Thoracic outlet syndrome

Outcomes of Surgical Management of Neurogenic Thoracic Outlet Syndrome: A Systematic Review and Bayesian Perspective

PURPOSE

To provide a summary of the relevant evidence on outcomes of transaxillary first rib excision (TAFRE), supraclavicular first rib excision with scalenectomy (SCFRE), and supraclavicular release leaving the first rib intact (SCR) for patients with neurogenic thoracic outlet syndrome (TOS), and interpret the treatment effects from a Bayesian perspective.

METHODS

A systematic literature search and review were performed. Random-effects meta-analyses were conducted to estimate success rate and complete relief rate of each procedure. The probabilities of specified success rates and complete relief rates were calculated using a Bayesian method. Sensitivity analyses for TOS type, neck trauma, and cervical rib were performed. Complications of each procedure were also reviewed.

RESULTS

Data were extracted from 17 studies of TAFRE, 9 of SCFRE, and 14 of SCR to conduct the meta-analyses. The pooled success rate and complete relief rate were 0.76 (95% confidence interval [95% CI)], 0.65-0.85) and 0.53 (95% CI, 0.38-0.68) for TAFRE, 0.77 (95% CI, 0.68-0.85) and 0.57 (95% CI, 0.41-0.72) for SCFRE, and 0.85 (95% CI, 0.76-0.92) and 0.61 (95% CI, 0.35-0.84) for SCR, respectively. The probabilities of success rate greater than 70% were 90%, 87%, and 99% for TAFRE, SCFRE, and SCR, respectively. If the success rate of 80% or greater was considered, the probabilities were 34%, 31%, and 91%, respectively. The probabilities of complete relief rate of 50% or greater were 67%, 71%, and 69% for TAFRE, SCFRE, and SCR, respectively. Sensitivity analyses showed similar results. The complication rates for TAFRE, SCFRE, and SCR were, respectively, 22.5%, 25.9%, and 12.6%.

CONCLUSIONS

The SCR has a high probability of success rate greater than 80%; both TAFRE and SCFRE have high probabilities of a success rate greater than 70% but only low probabilities of success rate greater than 80%. The TAFRE and SCFRE have more complications than SCR.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Vascular injuries in the upper extremity in athletes

Repetitive, high-stress, or high-impact arm motions can cause upper extremity arterial injuries. The increased functional range of the upper extremity causes increased stresses on the vascular structures. Muscle hypertrophy and fatigue-induced joint translation may incite impingement on critical neurovasculature and can cause vascular damage. A thorough evaluation is essential to establish the diagnosis in a timely fashion as presentation mimics more common musculoskeletal injuries. Conservative treatment includes equipment modification, motion analysis and adjustment, as well as equipment enhancement to limit exposure to blunt trauma or impingement. Surgical options include ligation, primary end-to-end anastomosis for small defects, and grafting.

Endoscopic assisted transaxillary first rib resection ☆

OBJECTIVES

Endoscopic assisted transaxillary first rib resection is a novel approach in the management of thoracic outlet syndrome. It allows safe identification of the different structures. The objective of our study is to assess the outcome of surgical treatment of thoracic outlet syndrome using this technique.

METHODS

Between May 1999 and October 2005, 28 endoscopic assisted transaxillary first rib resections were performed on 20 patients with thoracic outlet syndrome in our vascular unit. This retrospective study included 14 females and 6 males with ages ranging between 16 and 53 years (median 37 years).

RESULTS

Prior to the operation, all patients had C spine X-ray and 45% (nine patients) had nerve conduction studies prior to the operation. Duration of symptoms ranged between 1 month and 15 years (median 36 months). Fifty-five percent of patients had neurological symptoms, 30% had mixed symptoms and only 15% had venous or arterial symptoms. Eight patients were given bilateral first rib excision. The average time between the two operations was 17.5 months (median 12 months). The postoperative stay in hospital ranged between 2 and 8 days (median 5 days). Follow-up ranged between 1 and 64 months (median 8 months). Eighty-two percent of patients (23 resections) had complete resolution of symptoms. Eighteen percent (5 resections) did not show any improvement of symptoms following surgery. Three complications were recorded, including haemothorax, bleeding and brachial plexus injury. The latter was due to traction injury during the operation.

