SPECT/CT of Total Ankle Arthroplasty.

Use of SPECT/CT (Single Photon Emission Computed Tomography/Computed Tomography) is increasing providing additional information in patients with inconclusive clinical examination and unremarkable imaging findings presenting with chronic pain after total ankle arthroplasty. To differentiate the cause of pain after total ankle arthroplasty can be challenging. SPECT/CT combines structural and metabolic imaging as a hybrid tool leading to higher specificity and overall diagnostic accuracy presumably in cases of gutter impingement, prosthetic loosening, and osteoarthritis of adjacent joints. Moreover, SPECT/CT can complement diagnostic work up in periprosthetic joint infections. Basal tracer enhancement has to be considered for the interpretation of imaging findings.

Cone-Beam Weight-Bearing Computed Tomography of Ankle Arthritis and Total Ankle Arthroplasty.

Weight-bearing computed tomography has multiple advantages in evaluating the hindfoot and ankle. It can assess hindfoot and ankle alignment, pathology in ankle arthritis, and complications related to total ankle replacements. It is an essential tool in ankle osteoarthritis diagnostic, preoperative planning, and total ankle replacement outcomes. It allows for better accuracy and reproducibility of alignment and implant size. In addition, it has the potential to more assertively detect complications related to weight bearing.

A gender and size specific evaluation of Grammont-type inlay versus lateralizing onlay stem designs in achieving lateralization and distalization in reverse shoulder arthroplasty.

INTRODUCTION: In reverse shoulder arthroplasty (RSA) new designs enable greater amounts of lateralization to prevent instability and scapular notching and increase range of motion, however, excessive lateralization leads to stress upon the acromion that can result in scapular spine fatigue fractures. Aim of this study was to gender- and size-specifically assess the influence of glenosphere size and different humeral designs on lateralization, distalization, and bony impingement-free range of motion (ROM) in patients undergoing RSA. METHODS: Computed tomography scans from 30 osteoarthritic patients (f:15, m:15) and 20 cuff tear arthropathy patients (f:10, m:10) were used to virtually simulate RSA implantation. The efficacy of an inlay Grammont-type system vs. an onlay lateralizing system combined with different glenosphere sizes (36 mm vs. 42 mm) in achieving ROM, lateralization, and distalization was evaluated. Moreover, gender and patient's constitution were correlated to humeral size by radiologically measuring the best-fit circle of the humeral head. RESULTS: A different amount of relative lateralization was achieved in both genders using large glenospheres and onlay designs. Latter yielded a higher ROM in all planes for men and women with a 42 mm glenosphere; with the 36 mm glenosphere, an increased ROM was observed only in men. The 155° inlay design led to joint medialization only in men, whereas all designs led to lateralization in women. When adjusting the absolute amount of lateralization to humerus' size (or patient's height), regardless of implant type, women received greater relative lateralization using 36 mm glenosphere (inlay: 1%; onlay 12%) than men with 42 mm glenosphere (inlay: -3%; onlay: 8%). CONCLUSION: The relative lateralization achieved using onlay design is much higher in women than men. Small glenospheres yield greater relative lateralization in women compared to large glenospheres in men. Humeral lateralization using onlay designs should be used cautiously in women, as they lead to great relative lateralization increasing stress onto the acromion. LEVEL OF EVIDENCE: Basic Science Study, Computer Modeling.

Imaging evaluation of extraarticular posterior loose bodies in varus ankle osteoarthritis.

