Pathoanatomy and pathomechanics of pertrochanteric fractures - an MRI study.

BACKGROUND AND STUDY AIMS: Magnetic resonance imaging (MRI) has been used for more than 20 years in the region of the proximal femur to diagnose occult, or incomplete, fractures of the femoral neck and the trochanteric segment. MRI has also potential to contribute to the understanding of the pathogenesis and pathoanatomy of trochanteric fractures. METHODS: The group including 13 patients was examined by MRI for a suspected, or incomplete, fracture of the trochanteric segment within 24 hours post-injury. In all cases, this was the first injury to the hip joint, with the other hip joint remaining intact. RESULTS: The coronal scans showed a marked fracture line which, in the region of the intertrochanteric line, extended from the base of the greater trochanter (GT) medially and distally and involved the medial cortex. This inclination, however, was gradually changing posteriorwards and close before the posterior cortex. The fracture line was passing vertically along the lateral trochanteric wall as far as the level of the lesser trochanter (LT). Then the fracture line changed its course and ran horizontally to the cortex of the LT. Sagittal scans showed clearly the primary fracture line originating in the greater trochanter, extending medially and starting to separate the posterior cortex. CONCLUSION: Analysis of MRI findings has documented that the primary fracture line in pertrochanteric fractures originates in the GT and extends distally, medially and anteriorly towards the anterior cortex, the intertrochanteric line and the LT. Thus, the GT presents a rather vulnerable site and is always broken into more fragments than shown by a radiograph.

Male-female spatio-temporal differences of age-related bone changes show faster bone deterioration in older women at femoral regions associated with incident hip fracture.

A better understanding of how age-related bone loss affects the fracture-prone regions of the proximal femur could lead to more informed fracture-prevention strategies. Therefore, the aim of this work was to assess the spatio-temporal distribution of bone deterioration in older men and women with aging. A subset of 305 men (74.87 ± 4.76 years; mean ± SD) and 371 age-matched women (74.84 ± 4.71 years) with no history of fracture was randomly selected from the Age, Gene/Environment Susceptibility-Reykjavik study. Quantitative computed tomography (QCT) scans of the left proximal femur obtained at baseline and at 5.2 ± 0.4 years follow-up were processed to assess local changes in volumetric bone mineral density (vBMD), cortical bone thickness (Ct.Th), and internal bone structure using voxel-based morphometry (VBM), surface-based statistical parametric mapping (surf-SPM), and tensor-based morphometry (TBM). Local parametric changes within each sex and sex differences in these changes were statistically assessed using linear mixed effects models allowing for baseline and time-varying covariates, yielding Student's t-test and p-value statistical maps of the proximal femur. The statistical maps indicated regions with significant parametric changes in each sex and with significant different parametric changes between older men and older women with aging. Older women manifested significantly larger losses in vBMD, (Ct.Th), and structure than older men, and they did so in regions where deficiency in these parameters has been associated with incident hip fracture. Using longitudinal QCT scans of the proximal femur and Computational Anatomy, we provided new insights into the higher fracture rates of the proximal femur in older women compared with men of similar age providing new information on the pathophysiology of osteoporosis.

Differences in Type 2 Fiber Composition in the Vastus Lateralis and Gluteus Maximus of Patients with Hip Fractures.

BACKGRUOUND: Aging leads to sarcopenia, which is characterized by reduced muscle mass and strength. Many factors, including altered muscle protein turnover, diminished neuromuscular function, hormonal changes, systemic inflammation, and the structure and composition of muscle fibers, play a crucial role in age-related muscle decline. This study explored differences in muscle fiber types contributing to overall muscle function decline in aging, focusing on individuals with hip fractures from falls. METHODS: A pilot study at Chungnam National University Hospital collected muscle biopsies from hip fracture patients aged 20 to 80 undergoing surgical treatment. Muscle biopsies from the vastus lateralis and gluteus maximus were obtained during hip arthroplasty or internal fixation. Handgrip strength, calf and thigh circumference, and bone mineral density were evaluated in individuals with hip fractures from falls. We analyzed the relationships between each clinical characteristic and muscle fiber type. RESULTS: In total, 26 participants (mean age 67.9 years, 69.2% male) were included in this study. The prevalence of sarcopenia was 53.8%, and that of femoral and lumbar osteoporosis was 19.2% and 11.5%, respectively. Vastus lateralis analysis revealed an age-related decrease in type IIx fibers, a higher proportion of type IIa fibers in women, and an association between handgrip strength and type IIx fibers in men. The gluteus maximus showed no significant correlations with clinical parameters. CONCLUSION: This study identified complex associations between age, sex, handgrip strength, and muscle fiber composition in hip fracture patients, offering insights crucial for targeted interventions combating age-related muscle decline and improving musculoskeletal health.

