Combined Biplanar Medial Closing-Wedge Distal Femoral Osteotomy and Quadriceps Tendon Medial Patellofemoral Ligament Reconstruction.

Technical Note Combined Biplanar Medial Closing-Wedge Distal Femoral Osteotomy and Quadriceps Tendon Medial Patellofemoral Ligament Reconstruction Lachlan Batty, M.B.B.S., B.Med.Sc., F.R.A.C.S., F.A.O.A., and Alan Getgood, M.Phil., M.D., F.R.C.S.(Tr.&Orth.) Abstract: Lateral patellofemoral instability is multifactorial in etiology, with bony and soft-tissue factors contributing. Coronal plane alignment, in particular genu valgum, is important to consider when evaluating lateral patellofemoral instability. When genu valgum is present and thought to be a significant contributing factor, we typically address this with an extra-articular, biplanar, medial closing-wedge distal femoral osteotomy (DFO). This can be combined with a medial patellofemoral ligament reconstruction using a partial-thickness quadriceps tendon graft via the same incision. A medial closing-wedge DFO with locking plate fixation affords a highly stable construct suitable for early weight-bearing. The locking plate is less prominent as compared with a lateral opening-wedge DFO, and it does not irritate the iliotibial band or cause tightening of the illiopatellar expansion. The biplanar nature of the osteotomy prevents extension of the osteotomy into the proximal trochlear, helps to control rotation in both axial and sagittal plane after wedge removal, and increases the bony surface area for healing. The quadriceps tendon medial patellofemoral ligament reconstruction allows a graft that can be tailored in terms of length and diameter, does not require an anchor on the patellar, and can be performed through the same incision as for the DFO. L ateral patellofemoral instability (LPI) is multifactorial in etiology, with bony and soft-tissue factors contributing. Medial patellofemoral ligament (MPFL) reconstruction has become a mainstay of treatment for many cases of LPI; however, this does not address contributing bony morphologic factors. Patella alta and trochlear dysplasia are examples of contributing bony factors and need careful assessment and management. From St. Vincent’s Hospital, Epworth HealthCare, Western Health Melbourne, Victoria, Australia (L.B.); and Fowler Kennedy Sport Medicine Clinic, 3M Centre, University of Western Ontario, London, Ontario, Canada (A.G.). The authors report the following potential conflicts of interest or sources of funding: A.G. reports grants, personal fees, and other from Smith & Nephew; grants from Ossur; personal fees from ConMed; personal fees and other from Graymont; and personal fees from Precision OS and Olympus, outside the submitted work. Full ICMJE author disclosure forms are available for this article online, as supplementary material. Received January 25, 2021; accepted March 9, 2021. Address correspondence to Dr. Alan Getgood, M.Phil., M.D., F.R.C.S.(Tr.&Orth.), Fowler Kennedy Sport Medicine Clinic, 3M Centre, University of Western Ontario, London, Ontario, N6A 3K7 Canada. E-mail: Ó 2021 by the Arthroscopy Association of North America. Published by Elsevier. This is an open access article under the CC BY-NC-ND license (http:// creativecommons.org/licenses/by-nc-nd/4.0/). 2212-6287/21143 https://doi.org/10.1016/j.eats.2021.03.013 Coronal plane alignment, in particular genu valgum, is also a critical bony factor to consider when evaluating LPI, with important implications on the force vectors of the patellofemoral joint. When genu valgum is present (Fig 1) and thought to be a significant contributing factor, we typically address this with an extra-articular, biplanar medial closing-wedge (MCW) distal femoral osteotomy (DFO). A MCWDFO with locking plate fixation affords a highly stable construct suitable for early weight-bearing. The medial locking plate is less prominent as compared with a lateral opening-wedge DFO, the latter often causing irritation of the iliotibial band and/or tightening of the illiopatellar expansion. The biplanar nature of the osteotomy prevents extension of the osteotomy into the proximal trochlear, controls rotation in both the axial and sagittal planes after wedge removal, and increases the bony surface area for healing.1 An MCWDFO can be combined with an MPFL reconstruction through the same incision using various graft options, including hamstring tendon autograft, allograft, or ipsilateral quadricep tendon graft (Video 1). The quadriceps tendon MPFL reconstruction allows a graft that can be tailored in terms of length and diameter, does not require an anchor on the patellar, and can be performed through the same incision making it our preference in this scenario. Arthroscopy Techniques, Vol 10, No 7 (July), 2021: pp e1685-e1694 e1685 e1686 L. BATTY AND A. GETGOOD Fig 1. Long-leg alignment films demonstrating bilateral genu valgum. The weight-bearing axis is passing well lateral to the center of the knee. BIPLANAR MCWDFO AND QUADRICEPS TENDON MPFL e1687 Fig 2. Preoperative templating of a left-sided medial closing wedge distal femoral osteotomy. (A) The red lines extend from the center of the femoral head and center of the talar dome and meet at the desired point for the postoperative weight-bearing axis. The acute angle subtended by the 2 red lines is transposed from the desired hinge point (*) to the medial femoral cortex. Note this is an isosceles triangle and therefore when the wedge is removed, there will be no cortical step off. The distance at the medial femoral cortex is recorded and used intraoperatively to space the guidewires. (B) A lateral radiograph demonstrating the planes of the cuts for the osteotomy. Note the anterior cut plane helps ensure the osteotomy plane does not enter the proximal trochlear. Surgical Technique (With Video Illustration) Pearls and pitfalls for this technique are listed in Table 1. Templating the Osteotomy We template the osteotomy using a technique based on that described by Dugdale et al.2 (Fig 2). Of note, this original description was for a high tibial osteotomy and when adapting it for a DFO, there is a tendency for overcorrection. This is because the correction is calculated at the joint line; however, the osteotomy is performed above the joint line and therefore the angular correction is applied over a longer distance. A small adjustment can be made to accommodate for this by reducing the correction down to the nearest millimeter. High-quality long-leg alignment films are mandatory, and particular attention should be paid to rotational positioning of the limb. Lateral patellar subluxation is often present in this scenario, and a true anteroposterior view of the distal femur may have the patella laterally positioned. A point for the desired weight-bearing axis after the osteotomy is selected (Fig 2A). We typically aim for a neutral postoperative alignment and select a point between the tibial spines. Lines from the center of the femoral head and middle of the talar dome intersect at this point. The acute angle subtended by these lines is the desired angular correction. This is (...truncated)