A 3D geometric morphometric analysis of the bovid distal humerus, with special reference to Rusingoryx atopocranion (Pleistocene, Eastern Africa).

The family Bovidae [Mammalia: Artiodactyla] is speciose and has extant representatives on every continent, forming key components of mammal communities. For these reasons, bovids are ideal candidates for studies of ecomorphology. In particular, the morphology of the bovid humerus has been identified as highly related to functional variables such as body mass and habitat. This study investigates the functional morphology of the bovid distal humerus in isolation due to its increased likelihood of preservation in the fossil record, and the resulting opportunity for a better understanding of the ecomorphology of extinct bovids. A landmark scheme of 30 landmarks was used to capture the 3D distal humerus morphology in 111 extant bovid specimens. We find that the distal humerus has identifiable morphologies associated with body mass, habitat preference and tribe affiliation and that some characteristics are shared between high body mass bovids and those living on hard, flat terrain which is likely due to the high stress on the bone in both cases. We directly apply our findings regarding extant bovids to the extinct alcelaphine bovid, Rusingoryx atopocranion from the mid to late Pleistocene (>33-45 ka) Lake Victoria region of Kenya. This species is known for some peculiar morphologies including a domed cranium with hollow nasal crests, and having small hooves for a bovid of its size. Another interesting aspect of Rusingoryx's skeletal morphology which has not been addressed is an unusual protrusion on the lateral epicondyle of the distal humerus. Despite considerable individual variation in the Rusingoryx specimens, we find evidence to support its historical assignment to the tribe Alcelaphini, and that it likely preferred open grassland habitats, which is consistent with independent reconstructions of the palaeoenvironment. We also provide the most accurate body mass estimate for Rusingoryx to date, based on distal humerus centroid size. Overall, we are able to conclude that the distal humerus in extant bovids is highly informative regarding body mass, habitat preference and tribe, and that this can be applied directly to a fossil taxon with promising results.

Transcriptome sequencing reveals inflammation and macrophage heterogeneity in subacromial bursa from degenerative shoulder disorders.

PURPOSE: We aimed to investigate the transcriptomic alterations that occur in the subacromial bursa (SAB) following degenerative or traumatic shoulder diseases. MATERIALS AND METHODS: RNA sequencing was employed to evaluate the transcriptomic alterations of the SAB in individuals afflicted with degenerative rotator cuff tear (RCT), traumatic RCT and proximal humerus fracture (PHF). To gain insights into the biological significance of differentially expressed genes (DEGs), we conducted an enrichment analysis utilizing Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. We further utilized single-cell RNA sequencing datasets of SAB from a recently published study to explore the associated cellular dynamics and alterations. RESULTS: We detected 1,790 up-regulated and 1,964 down-regulated DEGs between degenerative RCT and PHF, 2,085 up-regulated and 1,919 down-regulated DEGs between degenerative RCT and traumatic RCT, and 20 up-regulated and 12 down-regulated DEGs between traumatic RCT and PHF. Given the similar expression pattern between traumatic RCT and PHF, they were integrated as the traumatic group. In comparison with the traumatic group, 1,983 up-regulated and 2,205 down-regulated DEGs were detected in degenerative SAB. Enrichment analysis of up-regulated DEGs uncovered an elevated inflammatory and immunologic responses in degenerative SAB. Single-cell transcriptomic analysis revealed macrophage represented the immune cell with the most DEGs between the degenerative and traumatic RCT. CONCLUSION: Our results revealed that the SAB in degenerative RCT exhibited a different transcriptional signature compared to that in traumatic RCT, and enrichment analysis showed immunologic and inflammatory activations. Macrophages may play a fundamental role in this process.

Median nerve lesions in pediatric displaced supracondylar humerus fracture: A prospective neurological, electrodiagnostic and ultrasound characterization.

