Heterotopic ossification (HO) is a debilitating pathology where ectopic bone develops in areas of soft tissue. HO can develop as a consequence of traumatic insult or as a result of dysregulated osteogenic signaling, as in the case of the orphan disease fibrodysplasia ossificans progressiva (FOP). Traumatic HO (tHO) formation is mediated by the complex interplay of signaling between progenitor, inflammatory, and nerve cells, among others, making it a challenging process to understand. Research into the pathogenesis of genetically mediated HO (gHO) in FOP has established a pathway involving uninhibited activin-like kinase 2 receptor (ALK2) signaling that leads to downstream osteogenesis. Current methods of diagnosis and treatment lag behind pre-mature HO detection and progressive HO accumulation, resulting in irreversible decreases in range of motion and chronic pain for patients. As such, it is necessary to draw on advancements made in the study of tHO and gHO to better diagnose, comprehend, prevent, and treat both.

Fatty infiltration of the rotator cuff muscles is very common following rotator cuff tears and is one of the most important factors in determining treatment. Current clinical practice relies on subjective evaluation of fatty infiltration through categorical scoring based on the Goutallier classification system. The Dixon magnetic resonance imaging (MRI) sequence provides flexibility in selecting echo times for water–fat separation. The Dixon method, therefore, has the potential to provide robust and high-quality fat quantification that allows for more accurate calculation of fat fraction (%Fat) of the rotator cuff muscles than the Goutallier classification system. However, significant variance exists in sequencing and post-processing methodology within the recent application of Dixon sequences to quantify rotator cuff fatty infiltration. In this paper, we conducted a systematic review to synthesize the relevant literature utilizing Dixon sequencing for the quantification of rotator cuff fatty infiltration. The literature search was extracted from 1094 articles, with 12 studies included in the final review. Regardless of the varying sequencing pattern and post-processing techniques among studies, the findings suggest the Dixon method is reliable for quantitatively calculating the fat fraction of the rotator cuff muscles, even at very low levels of fatty infiltration. In addition, a quantitative difference in fat fraction was observed between participants with different degrees of tear vs. those without any shoulder pathologies. Multi-point Dixon imaging has the potential to be utilized clinically to objectively quantify fatty infiltration and may lead to improved clinical decision making for patients with rotator cuff tears.

Rotator cuff myosteatosis following cuff tears is very common and one of the most important prognostic factors in clinical management. Quantitative ultrasound-based imaging techniques (QUBIT) are frequently used along with magnetic resonance imaging (MRI) to evaluate rotator cuff fatty degeneration. However, the examination of rotator cuff tissue integrity by QUBIT is lacking a standardized imaging protocol and procedural methodologies. In this scoping review, we synthesized the current state of QUBIT against the reference imaging modalities in patients with rotator cuff tears. The literature search was extracted from 963 studies, with 22 studies included in the final review in accordance with the preferred reporting items for systematic reviews and meta-analyses extensions for scoping reviews. The selected studies included human participants and focused on measuring at least one prognostic or diagnostic factor using ultrasonography-based imaging with reference to MRI. The findings suggest both conventional B-mode ultrasound and shear wave elastography imaging were comparable to MRI-based imaging techniques for the evaluation of fatty infiltration and rotator cuff tear characterization. This review establishes guidelines for reporting shoulder-specific QUBIT aimed at developing a standardized imaging protocol. The objective was to enhance the diagnostic and prognostic capabilities of QUBIT in the clinical setting.

