OBJECTIVE: Autologous osteoperiosteal transplantation (AOPT) is one of the most feasible and effective techniques for cystic osteochondral lesions of the talus (OLT). However, few reports have been reported about the process of graft-host bone healing and bone articular surface reconstruction, which help us to further understand the actual situation of bone healing and modify surgical methods.
METHODS: We retrospectively evaluated 33 osteochondral lesions in 30 patients undertaking AOPT for OLT with subchondral cysts from December 2016 to October 2021. According to CT observation, we used 4 variables to describe the bony articular repair, including the integration of the articular surface, the height of the bone filling, the status of bone union, and the appearance of bone resorption or cystic change. We also analyzed the demographic data and clinical function. Descriptive statistics were used for demographic and clinical variables. Normally distributed data were presented as mean ± SD, and non-normally distributed data were presented as median (Q1, Q3). Associations between these variables and the primary clinical outcomes were examined using t-test or one-way ANOVA test for continuous variables.
RESULTS: The patients\' mean age was (41.7 ± 14.0) years old and the mean follow-up time was (29.6 ± 17.8) months. The chondral lesion size was (14.3 ± 4.1) mm. The cyst depth was (10.9 ± 3.7) mm. Significant improvements were observed in functional outcomes (according to the numeric rating scale for pain when walking and the American orthopedic foot and ankle society score) between the preoperative and latest follow-up evaluations, from 4.2 ± 2.1 to 2.2 ± 2.0 (p < 0.001), and from 66.8 ± 12.9 to 83.2 ± 10.4, respectively (p < 0.001). The overall satisfaction reached 8.3 of 10 points. All patients returned to sports and their median daily steps reached 8000 steps with 27 (81.8%) patients walking over 6000 steps daily. According to CT observation, \"discontinuous bony articular surface and gap > 1 mm\" was found in 27 grafts (81.8%), and \"below the level of the adjacent articular surface, ≤ 1 mm\" in a third of the grafts. Abnormal height of bone filling affected numeric rating scale score (p = 0.049) and American Orthopedic Foot and Ankle Society score (p = 0.027). Of note, bone resorption or cystic changes appeared in up to 13 autografts (39.4%).
CONCLUSIONS: AOPT is an effective and acceptable technique for cystic OLT. Bone reconstruction is essential for large cystic OLT. How to get better bony articular reconstruction and avoid cyst recurrence should still be paid more attention.

METHODS: A 15-year-old adolescent girl underwent revision surgery for a posteromedial osteochondral lesion of the talus (OLT). To provide anatomic reduction of her lesion, fluoroscopy and ankle arthroscopy facilitated a transmalleolar tunnel for screw fixation. Now, 8 years after surgery, the patient reports high patient satisfaction and pain-free functional use of her ankle.
CONCLUSIONS: A transmalleolar tunnel technique provides an alternative method to treat posteromedial OLT. This minimally invasive procedure allows patients to be spared potential complications from a medial malleolar osteotomy or a posteromedial incision. Most importantly, this case report demonstrates a positive long-term patient outcome.

OBJECTIVE: This study aimed to evaluate the hypothesis that the utilization of percutaneous screw guides enhances the precision of screw placement in the surgical fixation of talar fractures.
METHODS: Computed tomography (CT) scans of ankle joints were obtained from 40 healthy adults and 10 cadaveric specimens between April 2019 and August 2020 at Ningbo No. 6 Hospital. The acquired CT data were imported into Materialise Interactive Medical Image Control System (MIMICS) software for processing. Three-dimensional (3D) digital models of the ankle joints were reconstructed, and relevant anatomical parameters were measured. A percutaneous screw guide (PSG) was designed and fabricated to facilitate accurate screw placement in the posterior talar process. Ten eligible cadaveric ankle joints were selected for further analysis and their 3D models were reconstructed using the MIMICS software. Screw trajectory parameters were then measured and analyzed based on these cadaveric models, forming the model group for comparative analyses. Ten cadaveric specimens were utilized in this study, equally divided into two groups: a guider group (n = 5) and a free-hand group (n = 5). In the guider group, talar posterior process screws were inserted using percutaneous screw guidance. In the free-hand group, screws were inserted into the talar posterior process without guidance. Post-operative CT scans were performed on all specimens. The following parameters were quantitatively compared between the two groups: screw trajectories, entry point distances in specimens with preselected screws, entry point distance trajectories in the 3D model, operation time, frequency of fluoroscopic imaging, and number of drilling attempts.
RESULTS: Following the generation of the 3D models from 10 cadavers, a virtual screw was digitally inserted into each model. In the model group, the preselected screw trajectory was oriented towards the medial aspect of the talar neck base, with a cephalad inclination angle (CIA) of 3.1° ± 1.5° in the transverse~plane and a medial diverge angle (MDA) of 12.0° ± 1.4° in the coronal plane. The CIA and MDA of the screw trajectory in the guider group were 2.1° ± 1.7° and 11.2° ± 1.6°, respectively, whereas the CIA and MDA in the free-hand group were 6.0° ± 2.2° and 18.8° ± 1.6°, respectively. Statistical analysis revealed significant differences in both CIA and MDA between the two groups (p < 0.05). Furthermore, the guider group yielded superior outcomes in terms of entry point distance, operation time, fluoroscopic exposure time, and number of drilling attempts compared to the free-hand group (p < 0.05).
CONCLUSIONS: Percutaneous screw guidance can improve the accuracy and safety of the posterior process of the talar screws, which can be feasible for percutaneous fixation. Further studies are required to confirm the efficacy and clinical outcomes of percutaneous screw guidance.

