Joint Space Research Articles

Imaging of Sacroiliac Pain: The Current State-of-the-Art.

Pain in the sacroiliac (SI) region is a common clinical manifestation, often caused by diseases involving the SI joints. This is typically due to inflammation or degenerative changes, while infections or cancer are less frequent causes. The SI joint is challenging to image accurately because of its distinct anatomical characteristics. For an accurate diagnosis, conventional radiography often needs to be supplemented with more precise methods such as magnetic resonance imaging (MRI) or computed tomography (CT). Sacroiliitis, a common presenting feature of axial spondyloarthritis (axial SpA), manifests as bone marrow edema, erosions, sclerosis, and joint space narrowing. Septic sacroiliitis and repetitive stress injuries in sports can also cause changes resembling inflammatory sacroiliitis. Other conditions, such as osteitis condensans ilii (OCI), can mimic the radiologic characteristics of sacroiliitis. Inflammatory lesions are diagnosed by concurrent erosions, hyperostosis, and ankylosis. Ligament ossifications or mechanical stress can also result in arthritic disorders. Determining the exact diagnosis can be aided by the distribution of the lesions. Inflammatory lesions can affect any part of the articulation, including the inferior and posterior portions. Mechanical lesions, such as those seen in OCI, often occur in the anterior middle region of the joint. In cases of idiopathic skeletal hyperostosis, ligament ossification is found at the joint borders. This pictorial essay describes common SI joint problems, illustrated with multimodal imaging data. We, also, discuss strategies for selecting the best imaging modalities, along with imaging pitfalls, key points, and approaches for treating patients with suspected inflammatory back pain.

Study on ultrasound-enhanced molecular transport in articular cartilage.

Local intra-articular administration with minimal side effects and rapid efficacy is a promising strategy for treating osteoarthritis(OA). Most drugs are rapidly cleared from the joint space by capillaries and lymphatic vessels before free diffusion into cartilage. Ultrasound, as a non-invasive therapy, enhances molecular transport within cartilage through the mechanisms of microbubble cavitation and thermal effects. This study investigated the mass transfer behavior of solute molecules with different molecular weights (479 Da, 40 kDa, 150 kDa) within porcine articular cartilage under low-frequency ultrasound conditions of 40 kHz and ultrasound intensities of 0.189 W/cm2 and 0.359 W/cm2. The results revealed that under the conditions of 0.189 W/cm2 ultrasound intensity, the mass transfer concentration of solute molecules were higher compared to passive diffusion, and with an increase in ultrasound intensity to 0.359 W/cm2, the mass transfer effect within the cartilage was further enhanced. Ultrasound promotes molecular transport in different layers of cartilage. Under static conditions, after 2 h of mass transfer, the concentration of small molecules in the superficial layer is lower than that in the middle layer. After applying ultrasound at 0.189 W/cm2, the molecular concentration in the superficial layer significantly increases. Under conditions of 0.359 W/cm2, after 12 h of mass transfer, the concentration of medium and large molecules in the deep layer region increased by more than two times. In addition, this study conducted an assessment of damage to porcine articular cartilage under ultrasound exposure, revealing the significant potential of low-frequency, low-intensity ultrasound in drug delivery and treatment of OA.

Occlusal splint therapy- myth or fact? -A case report

The term Temporomandibular Joint Disorders (TMD) refers to a group of intricate disorders with a variety of etiologies that frequently call for multimodal therapy strategies. Treatment of TMDs requires careful diagnosis and treatment planning to resolve occlusal and functional problems. In contemporary dental practice, splint therapy can be used as an effective and conservative means of treatment of TMDs. In this case report occlusal splint therapy was used to treat a male patient of 27yrs age who had symptoms of TMD, including pain in the head, neck, and shoulder. After 8 months of splint therapy, a clinical examination and radiographic interpretation showed considerable changes, including decreased pain frequency, better jaw function, and radiographic evidence of altered joint spaces. This case report shows the effectiveness of occlusal splint therapy in treating temporomandibular joint disorders.