Background: Total hip arthroplasty (THA) has become a growing treatment procedure for debilitating hip pathologies. Patients experienced post-operative complications and revision surgeries according to large THA registries. To fully understand the short-term and long-term post-operative outcomes following THA, the purpose of this study is to examine the incidence of post-operative complications following primary THA and to examine how this trend has changed over 10 years within community hospitals in the US using large databases. Methods: This study queried the State Inpatient Database (SID) for primary THA between 2006 and 2015. Individual patients were followed forward in time until the first instance of a post-operative complication. The multivariable logistic regression analyses were computed to examine which post-operative complications were independent predictors of pre-operative comorbidities. Results: Median age of patients was 67 years, and 56% of patients were female. Females with avascular necrosis (AVN) as an indication for THA had a 27% higher risk of complication. Females with osteoarthritis (OA) as an indication for THA had a 6% higher risk of complication. Post-operative complications occurred with higher frequencies in the first two months of THA and the highest risks of THA complications within the first 6 months. Conclusion: The most common indication is OA in elders with primary THA. Females and those of black ethnicity showed the greatest risks of THA complications. Data from our large study can be used to understand post-operative complications and readmissions after THA. Our study also provides data on risk factors associated with these complications.

Impaired shoulder function hinders the ability of wheelchair users to maintain independence. The current state of the literature delineates the risks and benefits of surgical techniques for the management of shoulder pathologies. To the best of our knowledge, there is no study that has investigated complications following total shoulder arthroplasty (TSA) in wheelchair users. Utilizing the PearlDiver Mariner national administrative database, 72,108 patients were identified who underwent TSA with a concurrent diagnosis of a rotator cuff tear. Two matched cohorts, one of wheelchair users and one of non-wheelchair users, were created. Due to limitations within PearlDiver, one-year outcomes, including comorbidity and complication rates and readmission statistics, were compared between the two cohorts. Each matched cohort of 869 patients underwent TSA with a concurrent diagnosis of a rotator cuff tear. The rate of readmission in wheelchair users was greater than in non-wheelchair users (24.05% vs. 9.55%, OR: 3.00, CI: 2.279, 3.946). Patients in the wheelchair cohort exhibited higher rates of complications and comorbidities (p < 0.001). Among the most likely to be readmitted after TSA were patients with osteoarthritis, pulmonary heart disease, rheumatoid arthritis, and hypertension (p < 0.05). Significant differences in surgical outcomes existed between wheelchair and non-wheelchair users in terms of preoperative comorbidities, postoperative complications, and readmission rates.

Background: Shoulder ultrasound is a well-established point-of-care diagnostic modality in orthopaedic and sports medicine. Despite offering measurements of high-quality morphology, this methodology has faced several challenges, including variability in ultrasound systems, operator dependency, and lack of reliable and objective quantitative measures to track disease progression and responses to therapeutic interventions. Computer-aided quantitative ultrasound algorithm (CAQUSA) is an emerging novelty that automates the detection of normal and abnormal structures. Although CAQUSA has been shown to improve detections and diagnoses of soft tissue lesions, the proof-of-concept of utilizing CAQUSA to measure subacromial space width and its encroachment to the rotator cuff tendon have not been tested to assist in clinical decision-making for subacromial pain syndrome.Objective: This study aimed to develop a CAQUSA that measured the acromiohumeral distance (AHD) and test the algorithm’s reliability and agreement with manual measurements in wheelchair users with spinal cord injury (SCI).Methods: 116 ultrasound video clips recorded from 10 manual wheelchair users with SCI were evaluated manually by an experienced examiner with expertise in AHD examination and by the CAQUSA, which was developed for bone segmentation with probability mapping. The reliability and agreement of the diagnostic performance between the examiner and the CAQUSA were calculated and compared in both groups of AHD measurements.Results: The CAQUSA achieved a satisfactory agreement between computer-aided (11.95 ± 2.29 mm) and manual (11.33 ± 2.48 mm) measurements. The intraclass correlation coefficient between the two measures was excellent (ICC = 0.95). The sensitivity was 0.2 mm, with 95% true positives and 5% false positives at the fixed threshold of CAQUSA.Conclusion: AHD measurements made by the clinical observer were similar to that of the CAQUSA for assessing the clinical metrics related to subacromial pain syndrome. However, the CAQUSA showed greater reliability in its unclear or misleading image analysis. Based on the findings of this proof-of-concept study, the CAQUSA has promise for clinical utilization and interchangeability to minimize examiner-dependent errors and potentially reduce the cost of care.