New technologies in additive manufacturing and patient-specific CT-based custom implant designs make it possible for previously unimaginable salvage and limb-sparing operations a practical reality. This study presents the design and fabrication of a lattice-structured implant for talus replacement surgery. Our primary case involved a young adult patient who had sustained severe damage to the talus, resulting in avascular necrosis and subsequent bone collapse. This condition caused persistent and debilitating pain, leading the medical team to consider amputation of the left foot at the ankle level as a last resort. Instead, we proposed a Ti6Al4V-based patient-specific implant with lattice structure specifically designed for pan-talar fusion. Finite element simulation is conducted to estimate its performance. To ensure its mechanical integrity, uniaxial compression experiments were conducted. The implant was produced using selective laser melting technology, which allowed for precise and accurate construction of the unique lattice structure. The patient underwent regular monitoring for a period of 24 months. At 2-years follow-up the patient successfully returned to activities without complication. The patient\'s functional status was improved, limb shortening was minimized.

Paediatric talus fracture is an extremely rare type of fracture and occurs due to the structural properties of the elastic cartilage that is resistant to high forces. It has a much lower prevalence than in adults. The axial loading of the talus to the anterior tibia while the ankle is in dorsiflexion is the most common mechanism of talus fractures. Although talus neck fracture is the most common fracture, talus corpus fractures are the second most common. Here we present the case of an adolescent male patient who underwent a successful non-surgical treatment and followup of a neglected talus neck fracture.

BACKGROUND: Total talus dislocation without ankle (malleoli) fracture is a very rare injury with prevalence of only 0.06% of all dislocations and only 2% of talar injuries, and are usually associated with common complications such as infection, avascular necrosis, and posttraumatic arthritis. The treatment usually involves debridement, reduction, stabilization of the ankle joint, and primary or secondary closure of the wound.
METHODS: We present the case of a 40-year-old South Asian woman who was involved in an accident. She was rushed to our hospital, whereby subsequent examination revealed an open total talus dislocation with the talus being exposed in its entirety from a contaminated wound in the medial side. Furthermore, radiograph confirmed total talus dislocation without concomitant malleoli fracture. She was immediately taken to the operating theater whereby debridement and immediate reduction was performed under anesthesia, and the ankle was stabilized with external fixator for about 6 weeks. She is now able to bear weight on the affected ankle with minimal tolerable pain and has normal range of motion of the ankle.
CONCLUSIONS: Open total talus dislocation without concomitant malleoli fracture is a rare injury. Reduction of the talus in combination with complete wound debridement potentially successfully avoids infection, provides early revascularization preventing avascular necrosis, and preserves the normal ankle anatomy.

Background: To investigate the search for an Iliac-Talar Grafts on the iliac bone that is morphologically matched to a multiplanar injury lesion of the talus; while utilizing a bone-harvesting guide to ensure precise positioning of the Iliac-Talar Grafts. Methods: A total of twenty-two cases with both talar CT data and iliac CT data were collected from January 2019 to June 2023. One case each of talar deformity injury and bone disease were excluded, resulting in a selection of 20 cases. The medial and lateral target repair areas of the talus were formulated, and virtual surgery was performed by using digital orthopedic technology to locate an iliac-talar restoration on the iliac bone that matched the morphology of the multiplanar injury lesion of the talus. 3D chromatographic deviation analysis was used to assess the accuracy of Iliac-Talar Grafts in terms of morphometric matching and positioning, while personalized iliac bone extraction guides were designed to ensure accurate positioning of the Iliac-Talar Grafts. Results: The best fitting point for repairing the medial talar lesion is determined to be medial to the anterior iliac crest, specifically 2.935 ± 0.365 cm posterior to the anterior superior iliac spine, and 2.550 ± 0.559 cm anterior to the valgus-iliac crest point (VICP). Similarly, for the repair of the lateral talar lesion, the ideal position is found to be lateral to the posterior iliac crest, approximately 2.695 ± 0.640 cm posterior to the valgus-iliac crest point (VICP). Utilizing bone extraction guides enables precise positioning for iliac bone extraction. Conclusion: This study utilizes virtual surgery, 3D chromatographic deviation analysis, and guide plate techniques in digital orthopedics to precisely locate the Iliac-Talar Graft on the iliac bone, matching the morphology of the talar lesion; it provides a new solution for cutting the iliac bone implant that matches the the multifaceted talar lesion to be repaired.

