Volunteer-led online group exercise for community-dwelling older people: a feasibility and acceptability study.

BACKGROUND: Despite the clear benefits of physical activity in healthy ageing, engagement in regular physical activity among community-dwelling older adults remains low, with common barriers including exertional discomfort, concerns with falling, and access difficulties. The recent rise of the use of technology and the internet among older adults presents an opportunity to engage with older people online to promote increased physical activity. This study aims to determine the feasibility and acceptability of training volunteers to deliver online group exercises for older adults attending community social clubs. METHODS: This was a pre-post mixed-methods study. Older adults aged ≥ 65 years attending community social clubs who provided written consent and were not actively participating in exercise classes took part in the feasibility study. Older adults, volunteers, and staff were interviewed to determine the acceptability of the intervention. The intervention was a once weekly volunteer-led online group seated strength exercises using resistance bands. The duration of the intervention was 6 months. The primary outcome measures were the feasibility of the intervention (determined by the number of volunteers recruited, trained, and retained, participant recruitment and intervention adherence) and its acceptability to key stakeholders. Secondary outcome measures included physical activity levels (Community Health Model Activities Programme for Seniors (CHAMPS) questionnaire), modified Barthel Index, Health-related quality of life (EQ-5D-5L), frailty (PRISMA-7) and sarcopenia (SARC-F), at baseline and 6 months. RESULTS: Nineteen volunteers were recruited, 15 (78.9%) completed training and 9 (47.3%) were retained after 1 year (mean age 68 years). Thirty older adults (mean age 77 years, 27 female) participated, attending 54% (IQR 37-67) of exercise sessions. Participants had no significant changes in secondary outcome measures, with a trend towards improvement in physical activity levels (physical activity in minutes per week at baseline was 1770 min, and 1909 min at six months, p = 0.13). Twenty volunteers, older adults, and staff were interviewed and found the intervention acceptable. The seated exercises were perceived as safe, manageable, and enjoyable. CONCLUSIONS: Trained volunteers can safely deliver online group exercise for community-dwelling older adults which was acceptable to older adults, volunteers, and club staff. TRIALS REGISTRATION: NCT04672200.

Evaluation of high-density, multi-contact nerve cuffs for activation of grasp muscles in monkeys.

OBJECTIVE: The objective of this work was to evaluate whether nerve cuffs can selectively activate hand muscles for functional electrical stimulation (FES). FES typically involves identifying and implanting electrodes in many individual muscles, but nerve cuffs only require implantation at a single site around the nerve. This method is surgically more attractive. Nerve cuffs may also more effectively stimulate intrinsic hand muscles, which are difficult to implant and stimulate without spillover to adjacent muscles. APPROACH: To evaluate its ability to selectively activate muscles, we implanted and tested the flat interface nerve electrode (FINE), which is designed to selectively stimulate peripheral nerves that innervate multiple muscles (Tyler and Durand 2002 IEEE Trans. Neural Syst. Rehabil. Eng. 10 294-303). We implanted FINEs on the nerves and bipolar intramuscular wires for recording compound muscle action potentials (CMAPs) from up to 20 muscles in each arm of six monkeys. We then collected recruitment curves while the animals were anesthetized. MAIN RESULT: A single FINE implanted on an upper extremity nerve in the monkey can selectively activate muscles or small groups of muscles to produce multiple, independent hand functions. SIGNIFICANCE: FINE cuffs can serve as a viable supplement to intramuscular electrodes in FES systems, where they can better activate intrinsic and extrinsic muscles with lower currents and less extensive surgery.

Experiment-based modelling of grain boundary ß-phase (Mg2Al3) evolution during sensitisation of aluminium alloy AA5083.

An empirical model for the evolution of ß-phase (Mg2Al3) along grain boundaries in aluminium alloy AA5083 (Al-Mg-Mn) during isothermal exposures is proposed herein. Developing a quantitative understanding of grain boundary precipitation is important to interpreting intergranular corrosion and stress corrosion cracking in this alloy system. To date, complete ab initio models for grain boundary precipitation based upon fundamental principles of thermodynamics and kinetics are not available, despite the critical role that such precipitates play in dictating intergranular corrosion phenomena. Empirical models can therefore serve an important role in advancing the understanding of grain boundary precipitation kinetics, which is an approach applicable beyond the present context. High resolution scanning electron microscopy was to quantify the size and distribution of ß-phase precipitates on Ga-embrittled intergranular fracture surfaces of AA5083. The results are compared with the degree of sensitisation (DoS) as judged by nitric acid mass loss testing (ASTM-G67-04), and discussed with models for sensitisation in 5xxx series Al-alloys. The work herein allows sensitisation to be quantified from an unambiguous microstructural perspective.

