New bedside finding for carpal tunnel syndrome

New bedside finding for carpal tunnel syndrome. J Hand Surg [Am]. 2008 Nov;33(9):1518-24. PMID: 18984333

At most, this is a new finding to watch for in future research. This study has problems; details are below.

The authors report that in 119 patients with clinically diagnosed carpal tunnel syndrome seen by a single surgeon and 109 controls recruited from a church, the Scratch Collapse test was able to distinguish carpal tunnel syndrome with accuracy of:

• Sensitivity 64%
  
• Specificity 99%

Predictive values and prevalence cannot be calculated since this was not a consecutive sample of patients suspected of having carpal tunnel syndrome.

Problems with this study are:

• Use of case control design rather than a cross sectional study of consecutive patients
• No true reference standard
• Subjective interpretation of an abnormal response