Sarcopenia: an unsolved problem after hip fracture.

INTRODUCTION: Sarcopenia, loss of muscle mass and strength, leads to functional dependence and disability. To date, no study reported the postoperative change of sarcopenia prevalence after hip fractures. Thus, we assessed postoperative changes in the prevalence of osteoporosis and sarcopenia in hip fracture patients. MATERIALS AND METHODS: Among 1159 patients, who underwent surgery for low-energy hip fractures between May 2012 and December 2019, 224 patients (38 men and 186 women with a mean age of 76.8 ± 8.7 years) were studied with preoperative and follow-up dual-energy X-ray absorptiometry (DXA). Bone mineral density (BMD) and skeletal muscle mass were measured on DXA scans. The postoperative changes in the prevalence of osteoporosis and that of the sarcopenia were evaluated as well as Koval grade of the hip fracture patients. RESULTS: While there was no significant change in BMD, SMI significantly decreased postoperatively. Mean decrease of the SMI was 0.53 kg/m2 in men and 0.38 kg/m2 in women. Prevalence of sarcopenia increased from 63 to 89% (p = 0.014) in men and from 45 to 57% (p = 0.006) in women. Lower BMI (Odds ratio (OR) 0.85 (95% confidence interval (CI) 0.76-0.96), p = 0.008) and prior sarcopenia (OR 14.47 (95% CI 5.29-35.39), p < 0.001) were the risk factors for the decrease of SMI after hip fracture. CONCLUSIONS: After hip fracture, osteoporosis seemed to be well managed and the prevalence of osteoporosis did not increase. However, SMI decreased and the prevalence of sarcopenia increased. More active measures are warranted to prevent sarcopenia in elderly hip fracture patients.

Positivity of Rapid Antigen Testing for SARS-CoV-2 With Serial Followed-up Nasopharyngeal Swabs in Hospitalized Patients due to COVID-19.

Despite the accuracy of nucleic acid amplification tests (NAATs), rapid antigen tests (RATs) for severe acute respiratory syndrome coronavirus-2 are widely used as point-of-care tests. A total of 282 pairs of reverse transcription-polymerase chain reaction and Standard Q COVID-19 Ag tests were serially conducted for 68 patients every 3-4 days until their discharge. Through a field evaluation of RATs using direct nasopharyngeal swabs, the sensitivities were 84.6% and 87.3% for E and RNA-dependent RNA polymerase (RdRp) genes, respectively, for specimens with cycle thresholds (Cts) < 25. The Ct values of E and RdRp genes for 95% detection rates by RATs were 16.9 and 18.1, respectively. The sensitivity of RAT was 48.4% after the onset of symptoms, which was not sufficient. RAT positivity gradually decreased with increased time after symptom onset and had continuously lower sensitivity than NAATs.

Toll-like Receptor Signaling Inhibitory Peptide Improves Inflammation in Animal Model and Human Systemic Lupus Erythematosus.

Toll-like receptors (TLRs) play a major role in the innate immune system. Several studies have shown the regulatory effects of TLR-mediated pathways on immune and inflammatory diseases. Dysregulated functions of TLRs within the endosomal compartment, including TLR7/9 trafficking, may cause systemic lupus erythematosus (SLE). TLR signaling pathways are fine-tuned by Toll/interleukin-1 receptor (TIR) domain-containing adapters, leading to interferon (IFN)-α production. This study describes a TLR inhibitor peptide 1 (TIP1) that primarily suppresses the downstream signaling mediated by TIR domain-containing adapters in an animal model of lupus and patients with SLE. The expression of most downstream proteins of the TLR7/9/myeloid differentiation factor 88 (MyD88)/IFN regulatory factor 7 signaling was downregulated in major tissues such as the kidney, spleen, and lymph nodes of treated mice. Furthermore, the pathological analysis of the kidney tissue confirmed that TIP1 could improve inflammation in MRL/lpr mice. TIP1 treatment downregulated many downstream proteins associated with TLR signaling, such as MyD88, interleukin-1 receptor-associated kinase, tumor necrosis factor receptor-associated factor 6, and IFN-α, in the peripheral blood mononuclear cells of patients with SLE. In conclusion, our data suggest that TIP1 can serve as a potential candidate for the treatment of SLE.