Neuropsychological profiles of familial Alzheimer's disease associated with mutations in the presenilin 1 and amyloid precursor protein genes.

Patients with familial Alzheimer's disease and a subset known to have presenilin mutations were compared with sporadic cases on a comprehensive battery of cognitive tests. These included measures of memory, intelligence, language and perception. The three groups were very comparable, in terms of severity, on global measures of dementia. However, their profiles/patterns of cognitive impairment differed in two respects; the group with sporadic Alzheimer's disease were significantly more impaired on tests of object naming and object perception than either the group with familial Alzheimer's disease or group with familial Alzheimer's disease and presenilin mutations, yet they scored at a significantly higher level on the measure of verbal intelligence. This study provides further evidence of the heterogeneity of the disease process.

Presymptomatic cognitive deficits in individuals at risk of familial Alzheimer's disease. A longitudinal prospective study.

A longitudinal study of asymptomatic individuals at risk of autosomal dominant familial Alzheimer's disease was performed to assess the earliest clinical and neuropsychological features of the disease. Over a 6-year period, 63 subjects underwent serial assessments. During the study, 10 subjects developed symptoms of episodic memory loss and subsequently progressed to fulfil criteria for possible or probable Alzheimer's disease. The mean time (+/-SD) from first assessment to the appearance of symptoms was 2.6+/-1.4 years. The subjects who remained well were similar to those who became clinically affected in terms of age, family history and initial Mini-Mental State Examination. Individuals who later became clinically affected already had significantly lower verbal memory (P=0.003) and performance IQ (P=0.030) scores at their first assessment, when they were ostensibly unaffected. Subsequent assessments showed progressive decline in multiple cognitive domains. Blinded assessment of serial imaging revealed the appearance of diffuse cerebral and medial temporal lobe atrophy in subjects only once they were clinically affected. These findings imply that in familial Alzheimer's disease cognitive decline predates symptoms by several years and that verbal memory deficits precede more widespread deterioration. This may have implications for the detection and treatment of Alzheimer's disease at an early stage.

Evaluation of new plate designs for symphysis pubis internal fixation.

The purpose of this study was to evaluate and compare biplanar and other newly designed plates used for pubic symphysis internal fixation to other standard plates. Our data demonstrate that neither of the newly designed symphyseal plates, curved (Zimmer four-hole plate with either two or four 4.5-mm cortical screws) nor the biplanar (Zimmer six-hole plate with four 4.5-mm cortical screws in one plane and two 4.5-mm cortical screws in another) significantly reduce motion more than the other plates tested (Synthes two-hole 4.5-mm dynamic compression plate with two 6.5-mm cancellous screws and six-hole 3.5-mm reconstruction plate with four 3.5-mm cortical screws). All of the plate constructs were able to restore motion to nearly that of the intact symphysis pubis and sacroiliac joint. In summary, using the anteroposterior compression disruption pattern and model, the disrupted symphysis does gap under load but has no effect on sacroiliac joint gapping. It does permit increase in relative flexion angles between the wings of the pelvis. All of the plate systems tested restore normal gap motion at the symphysis and normal sacroiliac joint flexion.

Predictors for frequent esophageal dilations of benign peptic strictures.

