Autogenous structural bone graft reconstruction of uncontained significant medial proximal tibial bone defects in primary total knee arthroplasty

Abstract

Purpose: Tibial bone defects in total knee arthroplasty (TKA) pose a significant challenge for surgeons, potentially causing improper component balancing. We studied the outcomes of autogenous structural bone grafting
with screws to address medial proximal tibial defects in primary TKA with varus deformity.
Methods: A prospective study was conducted at Elite Hospital’s Orthopedic Department in Sana’a City between
2020 and 2024. Patients with uncontained medial proximal tibial defects 10–25 mm in depth who underwent
primary TKA for varus deformity were managed using autogenous structural bone grafts fixed with screws and
followed up for at least 40 months. Patients were followed up clinically using the Knee Society Score (KSS).
Radiological follow-up was performed to assess bone graft union and implant stability.
Results: The study included 29 patients with a mean age of 59.3 ± 7.2 years. Twenty (69%) were female, and
nine (31%) were male. The median BMI was 28.3 (IQR, 26.30–29.30) kg/m2. The mean defect depth was 13.2
± 3.0 mm, with a mean follow-up duration of 55.3 ± 1.3 months. The median (IQR) preoperative KSS increased
from 27 (23–34) to 91 (90–93) points at the last follow-up (P < 0.05), and the median (IQR) knee ROM improved
from 84.0° (67° –109°) to 128.9° (122.1° –140.9°) (P < 0.05). Flexion contractures and varus deformities were
completely resolved postoperatively (P <0.05). The mean graft union time was 8.2 ± 1 months. The overall
complication rate was 13.7%.
Conclusion: The use of autogenous bone grafting fixed with screws to manage large uncontained medial proximal tibial defects in primary TKA with varus deformity is a viable and successful treatment option.