| Introduction |
 A compressive neuropathy of the median nerve at the level of the elbow- Epidemiology
- more common in women
- common in 5th decade
- has been associated with well-developed forearm muscles (e.g. weight lifters)
- Pathoanatomy
- 5 potential sites of entrapment include
- supracondylar process
- residual osseous structure on distal humerus present in 1% of population
- ligament of Struthers
- travels from tip of supracondylar process to medial epicondyle
- not to be confused with arcade of Struthers which is a site of ulnar compression neuropathy in cubital tunnel syndrome
- bicipital aponeurosis (a.k.a. lacertus fibrosus)
- between ulnar and humeral heads of pronator teres
- FDS aponeurotic arch
- Associated conditions
- commonly associated with medial epicondylitis
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| Presentation |
- Symptoms
- paresthesias in thumb, index, middle finger and radial half of ring finger as seen in carpal tunnel syndrome
- in pronator syndrome paresthesias often made worse with repetitive pronosupination
- should have characteristics differentiating from carpal tunnel syndrome (CTS)
- aching pain over proximal volar forearm
- sensory disturbances over the distribution of palmar cutaneous branch of the median nerve (palm of hand) which arises 4 to 5 cm proximal to carpal tunnel
- lack of night symptoms
- Physical exam
- provocative tests are specific for different sites of entrapment
- positive Tinel sign in the proximal anterior forearm but no Tinel sign at wrist nor provocative symptoms with wrist flexion as would be seen in CTS
- resisted elbow flexion with forearm supination (compression at bicipital aponeurosis)
- resisted forearm pronation with elbow extended (compression at two heads of pronator teres)
- resisted contraction of FDS to middle finger (compression at FDS fibrous arch)
- possible coexisting medial epicondylitis
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| Imaging |
- Radiographs
- recommended views
- elbow films are mandatory
- findings
- may see supracondylar process
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| Studies |
- EMG and NCV
- may be helpful if positive but are usually inconclusive
- may exclude other sites of nerve compression or identify double-crush syndrome
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| Treatment |
- Nonoperative
- rest, splinting, and NSAIDS for 3-6 months
- indications
- mild to moderate symptoms
- technique
- splint should avoid forearm rotation
- Operative
- surgical decompression of median nerve
- indications
- only when nonoperative management fails for 3-6 months
- technique
- decompression of the median nerve at all 5 possible sites of compression
- outcomes
- of surgical decompression are variable
- 80% of patients having relief of symptoms
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