Correlation of lower extremity functional scale and electrodiagnostic findings in sciatic neuropathy patients

Abstract

Introduction Sciatic nerve has an essential role in sensorimotor innervation of the lower extremities. This study explored the association between electrophysiological findings and lower extremity function in patients with sciatic neuropathy. Materials and Methods This retrospective study analyzed the electrophysiological data of 41 patients with sciatic neuropathy who underwent evaluation between January 2023 and August 2024. Lower extremity function was evaluated with the Lower Extremity Functional Scale (LEFS), while neuropathic pain was assessed using the Douleur Neuropathique 4 (DN4) questionnaire. Results The median LEFS score was 29, reflecting significant functional impairment, while 95.1% of patients exhibited neuropathic pain based on DN4 scores. LEFS scores showed a significant correlation with the compound muscle action potential (CMAP) amplitudes of the abductor hallucis brevis (Spearman rho: 0.52, p < 0.001) and extensor digitorum brevis (Spearman rho: 0.32, p = 0.04) muscles. Conclusion This study provides novel evidence on the critical role of posterior tibial and peroneal nerve dysfunction in lower extremity impairment in sciatic neuropathy patients. The stronger correlation of LEFS with posterior tibial nerve function underscores its importance in high-effort activities. We propose that electrophysiological findings may facilitate a more objective evaluation of functional impairment in sciatic neuropathy patients and aid in the development of targeted rehabilitation strategies.

Keywords

• Sciatic neuropathy
• lower extremity
• neuropathic pain
• electromyography
• nerve conduction studies

Siyatik sinir nöropatisi olan hastalarda elektrofizyolojik bulgular ile alt ekstremite fonksiyonel ölçeğinin korelasyonu

Abstract

Amaç Alt ekstremitelerin sensorimotor innervasyonunun sağlanmasında siyatik sinirin önemli bir rolü vardır. Bu çalışma, siyatik nöropatili hastalarda elektrofizyolojik bulgular ile alt ekstremite fonksiyonları arasındaki ilişkiyi araştırmayı amaçlamaktadır. Gereç ve Yöntem Bu retrospektif çalışmada, Ocak 2023 - Ağustos 2024 tarihleri arasında değerlendirilmiş 41 siyatik nöropati hastasının elektrofizyolojik verileri analiz edilmiştir. Alt ekstremite fonksiyonları Alt Ekstremite Fonksiyonel Ölçeği ile değerlendirilirken, nöropatik ağrı varlığı ve şiddeti Douleur Neuropathique 4 (DN4) anketi ile ölçülmüştür. Bulgular Alt ekstremite fonksiyonel ölçeği medyan skoru 29 olup hastalardaki ciddi fonksiyonel kaybı göstermektedir. DN4 ölçeğine göre hastaların %95.1’inde nöropatik ağrı saptanmıştır. Alt ekstremite fonksiyonel ölçeği skorları ile abductor hallucis brevis (Spearman rho: 0.52, p < 0.001) ve extensor digitorum brevis (Spearman rho: 0.32, p = 0.04) kaslarından kaydedilen bileşik kas aksiyon potansiyeli amplitüdü arasında anlamlı bir korelasyon saptanmıştır. Sonuç Bulgularımız, siyatik nöropati hastalarında posterior tibial ve peroneal sinirlerin disfonksiyonunun alt ekstremite fonksiyon kaybındaki kritik rolünü ortaya koymaktadır. Alt ekstremite fonksiyonel ölçeği skorları ile posterior tibial sinir fonksiyonunun daha güçlü bir korelasyon göstermesi, bu sinirin alt ekstremitenin efor gerektiren aktivitelerindeki önemini göstermektedir. Siyatik nöropati hastalarında elektrofizyolojik bulgular, fonksiyonel kaybın daha objektif bir şekilde değerlendirilmesine katkı sağlayabilir ve hedefe yönelik rehabilitasyon stratejilerinin geliştirilmesine yardımcı olabilir.

Keywords

• Siyatik sinir nöropatisi
• nöropatik ağrı
• elektromiyografi
• sinir iletim çalışması

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