Can TOS or Pectoralis Minor Syndrome Present with Burning Sensation Across Chest and Axillary Region?
Yes, both thoracic outlet syndrome (TOS) and pectoralis minor syndrome can present with burning sensations across the chest and axillary region, as these conditions involve compression of neurovascular structures that can produce neuropathic pain symptoms including burning, paresthesias, and pain radiating through the shoulder, chest, and arm.
Clinical Presentation of Neurogenic Symptoms
The primary symptom pattern in both conditions includes pain in the shoulder and proximal upper extremity with radiation to the neck, chest, and arm, accompanied by paresthesias and numbness in the forearm and hand 1. These neuropathic symptoms arise from compression of the brachial plexus nerves, which accounts for approximately 95% of TOS cases 2.
Specific Symptom Characteristics
Pectoralis minor syndrome specifically causes shoulder, neck, chest, and arm pain, along with paresthesias and weakness in the arm and hand 3. The burning quality of pain is consistent with nerve compression under the pectoralis minor muscle affecting the brachial plexus, axillary artery, and axillary vein 3.
The symptoms of pectoralis minor syndrome closely resemble supraclavicular compression patterns, making the chest and axillary burning sensation a recognized component of the clinical presentation 3.
Neurogenic TOS typically involves compression of the lower trunk of the brachial plexus, which can produce burning dysesthesias along the distribution of affected nerve roots 4.
Anatomical Basis for Chest and Axillary Symptoms
Compression can occur in three distinct anatomical spaces: the interscalene triangle, costoclavicular space, and pectoralis minor space (subpectoral tunnel) 5. The pectoralis minor space is particularly relevant for chest and axillary symptoms given its anatomical location 6.
In one imaging study, the neurovascular bundle was most commonly compressed in the costoclavicular space (mostly positional), but compression in the pectoralis minor space, though rare, was documented 6.
Pectoralis minor compression syndrome occurs in approximately 22.5% of patients treated for TOS, indicating it is a significant contributor to the overall symptom complex 7.
Diagnostic Considerations
Clinical Evaluation Priorities
A detailed history including occupation, daily activities, sports participation, and trauma history is critical for diagnosis, as postural changes with arm elevation or abduction can exacerbate symptoms by narrowing anatomical spaces 3, 5.
Physical examination should specifically assess for tenderness over the pectoralis minor muscle and reproduction of symptoms with arm positioning maneuvers 3.
Imaging and Confirmatory Testing
MRI without IV contrast is sufficient to diagnose neurogenic TOS and can demonstrate compression of neurovascular bundles in the costoclavicular, interscalene, and pectoralis minor spaces 6, 5.
Ultrasound duplex Doppler with dynamic investigation can display arterial and venous compression and show real-time changes during provocative maneuvers 3, 5.
Injection tests (such as anterior scalene blocks or pectoralis minor blocks) are used to confirm the definitive diagnosis 3. Diagnostic botulinum toxin injection into the pectoralis minor muscle can serve both as a diagnostic tool and treatment option 2.
Common Pitfalls to Avoid
Do not overlook concomitant cervical spine pathology (present in 14% of TOS cases) that may mimic or exacerbate symptoms 5. MRI should evaluate for disc protrusions, annular fissures, spinal stenosis, or cord compression 8.
The diagnosis of pectoralis minor syndrome is frequently confused with other upper extremity pain syndromes, requiring systematic evaluation to differentiate between compression sites 3.
Venous compression during arm abduction is commonly seen in both asymptomatic and symptomatic individuals, making clinical correlation with symptoms essential 5. Imaging findings alone without corresponding symptoms should not drive treatment decisions 5.
Underdiagnosis of pectoralis minor compression syndrome may be responsible for incomplete or failed treatment of TOS, as it remains underestimated in clinical practice 7.
Treatment Implications
Conservative treatment with physical therapy for a minimum of 6 weeks is successful in most patients with both TOS and pectoralis minor syndrome 3, 1.
When conservative management fails after 3-6 months, or when there is progressive neurological compromise, surgical intervention should be considered 5.
For pectoralis minor syndrome specifically, tenotomy of the pectoralis minor muscle provides symptom resolution in approximately 79.7% of cases, with low morbidity (4.9% complication rate) 7.