Discussion

Given that TOS is a rare condition (1-3 in 100,000) and a clinical diagnosis of exclusion, identifying cases with heterogenous, nonspecific symptoms can prove challenging. The diagnosis is further complicated by substantial symptom overlap with similar and commonly comorbid conditions such as cervical radiculopathy,2, 3, 4 as was seen in our patient. Patients who perform repeated arm and shoulder movements through work, weightlifting, and athletics are at an increased risk for developing TOS due to hypertrophy of the scalene muscles,1, 2, 3, 4 and baseball pitchers have been a population uniquely identified as high risk for the development of TOS.1,4,5,7

Nonoperative management with PT focusing on reducing tensile or compressive loads across the thoracic outlet region and behavioral modifications are the initial therapy of choice1, 2, 3, 4,7,8 and is successful in up to 70% of patients with neurogenic TOS.7,8 Should conservative therapy fail, a local injection of botulinum toxin, local anesthetic, or steroids into the anterior scalene are used.4 Relief of symptoms, particularly by lidocaine block, predicts the likelihood of successful resolution of symptoms following surgical intervention.1,2,4,9,10 Surgical interventions include surgical resection of the first rib or the scalene muscles,1, 2, 3,7,8,11,12 and studies have shown success rates as high as 90% in symptomatic improvement following surgery.12,13 Smaller studies have evaluated the roles of PT, botulinum injections, and surgery in collegiate and professional athletes.5,14 Most experience relief of symptoms and return to play with conservative measures, and those who do require surgery have excellent outcomes with nearly all returning to play within 1 year.15, 16, 17

Brain fog as a possible symptom of TOS had not appeared in the literature before 2025 when a case report was published highlighting the resolution of long standing, nonspecific cognitive “fog” following surgical correction of TOS in a patient in Maryland.18 Similarly, our patient experienced rapid resolution of his persistent brain fog following surgical correction of his TOS. It is known that cervical degenerative disease and sleep disturbance are related,19 though our report highlights that there may be a link between thoracic outlet compression and nonspecific cognitive dysfunction. Yin et al19 proposed that the neurovascular compression and chronic painful stimuli in TOS could contribute to increased sympathetic reactivity and increased intercranial pressure both leading to poor sleep and autonomic dysfunction. This pathophysiology could be responsible for the clinical symptoms of “brain fog,” although a direct causal mechanism remains uncertain. Additional research is required to better understand this phenomenon.