MIS total knee arthroplasty with the limited quadriceps splitting approach

Abstract

In 1974, the first total knee arthroplasty (TKA) was introduced [6, 7]. An extensile approach was utilized with a 20-25 cm midline skin incision. Most commonly, a long medial parapatellar arthrotomy was made [8], although some surgeons preferred a subvastus [5] or midvastus [4] approach. This was followed by extensive soft tissue dissection, as well as eversion and lateral dislocation of the patella. This exposure helped to facilitate appropriate placement of both cutting instruments as well as the components themselves. Over the past 30 years, the techniques of attaining symmetric flexion and extension gaps, ligament balancing, and recreating anatomic alignment have been improved upon so that excellent long term results have been obtained in follow up studies approaching 20 years in length [3, 9, 10, 12, 14, 16]. In the late 1990's, minimally invasive surgery (MIS) for knee arthroplasty was introduced. The theoretical advantages of less invasive surgery included: diminished post-operative morbidity, a reduction in post-operative pain, a decrease in blood loss, and a quicker recovery. While several approaches were initially described, none replaced the standard extensile technique. However, Repicci's work with unicondylar knee replacement encouraged further interest in a limited surgical approach [11, 13]. His successful techniques provided the foundation for MIS total knee replacement. Several limited approaches have evolved from the traditional extensile approach including: the limited quadriceps splitting approach, also known as the limited medial parapatellar arthrotomy, the limited midvastus approach, the limited subvastus approach, and the quadriceps sparing approach. While limiting surgical dissection is the goal of MIS TKA, the integrity of the procedure must not be compromised. Therefore, it is important to note that each of these approaches can be easily converted to the traditional extensile approach if greater exposure is necessary. Not all patients are candidates for minimally invasive surgery. In general, knees with large deformities often require more soft tissue dissection and may even need releases to correct a deformity. Therefore, deformity should be limited to less than 15 degrees of varus and less than 20 degrees of valgus [15]. Larger deformities require greater exposure and cannot be safely performed with a minimally invasive technique. Additionally, the patient should have a minimum pre-operative range of motion of 90 degrees [15]. If a flexion contracture is present, it must be less than 10 degrees [15]. Larger contractures again require more extensive releases and thus cannot be easily accomplished with a minimally invasive approach. Furthermore, patients with complicating medical problems such as rheumatoid or inflammatory arthritis, diabetes, and those patients whom have had prior surgery should be considered for the more traditional extensile exposure [15]. Those patients whom have had previous surgery often have extensive scar tissue which may need to be released to provide adequate exposure of the knee, thus prohibiting a minimally invasive approach. Clinically, we have also noted that muscular males, obese patients, large femurs, or a short patella tendon typically require greater exposure with the traditional techniques [1]. © 2007 Springer Medizin Verlag Heidelberg.