AI-assisted Analysis to Facilitate Detection of Humeral Lesions on Chest Radiographs.

Purpose To develop an artificial intelligence (AI) system for humeral tumor detection on chest radiographs (CRs) and evaluate the impact on reader performance. Materials and Methods In this retrospective study, 14 709 CRs (January 2000 to December 2021) were collected from 13 468 patients, including CT-proven normal (n = 13 116) and humeral tumor (n = 1593) cases. The data were divided into training and test groups. A novel training method called false-positive activation area reduction (FPAR) was introduced to enhance the diagnostic performance by focusing on the humeral region. The AI program and 10 radiologists were assessed using holdout test set 1, wherein the radiologists were tested twice (with and without AI test results). The performance of the AI system was evaluated using holdout test set 2, comprising 10 497 normal images. Receiver operating characteristic analyses were conducted for evaluating model performance. Results FPAR application in the AI program improved its performance compared with a conventional model based on the area under the receiver operating characteristic curve (0.87 vs 0.82, P = .04). The proposed AI system also demonstrated improved tumor localization accuracy (80% vs 57%, P < .001). In holdout test set 2, the proposed AI system exhibited a false-positive rate of 2%. AI assistance improved the radiologists' sensitivity, specificity, and accuracy by 8.9%, 1.2%, and 3.5%, respectively (P < .05 for all). Conclusion The proposed AI tool incorporating FPAR improved humeral tumor detection on CRs and reduced false-positive results in tumor visualization. It may serve as a supportive diagnostic tool to alert radiologists about humeral abnormalities. Keywords: Artificial Intelligence, Conventional Radiography, Humerus, Machine Learning, Shoulder, Tumor Supplemental material is available for this article. © RSNA, 2024.

The Gartland classification for expediting supracondylar humerus fracture triage: a collaborative approach to structured reporting between pediatric radiologists and orthopedists.

BACKGROUND: The modified Gartland classification is an important tool for evaluation of pediatric supracondylar humerus fractures (SCHF) because it can direct treatment decisions. Gartland type I can be managed outpatient, while emergent surgical consult occurs with type II and III. This study assesses the interobserver reliability of the Gartland classification between pediatric radiologists and orthopedic providers. METHODS: A retrospective review of 320 children diagnosed with a SCHF at a single tertiary children's hospital during 2022 was conducted. The Gartland classification documented in the radiographic report by a pediatric radiologist and the classification documented in the first encounter with an orthopedic provider was collected. Kappa value was used to assess interobserver reliability of classifications between radiologists and orthopedic providers. A second group of 76 Gartland type I SCHF from 2015, prior to our institution's implementation of structured reporting, was reviewed for comparison of unnecessary orthopedic consults at initial presentation. RESULTS: The Gartland classification has excellent interobserver reliability between radiologists and orthopedic providers with 90 % (289/320) agreement and kappa of 0.854 (confidence interval: 0.805-0.903). The most frequent disagreement that occurred was fractures classified as type II by radiology and type III by orthopedics. There were similar rates of consults for the 2015 and 2022 cohorts (p = 0.26). CONCLUSION: The Gartland classification system is a reliable and effective tool for communication between radiologists and orthopedic providers. Implementing a structured reporting system has the potential to improve triage efficiency for SCHF.

Bone deformity in sports-related elbow osteoarthritis: influence of osteochondritis dissecans of the capitellum-a cross-sectional study.

INTRODUCTION: Sports activity can cause elbow osteoarthritis, which subsequently induces bone deformity. Osteochondritis dissecans (OCD) of the capitellum develops defects of articular surfaces and can exacerbate bone deformity. This study aimed to investigate whether OCD exacerbates deformities in sports-related elbow osteoarthritis. MATERIALS AND METHODS: Twenty-one patients who underwent bilateral computed tomography preoperatively followed by surgery for sports-related elbow osteoarthritis were included. Patients were divided into two groups according to the presence or absence of an OCD history: OCD + (n = 6) and OCD- (n = 15). Bilateral three-dimensional bone models of the humerus, ulna, and radius were created using computed tomography data, and bone deformities were extracted by subtracting healthy mirror models from the affected models using a Boolean operation. Bone deformities were divided into 22 regions in the 3 bones. The volume of the deformity was estimated by correlating the anteroposterior and lateral diameters of the OCD and by comparing the two groups. RESULTS: The anteroposterior diameter of the OCD correlated with the articular surface of the medial trochlear notch, whereas the lateral diameter correlated with the whole ulna, medial gutter of the ulna, whole radius, and lateral side of the radial head. The deformities were 2.2 times larger in the whole humerus, 1.9 times larger in the whole ulna, and 3.0 times larger in the whole radius in the OCD + group than in the OCD- group. The deformities were significantly larger in the OCD + group than in the OCD- group in the radial fossa, posterior capitellum, medial gutter, and lateral gutter in the humerus, medial gutter in the ulna, and lateral, anterior, and posterior sides of the radial head. CONCLUSION: Larger OCD exacerbated deformity in elbow OA, and the presence of OCD exacerbated deformities in sports-related elbow OA. These results demonstrate the highlight of preventing OCD progression.

