Participation in Sports or Recreational Activities After Osteochondral Allograft Transplantation of the Talus.

BACKGROUND: Fresh osteochondral allograft (OCA) transplantation is a viable treatment option for osteochondral defects of the talus. However, sufficient data are not available on patients' participation in sports or recreational activities after the procedure. PURPOSE: To assess whether patients undergoing OCA transplantation of the talus participated in sports or recreational activities postoperatively. STUDY DESIGN: Case series; level of evidence, 4. METHODS: A total of 36 ankles in 34 patients underwent OCA transplantation of the talus. At a mean follow-up of 9.2 years, information on participation in sports or recreational activities pre- and postoperatively was obtained, as well as postoperative pain, function, and satisfaction. RESULTS: The mean age at the time of surgery was 36.1 years (range, 20.5-57.7 years), and 50% of patients were men. The mean graft size was 3.6 cm2 (range, 1-7.2 cm2) or 41.1% of the talar dome. Before the injury, 63.9% of patients (23/36 ankles) reported being highly competitive athletes or well trained and frequently sporting; 36.1% of patients (13/36 ankles) reported sometimes sporting or were nonsporting. Also, 66.7% of patients (24/36 ankles) were able to participate in sports or recreational activities after OCA transplantation and 50% (18/36 ankles) were still participating in sports or recreational activities at the latest follow-up. In a subset of well-trained or highly competitive athletes, 73.9% (17/23 ankles) were able to return to sports or recreational activities at any point after OCA transplantation, and 65.2% (15/23 ankles) were still participating at the latest follow-up. Further surgery occurred in 16.7% of patients (6/36 ankles). Graft survivorship was 94.3% at 5 years and 85.3% at 10 years. There was a significant improvement in the mean Olerud-Molander Ankle Scores, and the mean Foot and Ankle Ability Measure scores were high postoperatively. Moreover, 79.4% of patients (27/34 ankles) were either satisfied or extremely satisfied with the allograft surgery. CONCLUSION: Fresh OCA transplantation is a reasonable surgical option for osteochondral defects of the talus for young, active patients who have failed previous operative management or have massive defects.

Partial talar replacement with a novel 3D printed prosthesis.

BACKGROUND: The treatment of talus avascular necrosis (AVN) is challenging owing to its unique anatomical features. Despite decades of studies, till date, there is no appropriate treatment for talus AVN. Therefore, surgeons need to develop newer surgical methods. In the present study we introduce a new surgical method, 3D printed partial talus replacement (PTR), to treat partial talus necrosis and collapse (TNC). METHODS: A male patient with talus AVN underwent PTR in our hospital. The morphology of the talus was quantified using 3D computed tomography (CT) imaging. A novel 3D printed titanium prothesis was designed and manufactured according to the findings of the CT imaging. The prosthesis was applied during talus replantation surgery to reconstruct the anatomical structure of the ankle. The follow-up period for this patient was 24 months. The visual analog scale (VAS) scores before and after surgery, American Orthopedic Foot and Ankle Score (AOFAS), ankle range of motion, and postoperative complications were recorded to evaluate the prognosis. RESULTS: The anatomical structure of the talus was reconstructed. The patient was satisfied with the effects of treatment, recovery, and function. The VAS score decreased from 5 to 1. The AOFAS improved from 70 to 93. The range of motion remained the same as that during the pre-operation. The patient returned to a normal life. CONCLUSION: 3D printed PTR is a new surgical method for talus AVN that can provide satisfactory outcomes. In future, PTR might be an effective and preferential treatment for the treatment of partial talus AVN and collapse.

Outcomes of Talar Osteochondral and Transchondral Lesions Using an Algorithmic Approach Based on Size, Location, and Subchondral Plate Integrity: A 10-Year Study on 204 Lesions.

