Analysis of Vertical Ground Reaction Force Variables during a Sit to Stand Task in Participants Recovering from a Hip Fracture

Background: A Sit to Stand task following a hip fracture may be achieved through compensations (e.g. bilateral arms and uninvolved lower extremity), not restoration of movement strategies of the involved lower extremity. The primary purpose was to compare upper and lower extremity movement strategies using the vertical ground reaction force during a Sit to Stand task in participants recovering from a hip fracture to control participants. The secondary purpose was to evaluate the correlation between vertical ground reaction force variables and validated functional measures. Methods: Twenty eight community dwelling older adults, 14 who had a hip fracture and 14 control participants completed the Sit to Stand task on an instrumented chair designed to measure vertical ground reaction force, performance based tests (Timed up and go, Berg Balance Scale and Gait Speed) and a self report Lower Extremity Measure. A MANOVA was used to compare functional scales and vertical ground reaction force variables between groups. Bivariate correlations were assessed using Pearson Product Moment correlations. Findings: The vertical ground reaction force variables showed significantly higher bilateral arm force, higher uninvolved side peak force and asymmetry between the involved and uninvolved sides for the participants recovering from a hip fracture (Wilks\u27 Lambda=3.16, P=0.019). Significant correlations existed between the vertical ground reaction force variables and validated functional measures. Interpretation: Participants recovering from a hip fracture compensated using their arms and the uninvolved side to perform a Sit to Stand. Lower extremity movement strategies captured during a Sit to Stand task were correlated to scales used to assess function, balance and falls risk

Influence of Upper Extremity Assistance on Lower Extremity Force Application Symmetry in Individuals Post–Hip Fracture During the Sit-to-Stand Task

STUDY DESIGN: Controlled laboratory study using a cross-sectional design. OBJECTIVES: To compare lower extremity force applications during a sit-to-stand (STS) task with and without upper extremity assistance in older individuals post–hip fracture to those of age matched controls. BACKGROUND: A recent study documented the dependence on upper extremity assistance and the uninvolved lower limb during an STS task in individuals post–hip fracture. This study extends this work by examining the effect of upper extremity assistance on symmetry of lower extremity force applications. METHODS: Twenty-eight community-dwelling elderly subjects, 14 who had recovered from a hip fracture and 14 controls, participated in the study. All participants were independent ambulators. Four force plates were used to determine lower extremity force applications during an STS task with and without upper extremity assistance. The summed vertical ground reaction forces (vGRFs) of both limbs were used to determine STS phases (preparation/rising). The lower extremity force applications were assessed statistically using analysis of variance models. RESULTS: During the preparation phase, sideto-side symmetry of the rate of force development was significantly lower for the hip fracture group for both STS tasks (P\u3c.001). During the rising phase, the vGRF impulse of the involved limb was significantly lower for the hip fracture group for both STS tasks (P = .045). The vGRF impulse for the uninvolved limb was significantly increased when participants with hip fracture did not use upper extremity assistance compared to elderly controls (P = .002). This resulted in a significantly lower vGRF symmetry for the hip fracture group during both STS tasks (P\u3c.001). CONCLUSION: Participants with hip fracture who were discharged from rehabilitative care demonstrated decreased side-to-side symmetry of lower extremity loading during an STS task, irrespective of whether upper extremity assistance was provided. These findings suggest that learned motor control strategies may influence movement patterns post–hip fracture

Use of Denosumab in Children With Osteoclast Bone Dysplasias: Report of Three Cases.

