1 / 50

Nerve Compression Syndromes

Nerve Compression Syndromes. Gavin O’Mahony, MD. Objectives. To understand the cause and natural history of NCSs To understand the diagnosis and work up of NCSs To review operative and non-operative treatment modalities. Pathophysiology of Chronic Nerve Compression.

ursa
Download Presentation

Nerve Compression Syndromes

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Nerve Compression Syndromes Gavin O’Mahony, MD

  2. Objectives • To understand the cause and natural history of NCSs • To understand the diagnosis and work up of NCSs • To review operative and non-operative treatment modalities

  3. Pathophysiology of Chronic Nerve Compression • Compression causes ischemic neuropathy • Continuum of neural changes depend on the force and duration of compression

  4. Neural changes do not occur uniformly across the nerve • Vary depending on the distribution of compressive forces • Superficial fascicles undergo changes sooner • Result in varying patient symptoms within a single nerve distribution • Example: Early Carpal tunnel • Superficial fascicles to the long and ring fingers • More central fascicles to the thumb and radial side of • The index finger

  5. Systemic Conditions and Personal Factors • Diabetes Mellitus • Hypothyroidism • Excessive alcohol use • Obesity • Tobacco use • Occupational Factors • Certain postures and positions may contribute to nerve compression • Positions of moderate flexion and extension increase pressure in the carpal tunnel • Elbow flexion increases pressure in cubital tunnel • Relationship accepted by workers compensation agencies

  6. Median nerve • Carpal Tunnel Syndrome • Pronator Syndrome • Anterior Interosseous Syndrome

  7. Carpal Tunnel

  8. Carpal Tunnel Syndrome • Compression of the Median n. at the wrist • Most common nerve compression in UE • Paresthesia, numbness or bothin the median nerve distribution

  9. Aching in the thenar eminence • Weakness of APB and OP (Palmar abduction) • Clinical diagnosisbased on a combination of • Symptoms and characteristic physical findings

  10. Provocative tests • Phalen’s test

  11. Durkan’s test

  12. Tinel’s test

  13. Electrodiagnostic studies can be useful to confirm diagnosis in equivocal cases • NCS can also stage the degree of nerve degeneration • Limitations of NCS – it evaluates only large myelinated fibers • Includes motor axons and sensory axons relaying vibration and light touch • Does not include smaller axons conveying pain or temperature sensation • Does not detect dynamic changes in blood flow that produce intermittent alterations. • Dependent on expertise of the examiner

  14. Non-Operative treatment • Wrist splinting • Most prefabricated splints position the wrist in 30 degrees of extension • This increased carpal canal pressure • Wrist splints are most effective in neutral position – this makes it difficult to perform normal daily activity • Most providers recommend splinting only at night in neutral position

  15. Non-Operative Treatment Corticosteroid injections – temporary relief is an excellent prognostic factor for successful carpal tunnel surgery Not indicated routinely – temporary relief with finite risk of nerve injury Nerve gliding exercises - avoidance of surgery in up to 80% of patients with mild or moderate compression Anaerobic exercise program – has been shown in one study to produce improvement in median nerve function

  16. Operative treatment • Transverse carpal ligament release • Classic (standard) approach • Two-portal Endoscopic Technique • Single Portal Endoscopic Technique • Mini-open approach

  17. Pronator Syndrome • Compression of the Median n. in the forearm • Between the 2 heads of the Pronator Teres • Much less common than CTS • Linked to repetitive upper extremity activity

  18. Aching pain in the proximal volar forearm • Paresthesias radiating into the thumb, IF, MF and radial ½ of the RF • Similar to CTS • Palmar Cutaneous br. arises 4 cm above the wrist • Decreased sensation over the thenar eminence suggests a more proximal lesion • Provocative tests for CTS negative

  19. Provocative tests • Resisted forearm pronation • Resisted elbow flexion with forearm supinated • Resisted flexion of the MF FDS • Pressure over the leading edge of the pronator teres with the forearm in maximum supination and the wrist in neutral produces paresthesias in the median sensory distribution. • NCS usually negative – useful to exclude other sites of compression

  20. Treatment • Surgery usually not necessary • Activity modification, rest • NSAIDS, Corticosteroids • Conservative management effective in 50-70% • Surgery if space-occupying lesion or if several-month course of nonsurgical treatment fails. • Surgery success rate 90%

  21. X-ray of the distal humerus may show a supracondylar process • Compression by anomalous ligament of Struthers

  22. Anterior Interosseous Nerve Syndrome • Weakness or motor loss of: • Flexor Pollicis Longus • FDP to the IF (and occasionally the MF) • Pronator Quadratus

  23. Weakness or motor loss usually occur spontaneously • Patient may describe clumsiness with fine motor skills such as writing and pinching. • AIN does not innervate the skin – no sensory loss • Pain may be present in the forearm along the course of the nerve

