Mini-subvastus versus a standard approach in total knee arthroplasty: a prospective, randomized, controlled study

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering

Background:

• Total knee arthroplasty (TKA) is a common procedure for knee osteoarthritis.
• Minimally invasive surgical approaches aim to reduce patient morbidity.
• The mini-subvastus approach is one such technique for TKA.

Purpose of the Study:

• To compare clinical and radiological outcomes of primary TKA using a mini-subvastus versus a standard surgical approach.
• To evaluate early and long-term functional recovery and patient-reported pain.

Main Methods:

• Prospective randomized study comparing mini-subvastus (n=35) and standard (n=33) approaches for primary TKA.
• Posterior-stabilized prosthesis used in all cases by the same surgeon.
• Follow-up of 18 months (range 14-26 months) assessing blood loss, pain, range of motion, and radiological outcomes.

Main Results:

• The mini-subvastus group experienced less blood loss and pain at 1 day post-operatively.
• Earlier active straight leg raise and fewer lateral retinacular releases were observed in the mini-subvastus group.
• While functional outcomes were better up to 9 months in the mini-subvastus group, no significant differences were found at 1 year or final follow-up. Reduced access led to longer operation times and technical errors in this group.

Conclusions:

• The mini-subvastus approach offers short-term advantages in TKA recovery.
• Long-term functional and radiological outcomes are comparable to the standard approach.
• Technical challenges associated with the mini-subvastus approach necessitate its use in selected cases only.