Denosumab has been used successfully to treat disease-associated osteoclast overactivity, including giant cell tumor of bone. Given its mechanism of action, denosumab is a potent potential treatment of other osteoclast bone dysplasias including central giant cell granuloma (CGCG), aneurysmal bone cyst (ABC), and cherubism. Relatively little is known about the safety and efficacy of denosumab in patients with these conditions, especially in children. We report on 3 pediatric patients treated with denosumab over a 3-year period at UCLA Medical Center (Los Angeles and Santa Monica, CA, USA): a 12-year-old with recurrent ABC of the pelvis, a 14-year-old with CGCG of the mandible, and a 12-year-old with cherubism. All were started on a 1-year course of 15 doses 120 mg s.c., given monthly with two loading doses on day 8 and 15. All patients demonstrated rapid and pronounced clinical improvement while on denosumab, including a significant reduction in pain and sclerosis of lytic lesions on radiographs. Within 1 month of initiating therapy, 2 patients experienced hypocalcemia (Common Terminology Criteria for Adverse Events [CTCAE] grade 2) and hypophosphatemia, with 1 patient experiencing symptoms. One patient went on to experience symptomatic rebound hypercalcemia (CTCAE grade 4) 5 months after completing therapy, requiring bisphosphonates and calcitonin. For the second patient, we developed a schedule to wean denosumab involving the progressive lengthening of time between doses from 1 to 4 months in 1-month increments before cessation. We found that denosumab therapy results in significant clinical and radiographic improvement for pediatric patients with nonresectable ABC, CGCG, and cherubism. Problems with serum calcium may be more common in younger patients, with symptomatic and protracted rebound hypercalcemia after cessation of therapy the most significant. We present a potential solution to this problem with progressive spacing of doses. Potential serious adverse events from alterations in calcium homeostasis should be explored in prospective clinical trials. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research

Proceedings of the 2022 Santa Fe Bone Symposium : Current concepts in the care of patients with osteoporosis and metabolic bone diseases

The 22nd Annual Santa Fe Bone Symposium (SFBS) was a hybrid meeting held August 5-6, 2022, with in-person and virtual attendees. Altogether, over 400 individuals registered, a majority of whom attended in-person, representing many states in the USA plus 7 other countries. The SFBS included 10 plenary presentations, 2 faculty panel discussions, satellite symposia, Bone Health & Osteoporosis Foundation Fracture Liaison Service Boot Camp, and a Project ECHO workshop, with lively interactive discussions for all events. Topics of interest included fracture prevention at different stages of life; how to treat and when to change therapy; skeletal health in cancer patients; advanced imaging to assess bone strength; the state of healthcare in the USA; osteosarcopenia; vitamin D update; perioperative bone health care; new guidelines for managing primary hyperparathyroidism; new concepts on bone modeling and remodeling; and an overview on the care of rare bone diseases, including hypophosphatasia, X-linked hypophosphatemia, tumor induced osteomalacia, osteogenesis imperfecta, fibrodysplasia ossificans progressiva, and osteopetrosis. The SFBS was preceded by the Santa Fe Fellows Workshop on Osteoporosis and Metabolic Bone Diseases, a collaboration of the Endocrine Fellows Foundation and the Osteoporosis Foundation of New Mexico. From the Workshop, 4 participating fellows were selected to give oral presentations at the bone symposium. These proceedings represent the clinical highlights of 2022 SFBS presentations and the discussions that followed, all with the aim of optimizing skeletal health and minimizing the consequences of fragile bones

Accelerated fracture healing

Acceleration of the fracture healing process would have farreaching benefits for both civilians and military personnel. Decreasing the time to return to complete function would reduce medical costs, enhance quality of life by decreasing pain and increasing mobility, accelerate the return of professional athletes to their sport, and decrease the time for military recruits to enter active duty after injuries incurred in basic training. Moreover, augmenting the healing process may prevent the long-term disability caused by fracture nonunion. Currently available pharmaceutical agents may allow us to realize this goal. However, these agents need to be tested in prospective randomized clinical trials. Copyright 2006 by the American Academy of Orthopaedic Surgeons

