OBJECTIVE: To explore the biomechanical characteristics and clinical application effects of three-dimensional (3D) printed osteotomy guide plate combined with Ilizarov technique in the treatment of rigid clubfoot. METHODS: A retrospective analysis was performed on the clinical data of 11 patients with rigid clubfoot who met the inclusion criteria and were admitted between January 2019 and December 2024. There were 6 males and 5 females, aged 21-60 years with an average of 43.2 years. Among them, 5 cases were untreated congenital rigid clubfoot, 4 cases were recurrent rigid clubfoot after previous treatment, and 2 cases were rigid clubfoot due to disease sequelae. All 11 patients first received slow distraction using Ilizarov technique combined with circular external fixator until the force lines of the foot and ankle joint were basically normal. Then, 1 male patient aged 24 years was selected, and CT scanning was used to obtain imaging data of the ankle joint and foot. A 3D finite element model was established and validated using the plantar stress distribution nephogram of the patient. After validation, the biomechanical changes of the tibiotalar joint under the same load were simulated after triple arthrodesis and fixation. The optimal correction angle of the hindfoot was determined to fabricate 3D-printed osteotomy guide plates, and all 11 patients underwent triple arthrodesis using these guide plates. The functional recovery was evaluated by comparing the American Orthopaedic Foot and Ankle Society (AOFAS) score, International Clubfoot Study Group (ICFSG) score, and 36-Item Short Form Survey (SF-36) score before and after operation. RESULTS: Finite element analysis showed that the maximum peak von Mises stress of the tibiotalar joint was at hindfoot varus 3° and the minimum at valgus 6°; the maximum peak von Mises stress of the 3 naviculocuneiform joints under various conditions appeared at lateral naviculocuneiform joint before operation, and the minimum appeared at lateral naviculocuneiform joint at neutral position 0°; the maximum peak von Mises stress of the 5 tarsometatarsal joints under various conditions appeared at the 2nd tarsometatarsal joint at hindfoot neutral position 0°, and the minimum appeared at the 1st tarsometatarsal joint at valgus 6°. Clinical application results showed that the characteristics of clubfoot deformity observed during operation were consistent with the preoperative 3D reconstruction model. All 11 patients were followed up 8-24 months with an average of 13.1 months. One patient had postoperative incision exudation, which healed after dressing change; the remaining patients had good incision healing. All patients achieved good healing of the osteotomy segments, with a healing time of 3-6 months and an average of 4.1 months. At last follow-up, the AOFAS score, SF-36 score, and ICFSG score significantly improved when compared with those before operation ( P<0.05). CONCLUSION The 3D-printed osteotomy guide plate combined with Ilizarov technique has favorable biomechanical advantages in the treatment of rigid clubfoot, with significant clinical application effects. It can effectively improve the foot function of patients and achieve precise and personalized treatment.
Humans ; Clubfoot/diagnostic imaging* ; Printing, Three-Dimensional ; Male ; Osteotomy/instrumentation* ; Female ; Ilizarov Technique/instrumentation* ; Adult ; Retrospective Studies ; Biomechanical Phenomena ; Middle Aged ; Bone Plates ; Young Adult ; Finite Element Analysis ; Treatment Outcome ; Ankle Joint/physiopathology* ; Tomography, X-Ray Computed ; External Fixators

Purpose: Osteosarcoma (OS) is the most common primary bone tumor, with high morbidity in infants and adolescents. Long noncodingRNA LINC00313 has been found to modulate papillary thyroid cancer tumorigenesis and to be dysregulate in lung cancer.However, the role of LINC00313 in OS has not yet been addressed. Materials and Methods: We evaluated mRNA and protein expression using real-time quantitative PCR and Western blotting. Cellproliferation was evaluated using MTT; apoptosis and autophagy were assessed with flow cytometry, Western blotting, and/orGFP-LC3 assay. Transwell assay was conducted to measure cell migration and invasion. Potential target sites for LINC00313 andmiR-342-3p were predicted with starBase v.2.0 and TargetScan Human, and verified using luciferase reporter assay, RNA immunoprecipitation,and RNA pull-down assay. In vivo, xenogeneic tumors were induced with U2OS and MG-63 cells, separately. Results: LINC00313 was upregulated and miR-342-3p was downregulated in OS tissues and cells. High expression of LINC00313was associated with shorter overall survival. FOSL2 downregulation and miR-342-3p overexpression suppressed cell proliferationand migratory and invasive abilities while promoting apoptosis and autophagy, all of which were consistent with the effects ofLINC00313 knockdown. miR-342-3p, sponged by LINC00313, inversely modulated FOSL2 by targeting MG-63 cells, and FOSL2expression was positively controlled by LINC00313. LINC00313 knockdown suppressed tumor growth in vivo. Conclusion LINC00313 is upregulated in OS, and LINC00313 knockdown plays a vital anti-tumor role in OS cell progressionthrough a miR-342-3p/FOSL2 axis. Our study suggests that LINC00313 may be a novel, promising biomarker for diagnosis andprognosis of OS.