Abstract
Introduction
The evaluation of treatment modalities for distal femur periprosthetic fractures (DFPF) post-total knee arthroplasty (TKA) has predominantly focused on functional and radiological outcomes in existing literature. This study aimed to comprehensively compare the functional and radiological efficacy of locking plate (LP) and retrograde intramedullary nail (IMN) treatments, while incorporating mortality rates.
Method
Twenty patients (15 female, 5 male) with a minimum 24-month follow-up period, experiencing Lewis-Rorabeck type-2 DFPF after TKA were included. These patients underwent either LP (n=10) or IMN (n=10). The average follow-up duration was 48 months (range: 24–192). Treatment outcomes, including functional scores, alignment, union time, complications, and mortality rates, were assessed and compared between LP and IMN groups. Clinical examination findings pre-treatment and at final follow-up, along with two-way plain radiographs, were utilized. Statistical analyses comprised Student's t-test and Kaplan-Meier survival analysis with a 95% confidence interval.
Result
At final follow-up, the LP group demonstrated a mean Knee Society score of 67.2 ± 16.1, while the IMN group exhibited a score of 72.8 ± 9.4(P = 0.58). No statistically significant differences were observed in alignment between the groups[aLDFA (anatomical lateral distal femoral angle), P = 0.31; aPDFA (anatomical posterior distal femoral angle), P = 0.73]. The mean time to union was 3.7 ± 0.8 months for LP and 3.9 ± 0.6 months for IMN (P = 0.62). Complications such as infection occurred in 1 LP patient, and non-union was observed in 2 LP patients, while no complications were noted in IMN group(P < 0.01). Mortality rates were notably lower in the IMN group compared to the LP group across various time intervals.
Conclusion
Both LP and IMN treatments yielded similar functional scores, alignment, and union time for DFPF post-TKA. However, the lower incidence of complications and mortality rates associated with IMN treatment suggest its superiority in managing DFPF following TKA.
