Abstract
OBJECTIVE: Intraoperative femoral condylar avulsion fractures during total knee arthroplasty (TKA) are rare but potentially lead to joint instability and poor outcomes if not properly managed. However, the necessity of using condylar-constrained prostheses in these cases remains controversial. This retrospective study examines the incidence, management approaches, and radiological outcomes of these fractures. METHODS: A total of 47 patients (11 males, 36 females; mean age 67.1 ± 7.0 years) with femoral condylar avulsion fractures were identified from 4290 TKAs performed between January 2008 and December 2022, matched with nonfracture patients at a 1:1 ratio by age, gender, and BMI. Intraoperative fractures were treated using cancellous bone screws or nonabsorbable sutures based on the size of the fracture fragment, without the insertion of condylar constrained prostheses. All patients underwent outpatient follow-up, with data collected on preoperative diagnosis, body mass index (BMI), knee range of motion (ROM), and type of prosthesis used. Key radiological indicators assessed included proximal tibia varus angle (PTVA), distal femoral valgus angle (DFVA), joint line congruence angle (JLCA), hip-knee-ankle angle (HKA), and preoperative subluxation status. RESULTS: The incidence of femoral condylar avulsion fracture in primary TKA was found to be 1.1%. Over a follow-up period of 1.5-3 years, no instability was noted in any patients. Significant differences were observed between fracture and nonfracture groups in PTVA (82.02 ± 3.39 vs. 85.32 ± 1.87, p = 0.01), DFVA (85.53 ± 2.73 vs. 87.51 ± 5.29, p = 0.02), and HKA (8.81 ± 3.30 vs. 6.53 ± 2.21, p = 0.01). However, the Knee Society Score (KSS) at last follow-up showed no statistical difference (p = 0.05). CONCLUSION: Femoral condylar avulsion fractures during primary TKA may be linked to joint deformities. Fixation methods using cancellous bone screws or nonabsorbable sutures, combined with a hinged knee brace, resulted in favorable clinical and radiological outcomes, with no need for prosthesis modification.