Purpose: Multiple loose bodies (LBs) are often found in patients with varus ankle osteoarthritis (OA). This study aimed to investigate the characteristics of extra-articular posterior ankle LBs in patients with varus ankle OA. We also sought to determine whether there were variations in the characteristics of LBs according to the degree of ankle OA. Methods: We retrospectively reviewed 50 patients who had appeared posterior extraarticular LBs on preoperative ankle imaging among the patients who underwent operative treatment for varus ankle OA from March 2011 to February 2023. We categorized the entire patient cohort into four groups according to the degree of ankle arthritis (Takakura stage II, IIIA, IIIB, and IV). Size, number, and location of LBs were evaluated using preoperative computed tomography and magnetic resonance imaging. Results: 142 LBs were identified (mean size: 11.5 mm); 76.8% were located within the flexor hallucis longus (FHL) tendon sheath, 20.4% in the posterior recess, and 2.8% in the flexor digitorum longus tendon sheath. Average LB size was significantly larger in Takakura stage IIIB and IV patients (p < .05), and the LB number was significantly lower in stage II patients (p = .013). Conclusion: Extra-articular posterior LBs in varus ankle OA are predominantly located within the FHL tendon sheath and were larger in Takakura stages IIIB and IV patients.Level of Evidence: Level III. Retrospective comparative study.

Unveiling MRI-based structural phenotypes in temporomandibular joint osteoarthritis: implications for clinical practice and research.

INTRODUCTION: Osteoarthritis (OA) is a progressive degenerative disease characterized by the gradual degradation of cartilage, remodeling of subchondral bone, synovitis, and chronic pain. This condition impacts various large and small joints, including the temporomandibular joint (TMJ). However, addressing OA, particularly in impeding or reducing disease progression, is challenging due to its clinical and imaging heterogeneity. Authors are increasingly suggesting that this heterogeneity involves different phenotypes or subpopulations, discernible by variations in the disease's pathophysiology and structural manifestations. Even within the TMJ, these phenotypes may display distinct clinical features, laboratory parameters, biochemical markers, and imaging criteria. Recent research has proposed MRI as a reference standard for TMJ OA, highlighting its substantial agreement with histopathological changes. MRI-based phenotypes offer a promising avenue for understanding disease progression and treatment response, potentially providing valuable insights for prognosis and treatment planning. OBJECTIVE: This article introduces the ROAMES-TMJ (Rapid OsteoArthritis MRI Eligibility Score for TMJ) to assess the structural eligibility of individuals for inclusion in TMJ OA clinical trials.

Interposition of Free Vascularized Fascia Into the Trapezial Resection Cavity for the Surgical Treatment of Trapeziometacarpal Osteoarthritis.

BACKROUND: Trapeziometacarpal osteoarthritis has been treated with interposition of autologous fascia into the trapezial resection cavity to prevent scaphometacarpal impingement with suboptimal results. Autologous fascia may undergo necrosis and gradual shrinkage due to avascularity. We propose vascularization of the interposed fascia using microvascular techniques as a new alternative to achieve a durable graft with sufficient soft tissue volume. PATIENTS AND METHODS: In this retrospective study, 11 surgeries for 8 patients (6 women, 2 men) (5 primary and 6 revision cases) were performed using vascularized fascial grafts from the anterolateral thigh for interposition in the trapezial resection cavity with microvascular anastomosis for revascularization. Subjective assessment included the short version of the Quick Disabilities of the Hand, Shoulder and Arm and patient related hand wrist evaluation scores. Objective assessment included strength and range of motion measurements. Radiographs were obtained preoperatively and at each follow-up visit. An MRI was done at a mean of 19 months postoperatively. RESULTS: The size of the harvested fascial grafts was 2 × 2-3 cm with a thickness of 1.5-2 cm. There were no postoperative complications apart from one seroma in the graft harvest site. The mean clinical and radiologic follow-up was 2 years and 8 months. The procedure provided pain relief PRWHE pain 32 (SD 13)-9 (SD 12), p < 0.0001, increased tip pinch strength 4 kg (SD3)-6 kg (SD2), p < 0.05, and improved overall function PRWHE 60 (SD28)-16 (SD21), p < 0.0001 and QuickDash 50 (SD21)-13 (SD17), p < 0.0001. Radiographs demonstrated maintenance of the scaphometacarpal space, while MRI scans showed the presence of mildly edematous interposed tissue within the resection cavity. CONCLUSIONS: Although technically demanding, vascularized fascia presents an attractive alternative for the treatment of trapeziometacarpal osteoarthritis. It may be particularly advantageous in complex cases requiring revision surgery and in young patients with high functional demands.

