Achieving Correct Balance in Total Knee Arthroplasty with Fixed Varus Deformity

Area of Science:

• Orthopedic Surgery
• Biomechanics

Background:

• Varus knee deformity is a frequent condition requiring total knee arthroplasty (TKA).
• It leads to medial compartment overload, increased forces, and lateral soft tissue lengthening during gait.
• Fixed varus deformities involve medial soft tissue contractures (MCL, posteromedial capsule) and potential bone defects.

Purpose of the Study:

• To discuss the challenges and management strategies for total knee arthroplasty in patients with varus knee deformity.
• To highlight the importance of addressing bone defects and soft tissue contractures.
• To present methods for avoiding complications such as iatrogenic MCL instability and tibial aseptic loosening.

Main Methods:

• Review of surgical considerations for TKA in varus knees.
• Discussion of soft tissue release techniques for gap balancing.
• Evaluation of bone defect management and implant selection (including constrained prostheses).

Main Results:

• TKA demonstrates high long-term implant survivorship, even in severe varus knees.
• Primary knee implants are often suitable, but constrained prostheses may be necessary.
• Specific complications like iatrogenic MCL instability and tibial aseptic loosening can occur.

Conclusions:

• Total knee arthroplasty is a successful treatment for varus knee deformity.
• Addressing medial soft tissue contractures and bone defects is crucial for successful outcomes.
• Careful surgical technique is essential to minimize complications and ensure knee stability.