Intersection Syndrome
Intersection syndrome is a tenosynovitis of the second dorsal compartment tendons caused by the "crossover" of the muscle bellies of the first dorsal compartment of the wrist, occurring approximately 2-4 cm proximal to the radial tubercle.
| Intersection Syndrome | |
|---|---|
| Synonym | peritendinitis crepitans, crossover syndrome, adventitial bursitis, subcutaneous perimyositis with abductor pollicis longus syndrome and bugaboo forearm. |
Aetiopathophysiology
Intersection syndrome is an overuse injury caused by repetitive wrist extension.
The affected site is where the muscle bellies of the abductor pollicis longus (APL) and extensor pollicis brevis (EPB) cross over the tendons of extensor carpi radialis longus (ECRL) and extensor carpi radialis brevis (ECRB).
These two compartments intersect at an angle of approximately 60 degrees. One theory is that the syndrome is caused by frictions between the muscle bellies of first compartment cross over the tendons of the second compartment. A second theory is that there is entrapment of muscles in the second compartment secondary to stenosis.
Epidemiology and Risk Factors
In sport-people common culprits are heavy lifting, rowing, and racket sports. The highest risk is when beginning a new sport. The dominant hand is more commonly affected. It can also occur occupationally for example in typists.
Clinical Features
History
The pain is slightly more proximal and dorsal than de quervains. They will typically also report a "squeaking" sensation with wrist and thumb movement.
Examination
Swelling and redness may be noted compared to the contralateral side. More prominent movement of the thumb is required to reproduce the pain in comparison to de quervains. Wrist extension and ulnar deviation may reproduce pain. Squeaking or crepitus may be noted at the site.
Investigations
Ultrasound and/or MRI
Diagnosis
Differential Diagnosis
- De Quervain Syndrome
- Scaphoid fracture
- Osteoarthritis of the first metacarpal joint
- Ganglion cyst
- Wartenderg syndrome
- Sprain
Treatment
Rest, activity modification, bracing, NSAIDs, corticosteroid, surgery. The condition is commonly self-limited.
Follow Up and Prognosis
Summary
References
Literature Review
Literature Review
- Reviews from the last 7 years: review articles, free review articles, systematic reviews, meta-analyses, NCBI Bookshelf
- Articles from all years: PubMed search, Google Scholar search.
- TRIP Database: clinical publications about evidence-based medicine.
- Other Wikis: Radiopaedia, Wikipedia Search, Wikipedia I Feel Lucky, Orthobullets,
