Brachial Plexus Functional Outcomes After Thoracic Outlet Surgery as Measured by the Validated Brachial Assessment Tool.

Background: Thoracic outlet syndrome (TOS) is a condition of neurovascular compression in the cervicoaxillary canal and is commonly divided into neurogenic, venous, and arterial subtypes. Neurogenic TOS, caused by brachial plexus compression, is the most frequent subtype. Diagnosis and management remain challenging. Once diagnosed, conservative treatments are first-line, with surgical decompression reserved for refractory cases. Few validated patient-reported outcomes measures exist specifically for TOS.

Methods: We conducted a prospective case series of 56 surgical decompressions of the thoracic outlet in 46 adults for neurogenic TOS. Patients completed the Brachial Assessment Tool (BrAT) and QuickDASH questionnaires preoperatively and on two separate follow-up appointments postoperatively. Changes in scores were statistically analyzed.

Results: The brachial plexus specific BrAT scores showed significant serial improvements over 12 months following surgery (median BrAT change 18.0 then 31.0; p < 0.05). The familiar but more general QuickDASH scores serial change was -22.73 then -35.23. Strong negative correlations were found between BrAT and QuickDASH score changes (Spearman's rho -0.57 to -0.80; p < 0.05), recognizing that the two measure different constructs.

Conclusion: This study demonstrates the responsiveness and clinical utility of the BrAT for quantifying impairment in TOS. This enables clinicians to establish the severity of the condition in individual patients, as well as assess the impact of interventions by subsequent utilization of the same measure. We propose and recommend the BrAT as an important tool to evaluate brachial plexus specific impairment in the assessment and management of neurogenic thoracic outlet syndrome.