Advances in the Molecular Biology of Chondrosarcoma

Chondrosarcoma (CS) is a highly treatment-resistant tumor of cartilage-producing cells and the second most common primary bone malignancy following osteosarcoma. As CS is refractory to available chemotherapy and radiotherapy, aggressive surgical resection with wide margins remains the only effective treatment option. Cancer immunotherapies and targeted therapies have failed in clinical trials, and no prognostic biomarkers exist within the clinic. A deeper understanding of the molecular biology and dysregulated pathways in CS is necessary for more effective precision therapies. In response, several large-scale genetic and epigenetic studies have recently emerged, with several notable pathways holding therapeutic promise. In this review, we summarize the emerging works on CS biology, focusing on both genomic and epigenomic mechanisms and targets. These studies highlight several valuable clinical opportunities for earlier detection, prognostic accuracy, and therapeutic targeting that may potentially improve patient outcomes

Tenosynovial giant cell tumor: case report of a patient effectively treated with pexidartinib (PLX3397) and review of the literature.

BackgroundTenosynovial giant cell tumors (TGCTs) or giant cell tumors of tendon sheath are neoplasms that arise in the synovium. They can be categorized as nodular (localized) or diffuse type (D-TGCT). Historically, surgery has been the mainstay of therapy, but diffuse type disease recurs at a high rate and treatment often requires increasingly morbid procedures. Elucidation of the importance of the colony-stimulating factor (CSF1)/CSF1 receptor (CSF1R) pathway in the pathogenesis of this disease has created significant interest in targeting this pathway as a novel TGCT treatment approach. Pexidartinib, a selective tyrosine kinase inhibitor against CSF1R, showed an 83% disease control rate (52% with partial response and 31% with stable disease) in a recent phase 1 study of patients with TGCT.Case presentationWe present an illustrative example of a TGCT patient who would have required a morbid operation who derived considerable clinical benefit from pexidartinib treatment. Her tumor volume decreased by 48% after 4 months of treatment, and 55 months after starting treatment the patient exhibits continued disease stability with minimal clinical symptoms, and significant improvement in functional status.ConclusionsThis case illustrates the effectiveness of systemic therapy in controlling a disease associated with high surgical morbidity. This approach may be especially useful in the treatment of extra-articular disease which often invades neurovascular bundles; as the effectiveness in metastatic disease is still unknown. In the future, systemic treatment for TGCT may be appropriate for the neoadjuvant setting to decrease disease burden prior to surgery with the aim of decreasing recurrence rates. However, properly designed prospective studies will need to be carried out to answer these questions

Case Discussion

This case presents a discussion of a frail 98-year-old woman in hospice care, with a history of dementia, previous hip fracture, and anemia, who is admitted with a left intertrochanteric fracture. Care is coordinated and expedited by an interdisciplinary team to optimize her outcome, in the context of her goals of care

Sun Glint Correction of High and Low Spatial Resolution Images of Aquatic Scenes: a Review of Methods for Visible and Near-Infrared Wavelengths

Sun glint, the specular reflection of light from water surfaces, is a serious confounding factor for remote sensing of water column properties and benthos. This paper reviews current techniques to estimate and remove the glint radiance component from imagery. Methods for processing of ocean color images use statistical sea surface models to predict the glint from the sun and sensor positions and wind data. Methods for higher resolution imaging, used in coastal and shallow water mapping, estimate the glint radiance from the near-infrared signal. The effects of some current methods are demonstrated and possibilities for future techniques are briefly addressed

Dementia and Hip Fractures

Dementia and hip fractures are 2 conditions that are seen primarily in older adults, and both are associated with substantial morbidity and mortality. An individual with dementia is up to 3 times more likely than a cognitively intact older adult to sustain a hip fracture. This may occur via several mechanisms, including (1) risk factors that are common to both outcomes; (2) the presence of dementia increasing hip fracture incidence via intermediate risk factors, such as falls, osteoporosis, and vitamin D; and (3) treatment of dementia causing side effects that increase hip fracture risk. We describe a model that applies these 3 mechanisms to explain the relationship between dementia and hip fractures. Comprehensive understanding of these pathways and their relative influence on the outcome of hip fracture will guide the development of effective interventions and potentially improve prevention efforts