ObjectiveTo investigate the effectiveness of corrective osteotomy for shortened medial foot column after old talar neck fracture.MethodsThe clinical data of 10 patients with shortened medial foot column after old talar neck fracture between June 2012 and May 2017 was retrospectively analyzed. There were 7 males and 3 females with an average age of 45.8 years (mean, 21-67 years). The time from fracture to corrective osteotomy was 9-60 months (mean, 20.9 months). The preoperative visual analogue scale (VAS) score was 7.1±1.2, the American Orthopaedic Foot and Ankle Society (AOFAS) score was 48.5±12.3, and the short-form 36 health survey scale (SF-36) score was 46.7±10.5. All 10 cases received open wedge osteotomy of medial talus. Among them, 2 received subtalar fusion and Achilles tendon lengthening, 2 lateralizing calcaneal osteotomy, and 2 Achilles tendon lengthening.ResultsAll incisions healed by first intention. All patients were followed up 13-72 months (mean, 38.0 months). The X-ray film showed that the angle between longitudinal axis of 1st metatarsal bone and talus increased from (−9.6±4.5) ° before operation to (1.3±2.7) ° at last follow-up (t=16.717, P=0.000); the angle between longitudinal axis of calcaneus and tibia increased from (−12.0±7.4) ° before operation to (−1.5±4.8) ° at last follow-up (t=5.711, P=0.000). At last follow-up, the VAS score, AOFAS score, and SF-36 score were 1.6±1.0, 88.3±5.4, and 85.4±9.2, respectively, which increased significantly when compared with the preoperative scores (t=13.703, P=0.000; t=14.883, P=0.000; t=16.919, P=0.000). X-ray film and CT showed that the osteotomy and arthrodesis sites healed well at 2-4 months after operation.ConclusionIt’s a proper procedure of anatomic reduction and reconstruction for patients with shortened medial foot column and good articular cartilage morphology after old talar fracture. Opening wedge osteotomy of medial talus is recommended and can obtain satisfactory clinical and radiographic results.
ObjectiveTo explore the feasibility of the repair and reconstruction of large talar lesions with three-dimensional (3D) printed talar components by biomechanical test.MethodsSix cadaveric ankle specimens were used in this study and taken CT scan and reconstruction. Then, 3D printed talar component and osteotomy guide plate were designed and made. After the specimen was fixed on an Instron mechanical testing machine, a vertical pressure of 1 500 N was applied to the ankle when it was in different positions (neutral, 10° of dorsiflexion, and 14° of plantar flexion). The pressure-bearing area and pressure were measured and calculated. Then osteotomy on specimen was performed and 3D printed talar components were implanted. And the biomechanical test was performed again to compare the changes in pressure-bearing area and pressure.ResultsBefore the talar component implantation, the pressure-bearing area of the talus varied with the ankle position in the following order: 10° of dorsiflexion > neutral position > 14° of plantar flexion, showing significant differences between positions ( P<0.05). The pressure exerted on the talus varied in the following order: 10° of dorsiflexion < neutral position < 14° of plantar flexion, showing significant differences between positions (P<0.05). The pressure-bearing area and pressure were not significantly different between before and after talar component implantations in the same position (P>0.05). The pressure on the 3D printed talar component was not significantly different from the overall pressure on the talus (P>0.05).ConclusionApplication of the 3D printed talar component can achieve precise repair and reconstruction of the large talar lesion. The pressure on the repaired site don’t change after operation, indicating the clinical feasibility of this approach.