Two-stage exchange arthroplasty is traditionally used to treat periprosthetic hip infection. Nevertheless, particularly in high-risk patients, there has been increased attention towards alternatives such as 1.5-stage exchange arthroplasty which takes place in one surgery. Therefore, we sought to compare (1) operative time, length-of-stay (LOS), transfusions, (2) causative organism identification and polymicrobial infection rates, (3) re-revision rates and re-revision reasons, (4) mortality, and determine (5) independent predictors of re-revision.

Retrospective chart review of 71 patients who underwent either 1.5- (n=38) or 2-stage (n=33) exchange hip arthroplasty at a single institution (03/2019-05/2023). Demographics, surgical, inpatient, and infection characteristics were noted. Main outcomes evaluated were re-revision rates, re-revision reasons, mortality, and cause of death. Independent predictors of re-revision were assessed utilizing logistic regression. Mean follow: 675 days (range, 23–1,715).

Demographics were not significantly different except for a higher proportion of 1.5-stage patients classified as American-Society-of-Anesthesiologists (ASA) status 3 or 4 (84.2 vs. 48.5%, p=0.002). Length of follow-up was significantly longer in the 2-stage group (924.4 vs. 458 days, p<0.001) as well as operative time (506 vs. 271 minutes, p<0.001). In the 1.5-stage group, there was a higher proportion of polymicrobial infections (23.7 vs. 3.0%, p=0.016), re-revision rates (28.9 vs. 9.1%, p=0.042) and periprosthetic infections as a cause of revision (90.9 vs. 0%, p=0.007). Mortality rates were not significantly different, and no patient died for causes related to infection. Type of surgery (1.5-stage vs. 2-stage) was the only independent predictor of re-revision (odds-ratio 4.0, 95% confidence-interval 1.02–16.16, p=0.046).

Our data suggests that patients who undergo 1.5-stage exchange arthroplasty have a significantly higher re-revision rate (mostly due to infection) when compared to 2-stage patients. We acknowledge potential benefits of the 1.5-stage strategy, especially in high-risk patients since it involves single surgery. However, higher re-revision rates must be considered when counseling patients.

Osteolysis, fractures, and bone destruction caused by osteomyelitis or metastasis can cause large bone defects and present major challenges during acetabular reconstruction in total hip arthroplasty. We sought to evaluate the survivorship and radiographic outcomes of an acetabular reconstruction consisting of a polyethylene liner (semi-constrained) embedded in cement filling bone defect(s) reinforced with screws and/or plates for enhanced fixation (HiRISC).

Retrospective chart review of 59 consecutive acetabular reconstructions as described above performed by 4 surgeons in a single institution (10/18/2018-1/5/2023) was performed. After radiographs and operative reports were reviewed, cases were classified following the Paprosky classification for acetabular defects. Paprosky type 1 cases (n=26) were excluded, while types 2/3 (n=33) were included for analysis. Radiographic loosening was evaluated up to latest follow-up. Mean follow-up was: 487 days (range, 20–1,539 days).

Out of 33 cases, 2 (6.1%) cases were oncological (metastatic disease) and 22 (66.7%) had deep infection diagnosis (i.e., periprosthetic joint infection [PJI] or septic arthritis). In total, 7 (21.2%) reconstructions were performed on native acetabula (3 septic, 4 aseptic). At a mean follow-up of 1.3 years, 5 (15.2%) constructs were revised: 4 due to uncontrolled infection (spacer exchange) and 1 for instability. On follow-up radiographs, only 1 non-revised construct showed increased radiolucencies, but no obvious loosening. When compared to patients with non-revised constructs, those who underwent revision (n=5) were significantly younger (mean 73.8 vs. 60.6 years, p=0.040) and had higher body mass index (24.1 vs. 31.0 Kg/m², p=0.045), respectively. Sex, race, ethnicity, American-Society-of-Anesthesiologist classification, infection diagnosis status (septic/aseptic), and mean follow-up (449.3 vs. 695.6 days, respectively, p=0.189) were not significantly different between both groups.

HiRISC construct may be a viable short-term alternative to more expensive implants to treat large acetabular defects, particularly in the setting of PJI. Longer follow up is needed to establish long term survivorship.