The management of transchondral and osteochondral talar lesions has evolved, with microfracturing originally considered the best initial treatment. Despite talar lesions being a tri-dimensional defect, most studies use 2-dimensional parameters to grade them. We propose in this study that tri-dimensional sizing may be more appropriate in evaluation for treatment. The present study evaluated the outcomes of treatment of talar lesions performed by a single surgeon, creating and using an algorithm based on volume, location, and integrity of the subchondral plate. The lesions were classified as "small" (up to 125 mm3), "medium" (125 mm3-1500 mm3), and "large" (>1500 mm3) based upon evaluation of the preoperative magnetic resonance imagining. Location of the lesion was also noted on a 9-region grid pattern of the talar dome. These 3 parameters dictated whether a lesion required microfracturing or retrograde drilling, autogenous or allogenous bone graft, and whether an open versus an arthroscopic approach was required. Over a 10-year period, surgery was performed on 204 lesions. Overall, the average time to return to activity was 7.93 ± 5.00 (range 2-36) months. The average preoperative American Orthopaedic Foot and Ankle score was 76.44 ± 10.98 (range 52-86), and the average postoperative American Orthopaedic Foot and Ankle score was 96.12 ± 3.46 (range 81-100), p = .0001. By using the proposed algorithm, the outcome and return to activity for most patients can be better predicted, regardless of the size or location of the osteochondral lesion. The treatment algorithm implemented in the present investigation yielded overall acceptable results, with only 7 of the 204 lesions needing additional surgery.

Autologous Osteochondral Transplantation for Large Osteochondral Lesions of the Talus Is a Viable Option in an Athletic Population.

BACKGROUND: Autologous osteochondral transplantation (AOT) has been shown to be a viable treatment option for large osteochondral lesions of the talus. However, there are limited data regarding the management of large lesions in an athletic population, notably with regard to return to sport. Our investigation focused on assessing both qualitative and quantitative outcomes in the high-demand athlete with large (>150 mm2) lesions. HYPOTHESIS: AOT is a viable option in athletes with large osteochondral lesions and can allow them to return to sport at their preinjury level. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: The study population was limited to professional and amateur athletes (Tegner score, >6) with a talar osteochondral lesion size of 150 mm2 or greater. The surgical intervention was AOT with a donor site from the lateral femoral condyle. Clinical outcomes at a minimum of 24 months included return to sport, visual analog scale (VAS) for pain score, and Foot and Ankle Outcome Score (FAOS). In addition, graft incorporation was evaluated by magnetic resonance imaging (MRI) using MOCART (magnetic resonance observation of cartilage repair tissue) scores at 12 months after surgery. RESULTS: A total of 38 athletes, including 11 professional athletes, were assessed. The mean follow-up was 45 months. The mean lesion size was 249 mm2. Thirty-three patients returned to sport at their previous level, 4 returned at a lower level compared with preinjury, and 1 did not return to sport (mean return to play, 8.2 months). The VAS improved from 4.53 preoperatively to 0.63 postoperatively (P = .002). FAOSs improved significantly in all domains (P < .001). Two patients developed knee donor site pain, and both had 3 osteochondral plugs harvested. Univariant analysis demonstrated no association between preoperative patient or lesion characteristics and ability to return to sport. However, there was a strong correlation between MOCART scores and ability to return to sport. The area under receiver operating characteristic of the MOCART score and return to play was 0.891 (P = .005), with a MOCART score of 52.50 representing a sensitivity of 0.85 and specificity of 0.80 in determining ability to return to one's previous level of activity. CONCLUSION: Our study suggests that AOT is a viable option in the management of large osteochondral talar defects in an athletic population, with favorable return to sport level, patient satisfaction, and FAOS/VAS scores. The ability to return to sport is predicated upon good graft incorporation, and further research is required to optimize this technique. Our data also suggest that patients should be aware of the increased risk of developing knee donor site pain when 3 osteochondral plugs are harvested.

Osteochondral Allograft: Proceedings of the International Consensus Meeting on Cartilage Repair of the Ankle.

