Hemitalus Allograft Transplantation for Osteochondral Lesions of the Talus

Abstract

Background:

Osteochondral lesions of the talus (OLTs) are a common pathology seen in the foot and ankle in athletes and are often associated with sports-related injuries. When conservative treatments fail, operative treatment can provide pain relief. For larger lesions, hemitalus allograft transplantation has demonstrated good results.

Indications:

The purpose of this video is to educate surgeons on the indications and surgical technique of the hemitalus allograft transplantation for OLTs. This video describes a clinical case for which this technique was used.

Technique Description:

This video provides an overview of the hemitalus allograft transplantation technique for recurrent, large OLTs.

Results:

Hemitalus allograft transplantation can be an effective surgical option in patients with large OLTs with good prospective results and improvements in patient outcome scores.

Discussion/Conclusion:

Hemitalus allograft transplantation is a safe and effective treatment in patients with large osteochondral lesions of the talus.

Patient Consent Disclosure Statement:

The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Graphical Abstract

This is a visual representation of the abstract.

Video Transcript

In this video, we will discuss the use of a hemitalus allograft transplantation for an osteochondral lesion of the talus in an athlete. This video is prepared by the listed authors from the Medical University of South Carolina in Charleston, South Carolina.

Background

The purpose of this video is to provide a framework for the diagnosis of osteochondral lesions of the talus (OLTs) and describe the use of a hemitalus allograft transplantation technique for the treatment of large osteochondritis dissecans (OCD) lesions. We will begin with a brief overview of the patient's presentation, evaluation, and review of surgical indications. We will then review preoperative imaging and planning. This will be followed by a video describing the surgical technique. Then, we will discuss potential complications, postoperative rehabilitation protocols, return to activity guidelines, and patient outcomes.

OLTs have been found in approximately 6.5% of ankle sprains.^2,8 While common locations of OLTs include posteromedially or anterolaterally, most lesions are located on the medial talar rim in the middle third of the anterior-posterior direction.^1,2 The initial treatment of OCD lesions of the talus is conservative management—including rest, activity modification, ankle bracing, as needed anti-inflammatories, and sometimes injections.^2,6 When conservative treatment options fail to provide adequate relief, surgical options can be considered. The specific surgical procedure is guided by the size of the OCD lesion, with smaller lesions traditionally being treated with bone marrow stimulation techniques such as microfracture, while larger lesions are more likely to fail marrow stimulation techniques, and often various forms of structural graft or autologous chondrocyte implantation can be considered.^3,8 Hemitalus allograft transplantation can be an effective technique in providing a structural allograft for larger OCD lesions, with good prospective results.^7,10

Indications

The patient is a 19-year-old man who has had left ankle pain for 5 years. He is a former high school soccer player and first noticed the pain while playing soccer. In addition to experiencing pain with activity, he reports limited ankle motion and an inability to return to competitive sports due to pain. His previous conservative treatment included anti-inflammatories, bracing, steroid injections, and casting. He also underwent open microfracture of his OCD lesion with iliac crest bone grafting 4 years before presentation. This did not provide lasting relief. On physical examination, his motion was limited to 5° of dorsiflexion to 20° of plantarflexion with preserved subtalar motion and stable ankle Lachman with tenderness to palpation over the anterior ankle joint line.

Preoperative radiographs demonstrated a large osteochondral lesion of the anterior lateral dome of the talus with intra-articular fragments and early osteophyte formation on the anterior aspect of the ankle joint.

Preoperative computed tomography redemonstrated a large 2 × 3–cm osteochondral defect of the anterior lateral aspect of the talus with anterior ankle osteophytes but otherwise well-preserved tibiotalar cartilage.

Preoperative magnetic resonance imaging (MRI) of the left ankle redemonstrated a 1.5 ×1.2 × 2.8–cm OCD lesion within the anterolateral aspect of the talus with tibiotalar arthritis.

In summary, this was a 19-year-old man with a large, unstable left OCD of the anterolateral talus with tibiotalar arthritis. Given his continued symptoms refractory to previous conservative management, the risks/benefits of surgery were discussed, and they elected to proceed. We discussed a variety of surgical options, including joint salvage procedures with open debridement with hemi-talar allograft versus ankle arthrodesis. Given the patient's age, size of the lesion, and the patient's goal to maintain his ankle range of motion and relieve pain, he elected to proceed with hemitalar allograft transplantation.

Technique Description

The patient was positioned supine with a thigh tourniquet, bump under the ipsilateral hip, and a C-arm from the contralateral side.

