KARPAL TÜNEL SENDROMU TANISINDA DİJİTAL DALLARDA MEDİAN SİNİR DUYU İLETİM TESTLERİNİN DUYARLILIĞI

Öz

Amaç: Elektrofizyolojik olarak hafif-orta düzey karpal tünel sendromu (KTS) tanısı alan olgularda, median sinirin dijital dalları ve avuç içi-bilek segmentine yönelik duyu ileti testlerinin tanısal duyarlılığını değerlendirmek ve birden fazla segmentin kombine edilmesinin tanı başarısını artırıp artırmadığını incelemektir. Gereç ve Yöntem: Bu kesitsel çalışmaya, 2020–2022 yılları arasında KTS ön tanısıyla elektrofizyolojik değerlendirmeye yönlendirilen hastalardan elde edilen 217 el dahil edilmiştir. Birinci (1PB), ikinci (2PB) ve üçüncü (3PB) parmak-bilek segmentlerine ile avuç içi-bilek (AİB) segmentine ortodromik duyu ileti çalışması yapılmıştır. Laboratuvara özgü referans sınır değerleri 73 sağlıklı kontrolden türetilmiştir. Her segmentin duyarlılığı tekil ve kombine olarak hesaplanmıştır. Bulgular: En yüksek duyarlılık AİB segmentinde (%98,62) saptanmış, bunu sırasıyla 1PB (%96,31), 3PB (%94,47) ve 2PB (%92,63) izlemiştir. AİB ile 1PB'nin birlikte değerlendirilmesiyle %100 duyarlılığa ulaşılmış; AİB+3PB ve AİB+2PB kombinasyonlarında bu oran sırasıyla %99,6 ve %99,1 olarak saptanmıştır. Sonuç: Yalnızca tek bir dijital segmentin değerlendirilmesi bazı KTS olgularının tanısının atlanmasına yol açabilir. AİB segmentinin herhangi bir parmak-bilek segmentiyle kombinasyonu duyarlılığı %99'un üzerine taşıyarak yanlış negatif oranını önemli ölçüde azaltmaktadır. Rutin KTS elektrofizyolojik değerlendirmesine AİB segmentinin dahil edilmesi güçlü biçimde önerilmektedir.

Anahtar Kelimeler

• karpal tünel sendromu
• median sinir
• duyusal sinir iletimi
• duyarlılık
• elektrodiagnosis

Destekleyen Kurum

Bu araştırma, herhangi bir kamu, ticari veya kar amacı gütmeyen kuruluştan özel bir finansal destek almamıştır.

Etik Beyan

Bu çalışma, Karabük Üniversitesi Girişimsel Olmayan Klinik Araştırmalar Etik Kurulu tarafından onaylanmıştır (Onay No: 2022/893). Çalışma, Helsinki Bildirgesi ilkeleri doğrultusunda yürütülmüştür. Tüm katılımcılardan çalışmaya dahil edilmeden önce yazılı bilgilendirilmiş onam alınmıştır.

Teşekkür

Yazarlar, bu çalışmaya gönüllü olarak katılan tüm katılımcılara teşekkür eder. Makalenin hazırlanmasında herhangi bir dış destek alınmamıştır.

Sensitivity of Median Nerve Sensory Conduction Studies in the Digital Branches for the Diagnosis of Carpal Tunnel Syndrome

Öz

Aim: To evaluate the diagnostic sensitivity of sensory conduction studies targeting the digital branches and the palm-to-wrist segment of the median nerve in patients with electrophysiologically confirmed mild-to-moderate carpal tunnel syndrome (CTS), and to assess whether combining multiple segments improves diagnostic yield. Materials and Methods: This cross-sectional study included 217 hands from patients referred for electrophysiological evaluation between 2020 and 2022 with a preliminary CTS diagnosis. Orthodromic sensory conduction studies were performed on the first (D1W), second (D2W), and third (D3W) digit-to-wrist segments and the palm-to-wrist (PW) segment. Laboratory-specific reference limits were established from 73 healthy controls. Sensitivity was calculated for each segment individually and in combination. Results: The PW segment demonstrated the highest sensitivity (98.62%), followed by D1W (96.31%), D3W (94.47%), and D2W (92.63%). Combining PW with D1W achieved 100% sensitivity; PW combined with D3W and D2W yielded 99.6% and 99.1%, respectively. Conclusion: Testing a single digital segment alone may miss CTS diagnoses in some patients. Combining the PW segment with any digit-to-wrist segment raises sensitivity above 99%, substantially reducing false-negative rates. To minimize false-negative rates, combining the PW segment with at least one digit-to-wrist segment is recommended in routine CTS electrophysiological evaluation, particularly when digital branch studies yield normal or borderline results.

Anahtar Kelimeler

• carpal tunnel syndrome
• median nerve
• sensory nerve conduction
• sensitivity
• electrodiagnosis

Destekleyen Kurum

The author declared that this study has received no financial support.

Etik Beyan

The study was approved by the Karabuk University Non-Interventional Clinical Research Ethics Committee (Approval No: 2022/893).

Teşekkür

The authors would like to thank all participants who volunteered for this study. No external assistance was received in the preparation of this manuscript.

Kaynakça

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