BACKGROUND: The evidence supporting best practice guidelines in the field of cartilage repair of the ankle is based on both low quality and low levels of evidence. Therefore, an international consensus group of experts was convened to collaboratively advance toward consensus opinions based on the best available evidence on key topics within cartilage repair of the ankle. The purpose of this article is to report the consensus statements on "Osteochondral Allograft" developed at the 2017 International Consensus Meeting on Cartilage Repair of the Ankle. METHODS: Seventy-five international experts in cartilage repair of the ankle representing 25 countries and 1 territory were convened and participated in a process based on the Delphi method of achieving consensus. Questions and statements were drafted within 11 working groups focusing on specific topics within cartilage repair of the ankle, after which a comprehensive literature review was performed and the available evidence for each statement was graded. Discussion and debate occurred in cases where statements were not agreed upon in unanimous fashion within the working groups. A final vote was then held, and the strength of consensus was characterized as follows: consensus, 51% to 74%; strong consensus, 75% to 99%; and unanimous, 100%. RESULTS: A total of 15 statements on osteochondral allograft reached consensus during the 2017 International Consensus Meeting on Cartilage Repair of the Ankle. One achieved unanimous support and 14 reached strong consensus (greater than 75% agreement). All statements reached at least 85% agreement. CONCLUSIONS: This international consensus derived from leaders in the field will assist clinicians with osteochondral allograft as a treatment strategy for osteochondral lesions of the talus.

Review of Mechanical, Processing, and Immunologic Factors Associated With Outcomes of Fresh Osteochondral Allograft Transplantation of the Talus.

Osteochondral lesions of the talus (OLTs) are an increasingly implicated cause of ankle pain and instability. Several treatment methods exist with varying clinical outcomes. Due in part to successful osteochondral allografting (OCA) in other joints, such as the knee and shoulder, OCA has gained popularity as a treatment option, especially in the setting of large lesions. The clinical outcomes of talar OCA have been inconsistent relative to the positive results observed in other joints. Current literature regarding OCA failure focuses mainly on 3 factors: the effect of graft storage conditions on chondrocyte viability, graft/lesion size, and operative technique. Several preclinical studies have demonstrated the ability for bone and cartilage tissue to invoke an immune response, and a limited number of clinical studies have suggested that this response may have the potential to influence outcomes after transplantation. Further research is warranted to investigate the role of immunological mechanisms as an etiology of OCA failure. LEVEL OF EVIDENCE: Level V, expert opinion.

Obtaining Correct Ankle Alignment Using Intraoperative External Fixation for Ankle Arthrodesis.

Ankle arthrodesis remains an important treatment option for patients with ankle arthritis. Many methods have been described; however, no consensus has been reached regarding the best technique to achieve both successful fusion and a good position for optimal foot mechanics. Furthermore, as arthroplasty has become more popular, preservation of the fibula to allow for future arthroplasty has become critical. The present report describes an innovative technique in which temporary external fixation at operative fixation is used, along with internal fixation, to achieve both an optimal foot position and high fusion rates, while maintaining the integrity of the fibula. Seventeen patients were identified who met the criteria for inclusion. Their medical records, including pre- and postoperative radiographs, were reviewed retrospectively. Preoperative and postoperative coronal and sagittal alignment was determined. All patients achieved successful fusion, although 1 (5.9%) patient experienced delayed union. The average tibial/talar ratio preoperatively was 21% (range 8% to 33%), demonstrating anterior subluxation. Postoperatively, this ratio improved to 33% (range 26% to 40%), approximating the normal anatomic ratio. Of the 17 patients, 5 (29.4%) had preoperative varus or valgus alignment of the talas >5°. All 5 cases were successfully corrected to within 2° of normal anatomic alignment. This technique allows the surgeon to achieve good visualization of the joint for preparation and to obtain the optimal position of the foot at arthrodesis without compromising the lateral column significance of the fibula. All patients obtained fusion, and minimal complications were associated with the use of this technique.

