Quantification of the weakness and fatigue in thoracic outlet syndrome with isokinetic measurements.

OBJECTIVES Patients with thoracic outlet syndrome (TOS) complain of many subjective symptoms that are difficult to measure and quantify. In this study we have tried to assess the weakness (muscle strength) and fatigue (endurance) of these patients with an objective measurement method, isokinetic muscle testing. METHODS Twenty three TOS patients and 15 age matched healthy controls were enrolled in the study. Detailed histories of the patients were taken and the patients underwent complete physical examinations. Cervical radiographies, Doppler ultrasonography, electromyography, and isokinetic measurements were carried out. The isokinetic measurements were carried using the Biodex System 3 dynamometer during concentric shoulder flexions and extensions at velocities of 60 degrees /s, 180 degrees /s, and 240 degrees /s. RESULTS Although the muscle strengths of both groups seemed to be similar, the fatigue ratios of TOS patients at 60 degrees /s and 180 degrees /s were found to be higher compared with those of healthy controls (p = 0.029, p = 0.007). CONCLUSIONS TOS patients were found to have muscular performance similar to controls, but their upper extremities developed fatigue more easily than those of healthy individuals.