Platelet-rich fibrin (PRF) is a natural fibrin meshwork material with multiple functions that are suitable for tissue engineering applications. PRF provides a suitable scaffold for critical-size bone defect treatment due to its platelet cytokines and rich growth factors. However, the structure of PRF not only promotes cell attachment but also, due to its density, provides a pool for cell migration into the PRF to facilitate regeneration. In our study, we used repeated freeze drying to enlarge the pores of PRF to engineer large-pore PRF (LPPRF), a type of PRF that has expanded pores for cell migration. Moreover, a biodegradable Mg ring was used to provide stability to bone defects and the release of Mg ions during degradation may enhance osteoconduction and osteoinduction. Our results revealed that cell migration was more extensive when LPPRF was used rather than when PRF was used and that LPPRF retained the growth factors present in PRF. Moreover, the Mg ions released from the Mg ring during degradation significantly enhanced the calcium deposition of MC3T3-E1 preosteoblasts. In the present study, a bone substitute comprising LPPRF combined with a Mg ring was demonstrated to have much potential for critical-size bone defect repair.

Acetabular or anterior pelvic ring fractures are rare but extremely complicated and challenging injuries for orthopedic trauma surgeons. Three-dimensional (3D) printing technology is widely used in the management of these two fracture types for surgical benefits. Our study aimed to explore whether 3D printing-assisted acetabular or pelvic surgery is beneficial in terms of shortening the length of hospital stay (LHS) and intensive care unit (ICU) stay (ICU LS) for older patients. This retrospective study included two groups of 76 participants over 60 years old who underwent operations with (n = 41) or without (n = 35) guidance by 3D printing. The Mann–Whitney U test was used to analyze continuous variables. Chi-square analysis was applied for categorical variables. Univariable and multivariable linear regression models were used to analyze the factors associated with LHS. The median LHS in the group without 3D printing assistance was 16 (12–21) days, and the median ICU LS was 0 (0–2) days. The median LHS in the group with 3D printing assistance was 17 (12.5–22.5) days, and the median ICU LS was 0 (0–3) days. There was no significant difference in LHS associated with 3D printing assistance vs. that without 3D printing among patients who underwent open reduction and internal fixation for pelvic or acetabular fractures. The LHS positively correlated with the ICU LS whether the operation was 3D printing assisted or not. For fracture surgery in older patients, in addition to the advancement of surgical treatment and techniques, medical teams require more detailed preoperative evaluations, and more personalized medical plans regarding postoperative care to achieve the goals of shortening LHS, reducing healthcare costs, and reducing complication rates.

Interspinous spacers have been designed to provide a minimally invasive surgical technique for patients with lumbar spinal stenosis or foraminal stenosis. A novel pedicle screw-based interspinous spacer has been developed in this study, and the aim of this finite element experiment was to investigate the biomechanical differences between the pedicle screw-based interspinous spacer (M-rod system) and the typical interspinous spacer (Coflex-F™). A validated finite element model of an intact lumbar spine was used to analyze the insertions of the Coflex-F™, titanium alloy M-rod (M-Ti), and polyetheretherketone M-rod (M-PEEK), independently. The range of motion (ROM) between each vertebrae, stiffness of the implanted level, the peak stress at the intervertebral discs, and the contact forces on spinous process were analyzed. Of all three devices, the Coflex-F™ provided the largest restrictions in extension, flexion and lateral bending. For intervertebral disc, the peak stress at the implanted segment decreased by 81% in the Coflex-F™, 60.2% in the M-Ti and 46.7% in the M-PEEK when compared to the intact model. For the adjacent segments, while the Coflex-F™ caused considerable increases in the ROM and disc stress, the M-PEEK only had small changes.

Pelvic and acetabular fractures are challenging for orthopedic surgeons, but 3D printing has many benefits in treating these fractures and has been applied worldwide. This study aimed to determine whether 3D printing can shorten the length of hospital stay (LHS) in nongeriatric male adult patients with these fractures. This is a single-center retrospective study of 167 nongeriatric male adult participants from August 2009 to December 2021. Participants were divided into two groups based on whether they received 3D printing assistance. Subgroup analyses were performed. Pearson’s correlation and multivariable linear regression models were used to analyze the LHS and the parameters. Results showed that 3D printing-assisted surgery did not affect LHS in the analyzed patients. The LHS was positively correlated with the Injury Severity Score (ISS). Initial hemoglobin levels were negatively associated with LHS in patients aged 18–40 and non-major trauma (ISS < 16) patients. In 40–60-year-old and non-major trauma patients, the duration from fracture to admission was significantly associated with LHS. This study indicates that 3D-assisted technology for pelvic or acetabular fracture surgery for nongeriatric male adults does not influence the LHS. More importantly, the initial evaluation of patients in the hospital was the main predictor of the LHS.

Pelvic ring injuries constitute only 2 to 8% of all fractures; however, they occur in 20% of polytrauma patients. High-energy pelvic fractures often result in mechanical instability of the pelvic ring. Successful treatment of unstable pelvic ring fractures remains a challenge for orthopedic surgeons. This study presents a novel internal fixation method for stabilizing unstable anterior pelvic ring fractures using a minimally invasive modified pedicle screw-rod fixation (MPSRF) technique. This retrospective study included six patients with unstable pelvic ring injuries who underwent MPSRF, with or without posterior fixation. Intraoperative parameters such as blood loss, operative time, complications, and quality of reduction (Matta criteria) were recorded and evaluated by a blinded reviewer. In the present clinical series, the mean operative times and mean blood loss for unilateral versus bilateral anterior ring fixations were 176.0 min versus 295.6 min, and 153.3 mL versus 550.0 mL, respectively. No iatrogenic neuropraxia of the lateral femoral cutaneous nerve or femoral nerve palsy occurred. The reduction quality, graded by the Matta criteria, was excellent in five patients and good in one patient. There were no infections, delayed unions, nonunions, or loss of reductions during the follow-up period. Only one patient suffered from a broken rod at 4 months postoperatively. The modified technique represents a novel, minimally invasive procedure for the treatment of anterior pelvic ring fractures and offers a reliable and effective alternative to currently available surgical techniques.