Computer Modeling Analysis of the Talar Dome as a Graft for the Humeral Head.

PURPOSE: To study the degree of surface congruency between the talar dome and humeral head, to determine the size of graft harvestable from the talar dome, and to determine if there are surrogate markers that correspond to a higher degree of surface congruency. METHODS: Computer models of 7 nonmatched humeral heads and 7 talar domes were generated by digital segmentation of magnetic resonance (MR) images. Modeled defect regions of each humeral head were then aligned with medial and lateral surfaces of each talar dome using software to maximally limit surface mismatch. Modeled defect sizes ranging from 24 × 10 mm to 30 × 10 mm were tested. Congruence match of <1 mm separation was then measured. RESULTS: The average surface match between randomly selected talar domes to humeral head surfaces was 87.2% when 1 mm was selected as the maximal acceptable congruence difference. Congruence match was not affected by graft size or laterality of talar dome as source of graft. Matching radius of curvature of talar dome to humeral head and height of donor to recipient correlated with improved congruence match. Under best match conditions, a maximal congruence match of 95.2% was achieved. CONCLUSIONS: The present study indicates that the talar dome can be a potential source of osteochondral allograft for Hill-Sachs lesions with a maximal defect size of 30 × 10 mm for a single graft. Larger graft sizes resulted in decreased success of actual graft harvest as a result of dimensional constraints of the talar dome. Additional studies are required to determine the biomechanical compatibility of this graft. CLINICAL RELEVANCE: The talar dome has a high degree of surface congruency in comparison with the humeral head though the maximal graft size harvestable limits its clinical applicability.

Role of Fresh Osteochondral Allografts for Large Talar Osteochondral Lesions.

Osteochondral lesions of the talus, large or small, present a challenge to the treating orthopaedic surgeon. These cartilage and bony defects can cause substantial pain and functional disability. Surgical treatment of small lesions of the talus has been thoroughly explored and includes retrograde drilling, arthroscopic débridement and marrow stimulation, osteochondral autografting from cartilage/bone unit harvested from the ipsilateral knee (mosaicplasty), and autologous chondrocyte implantation. Although each of these reparative, replacement, or regenerative techniques has various degrees of success, they may be insufficient for the treatment of large osteochondral lesions of the talus. Large-volume osteochondral lesions of the talus (>1.5 cm in diameter or area >150 mm) often involve sizable portions of the weight-bearing section of the talar dome, medially or laterally. To properly treat these osteochondral lesions of the talus, a fresh structural osteochondral allograft is a viable treatment option.

Comparison of Osteochondral Autografts and Allografts for Treatment of Recurrent or Large Talar Osteochondral Lesions.

