An investigation of the relationship between thoracic outlet syndrome and the dimensions of the first rib and clavicle

Introduction: Abnormalities of the first rib including rib width, rib shape and rib angulation were noted intra-operatively in our thoracic outlet syndrome (TOS) operative patients. The purpose of this study is to investigate the relationship between TOS and the first rib in TOS operative patients and normal population. Methods: Between 1993 and 2003, 32 patients with TOS undergoing surgical decompression and 30 normal subjects as the control group were included in this investigation. The investigation was from posteroanterior chest and antero-posterior C-spine radiographs. Sternal head width and vertebral head width of the first rib were measured. In addition, sternal head width, the acromion head width and the length of the clavicle were measured for comparison. Comparison between affected side and unaffected side first ribs was also performed in the unilateral TOS patients. Results: In TOS patients, the widths of the vertebral end and sternal end of the first rib were significantly wider than the control group (both, P = 0.0001). Conclusion: Patients with wider vertebral end width of the first rib (>15 mm) or wider sternal end width of the first rib (>20 mm) may develop TOS.