Abstract：
OBJECTIVE: Some patients with Hirayama disease (HD) may have generalized joint hypermobility (GJH), which may excessively increase cervical range of motion (ROM) and then worsen the HD. The purpose of this study was to identify the frequency of GJH in HD patients and to analyze the effect of GJH on cervical ROM and the severity of HD.
METHODS: The Beighton scoring system (≥4) was used to diagnose GJH in 84 HD patients. All patients underwent assessments of cervical-flexion/extension ROM; motor unit number estimation in bilateral abductor pollicis brevis (APB) muscles; handgrip strength; and the disabilities of the arm, shoulder, and hand assessments.
RESULTS: Concomitant GJH was identified in 20 (23.8%) HD patients. The HD patients with GJH exhibited greater cervical-flexion (P < .001) and cervical-extension (P = .033) ROM than those without GJH. Both greater single motor unit potential amplitudes (symptomatic side: P = .005; less-symptomatic side: P = .011) and lower motor unit numbers (symptomatic side: P = .008; less-symptomatic side: P = .013) in bilateral APB, along with lower compound muscle action potential amplitudes on the symptomatic-side APB (P = .039), were observed in patients with GJH than those without GJH. There was a mild negative correlation between motor unit number and cervical-flexion ROM in HD patients (symptomatic side: r = -0.239, P = .028; less-symptomatic side: r = -0.242, P = .027).
CONCLUSIONS: The frequency of GJH in HD patients may be higher than in the general population. Importantly, GJH may exacerbate excessive cervical-flexion ROM, thereby worsening motor unit loss in HD patients. A cautious approach should be taken when treating HD due to possible comorbid GJH.
METHODS: The Beighton scoring system (≥4) was used to diagnose GJH in 84 HD patients. All patients underwent assessments of cervical-flexion/extension ROM; motor unit number estimation in bilateral abductor pollicis brevis (APB) muscles; handgrip strength; and the disabilities of the arm, shoulder, and hand assessments.
RESULTS: Concomitant GJH was identified in 20 (23.8%) HD patients. The HD patients with GJH exhibited greater cervical-flexion (P < .001) and cervical-extension (P = .033) ROM than those without GJH. Both greater single motor unit potential amplitudes (symptomatic side: P = .005; less-symptomatic side: P = .011) and lower motor unit numbers (symptomatic side: P = .008; less-symptomatic side: P = .013) in bilateral APB, along with lower compound muscle action potential amplitudes on the symptomatic-side APB (P = .039), were observed in patients with GJH than those without GJH. There was a mild negative correlation between motor unit number and cervical-flexion ROM in HD patients (symptomatic side: r = -0.239, P = .028; less-symptomatic side: r = -0.242, P = .027).
CONCLUSIONS: The frequency of GJH in HD patients may be higher than in the general population. Importantly, GJH may exacerbate excessive cervical-flexion ROM, thereby worsening motor unit loss in HD patients. A cautious approach should be taken when treating HD due to possible comorbid GJH.
摘要：
目的：一些平山病（HD）患者可能有全身性关节过度活动（GJH），这可能会过度增加颈椎活动范围（ROM），然后恶化HD。本研究的目的是确定HD患者中GJH的频率，并分析GJH对宫颈ROM和HD严重程度的影响。
方法：采用Beighton评分系统（≥4）诊断84例HD患者的GJH。所有患者都接受了颈椎屈曲/伸展ROM的评估；双侧短外展肌（APB）肌肉的运动单位数估计；握力；和手臂的残疾，肩膀,手评估。
结果：在20例（23.8%）HD患者中发现合并GJH。与没有GJH的HD患者相比，GJH的HD患者表现出更大的颈椎屈曲（P<.001）和颈椎伸展（P=.033）ROM。双侧APB中较大的单个运动单位电位幅度（症状侧：P=.005；症状较小侧：P=.011）和较低的运动单位数量（症状侧：P=.008；症状较小侧：P=.013），随着较低的复合肌肉动作电位振幅在症状侧APB（P=0.039），在患有GJH的患者中观察到比没有GJH的患者。HD患者的运动单位数与颈屈曲ROM之间存在轻度负相关（症状侧：r=-0.239，P=.028；症状侧：r=-0.242，P=.027）。
结论：HD患者中GJH的频率可能高于一般人群。重要的是,GJH可能会加剧过度的颈屈曲ROM，从而加重HD患者的运动单位损失。由于GJH可能合并症，治疗HD时应采取谨慎的方法。
方法：采用Beighton评分系统（≥4）诊断84例HD患者的GJH。所有患者都接受了颈椎屈曲/伸展ROM的评估；双侧短外展肌（APB）肌肉的运动单位数估计；握力；和手臂的残疾，肩膀,手评估。
结果：在20例（23.8%）HD患者中发现合并GJH。与没有GJH的HD患者相比，GJH的HD患者表现出更大的颈椎屈曲（P<.001）和颈椎伸展（P=.033）ROM。双侧APB中较大的单个运动单位电位幅度（症状侧：P=.005；症状较小侧：P=.011）和较低的运动单位数量（症状侧：P=.008；症状较小侧：P=.013），随着较低的复合肌肉动作电位振幅在症状侧APB（P=0.039），在患有GJH的患者中观察到比没有GJH的患者。HD患者的运动单位数与颈屈曲ROM之间存在轻度负相关（症状侧：r=-0.239，P=.028；症状侧：r=-0.242，P=.027）。
结论：HD患者中GJH的频率可能高于一般人群。重要的是,GJH可能会加剧过度的颈屈曲ROM，从而加重HD患者的运动单位损失。由于GJH可能合并症，治疗HD时应采取谨慎的方法。
