Section of Neurology, Department of Medicine, Aga Khan University Hospital, Karachi, Pakistan.
Department of Medicine, Aga Khan University Hospital, Karachi, Pakistan.
BMC Neurol. 2024 Oct 24;24(1):413. doi: 10.1186/s12883-024-03851-5.
The saphenous nerve, a sensory branch of the femoral nerve, is not commonly included in routine lower extremity nerve conduction studies due to a high frequency of non-recordable responses in healthy subjects. However, saphenous nerve conduction studies are sometimes utilized for the diagnostic assessment of isolated lumbosacral plexus, femoral, or saphenous mononeuropathies. Our study aims to determine normative saphenous nerve response values in a healthy Pakistani population and to investigate their associations with patient body mass index, age, and gender.
This cross-sectional descriptive study was undertaken over a 3‑month period (May to July 2021) at a neurophysiology department of a tertiary care center in Pakistan. Healthy subjects underwent neurological examination, anthropometric measurements, and bilateral SN nerve conduction studies, with recording of peak-latency, peak-to-peak amplitude and conduction velocity. Statistical analyses and linear regression were conducted to evaluate associations between nerve conduction study variables and patient characteristics. Statistical analyses were also run to assess patient characteristics affecting recordability of saphenous nerve responses. A p-value < 0.05 was considered statistically significant.
Among 117 subjects, 79.5% (n = 93) had recordable saphenous nerve responses. Median peak-latency, amplitude, and conduction velocity were 3.2 (3.0-3.3) m/s, 7.7 (5.8-9.9) uV, and 44.0 (42.0-47.0) m/s, respectively. Bilaterally absent responses were observed in 20.5% (n = 24) of subjects. Obese participants had a significantly higher number of absent saphenous responses (p = 0.033). Females had shorter peak-latency (p = 0.006) and higher conduction velocity (p = 0.012).
Saphenous nerve responses can be used to assess unilateral femoral and saphenous nerve pathologies, provided they are recordable on the asymptomatic side for comparison. Absent bilateral saphenous nerve responses should be interpreted with caution given their prevalence in healthy individuals. Patient characteristics should be taken into consideration when interpreting recordable and nonrecordable saphenous nerve responses.
隐神经是股神经的感觉支，由于在健康受试者中经常出现无法记录的反应，因此通常不包括在常规下肢神经传导研究中。然而，隐神经传导研究有时用于孤立的腰骶丛、股神经或隐神经单神经病的诊断评估。我们的研究旨在确定巴基斯坦健康人群中隐神经反应的正常值，并探讨其与患者体重指数、年龄和性别之间的关系。
这是一项在巴基斯坦一家三级保健中心的神经生理科进行的横断面描述性研究，研究时间为 3 个月（2021 年 5 月至 7 月）。健康受试者接受了神经学检查、人体测量学测量和双侧 SN 神经传导研究，记录了潜伏期、峰峰值幅度和传导速度。进行了统计学分析和线性回归，以评估神经传导研究变量与患者特征之间的关系。还进行了统计学分析，以评估影响隐神经反应可记录性的患者特征。p 值<0.05 被认为具有统计学意义。
在 117 名受试者中，79.5%（n=93）有可记录的隐神经反应。潜伏期、幅度和传导速度的中位数分别为 3.2（3.0-3.3）m/s、7.7（5.8-9.9）uV 和 44.0（42.0-47.0）m/s。双侧无反应的受试者占 20.5%（n=24）。肥胖受试者的隐神经无反应明显更多（p=0.033）。女性的潜伏期更短（p=0.006），传导速度更高（p=0.012）。
隐神经反应可用于评估单侧股神经和隐神经病变，前提是在无症状侧可记录到反应以便进行比较。双侧隐神经无反应应谨慎解释，因为在健康个体中较为常见。在解释可记录和不可记录的隐神经反应时，应考虑患者特征。