A standard anterior approach to the ankle was performed. A longitudinal skin incision was made over the anterior ankle. Care was taken to identify the superficial peroneal nerve, which was mobilized laterally. The interval between the tibialis anterior and the extensor hallucis longus was identified, and the extensor retinaculum was opened in line with the skin incision. The neurovascular bundle was identified laterally, mobilized laterally, and protected throughout the case. An arthrotomy was created over the anterior ankle. There were extensive osteophytes—especially over the anterior talar neck. A rongeur and an osteotome were used to remove the osteophytes from the distal tibia and talar neck. There was a large, unstable OCD visualized. This was measured to be at least 2 × 1.5 cm over the lateral talar shoulder. The OCD defect was debrided. A marker was used to delineate the resection lines. A K-wire was placed in line with the planned resection. This was verified under fluoro. An oscillating saw was used to resect the lateral portion of the talus, also known as the talar body. The K-wire was removed. The OCD lesion was resected. Next attention was turned to the back table. This picture diagrams our measurements of the defect. The fresh talus allograft was measured. A K-wire was used to create a border for planned resection. The allograft was cut with an oscillating saw. This graft was placed to fill the defect of the lateral talus shoulder, which nicely restored the lateral portion of the talar body and cartilage. A K-wire was then placed temporarily to fixate the allograft. Biplanar fluoroscopy, as well as direct visualization, confirmed the appropriate position. Multiple holes were then drilled for a minifragment screw. A 2.0-mm screw from the mini fragment set was selected and applied from the allograft into the talar body. This screw was countersunk below the level of the cartilage. This was repeated for a second screw. The graft was checked to maintain smooth edges with the rest of the talus. The ankle was taken through range of motion to evaluate for any signs of impingement. The graft was noted to be stable.

Results

Biplanar fluoroscopy confirmed the appropriate position of the graft as well as all the hardware. Final fluoroscopic images are shown demonstrating the appropriate position of the graft with screw fixation.

These are postoperative radiographs at 6 weeks demonstrating the graft and hardware with no evidence of complications.

These are postoperative radiographs at 12 weeks, demonstrating interval incorporation of the graft. At this visit, the patient was found to have significant improvements in his range of motion from 10° of dorsiflexion to 35° of plantarflexion.

These are postoperative radiographs at 6 months demonstrating a well-aligned tibiotalar joint with a stable talar hemi allograft, with intact hardware. At this visit, his range of motion was 10° of dorsiflexion to 40 degrees of plantar flexion.

Here are the patient-reported outcome measures and pain scores at 6 months.

Potential complications of this procedure include allograft-associated infection, subchondral collapse, delayed union or nonunion, graft fragmentation, or allograft subsidence.

The postoperative rehabilitation protocol includes weeks 1 to 2 of nonweightbearing in a short leg splint. Then, transitioning from a splint to a short leg cast and remaining nonweightbearing for 4 more weeks. At week 7, the patient is transitioned to nonweightbearing in a CAM boot and begins working on ankle range of motion with physical therapy. At week 12, the patient can weight bear in a CAM boot and wean as tolerated, continuing with physical therapy on ankle range of motion exercises. At 6 months, the patient begins low-impact cardio activities. At 9 months, he can start light jogging.

Discussion/Conclusion

The literature review of this surgical option has demonstrated good outcomes over time, but there remains a lack of data detailing long-term follow-up. A study by El-Rashidy et al ⁴ looked at 42 patients who underwent fresh talar allograft transplantation with a mean age of 44 years and a mean follow-up of 38 months. There was a significant improvement in American Orthopaedic Foot & Ankle Society (AOFAS) scores and in patient satisfaction. MRIs obtained in 15 patients postoperatively showed minimal graft subsidence, maintained graft stability, and maintained articular surface. There were 4 graft failures and a 12% reoperation rate. A systematic review by VanTienderen et al ⁹ looked at 5 studies, a total of 91 cases of OLTs treated with fresh talar allografts, with a mean age of 39 years and a mean follow-up of 45 months. AOFAS scores increased, and visual analog scale pain (VAS-Pain) scores decreased, with 25% of patients requiring at least 1 reoperation. A recent prospective study by Fletcher et al ⁵ looked at 31 patients undergoing talar allograft transplantation. At a mean follow-up of 56 months, the graft survival rate was 97%. There was a significant improvement in VAS and Short Musculoskeletal Function Assessment scores. In their study, 48% of patients underwent additional surgery, primarily for debridement or hardware removal, with 1 patient undergoing total ankle arthroplasty. ⁵

Overall, this presentation and technique video demonstrates that hemitalus allograft transplantation can be a safe and effective treatment for large OLTs.