Session I - Polytrauma / Pelvis / Post-Traumatic Reconstruction

Thurs., 10/10/13 Polytrauma/Pelvis/Post-Trauma, PAPER #34, 4:06 pm OTA 2013

Acute Total Hip Arthroplasty Versus Open Reduction and Internal Fixation for Acetabular Fractures Involving the Posterior Wall in Patients <65 Years Old: A Matched Cohort Analysis

Carol A. Lin, MD, MA; Jerald Westberg, BA; Andrew H. Schmidt, MD;
Hennepin County Medical Center, Minneapolis, Minnesota, USA

Purpose: Acute total hip arthroplasty (THA) has been advocated for acetabular fractures in elderly patients; however, its usage in younger patients with fractures at high risk for reoperation, such as those involving the posterior wall, has rarely been studied. We hypothesized that patients <65 years old who underwent acute THA would have lower rates of reoperation and similar functional outcomes compared those underwent open reduction and internal fixation (ORIF).

Methods: We retrospectively reviewed consecutive patients under the age of 65 with acetabular fractures involving the posterior wall (62A1, 62A2 + posterior wall, 62B1 + posterior wall) treated at a Level I trauma center from 1996 to 2011. Operatively treated patients were grouped by acute THA or ORIF and were matched by fracture pattern and age at a 2:1 ratio within blocks of 5 years. Patients without a minimum of 1-year follow-up were excluded. The modified Oxford Hip Score* was used to assess functional outcome. Rates of reoperation and referral for THA were recorded. A P <0.05 was considered significant.

Results: 16 THA patients and 32 ORIF patients were evaluated at an average follow-up of 6.2 years (range, 1-15.2) with an average age of 56.4 versus 54.3 years (P = 0.163). There was no difference in the proportion of high-energy mechanisms of injury (100% vs 75%, P = 0.154) or ISS (11.7 vs 13.5, P p = 0.525). There were significant differences in the rates of marginal impaction (94% THA vs 41% ORIF, p < 0.001), full thickness cartilage injury to the femoral head (69% THA v 19% ORIF, P = 0.001), and involvement of the weight-bearing dome (44% THA vs 13% ORIF, P = 0.027). At last follow-up, 12 hips (37.5%) in the ORIF group had undergone THA or been referred for THA; 75% of these occurred within 1 year, and 83% were within 2 years. This was compared to 2 revisions (12.5%, P = 0.312) in the THA group: one loose cup at 2 months and one infection at 14 years. There was no difference in surgical time, blood loss, or the number of postoperative complications. The average time to full weight bearing was 98 days in the ORIF group compared to 71 days in the acute THA group (P = 0.045). The average Oxford Hip Score in the acute THA group was 44 compared to 40 in the ORIF group (P = 0.048) and there was no difference in the number of good-excellent results (93% vs 85%, P = 0.636).

Conclusion: Both ORIF and acute THA for high-energy acetabular fractures involving the posterior wall in middle-aged patients can provide excellent results. Acute THA may be more appropriate for those with femoral head involvement, articular comminution, or marginal impaction. Acute THA patients had better functional scores and earlier weight bearing. The indications for and utility of acute THA in this group warrant further investigation.

*Oxford Hip Score: range 0-48; >41 = excellent, 34-41 = good, 27-33 = fair, <27 = poor.

Alphabetical Disclosure Listing

• The FDA has not cleared this drug and/or medical device for the use described in this presentation   (i.e., the drug or medical device is being discussed for an “off label” use).  ◆FDA information not available at time of printing. Δ OTA Grant.