A minimally invasive spherical osteotomy assistant system (MISOS) based on a multi-axis surgical robot was designed to improve the control and precision of manual spherical osteotomy.

Based on human sawbone models, the feasibility of MISOS was verified by comparing the osteotomy centre deviation and the section curvature of the acetabulum, femur, and tibia.

Compared with freehand spherical osteotomy, the MISOS system demonstrated superior centre deviation for the acetabulum (1.48 ± 0.93 vs. 11.15 ± 3.97 mm), femur (3.12 ± 0.75 vs. 8.81 ± 3.04 mm), and tibia (1.91 ± 0.84 vs. 7.33 ± 1.53 mm) as well as superior curvature deviation for the acetabulum (1.40 ± 0.08 vs. 3.16 ± 0.56 mm), femur (0.26 ± 0.07 vs. 0.491 ± 0.21 mm), and tibia (0.21 ± 0.02 vs. 0.46 ± 0.18 mm). These results indicate that MISOS can assist surgeons in performing accurate and stable spherical osteotomy.

The MISOS system demonstrates promise as a precise assistive tool for minimally invasive orthopaedic spherical osteotomy, with potential for broader clinical applications.

Uncontrollable bleeding and tissue defects caused by trauma are significant clinical issues. Apoptotic vesicles (apoVs) derived from mesenchymal stem cells (MSCs) have shown promise for hemostasis and tissue regeneration, but their clinical safety and efficacy remain unverified. We investigated the procoagulant and regenerative function of lyophilized MSC-derived apoVs (MSC-apoVs) using in vitro experiments and in vivo rat models. In addition, we conducted a double-blind, randomized, self-controlled clinical trial to evaluate the safety and efficiency of lyophilized MSC-apoVs for hemostasis and bone regeneration following extraction of impacted mandibular third molars. We show that lyophilized MSC-apoVs maintain their procoagulant and regenerative functions after storage at 4°C for 3 months and upregulate tripartite motif containing 71 to activate the extracellular signal-regulated kinase signaling pathway. Furthermore, among the 43 enrolled subjects, 39 patients completed all follow-ups and 4 patients were lost to contact. All 39 patients tolerated MSC-apoVs well, with no serious adverse events or abnormal blood test results observed. The MSC-apoV group exhibited shortened hemostatic time and accelerated alveolar bone regeneration compared with the control group. This is the first clinical study to demonstrate that apoVs are safe, well tolerated, and effective as a cell-free biological therapy for hemostasis and bone regeneration.

Pelvic support osteotomy (PSO) is regarded to provide pelvic stability and improve abductor function to delay or even avoid total hip arthroplasty (THA) in young patients with high-riding hip dysplasia. However, some of these patients eventually have to undergo THA. Because of the double-angulation deformity of the femur after PSO, subsequent THA is challenging. This study aimed to analyze whether PSO surgery is suitable for high-riding hip dysplasia and summarize orthopaedic strategy during THA for patients with previous PSO.

This case-control study included eight cases of THA for high-riding hip dysplasia patients with previous PSO (study group) and 24 cases of high-riding hip dysplasia patients without any hip surgical therapy (control group) by a 1:3 match (from May 2018 to January 2022). We compared demographics and joint function before and after THA between two groups and recorded all patients' preoperative imaging data, surgical procedures, postoperative imaging data, and complications. The surgical techniques for patients with previous PSO were highlighted.

There was no statistical difference between the two groups in demographic (p > 0.05). The study group had worse hip Harris score (HHS), range of motion (ROM), visual analogue scale (VAS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) (p < 0.05) compared with the control group before THA. All patients had concurrent THA and osteotomy at the proximal femur, but the study group experienced longer operation time (p = 0.047) with more blood loss (p = 0.027) and higher complication rate compared with the control group (p = 0.009). At the last follow-up, the study group's HHS, ROM, VAS, and WOMAC were still worse than those in the control group.

PSO did not improve the joint function of high-riding hip dysplasia patients but brought challenges to subsequent THA and affected the surgical outcomes. In short, we suggested that PSO is unsuitable for routine high-riding hip dysplasia patients.

