Beneficial effects of denosumab on muscle performance in patients with low BMD: a retrospective, propensity score-matched study.

This study examined the effects of denosumab compared to bisphosphonates and vitamin D alone on muscle performance in patients with low BMD. While grip force improved in both the denosumab and bisphosphonate group, a superior increase in chair rising test force was observed in the denosumab group. INTRODUCTION: The aim of this study was to investigate the effect of the anti-resorptive agent denosumab (Dmab) on upper and lower limb muscle performance compared to bisphosphonate (BP) treatment and vitamin D supplementation alone (i.e., basic therapy) in patients with low BMD. METHODS: This retrospective, propensity score-matched (sex, age, BMI, follow-up time) cohort study included 150 osteopenic or osteoporotic patients receiving basic (n = 60), BP (n = 30) or Dmab (n = 60) therapy. All patients underwent a musculoskeletal assessment at baseline and follow-up, including DXA, laboratory bone metabolism parameters, grip force, and chair rising test mechanography. Mean annual percentage changes were calculated and compared between study groups. RESULTS: After a mean follow-up period of 17.6 ± 9.0 months, a significantly higher increase in grip force in both the Dmab (p < 0.001) and BP group (p = 0.001) compared to the vitamin D group was observed (vitamin D = - 6.1 ± 10.2%; BP = + 0.8 ± 8.2%; Dmab = + 5.1 ± 25.5%). The Dmab group showed a significantly higher increase in chair rising test force compared to the BP group (vitamin D = + 5.8 ± 12.7%; BP = + 0.9 ± 8.6%; Dmab = + 8.2 ± 14.4%; Dmab vs. BP p = 0.03). Neither the changes in BMD nor in bone metabolic parameters were associated with changes in muscle performance. CONCLUSION: Dmab resulted in increased muscle strength in the upper and lower limbs, indicating systemic rather than site-specific effects as compared to BP. Based on these findings, Dmab might be favored over other osteoporosis treatments in patients with low BMD and poor muscle strength.

Evaluation of postural stability in patients screened for osteoporosis: A retrospective study of 1086 cases.

BACKGROUND: Although the interactions between balance, falls and fracture risk have been demonstrated in various aspects, the clinical focus of fracture risk evaluation has been on bone properties, e.g., bone mineral density (BMD). Accordingly, the role of balance parameters in the setting of osteoporosis assessment remained to be further explored. RESEARCH QUESTION: Is postural stability assessed by Romberg quiet stance posturography influenced by BMD or prior fragility fractures in a cohort of more than 1000 patients screened for osteoporosis? METHODS: Patients who completed both Romberg test and dual energy X-ray absorptiometry (DXA) were included retrospectively from a large database. Quantification of the Romberg test was performed by using posturography. Center of pressure (CoP) movements were tracked and the corresponding path length for ten seconds as well as an ellipse area including 90 % of all CoP were calculated. To determine potential predictors of posturography, simple and multiple linear regression analyses were performed including DXA results, grip strength, age, sex and BMI. As a secondary outcome, the influence of a previous fragility fracture on postural stability was evaluated. RESULTS: Overall, 1086 patients (801 women, 285 men) met the inclusion criteria. Lower femoral BMD T-score (p < 0.05), higher age (p < 0.001) and male sex (p < 0.001) were associated with higher Romberg path length (both eyes open and eyes closed). Both women and men with any previous fragility fracture showed significantly increased values in the path length with eyes open (p < 0.05) and eyes closed (women p < 0.001, men p < 0.05) compared to those without a history of a fragility fracture. SIGNIFICANCE: Our study indicates that postural stability is affected by femoral BMD, age and sex. As a history of prior fragility fracture was associated with postural instability, assessment and management of impaired balance in everyday clinical practice is advisable for optimal fracture prevention.

Diagnostic yield of cone beam computed tomography for small foreign body detection in the hand in comparison with radiography, MSCT and MRI: an ex vivo study.