BACKGROUND AND PURPOSE: Supracondylar humerus fractures (SCHFs) are the most common elbow fractures in children. Traumatic median nerve injury and isolated lesions of its pure forearm motor branch, anterior interosseus nerve (AIN), have both been independently reported as complications of displaced SCHFs. Our main objectives were to characterize the neurological syndrome to distinguish median nerve from AIN lesions and to determine the prognosis of median nerve lesions after displaced SCHFs. METHODS: Ten children were prospectively followed for an average of 11.6 months. Patients received a standardized clinical examination and high-resolution ultrasound of the median nerve every 1-3 months starting 1-2 months after trauma. Electrodiagnostic studies were performed within the first 4 months and after complete clinical recovery. RESULTS: All children shared a clinical syndrome with predominant but not exclusive affection of AIN innervated muscles. High-resolution ultrasound uniformly excluded persistent nerve entrapment and neurotmesis requiring revision surgery but visualized post-traumatic median nerve neuroma at the fracture site in all patients. Electrodiagnostic studies showed axonal motor and sensory median nerve neuropathy. All children achieved complete functional recovery under conservative management. Motor recovery required up to 11 months and differed between involved muscles. CONCLUSIONS: It was shown that neurological deficits of the median nerve in displaced SCHFs exceeded an isolated AIN lesion. Notably, detailed neurological follow-up examinations and sonographic exclusion of persistent nerve compression were able to guide conservative therapy in affected children. Under these conditions the prognosis of median nerve lesions was excellent despite severe initial deficits, development of neuroma and axonal injury.

Incidence of four major osteoporotic fragility fractures among older individuals in Sado, Japan, in 2020.

INTRODUCTION: This study compared the 2020 incidence of fragility fractures in Sado City with those from 2004 to 2015. MATERIALS AND METHODS: Data from patients aged ≥ 60 years living in Sado City with fragility fractures in the hip, vertebral, distal radius, and proximal humerus between January 1 and December 31, 2020, were collected. We examined the number and incidence of four types of osteoporotic fractures in the older population aged ≥ 60 years living in Sado City in 2020. We compared the results with those of the 2004, 2010, and 2015 surveys, examining the temporal change and trend in the incidence of the four fracture types in this population. We investigated the use rate of anti-osteoporotic medications and the relationship between their administration and the occurrence of fragility fractures. RESULTS: The age-specific incidence of hip fractures slightly decreased from 2015. However, the incidence of the other three fractures slightly increased, although the difference was not statistically significant. The incidence of hip fractures markedly increased in the 80 s. In 2020, the percentage of patients taking anti-osteoporotic agents before the occurrence of fractures decreased to 12.4% from 14.5% in 2015; it increased from 4% in 2004 to 7.6% in 2010. CONCLUSION: The 2020 incidence of the four fractures did not decrease, and the percentage of patients receiving anti-osteoporotic agents did not increase. A higher frequency of osteoporosis treatment is necessary to reduce the incidence of fragility fractures. We recommend using anti-osteoporotic agents to prevent hip fractures among individuals in their mid-70 s and above.

Durability of intercalary endoprosthesis for humeral reconstruction.

INTRODUCTION: The humerus is a common site of metastases and primary tumors. For some patients with a segmental defect and/or diaphyseal cortical destruction a cemented intercalary device may provide a more reliable construct, however data on their use is limited. METHODS: We reviewed 43 (28 male and 15 female) patients treated with an intercalary humeral spacer at a single tertiary referral center between 1989 and 2022. Humeral lesions were most commonly secondary to metastatic disease (n = 29, 68%), with 25 (58%) patients presenting with a pathologic fracture. Mean age and body mass index were 66 years and 27.9 kg/m2 . First generation taper joint device were used in 22 patients and second-generation lap device in 21 patients. RESULTS: Following reconstruction the 2-year overall survival was 30%. Mechanical complications occurred in 11 patients, most commonly aseptic loosening (n = 6, 14%). With death as a competing risk, the cumulative incidence of mechanical failure was 28% at 2-years postoperative. Following the procedure, mean Musculoskeletal Tumor Society scores was 70% and mean shoulder elevation was 87°. CONCLUSION: Reconstruction of the humeral diaphysis with an intercalary endoprosthesis provides restoration of function of the upper extremity, however, is associated with one in four patients having mechanical failure.

Ballistic long bone fracture pattern: an experimental study.