CONCLUSIONS

Endoscopic assisted transaxillary first rib resection is a safe and effective procedure in the management of thoracic outlet syndrome. It also offers a great opportunity for teaching.

Nerve injury about the shoulder in athletes, part 2: long thoracic nerve, spinal accessory nerve, burners/stingers, thoracic outlet syndrome

Nerve injuries about the shoulder in athletes are being recognized with increasing frequency. Prompt and correct diagnosis of these injuries is important to treat the patient and to understand the potential complications and natural history, so as to counsel our athletes appropriately. This 2-part article is a review and an overview of the current state of knowledge regarding some of the more common nerve injuries seen about the shoulder in athletes, including long thoracic nerve, spinal accessory nerve, burners and stingers, and thoracic outlet syndrome. Each of these clinical entities will be discussed independently, reviewing the anatomy, mechanism of injury, patient presentation (history and examination), the role of additional diagnostic studies, differential diagnosis, and management.

Experience of supraclavicular exploration and decompression for treatment of thoracic outlet syndrome

The purpose of this study was to assess the symptomatic outcome of patients with thoracic outlet syndrome who underwent decompression of the thoracic outlet. In our unit we prefer the supraclavicular approach, performing anterior scalenectomy with excision of fibrous bands or cervical ribs if present. Operative details were gained by theater logbook and case note review. Over a 6-year period, 31 patients (37 limbs) underwent thoracic outlet decompression. Of the 37 affected limbs, the indications for surgery were a combination of both neurological and vascular symptoms in 24 patients (65%), neurological symptoms in 24 (65%), and 4 patients (11%) had vascular symptoms alone. All patients were assessed for postoperative outcome either at out-patient clinics or by personal contact. From the results of this study we concluded that supraclavicular scalenectomy and cervical rib excision with selective first rib excision is a safe and effective procedure for most patients with thoracic outlet syndrome.

A comparison of surgery for neurogenic thoracic outlet syndrome between laborers and nonlaborers

OBJECTIVE

To determine factors of outcome following surgical intervention for neurologic thoracic outlet syndrome (NTOS).

METHODS

In a retrospective study of patients surgically treated for NTOS, outcome was evaluated by postoperative symptoms and the ability of patients to return to work.

RESULTS

Good, fair, and poor results were obtained in 26 (48%), 21 (39%), and 7 (13%) patients, respectively. The best predictor of a good outcome was occupation. Nonlaborers were more likely to have good outcome (21 of 32, 66%) when compared with laborers (5 of 22, 23%; P = 0.0025). Only 6 of 20 (30%) laborers were able to return to their original occupation compared with 17 of 26 (65%) nonlaborers (P = 0.036).

CONCLUSIONS

Laborers with NTOS are less likely to have a good result from surgical intervention, are unlikely to return to their original occupation, and may require retraining for a non-labor-intensive occupation if they cannot return to their original work.

Diagnosis of thoracic outlet syndrome using electrophysiologically guided anterior scalene blocks

There is no "gold standard" for diagnosing thoracic outlet compression syndrome (TOS), however, anesthetic blocks of the anterior scalene muscle (ASM) have been used as a means of predicting which patients may benefit from surgical decompression. The standard technique of using surface landmarks often results in inadvertent somatic block and sympathetic block because there is no reliable verification of needle tip localization. The present study was undertaken to determine if needle tip localization can be improved by using electrophysiological guidance. ASM blocks were performed for patients with a diagnosis of possible TOS. An insulated hypodermic needle was inserted into the ASM which was identified during electromyogram (EMG) activation maneuvers. Stimulation was performed to make sure that the needle tip was not in the brachial plexus. Local anesthetic was instilled and the intensity of pain induced by TOS stress maneuvers was compared to pain ratings obtained after control injections. The ASM could be identified electromyographically in all 122 cases. There were no instances of inadvertent somatic block nor sympathetic block. Of 38 patients who underwent surgical decompression of the thoracic outlet, 30 of 32 (94%) with a positive block had a good outcome compared with 3 of 6 (50%) who underwent surgery in spite of a negative block. Electrophysiological guidance facilitates accurate needle tip placement in the performance of ASM blocks; the results of these blocks appear to correlate with surgical outcomes.

