NEW Research: Deep Hip Sockets (Coxa Profunda) Not Enough Diagnose Pincer Hip Impingement - Especially in Women

Coxa profunda means that your hip (acetabular) socket is deep. Until recently, findings of coxa profunda on x-rays have been considered indicative of pincer-type femoroacetabular impingement. A study presented in the American Journal of Bone and Joint Surgery hypothesized that coxa profunda is a very common radiographic finding in females and is not a finding that is specifically associated with pincer-type femoroacetabular impingement. 


The researchers divided study objects into four groups of hips: those with acetabular dysplasia (fifty-eight hips), femoroacetabular impingement (fifty hips), symptomatic residual Legg-Calvé-Perthes deformities (sixteen hips), and asymptomatic hips (thirty-three). Coxa profunda was present when the floor of the acetabular fossa touched or was medial to the ilioischial line. The association between coxa profunda and hip disorder diagnosis, lateral center-edge angle, acetabular inclination, patient age, and sex was analyzed.

Coxa Profunda

Coxaprofunda was seen in 55% of the 157 hips and was slightly less com mon in the hips with acetabular dysplasia or residual Legg-Calvé-Perthes deformities (41% and 31%, respectively). Coxa profunda was evident in 76% of the thirty-three asymptomatic hips compared with 64% of the fifty hips with femoroacetabular impingement.

Coxa profunda was more common in females than males (70% compared with 24%). Acetabular overcoverage (a lateral center-edge angle of >40° or acetabular inclination of <0°) was seen in only 22% of hips with coxa profunda.

The researchers concluded that coxa profunda should be considered a normal radiographic finding, at least in females. They went on to say that coxa profunda is a nonspecific radiographic finding, seen in a variety of hip disorders and asymptomatic hips. The presence of deep sockets is neither necessary nor sufficient to support a diagnosis of pincer-type femoroacetabular impingement.

Sources: 

J Bone Joint Surg Am, 2013 Mar 06;95(5):417-423
Coxa Profunda Is Not a Useful Radiographic Parameter for Diagnosing Pincer-Type Femoroacetabular  Impingement. Jeffrey J. Nepple, MD1; Charles L. Lehmann, MD1; James R. Ross, MD1; Perry L. Schoenecker, MD1; John C. Clohisy, MD1 
1 Department of Orthopaedic Surgery, Washington University School of Medicine.

Image from: 
http://www.orthopaedicsone.com/download/attachments/1999227/Profunda.jpg