When dealing with badly preserved cadavers or skeletal human remains, the assessment of death circumstances remains challenging. When forensic evidence cannot be taken from the skin and soft tissue, the information may only be deduced from more resistant elements such as bone. Compared to cranial gunshot injuries, reliable data on ballistic long bone trauma remains scarce. This study aims to define ballistic fracture characteristics in human long bones. The shaft of 16 femurs and 13 humeri from body donors was perpendicularly shot with a 9-mm Luger full metal jacket bullet at an impact velocity of 360 m/s from a distance of 2 m. Some bones were embedded in Clear Ballistics Gel®, and some were shot without soft tissue simulant in order to better visualise the fracture propagation on the high-speed camera. The fractures were examined macroscopically and compared between the sample groups. We consistently found comminuted fractures with a stellate pattern. Fracture details were classified into entrance, exit and general characteristics. For some traits, we detected different occurrence values in the group comparison. The results indicate that some of the traits depend on bone properties such as shaft diameter, bone length and cortical thickness. The presence of ballistic gel also influenced some fracture traits, emphasising the relevance of soft tissue simulant in osseous gunshot experiments. This study revealed new insights in the detailed fracture pattern of human long bones. These may serve as guidelines for the identification and reconstruction of gunshot trauma in human long bones.

Neonatal upper limb fractures - a narrative overview of the literature.

The aim of this paper is to review the topic of neonatal fractures of the upper limb, describing the different types of fractures focusing on the etiology, epidemiology, risk factors, clinical approach, diagnosis, treatment and prognosis of these injuries. We included all types of research studies, both experimental and observational, published in English, French, Portuguese and Spanish. The information was obtained using the keywords neonatal upper limb fracture, clavicle fracture or humerus fracture from the following resources: MEDLINE database, Embase® database and LILACS database. Other resources such as hand searches of the references of retrieved literature and authoritative texts, personal and hospital libraries searching for texts on upper limb neonatal fractures, discussions with experts in the field of upper limb neonatal fractures and personal experience, were also considered for the completion of the article.Neonatal fractures of the upper limb are consensually considered to have a good prognosis and no long-term sequelae. Conservative treatment is the option in the vast majority of the fractures and is associated with excellent results, with good healing, full range of motion, adequate remodeling without obvious deformity, neurologic impairment or functional implications.

Peripheral nerve injuries associated with dislocated supracondylar fractures of distal humerus in children: incidence and need of surgical treatment.

PURPOSE: The objective of this study was to determine the incidence, necessity for neurosurgical intervention, and overall results of the treatment of pediatric peripheral nerve injuries associated with dislocated supracondylar fractures of the distal humerus. METHOD: A retrospective analysis of pediatric patients with supracondylar fractures treated from April 2019 to April 2022 with a minimum follow-up of 3 months was conducted. RESULTS: Of 453 included patients, there were 51 recorded peripheral nerve injuries. The ulnar nerve was the most frequently injured nerve. Nine patients required neurosurgical intervention, with the most common procedure being the release of entrapped nerves. The combination of a supracondylar fracture and arterial injury was identified as a significant risk factor for peripheral nerve injury (p < 0.001). Only one patient experienced an unsatisfactory outcome. CONCLUSION: Although the prognosis for peripheral nerve injuries in children with supracondylar fractures is generally favorable, these injuries must be properly identified. We recommend an active neurosurgical approach in children with persisting neurological deficits to minimize the risk of permanent neurological impairment.

Radiographic assessment of incidental bone lesions of the proximal humerus: a prevalence study.

BACKGROUND: An increased prevalence of benign lesions has been associated with the increased use of radiological tools in orthopedic practice. PURPOSE: To investigate the inter-observer reliability of the radiographic detection of lesions on the proximal humerus between different observers. MATERIAL AND METHODS: X-ray radiological examinations of 17,243 patients were performed by an orthopedic surgeon to assess the presence of proximal humeral bone lesions. After this initial screening, 201 patients with lesions were identified and these 201 scans were assessed by three different physicians: an orthopedic oncologist, an orthopedic surgeon, and a musculoskeletal radiologist. Of the 201 patients with lesions, 80 had magnetic resonance imaging in addition to X-rays and were assessed. The diagnosis of the lesions was determined by each participant according to their radiological appearance to assess inter-observer reliability. RESULTS: The prevalence of proximal humeral lesions was determined by the orthopedic surgeon to be 1.165% (201 of 17,243 patients). In 201 patients with a lesion, the mean age was 48 ± 17 years (range = 18-91 years). According to the assessments of the orthopedic oncologist, orthopedic surgeon, and musculoskeletal radiologist, the most common bone lesion identified was enostosis, with prevalence percentages of 53.7%, 59.7%, and 64.7%, respectively. A noteworthy consensus exists in the collective diagnosis of bone lesions among the three investigators, demonstrated by a substantial agreement with Fleiss' κ at 0.74 (P < 0.001). CONCLUSION: There was remarkable agreement between the three investigators on the collective diagnosis of bone lesions. Enostosis was the most common bone lesion at the proximal humerus in our series.