Critical evaluation of the current role of SYSADOA in the management of osteoarthritis (literature review)

Background. Osteoarthritis is a common chronic disease characterized by progressive degradation of all joint components and inflammation. The priority issue in the management of OA is sear­ching for drugs that simultaneously relieve symptoms, modify the course of the disease, and are safe for use. Symptoma­tic slow-ac­ting drugs (SYSADOA) are of considerable interest due to their potential to slow cartilage degeneration and potential osteoarthritis di­sease mo­difying effect. The purpose of the study was to ana­lyze current literature data on several types of SYSADOA, their biological role, mecha­nisms of effect on joints, effectiveness and safetye. ­Materials and methods. An analytical review of literature data was conducted using the ana­lysis of scientific databases PubMed, Web of Science, Scopus, Google Scholar for the period 2005–2024, the search was conducted using the keywords “osteoarthritis”, “SYSADOA”, “DMOAD”, “effectiveness”, “safety”. Results. Glucosamine salts (GA) and chondroitin sulfate (CS) are the most stu­died slow-acting drugs and have positive biological effects on joint tissues. Prescription salts of GA and CS have effect of pain relieve and joint function improvement as separate agents and also potentiate the effect in combination. Studies revealed limiting of cartilage volume loss and joint space narrowing – a potential DMOAD effect of these drugs. GA salts and CS drugs are safe, as they have no difference in the frequency of side effects compared to placebo. The quality of drugs largely depends on the type of raw materials and technological production process, which are not standardized now. Conclusions. The role of SYSADOA in the treatment of OA has not been definitively determined, and studies on the effectiveness of drugs such as SYSADOA and the study of their DMOAD effect are still ongoing. Further stu­dies should focus on the use of pharmacological class SYSADOA that have been properly purified and quality strictly supervised.

COMPARISON of TEMPOROMANDIBULAR JOINT SPACE and ARTICULAR EMINENCE INCLINATION in VARIOUS SKELETAL ANOMALIES

Aim: This study aims to compare the values of joint spaces and articular eminence inclinations in individuals with various skeletal anomalies. Materials and Methods: A total of 60 individuals with Class I (n=20), Class II (n=20), and Class III (n=20) anomalies were included in the study, and their cone-beam computed tomography images were utilized. In each individual, the axial sectional joint spaces, including the articular disc, were calculated three-dimensionally using computer software for both the right and left condyles. Additionally, the articular eminence inclinations of both the right and left sides were measured for each individual. The obtained data were statistically compared among groups using one-way analysis of variance and within groups for the right and left values using paired t-tests (p

Comparative Evaluation of Temporomandibular Joint Parameters in Unilateral and Bilateral Cleft Lip and Palate Patients Using Cone-Beam CT: Focus on Growing vs. Non-Growing Subjects.

Morphological differences in the temporomandibular joint (TMJ) are crucial for the treatment of patients with cleft lip and palate (CLP). This study aims to evaluate and compare the TMJ parameters in patients with unilateral and bilateral CLP across growing and non-growing age groups using cone-beam computed tomography (CBCT). CBCT records from 57 patients (23 males and 34 females) aged 6-50 years with a diagnosed unilateral or bilateral CLP were analyzed. Patients were categorized into four groups: growing unilateral (UGCLP), growing bilateral (BGCLP), non-growing unilateral (UNGCLP), and non-growing bilateral (BNGCLP). Measurements of TMJ parameters, including the mandibular fossa, articular eminence inclination, joint spaces, and roof thickness of the glenoid fossa, were conducted using CBCT images. Significant differences were observed in the anterior joint space (AJS) and the roof of the glenoid fossa (RGF) between growing and non-growing unilateral cleft patients. Additionally, significant discrepancies were found in the articular eminence angle when comparing the cleft and non-cleft sides within the unilateral growing group. No significant differences were observed in TMJ parameters between the right and left sides among bilateral cleft patients. The study highlights distinct TMJ morphological differences between growing and non-growing patients with CLP, emphasizing the importance of age-specific considerations in the treatment planning and growth monitoring of these patients.

CT-based comprehensive scoring system for assessing hip arthropathy in ankylosing spondylitis: feasibility study with clinical correlation.