Acetabular dysplasia and posterior wall fractures: The missing link?

BACKGROUND: Traumatologists are unable to predict hip instability based on CT scans and standard radiographs in posterior wall (PW) fractures comprising <50-60 % of the wall, necessitating an examination under anesthesia (EUA). Risk factors for instability have not been clarified, but acetabular dysplasia has been theorized as a potential etiology. Unfortunately, dysplasia is difficult to evaluate in the traumatic setting. The purpose of this study was to compare acetabular morphology between unstable and stable fractures with a novel method to detect dysplasia. METHODS: Patients ≥ 18 years old with a PW fracture that underwent an EUA from 2013 to 2023 were retrospectively identified. For our experimental measurements, the axial distances on CT between the acetabular dome, lateral acetabular opening, and femoral head vertex were recorded. Acetabular geometry was quantified at these levels. Conventional dysplasia metrics (e.g., Tonnis angle) were obtained. Variables were compared between stable and unstable fractures. RESULTS: 58 patients met inclusion criteria with 42 stable versus 16 unstable fractures. Unstable fractures had higher distances between the acetabular dome and femoral head vertex (p > 0.05). They had more cranial fracture exit points (p = 0.0015), lower femoral head coverage (p = 0.0102), and lower posterior acetabular sector angles (p = 0.0281). No other differences in acetabular geometry, demographics, injury characteristics, or other markers of dysplasia were identified. CONCLUSIONS: Unstable hips demonstrated a more recessed acetabular dome when compared to stable hips. Posterior acetabular femoral head coverage and cranial fracture exit point may be related to hip instability. A larger sample size is needed to validate these findings.

Persistent Mesodermal Differentiation Capability of Bone Marrow MSCs Isolated from Aging Patients with Low-Energy Traumatic Hip Fracture and Osteoporosis: A Clinical Evidence.

A low-energy hit, such as a slight fall from a bed, results in a bone fracture, especially in the hip, which is a life-threatening risk for the older adult and a heavy burden for the social economy. Patients with low-energy traumatic bone fractures usually suffer a higher level of bony catabolism accompanied by osteoporosis. Bone marrow-derived stem cells (BMSCs) are critical in osteogenesis, leading to metabolic homeostasis in the healthy bony microenvironment. However, whether the BMSCs derived from the patients who suffered osteoporosis and low-energy traumatic hip fractures preserve a sustained mesodermal differentiation capability, especially in osteogenesis, is yet to be explored in a clinical setting. Therefore, we aimed to collect BMSCs from clinical hip fracture patients with osteoporosis, followed by osteogenic differentiation comparison with BMSCs from healthy young donors. The CD markers identification, cytokines examination, and adipogenic differentiation were also evaluated. The data reveal that BMSCs collected from elderly osteoporotic patients secreted approximately 122.8 pg/mL interleukin 6 (IL-6) and 180.6 pg/mL vascular endothelial growth factor (VEGF), but no PDGF-BB, IL-1b, TGF-b1, IGF-1, or TNF-α secretion. The CD markers and osteogenic and adipogenic differentiation capability in BMSCs from these elderly osteoporotic patients and healthy young donors are equivalent and compliant with the standards defined by the International Society of Cell Therapy (ISCT). Collectively, our data suggest that the elderly osteoporotic patients-derived BMSCs hold equivalent differentiation and proliferation capability and intact surface markers identical to BMSCs collected from healthy youth and are available for clinical cell therapy.