Increased femoral cartilage thickness in acne patients using isotretinoin: could it be a sign of early osteoarthritis?

Vitamin A derivatives have inhibitory effects on cartilage tissue, such as decreasing chondrocyte proliferation and collagen synthesis, and increasing the loss of glycosaminoglycans and proteoglycans. Therefore, isotretinoin (a vitamin A derivative) may play a role in the pathogenesis of cartilage-related diseases like osteoarthritis by affecting the balance of cartilage tissue. The aim of this study was to evaluate the distal femoral cartilage thickness in acne patients under the systemic isotretinoin therapy and to determine whether it constitutes a risk factor for the development of osteoarthritis. The study included 52 patients (42 female, 10 male, mean age 23.31 ± 3.89 years) who were prescribed systemic isotretinoin for acne and completed at least 3 months of treatment, along with 45 healthy controls ((35 female, 10 male, mean age 23.85 ± 4.77 years). Bilateral distal femoral cartilage thickness was measured by ultrasonography before isotretinoin treatment and after the completion of the third month of treatment. After treatment, a statistically significant increase was found in the thickness of the right medial, right lateral, left medial, left lateral, and left intercondylar cartilage (p = 0.014, 0.012, 0.019, 0.027, 0.002, respectively). There was also an increase in the right intercondylar cartilage thickness, but this was not statistically significant (p = 0.1). Systemic isotretinoin seems to make cartilage thicker. The increase in femoral cartilage thickness observed after short-term isotretinoin treatment might be an indicator of very early-stage osteoarthritis. Extended follow-up studies with larger participant pools are necessary to substantiate this result.

Postoperative Radiographic Outcomes Following Abduction-Extension Metacarpal Osteotomy: A Comparison between Early and Advanced Carpometacarpal Arthritis.

Background: This study aimed to investigate the effect of thumb metacarpal osteotomy on dorsal subluxation of the carpometacarpal (CMC) joint and compare the effects of early and advanced osteoarthritis (OA). Methods: We retrospectively reviewed 42 thumbs of 37 patients who underwent metacarpal osteotomy with a postoperative extension angle of 90° or more between January 2018 and October 2021 and were followed up for more than 2 years. The thumbs were classified into two groups: early OA (Eaton stage I or II) and advanced OA (Eaton stage III). We measured the reduction ratio, which was defined as the ratio of improvement in dorsal subluxation, at 3 months and 1 year postoperatively, and at the latest follow-up. We statistically compared the reduction ratio between the two groups and investigated the factors affecting the reduction ratio using correlation analysis. Results: The reduction ratio was significantly higher in the early OA group than in the advanced OA group at 3 months after surgery, whereas no significant difference was found between the two groups at 1 year after surgery and at the latest follow-up. A significant positive correlation was detected between the reduction ratio and the postoperative extension angle. Conclusions: First metacarpal osteotomy reduces dorsal subluxation in both early- and advanced-stage CMC OA. This procedure yields immediate marked reduction in early-stage OA, while improvement of the subluxation progressed gradually in advanced-stage OA. Level of Evidence: Level IV (Therapeutic).

Accuracy of Implant Placement Based on Three-Dimensional Preoperative Planning in Total Elbow Arthroplasty.

