![]() ![]() Note that the location is several centimeters proximal to the extensor retinaculum and radiocarpal joint. 4,5Īnatomic diagram showing the intersection between the APL, EPB, ECRB and ECRL. ![]() Marking the area of symptoms can be useful to ensure imaging of the correct anatomic region. ![]() Additional images of the forearm may be needed to evaluate this region if the clinician orders a wrist examination. 17,18īecause the crossover is located on average 4 cm proximal to the radiocarpal joint, most standard wrist MRI protocols will not include the intersection. 4,5,16 This intersection creates a mechanically disadvantageous arrangement where thumb and wrist motion results in friction between the crossing tendons. The first compartment tendons cross over the second compartment tendons in the radial dorsal forearm, approximately 4 cm proximal to Lister’s tubercle. The extensor carpi radialis brevis and longus originate at the lateral humeral epicondyle, and course in the second dorsal extensor tendon compartment toward their metacarpal insertions. The tendons course in the first dorsal extensor tendon compartment toward their insertions on the thumb. The abductor pollicis longus and extensor pollicis brevis muscles originate from the posterior radius and interosseous membrane. Severe cases can lead to complications such as tendon rupture or stenosing tenosynovitis, which may require surgical intervention. 13 Severity is also variable, with most cases being mild and responsive to conservative treatment. 2,10 Other patients have harvested rice with hand tools for weeks before reporting symptoms. 12,13 Onset and tempo of the disorder is highly variable, with some patients presenting after a single ski run or a brief episode of activity. 9,10,11 Patients working with agricultural or digging tools have been specifically reported in the literature, along with carpenters, secretaries, and supermarket checkout clerks. Athletes performing rowing, weightlifting, skiing and racquet sports are frequently seen. Most patients report activities involving repetitive flexion and extension of the wrist. 7 The exact etiology is still unclear, and may be multifactorial. suggested that the extensor fascia of the forearm may also contribute to stenosis of the tendon compartments in this region. Surgical release of only the second extensor compartment resulted in relief of symptoms in their series. proposed stenosis of the second extensor compartment as the underlying primary abnormality, with secondary inflammation and involvement of the adjacent first compartment tendons. The etiology was originally thought to be due to mechanical friction between the two tendon compartments. The main abnormality is noninfectious peritendinous inflammation in the first and second dorsal extensor tendon compartments around their site of intersection, located 4 to 8 cm proximal to Lister’s tubercle. 1 This entity has been known by numerous other names, including “crossover syndrome” or “APL syndrome” for its anatomic location, “peritendinitis crepitans” or “squeaker’s wrist” due to audible crepitus in some patients, “oarsmen’s wrist” or “Bugaboo forearm” from associated activities, and “subcutaneous perimyositis” as a description of the pathology. Diagnosisįlexor hallucis longus tenosynovitis at the knot of Henry.Īll three cases can be categorized as tendon intersection syndromes.įorearm pain and swelling at the junction of the first and second dorsal extensor tendon compartments due to overuse was first described by Velpeau in 1841, and subsequently termed “intersection syndrome” by Dobyns et al. The axial fat suppressed fast spin-echo proton density-weighted image through the midfoot showing fluid intensity signal around the flexor hallucis longus tendon (FHL). ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |