Carpal tunnel syndrome (CTS) is the most common form of peripheral nerve entrapment. Electromyography with selected nerve conduction studies (NCS) is an accepted diagnostic tool in CTS patients. Ultrasonography presents a widely available and low cost investigation method and its position in CTS diagnostics needs further clarification with concrete recommendations for clinical practice. A prospective study of 37 patients with 74 wrists (59 wrists with suspected CTS) was done. Normative data were obtained from a control group of 25 healthy persons (50 wrists) age and sex matched. All persons underwent ultrasonographic examination (median nerve cross-sectional area at carpal tunnel entrance measurement--CSA) and median NCS studies (distal motor and sensory latency measurement--DML and DSL).
Results: CSA has a sensitivity of 93% (CI 84-97%) and specificity of 96% (CI 87-99%) in our patients group. Conventional first-line NCS studies results in our patients groupare as follows: DML sensitivity 58% (CI 45-69%) and specificity 100% (CI 93-100%); DSL sensitivity 88% (CI 78-94%) and specificity 94% (CI 84-98%).
Conclusion: We recommend the use of single-parameter wrist ultrasonography as a first-line screening laboratory method in suspected CTS diagnosis (Ref. 14). Full Text (Free, PDF) www.bmj.sk.