Background: Accurate implant placement in the optimal position is important to obtain favourable clinical outcomes and prevent complications in total joint arthroplasty. We aimed to assess the accuracy of implant placement based on three-dimensional (3D) preoperative planning for unlinked total elbow arthroplasty (TEA) and to clarify the effect of implant placement on clinical outcomes. Methods: This study included 20 patients (22 elbows, 17 with rheumatoid arthritis and 5 with osteoarthritis, with a mean follow-up period of 47 months) who underwent TEA with an unlinked-type implant after computed tomography (CT)-based 3D preoperative planning. Implant placement was planned preoperatively and several parameters were set to reflect it intraoperatively. TEA was performed based on the plan, and postoperative CT was conducted to evaluate differences in implant placement by comparing the preoperative plan and postoperative implant placement. Furthermore, we evaluated the relationship between implant placement differences and postoperative clinical outcomes, including range of motion, Visual Analogue Scale, Mayo Elbow Performance Score 1 year after surgery and complications at the last follow-up. Results: The mean absolute translation was within 2 mm, the mean absolute tilt was within 4°, the mean absolute rotation of the humeral component was within 4° and the mean absolute rotation of the ulnar component was 10.2° ± 6.8°. In the ulnar components, 15/22 (68%) cases were externally rotated, and the mean external rotation was 7.1° ± 10.2°. We defined the absolute ulnar component's rotational difference of more than 10° as a 'malrotation' group (n = 8) and 10° or less as a 'control' group (n = 14). We compared the clinical outcomes between both groups, however, no significant differences were observed in clinical outcomes and complications. Conclusions: We observed notable malrotation in the postoperative positioning of the ulnar component. Intraoperative support devices may be necessary to accurately reproduce the preoperative plan in the surgical field. Level of Evidence: Level IV (Therapeutic).

The natural history of marginal erosions in hands with and without osteoarthritis.

INTRODUCTION/OBJECTIVES: Among people with or without hand osteoarthritis, we aimed to identify characteristics of people (e.g., age and gender) with marginal erosions (MEs). We also examined changes in MEs during 48 months. We described radiographic severity and progression among joints with MEs, changes in MEs, or central erosions (CEs). DESIGN: We studied participants from the Osteoarthritis Initiative with baseline and 48-month hand radiographs. A radiologist and rheumatologist evaluated the radiographs for disease severity (Kellgren-Lawrence grades) and erosions (central or marginal), respectively. We used descriptive statistics to characterize participants and calculated frequencies at the joint level. RESULTS: Of the 3558 participants, 89 had a ME at baseline. People with MEs were more often male, older, and ever (former and current) smokers than those without a ME. There was no difference in inflammatory biomarkers or the presence of hand pain between individuals with and without a baseline ME. Almost all hands had only one ME (80%), whereas only 50% of individuals with CEs had only one CE at baseline. Compared to CEs, MEs appeared more frequently in joints without osteoarthritis (54% vs. < 1%). Approximately 18% of joints with an ME progressed in Kellgren-Lawrence grade versus 4% without ME. Among the joints with an ME at baseline, 10% resolved by 48 months. Less than 0.1% of joints developed a new ME. CONCLUSION: MEs appear to be distinct from CEs. MEs are predominantly present in males, isolated to one specific joint without osteoarthritis within a hand, and possibly predictive of radiographic progression. Key Points • Marginal erosions appear to be distinct from central erosions. • Most marginal erosions occur in joints without radiographic osteoarthritis. • Radiographic progression but not hand pain is more common in joints with a marginal erosion than without one.

Research progress of ultrasound in accurate evaluation of cartilage injury in osteoarthritis.

Osteoarthritis (OA) is a prevalent cause of joint algesia, loss of function, and disability in adults, with cartilage injury being its core pathological manifestation. Since cartilage damage is non-renewable, the treatment outcome in the middle and late stages of OA is unsatisfactory, which can be minimized by changing lifestyle and other treatment modalities if diagnosed and managed in the early stages, indicating the importance of early diagnosis and monitoring of cartilage injury. Ultrasound technology has been used for timely diagnosis and even cartilage injury treatment, which is convenient and safe for the patient owing to no radiation exposure. Studies have demonstrated the effectiveness of ultrasound and its various quantitative ultrasound parameters, like ultrasound roughness index (URI), reflection coefficient (R), apparent integrated backscatter (AIB), thickness, and ultrasound elastography, in the early and accurate assessment of OA cartilage pathological changes, including surface and internal tissue, hardness, and thickness. Although many challenges are faced in the clinical application of this technology in diagnosis, ultrasound and ultrasound-assisted techniques offer a lot of promise for detecting early cartilage damage in OA. In this review, we have discussed the evaluation of ultrasonic cartilage quantitative parameters for early pathological cartilage changes.

Long-term outcomes after capitate fractures: a median 16-year follow-up.

