ABSTRACT
Objective:To investigate the efficacy of single locked-plate internal fixation combined with autologous iliac bone graft in the treatment of Rorabeck type II periprosthetic distal femural fracture (PDFF) after total knee arthroplasty (TKA).Methods:A retrospective case series study was made on 13 patients suffering from Rorabeck type II PDFF after primary TKA together with severe osteoporosis (T value≤ -2.5 SD) admitted to 940th Hospital of Joint Logistics Support Force of PLA from January 2016 to December 2020, including 4 males and 9 females, aged 65-85 years [(75.2±6.5)years]. All patients were treated with single locked-plate internal fixation combined with autologous iliac bone graft. Anti-osteoporosis and early standardized joint function rehabilitation were undertaken postoperatively. The operation time and intraoperative blood loss were recorded. The range of motion of knee joint was compared before operation, at postoperative 3, 6 and 12 months and at the last follow-up. The Hospital for Special Surgery (HSS) knee score was assessed at postoperative 3, 6 and 12 months and at the last follow-up to evaluate the recovery of knee joint function. The bone mineral density was reexamined at postoperative 6 months and 12 months to evaluate the therapeutic effect of anti-osteoporosis. Complications were detected as well.Results:All patients were followed up for 12-72 months [(43.2±19.9)months]. The operation time was 90-135 minutes [(103.8±12.6)minutes], with the intraoperative blood loss of 100-250 ml [(150.0±45.6)ml]. The range of motion of knee joint was (114.6±7.8)°, (90.4±8.0)°, (97.3±4.8)° and (98.1±6.3)° before operation and at postoperative 3, 6 and 12 months (all P<0.05). The HSS knee score was (80.2±2.2)points, (84.6±2.9)points and (87.3±3.3)points at postoperative 3, 6 and 12 months (all P<0.05). The knee joint function was excellent in 10 patients and good in 3 at postoperative12 months, and the excellent and good rate was 100%. The T value of bone mineral density was (-3.8±0.6)SD, (-3.4±0.6)SD and (-2.9±0.6)SD preoperatively and at postoperative 6 months and 12 months (all P<0.05). One patient experienced nonunion and was cured after secondary autologous iliac bone grafting combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) bone grafting. Three patients developed venous thrombosis of lower limbs and were cured with oral administration of rivaroxaban. One patient had mild knee flexion and extension limitation and was improved after manual release under femoral nerve block anesthesia and subsequent functional rehabilitation. Conclusion:For patients with Rorabeck type II PDFF after TKA, single locked-plate internal fixation combined with autologous iliac bone graft has advantages of short operation time, few intraoperative bleeding, satisfactory knee range of motion and functional recovery as well as significant improvement of bone mineral density.