Femoroacetabular impingement predisposes to traumatic posterior hip dislocation

Steppacher, Simon D.; Albers, Christoph E.; Siebenrock, Klaus A.; Tannast, Moritz; Ganz, Reinhold (2013). Femoroacetabular impingement predisposes to traumatic posterior hip dislocation. Clinical orthopaedics and related research, 471(6), pp. 1937-1943. Springer 10.1007/s11999-013-2863-4

Full text not available from this repository. (Request a copy)

BACKGROUND Traumatic posterior hip dislocation in adults is generally understood to be the result of a high-energy trauma. Aside from reduced femoral antetorsion, morphologic risk factors for dislocation are unknown. We previously noticed that some hips with traumatic posterior dislocations had evidence of morphologic features of femoroacetabular impingement (FAI), therefore, we sought to evaluate that possibility more formally. QUESTIONS/PURPOSES We asked whether hips with a traumatic posterior hip dislocation present with (1) a cam-type deformity and/or (2) a retroverted acetabulum. METHODS We retrospectively compared the morphologic features of 53 consecutive hips (53 patients) after traumatic posterior hip dislocation with 85 normal hips (44 patients) based on AP pelvic and crosstable axial radiographs. We measured the axial and the lateral alpha angle for detection of a cam deformity and the crossover sign, ischial spine sign, posterior wall sign, retroversion index, and ratio of anterior to posterior acetabular coverage to describe the acetabular orientation. RESULTS Hips with traumatic posterior traumatic dislocation were more likely to have cam deformities than were normal hips, in that the hips with dislocation had increased axial and lateral alpha angles. Hips with posterior dislocation also were more likely to be retroverted; dislocated hips had a higher prevalence of a positive crossover sign, ischial spine sign, and posterior wall sign, and they had a higher retroversion index and increased ratio of anterior to posterior acetabular coverage. CONCLUSIONS Hips with posterior traumatic dislocation typically present with morphologic features of anterior FAI, including a cam-type deformity and retroverted acetabulum. An explanation for these findings could be that the early interaction between the aspherical femoral head and the prominent acetabular rim acts as a fulcrum, perhaps making these hips more susceptible to traumatic dislocation.

Item Type:

Journal Article (Original Article)

Division/Institute:

04 Faculty of Medicine > Department of Orthopaedic, Plastic and Hand Surgery (DOPH) > Clinic of Orthopaedic Surgery

UniBE Contributor:

Steppacher, Simon Damian; Albers, Christoph; Siebenrock, Klaus-Arno and Tannast, Moritz

Subjects:

600 Technology > 610 Medicine & health

ISSN:

0009-921X

Publisher:

Springer

Language:

English

Submitter:

Stephanie Schmutz

Date Deposited:

04 Apr 2014 11:18

Last Modified:

04 Apr 2014 11:18

Publisher DOI:

10.1007/s11999-013-2863-4

PubMed ID:

23423625

URI:

https://boris.unibe.ch/id/eprint/42680

Actions (login required)

Edit item Edit item
Provide Feedback