Quadricep Sparing (sub-vastus) Total Knee Replacement

What is Subvastus Muscle-Sparing Total Knee Replacement?

Subvastus Muscle-Sparing Total Knee Replacement (SV-MS TKR) is a surgical technique in total knee arthroplasty (TKA) that prioritizes preserving the vastus medialis muscle and its neurovascular integrity. Unlike traditional approaches that often involve extensive manipulation or splitting of the quadriceps muscles, the subvastus approach focuses on minimizing soft tissue trauma, which is a key determinant of recovery outcomes.

What are the Anatomical Considerations for Subvastus Muscle-Sparing Total Knee Replacement?

The vastus medialis obliquus (VMO) plays a critical role in knee stability and function, particularly in maintaining patellar alignment and facilitating knee extension. Preserving this structure during TKA ensures that the extensor mechanism remains intact, which is crucial for postoperative rehabilitation.

What are the Indications and Contraindications for Subvastus Muscle-Sparing Total Knee Replacement?

The subvastus approach is suitable for:

• Individuals requiring primary TKA with intact quadriceps function.
• Those with good soft tissue quality and no significant joint deformities.

Contraindications include:

• Severe valgus or varus deformities requiring extensive soft tissue release.
• Previous surgeries or scar tissue that might impede the approach.

What is the Procedure for Subvastus Muscle-Sparing Total Knee Replacement?

Subvastus Muscle-Sparing Total Knee Replacement Surgical Technique includes the following steps:

• Incision: A medial parapatellar incision is made, extending distally without transecting muscle fibers.
• Retraction: The vastus medialis is gently mobilized to expose the joint capsule.
• Bone Preparation: Standard techniques are employed to prepare the femur and tibia for prosthesis placement, ensuring alignment and stability.
• Prosthesis Placement: Implants are secured with precision, followed by thorough irrigation and closure.

What are the Advantages of the Subvastus Approach Sparing Total Knee Replacement?

Some of the advantages of the Subvastus approach include:

• Enhanced Postoperative Recovery: You can experience reduced pain and improved range of motion due to minimal soft tissue disruption.
• Preservation of Quadriceps Strength: By sparing the vastus medialis, the approach helps maintain your knee's extensor mechanism, crucial for activities like walking and climbing stairs.
• Reduced Rehabilitation Time: Early mobilization is typically possible, facilitating a quicker return to daily activities.
• Minimized Risk of Complications: The approach reduces the likelihood of extensor lag, infection, and wound healing issues compared to more invasive methods.

What are the Outcomes of Subvastus Muscle-Sparing Total Knee Replacement?

Studies have demonstrated superior outcomes with the subvastus approach compared to traditional methods and report higher satisfaction rates, reduced postoperative pain, and faster recovery of knee function.