Faculty Bibliography

Background: Literature on glenohumeral dislocations has focused on younger patient populations due to high recurrence rates. However, the spectrum of injuries sustained in younger versus older patient populations is reported to be quite different. Objective: To describe MRI findings and management of anterior shoulder instability in the aging (≥60 years) population. Methods: Shoulder MRIs of anterior glenohumeral dislocators aged ≥40 were subdivided into <60 or ≥60 age groups, and reviewed by two musculoskeletal radiologists for: Hill-Sachs lesion, other fracture, glenoid injury, capsulolabral injury, rotator cuff tear, muscle atrophy, and axillary nerve injury. Fischer exact and logistic regression evaluated for significant differences between cohorts, and inter-reader agreement was assessed. Surgical management was recorded, if available. Results: 104 shoulder MRIs (40-79 years, mean=58.3, 52 females, 52 males) were reviewed (N=54 age <60, N=50 age ≥60). Acute high-grade or full-thickness supraspinatus (64.0% vs. 37.0%, p=0.001), infraspinatus (28.0% vs. 14.8%, p=0.028), and subscapularis tears (22.0% vs. 3.7%, p=0.003) were more common in the ≥60 group. Hill-Sachs lesions were more common in the <60 group (81.5% vs. 62.0%, p=0.046). Greater tuberosity fractures were seen in 15.3% of the overall cohort, coracoid fractures in 4.8%, and axillary nerve injuries in 16.3%. Inter-reader concordance was 88.5-89.4% for rotator cuff tears, and 89.4-97.1% for osseous injury. The <60 group had rotator cuff repair in 11/37 subjects (29.7%), and labral repair in 11/37 (29.7%), while the ≥60 group underwent rotator cuff repair in 17/36 (47.2%), reverse shoulder arthroplasty in 6/36 (16.7%), and labral repair in 6/36 (16.7%). Conclusion: Radiologists should have a high index of suspicion for acute rotator cuff tears in anterior shoulder instability, especially in aging populations. Greater tuberosity or coracoid fractures and axillary nerve injury occur across all ages, while Hill-Sachs injuries are more common in younger patients. Clinical Impact: Acute, high-grade or full-thickness rotator cuff tears are seen with higher frequency in older populations after anterior glenohumeral dislocation in the elderly. Osseous and nerve injuries are important causes of patient morbidity that, if not carefully sought out, may be overlooked by the interpreting radiologist on routine imaging.

OBJECTIVE:The purpose of this study was to determine the cost-effectiveness of landmark-based and image-guided intraarticular steroid injections for the initial treatment of a population with adhesive capsulitis. MATERIALS AND METHODS/METHODS:A decision analytic model from the health care system perspective over a 6-month time frame for 50-year-old patients with clinical findings consistent with adhesive capsulitis was used to evaluate the incremental cost-effectiveness of three techniques for administering intraarticular steroid to the glenohumeral joint: landmark based (also called blind), ultrasound guided, and fluoroscopy guided. Input data on cost, probability, and utility estimates were obtained through a comprehensive literature search and from expert opinion. The primary effectiveness outcome was quality-adjusted life years (QALY). Costs were estimated in 2017 U.S. dollars. RESULTS:Ultrasound-guided injections were the dominant strategy for the base case, because it was the least expensive ($1280) and most effective (0.4096 QALY) strategy of the three options overall. The model was sensitive to the probabilities of getting the steroid into the joint by means of blind, ultrasound-guided, and fluoroscopy-guided techniques and to the costs of the ultrasound-guided and blind techniques. Two-way sensitivity analyses showed that ultrasound-guided injections were favored over blind and fluoroscopy-guided injections over a range of reasonable probabilities and costs. Probabilistic sensitivity analysis showed that ultrasound-guided injections were cost-effective in 44% of simulations, compared with 34% for blind injections and 22% for fluoroscopy-guided injections and over a wide range of willingness-to-pay thresholds. CONCLUSION/CONCLUSIONS:Ultrasound-guided injections are the most cost-effective option for the initial steroid-based treatment of patients with adhesive capsulitis. Blind and fluoroscopy-guided injections can also be cost-effective when performed by a clinician likely to accurately administer the medication into the correct location.

Fluorodeoxyglucose (FDG) positron emission tomography-magnetic resonance (PET/MR) is useful for the evaluation of cognitively-impaired patients. This study aims to assess two different attenuation correction (AC) methods (Dixon-MR and atlas-based) versus index-standard computed tomography (CT) AC for the visual interpretation of regional hypometabolism in patients with cognitive impairment. Two board-certified nuclear medicine physicians blindly scored brain region FDG hypometabolism as normal versus hypometabolic using two-dimensional (2D) and 3D FDG PET/MR images generated by MIM software. Regions were quantitatively assessed as normal versus mildly, moderately, or severely hypometabolic. Hypometabolism scores obtained using the different methods of AC were compared, and interreader, as well as intra-reader agreement, was assessed. Regional hypometabolism versus normal metabolism was correctly classified in 16 patients on atlas-based and Dixon-based AC map PET reconstructions (vs. CT reference AC) for 94% (90%-96% confidence interval [CI]) and 93% (89%-96% CI) of scored regions, respectively. The averaged sensitivity/specificity for detection of any regional hypometabolism was 95%/94% (P = 0.669) and 90%/91% (P = 0.937) for atlas-based and Dixon-based AC maps. Interreader agreement for detection of regional hypometabolism was high, with similar outcome assessments when using atlas- and Dixon-corrected PET data in 93% (Κ =0.82) and 93% (Κ =0.84) of regions, respectively. Intrareader agreement for detection of regional hypometabolism was high, with concordant outcome assessments when using atlas- and Dixon-corrected data in 93%/92% (Κ =0.79) and 92/93% (Κ =0.78). Despite the quantitative advantages of atlas-based AC in brain PET/MR, routine clinical Dixon AC yields comparable visual ratings of regional hypometabolism in the evaluation of cognitively impaired patients undergoing brain PET/MR and is similar in performance to CT-based AC. Therefore, Dixon AC is acceptable for the routine clinical evaluation of dementia syndromes.