Journal of Orthopaedic Research®最新文献

Musculoskeletal infection (MSKI) remains a major problem after trauma and elective orthopedic surgery. Chronic MSKI is related to the formation of biofilm, which impairs diagnosis and effective treatments. Therefore, to understand and communicate global standards and best practices, the 2025 International Consensus Meeting (ICM) on MSKI created a Biofilm Section to address crucial aspects of biofilm biology pertaining to its mechanisms of drug resistance and immune evasion, and potential approaches to overcome them. This featured a 2-year process, with final voting and discussion on May 8–10, 2025, in Istanbul, Turkey. This Consensus Article is the effort of the Biofilm Basic Mechanisms Workgroup, which interpreted the results on ICM questions related to (1) the infectious microenvironment; (2) appropriate inocula in preclinical research; (3) biofilm behavior in infected tissues; and (4) synergy within biofilms and with other comorbidities. Collectively, we find that this field has the necessary research tools to discover the pathophysiology of orthopedic implant-associated biofilm development and maturation, perform clinically relevant studies in animal models, and elucidate mechanisms that allow opportunistic infections in compromised tissues and patients with other health issues.

Ceramic-on-ceramic hip resurfacing arthroplasty (CoC-HRA) has been developed to eliminate metal ion concerns which have been associated with metal-on-metal hip resurfacing arthroplasty (MoM-HRA) while maintaining similar functionality. The aim of the study was to examine gait function pre- and postoperatively between CoC-HRA, MoM-HRA, and THA using subjective and objective measures with comparison to a healthy control group. Nineteen unilateral CoC-HRA, 19 unilateral MoM-HRA, and 18 unilateral THA gender, age, and BMI matched participants completed patient-reported outcome measures (PROMs) (Oxford hip score [OHS] and metabolic equivalence of task score [MET]) and underwent gait analysis on an instrumented treadmill, preoperatively (2–8 weeks) and then postoperatively (40–52 weeks). Spatiotemporal measures and vertical ground reaction forces (GRF) were recorded. Statistical parametric mapping was used to detect differences in GRF between affected and nonaffected leg and to healthy controls. Preoperatively, there were no differences between groups in PROMs or objective measures. All groups showed an improved OHS postoperatively with only CoC-HRA and MoM-HRA demonstrating significant increase in MET. Postoperatively, TWS in both HRA groups improved with no difference to CON while THA was unable to demonstrate improvements. Postoperatively, at 6.5 km/h, THA demonstrated an asymmetric GRF profile, whereas CoC-HRA and MoM-HRA showed no differences between legs. In comparison of the affected leg GRF, THA demonstrated a weaker push off when compared to both resurfacing groups and CON. CoC-HRA and MoM-HRA showed no significant differences to CON. CoC-HRA emerges as a potential alternative to MoM-HRA, effectively addressing metal ion release concerns while retaining similar functional benefits.

Premature physeal closure occurs following trauma, cancer, or infection. Current treatments have poor success rates. With recent pediatric donor tissue availability, physeal allograft transfer (PAT) can now be considered. The purpose of this study was to study the safety and feasibility of PAT in a large animal model. The aim of this study is to gather foundational data to inform future studies into the efficacy of PAT. Physeal defects were created in the distal femur of nine female domestic swine and treated with PAT from two male donor pigs, cementation, or bone autograft. Viability was assessed. After 3 months, physes were visualized using CT and MRI. Integration, tissue composition, donor DNA presence, and microscopic appearance were evaluated. Physeal allografts demonstrated 93% viability after procurement and preservation. All animals reached the 3-months study endpoint without gross deformations. No physeal bars formed in any group. Cystic changes were seen in experimental and control femurs. All groups showed disorganized tissue architecture without growth plate recapitulation. High allografts viability and structural integrity after procurement support the potential of this treatment. Although no gross deformities were found, transferred physes demonstrate poor integration and incomplete repair. The lack of physeal bar formation in the control group limits the reliability of the animal model for studying physeal allograft transfer. Lastly, this study was designed as a feasibility study and lacks power to compare treatment effects statistically. The efficacy of PAT for preventing growth arrest remains undetermined.

Injury to the anterior cruciate ligament (ACL) is common in young, active individuals. It has the potential to lead to post-traumatic osteoarthritis. However, the effects of ACL injury on the bio-composition and microstructure of the knee's collateral ligaments have been poorly explored. In this study, Fourier transform infrared (FTIR) imaging and quantitative polarized light microscopy (qPLM) were used to identify the respective changes in bio-composition and collagen fiber arrangements of the knee's collateral ligaments. To mimic an ACL trauma, unilateral ACL transection surgery was performed on either the left or right knee of 6 mature New Zealand white rabbits. Lateral and medial collateral ligaments were harvested from the transected and contralateral knees 8 weeks after the ACL transection surgery. At the same time, collateral ligaments of 4 age-matched, healthy rabbits were collected from the right and left knees. From acquired FTIR images, the relative collagen and proteoglycan contents of the collateral ligaments were estimated and compared between the transected, contralateral, and control knees. The results revealed lower collagen and higher proteoglycan content in ACL-transected collateral ligaments compared to collateral ligaments of contralateral and control group knees. Additionally, qPLM revealed a more disorganized collagen fiber matrix, accompanied by increased crimp angles and longer crimp lengths following ACL transection. This study provides novel insight into the bio-compositional and microstructural alterations of collateral ligaments following ACL injury, highlighting the importance of considering the structure-function properties of collateral ligaments in treatment planning aimed at restoring normal knee joint function after ACL injury.