Health-economic evaluation of orthogeriatric co-management for patients with forearm or humerus fractures: an analysis of insurance claims data from Germany.

Orthogeriatric co-management (OGCM) describes a collaboration of orthopedic surgeons and geriatricians for the treatment of fragility fractures in geriatric patients. While its cost-effectiveness for hip fractures has been widely investigated, research focusing on fractures of the upper extremities is lacking. Thus, we conducted a health economic evaluation of treatment in OGCM hospitals for forearm and humerus fractures.In a retrospective cohort study with nationwide health insurance claims data, we selected the first inpatient stay due to a forearm or humerus fracture in 2014-2018 either treated in hospitals that were able to offer OGCM (OGCM group) or not (non-OGCM group) and applied a 1-year follow-up. We included 31,557 cases with forearm (63.1% OGCM group) and 39,093 cases with humerus fractures (63.9% OGCM group) and balanced relevant covariates using entropy balancing. We investigated costs in different health sectors, length of stay, and cost-effectiveness regarding total cost per life year or fracture-free life year gained.In both fracture cohorts, initial hospital stay, inpatient stay, and total costs were higher in OGCM than in non-OGCM hospitals. For neither cohort nor effectiveness outcome, the probability that treatment in OGCM hospitals was cost-effective exceeded 95% for a willingness-to-pay of up to €150,000.We did not find distinct benefits of treatment in OGCM hospitals. Assigning cases to study groups on hospital-level and using life years and fracture-free life years, which might not adequately reflect the manifold ways these fractures affect the patients' health, as effectiveness outcomes, might have underestimated the effectiveness of treatment in OGCM hospitals.

Application of Kirschner wire placement guided technology in paediatric supracondylar humerus fractures.

BACKGROUND: To analyze the clinical efficacy of K-wire placement guided technology in paediatric supracondylar humerus fractures. METHODS: A retrospective study was conducted in 105 patients who underwent closed reduction and percutaneous pinning surgeries in our hospital from June 2019 to August 2022. 54 patients treated with a assisted reduction fixation device to assist in closed reduction and percutaneous K-wire cross-fixation were allocated into the Non-guided group, and 51 patients with K-wire placement guided technology to guide K-wire placement were assigned into the Guided group. The operation duration, number of disposable K-wire placement, intraoperative fluoroscopy frequency, Baumann angle, carrying angle, fracture healing time and Flynn score of elbow joint function at the final follow-up were compared between two groups. The postoperative complications of two groups were recorded. RESULTS: There were significant differences between two groups in terms of operation duration, intraoperative fluoroscopy frequency, and disposable K-wire placement rate (p < 0. 05), while no significant differences of Baumann angle, carrying angle and the fracture healing time between two groups were observed (p > 0. 05). In the control group, ulnar nerve injury in 2 case, pin site infection in 4 cases, mild cubitus varus in 2 cases and loss of reduction in 4 cases were detected. In the study group, ulnar nerve injury in 1 case, pin site infection in 2 cases and loss of reduction in 1 case was observed. There was no significant difference in Flynn scores between two groups. CONCLUSION: K-wire placement guided technology is simple and convenient. The application of K-wire placement guided technology could relatively improved disposable K-wire placement rate, shorten the intraoperative fluoroscopy frequencies and reduce complication rates.

Cement-augmented locked plate fixation proximal humerus fractures in elderly patient: a systematic review and meta-analysis.