Poor clinical outcomes and high rates of dislocation after modular reverse shoulder arthroplasty for proximal humeral oncologic resection.

PURPOSE: The shoulder is the most common site for upper extremity tumors. The aim of the study was to analyze the outcomes and the complications of modular reverse shoulder arthroplasty (RSA) after proximal humerus resection. METHODS: We retrospectively included 15 consecutive patients who underwent a modular MUTARS™ RSA reconstruction after proximal humerus tumour resection between 2017 and 2020. The mean age was 52 years. Their clinical outcomes were assessed using the Constant-Murley score and the MSTS shoulder. Radiological outcomes were assessed based on the presence of loosening, osteolysis, and scapular notching. Complications such as dislocation, oncological recurrence, and infection were assessed. Mean follow-up time was 32.9 months (24 to 45). RESULTS: The mean adjusted Constant score was 50.7% (min 22, max 81), and the mean MSTS score was 15.6 (min 4, max 26). We had no loosening, osteolysis, or scapular notching on the radiographs at last follow-up. We had a high complication rate of 53%: one infection, one oncological recurrence, and six dislocations (40%), of which five were re-operated. CONCLUSION: In our experience, the MUTARS™ Implantcast™ modular RSA has poor functional results and a high rate of dislocation in the case of large proximal humerus resections below the distal insertion of the deltoid.

Complete resorption of the humerus in metastatic thyroid carcinoma: a case report.

BACKGROUND: Thyroid carcinoma is the most common endocrinological malignancy, but its spread to bone is rare. Particularly, bone metastases leading to complete resorption of the humerus are extremely uncommon. We aimed to explore factors affecting treatment decision in humeral metastasis by presenting a case and analyze the possible treatments via conducting a literature review. CASE PRESENTATION: We described a case of a 68-year-old woman experiencing chronic pain in her right upper arm for six years. Clinical, radiological, and pathological evaluations confirmed humeral metastasis from thyroid carcinoma. Surgical treatments like tumor removal or limb amputation were suggested for prolonging life and pain relief, but the patient refused them and pursued conservative managements such as herbal medicine, radioactive iodine (131I) therapy, and Levothyroxine Sodium(L-T4). The humeral destruction aggravated gradually, ultimately leading to complete resorption of her right humerus. The patient could not move her right shoulder, but her forearm motion was almost normal; thus, she could complete most of her daily living activities independently. Surgical treatments such as limb amputation were advised but she still refused them for preservation of the residual limb function and preferred conservative managements. CONCLUSION: A personalized multidisciplinary approach is important for patients with bone metastasis. The balance between limb amputation for life-prolonging and pain relief and limb salvage for preservation of residual function and social and psychological well-being should be considered. Our literature review revealed that some novel surgical treatments and techniques are available for bone metastases. This case adds to our current understanding of bone metastases and will contribute to future research and treatments.

[Rare Compression Syndrome of the Median Nerve due to a Supracondylar Humeral Process and a Ligament of Struthers]. / Seltenes Kompressionssyndrom des N. medianus durch den Processus supracondylaris und das Struthers-Ligament.

