Reconstructing extensive cranial defects represents a persistent clinical challenge. Here, we reported a hybrid three-dimensional (3D) printed scaffold with modification of QK peptide and KP peptide for effectively promoting endogenous cranial bone regeneration. The hybrid 3D printed scaffold consists of vertically aligned cryogel fibers that guide and promote cell penetration into the defect area in the early stages of bone repair. Then, the conjugated QK peptide and KP peptide further regulate the function of the recruited cells to promote vascularization and osteogenic differentiation in the defect area. The regenerated bone volume and surface coverage of the dual peptide-modified hybrid scaffold were significantly higher than the positive control group. In addition, the dual peptide-modified hybrid scaffold demonstrated sustained enhancement of bone regeneration and avoidance of bone resorption compared to the collagen sponge group. We expect that the design of dual peptide-modified hybrid scaffold will provide a promising strategy for bone regeneration.

Background: Surgical treatment of both-column acetabular fractures is challenging because of the complex acetabular fracture patterns and the curved surface of the acetabulum. Seldom study has compared the application of three-dimensional (3D) printing technology and traditional methods of contouring plates intra-operatively for the surgical treatment of both-column acetabular fractures. We presented the use of both 3D printing technology and a virtual simulation in pre-operative planning for both-column acetabular fractures. We hypothesized that 3D printing technology will assist orthopedic surgeons in shortening the surgical time and improving the clinical outcomes. Methods: Forty patients with both-column acetabular fractures were recruited in the randomized prospective case–control study from September 2013 to September 2017 for this prospective study (No. ChiCTR1900028230). We allocated the patients to two groups using block randomization (3D printing group, n = 20; conventional method group, n = 20). For the 3D printing group, 1:1 scaled pelvic models were created using 3D printing, and the plates were pre-contoured according to the pelvic models. The plates for the conventional method group were contoured during the operation without 3D printed pelvic models. The operation time, instrumentation time, time of intra-operative fluoroscopy, blood loss, number of times the approach was performed, blood transfusion, post-operative fracture reduction quality, hip joint function, and complications were recorded and compared between the two groups. Results: The operation and instrumentation times in the 3D printing group were significantly shorter (130.8 ± 29.2 min, t = −7.5, P < 0.001 and 32.1 ± 9.5 min, t = −6.5, P < 0.001, respectively) than those in the conventional method group. The amount of blood loss and blood transfusion in the 3D printing group were significantly lower (500 [400, 800] mL, Mann-Whitney U = 74.5, P < 0.001 and 0 [0,400] mL, Mann-Whitney U = 59.5, P < 0.001, respectively) than those in the conventional method group. The number of the approach performed in the 3D printing group was significantly smaller than that in the conventional method group (pararectus + Kocher-Langenbeck [K-L] approach rate: 35% vs. 85%; χ ² = 10.4, P < 0.05). The time of intra-operative fluoroscopy in the 3D printing group was significantly shorter than that in the conventional method group (4.2 ± 1.8 vs. 7.7 ± 2.6 s; t = −5.0, P < 0.001). The post-operative fracture reduction quality in the 3D printing group was significantly better than that in the conventional method group (good reduction rate: 80% vs. 30%; χ ² = 10.1, P < 0.05). The hip joint function (based on the Harris score 1 year after the operation) in the 3D printing group was significantly better than that in the conventional method group (excellent/good rate: 75% vs. 30%; χ ² = 8.1, P < 0.05). The complication was similar in both groups (5.0% vs. 25%; χ ² = 3.1, P = 0.182). Conclusions: The use of a pre-operative virtual simulation and 3D printing technology is a more effective method for treating both-column acetabular fractures. This method can shorten the operation and instrumentation times, reduce blood loss, blood transfusion and the time of intra-operative fluoroscopy, and improve the post-operative fracture reduction quality. Clinical trail registration: No.ChiCTR1900028230; http://www.chictr.org.cn