BACKGROUND: This systemic review and meta-analysis aimed to evaluate the clinical outcomes of proximal humeral fracture in elderly patient fixation using locked plate with or without cement augmentation. METHODS: The databases of PubMed, Embase, and Cochrane Library were searched in August 2023 for literature comparing the clinical outcomes of patients with PHFs treated with locked plate alone and locked plate augmented with cement. Data describing study design; level of evidence; inclusion criteria; demographic information; final follow-up; revision rate; implant failure rate; avascular necrosis rate; total complication rate; constant score; and disability of arm, shoulder, and hand (DASH) score were collected. RESULTS: Eight studies (one randomized-controlled trial and seven observational studies), involving 664 patients, were identified. Compared with locked plates alone, using cement-augmented locked plates reduced the implant failure rate (odds ratio (OR) = 0.19; 95% confidence interval (CI) 0.10-0.39; P < 0.0001) and total complication rate (OR = 0.45; 95% CI 0.29-0.69; P = 0.0002) and improved DASH scores (mean difference (MD) = 2.99; 95% CI 1.00-4.98; P = 0.003). However, there was no significant difference in clinical outcomes, including revision rate, avascular necrosis rate, and constant score. CONCLUSION: In this review and meta-analysis, fixation of the PHFs in elderly patients using locked plates with or without cement augmentation has no significant difference in revision rate, but the implant failure and total complication rates may be lesser on using the cement-augmented locked plate for fixation than on using a locked plate alone. Good results are expected for most patients treated with this technique. TRIAL REGISTRATION: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)21 guidelines were followed to conduct this systematic review and meta-analysis and was registered as a protocol in PROSPERO (CRD42022318798).

CT-based measurement and analysis of distal humerus morphology in healthy adults from Northern China.

BACKGROUND: This study aims to investigate the morphological characteristics of the distal humerus in healthy adults from northern China using computed tomography and three-dimensional reconstruction techniques and compared whether there were diferences in morphology among populations from diferent geographical regions. METHODS: The CT data of 80 patients were imported into Mimics software for three-dimensional reconstruction and measurement. The differences in distal humeral morphological parameters between different genders and sides were compared, and the correlation between the parameters was explored. The distal humeral morphological parameters between Western and Chinese populations based on current and previous pooled results were compared. RESULTS: Thirty-one morphological parameters were measured and analyzed in this study. The average (and standard deviation) of capitellum depth, capitellum width, capitellum height, distal humerus width, epitrochlea width, and humeral metaphyseal width was 10.83 ± 1.18 mm, 17.60 ± 2.06 mm, 21.10 ± 2.03 mm, 44.38 ± 4.07 mm, 12.02 ± 1.90 mm and 58.95 ± 4.86 mm, these parameters were significantly higher (P < 0.001*) in males than females. The capitellum width (r = -0.300, P = 0.007*), anterior lateral trochlear depth (r =-0.227, P = 0.043*), medial crest coronal tangential angle (r = 0.307, P = 0.006*), olecranon fossa volume (r = -0.408, P < 0.001*), olecranon fossa surface area (r = -0.345, P = 0.002*) and coronoid fossa surface area (r = -0.279, P = 0.012*) were significantly correlated with the age of the subjects. In the comparison of people from different regions, the capitellum height, lateral trochlear high, trochlear groove high, trochlear depth and medial trochlear high of the Western population were 23.25 ± 2.56 m, 21.6 ± 2.20 mm, 17.8 ± 2.00 mm, 17.80 ± 2.00 mm, 29.9 ± 4.10 mm, are significantly higher than those in the Chinese population. while capitellum width (15.55 ± 2.68 mm) and capitellum depth (9.00 ± 1.00 mm) were slightly lower. CONCLUSION: The findings provide a basis for the design of distal humeral orthopaedic implants, ensuring greater alignment with the anatomical structure of the distal humerus and improved surgical outcomes. Furthermore, the study provides a reference point for the diagnosis and classification of distal humeral diseases, as well as guidance for patient rehabilitation.

A clinical study on robot navigationassisted intramedullary nail treatment for humeral shaft fractures.