INTRODUCTION: A supracondylar process is a bony spur on the distal anteromedial surface of the humerus, and it is considered an anatomical variant with a prevalence of 0.4-2.7% according to anatomical studies. In almost all cases, it is associated with a fibrous, sometimes ossified ligament, which extends from the supracondylar process to the medial epicondyle. This ligament is known in the literature as the ligament of Struthers, named after the Scottish anatomist who first described it in detail in 1854. In rare cases, the supracondylar process can be a clinically relevant finding as a cause of nerve compression syndrome. The median and ulnar nerve can be trapped by the ring-shaped structure formed by the ligament of Struthers and the supracondylar process. CASE REPORT: A 59-year-old patient with symptoms of a cubital tunnel syndrome and additional ipsilateral sensory deficits in his thumb was referred to our clinic. Electroneurography showed no signs of an additional carpal tunnel syndrome. Preoperative x-ray and CT scans of the upper arm revealed a supracondylar process, which led us to suspect an associated entrapment of the median nerve. An MRI scan of the upper arm showed a ligament of Struthers and signs of a related median nerve compression as we initially assumed. We performed a surgical decompression of the median nerve in the distal upper arm and of the ulnar nerve in the cubital tunnel. Intraoperatively, there was evidence of compression of the median nerve due to the supracondylar process and the ligament of Struthers. The latter was cleaved and then resected along with the supracondylar process. Three months after surgery, the patient had no motor or sensory deficits. SUMMARY: The ring-shaped structure formed by the supracondylar process and ligament of Struthers represents a rare cause of compression syndrome of the median and ulnar nerve. Its incidence remains unknown so far. This anatomical variant should be considered a differential diagnosis in case of possibly related nerve entrapment symptoms after ruling out other, more frequent nerve compression causes. Moreover, the supracondylar process should be completely resected including the periosteum during surgery to minimise the risk of recurrence.

18 F-FDG PET/CT Imaging of Isolated Myeloid Sarcoma in the Right Humerus.

ABSTRACT: Myeloid sarcoma is a neoplastic mass formed by the infiltration of primitive or immature myeloid cells into organs and tissues outside the bone marrow. It may occur before, at the same time, or manifest as the recurrence of acute myeloid leukemia, myelodysplastic syndromes, and chronic myeloproliferative syndromes. It may involve any organ or tissue, including skin, soft tissue, lymph nodes, and gastrointestinal tract and bone. Isolated humerus involvement is extremely rare. Herein, we present the FDG PET/CT findings of a rare case of isolate myeloid sarcoma in the right humerus, which showed only increased bone density with moderate FDG uptake.

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.

Does A Single Osteotomy Technique for Frozen Autograft (Pedicled Freezing) in Patients With Malignant Bone Tumors of the Long Bones Achieve Union and Local Tumor Control?

BACKGROUND: Biological reconstruction by replanting the resected tumor-bearing segment is preferred by some surgeons when caring for a patient with a bone sarcoma. Frozen autografts are advantageous because they are cost-effective, provide an excellent fit, permit the maintenance of osteoinductive and osteoconductive properties, and are not associated with transmission of viral disease. The pedicle frozen autograft technique, in which only one osteotomy is made for the freezing procedure, keeping the affected segment in continuity with the host bone and soft tissue instead of two osteotomies, maintains the affected segment with the host bone and soft tissue. This could restore blood flow more rapidly in a frozen autograft than in a free-frozen autograft with two osteotomies. QUESTIONS/PURPOSES: (1) In what proportion of patients was union achieved by 6 months using this technique of frozen autografting? (2) What complications were observed in a small series using this approach? (3) What was the function of these patients as determined by Musculoskeletal Tumor Society (MSTS) score? (4) What proportion of patients experienced local recurrence? METHODS: Between 2014 and 2017, we treated 87 patients for primary sarcomas of the femur, tibia, or humerus. Of those, we considered patients who could undergo intercalary resection and showed a good response to neoadjuvant chemotherapy as potentially eligible for this technique. Based on these criteria, 49% (43 patients) were eligible; a further 9% (eight) were excluded because of inadequate bone quality (defined as cortical thickness less than 50% by CT assessment). We retrospectively studied 32 patients who were treated with a single metaphyseal osteotomy, the so-called pedicle freezing technique, which uses liquid nitrogen. There were 20 men and 12 women. The median age was 18 years (range 13 to 48 years). The median follow-up duration was 55 months (range 48 to 63 months). Patients were assessed clinically and radiologically regarding union (defined in this study as bony bridging of three of four cortices by 6 months), the proportion of patients experiencing local recurrence, the occurrence of nononcologic complications, and MSTS scores. RESULTS: Three percent (one of 32) of the patients had nonunion (no union by 9 months). The median MSTS score was 90%, with no evidence of metastases at the final follow-up interval. Nine percent (three of 32) of our patients died. The local recurrence rate was 3.1% (one of 32 patients). The mean restricted disease-free survival time at 60 months (5 years) was 58 months (95% CI 55 to 62 months). Twenty-five percent of patients (eight of 32) experienced nononcologic complications. This included superficial skin burns (two patients), superficial wound infection (two patients), deep venous thrombosis (one patient), transient nerve palsy (two patients), and permanent nerve palsy (one patient). CONCLUSION: This treatment was reasonably successful in patients with sarcomas of the femur, tibia, and humerus who could undergo an intercalary resection, and this treatment did not involve the epiphysis and upper metaphysis. It avoids a second osteotomy site as in prior reports of freezing techniques, and union was achieved in all but one patient. There were few complications or local recurrences, and the patients' function was shown to be good. This technique cannot be used in all long-bone sarcomas, but we believe this is a reasonable alternative treatment for patients who show a good response to neoadjuvant chemotherapy, those in whom intercalary resection is feasible while retaining at least 2 cm of the subchondral area, and in those who have adequate bone stock to withstand the freezing process. Experienced surgeons who are well trained on the recycling technique in specialized centers are crucial to perform the technique. Further study is necessary to see how this technique compares with other reconstruction options. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Lateral minimally invasive plate osteosynthesis (MIPO) with long PHILOS for proximal metaphyseal-diaphyseal humeral fracture: surgical techniques and a clinical series.