INTRODUCTION: The long-term effects of a capitate fracture are unknown. The aim of this study was to assess both clinical and radiological long-term outcomes after a capitate fracture. MATERIALS AND METHODS: From a cohort of 526 consecutive patients with post traumatic radial sided wrist pain, 23 were identified diagnosed with a capitate fracture. 16 of these (11 males and 5 females) with a median age at injury of 17.5 years (range 11-27 years) were eligible for a follow-up after a median of 16 years (range 8 to 17 years). In this study patients were examined using conventional radiographs, computed tomography (CT) and magnetic resonance imaging (MRI) at the time of injury and with CT at the follow-up. At follow-up radiological signs of osteoarthritis were graded in four stages and clinical outcome was evaluated by measuring range of wrist motion and grip and pinch strength. The subjective outcome was assessed using DASH and PRWE questionnaires. RESULTS: Five patients had isolated capitate fractures and 11 had concomitant fractures, 10 of which had a simultaneous scaphoid fracture. 14 patients had been treated non-surgically in a cast and two patients were treated surgically. None of the fractures were visible on conventional radiographs at the time of injury. At follow-up all fractures had healed without signs of avascular necrosis. In one patient, CT examination revealed osteoarthritis between the capitate and lunate. This did not cause clinical symptoms. Functional impairments and pain scores were low: median DASH score 0, median PRWE 3 and median VAS pain score 0. We found no impairment in range of motion or grip and pinch strength. CONCLUSIONS: At a median of 16-year follow-up, patients with a capitate fracture report normal self-assessed hand function as well as good wrist motion and strength. The risk of development of posttraumatic arthritis in the joints around the capitate is low.

What is New in Osteoarthritis Imaging?

Osteoarthritis (OA) is the leading joint disorder globally, affecting a significant proportion of the population. Recent studies have changed our understanding of OA, viewing it as a complex pathology of the whole joint with a multifaceted etiology, encompassing genetic, biological, and biomechanical elements. This review highlights the role of imaging in diagnosing and monitoring OA. Today's role of radiography is discussed, while also elaborating on the advances in computed tomography and magnetic resonance imaging, discussing semiquantitative methods, quantitative morphologic and compositional techniques, and giving an outlook on the potential role of artificial intelligence in OA research.

Effect of the Sauvé-Kapandji method on the wrist contact surface for distal radial ulnar joint disorders.

BACKGROUND: The Sauvé-Kapandji (S-K) method is a surgical procedure performed for chronic deformities of the distal radial ulnar joint (DRUJ). Changes to the joint contact surface from pre- to postoperatively under physiological in vivo conditions have not yet been determined for this useful treatment. The aim of the present study was therefore to compare the articular contact area of the wrist joint between before and after the S-K method for DRUJ disorders. METHODS: The SK method was performed for 15 patients with DRUJ osteoarthritis and ulnar impaction syndrome. We calculated the Mayo Wrist Score as the patient's clinical findings and created 3-dimensional bone models of cases in which the S-K method was performed and calculated the contact area and shift in the center of the contact area using customized software. RESULTS: The Mean modified Mayo Wrist Score improved significantly from 60.3 preoperatively to 80.3 postoperatively (P < 0.01). Scaphoid contact area to the radius increased significantly from 112.6 ± 37.0 mm2 preoperatively to 127.5 ± 27.8 mm2 postoperatively (P = 0.03). Lunate contact area to radius-ulna was 121.3 ± 43.3 mm2 preoperatively and 112.5 ± 37.6 mm2 postoperatively, but this decrease was not significant (P = 0.38). Contact area ratio of scaphoid to lunate increased significantly from 1.01 ± 0.4 preoperatively to 1.20 ± 0.3 postoperatively (P = 0.02). Postoperative translations of the center of the scaphoid and lunate contact areas were decomposed into ulnar and proximal directions. Ulnar and proximal translation distances of the scaphoid contact area were 0.8 ± 1.7 mm and 0.4 ± 0.6 mm, respectively, and those of the lunate contact area were 1.1 ± 1.7 mm and 0.4 ± 1.1 mm, respectively. This study revealed changes in wrist contact area and center of the contact area before and after the S-K method. CONCLUSION: These results may accurately indicate changes in wrist joint contact area from pre- to postoperatively using the S-K method for patients with DRUJ disorder. Evaluation of changes in contact area due to bone surface modeling of the wrist joint using 3DCT images may be useful in considering surgical methods.