The study aimed to compare contact stresses for a novel lumbar total joint replacement (LTJR) during a standardized duty cycle with elevated loading conditions. A finite element model (FEM) of an LTJR was developed, verified, and validated using the ASME V&V40 standard. Simulations were performed using LS-Dyna. Increasing the axial loading for the 95th percentile male generally resulted in an increase in the peak contact pressures throughout the duty cycle. Specifically, contact pressure reached a maximum of 37.6 MPa. Despite this increase, the polyethylene peak contact stresses remained considerably lower than values previously documented during impingement. For 95th percentile male loading, the bearing mechanics of the LTJR design remained reasonably consistent with the 50th male loading scenario. Contact between the superior and inferior components remained confined to the intended hemispherical bearing surfaces, without evidence of impingement. The contact stresses in elevated loading scenarios fell below the levels associated with impingement loading. The polyethylene bearing stresses indicate that relative risks of wear and surface damage, including pitting, delamination, and fracture associated with a 95th percentile male, will be lower relative to the conditions from impingement testing.

Clinical Significance: Our in silico approach to exploring elevated boundary conditions for spine wear testing will facilitate future test method development.

Advancements in computer-assisted navigation, robotics, and augmented reality (AR) are transforming orthopaedic surgery by enhancing precision, safety, and effectiveness. This systematic review summarizes 39 peer-reviewed publications from 2015 to 2025 that utilized next-generation surgical systems to perform total hip arthroplasty (THA), total knee arthroplasty (TKA), spinal procedures, trauma fixation, and oncologic resections. The methodological quality of included manuscripts was assessed using the Methodological Index for Non-Randomized Studies (MINORS), allowing quantitative evaluation of study rigor and risk of bias. It was found that the use of navigation, robotic systems, and AR in the operating room has resulted in improved implant accuracy and precision. When reported, long-term clinical outcomes still show nominal differences compared to conventional surgical approaches, although short-term improvements such as pain relief and recovery timelines have been demonstrated in select cases. MINORS scoring revealed relatively high methodological quality across platform technologies. Despite promising results, substantial challenges need to be met prior to more widespread adoption, including lowering economic costs, shortening learning curves, and improving integration into clinical workflows.

Chronic ankle instability (CAI) can develop in up to 40% of patients after a first-time ankle sprain. Advanced imaging and statistical shape modeling (SSM) provide the opportunity to evaluate if subtle differences in foot and ankle morphology, such as hindfoot alignment or cavus features, may contribute to structural predispositions for recurrent instability. In this study, a 14-bone SSM was created from weight-bearing CT data (n = 80) from patients with CAI (n = 23), cavus foot type (n = 29), and rectus (n = 28) foot type. Scans for the CAI group were from pre-operative imaging of patients undergoing surgical stabilization. Meary's angle (MA), hindfoot ankle alignment (HAA), and calcaneal inclination were measured for each scan using in-house code. Principal component analysis revealed that arch height (Mode 1, 36.9% of the variance) statistically distinguished the CAI and cavus groups from the rectus group. Minimal differences were observed between the CAI and cavus groups, with only Mode 5 (4.47% variance, $��\; ��{\eta }^2��$ = 0.09) separating the groups and Hotelling's T² confirming minimal variation (~2% of particles). Radiographic measurements supported these findings with higher MA in CAI (12°) and cavus (17°) versus rectus (0.2°), and varus HAA in CAI (6.0°) and cavus (5.9°) compared to rectus (9.8°). Individuals with CAI demonstrated cavus-like morphology, indicating that bony alignment may be a structural contributor to recurrent instability. Clinically, these findings enhance our understanding that foot alignment plays a role in CAI. Surgical correction, when clinically appropriate, may need to address both osseous deformities and soft tissue laxity to improve stability. Level III Orthopedic Research Society.

The purpose of the study was to examine the effects of a biofeedback intervention on limb stiffness and eccentric knee joint power (ECCKP) symmetry, as well as related landing biomechanics, in individuals post-anterior cruciate ligament reconstruction (ACLR). Thirty-three participants (Biofeedback: n = 14; Control: n = 19) completed a 12-week protocol with assessments at baseline, post-intervention, and retention time-points. Linear mixed-effects models evaluated the effects of group and time-point on ECCKP normalized symmetry index (NSI) and limb stiffness NSI. Linear mixed-effects models evaluated the effects of group, time-point, and limb (surgical vs. non-surgical) on limb stiffness, peak relative ground reaction force (rGRF), change in limb length, and time to peak rGRF during landing. There were no significant group × time-point interactions found for ECCKP NSI or limb stiffness NSI (p > 0.05). For limb stiffness, the non-surgical limb showed greater stiffness (p = 0.001). Peak rGRF was higher in the non-surgical limb (p = 0.001) and at baseline compared to post-intervention (p = 0.023). Time to peak rGRF was longer in the non-surgical limb (p = 0.008). No significant effects were found for change in limb length. Overall, the biofeedback intervention did not significantly improve ECCKP or limb stiffness symmetry post-ACLR. Persistent symmetry deficits in landing biomechanics were evident, particularly between surgical and non-surgical limbs. Given that the study was likely underpowered to detect moderate effects, findings should be interpreted with caution. Larger, adequately powered studies are warranted to further evaluate the effect of biofeedback in improving symmetry during dynamic tasks after ACLR.

Trial Registration: ClinicalTrials.gov: AR069865.