Risk factors for hardware-related complications after extra-articular distal humerus fracture fixation using an anatomical locking plate.

PURPOSE: We aimed to identify the incidence and risk factors of hardware-related complications in patients treated with anatomical locking plate fixation for extra-articular distal humerus fractures. METHODS: From 2013 to 2020, patients with extra-articular distal humerus fractures who underwent open reduction and internal fixation with an extra-articular distal humerus locking plate (EADHP) were retrospectively reviewed and categorized according to the presence/absence of hardware-related complications. Hardware-related complications were defined as the occurrence of skin prominence on the plate and discomfort in activities of daily living. Patient demographics, the lateral condylar angle, lateral body length, shaft-condylar angle of the humerus, and plate length were analyzed. RESULTS: Of the 29 patients, 10 (34%) did not develop hardware-related complications (group A), whereas 19 (66%) did (group B). Patient demographics did not differ between the groups. However, the number of patients who underwent hardware removal was significantly greater in group B (16/19) than in group A (4/10; p = 0.032). Radiologic assessment revealed no significant difference in the lateral condylar or shaft-condylar angle. However, the lateral body length was greater in group A than in group B (44.5 ± 4.8 vs. 39.5 ± 3.7, p = 0.007). The plate length significantly differed between the groups. Twelve of 19 (63%) patients in group B received short-hole plates (six holes), while nine of ten (90%) patients in group A received long-hole plates (eight holes). In the multivariable analysis, the lateral body length of the distal humerus (p = 0.047, odds ratio = 0.734, 95% confidence interval: 0.542-0.996) and plate length (p = 0.036, odds ratio = 0.076, 95% confidence interval: 0.542-0.996) were associated with hardware-related complications. CONCLUSIONS: Most patients developed hardware-related complications, particularly with short plates, mainly because of the narrow lateral body length of the distal humerus. Surgeons should be careful to secure EADHP in the appropriate position, especially when short plates are used in patients with narrow lateral body length.

Measurement of interspinous motion in dynamic cervical radiographs using a deep learning-based segmentation model.

OBJECTIVE: Interspinous motion (ISM) is a representative method for evaluating the functional fusion status following anterior cervical discectomy and fusion (ACDF) surgery, but the associated measuring difficulty and potential errors in the clinical setting remain concerns. The aim of this study was to investigate the feasibility of a deep learning-based segmentation model for measuring ISM in patients who underwent ACDF surgery. METHODS: This study is a retrospective analysis of flexion-extension dynamic cervical radiographs from a single institution and a validation of a convolutional neural network (CNN)-based artificial intelligence (AI) algorithm for measuring ISM. Data from 150 lateral cervical radiographs from the normal adult population were used to train the AI algorithm. A total of 106 pairs of dynamic flexion-extension radiographs from patients who underwent ACDF at a single institution were analyzed and validated for measuring ISM. To evaluate the agreement power between human experts and the AI algorithm, the authors assessed the interrater reliability using the intraclass correlation coefficient and root mean square error (RMSE) and performed a Bland-Altman plot analysis. They processed 106 pairs of radiographs from ACDF patients into the AI algorithm for autosegmenting the spinous process created using 150 normal population radiographs. The algorithm automatically segmented the spinous process and converted it to a binary large object (BLOB) image. The rightmost coordinate value of each spinous process from the BLOB image was extracted, and the pixel distance between the upper and lower spinous process coordinate value was calculated. The AI-measured ISM was calculated by multiplying the pixel distance by the pixel spacing value included in the DICOM tag of each radiograph. RESULTS: The AI algorithm showed a favorable prediction power for detecting spinous processes with an accuracy of 99.2% in the test set radiographs. The interrater reliability between the human and AI algorithm of ISM was 0.88 (95% CI 0.83-0.91), and its RMSE was 0.68. In the Bland-Altman plot analysis, the 95% limit of interrater differences ranged from 0.11 to 1.36 mm, and a few observations were outside the 95% limit. The mean difference between observers was 0.02 ± 0.68 mm. CONCLUSIONS: This novel CNN-based autosegmentation algorithm for measuring ISM in dynamic cervical radiographs showed strong agreement power to expert human raters and could help clinicians to evaluate segmental motion following ACDF surgery in clinical settings.