BACKGROUND: The purpose of this study was to prospectively evaluate and compare the long-term clinical and radiographic outcomes of using osteochondral autograft and allograft to manage either recurrent or large osteochondral lesions of the talar dome (OLT) in a single surgeon's practice. METHODS: Between January 2008 and January 2014, a total of 40 patients presented with either a recurrent OLT that failed initial arthroscopic treatment (ie, excision, curettage, debridement, and micro-fracture) or a primary OLT greater than 1.5 cm2 that had undergone no prior surgery. Before surgery, 20 patients were randomized to receive osteochondral autograft plugs (Arthrex, Naples, FL) from the ipsilateral superolateral distal femoral condyle whereas the remaining 20 were randomized to receive osteochondral allograft plugs from a fresh size-matched donor talus (Joint Restoration Foundation, Centennial, CO, and Arthrex, Naples, FL), but 4 of these were excluded that received a hemi-talus allograft with internal fixation. Preoperative and postoperative function and pain was graded using the Foot and Ankle Ability Measures (FAAM) scoring system and a Visual Analog Scale (VAS) of pain, respectively. Radiographs were assessed for osteochondral graft healing, joint congruency, and degenerative changes. Data regarding postoperative complications and revision surgeries were also recorded. RESULTS: Of the 20 patients who received osteochondral autograft, the mean FAAM score increased from 54.4 preoperatively to 85.5 at the time of final follow-up. The mean VAS pain score decreased from 7.9 of 10 preoperatively to 2.2 of 10 at final follow-up. Two patients (10%) that received osteochondral autograft, 1 for a recurrent OLT of 1.3 cm2 and 1 for a primary OLT of 2.0 cm2, developed a symptomatic nonunion at the entire graft site. Both of these patients had their autograft converted to talar allograft plugs and achieved full osteochondral healing. At the time of final follow-up, no patients who received osteochondral autograft developed ankle degenerative changes or knee complications. The mean FAAM score of the 16 patients who received osteochondral allograft plugs increased from 55.2 preoperatively to 80.7 at the time of final follow-up. This postoperative score was lower than that of the osteochondral autograft group, but not to a statistically significant degree (P = .25). The mean VAS pain score decreased from 7.8 of 10 preoperatively to 2.7 of 10 at final follow-up. This postoperative score was higher than that of the osteochondral autograft group but not to a statistically significant degree (P = .15). Three patients (18.8%) that received osteochondral talar allograft, 2 for recurrent OLTs less than 1.5 cm2 and 1 for a primary OLT of 2.2 cm2, developed a symptomatic nonunion at the entire graft site. Two of these 3 patients had their allograft converted to osteochondral autograft plugs harvested from the ipsilateral superolateral distal femoral condyle and achieved full osteochondral healing. At the time of final follow-up, 1 of these 16 (6.3%) patients who received talar allograft as OLT treatment had developed asymptomatic anterior ankle arthritis upon radiographs. CONCLUSION: Using fresh talar osteochondral allograft provided results that were comparable to the use of distal femoral osteochondral autograft for treating recurrent or large OLTs. Although the use of allograft avoided the risk of knee complications when harvesting autograft from the distal femur, fresh talar allograft may have lower healing rates than osteochondral autograft. LEVEL OF EVIDENCE: Level II, comparative case series.

The use of allograft in joint-preserving surgery for ankle osteochondral lesions and osteoarthritis.

The surgical management of young patients with large osteochondral lesions of the talus or end-stage osteoarthritis of the ankle joint presents a challenge to the orthopedic surgeon because these are well-recognized sources of pain and dysfunction. Procedures designed to address these disorders either have a limited role because of poor success rates or have significant implications, such as with the total ankle arthroplasty. Fresh osteochondral allografts allow defective tissue to be anatomically matched and reconstructed through transplantation. This article presents an overview of fresh osteochondral allografts, as well as potential concerns with their use, and summarizes the current literature.

Operative treatment of osteochondral lesions of the talus.

➤ Osteochondral lesions of the talus are common injuries in recreational and professional athletes, with up to 50% of acute ankle sprains and fractures developing some form of chondral injury. Surgical treatment paradigms aim to restore the articular surface with a repair tissue similar to native cartilage and to provide long-term symptomatic relief.➤ Arthroscopic bone-marrow stimulation techniques, such as microfracture and drilling, perforate the subchondral plate with multiple openings to recruit mesenchymal stem cells from the underlying bone marrow to stimulate the differentiation of fibrocartilaginous repair tissue in the defect site. The ability of fibrocartilage to withstand mechanical loading and protect the subchondral bone over time is a concern.➤ Autologous osteochondral transplantation techniques replace the defect with a tubular unit of viable hyaline cartilage and bone from a donor site in the ipsilateral knee. In rare cases, a graft can also be harvested from the ipsilateral talus or contralateral knee. The limitations of donor site morbidity and the potential need for an osteotomy about the ankle should be considered. Some anterior or far posterior talar lesions can be accessed without arthrotomy or with a plafondplasty.➤ Osteochondral allograft transplantation allows an osteochondral lesion with a large surface area to be replaced with a single unit of viable articular cartilage and subchondral bone from a donor that is matched to size, shape, and surface curvature. The best available evidence suggests that this procedure should be limited to large-volume cystic lesions or salvage procedures.➤ Autologous chondrocyte implantation techniques require a two-stage procedure, the first for chondrocyte harvest and the second for implantation in a periosteum-covered or matrix-induced form after in vivo culture expansion. Theoretically, the transplantation of chondrocyte-like cells into the defect will result in hyaline-like repair tissue.