To develop a CT-based scoring system for assessment of hip arthropathy in AS. All AS patients were prospectively recruited, consented, and underwent whole-body stereoradiographs and pelvis CT, which were assessed by two independent radiologists. Stereoradiographs were assessed according to Kellgreen-Lawrence and BASRI-h. For the Hip arthropathy CT score in AS (HACTSAS), joints were divided into 7 segments and scored for joint space, osteophytes, subchondral cysts/erosions. Patients were clinically assessed for range of motion (ROM), pain, and clinical scores (BASMI, BASFI, ASQol, BASDAI and ASDAS). Radiological scores correlations with clinical parameters were compared. ROM sensitivity and specificity for hip arthropathy (BASRI-h ≥ 2) were calculated. Sample included 112 patients, with 36/112 females and 76/112 males. Average age was 51.0 ± 11.2 years and mean duration of AS was 20.9 ± 9.6 years. ICC for HACTSAS, Kellgreen-Lawrence and BASRI-h were 0.89, 0.89 and 0.82 respectively. HACTSAS showed moderate absolute correlation with ROM (ρ=-0.41) and BASMI (ρ = 0.45), and weak with pain (ρ = 0.18) and BASFI (ρ = 0.25). BASRI-h and Kellgreen-Lawrence exhibited moderate correlation with ROM (ρ=-0.44 and ρ=-0.40, respectively), weak with pain (ρ=-.27and ρ=-0.23, respectively) and BASFI (ρ=-0.16 and ρ=-0.18, respectively), but only weak with BASMI (ρ=-0.34 and ρ=-0.36, respectively). Internal rotation <15°, abduction <31°, and intermalleolar distance <75cm were, respectively, 73%, 70% and 73% sensitivity and 81%, 65% and 68% specific for hip arthropathy. HACTSAS exhibited higher correlation with BASMI and BASFI when compared with BASRI-h, but less correlation with pain and ROM. Internal rotation was the best clinical discriminator for hip arthropathy.

Sonographic assessment of ulno‐humeral joint instability

AbstractThe ulnar collateral ligament (UCL) of the elbow plays a crucial role in elbow stability, specifically as a valgus and rotational constraint. Injuries to the UCL are common in overhead‐throwing athletes resulting in elbow instability. A timely diagnosis of early ulno‐humeral joint space widening in the overhead‐throwing athlete is required, to inform patient management and return to play. Sonographic assessment and measurement of the ulno‐humeral joint space with and without stress, and comparison to the contralateral uninjured side provides a quantitative assessment of instability. A systematic sonographic technique for single operator stress ultrasound is outlined to improve consistency of assessment and reporting of findings.

Interobserver reliability of shoulder radiographic findings and correlation to MRI: a preliminary case series.

The aim of this study was to evaluate the interobserver reliability of measurements of the Acromiohumeral Distance (AHD) first described by Golding et al., the Critical Shoulder Angle (CSA), the Acromion Index with Glenoid Humeral (GH) and Glenoid Acromial (GA) distances, following the measuring method by Nyffeler et al., the Lateral Acromion Angle (LAA), as well as the morphology of the acromion according to Bigliani and the humeral head position according to Maloney in X-rays and MRI. Furthermore, the study assessed the correlation of measurement results in X-ray with those in MRI for AHD, CSA, GA, GH, AI, and LAA. A total of 187 patients who underwent shoulder joint X-ray and MRI examinations from 09/2016 to 05/2023 were included in the study. Patients with poor imaging quality, arthrosis or radical prior surgeries, like shoulder prosthetic surgery, status post humerus fractures, that have undergone surgery and therefore changed the anatomical features were excluded, what lead to a total study population of 78. X-ray measurements were performed by two observers in the true anteroposterior view, so that the humeral head and the glenoid are shown without overlap, providing a clear view into the joint space. MRI measurements were performed in oblique coronal MRI slices, using the most accurately depicted glenoid surface as a landmark. Interobserver measurement results showed a significance with p < 0.001 for the assessment of acromion type according to Bigliani, humeral head offset assessment according to Maloney, and AHD. No significance was found for interobserver reliability in measuring LAA. Additionally, there was a high correlation of measurement results in X-ray with measurements in MRI for, CSA, GH/GA, and consequently AI, a good correlation for AHD but no correlation could be shown for LAA. These findings provide valuable insights into the robustness of radiological parameters for evaluating shoulder pathology, offering promising prospects for clinical applications and further research. Nevertheless, the specific methodological considerations and patient characteristics should be taken into account when interpreting the results to ensure their accurate application in clinical practice.

