Outcomes after knee arthroplasty in extra-articular deformity

Area of Science:

• Orthopedic Surgery
• Biomechanical Engineering

Background:

• Knee osteoarthritis (OA) often presents with extra-articular deformities, complicating treatment.
• Traditional approaches may not fully address complex lower limb alignment issues in OA patients.

Purpose of the Study:

• To evaluate functional outcomes of total knee arthroplasty (TKA) in patients with knee OA and extra-articular deformities.
• To assess the effectiveness of TKA in correcting mechanical axis alignment without prior corrective osteotomy.

Main Methods:

• Prospective evaluation of 33 knees undergoing TKA for OA with extra-articular deformities (25 analyzed).
• Documentation of physical and radiological characteristics pre- and post-operatively.
• Focus on asymmetric intra-articular resection and ligament balancing techniques.

Main Results:

• Significant improvement in Knee Society Score (KSS) from 27.1 to 68.7 (p=0.000).
• Pre-operative mechanical axis deviation corrected, with 20 knees achieving alignment within 3° post-TKA.
• Deformities were primarily due to fractures (16) or failed osteotomies (9).

Conclusions:

• TKA is a viable option for knee OA with extra-articular deformities.
• Asymmetric resection and ligament balancing facilitate pain relief and mechanical axis correction.
• This technique improves functional outcomes in complex knee OA cases.