Differential C8-T1 radiculopathy

C8-T1 root lesion--
C8
Finger extensors, finger flexors, wrist flexors, hand intrinsics
T1
Hand intrinsics



Pancoast-- C8-T1 plus Horner's

Lateral cord-- muscles to forearm and sensation in distribution of median nerve

Medial cord-- all median and ulnar intrinsic muscles weak

Thoracic outlet syndrome- neurogenic, vascular, combined or traumatic. Vascular, that presents with pain, pallor and coolness is uncommon. TOS affects C8,T1 and lower trunk.
Compression may occur from a cervical (C7) rib (seen in 10%), an enlarged C7 transverse process (incomplete rib), a fibrous band (most common) from C7 TP to the clavicle, or fibrotic scalene mucles. The clinical presentation is
mild aching pain of ulnar forearm/hand (66%) without neck pain. Weakness occurs in all hand muscles (ulnar and median – thenar, hypothenar, and interossei). Ulnar (not median) numbness occurs. Hand weakness/clumsiness is prominent. Atrophy (“guttering”) of the lateral thenar eminence (APB) is characteristic. Thenar, hypothenar, and interossei atrophy – Gilliat-Sumner hand. TOS is bilateral in 50%, but less affected side is usually subclinical . No reliable provocative test exists, but 90° abduction + external rotation has best predictive value. Patients may have Tinel’s sign over supraclavicular fossa. Adsons test: turn head back & to affected side & lose radial pulse (for vascular variant) but this sign has been considered mythological (ie rarely present) by some authors.
EMG/NCV: Low APB (median) amplitudes (ulnar amplitudes are normal or slightly low). Low ulnar sensory potentials with normal median sensory potentials. Some say unreliable.
Chest or (oblique) c-spine Xrays or CT to look for C7 TP, cervical rib, etc. Treatment is ???
surgical. Medical treatment, physical therapy is not indicated for true TOS (per Kline)
§ Anterior supraclavicular approach: favored. Incision usually supraclavicular, parallel to clavicle.
§ Posterior subscapular approach: used for morbidly obesity, large cervical ribs, previous anterior surgery. See N10/04.
§ Transaxillary cervical rib resection: favored by vascular surgeons, orthopedists. Per Kline has higher complication rate, less success

Parsonage Turner-- pain then weakness, 90 % recovery within 3 years, affects males predominantly (4:1).

Ulnar neuropathy (see separate entry)