Anterior talofibular ligament injuries and osteochondral lesions of the talus present unique challenges to orthopedic surgeons. This study aimed to investigate the relevant relationship between them by analyzing the Magnetic resonance imaging (MRI) results of clinical patients and single-cell RNA sequence (scRNA seq) results of healthy talus cartilage to discuss the risk factors. Data from 164 patients from 2018 to 2023 was retrospectively analyzed. The correlation analysis between ATFL injury grade and the Hepple stage of OLT determined by MRI was performed. Publicly available single-cell RNA datasets were collected. Single-cell RNA datasets from five volunteers of healthy talus cartilage were analyzed. ATFL injury grade was relevant with the Hepple stage of OLT (P < 0.05). The results of multivariate logistic regression analysis showed that injured area was the independent influencing factor of the incidence rate and the severity of OLT (P < 0.05). The Hepple stage of OLT was relevant with AOFAS and VAS (P < 0.05). Single-cell RNA sequence results showed that among the 9 subtypes of chondrocytes, the interaction strength between HTC-A and HTC-B is the highest. Their physical interactions are mainly achieved through the CD99 signaling pathway, and factor interactions are mainly achieved through the ANGPTL signaling pathway. Anterior talofibular ligament injury may lead to osteochondral lesions of the talus. Early medical intervention should be carried out for ligament injuries to restore joint stability and avoid cartilage damage.

En bloc resection is required for treatment of intermediate-grade talar tumors with extraosseous extension (Enneking stage 3) and malignant talar tumors without intra-articular invasion (Enneking stages IA and IIA). After resection, reconstruction options include tibiocalcaneal fusion, frozen autograft, and talar prosthesis; however, a talar prosthesis is preferable because it preserves ankle range of motion, does not cause leg length discrepancy, and is associated with good long-term outcomes. To the best of our knowledge, en bloc resection and reconstruction of a malignant talar tumor has not been previously reported in detail. We report a detailed surgical technique for en bloc resection of a malignant talar bone tumor using combined anterior and lateral approaches followed by reconstruction using a talar prosthesis.

BACKGROUND: Talar neck non-unions result in significant hindfoot deformity and morbidity and are infrequently reported in the literature. The optimal surgical management for this condition is evolving, with various authors reporting the results of open reduction and internal fixation (ORIF) with bone grafting (BG), ankle fusion and modified Blair fusion. We performed this study to report the clinical and radiological outcomes of a cohort of talar neck non-unions managed by ankle joint preserving reconstruction.
METHODS: This was an ambispective study which included 8 patients (7 male and 1 female) with talar neck non-unions. All patients underwent ORIF+BG through dual approaches. Additional medial malleolar osteotomy was done in 2 cases, and calcaneofibular split approach to the subtalar joint in 3. Adjunct subtalar fusion was done in 5 cases. Clinical and radiological evaluation was performed pre- and post-operatively. Functional outcomes were assessed by the Manchester Oxford Foot Questionnaire (MOxFQ).
RESULTS: The mean age of patients 32.3 ± 13.1 years. The mean surgical delay was 4.1 ± 1.7 months. As per Zwipp and Rammelt classification of post-traumatic talar deformities, 5 cases were classified as Type 3, 2 were Type 4, and 1 was Type 1. Union was achieved in 7 cases at a mean of 3.4 ± 1.3 months. One case had progressive collapse, which was managed by pantalar arthrodesis. All 3 cases where subtalar fusion was not performed primarily demonstrated subtalar arthrosis, but none required a secondary subtalar fusion. The MOxFQ score from 61.1 ± 10.1 to 41 ± 14.1 postoperatively (P = 0.005). The mean follow-up was 14.6 ± 6.8 months.
CONCLUSIONS: ORIF+BG of the talar neck, with or without subtalar fusion has the potential to achieve solid union, correct the hindfoot deformity and improve functional outcomes. However, larger studies with longer follow-up are needed to evaluate the long-term efficacy of this procedure.