The diagnostic contribution of motor and sensory conduction studies of the wrist-palm segment in carpal tunnel syndrome

Abstract

Aim: Sensory and motor segmental conduction studies have been performed to improve diagnostic sensitivity especially in cases with mild carpal tunnel syndrome, but there are very few studies comparing these methods. The purpose of this study was to determine the segmental conduction studies' contribution to the diagnosis of carpal tunnel syndrome (CTS), to compare the sensitivity and specificity of these methods.

Methods: Patients with suspected CTS referred to our electrophysiology laboratory and a control group was included. The data were collected prospectively. The following measurements made: median sensory conduction velocity wrist- digit 1 (W-1), median sensory conduction velocity wrist- digit 3 (W-3), median wrist-palm sensory conduction velocity (W-Ps), distoproximal ratio of velocity (D/P), median distal motor latency wrist- APB (MDML), median wrist- palm segment motor conduction velocity (W-Pm).

Results: The highest sensitivity for an electrodiagnostic CTS diagnosis were W- Pm (38%), D/P (33.3%), MDML (33.3%), W- 3 (31%), W- 1 (31%), W-Ps (24%), respectively. Seventeen out of 42 hands presented one or more abnormal results of routine electrophysiologic tests (W-1, W-3, MDML). Twenty-one patients were diagnosed CTS electrophysiologically after inclusion of D/ P and 24 patients were defined CTS after inclusion of W- Pm. Twenty-five of 42 hands with CTS were defined as an electrophysiologically proven CTS using routine electrophysiologic tests together with both D/P and W-Pm segmental studies. That is; diagnostic sensitivity increased nearly by 50%. 

Conclusion: The results of this study suggested that motor or sensory segmental studies have an important contribution to the diagnosis, particularly for mild subjects. 

Keywords

• Carpal tunnel syndrome,Segmental conduction study

Karpal tünel sendromunda bilek-aya segmenti motor ve duysal iletim çalışmalarının tanıya katkısı

Öz

Amaç: Özellikle hafif karpal tünel sendromu olan olgularda tanı duyarlılığını artırmak için duysal ve motor segmental iletim çalışmaları yapılmıştır, ancak bu yöntemleri birbiriyle karşılaştıran çok az sayıda çalışma vardır. Bu çalışmanın amacı segmental iletim çalışmalarının karpal tünel sendromu (KTS) tanısına katkısını saptamak, bu yöntemlerin duyarlılığını ve özgüllüğünü birbiriyle karşılaştırmaktır.

Yöntemler: KTS şüphesiyle elektrofizyoloji laboratuvarına gönderilen hastalar ile bir kontrol grubu dahil edildi. Veriler prospektif olarak toplandı. Bilek- 1. parmak median duysal iletim hızı (W-1), bilek- 3. parmak median duysal iletim hızı (W-3), median bilek- aya duysal iletim hızı (W- Ps), distoproksimal hız oranı (D/P), bilek- APB median distal motor latansı (MDML), median bilek- aya segmenti motor iletim hızı (W-Pm).

Bulgular: Elektrofizyolojik KTS tanısı için sensitivitesi en yüksekler sırasıyla W- Pm (%38), D/P (%33,3), MDML (%33,3), W- 1 (%31), W- Ps (%24)' di. 42 elden 17' sinde rutin elektrofizyolojik testlerde (W-1, W-3, MDML) bir veya daha fazla anormal sonuç elde edildi. D/P eklendikten sonra 21 hasta elektrofizyolojik olarak KTS tanısı aldı ve W- Pm eklendikten sonra 24 hasta KTS olarak değerlendirildi. Rutin elektrofizyolojik testlere ek olarak hem D/P, hem W- Pm segmental çalışmalarının eklenmesiyle 25 hastaya elektrofizyolojik olarak KTS tanısı kondu. Böylece; tanısal duyarlılık yaklaşık %50 arttı. 

Sonuç: Bu çalışmanın sonuçları göstermiştir ki; özellikle hafif olgularda motor ve duysal segmental çalışmalar tanıya önemli katkı sağlamaktadır.

Anahtar Kelimeler

• Karpal tünel sendromu,Segmental iletim çalışması

Kaynakça

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