Raju Viprav B, Hauer Roxanne, Jalloh Mohamed, Banerjee Anjishnu, Hyngstrom Allison, Schmit Brian D, Vedantam Aditya
Department of Neurosurgery, Medical College of Wisconsin, Milwaukee, WI, USA.
Joint Department of Biomedical Engineering, Marquette University-Medical College of Wisconsin, Milwaukee, WI, USA.
Geroscience. 2025 Sep 6. doi: 10.1007/s11357-025-01875-4.
Degenerative cervical myelopathy (DCM) is a leading cause of non-traumatic spinal cord disorders in older adults. Gait instability and balance dysfunction are common in DCM, even in the absence of clinically evident lower limb weakness. We hypothesized that subclinical weakness, measured through maximal voluntary isometric contractions (MVICs) of the knee extensors and ankle plantar flexors, is associated with impaired gait and balance in individuals with DCM. Pre-surgical DCM participants with symptoms of DCM and MRI evidence of cervical spinal cord compression were prospectively enrolled in this observational study. Knee extensor and ankle plantar flexor MVICs of the self-reported most-affected leg were measured using a Biodex system. Berg Balance Scale (BBS) scores, gait speed and spatiotemporal gait parameters, and the modified Japanese Orthopedic Association score (mJOA) were recorded. Multivariable regression assessed associations between MVICs and gait/balance outcomes, controlling for age and sex. Data from 32 DCM participants (11 females; mean age 59.1 ± 10.7 years) were analyzed. Knee extensor MVICs showed significant positive correlations with gait speed (r = 0.38, p = 0.001), mJOA lower extremity scores (r = 0.41, p = 0.019), and BBS scores (r = 0.44, p = 0.007). These associations remained significant in multivariable linear regression models adjusted for age and sex. Ankle plantar flexor MVICs were not significantly associated with any outcomes (p > 0.05). Knee extensor MVICs reflect subclinical lower extremity weakness and are associated with impaired gait and balance in DCM. MVIC is a promising objective method to quantify motor impairment in DCM.
退行性颈椎脊髓病（DCM）是老年人非创伤性脊髓疾病的主要病因。步态不稳和平衡功能障碍在DCM中很常见，即使在没有明显临床下肢无力的情况下也是如此。我们假设，通过膝伸肌和踝跖屈肌的最大自主等长收缩（MVIC）测量的亚临床无力与DCM患者的步态和平衡受损有关。有DCM症状且有颈椎脊髓受压MRI证据的术前DCM参与者被前瞻性纳入本观察性研究。使用Biodex系统测量自我报告受影响最严重的腿的膝伸肌和踝跖屈肌MVIC。记录伯格平衡量表（BBS）评分、步态速度和时空步态参数，以及改良日本骨科协会评分（mJOA）。多变量回归评估MVIC与步态/平衡结果之间的关联，并对年龄和性别进行控制。分析了32名DCM参与者（11名女性；平均年龄59.1±10.7岁）的数据。膝伸肌MVIC与步态速度（r = 0.38，p = 0.001）、mJOA下肢评分（r = 0.41，p = 0.019）和BBS评分（r = 0.44，p = 0.007）呈显著正相关。在根据年龄和性别调整的多变量线性回归模型中，这些关联仍然显著。踝跖屈肌MVIC与任何结果均无显著关联（p>0.05）。膝伸肌MVIC反映亚临床下肢无力，并与DCM患者的步态和平衡受损有关。MVIC是一种很有前景的量化DCM运动障碍的客观方法。