The minimally invasive plate osteosynthesis (MIPO) for proximal metaphyseal-diaphyseal humeral fracture is an effective alternative treatment with satisfactory outcomes. In this study, we described the surgical techniques and clinical results using MIPO via a lateral approach and long PHILOS plate fixation in 23 patients. All fractures were successfully united within a mean union time of 13.5 weeks (range 9-18). There was no iatrogenic radial nerve palsy. The deltoid power was grade 5 in all patients, except for 2 patients who had associated brachial plexus injury and gunshot injury at the deltoid muscle. The mean Constant-Murley score was 85.6 (range 16-98) and DASH score was 12.1 (range 1.7-85). Based on these findings, the lateral MIPO with long PHILOS plate fixation could be an alternative for the proximal metaphyseal-diaphyseal fractures of the humeral shaft.

Intercalary Prosthetic Reconstruction with Three-Dimensional-Printed Custom-Made Porous Component for Defects of Long Bones with Short Residual Bone Segments After Tumor Resection.

BACKGROUND: Intercalary reconstruction for patients with short residual bone segments remains challenging. Three-dimensional (3D)-printed custom-made porous implants are a promising technique for short-segment fixation in these patients. This study aims to evaluate the efficiency of 3D-printed custom-made porous components (3DCPCs) for short-segment fixation, focusing on prosthesis survivorship, radiographic results, and potential complications. METHODS: This retrospective study involved 39 patients who underwent intercalary prosthetic reconstruction with 3DCPCs after tumor resection of the femur, tibia, or humerus from June 2015 to October 2020. Segment bone loss involved the femur (n = 15), tibia (n = 16), and humerus (n = 8), leaving 78 residual bone segments. There were 46 short segments requiring 46 3DCPCs and 32 segments with the ability to accommodate 32 off-the-shelf standard uncemented stems for prosthesis fixation. Clinical and functional outcomes were evaluated. Prosthesis-overall survivorship and prosthesis-specific survivorship were analyzed using Kaplan-Meier survival analysis. Radiographic results and modes of failure of using this technique were also examined. RESULTS: The mean follow-up was 41 months. The prosthesis-overall survivorship was 87.2% and 84.6% at 2 and 5 years, respectively. The prosthesis-specific survivorship was 92.1% and 89.5% at 2 and 5 years, respectively. There was not a substantial difference in prosthesis survivorship among the femur, tibia, and humerus. The average MSTS score was 26.2, ranging from 22 to 28. The radiographic evaluation results revealed excellent or good interface (38/46) in most of the 46 porous components. A total of 38 of 46 bone segments' remolding demonstrated no change. In total, seven patients (16.3%) had complications requiring further surgery. CONCLUSION: The prosthesis survivorship of using 3DCPCs for short-segment fixation is similar or better compared to other studies involving intercalary prosthetic reconstruction with short-segment fixation. Radiographic evaluation revealed good osteointegration and avoidance of stress shielding. Overall, intercalary prosthetic reconstruction with 3DCPC is a feasible modality for patients with short residual bone segments after tumor resection.