INTRODUCTION: Detection of symptomatic foreign bodies (FB) after penetrating hand injuries can be challenging. Multiplanar radiography is most frequently used for FB detection and may be complemented by multislice computed tomography (MSCT) if suspected FBs cannot be identified and clinical symptoms are persisting. Cone beam computed tomography (CBCT) is a promising imaging modality for traumatology aside from fracture detection. The aim of this study was to evaluate the diagnostic yield of CBCT for different small FBs in the hand in comparison with radiography, MSCT and magnetic resonance imaging (MRI). METHODS: In ten cadaveric hands of voluntary body donors, 20 different FBs (metal, glass, stone, wood, thorn) in predefined sizes (0.5, 1 and 2mm) were randomly placed in the central hand and the basal phalanges. All hands were imaged using radiography, 256-slice CT, CBCT, and 3T MRI. A total of 200 subcutaneous and intramuscular particles were analyzed for their visibility by two observers at two time points. The Cohens Kappa coefficient was calculated as a measure of interobserver agreement and intraobserver reliability. The particle detection rate between different imaging modalities was compared using McNemar Chi2-tests. RESULTS: CBCT and MSCT provided a higher detection rate (94.6% and 86.3%) for detecting metal, glass and stone particles compared to standard radiography (70.0%; each p<0.001). MRI did not provide a diagnostic benefit. Wood particles and thorns were not reliably recognizable by any imaging technique. The interobserver agreement (K=0.768; p<0.001) and the intraobserver reliability for both observers (K1=0.914 and K2=0.907; p<0.001) were good. The dose length product (DLP) was 2-fold lower in CBCT than in MSCT (39.2 ± 2.1 vs. 81.4 ± 2.9 mGy*cm; p<0.001). CONCLUSIONS: In this ex vivo study, CBCT provided a high detection rate for small metal, glass, and stone particles while the radiation exposure was significantly lower compared to MSCT. These results suggest that CBCT instead of MSCT seems a reasonable option in supplementary diagnostics to exclude of FBs. The primary use of CBCT instead of radiography may be considered for symptomatic patients with expected small radiopaque particles <1mm. Organic FBs can be visualized indirectly in MRI and CBCT/MSCT by entrapped surrounding air. LEVEL OF EVIDENCE: Level I, diagnostic study.

Low physical performance determined by chair rising test muscle mechanography is associated with prevalent fragility fractures.

This study examined associations between physical performance assessed by chair rising test muscle mechanography and DXA T-score as well as body composition in a large patient cohort. Next to various significant interrelationships between these muscle and bone parameters, lower physical performance was associated with prevalent fragility fractures. PURPOSE: Although the interaction between muscle and bone has been demonstrated in various aspects, the clinical focus in the diagnosis of musculoskeletal disorders mainly lies on the skeletal assessments. Accordingly, the association between muscle function, bone mineral density (BMD), and fragility fractures remains to be further elucidated with a feasible muscle assessment in a clinical setting. METHODS: Patient data (2076 patients, 1538 women, 538 men) were evaluated retrospectively from a large dual energy X-ray absorptiometry (DXA) database as well as from chair rising test (CRT) that was performed on a muscle mechanograph. To determine potential predictors of the CRT time and maximum force, a multivariate regression analysis was performed including age, DXA T-score, and body composition indices. Furthermore, CRT results were compared between non-fracture and fracture cases. RESULTS: We determined independent predictors for CRT time such as age, femoral DXA T-score, and total fat mass, whereas CRT force was only influenced by total lean mass. Both women and men with previous fragility fractures displayed a longer CRT time (women p = 0.009, men p = 0.001) and lower CRT force (women p < 0.001, men p < 0.001) than those with no fractures, while no clear differences in CRT results could be detected between normal BMD, osteopenia, and osteoporosis based on DXA T-scores. CONCLUSIONS: Our study demonstrates that in addition to the associations between chair rising time and femoral T-score assessed by DXA, low muscle strength is associated with previous fragility fractures.