Injectable Regenerated Silk Fibroin Micro/Nanosphere with Enhanced Permeability and Stability for Osteoarthritis Therapy.

In the therapy of early-stage osteoarthritis, to accomplish full infiltration of subchondral bone and cartilage, and to target osteoclast and chondrocyte simultaneously remain challenges in biomaterials design. Herein, a novel hierarchical drug delivery system is introduced, with micrometer-scale outer layer spheres composed of regenerated silk fibroin, characterized by connected porous structure through the n-butanol and regenerated silk fibroin combined emulsion route and freezing method. The design effectively resists clearance from the joint cavity, ensuring stable delivery and prolonged residence time within the joint space. Additionally, the system incorporates phenylboronic acid-enriched silk fibroin nanoparticles, stabilized through chemical cross-linking, which encapsulate isoliquiritin derived from Glycyrrhiza uralensis. These nanoparticles facilitate complete penetration of the cartilage extracellular matrix, exhibit pH-responsive behavior, neutralize reactive oxygen species, and enable controlled drug release, thereby enhancing therapeutic efficacy. The in vitro and in vivo experiments both demonstrate that the composite micro/nanospheres not only inhibit osteoclastogenesis with bone loss in subchondral bone and osteophyte formation, but also mitigate chondrocytes apoptosis, reduce oxidative stress associated with cartilage degeneration, and ameliorate neuropathic hyperalgesia, with the underlying mechanisms being elucidated. The study indicates that such an injectable strategy combining organic biomaterials with Chinese medicine holds substantial promise for the treatment of early osteoarthritis.

Quantifying uncertainty in rock mass properties: Implications for GSI, RMi, and RMR assessments

Probability-based empirical methods were employed as an alternative approach to predicting uncertainties associated with rock mass properties. The focus was on developing probabilistic spreadsheets to forecast rock mass classification indexes. Histograms were constructed to describe the best distribution in predicting rock mass properties. The developed models also offer utility in predicting the impact of discontinuities within the rock mass on rock strength and rock mass classification systems. Statistical analyses identified volumetric joint count, joint spacing, joint frequency, and rock strength as the most influential parameters. Moreover, the statistical analysis revealed varying degrees of correlation among different rock mass properties. While some properties demonstrated significant correlations suitable for modelling, others did not align well with any correlation model. The results highlight the need for a comprehensive approach to rock mass characterization, considering multiple factors beyond volumetric joint count. Geological complexities, including tectonic activity and weathering processes, may obscure direct correlations. These results emphasize the importance of empirical modelling and detailed site investigations for accurate assessment of rock mass quality and stability in the Himalaya.

Investigating the relationship between radiographic joint space width loss and deep learning-derived magnetic resonance imaging-based cartilage thickness loss in the medial weight-bearing region of the tibiofemoral joint

ObjectiveTo investigate the relationship between measures of radiographic joint space width (JSW) loss and magnetic resonance imaging (MRI)-based cartilage thickness loss in the medial weight-bearing region of the tibiofemoral joint over 12–24 months. To stratify this relationship by clinically meaningful subgroups (sex and pain status). DesignWe analyzed a subset of knees (n ​= ​256) from the Osteoarthritis Initiative (OAI) likely in early stage OA based on joint space narrowing (JSN) measurements. Natural logarithm transformation was used to approximate near normal distributions for JSW loss. Pearson Correlation coefficients described the relationship between ln-transformed JSW loss and several versions of deep learning-derived MRI-based cartilage thickness loss parameters (minimum, maximum, and mean) in subregions of the femoral condyle, tibial plateau, and combined femoral and tibial regions. Linear mixed-effects models evaluated the associations between the ln-transformed radiographic and MRI-derived measures including potential confounders. ResultsWe found weak correlations between ln-transformed JSW loss and MRI-based cartilage thickness ranging from R ​= ​−0.13 (p ​= ​0.20) to R ​= ​0.26 (p ​< ​0.01). Correlations were higher (still poor) among females compared to males and painful compared to non-painful knees. Model results showed weak associations for nearly all MRI-based measures, ranging from no association to β (95% CI) ​= ​0.25 (0.11, 0.39). Associations were higher among females compared to males and minimal differences between painful and non-painful knees. ConclusionsDespite its recommended use in disease-modifying OA drug clinical trials, results suggest that JSW loss is an ineffective proxy measure of cartilage thickness loss over 12–24 months and within a localized region of the tibiofemoral joint.