Impact of humeral stem length on calcar resorption in anatomic total shoulder arthroplasty.

BACKGROUND: Use of standard-length anatomic total shoulder (TSA) humeral stems has been associated with high rates of medial calcar bone loss. Calcar bone loss has been attributed to stress shielding, debris-induced osteolysis, and undiagnosed infection. Short stem and canal-sparing humeral components may provide more optimal stress distribution and thus lower rates of calcar bone loss related to stress shielding. The purpose of this study is to determine whether implant length will affect the rate and severity of medial calcar resorption. METHODS: A retrospective review was performed on TSA patients treated with three different-length humeral implants (canal-sparing, short, and standard-length designs). Patients were matched 1:1:1 based on both gender and age (±4 years), resulting in 40 patients per cohort. Radiographic changes in medial calcar bone were evaluated and graded on a 4-point scale, from the initial postoperative radiographs to those at 3 months, 6 months, and 12 months. RESULTS: The presence of any degree of medial calcar resorption demonstrated an overall rate of 73.3% at one year. At 3 months, calcar resorption was observed in 20% of the canal-sparing cohort, while the short and standard designs demonstrated resorption in 55% and 52.5%, respectively (P = .002). At 12 months, calcar resorption was seen in 65% of the canal-sparing design, while both the short and standard designs had a 77.5% rate of resorption (P = .345). The severity of calcar resorption for the canal-sparing cohort was significantly lower at all time points when compared to the short stem (3 months, P = .004; 6 months, P = .003; 12 months, P = .004) and at 3 months when compared to the standard-length stem (P = .009). CONCLUSION: Patients treated with canal-sparing TSA humeral components have significantly lower rates of early calcar resorption with less severe bone loss when compared to patients treated using short and standard-length designs.

Combined Lateral Closing and Medial Opening-Wedge Proximal Humerus Osteotomy in an Adolescent with Extreme Varus Deformity: A Case Report.

CASE: This report describes the case of an athletic 12-year-old boy who presented with a 64° left proximal humeral varus angulation deformity and physeal bar secondary to multiple operations for a proximal humeral metaphyseal cystic lesion and pathologic fracture. Using a combined lateral closing and medial opening-wedge osteotomy, a 68° valgus correction was achieved with excellent clinical and functional outcomes at 16-month follow-up. Forward flexion increased from 120 to 170° preoperatively to postoperatively while abduction improved from 110° preoperatively to 170° postoperatively. CONCLUSION: A combined lateral closing and medial opening-wedge osteotomy of the proximal humerus can successfully treat cases of extreme proximal humerus varus in the growing shoulder where unilateral or dome osteotomies are not suitable.

Incidence of secondary displacement after osteosynthesis of proximal humerus fractures: a retrospective study of 185 cases.

Proximal humerus fractures are the third most common fracture in patients over 65 years of age. There is no clear consensus regarding their treatment. The objective of this retrospective observational study was to calculate the incidence of secondary displacement after osteosynthesis of these fractures and to identify possible risk factors. 185 cases were reviewed and all osteosynthesized fractures between January 2008 and December 2016 were included. Data collected included age, sex, body mass index, alcohol and tobacco use, bone mineral density of the proximal humerus, fracture type, initial displacement, management time, type of treatment, surgeon's experience and expertise, and postoperative reduction quality. A radiographic follow-up was done at least 3 months following the fracture (until consolidation). The definition of secondary displacement was: varus/valgus displacement >10°, tuberosity translation >5 mm, articular effraction or material breakage. 53 secondary displacements were found, with an incidence of 28.6%. Seventy-two percent were diagnosed at the first follow-up visit, which occurred at an average of 29 days postoperatively. Among all factors studied, only two were statistically significant for secondary displacement: 1) low proximal humeral bone density (defined by a Tingart index <4) appears to be a risk factor, with a calculated relative risk of 2.71 (p = 0.04); and 2) the operator's specialization in the upper limb appears to be a protective factor, with a relative risk of 0.27 (p = 0.01). A similar high incidence of complications after osteosynthesis of the proximal humerus is found in the literature, confirming the difficulty in managing these fractures. More attention should be given to patients with low bone density.

Anatomy of the sternum and humerus in the domestic chicken (Gallus domesticus).