BACKGROUND: The purpose of this study was to evaluate the advantages of robot navigation system-assisted intramedullary nail treatment for humeral shaft fractures and compare it's efficacy with that of traditional surgical intramedullary nail treatment. MATERIALS AND METHODS: This was a retrospective analysis of patients with humeral shaft fractures who received intramedullary nail treatment at our centre from March 2020 to September 2022. The analysis was divided into a robot group and a traditional surgical group on the basis of whether the surgery involved a robot navigation system. We compared the baseline data (age, sex, cause of injury, fracture AO classification, and time of injury-induced surgery), intraoperative conditions (surgery time, length of main nail insertion incision, postoperative fluoroscopy frequency, intraoperative bleeding), fracture healing time, and shoulder joint function at 1 year postsurgery (ASES score and Constant-Murley score) between the two groups of patients. RESULTS: There was no statistically significant difference in the baseline data or average fracture healing time between the two groups of patients. However, the robotic group had significantly shorter surgical times, longer main nail incisions, fewer intraoperative fluoroscopies, and less intraoperative blood loss than did the traditional surgery group (P < 0.001). CONCLUSION: Robot navigation system-assisted intramedullary nail fixation for humeral shaft fractures is a reasonable and effective surgical plan. It can help surgeons determine the insertion point and proximal opening direction faster and more easily, shorten the surgical time, reduce bleeding, avoid more intraoperative fluoroscopy, and enable patients to achieve better shoulder functional outcomes.

Development of the humeral head offset index for control of humeral torsion.

BACKGROUND: Control of humeral torsion can present a challenge, especially intraoperatively during closed reduction and fixation of humeral shaft fractures or 2-part surgical neck fractures of the proximal humerus. The objective of this study is to develop and validate an indirect method for the assessment of humeral torsion using an index that is linearly correlated with rotational arm position and can be derived from only a single plain radiographic image of the proximal humerus. METHODS: The Humeral Head Offset Index (HHOI) is calculated as the ratio of the medial and lateral offset of the humeral head measured from the outer cortices of the shaft on a plain radiographic or fluoroscopic image. The relationship of HHOI with humeral torsion was first verified on a sawbone model with radiopaque characteristics under fluoroscopic control. Different degrees of retroversion were simulated through manual rotation of the humerus with a digital protractor in 5° increments until 40° internally rotated and then in 5° increments until 40° externally rotated from the neutral position. The same procedure was subsequently performed digitally on Digitally Reconstructed Radiographs (DRRs) from computed tomography (CT) dataset of the sawbone. Next, the HHOI index was applied to eight randomly selected patients with total humerus CT using the same method. Spearman's rho was calculated for the bivariate analysis of correlation between the simulated degree of retroversion and the HHOI. Strength of correlation was classified according to Koo and Li. Interrater and intrarater reliability of three blinded observers with repetition of measurement after three months were analyzed by assessing the intraclass correlation coefficient (ICC). RESULTS: Both in the sawbone model and in DRRs, we demonstrated a high to very high significant linear correlation between simulated retroversion and the HHOI. ICC values demonstrated excellent interrater reliability and excellent intrarater reliability for measurement of the HHOI. CONCLUSIONS: The HHOI is a new, simple, reliable index that has a linear relationship to the rotation of the humerus and can therefore allow an indirect control of humeral torsion in comparison to the contralateral side.

Clinical validation of artificial intelligence-based preoperative virtual reduction for Neer 3- or 4-part proximal humerus fractures.

BACKGROUND: If reduction images of fractures can be provided in advance with artificial-intelligence (AI)-based technology, it can assist with preoperative surgical planning. Recently, we developed the AI-based preoperative virtual reduction model for orthopedic trauma, which can provide an automatic segmentation and reduction of fractured fragments. The purpose of this study was to validate a quality of reduction model of Neer 3- or 4-part proximal humerus fractures established by AI-based technology. METHODS: To develop the AI-based preoperative virtual reduction model, deep learning performed the segmentation of fracture fragments, and a Monte Carlo simulation completed the virtual reduction to determine the best model. A total of 20 pre/postoperative three-dimensional computed tomography (CT) scans of proximal humerus fracture were prepared. The preoperative CT scans were employed as the input of AI-based automated reduction (AI-R) to deduce the reduction models of fracture fragments, meanwhile, the manual reduction (MR) was conducted using the same CT images. Dice similarity coefficient (DSC) and intersection over union (IoU) between the reduction model from the AI-R/MR and postoperative CT scans were evaluated. Working times were compared between the two groups. Clinical validity agreement (CVA) and reduction quality score (RQS) were investigated for clinical validation outcomes by 20 orthopedic surgeons. RESULTS: The mean DSC and IoU were better when using AI-R that when using MR (0.78 ± 0.13 vs. 0.69 ± 0.16, p < 0.001 and 0.65 ± 0.16 vs. 0.55 ± 0.18, p < 0.001, respectively). The working time of AI-R was, on average, 1.41% of that of MR. The mean CVA of all cases was 81%±14.7% (AI-R, 82.25%±14.27%; MR, 76.75%±14.17%, p = 0.06). The mean RQS was significantly higher when AI-R compared with MR was used (91.47 ± 1.12 vs. 89.30 ± 1.62, p = 0.045). CONCLUSION: The AI-based preoperative virtual reduction model showed good performance in the reduction model in proximal humerus fractures with faster working times. Beyond diagnosis, classification, and outcome prediction, the AI-based technology can change the paradigm of preoperative surgical planning in orthopedic surgery. LEVEL OF EVIDENCE: Level IV.

