Discriminatory sonographic criteria for the diagnosis of carpal tunnel syndrome

Abstract

Objective. Sonographic examination of the median nerve has been suggested as a useful alternative to electrophysiologic study in the diagnosis of carpal tunnel syndrome. To determine its usefulness and the best diagnostic criterion, sonograms of patients with the disease were compared with sonograms of healthy subjects in a case-control study.Methods. Patients with carpal tunnel syndrome and asymptomatic controls who were matched for age and sex were enrolled and underwent sonography of the wrists. Eight separate sonographic criteria were analyzed in each wrist. Data from the patient group and the control group were compared to establish optimal diagnostic criteria for carpal tunnel syndrome, using receiver operating characteristic analytic techniques.Results. Thirty-five patients with carpal tunnel syndrome and 35 asymptomatic controls were examined. Increased cross-sectional area of the median nerve was found to be the most predictive measure of carpal tunnel syndrome, proximal to the tunnel inlet, at the tunnel inlet, and at the tunnel outlet, with significant differences between patients and controls. Using a receiver operating characteristic curve, a cut-off value >0.098 cm 2 at the tunnel inlet provided a diagnostic sensitivity of 89% and a specificity of 83%.Conclusion. Sonographic measurement of the median nerve cross-sectional area is both sensitive and specific for the diagnosis of carpal tunnel syndrome.A diagnosis of carpal tunnel syndrome (CTS) is usually based on symptom characteristics and confirmatory neurophysiologic evaluation (1). Sonographic examination of the median nerve in CTS has been proposed as a useful alternative to neurophysiologic study in the diagnosis of CTS, and proposals for different criteria have been presented (2-7), as summarized in Table 1. The lack of consensus on the optimal criteria for CTS may be attributable to differences in equipment, patient populations, and sonographic techniques. These discrepancies underscore the need for each center to validate internally the criteria it uses to diagnose CTS with ultrasound.This study aimed to prospectively evaluate the characteristics of the median nerve in CTS patients against the findings in normal, healthy subjects, to elicit the optimal discriminatory sonographic criteria and relevant threshold values. PATIENTS AND METHODSCases and controls. This was a prospective, agematched case-control study of CTS in a cohort comprised solely of women, since women account for the majority of CTS patients in the local population (8). The study ethics were reviewed and approved, and patients gave their written informed consent. Consecutive CTS patients from our neurology and rheumatology clinics were invited to join the study. Patients were enrolled into the study after electrophysiologic examination, if the following criteria were fulfilled: 1) presence of sensory symptoms over the median nerve distribution, and 2) confirmatory neurophysiologic results (prolonged median nerve distal motor latencies Ͼ4 ms or a median-ulnar palmer sensory ...

Sonographic short-term follow-up after surgical decompression of the median nerve at the carpal tunnel: a single-center prospective observational study

“…5,6,16,17 In addition to contributing to the diagnostic workup of patients with suspected CTS, sonographic examination allows noninvasive detection of aberrations. 4,9,10 In our investigation, however, electrodiagnostic studies seemed to be more sensitive in picking up preoperative deficits-our patients with motor deficits had statistically significantly longer preoperative dmL (10.5 ± 2.8 msec vs 6.5 ± 2.3 msec; p = 0.021 in multivariate analysis), but not greater CSA (p = 0.124) or circumference (p = 0.252).…”

Use of Sonography in Carpal Tunnel Syndrome Surgery-A Prospective Study-

“…7,8,11,17,21,34) Increase in the swelling ratio, or the cross-sectional area at the level of the pisiform bone compared to the area at the level of distal radius, is another sonographic indicator. 7,8,37) The changes in the cross-sectional area values between pre-and postoperative studies for each level are also meaningful. Cross-sectional areas smaller than the cut-off points may be observed in patients with axonal degenerative changes of nerves already confirmed by nerve conduction studies.…”

“…Recently, sonography has been evaluated for the evaluation of patients with CTS, 3,11,[16][17][18][19]21,25,28,31,32,34,35,37) and may be a useful alternative to the nerve conduction study, 7,11,20,21,23,31,34,38) with high sensitivity and specificity. 3,11,25,31,32,34,37) Most studies used nerve conduction as the gold standard.…”

“…3,11,25,31,32,34,37) Most studies used nerve conduction as the gold standard. A few surgical studies also utilized sonography to identify CTS.…”

Ultrasound Assessment of the Motion Patterns of Human Flexor Digitorum Superficialis and Profundus Tendons With Speckle Tracking

“…Although ultrasound has been used to diagnose hand and wrist diseases (21)(22)(23) , less use has been made of its potential value in dynamically assessing tendon mechanics. In this study, we used ultrasound to analyze the relative motions of flexor tendons according to joint angle using speckle tracking.…”