Medial patellofemoral ligament reconstruction with simultaneous osteochondral fracture fixation is an effective treatment for adolescent patellar dislocation with osteochondral fractures

Abstract

Background: Osteochondral fractures can occur during patellar dislocation and often require treatment. The purpose of this study is to determine the incidence of recurrent instability and second surgery following osteochondral fracture fixation with concomitant medial patellofemoral ligament reconstruction.

Methods: A retrospective review of a cohort of 365 medial patellofemoral ligament reconstructions by a single surgeon from 2008 to 2019 was performed to identify patients who underwent simultaneous osteochondral fracture fixation with bioabsorbable nails. Demographic data, surgical details, clinical follow-up, and subsequent procedures were collected.

Results: Forty medial patellofemoral ligament reconstructions with osteochondral fracture fixation were performed by a single surgeon from 2008 to 2019. The average age at surgery was 14.6 years (range 10.7-19.6 years). The average length of follow-up was 2.6 years (range 0.7-7.0 years). Eleven (28%) patients required a second surgery on the ipsilateral knee. One patient had recurrent instability and required revision medial patellofemoral ligament reconstruction and osteochondral allograft. The other 10 patients underwent a second surgery to address cartilage damage or debridement of nails. Of the four patients who required nail debridement, the average number of nails initially placed was 7 ± 1.7. This was significantly more than the patients who did not require second surgery related to nail debridement (4.1 ± 1.6, p < .05).

Conclusion: 28% of patients required a second procedure, most of which involved debridement of unhealed portions of the osteochondral fracture. At 2.6-year follow-up, only 2% of patients had a failure of their osteochondral fracture fixation requiring a cartilage restoration procedure. Osteochondral fracture fixation in adolescents with patellofemoral instability can be effectively treated with fixation and simultaneous medial patellofemoral ligament reconstruction.

Level of evidence: level IV.

Keywords: Osteochondral fracture; knee; pediatrics; sports.

Figure 1.

Intraoperative images of a 2 × 2.5 cm² medial facet defect (left). The osteochondral fracture was fixated with six bioabsorbable nails (right) prior to MPFL reconstruction.

Figure 2.

Intraoperative images of a 2 × 2 cm² inferomedial patella defect (left). The two pieces of the osteochondral fracture were fixated with six bioabsorbable nails (right) prior to MPFL reconstruction.

Figure 3.

(a) Preoperative sagittal and (b) axial MRI images of an osteochondral fracture of the patella after patellar dislocation. 1-year postoperative (c) sagittal and (d) axial MRI images showing MPFL reconstruction and healed patellar OCF fixed with bioabsorbable nails.

Figure 4.

Preoperative sagittal MRI image of a loose OCF fragment originating from the lateral femoral condyle (left). Six-month postoperative sagittal MRI image showing healed lateral femoral condyle OCF (right).

Figure 5.

Intraoperative arthroscopic image of OCF taken during a second surgery. The image shows a protruding biodegradable nail and frayed cartilage that subsequently underwent debridement.