Management of cervical ribs and anomalous first ribs causing neurogenic thoracic outlet syndrome.

OBJECTIVE: Cervical and anomalous first ribs are rare conditions, occurring in less than 1% of the population. This manuscript reviews our management of neurogenic thoracic outlet syndrome (TOS) associated with these congenital anomalies.
METHODS: During the past 26 years, 65 operations were performed for abnormal ribs that produced symptoms of TOS. Of these, 54 operations were for neurogenic TOS and are covered in this paper. Indications for surgery were disabling pain and paresthesia and failure to respond to conservative treatment. Surgical technique for neurogenic TOS was supraclavicular cervical rib resection and scalenectomy without first rib resection in 22 cases, supraclavicular cervical and first rib resection in 17 cases, supraclavicular excision of anomalous first ribs in five cases, and transaxillary anomalous first rib resections in two cases (total, 46 cases). Eight reoperations were performed for recurrent TOS in patients who previously had undergone cervical and first rib resections.
RESULTS: Neck trauma was the cause of neurogenic symptoms in 80% of patients with cervical or anomalous first ribs. The surgical failure rate was 28% for 46 primary operations. A significant variable in results was the etiology of the symptoms. The failure rate for patients in whom symptoms developed after work-related injuries or repetitive stress at work was 42%, and the failure rates for patients whose symptoms followed an auto accident or developed spontaneously were 26% and 18%, respectively. The failure rate in each etiology group also was affected by the operation performed. The failure rate for cervical rib resection without first rib resection in the work-related group was 75% compared with a failure rate of 38% in the non-work-related group. In contrast, when both cervical and first ribs were resected, the failure rate in the work-related group fell to 25% and in the non-work-related group to 20%. These failure rates for the work-related and non-work-related groups are similar to our failure rates in patients without cervical ribs.
CONCLUSION: Surgery for neurogenic TOS in patients with cervical ribs should include both cervical and first rib resection. The presence of cervical or anomalous first ribs in patients with neurogenic TOS does not improve the success rate from surgery compared with patients without abnormal ribs. Neck trauma is the most common cause for neurogenic TOS in patients with abnormal ribs. Cervical and anomalous first ribs are the predisposing factors rather than the cause.