Micro-Computed Tomography Analysis of the Knee in Aged Dunkin-Hartley Guinea Pigs after Intra Articular Injection.

The purpose of this protocol is to guide researchers in performing a palpation-guided technique of intra-articular knee injection in guinea pigs and assessment using micro-computed tomography. Dunkin-Hartley guinea pigs are robust models for osteoarthritis research as they spontaneously develop osteoarthritis in their knees. Intra-articular drug delivery is a common method to study the effects of an investigational drug in vivo. In humans, therapeutic agents administered via intra-articular injection can offer pain relief and delay further progression of osteoarthritis. As with any species, the introduction of a needle into a joint space has the potential to cause injury, which can result in pain, lameness, or infection. Such adverse events can compromise animal welfare, confound study results, and necessitate additional animals to achieve study objectives. As such, it is imperative to develop proper injection techniques to prevent complications, especially in longitudinal studies that require multiple, repeated intra-articular injections. Using the presented methodology, five guinea pigs received bilateral knee injections under general anesthesia. Seven days after injection, animals were humanely euthanized for analysis of osteoarthritis severity. No adverse events occurred following anesthesia or knee injections, including limping, pain, or infection. X-ray micro-computed tomography analysis of the knee can detect pathologic changes associated with osteoarthritis. Micro-computed tomography data indicates osteoarthritis is more severe in older animals, as indicated by increased bone mineral density and trabecular thickness with age. These results are consistent with histologic changes and Modified Mankin scores, an established and widely used scoring system to assess arthritis severity in these same animals. This protocol can be utilized to refine intra-articular injections in guinea pigs.

Targeting next-generation PDE4 inhibitors in search of potential management of rheumatoid arthritis and psoriasis

Immune-mediated inflammatory diseases (IMIDs) comprise a broad spectrum of conditions characterized by systemic inflammation affecting various organs and tissues, for which there is no known cure. The isoform-specific inhibition of phosphodiesterase-4B (PDE4B) over PDE4D constitutes an effective therapeutic strategy for the treatment of IMIDs that minimizes the adverse effects associated with non-selective PDE4 inhibitors. Thus, we report a new class of isoquinolone derivatives as next-generation PDE4 inhibitors for effective management of rheumatoid arthritis (RA) and psoriasis. Among the series, 8 compounds i.e. 1e, 1l, 1m, 1n, 1o, 2m, 2o and 3o showed promising PDE4B inhibition (>80 %) in vitro with IC50 ∼ 1.4–6.2 µM. The compound 1l was identified as an initial hit and was pursued for further studies. According to structure–activity relationship (SAR), an allyl group at C-4 position improved PDE4B inhibition. The correlation between in vitro activity data and binding affinities obtained via molecular docking suggested that the high-affinity binding to PDE4B is a prerequisite for the effective inhibition of PDE4B. Notably, the hit 1l showed selectivity towards PDE4B over PDE4D in vitro. Furthermore, 1l treatment (30 mg/kg) in the adjuvant-induced arthritis (AIA) rat model induced by complete Freund’s adjuvant (CFA) demonstrated anti-arthritic potential via ameliorating paw swelling and body weight, narrowing joint space, reducing excessive immune cells infiltration and pannus formation in addition to reducing mRNA expression of pro-inflammatory cytokines such as TNF-α and IL-6 in synovial tissues of experimental rats. Additionally, 1l reduced the hyper-proliferative state and colony forming potential of IMQ-induced psoriatic keratinocytes. The treatment of these cells with 1l markedly reduced the protein levels of Ki67 and mRNA levels of pro-inflammatory cytokines e.g. IL-17A and TNF-α suggesting its potent anti-psoriatic potential. Furthermore, 1l did not show any significant adverse effects when evaluated in a systematic toxicity (e.g. teratogenicity, hepatotoxicity and cardiotoxicity) studies in zebrafish at the tested concentrations (1–100 µM) and the NOAEL (no-observed-adverse-effect level) was found to be 100 µM. Thus, with promising anti-inflammatory effects both in vitro and in vivo along with PDE4B selectivity with an acceptable safety margin, 1l emerged as a new and promising inhibitor for further studies.

