Revision total knee arthroplasty (TKA) can be technically challenging with potential complications including compromised wound healing, extensor mechanism disruption, intraoperative fracture, bone loss, arthrofibrosis, instability, and increased risk of infection.¹,²,³,⁴ Adequate exposure and proper soft tissue management can help reduce complications, though this can be challenging in revision surgery. While the standard medial parapatellar approach may be adequate, there are several specific surgical techniques that aid the wide exposure necessary for a successful operation. With all techniques, an algorithmic approach will facilitate optimal results.

Selection of the proper skin incision is crucial to optimize healing. In most cases, the previous skin incision can be utilized. In cases where multiple incisions are present, skin necrosis is a possible devastating complication. Skin bridges should be maximized when possible. The blood supply to the skin of the anterior knee arises medially from branches of the saphenous artery (Fig. 64-1). As a general rule, the most lateral incision should be utilized.⁵ This is an “intervascular plane” and thus more likely to heal.⁶ (Fig. 64-2). Extension of the incision proximally and distally into normal tissue is often necessary. The subcutaneous tissue and skin flaps should be kept as thick as possible to decrease the risk of wound healing problems.²

In complex cases, the “sham incision” approach can be used. This method calls for making a skin incision, elevating subcutaneous flaps, and then closing. It is thought that the healing of the skin incision creates a “delay phenomenon,” whereby subsequent tissue survival is increased through the recruitment of new vessels.⁷ Tissue expansion is an additional option in cases of compromised skin.⁸ In general, the surgeon should have a low threshold to consult a plastic surgeon preoperatively.

The medial parapatellar approach provides adequate exposure in most revision TKA cases. A methodical, stepwise approach is necessary to minimize damage to the extensor mechanism. After the arthrotomy has been made, the scar tissue should be excised from the suprapatellar pouch as well as from the medial and lateral gutters. The scar tissue should then be debrided from the peripatellar and infrapatellar regions, completing a tenolysis of the extensor mechanism.⁹ Surgeons should have a low threshold to avoid patellar eversion in an effort to minimize potential catastrophic damage to the extensor mechanism.¹⁰ Alternatively, a smooth pin can be placed in the center of the patellar ligament into the tibial tubercle, acting as a stress reliever to help prevent complete avulsion of the patellar tendon.¹¹ If additional exposure is needed, various techniques can be utilized.

A medial tibial peel can be performed for added exposure by releasing the deep medial collateral ligament and semimembranosus tendon. This should allow for the tibia to be delivered anteriorly with increasing external rotation. As the tibial tubercle continues to rotate laterally, the entire extensor mechanism moves laterally, facilitating access to the lateral tibial plateau ( Video 64-1).

An additional arthrotomy can be made laterally to allow exposure to the anterior aspect of the lateral tibial plateau. Care should be taken to limit the proximal extent of the lateral arthrotomy to the level of the inferior portion of the patella, as this will avoid disruption of the superior lateral genicular artery, the only remaining blood supply to the patella in most cases.

The quadriceps snip evolved from the quadriceps turndown approach, which Insall modified by using a less acute angle with the goal of preserving the superior lateral genicular artery⁵ (Fig. 64-3). The quadriceps tendon is incised at a 45° angle at its most proximal aspect, transecting the rectus femoris tendon near its musculotendinous junction. Combining the medial tibial peel and the quadriceps snip allows lateral mobilization of the extensor mechanism both proximally and distally. This combination is very powerful and can be used to gain adequate exposure in the vast majority of TKA revisions. Even with the combined techniques, no modification of postoperative rehab is needed. If patella eversion remains difficult, you can add a lateral retinacular release or convert the quadriceps incision to a turndown, though this is rarely needed. The quadriceps snip provides excellent exposure
without having to modify postoperative rehabilitation protocols. We perform a quadriceps snip in nearly all revision cases.

The V-Y quadriceps turndown was initially described by Coonse and Adams in 1943 with a distally based inverted V with the apex centered at the proximal limit of the quadriceps tendon¹² (Fig. 64-4). One benefit of the V-Y quadriceps turndown is that it allows for lengthening of the quadriceps tendon, reducing tension on the extensor mechanism and increasing postoperative flexion. This is particularly important for stiff or ankylosed knees. The additional flexion may come at a high cost though, as clinical experience has shown subsequent increases in muscle weakness and extensor lag with this technique.¹,¹³,¹⁴,¹⁵,¹⁶,¹⁷,¹⁸ Additionally, the vascular supply to the patella is severely compromised, increasing the risk of avascular necrosis. Scott and Siliki describe taking the lateral limb of the inverted V distally and laterally, creating exposure through the lateral parapatellar scar and taking care to preserve the lateral superior genicular artery.¹³ The tendon can be repaired with heavy, nonabsorbable sutures, with attention to recreating the appropriate amount of tension. A good guide is an anatomic approximation that allows

flexion to 90°. It is imperative to avoid overlengthening of the tendon, as this can lead to extensor lag. Because of these potential complications, especially the extensor lag, the V-Y turndown is mostly historic and is rarely utilized by the current generation of arthroplasty surgeons. Initial rehabilitation protocols called for 2 weeks of postoperative immobilization. Modern practice is for 0° to 30° with active flexion but only passive extension and toe-touch weight-bearing in a knee immobilizer for the first week. After that, patients are encouraged to advance flexion by 10° daily until the maximum passive flexion achieved intraoperatively is reached. Active extension is commenced at 6 to 8 weeks postoperatively.¹⁹ In our experience, this technique is rarely, if ever, utilized.