Injuries of the sternum and humerus are an important welfare concern in domestic chickens (Gallus domesticus), especially laying hens. Published anatomic references using standardized terminology from the Nomina Anatomica Avium (NAA) are lacking. Objectives of the current retrospective, descriptive study were to provide a user-friendly hierarchical table of NAA-compliant anatomic terms and labeled images illustrating anatomic structures for the sternum and humerus of domestic chickens. Three-dimensional model images were downloaded from a publicly accessible platform, labeled in consultation with a veterinary anatomist, and enhanced by a medical illustrator. Findings can serve as a resource for future clinical and research applications.

Comparative bone healing with induced membrane technique (IMT) versus empty defects in septic and aseptic conditions in a novel rabbit humerus model.

BACKGROUND: Long bone defects resulting from primary trauma or secondary to debridement of fracture-related infection (FRI) remain a major clinical challenge. One approach often used is the induced membrane technique (IMT). The effectiveness of the IMT in infected versus non-infected settings remains to be definitively established. In this study we present a new rabbit humerus model and compare the IMT approach between animals with prior infection and non-infected equivalents. METHODS: A 5 mm defect was created in the humerus of New Zealand White rabbits (n = 53) and fixed with a 2.5 mm stainless steel plate. In the non-infected groups, the defect was either left empty (n = 6) or treated using the IMT procedure (PMMA spacer for 3 weeks, n = 6). Additionally, both approaches were applied in animals that were inoculated with Staphylococcus aureus 4 weeks prior to defect creation (n = 5 and n = 6, respectively). At the first and second revision surgeries, infected and necrotic tissues were debrided and processed for bacteriological quantification. In the IMT groups, the PMMA spacer was removed 3 weeks post implantation and replaced with a beta-tricalcium phosphate scaffold and bone healing observed for a further 10 weeks. Infected groups also received systemic antibiotic therapy. The differences in bone healing between the groups were evaluated radiographically using a modification of the radiographic union score for tibial fractures (RUST) and by semiquantitative histopathology on Giemsa-Eosin-stained sections. RESULTS: The presence of S. aureus infection at revision surgery was required for inclusion to the second stage. At the second revision surgery all collected samples were culture negative confirming successful treatment. In the empty defect group, bone healing was increased in the previously infected animals compared with non-infected controls as revealed by radiography with significantly higher RUST values at 6 weeks (p = 0.0281) and at the end of the study (p = 0.0411) and by histopathology with increased cortical bridging (80% and 100% in cis and trans cortical bridging in infected animals compared to 17% and 67% in the non-infected animals). With the IMT approach, both infected and non-infected animals had positive healing assessments. CONCLUSION: We successfully developed an in vivo model of bone defect healing with IMT with and without infection. Bone defects can heal after an infection with even better outcomes compared to the non-infected setting, although in both cases, the IMT achieved better healing.

Interrater reliability of subacromial ultrasound measures in the hands of novice sonographers.

INTRODUCTION: Ultrasound measures of subacromial structures are reliable in the hands of experienced sonographers, but it remains unknown if inexperienced clinicians can achieve a satisfactory level of interrater reliability. The aim was to investigate if standardised subacromial ultrasound measures are reliable in the hands of novice sonographers. METHODS: Two novice sonographers performed standardised ultrasound measures on patients diagnosed with subacromial pain syndrome and asymptomatic shoulders. The measures were: supraspinatus tendon thickness (SUPRA), subacromial bursa thickness (SASD), acromio-humeral distance (AHD) and dynamic impingement (DI). Reliability and agreement were evaluated by intraclass correlation coefficient (ICC (2.1)), standard error of measurement, minimal detectable change, 95% limits of agreement, Bland-Altman plots and Cohen's unweighted κ. RESULTS: Twenty-eight patients were recruited (28 symptomatic and 20 asymptomatic shoulders). The ICC of SUPRA ranged from 0.73 to 0.77. The ICC of SASD ranged from 0.41 to 0.88 and AHD from 0.68 to 0.72. Cohen's κ of DI in symptomatic shoulders was 0.29. CONCLUSION: The interrater reliability of novice sonographers was found to be moderate to good when assessing SUPRA and AHD. For SASD and DI, the reliability ranged from poor to good. No significant differences in SUPRA and SASD thickness were found between symptomatic and asymptomatic shoulders. FUNDING: None. TRIAL REGISTRATION: Not relevant.

Can the reduction quality of distal humeral transphyseal fractures be determined using reference measurements on conventional radiography?