Recurrence of esophageal peptic stricture necessitating repeated dilation treatments remains a problem for many patients despite optimal acid suppressive therapy. The factors associated with frequent relapses are poorly understood. We studied retrospectively a population of 58 patients with benign peptic strictures and dysphagia treated by esophageal dilation and followed for 66.5 +/- 6.7 months. Data was collected for age, sex, heartburn, weight loss, esophagitis, Barrett's esophagus, number of dilation treatments during the first year of follow-up, frequency and number of subsequent dilation treatments, type of dilator used, and history of other concurrent treatments. Patients who lacked heartburn (P = 0.007) or who reported a history of weight loss (P = 0.006) at the time of their initial presentation required more frequent dilations during the first year of follow-up. The mean number of dilations in year 1 was 6.2 +/- 0.9 for patients lacking heartburn versus 3.2 +/- 0.5 for patients with heartburn (P = 0.004), and 9.0 +/- 1.8 for patients who reported weight loss versus 4.1 +/- 0.5 (P = 0.006) for those who did not. The patients requiring frequent treatment during their first year also required frequent subsequent dilations because of stricture recurrence (P < 0.0001). We did not demonstrate any relationship between the other factors studied and treatment frequency. These observations suggest that patients who require frequent retreatment for recurrent peptic stricture are more likely to provide a history of weight loss and less likely to complain of heartburn at initial presentation. The pattern of frequent repeat dilation for recurrent peptic strictures is established during the first year of follow-up.

Alcoholism in hereditary hemochromatosis revisited: prevalence and clinical consequences among homozygous siblings.

The relationship between alcoholism and hereditary hemochromatosis remains controversial. Previous studies have included patients with alcoholic siderosis rather than hereditary hemochromatosis. In this retrospective study, the clinical features, iron status, alcohol history, liver histology, and long-term survival were reviewed in 105 homozygotes for hemochromatosis using rigid diagnostic criteria including an HLA identical sibling with iron overload. Heavy alcohol consumption (>80 g ethanol/day) was found in 15 percent of hemochromatosis patients. Histological features of alcoholic liver disease (Mallory's hyaline bodies, pericentral fibrosis, polymorphonuclear infiltrate, and fatty infiltration) were uncommon in hemochromatosis. Hemochromatosis patients with heavy alcohol consumption had a higher prevalence of cirrhosis than hemochromatosis patients without heavy alcohol consumption. Hepatic iron concentration and hepatic iron index did not significantly differ between these two hemochromatosis groups. Long-term survival was significantly reduced in patients with heavy alcohol consumption (mean follow-up, 9.22 years). This suggests that chronic alcohol consumption has an additive hepatotoxic effect despite the paucity of histological features of alcoholic liver disease.

Radiographic recognition of the sacral alar slope for optimal placement of iliosacral screws: a cadaveric and clinical study.

Malpositioning of iliosacral screws happens more often when common variations in the morphology of the upper sacral segments are unrecognized. Radiological-anatomic correlations of sacral anatomy were studied in 10 fresh-frozen cadaveric pelvises without evidence of skeletal disease, obtained from six male and four female donors. Eighty consecutive patients with complicated pelvic fractures treated operatively by the same surgeon using percutaneously placed iliosacral screws were evaluated. Variations in the sacral alar anatomy and slope found in upper sacral segmentation anomalies are common. Surgically important and predictable abnormal morphological patterns can be easily identified using pelvic outlet and lateral sacral plain radiographs along with computed tomographic scans. On the true lateral projections, the iliac cortical density adjacent to the sacroiliac joint parallels the sacral alar slope and is almost always caudal and posterior to it; it delineates the anterior extent of the "safe zone" for iliosacral screw insertion. Thus, the lateral sacral image provides the surgeon with a better understanding of the sacral alar slope and can help prevent iliosacral screw placement errors. The lateral sacral image should always be used intraoperatively with the inlet and outlet images to guide iliosacral screw placement.

Analysis of the torque applied to bone screws by trauma surgeons. Comparisons based on years of experience and material of implant construction.

Stability of an internal fixation construct is dependent on the torque placed on the screws holding the plate, the number of screws in the construct, and the number of cortices purchased by each screw. This study addresses the ability of surgeons to apply uniform torque and the variability between stainless steel and titanium. A total of 630 measurements were made by trained orthopedists using a device to measure the torque applied to 3.5 mm screws when tightening them to a plate. Variations were found to be significant depending on the number of years the orthopedist was in practice and the type of construct material used. The average torque applied to a stainless steel construct is 5.82 in-lb, while the torque applied to titanium is 5.41 in-lb (P < 0.01). The longer an orthopedist is in practice, the more torque will be applied to the screw/plate construct.

Hemodynamically unstable pelvic fractures.

This article reviews the past and present data regarding the evaluation and resuscitation of patients with concomitant pelvic fractures and hemodynamic instability. The emphasis is that successful treatment requires a concerted and aggressive team approach from all disciplines. Timely care has proven to be the single most important factor in patient survivorship. Recent advances such as emergency posterior frames will allow simultaneous evaluation and resuscitation. A treatment algorithm is presented for emergency care.