Osteoporotic Fractures among Selective Estrogen Receptor Modulator Users in South Korea: Analysis Using National Claims Database.

BACKGROUND: We evaluated (1) compliance with selective estrogen receptor modulator (SERM) use in postmenopausal women; and (2) the risk of osteoporotic fractures according to compliance and other patient characteristics. METHODS: National claims data of postmenopausal women from January 2013 to December 2014 were reviewed. Demographics, comorbidities, type of medical institution, and patient compliance were investigated. Compliance was measured according to medication possession ratio (MPR) and the patients were classified into compliant (MPR ≥80%) or non-compliant (MPR <80%) groups. Osteoporotic fractures were followed up for 2 years after prescription. RESULTS: Among 15,166 postmenopausal women, 4,130 were categorized as compliant. Osteoporotic fractures were confirmed in 669 patients. The hip fracture rate in the non-compliant group (0.39%) was marginally higher than that in the compliant group (0.36%; P=0.06). Compared to age 50 to 54 years, age 55 to 59 years showed protection against fractures (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.379-0.857; P=0.007), while those over 70 years showed a higher risk of fractures (HR, 2.035; 95% CI, 1.485-2.789; P<0.0001 for age 70-74 years; HR, 2.197; 94% CI, 1.588-3.041; P<0.0001 for age 75-79 years; and HR, 3.53; 95% CI, 2.493-4.999; P<0.0001 for age ≥80 years). Patients with mild (HR, 1.29; 95% CI, 1.088-1.530; P=0.0034) and moderate (HR, 1.286; 95% CI, 1.002-1.652; P=0.0486) comorbidities were associated with higher risks of fractures compared to those without comorbidities. CONCLUSIONS: Among postmenopausal women with osteoporosis, only 27.2% complied with SERM therapy. A marginal difference in hip fracture rate was observed between the compliant and non-compliant groups. Older age and severe comorbidities were associated with higher risks of osteoporotic fractures.

Prevalence of sarcopenia and mortality rate in older adults with hip fracture.

BACKGROUND: Several international study groups adopted appendicular skeletal muscle mass (ASM) index adjusted by (1) height squared, (2) weight, and (3) body mass index (BMI) in the diagnosis of sarcopenia. However, different prevalence rates of sarcopenia by each index and clinical implications were not well known. The purpose of this study was to compare the differences in (1) the percentage of sarcopenia in hip fracture patients and (2) the relative mortality rate according to the sarcopenia criteria of three ASM indices. METHODS: Between January 2009 and December 2020, 1003 older adult hip fracture patients at a tertiary institution were eligible and retrospectively reviewed for this study. Based on the ASM measured on dual-energy X-ray absorptiometry, three indices were calculated, and sarcopenia was diagnosed. The proportion of sarcopenia was evaluated according to each index. One, two, and five-year mortality rates were compared between each sarcopenia group and a normal musculature group, based on ASM criteria. RESULTS: The proportion of sarcopenia patients differed according to three ASM indices. The proportion of sarcopenic patients by ASM/height2 index was higher than those of the other two indices in both male and female hip fracture patients. In male patients, 61% were sarcopenic by ASM/height2 index, 37% by ASM/weight index, and 44% by ASM/BMI index. In female patients, 26%, 11%, and 14% were sarcopenic, respectively. Among the three indices, only ASM/height2 had significant correlations with all 1-, 2-, and 5-year mortality rates. CONCLUSIONS AND IMPLICATIONS: The prevalence of sarcopenia in hip fracture patients differed substantially according to ASM indices. Sarcopenic hip fracture patients had a higher mortality rate than those with normal musculature. The 1-year, 2-year, and 5-year mortality rates were discriminated by ASM/height2 criteria in both men and women. Future prospective studies in a larger cohort are warranted.