Total knee arthroplasty for severe valgus deformity.

Area of Science:

• Orthopedic Surgery
• Biomechanical Engineering

Background:

• Severe valgus knee deformities pose challenges in total knee arthroplasty (TKA).
• Traditional methods risk late instability or require constrained implants.
• A novel soft-tissue release technique was developed in 1985 to address these issues.

Purpose of the Study:

• To describe a specific inside-out soft-tissue release technique for severe valgus knee deformities.
• To evaluate the long-term clinical and radiographic outcomes of this technique in primary TKA.

Main Methods:

• A consecutive series of 71 knees (85 deformities) with 10 degrees valgus underwent TKA using the inside-out release technique.
• The technique involved posterolateral capsular release, iliotibial band pie-crusting, and bone resection.
• Thirty-five patients (42 knees) were followed for a minimum of five years, with clinical and radiographic assessments at 1, 5, and 10 years.

Main Results:

• Significant improvement in Knee Society clinical scores (30 to 93) and functional scores (34 to 81).
• Mean coronal alignment improved from 15 degrees valgus to 5 degrees valgus.
• No cases of delayed instability were reported; three revisions for infection, wear, and loosening occurred.

Conclusions:

• The inside-out soft-tissue release technique is a reproducible method for correcting fixed valgus deformities in TKA.
• This technique yields excellent long-term results, including improved function and coronal alignment, without late instability.