The upper thoracic spine is considered the stiffest part of the thoracic spine. Pain is j usually well localized but may cause distal symptoms. Probably via the autonomic nervous system. A specific syndrome in this region is known with a hypomobility lesion at the T4 level and has the following features:
- Arm pain or vague discomfort in the arm associated with paresthesias that do not follow any dermatome patten, with the hand always involved.
- Diffuse posterior head and neck pain in some patients.
- Hypomobility at one or more levels (T3-T4, T4-T5, or T5-T6); t4 is invariably involved.
- Tenderness and stiffness, especially at T3-T4 and T4-T5.
The mechanism is unknown, but an associated disturbance of autonomic nerve control has been postulated. Predisposing factors have been attributed to unaccustomed lifting, stretching, pushing activities, or trauma (e.g., a motor vehicle accident, a fall). A replaced posture, with forward head, accentuated thoracic kyphosis, and protracted shoulder girdle, may predispose the patient to this syndrome.
Butler has explained the symptom distribution and the apparent epiphenomena of symptomatic involvement based on the clinical observation made by patients with the symptom complex have positive upper limb tension test ans some have a positive slump test. The T4 to T9 segment of the spinal canal is a narrow zone where minimal reduction in the size of the canal will result in possible compromise of the neuraxis and the meninges. With injury to surrounding joints, a site of adverse tension may be initiated. Other structures such as the thoracic sympathetic trunk ans ganglia, dura mater, nerve toots, and even the preganglionic neurons in the cord may eventually be irritated.
Articulation and mobilization of the involved area always relieve symptoms after 3 to 4 treatments.
If the relaxed posture is considered a predisposing factor, postural correction exercises can be useful.( ask your therapist for more specific exercise). (Corrigan and Maitland, MaGuckin and Klapp)