Residency Insight -- A PRESENT Podiatry eZine

Volume 4 - Issue 21

Ryan Fitzgerald, DPM
PRESENT RI Associate Editor
Hess Orthopedics &
Sports Medicine
Harrisonburg, Virginia

Case Conclusion: Persistent Lateral Ankle Pain in a 33-year-old male

We received a few great responses to part 1 of this case presentation in the eTalk thread on this topic, and as many of you noted, the patient demonstrated a large posterior lateral talar dome lesion with subchondral bone involvement.

Figure 1. Pre-op MRI imagery

Surgical Strategy: Considering the size and location of this lesion, as well as his previous history of attempts at arthroscopic management with microfracture, the decision was made to attempt to address this lesion via open arthrotomy via lateral malleolar osteotomy. Considering the depth of the lesion, and the underlying osseous involvement, there were a number of surgical options to address the lesion available, including; autogenous OATS, fresh allograft OATS, and packing with bone grafting into the lesion with application of DeNovo NT living cartilage graft.

Considering the adverse side effects and potential for the development of knee pain, the decision was made not to perform an autogenous OATS harvest, and due to scheduling and hospital issues, fresh allograft talus was unavailable, so the decision was made to utilize the DeNovo NT graft in conjunction with bone grafting to fill the underlying talar cyst. The DeNovo NT Graft consists of scaffold-free living articular cartilage, harvested from pediatric donors, that displays the biochemical properties that are similar to those of articular cartilage found in young, healthy adults

Surgical Procedure: A lateral approach was performed with an oblique lateral malleolar osteotomy and the talar defect was identified. It was debrided utilizing curettage and all nonviable cartilaginous and osseous debris was removed (fig 2). Bone graft harvested from the calcaneous was then packed into the underlying cystic lesion. The DeNovo NT graft was then gently layered into the defect and was secured in place utilizing fibrin glue (fig. 3). The lateral malleolar osteotomy was then repaired utilizing a laterally placed fibular plate. The patient was then placed into an Ilizarov external fixator to provide arthrodiastasis about the right ankle, and to allow the patient to perform limited weight bearing during the post-operative course of care (fig. 4). The Orthofix TrueLok frame with telescoping rods was utilized to provide approximately 7-8mm of distraction at the ankle. The first 5mm was obtained intra-operatively, and the additional 2-3 mm was obtained post-operatively in 0.25 mm increments.

Figure 2.

Figure 3.

Figure 4.

Post Operative Course: The patient demonstrated an uneventful postoperative course (fig. 5). He was seen weekly for pin-site evaluations and at approximately 12 weeks post-op he was returned to the operating room for removal of the external fixators. An ankle arthroscopy was performed at the time of the frame removal and the area of cartilaginous grafting was observed visually. There was evidence of mild hypertrophic cartilaginous overgrowth, which was trimmed and a portion of this tissue was obtained for biopsy, which demonstrated “cartilaginous hyperplasia.” The lesion site demonstrated no visible areas of delaminating cartilage, and radiographically the cystic lesion appeared to have resolved. The patient is currently six months post-op and has returned to full activity with no further pain and with no physical limitations.

Figure 5.

Discussion: This case provided a variety of challenges. The De Novo NT graft provided an excellent alternative to more classic OATS-type osteochondral harvest procedures as there was no donor site morbidity. The application process was technically easy to perform, and there appeared to be complete clinical resolution of the talar defect. An ankle arthrodiastasis was performed in conjunction with the grafting procedure to provide protection to the DeNovo NT graft during its incorporation and to allow for limited weight bearing during the patient’s post-operative course. The Orthofix Truelok external fixation system was selected for the arthrodiastasis component of this procedure due to the ease of application, strength, and relative low cost.

We at PRESENT love hearing from you. I would encourage you to share your experience, pearls, and wisdom on this topic, or on any other that you would like to share with our online community via eTak. Your continued participation is what makes this Web portal great!