Prognostic factors and the value of radiographic osteoarthritis for persistent complaints after referral for ankle radiography.

BACKGROUND: Ankle symptoms are a common reason to consult the general practitioner and often persist for years. In a population referred for ankle radiography, the prevalence of radiographic osteoarthritis (OA) is substantial, but its additional predictive value for persistent symptoms is unknown. Therefore, we examined the prognosis of symptoms 2-3 years after referral for ankle radiography, assessed clinical prognostic factors, and the additional predictive value of radiographic OA for persistent ankle complaints. METHODS: We included 893 adults referred for ankle radiography and studied the following candidate prognostic factors at baseline: age, sex, body mass index (BMI), referral for chronic complaints (>3 months), pain during activity (NRS-11) and presence of stiffness and functional loss as predominant symptom. X-rays were scored for radiographic OA. After 2-3 years participants were invited for a follow-up questionnaire including persistence of ankle complaints. To assess prognostic factors for persistent complaints, uni- and multivariable logistic regression were used. RESULTS: Of the 194 responders at follow-up, ankle complaints persisted in 71(36.6 %). BMI (OR 1.08; 95 % CI 1.01-1.15), stiffness as predominant symptom (OR 1.69; 95 % CI 0.89-3.21), and chronic complaints (OR 2.84; 95 % CI 1.45-5.57) were in the initial model for persistent complaints (AUC=0.69). After adding radiographic OA (OR 2.36; 95 % CI 1.01-5.50), the AUC of the final model became 0.70. CONCLUSION: Ankle complaints persist in a considerable proportion of patients 2-3 years after referral for ankle radiography. BMI, chronic complaints and radiographic OA are prognostic factors for persistent complaints, but the additional predictive value of radiographic OA on top of clinical factors is negligible.

Multiscale-temporal Feature Extraction and boundary confusion alleviation for VAG-based fine-grained multi-grade osteoarthritis deterioration monitoring.

BACKGROUND AND OBJECTIVE: Multi-grade osteoarthritis (OA) deterioration monitoring in the daily paradigm using Vibroarthrography (VAG) is very challenging due to two difficulties: (1) the composition of VAG signals is complex in the daily paradigm where friction is intensified because of weight-bearing movements. (2) VAG signal samples near the decision boundary of adjacent deterioration grades are easy to be misclassified. The majority of existing works only focus on the binary classification of OA, providing inadequate assistance in instructing physicians to develop treatment plans based on the presence or absence of OA. Thus, we propose a novel framework for fine-grained multi-grade OA deterioration monitoring in the daily paradigm. METHODS: We propose an end-to-end deep learning framework termed Fine-grained Multi-grade OA Deterioration Monitor (FMOADM), which consists of Multiscale-temporal Feature Extraction (MTFE) and Confusion-Free Master-Slave (CF-MS) Classification. Specifically, MTFE is adopted to extract multiscale-temporal discriminative features from the complicated VAG signals. And center loss is introduced by CF-MS to alleviate confusion at the boundary of adjacent deterioration grades in the feature space. Meanwhile, a master-slave structure is proposed for further fine-grained classification, where the master classifier integrates a channel attention mechanism and the slave classifier is designed to update MTFE parameters. As a result, the proposed method ensures fine-grained multi-grade OA monitoring performance via multiscale-temporal discriminative features and boundary confusion alleviation. RESULTS: Experimental results on the VAG-OA dataset demonstrate that our framework outperforms counterpart methods in the daily paradigm. The proposed framework achieved 78% in precision, obtaining an 8% improvement over the state-of-the-art method. CONCLUSION: The proposed framework benefits efficient multi-grade OA deterioration monitoring, empowering physicians to develop treatment plans based on fine-grained monitoring results. It takes knee joint health monitoring in daily activities a step further toward feasible.