Particulated juvenile articular cartilage allograft transplantation for osteochondral lesions of the talus.

Osteochondral lesions of the talus can present a challenge to the orthopedic surgeon. Because of its avascular nature, articular cartilage has a poor capacity for self-repair and regeneration. A wide variety of strategies have been developed to restore the structure and function of injured cartilage. Surgical strategies range from repair of cartilage through the formation of fibrocartilage to a variety of restorative procedures, including tissue-engineering-based strategies. A novel treatment option involves the implantation of particulated articular cartilage obtained from a juvenile allograft donor, the DeNovo NT graft. This article reviews the DeNovo NT graft, its usage, and surgical technique.

Cell cultured chondrocyte implantation and scaffold techniques for osteochondral talar lesions.

Cell cultured techniques have gained interest and popularity in osteochondral defects because, unlike bone marrow stimulation methods, where fibrocartilage fills the defect, they allow for the regeneration of "hyaline-like cartilage" with better stiffness, resilience, and wear characteristics. Osteochondral defects in the ankle are a rare but challenging problem to treat in young active patients. If left alone, they can cause pain and reduced function and risk progressive degenerative changes in the joint. Clinical results of cell cultured and scaffold technology in the ankle, although still limited by small studies and midterm follow-up, are certainly encouraging.

Bipolar fresh osteochondral allografting of the tibiotalar joint.

BACKGROUND: Tibiotalar arthritis in the young, active patient is a debilitating condition with limited treatment options. Bipolar tibiotalar fresh osteochondral allograft transplantation was conceived as a possible alternative to arthrodesis and arthroplasty. We reported our experience with bipolar ankle osteochondral allografts for the treatment of tibiotalar joint arthritis. METHODS: Between 1999 and 2008, we performed bipolar ankle allografts in eighty-eight ankles (eighty-four patients). Eighty-six ankles (eighty-two patients) had a minimum follow-up duration of two years. The mean patient age was forty-four years and 52% of the patients were male. Evaluation included frequency and type of reoperations, the Olerud-Molander Ankle Score, pain, function, and patient satisfaction. Radiographs were evaluated for graft healing, joint space narrowing, and graft collapse. RESULTS: The mean duration of follow-up was 5.3 years (range, two to eleven years). Thirty-six (42%) of the eighty-six ankles that had undergone allograft had further surgery since implantation. Of the eighty-six ankles, twenty-five ankles (29%) had undergone graft-related reoperations and were considered clinical failures (ten underwent revision allografts, seven underwent arthrodeses, six underwent conversions to total ankle arthroplasty, and two underwent below-the-knee amputations) and eleven ankles (13%) had had reoperations that were not necessarily related to the graft (e.g., implant removal, debridement, synovectomy, or distraction). Survivorship of the osteochondral allograft was 76% at five years and 44% at ten years. The mean Olerud-Molander Ankle Score was 61 points at the time of the latest follow-up. The majority of patients reported satisfaction (92%) with osteochondral allograft transplantation and less pain (85%) and improved function (83%) after the procedure. CONCLUSIONS: Transplantation of a fresh bipolar ankle osteochondral allograft for the treatment of tibiotalar arthritis resulted in acceptable outcomes in this difficult population, with most patients having improved objective and subjective outcome measures. Subjective satisfaction was high in spite of the 29% clinical failure rate. Osteochondral allograft failure did not limit further surgical options. We concluded that transplantation of a bipolar ankle allograft is a useful alternative in carefully selected patients with advanced tibiotalar arthritis.

