Acetabular fractures are debilitating injuries with treatment and morbidity profiles largely associated with classification schema described by Judet and Letournel. Patterns often exist outside this schema however including an Associated Both-Column acetabular fracture (ABCAF, OTA/AO 62C) with a concomitant Posterior Wall (PW) fracture. This fracture pattern is thought to create significant hip instability; however, little investigation has been done to determine outcomes following surgical repair of these injuries in comparison to ABCAFs with no PW involvement.
The objective of this study was to compare ABCAF injuries with and without PW involvement primarily regarding subsequent conversion to total hip arthroplasty (THA) to determine if PW involvement is an indicator for poor outcomes.
Design and Methods
This review utilized study groups determined from a database of all 72 ABCAFs in 72 patients treated with open reduction and internal fixation between 2010 and 2017 at two Level I trauma centers. The presence of an ipsilateral PW fracture was determined radiographically yielding a control group (-PW) of 47 patients and a study group (+PW) of 25 patients. 26 (59%) control and 18 (41%) study patients were included for final analysis through achievement of 12-months of follow up and/or subsequent conversion to a THA. Patients who received a THA as their index procedure (n=5) were excluded. Demographic, injury, treatment, and post-operative course information was collected retrospectively via a chart review for these patients. Unpaired t-tests were used to compare study and control groups across all factors. A Kaplan-Meier curve was applied to compare survivorship of control and study groups.
Of the 44 patients included, 7 (15.9%) received a subsequent THA although no difference in the rate of conversion between study (n=4, 22.2%) and control (n=3, 11.1%) groups was seen (p=0.42). Results from the Kaplan-Meier curve also indicated no difference in survivorship between study groups (p=0.35).
No differences between groups were observed across other treatment and post-operative outcomes, including length of surgery (p=0.57), complication rate (p=0.76), and post-operative pain (p=0.14). It should be noted that complication rates were high overall for both study groups, with 7 (38.9%) +PW and 8 (30.1%) -PW patients experiencing a complication. The average age of all included patients was 50.5 years, with no difference between groups (p=0.51). No differences in % male (p=1.00), average Charlson Comorbidity Index (p=0.98), or mechanism of injury (p=0.72) were observed.
ABCAFs with PW involvement do not appear to confer worse clinical outcomes for patients than those without especially as it relates to ipsilateral joint replacement. This information should aid in treatment planning following these injuries.