Effective shape of ball-and-socket prosthesis in restoring range of thumb motion for total thumb carpometacarpal joint arthroplasty: three-dimensional motion analysis.

PURPOSE: Total joint arthroplasty (TJA) has often been used to treat thumb carpometacarpal (CMC) osteoarthritis (OA). However, guidelines for the CMC prosthesis shape remain unclear. This study aimed to identify the effective shape of a ball-and-socket prosthesis in restoring the range of thumb motion after TJA. METHODS: The participants were 10 healthy young adult men (22-32 years; 26.8 ± 3.57 [mean ± SD]). CT scans were performed in eight static limb positions during abduction and flexion. We defined three design variables (offset R, height H, and neck rotation angle Φ) as the variables that determine the basic shape of the ball-and-socket prosthesis. The ideal values of these design variables were examined based on the results of a 3D motion analysis, which evaluated the change in the posture of the first metacarpal (r, h, and φ corresponding to R, H, and Φ, respectively) relative to the center of rotation (COR) during abduction and flexion. We also simulated the effect of these design variables on the range of thumb motion after TJA using 3D CAD. RESULTS: We found that the values of r and h averaged over all limb positions were 6.92 ± 1.60 mm and 51.02 ± 1.67 mm, respectively, showing that these values remained constant regardless of limb position. In contrast, φ changed significantly. The simulation results indicated that Φ affected the range of thumb motion after TJA, and Φ = 0° relatively reproduced all limb positions compared to other values. CONCLUSION: Our results suggested that the desirable values of R and H were the average of r and h over several limb positions and that Φ = 0° was effective in restoring the range of thumb motion after TJA. Our results will provide surgeons with new guidelines for selecting a prosthesis.

Deep learning classification performance for diagnosing condylar osteoarthritis in patients with dentofacial deformities using panoramic temporomandibular joint projection images.

OBJECTIVE: The present study aimed to assess the consistencies and performances of deep learning (DL) models in the diagnosis of condylar osteoarthritis (OA) among patients with dentofacial deformities using panoramic temporomandibular joint (TMJ) projection images. METHODS: A total of 68 TMJs with or without condylar OA in dentofacial deformity patients were tested to verify the consistencies and performances of DL models created using 252 TMJs with or without OA in TMJ disorder and dentofacial deformity patients; these models were used to diagnose OA on conventional panoramic (Con-Pa) images and open (Open-TMJ) and closed (Closed-TMJ) mouth TMJ projection images. The GoogLeNet and VGG-16 networks were used to create the DL models. For comparison, two dental residents with < 1 year of experience interpreting radiographs evaluated the same condyle data that had been used to test the DL models. RESULTS: On Open-TMJ images, the DL models showed moderate to very good consistency, whereas the residents' demonstrated fair consistency on all images. The areas under the curve (AUCs) of both DL models on Con-Pa (0.84 for GoogLeNet and 0.75 for VGG-16) and Open-TMJ images (0.89 for both models) were significantly higher than the residents' AUCs (p < 0.01). The AUCs of the DL models on Open-TMJ images (0.89 for both models) were higher than the AUCs on Closed-TMJ images (0.72 for both models). CONCLUSIONS: The DL models created in this study could help residents to interpret Con-Pa and Open-TMJ images in the diagnosis of condylar OA.

Cartilage compositional MRI-a narrative review of technical development and clinical applications over the past three decades.

Articular cartilage damage and degeneration are among hallmark manifestations of joint injuries and arthritis, classically osteoarthritis. Cartilage compositional MRI (Cart-C MRI), a quantitative technique, which aims to detect early-stage cartilage matrix changes that precede macroscopic alterations, began development in the 1990s. However, despite the significant advancements over the past three decades, Cart-C MRI remains predominantly a research tool, hindered by various technical and clinical hurdles. This paper will review the technical evolution of Cart-C MRI, delve into its clinical applications, and conclude by identifying the existing gaps and challenges that need to be addressed to enable even broader clinical application of Cart-C MRI.