Clinical and radiographic results of locking plate with medial support screw in Proximal Humerus fracture - the more, the better?

BACKGROUND: The calcar of the proximal humerus is a fundamental structure for medial humeral column support. This study aimed to assess the outcome of osteosynthesis across cases of unstable proximal humerus fractures (PHFs) with medial calcar comminution, following treatment with a PHILOS locking plate and medial support screw (MSS). METHODS: Between January 2010 and December 2018, we retrospectively analyzed the outcomes of 121 cases of osteosynthesis for PHFs with medial column disruption. For the medial support, at least one oblique screw was inserted within 5 mm of the subchondral bone in the inferomedial quadrant of the humeral head. All patients were categorized into two groups: 26 patients in the single MSS group, and 95 in the multiple MSS group. Follow-up after at least an year involved clinical and radiographic outcome evaluations, and correspondingly measuring the Constant-Murley score, University of California, Los Angeles (UCLA) shoulder scale, pain visual analogue scale (VAS), major complications, neck-shaft angle (NSA), humeral head height (HHH), and the eventual time to bone union. Risk factors for the major complications were assessed by multivariate logistic regression analyses. RESULTS: The cohort's mean age was 64.4 ± 15.4 years, and the mean follow-up duration was 19.5 ± 7.6 months. At the final follow-up, between the single MSS and multiple MSS groups, no significant differences in the Constant-Murley score (p = 0.367), UCLA score (p = 0.558), VAS (p = 0.571), time to bone union (p = 0.621), NSA loss (p = 0.424), and HHH loss (p = 0.364) were observed. The incidence of complications (p = 0.446) based on the number of MSS were not significantly different. The initial insufficient reduction after surgery (of NSA < 125°) was found to be a significant risk factor for post-surgical complications. CONCLUSIONS: To treat unstable PHFs, the use of at least one MSS along with a locking plate system is sufficient to achieve satisfactory outcomes. Successful operative treatment using a locking plate for PHF treatment is inherent in anatomical fracture reduction, coupled with medial column support.

Transitivity, coherence, and reliability of network meta-analyses comparing proximal humerus fracture treatments: a meta-epidemiological study.

BACKGROUND: Network meta-analyses can be valuable for decision-makers in guiding clinical practice. However, for network meta-analysis results to be reliable, the assumptions of both transitivity and coherence must be met, and the methodology should adhere to current best practices. We aimed to assess whether network meta-analyses of randomized controlled trials (RCTs) comparing interventions for proximal humerus fractures provide reliable estimates of intervention effects. METHODS: We searched PubMed, EMBASE, The Cochrane Library, and Web of Science for network meta-analyses comparing interventions for proximal humerus fractures. We critically assessed the methodology regarding the development of a protocol, search strategy, trial inclusion, outcome extraction, and the methods used to conduct the network meta-analyses. We assessed the transitivity and coherence of the network graphs for the Constant score (CS), Disabilities of the Arm, Shoulder, and Hand score (DASH), and additional surgery. Transitivity was assessed by comparing probable effect modifiers (age, gender, fracture morphology, and comorbidities) across intervention comparisons. Coherence was assessed using Separating Indirect from Direct Evidence (SIDE) (Separating Indirect from Direct Evidence) and the design-by-treatment interaction test. We used CINeMA (Confidence in Network Meta-analyses) to assess the confidence in the results. RESULTS: None of the three included network meta-analyses had a publicly available protocol or data-analysis plan, and they all had methodological flaws that could threaten the validity of their results. Although we did not detect incoherence for most comparisons, the transitivity assumption was violated for CS, DASH, and additional surgery in all three network meta-analyses. Additionally, the confidence in the results was 'very low' primarily due to within-study bias, reporting bias, intransitivity, imprecision, and heterogeneity. CONCLUSIONS: Current network meta-analyses of RCTs comparing interventions for proximal humerus fractures do not provide reliable estimates of intervention effects. We advise caution in using these network meta-analyses to guide clinical practice. To improve the utility of network meta-analyses to guide clinical practice, journal editors should require that network meta-analyses are done according to a predefined analysis plan in a publicly available protocol and that both coherence and transitivity have been adequately assessed and reported.

