a decrease in fascicle length. We suggest that MG deformity in SHCP is caused by lack of cross-sectional growth.
我们收集了16例痉挛性偏瘫型脑瘫（SHCP）儿童（平均年龄：7.8岁；范围：4 - 12岁）和15例发育正常（TD）儿童（平均年龄：9.5岁；范围：4 - 13岁）的腓肠肌内侧肌腹（MG）的三维超声图像。所有SHCP儿童患侧在膝关节伸展时被动背屈范围受限（平均±1标准差：-9.3度±11.8）。在踝关节处于静息角度（RA）和最大被动背屈（MD）且膝关节伸展的情况下，对双腿进行扫描。与TD儿童相比，SHCP儿童的RA和MD更偏向跖屈（p<0.05）。我们测量了MG肌腹的体积和长度。我们还测量了肌腹中段的肌束长度以及肌束与肌肉深腱膜形成的角度。体积根据受试者体重进行归一化；肌肉长度和肌束长度根据腓骨长度进行归一化。在MD（p = 0.0001）和RA（p = 0.0236）时，患侧肢体的归一化MG肌腹长度短于非患侧。在两个角度下患侧肢体的归一化肌肉长度均短于TD儿童（p = 0.0004；p = 0.0003）。然而，非患侧和患侧肢体的归一化肌束长度与TD儿童测量值相似（p>0.05）。与非患侧肢体相比，患侧肢体的肌肉体积减小（p<0.0001），平均减少28%，患侧肢体的归一化肌肉体积小于TD组（p<0.0001）。SHCP儿童患侧肢体的MG短且小。形态改变并非由于肌束长度减少所致。我们认为SHCP中MG畸形是由横断面生长不足引起的。