Neoplastic pathologic hip fractures are associated with a higher risk of post-operative bleeding and thromboembolic events.

INTRODUCTION: Surgical treatment of hip fractures leads to significant post-operative complications. Although pathologic fractures (PF) are associated with worse outcomes, most studies do not differentiate between etiology (neoplastic and non-neoplastic PF). We seek to compare 30-day complication rates between 1) native hip fractures and neoplastic PF, and 2) neoplastic and non-neoplastic PF. MATERIALS AND METHODS: A total of 127,819 patients with hip fractures and 5104 with PF diagnosed from 2005 to 2021 were retrieved from the NSQIP database. We included 1843 patients with neoplastic PF and 3261 with non-neoplastic PF. Demographics, pre-operative labs and co-morbidities, and post-operative outcomes were analyzed. Propensity-score matching was conducted to control for confounders. RESULTS: Patients with a neoplastic PF had a significantly higher rate of deep venous thrombosis (DVT) (4 % vs 1.2 %, p = 0.001) and pulmonary embolism (PE) (2.4 % vs 0.7 %, p < 0.001), than native hip fractures. Rates of post-operative bleeding were significantly higher in the neoplastic PF group (29.3 % vs 23.9 %, p < 0.001) than non-neoplastic PF. No differences in soft tissue complications were found. When comparing neoplastic and non-neoplastic PF, the former had a higher rate of PE (2.5 % vs 1.0 %, p = 0.015) and post-operative bleeding (27.6 % vs 22.0 %, p = 0.009). Unplanned readmission rates and 30-day mortality rate were also higher in the neoplastic PF group. CONCLUSION: Neoplastic PF of the hip are associated with higher risk of thromboembolic event rates and post-operative bleeding than both native hip fractures and non-neoplastic PF. No differences in rates of soft tissue complications were found between groups.

Autophagy markers are decreased in bone of osteoporotic patients: a monocentric comparative study.

BACKGROUND: Osteoporosis (OP) is a pathology characterized by bone fragility affecting 30% of postmenopausal women, mainly due to estrogen deprivation and increased oxidative stress. An autophagy involvement is suspected in OP pathogenesis but a definitive proof in humans remains to be obtained. METHODS: Postmenopausal women hospitalized for femoral neck fracture (OP group) or total hip replacement (Control group) were enrolled using very strict exclusion criteria. Western blot was used to analyze autophagy level. RESULTS: The protein expression level of the autophagosome marker LC3-II was significantly decreased in bone of OP patients relative to the control group. In addition, the protein expression of the hormonally upregulated neu-associated kinase (HUNK), which is upregulated by female hormones and promotes autophagy, was also significantly reduced in bone of the OP group. CONCLUSIONS: These results demonstrate for the first time that postmenopausal OP patients have a deficit in bone autophagy level and suggest that HUNK could be the factor linking estrogen loss and autophagy decline. CLINICAL TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT03175874, 2/6/2017.

Epidemiology of proximal femur fractures in the young population of Qatar.

PURPOSE: To review the epidemiological characteristics of proximal femur fractures in the young population (< 60 years) of Qatar between 2017 and 2019. METHODS: All patient treated for proximal femur fractures at Hamad General Hospital (HGH), a level one trauma center, were retrospectively reviewed between Jan 2017 and Dec 2019. All adults (18-60 years) with proximal femur fracture (femur head, femur neck, intertrochanteric and subtrochanteric fractures) were included with no restriction to the AO/OTA classification or fractures subtypes. Excluded cases were pathological fractures, cases with insufficient documentation or no radiographs. RESULTS: A total of 203 patients with a mean age of 40.07 ± 11.76 years were included, of who 89.9% were males. The incidence of proximal femur fracture was 3.12/100,000/year. Fall from height (48.1%) followed by road traffic accidents (26.9%) were common cause of injury. The most common fracture type was intertrochanteric fracture (36.1%) followed by femur neck fractures (33.7%). CONCLUSION: This study provides the initial insights into the proximal femur fractures in the young population of Qatar. This is the first study to investigate of the epidemiology of such fractures in this particular patient group. Contrary to the existing literature on older age groups, the majority of the injuries were observed in males. Falls from height followed by road traffic accidents were the primary mechanisms leading to these fractures. Improved understanding of the profile of these injuries can aid in their prevention by implementing more effective safety measures.