Mosaicplasty for osteochondral lesions of the talus: a report of two cases.

Two women (24 and 27 years old) noted pain in the affected ankle of several years' duration. Radiography and magnetic resonance imaging revealed osteochondral lesions of the talus in both patients. The lesion sites measured 1.3 × 1.0 × 0.4 cm (0.52 cm(3)) and 2.0 × 1.9 × 0.5 cm (1.9 cm(3)). Each patient received a medial malleolar osteotomy with mosaicplasty. Donor plugs were obtained from the ipsilateral knee in both patients. Surgery was performed successfully in both patients without complications. At 2-year follow-up, both patients had recovered good ankle function, with no donor site morbidity. American Orthopedic Foot and Ankle Society ankle/hindfoot scores improved in the affected ankles from 16 to 84 in case 1 and from 43 to 87 in case 2. Mosaicplasty is effective in treating stage III or IV osteochondral lesions of the talus and results in good-to-excellent recovery of function.

Autologous osteochondral transplantation of the talus partially restores contact mechanics of the ankle joint.

BACKGROUND: Autologous osteochondral transplantation procedures provide hyaline cartilage to the site of cartilage repair. It remains unknown whether these procedures restore native contact mechanics of the ankle joint. PURPOSE: This study was undertaken to characterize the regional and local contact mechanics after autologous osteochondral transplantation of the talus. STUDY DESIGN: Controlled laboratory study. METHODS: Ten fresh-frozen cadaveric lower limb specimens were used for this study. Specimens were loaded using a 6 degrees of freedom robotic arm with 4.5 N·m of inversion and a 300-N axial compressive load in a neutral plantar/dorsiflexion. An osteochondral defect was created at the centromedial aspect of the talar dome and an autologous osteochondral graft from the ipsilateral knee was subsequently transplanted to the defect site. Regional contact mechanics were analyzed across the talar dome as a function of the defect and repair conditions and compared with those in the intact ankle. Local contact mechanics at the peripheral rim of the defect and at the graft site were also analyzed and compared with the intact condition. A 3-dimensional laser scanning system was used to determine the graft height differences relative to the native talus. RESULTS: The creation of an osteochondral defect caused a significant decrease in force, mean pressure, and peak pressure on the medial region of the talus (P = .037). Implanting an osteochondral graft restored the force, mean pressure, and peak pressure on the medial region of the talus to intact levels (P = .05). The anterior portion of the graft carried less force, while mean and peak pressures were decreased relative to intact (P = .05). The mean difference in graft height relative to the surrounding host cartilage for the overall population was -0.2 ± 0.3 mm (range, -1.00 to 0.40 mm). Under these conditions, there was no correlation between height and pressure when the graft was sunken, flush, or proud. CONCLUSION/CLINICAL RELEVANCE: Placement of the osteochondral graft in the most congruent position possible partially restored contact mechanics of the ankle joint. Persistent deficits in contact mechanics may be due to additional factors besides graft congruence, including structural differences in the donor cartilage when compared with the native tissue.

Central talar dome lesions: a unique surgical approach with incorporation of a talar allograft for joint reconstitution and restoration of function.

Osteochondral lesions of the talus have been documented, reported, and studied since as early as the 19th century. The evolution of classification systems has allowed surgeons to better manage osseous lesions. Most osteochondral lesions of the talus have been categorized as anterolateral, posteromedial, or central with respect to the talar dome and its articulating surface. The complexity of the aforementioned lesions each present their own set of obstacles and, hence, management. Specifically, surgery on a central talar dome lesion is complicated by poor exposure and limited access, proving to be a challenging operation. Preoperative planning, including exhaustive imaging before any talar dome surgery, is imperative. We present a case study that involves the need for a distal tibial chevron (wedge) talus, with incorporation of a cadaveric allograft to fill the defect.