The mangled lower extremity: can salvage be predicted?

The ability to predict amputation following combined orthopedic, vascular and soft tissue trauma to an extremity could eliminate prolonged attempts at salvage of a doomed limb. We reviewed our experience with 48 mangled lower extremities in 46 patients. Twenty-one penetrating wounds and 25 blunt injuries occurred in 37 men and nine women ranging in age from 3 to 59 years. Severity of injuries to muscle, skin, and major nerves were strongly interrelated (r = 0.49 to 0.74, P < 0.001), but there were no correlations between injuries to these tissues and severity of bone injury (r < 0.19, P > 0.20). Twenty-four limbs were salvaged, and 24 were amputated. Increased severity of soft tissue injury was associated with a greater probability of limb loss (P < 0.001), but limb salvage or amputation could not be predicted accurately by any variable or group of variables such as age, mechanism of injury, Injury Severity Score, presence of shock, level of injury, venous injury or repair, sequence of repair (vascular vs skeletal), time of fasciotomy, arteriography, blood requirement, or duration of ischemia. Amputation was best predicted by severity of injury to the sciatic or tibial nerves (P < 0.001), and by failure of arterial repair (P < 0.01). Severe extremity injuries require a coordinated approach and decisions regarding amputation require careful judgement. These decisions cannot always be made at the time of presentation or during the initial operation. If after revascularization and skeletal stabilization the extremity is clearly nonviable or remains insensate, then delayed amputation can be performed under more controlled circumstances.

Lower extremity fracture fixation in head-injured patients.

Compared with nonsurgical management or delayed repair, early fracture fixation can reduce the incidence of pulmonary complications in patients with long-bone fractures of the lower extremities. Blunt trauma victims often have multiple nonskeletal injuries that might influence the risk of pulmonary complications, and when head injuries are present it has been a common practice to delay nonemergent operations for several days to protect the injured brain. We conducted a retrospective review of 114 patients with multiple trauma whose injuries included head trauma and a fracture of the neck or shaft of the femur or shaft of the tibia to determine if delayed stabilization of lower extremity fractures increased the risk of pulmonary complications or reduced the risk of cerebral complications. Forty-six patients underwent surgical fixation of their fractures within 24 hours of injury (early fixation), 26 patients had their fractures repaired more than 24 hours after injury (late fixation), and 42 patients did not undergo surgical fracture fixation. The risk of pulmonary complications was not related to the timing of surgical fracture fixation but was strongly influenced by the severity of injuries to the head and to the chest (p less than 0.001). Furthermore, a delay in fracture fixation did not protect the injured brain; the risk of CNS events was determined by the severity of the head injury (p less than 0.0001). Early fracture fixation in patients with head injury may be appropriate because it simplifies patient care and does not seem to worsen the head injury, but it does not prevent pulmonary complications in these high-risk patients.

Immediate internal fixation of open, complex tibial plateau fractures: treatment by a standard protocol.

A retrospective review of 46 consecutive patients with complex (Schatzker V and VI) tibial plateau fractures treated at Harborview Medical Center between 1984 and 1989, disclosed a subset of 14 grade II or III (Gustilo) open injuries. We wished to determine the incidence of infection, union rate, and the number of operations required to achieve a satisfactory result, based on a treatment protocol: alignment and splinting of fracture at the scene of injury if possible, antibiotics administered in the emergency room (ER) and continued for 48 h, and admission of patient to the operating room as quickly as possible for irrigation and thorough debridement of the wound, immediate rigid internal fixation, and delayed primary closure at 5 days. No acute deep infection or radiographic evidence of implant loosening was noted. The final outcome was graded by Hospital for Special Surgery (HSS) Knee Rating Score at an average follow-up of 2 years 7 months. Radiographs were reviewed for reduction and evidence of postoperative change in reduction. The average HSS Functional Score was 81.5, and Knee Score was 84.6. Of 14 limbs, 10 had an excellent radiographic grade that did not change at follow-up, 2 had a satisfactory grade, and 2 had a poor grade.

Open tibia fracture caused by femoral shaft fragment.

Open tibia fractures and open femoral shaft fractures are commonplace in today's motorized society. We report a unique combination of injuries sustained by two patients treated at our institution.