The effect of pre-fracture proximal femur geometry on hip fracture type in elderly patients.

This study aimed to analyze the relationship between fracture type by determining data on the geometry of the proximal femur in the pre-fracture period in patients over 65 years of age who had hip fractures as a result of low-energy trauma. A total of 127 patients who were admitted to the hospital for reasons other than hip pathology within 1 year before the occurrence of hip fracture and who had an anterior-posterior pelvic X-ray were included in the study. Measurements were made to evaluate the proximal femur geometry, neck shaft angle, central edge angle, femoral head diameter, femoral neck diameter, femoral neck length, femoral offset length, femoral neck axial length, hip axis length, and femoral shaft diameter. As a result of these measurements, analyses were performed to determine the relationship between the control group and fracture types. The mean Neck shaft angle scores were significantly higher in both fracture types than in the control group (P = .034, P = .002). The mean Femoral offset length values of both fracture types were lower than those of the control group (P = .002, P = .011, respectively). Multiple logistic regression analysis revealed that the risk of collum femoris fracture increased as the Femoral head diameter value increased. (OD = 0.21, P = .002). The geometric parameters of the proximal femur play an important role in the formation of hip fracture types. Therefore, differences in proximal femur geometry in hip fracture types should be considered, and patient-focused choices should be made regarding the surgical procedures and implants to be used during fracture fixation.

Methyl-CpG binding protein 2 is associated with the prognosis and mortality of elderly patients with hip fractures.

OBJECTIVES: To investigate the expression level and clinical significance of Methyl-CpG binding Protein 2 (MECP2) in elderly patients with hip fractures. METHODS: This prospective observational study included 367 elderly patients with hip fractures between April 2016 and December 2018. All the patients were treated with internal fixation or joint replacement. In addition, 50 healthy elderly individuals were enrolled as healthy controls. The serum levels of MECP2 and inflammatory factors Interleukin (IL)-1ß, IL-6, IL-8, and Tumor Necrosis Factor (TNF)-α was determined by enzyme-linked immunosorbent assay. Data on patients' basic characteristics and postoperative complications were collected. The Harris score was used to assess hip function at 1-month, 3-months, and 6-months after surgery. Patient quality of life was measured using the Barthel Index (BI) score 3-months after surgery. The 1-year mortality was analyzed using the Kaplan-Meier curve, and logical regression was used to analyze the risk factors for mortality. RESULTS: No significant differences were observed in the basic clinical characteristics of all patients. The serum MECP2 levels were remarkably high in patients with hip fractures and negatively correlated with serum IL-1ß, IL-6, and TNF-α levels. Patients with higher MECP2 predicted higher dynamic Harris scores, lower postoperative complications, lower 1-year mortality, and higher BI scores. Logical regression showed that age was the only independent risk factor for postoperative 1-year mortality in elderly patients with hip fractures. CONCLUSION: Lower MECP2 predicted poor prognosis and higher 1-year mortality in elderly patients with hip fractures.

Dietary risk factors for hip fracture in adults: An umbrella review of meta-analyses of prospective cohort studies.