The false-positive rate of thoracic outlet syndrome shoulder maneuvers in healthy subjects

OBJECTIVE

To estimate the incidence of false-positive findings of thoracic outlet syndrome (TOS) shoulder maneuvers, Adson's test (AT), costoclavicular maneuver (CCM), elevated arm stress test (EAST), and supraclavicular pressure (SCP) in healthy subjects.

METHODS

A cross-sectional, observational study was performed in a medical school and affiliated emergency medicine residency program setting. Participants included healthy adult volunteers without symptoms of TOS. The shoulder maneuvers AT, CCM, EAST, and SCP were performed in randomized order for 30 sec, 30 sec, 3 min, and 30 sec, respectively. Pulse quality and the presence and timing of pain or paresthesias were assessed.

RESULTS

53 subjects were enrolled, including 27 women, aged 29.7 +/- 6.4 years (range 21-58 years). AT, CCM, EAST, and SCP resulted in an altered pulse in 11%, 11%, 62%, and 21%; pain in 0%, 0%, 21%, and 2%; and paresthesias in 11%, 15%, 36%, and 15% of cases, respectively. The following outcomes had reasonable false-positive rates (upper 95% confidence limit): pain with the AT (7%), CCM (7%), SCP (10%), or any 2 TOS shoulder maneuvers (10%); discontinuing the EAST because of symptoms (16%); or any symptom with 3 (13%) or 4 (7%) TOS shoulder maneuvers.

CONCLUSIONS

In a study of TOS shoulder maneuvers in healthy subjects, the outcomes of pulse alteration or paresthesias were unreliable in general. However, TOS shoulder maneuvers have reasonably low false-positive rates when a positive outcome is defined as pain after AT, CCM, or SCP; discontinuation of the EAST secondary to pain; pain in the same arm with > or =2 maneuvers; or any symptom in the same arm with > or =3 maneuvers.

770 consecutive supraclavicular first rib resections for thoracic outlet syndrome

During a 28-year period, 637 patients underwent 770 supraclavicular first rib resections and scalenectomies for thoracic outlet syndrome (TOS). The neurologic type of TOS was found in 705 cases (92%) and the remaining 65 cases (8%) had the vascular form of TOS. Of those extremities with brachial plexus irritation, the symptom complex consisted of paresthesia in 30 (4%), pain in 221 (31%), and pain with paresthesia in 454 (64%). In the cases of vascular TOS, 47 limbs (6%) had venous complications and 18 limbs (2%) had arterial sequelae. Following supraclavicular scalenectomy and rib resection, an excellent response was achieved in 59% (455 cases) and a good result was achieved in another 27% (206 cases). A fair outcome was present in 13% (95 cases) and a poor result was found in only 1% (13 cases). There was a single occurrence of lymphatic leakage and no brachial plexus injuries resulted. Postoperative causalgia requiring subsequent sympathectomy developed in two cases. No vascular or permanent phrenic nerve injuries occured and only 12 patients (2%) required operative intervention for recurrent TOS. First rib resection and scalenectomy can be performed by the supraclavicular route with an acceptable outcome, minimal morbidity, and long-lasting results.

