Lee Cassandra, Ma Jianjun, Deal D Nicole, Smith Beth P, Koman L Andrew, Smith Thomas L, Shilt Jeffrey S
Department of Orthopaedic Surgery, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, NC 27157, USA.
J Pediatr Orthop. 2006 Sep-Oct;26(5):628-33. doi: 10.1097/01.bpo.0000226283.39319.06.
The muscle and nerve responses to stresses applied during distraction osteogenesis have not been clearly defined. This study hypothesized that distraction resulting in 30% lengthening decreases muscle force generation of the lengthened muscle and increasing the frequency of distraction attenuates the decrease of force generation accompanying lengthening. This study investigated the effects of different distraction frequencies on neuromuscular recovery in a rabbit model. Animals were assigned into group 1 (low-frequency distraction) and group 2 (high-frequency distraction). Distraction was continued until a 30% increase in the original tibial length was achieved. After consolidation of the osteotomy, knee and ankle range of motion, muscle force generation, and neuromuscular junction parameters were evaluated. Lengthening of 30% resulted in significantly decreased range of motion compared with the control leg (P < 0.05). Lengthening of 30% also substantially decreased force generation of the peroneus longus muscle. However, force generation of the peroneus longus muscle in the high-frequency group was 70.5% +/- 6.5% of the control side, significantly higher than that in the low-frequency distraction group (49.7% +/- 4.8% of the control side, P < 0.05). There was no statistical difference between the 2 groups in neuromuscular junction morphology, although an abnormal shape of the postsynaptic neuromuscular junction was observed after distraction. The use of a high-frequency distraction technique during limb lengthening may result in a reduction in impairment of knee and ankle range of motion and improved muscle function compared with that observed with the use of low-frequency distraction. Repeated microtrauma to the soft tissues associated with high-frequency distraction may facilitate the regenerative capacity of the soft tissues and result in an improved outcome of muscle and nerve function.
在牵张成骨过程中施加应力时，肌肉和神经的反应尚未明确界定。本研究假设，导致30%延长的牵张会降低延长肌肉的肌力产生，并且增加牵张频率可减弱延长伴随的肌力产生下降。本研究在兔模型中探究了不同牵张频率对神经肌肉恢复的影响。动物被分为第1组（低频牵张）和第2组（高频牵张）。持续牵张直至胫骨原始长度增加30%。截骨愈合后，评估膝关节和踝关节活动范围、肌力产生以及神经肌肉接头参数。与对照侧相比，30%的延长导致活动范围显著减小（P < 0.05）。30%的延长也显著降低了腓骨长肌的肌力产生。然而，高频组腓骨长肌的肌力产生为对照侧的70.5%±6.5%，显著高于低频牵张组（对照侧的49.7%±4.8%，P < 0.05）。尽管牵张后观察到突触后神经肌肉接头形状异常，但两组在神经肌肉接头形态上无统计学差异。与低频牵张相比，在肢体延长过程中使用高频牵张技术可能会减少膝关节和踝关节活动范围的损伤，并改善肌肉功能。与高频牵张相关的软组织反复微创伤可能促进软组织的再生能力，并导致肌肉和神经功能的改善结果。