AIM: To summarise the totality of evidence regarding dietary risk factors for hip fracture in adults, evaluating the quality of evidence, to provide recommendations for practice and further research. DESIGN: Systematic review of meta-analyses of prospective cohort studies. ELIGIBILITY CRITERIA: Systematic reviews with meta-analyses reporting summary risk estimates for associations between hip fracture incidence and dietary exposures including oral intake of a food, food group, beverage, or nutrient, or adherence to dietary patterns. INFORMATION SOURCES: Medline, Embase, Web of Science, and the Cochrane Library from inception until November 2020. DATA SYNTHESIS: The methodological quality of systematic reviews and meta-analyses was assessed using AMSTAR-2, and the quality of evidence for each association was assessed using GRADE. Results were synthesised descriptively. RESULTS: Sixteen systematic reviews were identified, covering thirty-four exposures, including dietary patterns (n = 2 meta-analyses), foods, food groups, or beverages (n = 16), macronutrients (n = 3), and micronutrients (n = 13). Identified meta-analyses included 6,282 to 3,730,424 participants with between 322 and 26,168 hip fractures. The methodological quality (AMSTAR-2) of all systematic reviews was low or critically low. The quality of evidence (GRADE) was low for an inverse association between hip fracture incidence and intake of fruits and vegetables combined (adjusted summary relative risk for higher vs lower intakes: 0.92 [95% confidence interval: 0.87 to 0.98]), and very low for the remaining thirty-three exposures. CONCLUSION: Dietary factors may play a role in the primary prevention of hip fracture, but the methodological quality of systematic reviews and meta-analyses was below international standards, and there was a lack of high-quality evidence. More long-term cohort studies reporting absolute risks and robust, well-conducted meta-analyses with dose-response information are needed before policy guidelines can be formed. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42020226190.

Multiple screw fixation versus cementless bipolar hemiarthroplasty for femur neck fracture using a nationwide hip fracture registry.

Cementless bipolar hemiarthroplasty (BHA) recently gained popularity as a treatment for femur neck fracture (FNF), but there have been few studies comparing this with multiple screw fixation (MSF) in the elderly population. The purpose of this study is to compare (1) surgery-related parameters, (2) reoperation rate as a local complication, (3) in-hospital systemic complication rate, and (4) mortality rate at 1 year after MSF and cementless BHA in patients with FNF using nationwide data. Six-hundred sixty-six hips (aged ≥ 50 years) extracted from nationwide Hip Fracture Registry were included in this study (133 MSF and 533 cementless BHA). One hundred fifty-six hips were divided into nondisplaced FNF (Group A) and 510 into displaced FNF (Group B). We evaluated (1) surgery-related parameters (anesthesia type, time to surgery, operation time, estimated blood loss and volume of postoperative transfusion), (2) the rate of and reasons for reoperation, (3) the rate and type of in-hospital systemic complications and (4) one-year mortality rate after surgery. In Group A, MSF showed shorter operation time (p = 0.004) and lower incidence of in-hospital systemic complications (p = 0.003). In Group B, cementless BHA demonstrated lower reoperation rate than MSF (p < 0.001). In both Group A and B, cementless BHA was associated with higher estimated blood loss than MSF (p < 0.001). Based on findings in our study, MSF might be a more favorable option for nondisplaced FNF, whereas cementless BHA might be a better one for displaced FNF in patients older than fifty. Nevertheless, our nationwide study also showed that numbers of cementless BHAs were being performed for nondisplaced FNF even in teaching hospitals.

Population-based Analysis for Risk of Suicide Death in Elderly Patients after Osteoporotic Fracture: a Nested Case-Control Study.

BACKGROUND: The purpose of study was to investigate the incidence rate of suicide in elderly patients with osteoporotic fractures in a nested case-control model and to analyze the change in the risk of suicide death over time after each osteoporotic fracture. METHODS: We used the National Health Insurance Service-Senior cohort of South Korea. Suicide cases and controls were matched based on sex and age at the index date. Controls were randomly selected at a 1:5 ratio from the set of individuals who were at risk of becoming a case at the time when suicide cases were selected. Conditional logistic regression analysis was performed to evaluate the association between each type of osteoporotic fracture and the risk of suicide death. RESULTS: Three thousand seventy suicide cases and 15,350 controls were identified. Patients with hip fracture showed an increased risk of suicide death within 1 year of fracture (adjusted odds ratio [aOR] = 2.64; 95% confidence interval [CI], 1.57-4.46; P < 0.001) compared to controls. However, the increased risk of suicide death in patients with hip fracture lasted up to 2 years (aOR = 1.59; 95% CI, 1.04-2.41; P = 0.031). Spine fracture increased the risk of suicide deaths for all observation periods. There was no evidence that humerus fracture increased the risk of suicide death during the observational period. Radius fracture increased only the risk of suicide death within 2 years of fracture (aOR = 1.43; 95% CI, 0.74-2.77; P = 0.282). CONCLUSION: There were noticeable differences in both degree and duration of increased suicide risks depending on the type of osteoporotic fracture. Mental stress and suicide risk in elderly patients after osteoporotic fracture should be assessed differently depending on the types of fracture.