Shoulder-arm pain from cervical bands and scalene muscle anomalies

Fourteen patients were identified with (1) pain and sensory changes in a brachial plexus distribution, (2) aggravation of pain with use of the affected extremity, and (3) pain on palpation over the brachial plexus. All patients had minimal or no intrinsic hand muscle atrophy. Only one patient had cervical ribs. Nerve conduction studies were normal, and electromyography (EMG) showed mild chronic neuropathic changes in 2 patients. None of the patients responded to conservative therapy over a prolonged period (7-12 months). A compressive brachial plexopathy from abnormally attached or enlarged scalene muscles that affected both upper and lower trunks of the brachial plexus was found at surgery in all patients. In 13 patients, at least one fibrous band compressed the lower trunk of the brachial plexus. Therefore, neurogenic thoracic outlet syndrome can occur from cervical bands and scalene muscle anomalies without intrinsic hand muscle atrophy, cervical ribs, enlarged C7 transverse processes, or EMG abnormalities.

The thoracic outlet syndrome

The thoracic outlet syndrome is a compressive neurovascular condition of the upper extremity. The neurologic, arterial, and venous structures may be affected individually or in combination in any given patient. Multiple surgical and medical subspecialists may be involved in the care of these patients, including orthopedic, vascular, and thoracic surgeons, neurosurgeons, and neurologists. The topic is extremely controversial; some authors believe that this is a very common condition, while others question the existence of the syndrome. There is disagreement concerning the diagnosis, workup, and proper therapeutic management. The purpose of this article is to critically review and analyze the literature on this subject.

Neurovascular injuries to the shoulder

The throwing athlete is at risk for neurovascular injuries of the shoulder because of the excessive demands placed upon the shoulder by repetitive throwing motions. The most commonly recognized neurovascular compression syndromes are axillary artery occlusion, effort thrombosis, quadrilateral space syndrome, and thoracic outlet syndrome. Diagnosis is aided by the use of the Adson's test, costoclavicular maneuver, and hyperabduction maneuver. Initial treatment usually is nonoperative. Anticoagulation or thrombolytic therapy can be used for vascular occlusion. Surgery usually is reserved for patients suffering acute or chronic symptoms despite nonoperative treatment. With proper treatment, most patients are able to resume their previous athletic activities in a timely manner with minimal disability.

Anatomical mechanisms explaining damage to pacemaker leads, defibrillator leads, and failure of central venous catheters adjacent to the sternoclavicular joint

The literature suggests that approximately 93% of all pacemaker lead fractures occur in the segment of the lead lateral to the venous entry, and costoclavicular compression has been implicated. While blood vessels can be compressed by movements of the clavicle, our research suggests that lead and catheter damage in that region is caused by soft tissue entrapment rather than bony contact. Dissection of eight cadavers with ten leads revealed that two entered the cephalic vein, and were not included in the study. Of the other eight leads, four passed through the subclavius muscle, two through the costoclavicular ligament, and two through both these structures before entering the subclavian, internal jugular, or brachiocephalic vein. Anatomical studies demonstrated that entrapment by the subclavius muscle or the costoclavicular ligament could cause repeated flexing of leads during movements of the pectoral girdle. Cineradiology of patients with position dependent catheter occlusion confirmed entrapment by the subclavius muscle. Soft tissue entrapment imposes a static load upon leads and catheters, and repeated flexure about the point of entrapment may be responsible for damage previously attributed to cyclic costoclavicular compression.

Long term outcome after resection of the first rib for thoracic outlet syndrome

A total of 112 first ribs in 103 patients were resected over 11 years for thoracic outlet syndrome. Seventy-seven patients (84 operations) were followed up for 2.5 years or more to assess the long term results of this procedure and the factors affecting them. One month after surgery 52 per cent of limbs were asymptomatic and 77 per cent were at least improved. A follow-up examination was performed, on average 6.1 years after the operation, by two independent examiners. This evaluation showed a permanent success rate of 37 per cent among 84 limbs examined. These long term results compare unfavourably with previously published data. The reason for the poor final outcome seemed to be difficulty in selecting patients for the operation. This was not aided by any of the preoperative tests. Patients in this study were evaluated by independent examiners, and only a total absence of preceding symptoms was accepted as the criterion for success. We emphasize the importance of unbiased evaluation and long term follow-up.