The Ilizarov technique has been continuously innovated to utilize tensile stress (TS) for inducing a bone development-like regenerative process, aiming to achieve skeletal elongation and reconstruction. However, it remains uncertain whether this distraction osteogenesis (DO) process induced by TS involves the pivotal coupling of angiogenesis and osteogenesis mediated by type H endothelial cells (THECs). In this study, it is demonstrated that the Ilizarov technique induces the formation of a metaphysis-like architecture composed of THECs, leading to segmental bone regeneration during the DO process. Mechanistically, cell-matrix interactions-mediated activation of yes-associated protein (YAP)/transcriptional co-activator with PDZ-binding motif (TAZ) transcriptionally upregulates the expression of Notch1 and Delta-like ligand 4, which act as direct positive regulators of THECs phenotype, in bone marrow endothelial cells (BMECs) upon TS stimulation. Simultaneously, the Notch intracellular domain enhances YAP/TAZ activity by transcriptionally upregulating YAP expression and stabilizing TAZ protein, thus establishing the YAP/TAZ-Notch circuit. Additionally, TS-stimulated BMECs secrete exosomes enriched with vital molecules in this positive feedback pathway, which can be utilized to promote segmental bone defect healing, mimicking the therapeutic effects of Ilizarov technique. The findings advance the understanding of TS-induced segmental bone regeneration and establish the foundation for innovative biological therapeutic strategies aimed at activating THECs.

The Ilizarov method is one of the current methods used in bone reconstruction. It originated in the middle of the past century and comprises a number of bone reconstruction techniques executed with a ring external fixator developed by Ilizarov GA. Its main merits are viable new bone formation through distraction osteogenesis, high union rates and functional use of the limb throughout the course of treatment. The study of the phenomenon of distraction osteogenesis induced by tension stress with the Ilizarov apparatus was the impetus for advancement in bone reconstruction surgery. Since then, the original method has been used along with a number of its modifications developed due to emergence of new fixation devices and techniques of their application such as hexapod external fixators and motorized intramedullary lengthening nails. They gave rise to a relatively new orthopedic subspecialty termed "limb lengthening and reconstruction surgery". Based on a comprehensive literature search, we summarized the recent clinical practice and research in bone reconstruction by the Ilizarov method with a special focus on its modification and recognition by the world orthopedic community. The international influence of the Ilizarov method was reviewed in regard to the origin country of the authors and journal's rating. The Ilizarov method and other techniques based on distraction osteogenesis have been used in many countries and on all populated continents. It proves its international significance and confirms the greatest contribution of Ilizarov GA to bone reconstruction surgery.

To evaluate the effectiveness of modified Ilizarov hip reconstruction in the treatment of hip instability.

The clinical data of 13 young patients with hip diseases treated with modified Ilizarov hip reconstruction between January 2010 and March 2018 were retrospectively analyzed. There were 2 males and 11 females, aged from 14 to 34 years, with an average age of 24.2 years. There were 1 case of hip dysplasia and dislocation due to spinal bifida, 3 cases of hip dysplasia after pyogenic arthritis of the hip, 2 cases of developmental dysplasiaof the hip (DDH) accompanying femoral head necrosis who rejected hip replacement, 6 cases of young DDH refused to undergo hip replacement, and 1 case of bilateral hip dysplasia with dislocation due to sputum cerebral palsy. The disease duration was 2-20 years, with an average of 8.5 years. Preoperative Trendelenburg sign was positive in 12 cases and negative in 1 case. The preoperative Harris score of hip joint was 53.5±8.9 and the unequal length of lower limbs was (46.08±15.73) mm. Postoperative Harris hip score and patients' satisfaction with effectiveness evaluated according to their self scoring were used to assess the effectiveness.

All 13 patients were followed up 1-5 years, with an average of 2.6 years. Five patients developed postoperative needle infection, which improved after dressing change; 7 patients had limited knee joint activity and improved after knee joint function training. The Trendelenburg sign was negative at 1 year after operation, and the patient's hip pain symptoms were relieved or disappeared. The Harris hip score of patients at 1 year after operation was 84.5±6.1, which was significantly improved when compared with preoperative one ( t=－10.538, P=0.000). According to Harris hip score, the effectiveness results were excellent in 4 cases, good in 5 cases, and fair in 4 cases, with an excellent and good rate of 69.2%. The unequal length of lower limbs was (15.38±7.27) mm, which was significantly better than that before operation ( t=11.826, P=0.000). At last follow-up, the patients' satisfaction score was 80%-95%, with an average of 88%.

Modified Ilizarov hip reconstruction can be used to treat young patients with hip disease who are unsuitable or refuse to undergo artificial hip replacement. Its effectiveness is reliable, and it has unique advantages in limb limp improvement and limb shortening correction.