Achieving joint stability can be challenging in 1.5-stage exchange arthroplasty for periprosthetic joint infection (PJI) when substantial bone defects are present. Cement augmentation has been used to address these defects for stability, yet evidence regarding its mechanical durability and survivorship remains limited. This study aimed to compare the aseptic survival between 1.5-stage exchange arthroplasty with and without cement augmentation using an autoclaved original femoral component and a new polyethylene (PE) insert.

There would not be significant inferior survival in 1.5-stage exchange arthroplasty with cement augmentation compared with arthroplasty without cement augmentation.

This retrospective comparative study reviewed 130 cases of 1.5-stage exchange arthroplasty without reinfection, comprising 42 cases with cement augmentation (Group C) and 88 cases without cement augmentation (Group N). The cement augmentation technique was used when joint stability could not be achieved using the thickest PE because of severe bone loss. Demographics were not significantly different between the groups. The hip-knee-ankle angle (HKA) and component positions were measured; the proportions of appropriate HKA and component positions (HKA≤0 ± 3°, α≤95 ± 3°, β≤90 ± 3°, γ≤3 ± 3°, and δ≤87 ± 3°) were investigated. Survival and failure rates were analyzed, and failure was defined as reoperation for aseptic failure. Risk factors affecting survival were investigated in terms of demographics, cement augmentation, inappropriate HKA, and inappropriate component position for all patients in both groups.

Although the average HKA and component positions were not different, appropriate proportion of coronal and sagittal PE position were significantly lower in the group C (appropriate β, 57.1% vs 90.9%; appropriate δ, 38.1% vs 77.3%; p < 0.001, respectively). All cases with aseptic loosening underwent reoperation. The 1-, 2-, and 5-year survival rates were 76.2%, 71.4%, and 71.4%, respectively, in group C and 89.8 %, 86.4 %, and 81.6 %, respectively, in group N ( p = 0.063). The failure rates were 28.6% and 18.2% in group N, respectively ( p = 0.253). The significant factor affecting the survival was only the inappropriate coronal positioning of the PE (β > 90 ± 3°) in overall cases (odds ratio = 2.957, p = 0.016).

Cement augmentation can be employed as a salvage-enabling technique to address bone loss and instability in 1.5-stage exchange arthroplasty, showing no significant inferiority in aseptic survival despite a trend toward lower survival. Meticulous attention to coronal PE alignment during cement hardening is essential to minimize the risk of aseptic failure.

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