Objective: To investigate the relationship between the infection rate and the timing of replacement of temporary external fixators with internal fixation, and the timing of immediate or delayed internal fixation after removal of temporary external fixation in the staging treatment modality of open fractures of extremities. Methods: A retrospective analysis was performed on 122 cases of open fractures of extremities. External fixators were applied at the early stage and replaced with internal fixation when the condition of soft tissues improved and inflammatory indexes dropped to the normal range or showed a steady downward trend. Depending on the carrying time of external fixators after wound closure or healing, the patients were divided into three groups; the carrying time of groups A, B, and C was ≤ 14 days, 15–28 days, and > 28 days, respectively. Depending on the immediate or delayed internal fixation after removal of external fixator, patients were divided into group a (immediate internal fixation after removal of external fixator) and group b (delayed internal fixation after removal of external fixator, 5–7 days later). Results: The infection rates of groups A, B, and C were 6.5%, 5.9%, and 23.3%, respectively. The differences among the three groups were statistically significant (P < 0.05). The infection rates of different Gustilo–Anderson fractures were as follows: no cases of infection out of 10 cases with type I fracture (0%); two cases of infection out of 35 cases with type II fracture (5.7%); three cases of infection out of 36 cases with IIIa fracture (8.3%); five cases of infection out of 28 cases with IIIB fracture (17.9%); and five cases of infection out of 13 cases with IIIC fracture (38.5%). The differences among the five groups were statistically significant. Conclusions: The occurrence of infection of open fractures of extremities is associated with the fracture severity (Gustilo classification). For open fractures of Gustilo types I and II, the final internal fixation should be placed as soon as possible when the recovery of general and local conditions is good and the infection is controlled.

Objective: The effectiveness of autologous osteoperiosteal transplantation (AOPT) for the treatment of large cystic talar osteochondral lesions (OCLs) should be further evaluated, and the postoperative cartilage coverage is questionable. The purpose of this retrospective observational study was to investigate the clinical outcomes of AOPT for the treatment of large cystic talar OCLs and to report second‐look arthroscopic results.Methods: From June 1, 2017, to June 1, 2021, all talar OCLs at our center were reviewed. Painful cystic lesions treated with AOPT were included in the study. The American Orthopaedic Foot and Ankle Society (AOFAS; 0–100 points) ankle‐hindfoot score, Foot Function Index (FFI; 0–100 points), visual analog scale (VAS; 0–10 points) score, and Tegner score (0–10 points) were used to describe pain and functional outcomes. Furthermore, complications, patient‐reported satisfaction degrees, imaging results (including computed tomography and magnetic resonance), and second‐look arthroscopic evaluation data were also collected for analysis.Results: A total of 29 cases were eligible for the study, and 26 responded to the latest follow‐up request, with a mean follow‐up duration of 30.2 (range, 12–57) months. The AOFAS score improved from 69.2 ± 10.9 preoperatively to 80.9 ± 10.0 at the latest follow‐up (p = 0.000). The FFI score improved from 30.4 ± 18.4 preoperatively to 16.3 ± 14.0 at the latest follow‐up (p = 0.000). The VAS pain score improved from 4.0 ± 2.1 preoperatively to 2.5 ± 2.0 at the latest follow‐up (p = 0.001). No donor site morbidity was found. The mean postoperative MOCART score was 57.7 ± 9.5. Second‐look arthroscopy showed a fibrillated cartilage‐like surface at the lesion site in most cases, while two cases exhibited a nearly normal surface.Conclusion: The transplantation of osteoperiosteal cylinder autografts taken from the iliac crest for the treatment of large cystic talar OCLs yielded acceptable clinical results. Good integration of the bony part was observed, but cartilage regeneration remained uncertain.

Background: Recent studies have reported the vital roles of circular RNAs (circRNAs) in tumor progression. However, the function and expression profile of most circRNAs in osteosarcoma remain unclear. Methods: We examined the expression of circEPSTI1, a circRNA, in 50 paired adjacent normal tissues and osteosarcoma tissues by qRT-PCR. Then, we further explored the function of circEPSTI1 in osteosarcoma progression in vitro and in vivo. For example, cell proliferation and migration were examined. Some experiments were performed to explore the regulatory function of circEPSTI1 in miRNA and to investigate the potential role of circEPSTI1 in osteosarcoma. Results: We found that circEPSTI1 was significantly upregulated in osteosarcoma. Inhibition of circEPSTI1 suppressed the osteosarcoma cancer cell proliferation and migration in vitro. Dual luciferase reporter assay showed that circEPSTI1 and MCL1 (myeloid cell leukaemia 1) could bind to miR-892b and that MCL1 and circEPSTI1 were targets of miR-892b. Conclusion: Thus, the circEPSTI1-miR-892b-MCL1 axis affected osteosarcoma progression through the miRNA sponging mechanism. circEPSTI1 may serve as a target and biomarker for osteosarcoma treatment.