Research Review: Prevalence of Acetabular Retroversion in Hip Disorders
By Stefanie DiCarrado DPT, PT, NASM CPT & CES
Edited by Brent Brookbush DPT, PT, MS, PES, CES, CSCS, ACSM H/FS
Original Citation: Ezoe, M., Naito, M., Inque, T. (2006). The prevalence of acetabular retroversion among various disorders of the hip. The Journal of Bone and Joint Surgery. 88A (2). 372-379 - ABSTRACT
Why is this relevant?: Structural anomalies such as an increase or decrease in transverse plane acetabular positioning can disrupt normal hip motion. It is important for the clinician to understand not only how a structural anomaly can impact the quality of movement, but the prevalence of these occurrences to avoid "blaming" a person's movement dysfunction on potential structural differences.
Acetabular retroversion means the hip socket is turned more posterior with increased bony coverage of the femur anteriorly.
Study Summary
| Study Design | Retrospective cohort study |
| Level of Evidence | Level III: evidence from non-experimental descriptive study |
| Subject Demographics |
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| Outcome Measures |
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| Results |
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| Conclusions | Individuals with noted developmental orthopedic impairments of the hip joint such as developmental dysplasia and Legg-Calvé-Perthes had higher prevalence of acetabular retroversion than individuals in the healthy control. Given the low prevalence of this particular structural anomaly among healthy controls, it is unlikely that people presenting with lower leg dysfunction (LLD) or lumbo-pelvic hip dysfunction (LPHD) have acetabular retroversion. Individuals with osteoarthritis, however, did have a higher prevalence and so referring a patient or client to an orthopedist may be helpful if exercise does not fully resolve the client/patient's complaints. |
| Conclusions of the Researchers | There is a higher prevalence of acetabular retroversion in those with OA, DYS, and LCP than previously found. The impact on acetabular retroversion on subsequent development of arthritis requires further research. |
Drawing A displays a normal acetabulum; drawing B displays a retroverted acetabulum with a positive cross over sign
Review & Commentary:
This study provides strong evidence to suggest healthy individuals, without a history of orthopedic impairment, have a minor chance of demonstrating acetabular retroversion. Authors used the standard mechanism for determining the orientation of the acetabulum - anteroposterior x-rays, and implemented a standard methodology for obtaining these x-ray images. To eliminate error, the researchers excluded individuals with excessive pelvic tilts - measured by a distance between the pubic symphysis and the sacrococcygeal joint as compared to gender based norms. Additionally, the researchers eliminated any pelvic asymmetry by examining (via x-ray) the positions of the mid point of the sacrum and the pubic symphysis. The authors clearly described the determination criteria for each group and clearly described the methodology for future replication and confirmation of the study's findings.
Using x-ray imaging, the researchers determined acetabular retroversion by looking for cross-over and posterior wall signs (pg 374). A positive cross over sign occurs when a line tracing the anterior rim of the acetabulum crosses over a line tracing the posterior rim of the acetabulum (pg 374). A positive posterior wall sign occurs when the line tracing the posterior rim of the acetabulum is shifted medially to the center of the femoral head -- indicates decreased posterior bony coverage (pg 374).
The main limitation of this study is the non-homogenous sample of subjects. All subjects were of Asian descent; it would be beneficial to repeat with subjects of varying ethnicity.
Anteroposterior Xray showing: Right: positive posterior wall sign Left: positive cross over sign
Why is this study important?
This study is important because it provides information on the prevalence of structural anomalies among individuals with and without pelvis/hip orthopedic impairments. Using this information, human movement professionals can ascertain the likelihood that a person presenting with LPHCD and/or LLD is due to muscle or structural imbalance. The information presented in this study supports the initial use of a corrective exercise strategy in individuals without orthopedic impairment to correct movement dysfunction.
How does it affect practice?
Clinicians should be aware of structural anomalies and check for them if a corrective exercise program does not improve a patient's movement sufficiently. However, clinicians should avoid "blaming" lack of progress on structural make-up without confirming via objective tests.
How does it relate to Brookbush Institute Content?
The low prevalence of structural anomalies suggests that, although one should be aware of the possibility, particularly if the patient plateaus in their program with sufficient exercise progression, a corrective exercise strategy is an appropriate first step for healthy individuals who display LPHCD and/or LLD .
The following videos display a corrective exercise strategy for individuals with LPHCD.
Release: Anterior Thigh SA Active Release
Stretch: Active Hip Flexor Stretch
Mobilize: Hip SA Mobilization
Activate: Glute Activation Circuit
Reactive Integration: Side Stepping Progression
LPHC Integration: Single Leg Touchdown with Anterior to Posterior Pull
© 2015 Brent Brookbush
Questions, comments, and criticisms are welcomed and encouraged -