OBJECTIVE: Our objective was to compare the radiological outcomes of transphyseal fractures treated using closed reduction and percutaneous fixation, without arthrography, with those of supracondylar humerus fractures treated using the same method within a similar age group. Additionally, we aimed to assess the efficacy of the reference points in the lateral and anteroposterior radiographs utilized for the evaluation of reduction. PATIENTS AND METHODS: The study included patients aged 0-3 years who underwent surgery for supracondylar and transphyseal fractures between 2013 and 2022. All the patients were diagnosed using anteroposterior (AP) and lateral elbow X-rays. No arthrographic intervention was used either in the diagnosis or treatment phase. On the AP X-rays, we assessed the alignment between the humeral shaft line and the ulnar long axis line to determine the positioning of the distal humeral physis segment in relation to the humerus. Additionally, we evaluated the relationship between the anterior cortex line of the humerus and the coronoid process on lateral radiographs. At the final follow-up visit, Flynn criteria were used for functional assessment. RESULTS: The study comprised 24 patients with supracondylar humerus fractures and 24 patients with transphyseal fractures. In the early post-operative radiographs, the humero-ulnar angle measured 6.43° (-7° - 16.6°) in the supracondylar group and 9.8° (-4.3° - 25.3°) in the transphyseal group (p = 0.087). The distance between the coronoid and the anterior humeral line was 9.19 mm (4.27 - 16.08) for the supracondylar fracture group and 8.05 mm (3.29 - 14.85) for the transphyseal fracture group (p = 0.513). CONCLUSIONS: The current study's findings suggest that both the humero-ulnar angle and the distance between the coronoid and the anterior humeral line are valuable indicators for assessing the quality of reduction in transphyseal distal humerus fractures.

Brachial Plexus Birth Injury due to Proximal Humeral Physeal Separation: A Case Report.

CASE: A 9-day-old male neonate presented with swelling over his left shoulder and reduced movements of the left upper extremity since birth. Radiographs raised a suspicion of a shoulder dislocation. Ultrasonography confirmed the diagnosis of proximal humeral physeal separation. Magnetic resonance imaging (MRI) revealed edema of the infraclavicular part of the brachial plexus. Conservative management was followed, and the injury remodeled completely at 2 years. CONCLUSION: Neonatal proximal humeral physeal separation poses a diagnostic challenge. Ultrasonography is helpful for diagnosis. MRI is indicated when concurrent brachial plexus birth injury is suspected. Conservative management yields good outcome in the absence of entrapped nerves and tendons.

Mask Region-Based Convolutional Neural Network segmentation of the humerus and scapula from proton density-weighted axial shoulder magnetic resonance images.

OBJECTIVES: This study aimed to evaluate the effectiveness of Mask Region-Based Convolutional Neural Network (R-CNN) in humerus and scapula segmentation. PATIENTS AND METHODS: The study included 665 axial proton density (PD)-weighted magnetic resonance images of 665 consecutive shoulder instability patients (412 males, 253 females; mean age: 27±5.2 years; range, 18 to 42 years) between January 2011 and December 2014. Mask R-CNN was used to automatically segment humerus and scapula regions simultaneously. Segmentation success of Mask R-CNN was compared to the manual segmentation results of an orthopedic surgeon. Statistical evaluation was done with the Dice coefficient and the mean average precision) score. According to the humeral head structure three groups were generated: the healthy humeral head group, the edematous humeral head group, and the Hill-Sachs group (humeral heads with Hill-Sachs lesions). RESULTS: In the test images, 81 humeral heads were healthy, 100 were edematous, and 38 had a Hill-Sachs lesion. According to the Dice metric, the overall success rate of Mask R-CNN configuration was 96.47 and 93.87% for the segmentation of the humeral head and scapula, respectively, and 95.86 and 92.35% for an intersection over union of 0.5 according to the mean average precision. According to the Dice metric, the segmentation success of the humerus and scapula of the healthy group was 94.58 and 97.42%, the segmentation success of the edematous humerus group was 93.56 and 96.53%, and the segmentation success of the Hill-Sachs group was 93.47 to 95.48%. The segmentation success of scapula in the case of discontinuity was 92.86% according to Dice metric. CONCLUSION: Mask R-CNN-based humerus and scapula segmentation provided promising results compared to manual segmentation of an expert. Mask R-CNN overcomes the problem of discontinuous edges and Rician noise in axial PD-weighted shoulder magnetic resonance imaging.