Transforming the German ICD-10 (ICD-10-GM) into Injury Severity Score (ISS)-Introducing a new method for automated re-coding.

BACKGROUND: While potentially timesaving, there is no program to automatically transform diagnosis codes of the ICD-10 German modification (ICD-10-GM) into the injury severity score (ISS). OBJECTIVE: To develop a mapping method from ICD-10-GM into ICD-10 clinical modification (ICD-10-CM) to calculate the abbreviated injury scale (AIS) and ISS of each patient using the ICDPIC-R and to compare the manually and automatically calculated scores. METHODS: Between January 2019 and June 2021, the most severe AIS of each body region and the ISS were manually calculated using medical documentation and radiology reports of all major trauma patients of a German level I trauma centre. The ICD-10-GM codes of these patients were exported from the electronic medical data system SAP, and a Java program was written to transform these into ICD-10-CM codes. Afterwards, the ICDPIC-R was used to automatically generate the most severe AIS of each body region and the ISS. The automatically and manually determined ISS and AIS scores were then tested for equivalence. RESULTS: Statistical analysis revealed that the manually and automatically calculated ISS were significantly equivalent over the entire patient cohort. Further sub-group analysis, however, showed that equivalence could only be demonstrated for patients with an ISS between 16 and 24. Likewise, the highest AIS scores of each body region were not equal in the manually and automatically calculated group. CONCLUSION: Though achieving mapping results highly comparable to previous mapping methods of ICD-10-CM diagnosis codes, it is not unrestrictedly possible to automatically calculate the AIS and ISS using ICD-10-GM codes.

Additional use of anti-rotation U-blade (RC) decreases lag screw sliding and limb length inequality in the treatment of intertrochanteric fractures.

The purpose of this study is to compare the cut-out rate and sliding distance associated with limb length inequality between operations using a standard non-sliding lag screw versus those using a non-sliding lag screw with U-blade (RC) in the Gamma3 nail. This is a retrospective review of two case series involving different lag screws for the Gamma3 nail. Propensity score matching analysis was used to adjust the confounding factors. A comparative analysis of 304 patients who treated with Gamma3 nail with either a standard non-sliding lag screw or a U-Blade (RC) lag screw was performed. Between 2014 and 2018, 152 patients were treated with U-blade (RC) lag screws, and these patients were matched with those treated with standard lag screws. There was no significant difference in cut-out rate between groups. However, additional use of anti-rotation U-blade (RC) could significantly decrease lag screw sliding, with the group treated with U-Blade (RC) lag screws exhibiting shorter sliding, especially in AO/OTA31 A2 and A3 fractures. Also, in A2 and A3 fractures, the mean lag screw sliding distance was greater than that seen in A1 fractures in both groups. These findings can help trauma surgeons choose the proper implant to reduce leg length inequality.

Risk factor analysis of fragility fractures in rheumatoid arthritis: A 3-year longitudinal, real-world, observational, cohort study.