  24. Electrodiagnostic studies are an important part of the workup • Can rule out more proximal lesions and distinguish AIN Syndrome from flexor tendon rupture • Nonsurgical treatment • Rest, splinting and observation for several months • Most improve without surgical intervention • Surgical decompression for patients who fail a several-month course of nonsurgical treatment

  25. Operative treatment • Decompression of the median nerve in the forearm is the same for pronator syndrome and compression of the AIN • All potential compressive sites are released

  26. Ulnar Nerve • Cubital Tunnel Syndrome • Guyon’s Canal

  27. Cubital Tunnel Syndrome • Second most common compression syndrome • Also a clinical diagnosis • Electrodiagnostic testing frequently negative – good for staging • Numbness in the ring and small finger • Aching in the medial aspect of the elbow and forearm

  28. Tinel’s sign positive at or proximal to Cubital Tunnel • Elbow flexion test • Elbow flexion combined with digital pressure

  29. Clawing of the small and ring fingers

  30. Fromentsign

  31. Wartenberg sign

  32. Interosseous wasting

  33. Non-Operative treatment • Avoid positioning that combines elbow flexion with pressure over the ulnar nerve • Driving, phoning, during sleep • Nerve gliding exercises • Static night splinting in extension • Rigid splints often ineffective due to discomfort and noncompliance • 24 hour use of soft elbow pads to protect the ulnar nerve from direct compression

  34. Mild Cuts can often be managed successfully with 2-4 months of non-operative treatment • If this is unsuccessful or if severe on presentation surgery is usually required • In Situ Decompression • Anterior Subcutaneous transposition • Anterior Subfascial/Submuscular transposition • Medial epicondylectomy • Outcomes tend to be less predictable than for Carpal tunnel • 75% with unilateral decompression report improvement • 68% with bilateral decompression report improvement

  35. Compression of Guyon’s Canal

  36. Nerve can be compressed: • Proximal to it’s bifurcation - motor and sensory deficits • Along the course of the deep motor branch – motor deficits only • Along superficial sensory branch – sensory deficits only

  37. Often caused by space occupying lesion in the canal • Ganglions, thrombosis, pseudoaneurysms • Hamate hook nonunion • Anomalous muscles • Pre op imaging studies and electrodiagnostic studies are helpful • Non-operative treatment is recommended with acute cases of localized closed trauma • Wrist splint in neutral

  38. Radial Nerve • SRN compression • PIN Syndrome • Radial Tunnel Syndrome

  39. Posterior Interosseous Nerve Syndrome • Muscles innervated by PIN are affected: • ECRB, Supinator, ECU, EDC, EDQ, EIP, APL, EPL, EPB • May occur after trauma or may have insidious onset

  40. Present with dropped fingers and thumb • Even with complete PIN palsy function of the ECRL (wrist extension) is preserved • Partial lesions are more common • MRI may reveal a mass causing the compression – Lipoma, ganglia • Nerve conduction studies can be useful – EMG detects motor dysfunction • Therapeutic approach identical to RTS – same nerve affected

  41. Radial Tunnel Syndrome • Symptoms of pain and weakness after activities of forceful elbow extension and forearm pronation • Pain typically localizes to the lateral aspect of the forearm • Weakness is often secondary to the pain • May occur simultaneously with lateral epicondylitis • The tendinous origin of the ECRB can be involved in both conditions

  42. Radial tunnel begins anterior to the radiocapitellar joint • Approximately 5cm in length • Formed laterally by the ECRL and BR • Medially by the biceps tendon and brachialis • Posteriorly by the radiocapitellar joint capsule • The BR passes over the nerve in a lateral to anterior direction to form the roof • Ends at the arcade of Frohse

  43. Clinical diagnosis • Most patients have normal NCS • Few objective tests to confirm the presence of RTS • Pain relief after administration of Lidocaine/corticosteroid adjacent to the PIN at the level of the proximal radius is useful in diagnosis

  44. Treatment • Nonsurgical management of both PIN syndrome and RTS is recommended initially • Rest, activity modification, splinting, stretching, anti-inflammatories • Nerve gliding exercises may be useful • In patients with concomitant lateral epicondylitis, tennis elbow straps are not recommended because of the increased pressure on the radial nerve • Surgical decompression after trial of non-operative management

  45. Controversy • Generally described as a nerve compression and entrapment syndrome • Dispute over etiology • Prominent focal tenderness • Normal neurologic function • No confirmatory electrodiagnostic evidence • Symptoms do not occur in the distribution of the affected nerve

  46. Superficial Radial Nerve Compressionaka Wartenberg’s Syndrome • Paresthesia, pain or numbness in the radial sensory nerve distribution

  47. Symptoms are reproduced by forearm pronation and ulnar wrist deviation • Tinel sign over the radial sensory nerve at the point where it exits the deep fascia in the forearm • Nerve conduction studies rarely useful

  48. Treatment • Modify activities to maintain a more supinated position wherever possible • Avoidance of excessive pronosupination • Local corticosteroid injection at the entrapment site between tendons of BR and ECRB are often successful. • Splinting not usually recommended • SRN decompression if non-operative treatment unsuccessful

More Related