Comparative efficacy and safety of medical treatments for proximal humerus fractures: a systematic review and network meta-analysis.

BACKGROUND: Various surgical techniques and conservative therapies are useful tools for treating proximal humerus fractures (PHFs), but it is important to understand how to properly utilize them. Therefore, we performed a systematic review and network meta-analysis to compare and rank the efficacy and safety of medical treatments for PHF. METHODS: PubMed, Embase, the Cochrane Library, and the ClinicalTrials.gov databases were systematically searched for eligible randomized controlled trials (RCTs) from inception until June 2022. Conservative therapy-controlled or head-to-head RCTs of open reduction internal fixation (ORIF), intramedullary nailing (IMN), hemiarthroplasty (HA), and reverse total shoulder arthroplasty (RTSA) used for the treatment of adult patients with PHF were included. The surface under the cumulative ranking (SUCRA) probabilities were applied to compare and rank the effects of medical treatments for PHF. RESULTS: Eighteen RCTs involving 1,182 patients with PHF were selected for the final analysis. Mostly baseline characteristics among groups were well balanced, and the imbalanced factors only included age, injury type, medial comminution, blood loss, and cognitive function in single trial. The SUCRA probabilities found that RTSA provided the best effect on the Constant-Murley score (SUCRA: 100.0%), and the disabilities of the arm, shoulder and hand (DASH) score (SUCRA: 99.0%). Moreover, HA (SUCRA: 85.5%) and RTSA (SUCRA: 68.0%) had a relatively better effect on health-related quality of life than the other treatment modalities. Furthermore, conservative therapy (SUCRA: 84.3%) and RTSA (SUCRA: 80.7%) were associated with a lower risk of secondary surgery. Finally, the best effects on the risk of complications are varied, including infection was observed with conservative therapy (SUCRA: 94.2%); avascular necrosis was observed in HA (SUCRA: 78.1%), nonunion was observed in RTSA (SUCRA: 69.6%), and osteoarthritis was observed in HA (SUCRA: 93.9%). CONCLUSIONS: This study found that RTSA was associated with better functional outcomes, while the comparative outcomes of secondary surgery and complications varied. Optimal treatment for PHF should consider patient-specific factors.

3D printing assisted MIPO for treatment of complex middle-proximal humeral shaft fractures.

BACKGROUND: This study was designed to explore the clinical efficacy of 3-dimensional (3D) printing assisted minimally invasive percutaneous plate osteosynthesis (MIPO) technique by comparing the clinical outcomes with traditional open reduction and internal plating fixation (ORIF) for treating complex middle-proximal humerus fractures (AO 12C fracture type). MATERIALS AND METHODS: The data of 42 participants who received a complicated middle-proximal humerus fracture from the beginning of 2018 to the end of 2022 were retrospectively analyzed. All patients were assigned to two groups: MIPO with detailed preoperative planning assisted by 3D printing technique (MIPO group), and traditional ORIF (ORIF group). RESULTS: This study included 21 patients in the ORIF group and 21 patients in the MIPO group. All patients were followed-up for at least one year (mean: 16.12 ± 4.13 months), and no difference was observed in the range of shoulder joint motion (ROM), Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) scores and Constant scores between the two groups. However, the occurrence of complications (surgical incision site infection, implant loosening, bone nonunion and radial nerve palsy) in ORIF group was remarkably higher compared to the MIPO group. All the cases achieved bone union within the MIPO group. Significant differences were found in surgical time, intraoperative blood loss and fracture healing time between the two groups. CONCLUSION: Preoperative 3D printing assisted MIPO technique exhibits obvious advantages in high operational efficiency and low occurrence of complications, which is worthy of clinical application for treating complex middle-proximal humeral shaft fractures.