Time-optimal trajectory planning for manipulator based on an improved sparrow search algorithm

Abstract With the development of industrial automation, it is crucial to use manipulators for efficient painting. To solve the problem of inefficient trajectory planning of manipulators in the point-to-point painting process, this paper proposes a time-optimal trajectory planning method based on an improved sparrow search algorithm. Initially, the standard D-H parameter method is used to establish the kinematic model of the manipulator. To ensure the continuity of each joint in the manipulator, a 3-5-3 polynomial interpolation function is utilized to construct the motion trajectory in joint space. Subsequently, the improved sparrow search algorithm is utilized to optimize the point-to-point motion trajectory of the manipulator with a constraint on motion time. Finally, simulations carried out in MATLAB demonstrated that the manipulator, which was optimized by using the improved sparrow search algorithm, exhibited a significant increase in motion efficiency compared to its pre-optimization state. Additionally, the movements of the manipulator’s joints were smooth.

Cone-beam computed tomography imaging and three-dimensional analysis of midfoot joints during non-weightbearing and weightbearing in 11 healthy feet.

Studies report that Lisfranc injury is more common than thought. Several imaging methods for assessing the stability of Lisfranc injury have been described but many are impossible to standardize and not accurate enough. To present a three-dimensional (3D) method for analyzing the changes in the joint space width of the midfoot joint and the joints of the medial part of the Lisfranc complex in healthy individuals. Non-weightbearing and weightbearing cone-beam computed tomography (CBCT) images of 11 healthy feet were acquired and analyzed with 3D software. The mean range of joint space width changes of each joint was computed from the changes in individual image pairs. 3D analysis software was used to analyze the medial part of the Lisfranc complex. In this sample of healthy feet, the changes in the joint spaces in the medial part of Lisfranc complex, calculated with 3D analysis software, was less than 0.6 mm. The distance between bones increased or decreased, depending on which part of the joint surface the measurements were taken. In this study, we present a 3D analysis method to evaluate midfoot joint space width changes. Our analysis revealed that in healthy feet there are only minimal changes in the joint space width between weightbearing and non-weightbearing indicating minimal movement of the midtarsal joints. The 3D analysis of weightbearing CBCT data provides a promising tool for analyzing the small midfoot joints in a variety of conditions.

Reflection of power DOPPLER activity in the subacromial space on nocturnal pain in patients with rotator cuff tears: a cross-sectional study

BackgroundNocturnal shoulder pain is seen in patients with rotator cuff tears. The purpose of the present study was to determine whether Doppler ultrasound parameters predict the intensity of nocturnal pain in patients with rotator cuff tears. MethodsA total of 60 patients with rotator cuff tears were included. Doppler ultrasound parameters (peak systolic velocity in the anterior humeral circumflex artery, Doppler activity in the glenohumeral joint and subacromial space) and clinical parameters were examined. For the presence of nocturnal pain, the clinical parameters were compared with and without nocturnal pain. For the intensity of the nocturnal pain, a multivariate analysis of clinical parameters and nocturnal pain intensity was performed. ResultsIn all, 39 patients (65%) reported nocturnal pain, and the mean pain intensity was 47.0 (standard deviation, 26.0) on the visual analogue scale. In nocturnal pain presence analysis, Doppler activity in the subacromial space showed significant associations (p < 0.001). In nocturnal pain intensity analysis, Doppler activity in the subacromial space and diabetes showed significant associations (p < 0.001, p = 0.01, respectively). ConclusionDoppler activity in the subacromial space emerges as an independent factor associated with the presence and intensity of nocturnal pain in patients with rotator cuff tears. Our findings may provide a basis for further exploration and refinement of treatment strategies.

CT Arthrography With Traction in Femoro-Acetabular Impingement: How to Do It?

Computed tomography arthrography (CTA) highly correlates with arthroscopy in detecting labral tears, especially in patients with positive impingement tests. CTA enables the acquisition of isotropic datasets with high spatial resolution within a single acquisition. However, the hip is a close-fitting, congruent, and nearly spherical joint, with relatively thin cartilage. We describe herein a simple and cost-effective method using traction for hip CTA, with axial manual distraction, that helps overcome the usual limitations, by widening the articular joint space and thus better delineating both acetabular and femoral cartilages.

