Surgical Approach for Total Knee Arthroplasty Muscle-Sparing Arthrotomy

Successful total knee arthroplasty depends in part on re-establishment of normal lower extremity alignment, proper implant design and orientation, secure implant fixation, and adequate soft tissue balancing and stability.

Skin Incision

The operative technique for the standard total knee arthroplasty (TKA) involves a skin incision between 16cm (6in) to 30cm (12in). In comparison, when Dr. Luke Vaughan started talking about a “shorter incision” in 2000 for primary total knee arthroplasty, he suggested that 10cm (4in) was a good starting point and the incision could be extended if needed. Since that time, some surgeons are reporting that a skin incision for the Minimally Invasive Solutions™ (MIS™) Quad-Sparing™ technique may be as short as 8cm (3in).

Total knee arthroplasty using a less invasive technique is suggested for non-obese patients with preoperative flexion greater than 90°. Patients with varus deformities greater than 17° or valgus deformities greater than 13° are typically not candidates for a smaller incision technique.

Arthrotomy

The goal of less invasive knee surgery is to limit the muscle and tissue dissection without compromising the procedure. Minimally Invasive TKA can be accomplished through a modified version of one of the standard TKA exposures, Subvastus, Midvastus, Medial Parapatellar or through a MIS Quad-Sparing arthrotomy. The arthrotomy chosen will depend on surgeon preference, experience and training.

MIS Subvastus Arthrotomy The subvastus medial arthrotomy has been slightly modified to optimize minimally invasive surgery. It provides excellent exposure for TKA while preserving all four attachments of the quadriceps to the patella. This approach does not require patellar eversion, minimizes disruption of the suprapatellar pouch, and facilitates rapid and reliable closure of the knee joint.
MIS Midvastus Arthrotomy The midvastus arthrotomy is a muscle splitting approach that involves a 1.5 to 2cm snip into the vastus medialis obliquus where it approaches the quadriceps tendon. The patella may be subluxed or, if desired it may be everted if there is no tension on the patellar tendon. The incision can be extended easily if more visualization is needed. This approach facilitates rapid and reliable closure of the knee joint.
MIS Medial-Parapatellar Arthrotomy The medial parapatellar total knee arthrotomy is the most common approach to standard total knee arthroplasty. The MIS medial parapatellar arthrotomy is a modification of the traditional approach and provides excellent exposure of all three knee compartments. The arthrotomy extends approximately 2cm into the quadriceps tendon. The arthrotomy can be extended easily if more visualization is needed.
MIS Quad-Sparing Arthrotomy The MIS Quad-Sparing approach to the knee joint is an innovative approach initially pioneered by Dr. Thomas M. Coon, Dr. E. Marlowe Goble, and Dr. Alfred J. Tria, Jr. There is no incision into muscle or tendon. The muscle is not moved or disrupted. The suprapatellar pouch is protected. Zimmer Institute training is available for surgeons interested in learning the MIS Quad-Sparing approach to TKA.