Modified Recession Wedge Trochleoplasty.

BACKGROUND

Trochlear dysplasia represents one of the main anatomic risk factors for patellar instability, with risk of failure and unfavorable clinical outcomes in patients with unaddressed dysplasia undergoing patellar stabilization.

INDICATIONS

Patients with trochlear dysplasia characterized by supratrochlear prominence (DeJour B or D) and recurrent patellar instability, especially following failed soft tissue or bony stabilization. This technique addresses an anterior trochlea without pathologic convexity, as convexity may require conversion to other techniques for groove deepening (eg, DeJour "thick flap" or Schottle "thin flap").

TECHNIQUE DESCRIPTION

A 6-cm lateral parapatellar arthrotomy is created. A marking pen is used to identify the native center of the trochlea, as well as the location of the planned resection and bony hinge point laterally. An osteotome is used to remove a wedge of bone proximally, such that the posterior aspect of the osteotomy is in line with the anterior femoral cortex. A resection guide is then used to perforate the lateral cortex, with care to avoid damaging the cartilage, and carried laterally and distally to ensure the bony cuts are connected, creating the bony flap. To ensure that all bony bridges are eliminated, the arthroscope is placed into the osteotomy to visualize reduction of the trochlea with manual pressure. A knotless PEEK anchor loaded with 8 loaded sutures is then placed on the roof of the trochlear notch. Sutures are then secured using anchors placed at the center of the trochlea, at the superolateral corner and far lateral edge of the trochlea to reduce the osteotomy, with 2 to 3 sutures placed in each anchor depending on surgeon preference.

RESULTS

Trochleoplasty has been reported to decrease the rate of recurrent patellar dislocation while improving mean Kujala score and knee function. Benefits of trochleoplasty must be balanced against the high rate of potential complications, primarily pain and decreased knee range of motion, secondary to the technical challenges and steep learning curve inherent to effectively performing the procedure.

DISCUSSION/CONCLUSION: Patients with recurrent patellar instability with trochlear dysplasia and failed prior stabilization may experience improved stability and outcomes following trochleoplasty.