Assessing the accuracy of a combination of clinical tests for identifying carpal tunnel syndrome

Abstract

The aim of the study was to investigate whether a combination of selected provocative manoeuvres and sensory testing could improve the accuracy of clinical diagnosis of carpal tunnel syndrome (CTS). Prospective studies were undertaken in 43 of 296 consecutive patients who were referred with suspected CTS and had undergone nerve conduction studies (NCS). Responses to Phalen’s test, a modified carpal compression test (MCCT), and sensory testing over the thenar eminence were assessed for each patient. For each test (Phalen’s; MCCT), sensitivity (0.64; 0.14), specificity (0.75; 0.96), positive likelihood ratio (PLR) (2.54; 3.64) and negative likelihood ratio (NLR) (0.49; 0.89) were calculated. The inclusion of sensory testing did not improve sensitivity (0.55; 0.13), specificity (0.75; 0.96), PLR (2.22; 3.29) or NLR (0.60; 0.91). These data indicate that assessment of thenar sensation does not improve the diagnostic accuracy of CTS. However, a positive Phalen’s test is more likely to be associated with NCS changes that are consistent with CTS.