OBJECTIVES: To explore the risk factors for fragility fractures in rheumatoid arthritis (RA) patients using a 3-year longitudinal, observational cohort study. METHODS: This RA registry study included consecutive RA patients in the outpatient clinic of Chang Gung Memorial Hospital since September 1, 2014. The demographics, clinical characteristics, lifestyle, evidence of previous fracture, risk factors according to the Fracture Risk Assessment Tool (FRAX®), and the FRAX score of each participant were recorded. The participants were categorized into the new incident fracture (group A) and no incident fracture (group B) groups based on evidence or absence of new incident fractures and propensity score matching (age and gender, 1:2). RESULTS: Overall, 477 participants completed the 3-year observation period. After matching, 103 and 206 participants were allocated to groups A and B, respectively. The non-adjusted model revealed, presented as hazard ratio (HR) (95% confidence interval [CI]), that the presence of co-morbidity (1.80 [1.17-2.78], p = 0.008), Health Assessment Questionnaire Disability Index (1.35 [1.07-1.69], p = 0.010), lower baseline hip bone mineral density (0.11 [0.02-0.48], p = 0.004), longer disease duration (1.02 [1.00-1.04], p = 0.026), higher FRAX score of major fracture (1.03 [1.02-1.04], p<0.001) or hip fracture (1.03 [1.02-1.04], p<0.001), and previous fracture history (2.65 [1.79-3.94], p<0.001) were associated with new incident fracture. After adjustment, it was disclosed that a previous fracture is an independent risk factor for fragility fractures in RA patients (2.17 [1.20-3.90], p = 0.010). CONCLUSIONS: In addition to aging and disease-related factors, previous fracture history is the most important risk factor for fragility fractures in RA patients.

A comparison of comorbidity measures for predicting mortality after elective hip and knee replacement: A cohort study of data from the National Joint Registry in England and Wales.

BACKGROUND: The risk of mortality following elective total hip (THR) and knee replacements (KR) may be influenced by patients' pre-existing comorbidities. There are a variety of scores derived from individual comorbidities that can be used in an attempt to quantify this. The aims of this study were to a) identify which comorbidity score best predicts risk of mortality within 90 days or b) determine which comorbidity score best predicts risk of mortality at other relevant timepoints (30, 45, 120 and 365 days). PATIENTS AND METHODS: We linked data from the National Joint Registry (NJR) on primary elective hip and knee replacements performed between 2011-2015 with pre-existing conditions recorded in the Hospital Episodes Statistics. We derived comorbidity scores (Charlson Comorbidity Index-CCI, Elixhauser, Hospital Frailty Risk Score-HFRS). We used binary logistic regression models of all-cause mortality within 90-days and within 30, 45, 120 and 365-days of the primary operation using, adjusted for age and gender. We compared the performance of these models in predicting all-cause mortality using the area under the Receiver-operator characteristics curve (AUROC) and the Index of Prediction Accuracy (IPA). RESULTS: We included 276,594 elective primary THRs and 338,287 elective primary KRs for any indication. Mortality within 90-days was 0.34% (N = 939) after THR and 0.26% (N = 865) after KR. The AUROC for the CCI and Elixhauser scores in models of mortality ranged from 0.78-0.81 after THR and KR, which slightly outperformed models with ASA grade (AUROC = 0.77-0.78). HFRS performed similarly to ASA grade (AUROC = 0.76-0.78). The inclusion of comorbidities prior to the primary operation offers no improvement beyond models with comorbidities at the time of the primary. The discriminative ability of all prediction models was best for mortality within 30 days and worst for mortality within 365 days. CONCLUSIONS: Comorbidity scores add little improvement beyond simpler models with age, gender and ASA grade for predicting mortality within one year after elective hip or knee replacement. The additional patient-specific information required to construct comorbidity scores must be balanced against their prediction gain when considering their utility.

Loss of skeletal muscle mass can be predicted by sarcopenia and reflects poor functional recovery at one year after surgery for geriatric hip fractures.

INTRODUCTION: Hip fractures in the elderly impact negatively on functional dependence, and carry great social costs and morbidity. We assessed the decline in muscle mass and functional outcomes following hip fracture surgery . MATERIAL AND METHODS: Thirty patients with a hip fracture (mean age: 80.8 years) were assessed using dual-energy X-ray absorptiometry and reassessed for changes in body composition 1 year after hip surgery. Baseline demographic data, sarcopenia, and bone mineral density were recorded. Body mass index (BMI), handgrip strength, appendicular skeletal muscle mass (ASM), total body fat percentage, and responses to questionnaires measuring quality of life and activities of daily living (ADL) before injury and 1 year after hip surgery were analyzed to identify changes. Associations with changes in ADL or quality of life were analyzed with time-variant independent variables. RESULTS: Significant losses in ADL were identified at the 1-year follow-up, at which time only 43% of patients had regained their preinjury ADL status. Additionally, the participants had lost an average of 4.63% of ASM. ASM loss was significantly higher in patients with baseline sarcopenia than in those without (mean loss: 9.18% and 1.15%, respectively). When confounders were controlled for, a greater loss of ASM and handgrip strength and larger increase in BMI were associated with greater decrease in ADL 1 year after hip surgery. CONCLUSION: Geriatric hip fracture patients may experience a significant loss of muscle mass, associated with impaired functional recovery 1 year after hip surgery, highlighting a potential treatment target of maintaining muscle mass to improve prognosis in these patients.