Anteromedial knee osteoarthritis (AMOA) evaluated with magnetic resonance imaging (MRI): a cohort study of 100 patients.

Magnetic resonance imaging (MRI) scans are increasingly used for knee osteoarthritis evaluation and preoperative planning before unicompartmental knee arthroplasty (UKA), and often patients already have MRI scans before their initial surgeon consultation. This highlights the need for surgeons to understand anteromedial osteoarthritis (AMOA) patterns on MRI. Hence, we aim to describe MRI findings in patients with AMOA meeting current indications for medial UKA. We analysed MRI scans from 100 knees evaluated for UKA between 2006 and 2013. Inclusion criteria comprised full-thickness medial compartment loss and intact lateral compartment joint space on preoperative radiographs. Assessment included cartilage lesions, osteophytes, meniscal damage, and anterior-cruciate ligament (ACL) status on tibial and femoral surfaces. Final decision to proceed with UKA relied on intraoperative findings, independent of MRI. Complete anteromedial tibial and femoral cartilage loss preserved posterior cartilage rims was evident in all cases. Cartilage thinning occurred in the lateral compartment in 34% of cases. While 62% displayed lateral osteophytes, only 6 exhibited small areas of full-thickness cartilage loss. ACL abnormalities varied: 27% normal, 3% ruptured, and 70% had intrasubstance high signal. Larger osteophytes in the medial (p = 0.012) and lateral (p = 0.002) intercondylar notch correlated significantly with ACL damage. All underwent medial UKA, with no evidence of areas with full lateral compartment cartilage loss intraoperatively. The MRI findings confirmed the radiographic diagnosis of bone-on-bone medial disease but highlights a range of findings in the ACL, lateral compartment, and patellofemoral joint compartment for patients who met the current x-ray and intraoperative indication for UKA. Further research is required to understand if these MRI changes will affect long-term outcomes.

Patient Factors Influencing Outcomes at 12-Year Follow-up of Hip Arthroscopy for Femoroacetabular Impingement

Background: Arthroscopic treatment of femoroacetabular impingement has increased in popularity since the early 2000s when it was first described, although only a few midterm follow-up studies have been published. Purpose: To describe the outcomes of patients undergoing hip arthroscopy for femoroacetabular impingement at a mean 12-year follow-up and to determine the risk factors for failure. Study Design: Case-control study; Level of evidence, 3. Methods: The Non-Arthritic Hip Score (NAHS) and a radiographic evaluation were completed preoperatively and at midterm follow-up. Participants were divided into 2 groups according to their clinical evolution. The success group consisted of patients whose NAHS at the final follow-up was above the established Patient Acceptable Symptom State (PASS) threshold of 81.9, whereas patients who underwent a second surgical intervention or did not reach the PASS threshold at final follow-up were assigned to the failure group. These groups were compared to identify preoperative differences in demographic, pathological, and surgical factors. Results: A total of 95 hips were included, after 23 were lost to follow-up (80.5% follow-up). At a mean follow-up of 12.1 years (range, 9.2-16.0 years), 9 hips required total hip arthroplasty (9.5%), 5 required revision hip arthroscopy (5.3%), 29 did not achieve the NAHS PASS threshold (30.5%), and 52 achieved the NAHS PASS threshold (54.7%). The mean NAHS was 82.4 at final follow-up compared with 66.9 preoperatively (mean difference = 15.5; P < .001). Higher mean body mass index (24.9 vs 23.0; P = .030), older age (30.0 vs 27.2; P = .035), and inferior preoperative lateral joint space width (3.9 vs 4.4; P = .019) were associated with inferior prognosis in the failure group versus success group. Osteoarthritis progression was observed in 69.2% of the failure group and in 34.8% of the success group (P = .082). Labral ossification was observed in 78.3% of all patients, and its lateral projection length was statistically associated with failure (P = .015). Conclusion: At a mean 12-year follow-up, hip arthroscopy for femoroacetabular impingement led to significant clinical improvement, with 55% PASS achievement. In total, 31% of patients were below the PASS threshold, 5% had revision arthroscopy, and only 9% had conversion to total hip arthroplasty for a 45% global failure rate. Increased body mass index, older age, and smaller preoperative lateral joint space width were significant negative prognostic factors. Postoperative degenerative changes were highly prevalent and demonstrated association with failure.