Biomechanics of subtrochanteric fracture fixation using short cephalomedullary nails: A finite element analysis.

A finite element analysis was performed to evaluate the stresses around nails and cortical bones in subtrochanteric (ST) fracture models fixed using short cephalomedullary nails (CMNs). A total 96 finite element models (FEMs) were simulated on a transverse ST fracture at eight levels with three different fracture gaps and two different distal locking screw configurations in both normal and osteoporotic bone. All FEMs were fixed using CMNs 200 mm in length. Two distal locking screws showed a wider safe range than 1 distal screw in both normal and osteoporotic bone at fracture gaps ≤ 3 mm. In normal bone FEMs fixed even with two distal locking screws, peak von Mises stresses (PVMSs) in cortical bone and nail constructs reached or exceeded 90% of the yield strength at fracture levels 50 mm and 0 and 50 mm, respectively, at all fracture gaps. In osteoporotic bone FEMs, PVMSs in cortical bone and nail constructs reached or exceeded 90% of the yield strength at fracture levels 50 mm and 0 and 50 mm, respectively, at a 1-mm fracture gap. However, at fracture gaps ≥ 2 mm, PVMSs in cortical bone reached or exceeded 90% of the yield strength at fracture levels ≥ 35 mm. PVMSs in nail showed the same results as 1-mm fracture gaps. PVMSs increased and safe range reduced, as the fracture gap increased. Short CMNs (200 mm in length) with two distal screws may be considered suitable for the fixation of ST transverse fractures at fracture levels 10 to 40 mm below the lesser trochanter in normal bone and 10 to 30 mm in osteoporotic bone, respectively, under the assumptions of anatomical reduction at fracture gap ≤ 3 mm. However, the fracture gap should be shortened to the minimum to reduce the risk of refracture and fixation failure, especially in osteoporotic fractures.

The Association Between Cholecystectomy and the Risk for Fracture: A Nationwide Population-Based Cohort Study in Korea.

Objectives: To evaluate the risk of fracture in individuals with a history of cholecystectomy in Korean population. Methods: Individuals (n = 143,667) aged ≥ 40 y who underwent cholecystectomy between 2010 and 2015 and the controls (n = 255,522), matched by age and sex, were identified from the database of the Korean National Health Insurance Services. The adjusted hazard ratio (aHR) and 95% confidence interval (CI) of fracture were estimated following cholecystectomy, and a Cox regression analysis was performed. Results: The incidence rates of all fractures, vertebral, and hip fractures were 14.689, 6.483 and 1.228 cases per 1000 person-years respectively in the cholecystectomy group, whereas they were 13.862, 5.976, and 1.019 cases per 1000 person-years respectively in the control group. After adjustment for age, sex, income, place of residence, diabetes mellitus, hypertension, dyslipidemia, smoking, alcohol drinking, exercise, and body mass index, patients who underwent cholecystectomy showed an increased risk of all fractures, vertebral fractures, and hip fractures (aHR [95% CI]: 1.095 [1.059-1.132], 1.134 [1.078-1.193], and 1.283 [1.139-1.444] for all fractures, vertebral fractures, and hip fractures, respectively). The risk of vertebral fractures following cholecystectomy was more prominent in the young age group (40 to 49 y) than in the old age group (≥ 65 y) (1.366 [1.082-1.724] vs. 1.132 [1.063-1.206], respectively). However, the incidence of hip fractures following cholecystectomy was not affected by age. Conclusion: Individuals who underwent cholecystectomy have an increased risk of fracture. In the younger population, the risk of vertebral fractures may be further increased following cholecystectomy.