Katie Jane Sheehan

The influence of excess body mass on adult gait

BACKGROUND This study aimed to assess the presentation of gait for adults who are overweight, independent of the confounding influence of velocity. METHODS Cross sectional study design. Twenty-five adults of a healthy weight were matched by age, gender, height and velocity to twenty-five adults who were overweight. Participants traversed a 10m walkway embedded with 2 AMTI force platforms (AMTI BP400600 Force Platforms: Advanced Mechanical Technologies, Inc., Watertown, MA, USA) and running between 2 CODA Dual CX1 sensors (CODA CX1: Charnwood Dynamics, Barrow on Soar, Leicestershire, England). Temporal-spatial parameters, maximum ground reaction forces, maximum joint powers, and three dimensional kinematic and kinetic parameters at the 7 events of the gait cycle were assessed. FINDINGS With velocity accounted for, relatively few changes in the presentation of gait were seen for adults who were overweight. Alterations included increased stance phase duration, hip flexion, knee flexion, hip abduction, and knee varus for overweight adults. A reduction in hip abductor moment normalised for body mass was noted for overweight adults. Absolute maximum ground reaction forces were increased while maximum hip power absorption was reduced for overweight adults. INTERPRETATION Changes were seen at the hip and knee during the swing phase of gait. During swing there is a stronger association with soft tissue injury as compared to joint injury. Overweight individuals were seen to adopt few alterations during the stance phase to accommodate for the increased absolute ground reaction forces. As a result the joint surfaces of overweight adults are exposed to increased loading.

Early identification of declining balance in higher functioning older adults, an inertial sensor based method

Higher functioning older adults rarely have their balance assessed clinically and as such early decline in balance is not captured. Early identification of declining balance would facilitate earlier intervention and improved management of the ageing process. This study sought to determine if (a) a once off inertial sensor measurement and (b) changes in inertial sensor measurements one year apart can identify declining balance for higher functioning older adults. One hundred and nineteen community dwelling older adults (58 males; 72.5±5.8 years) completed a timed up and go (TUG) instrumented with inertial sensors and the Berg balance scale (BBS) at two time points, one year apart. Temporal and spatio-temporal gait parameters as well as angular velocity and turn parameters were derived from the inertial sensor data. A change in balance from baseline to follow-up was determined by sub-components of the BBS. Changes in inertial sensor parameters from baseline to follow-up demonstrated strong association with balance decline in higher functioning older adults (e.g. mean medial-lateral angular velocity odds ratio=0.2; 95% CI: 0.1-0.5). The area under the Receiver operating characteristic curve (AUC) ranged from 0.8 to 0.9, a marked improvement over change in TUG time alone (AUC 0.6-0.7). Baseline inertial sensor parameters had a similar association with declining balance as age and TUG time. For higher functioning older adults, the change in inertial sensor parameters over time may reflect declining balance. These measures may be useful clinically, to monitor the balance status of older adults and facilitate earlier identification of balance deficits.

Constructing an episode of care from acute hospitalization records for studying effects of timing of hip fracture surgery

Episodes of care defined by the event of hip fracture surgery are widely used for the assessment of surgical wait times and outcomes. However, this approach does not consider nonoperative deaths, implying that survival time begins at the time of procedure. This approach makes treatment effect implicitly conditional on surviving to treatment. The purpose of this article is to describe a novel conceptual framework for constructing an episode of hip fracture care to fully evaluate the incidence of adverse events related to time after admission for hip fracture. This admission‐based approach enables the assessment of the full harm of delay by including deaths while waiting for surgery, not just deaths after surgery. Some patients wait until their conditions are optimized for surgery, whereas others have to wait until surgical service becomes available. We provide definitions, linkage rules, and algorithms to capture all hip fracture patients and events other than surgery. Finally, we discuss data elements for stratifying patients according to administrative factors for delay to allow researchers and policymakers to determine who will benefit most from expedited access to surgery.

In-hospital mortality after hip fracture by treatment setting

Background: Where patients with hip fracture undergo treatment may influence their outcome. We compared the risk of in-hospital death after hip fracture by treatment setting in Canada. Methods: We examined all discharge abstracts from the Canadian Institute for Health Information with diagnosis codes for hip fracture involving patients 65 years and older who were admitted to hospital with a nonpathological first hip fracture between Jan. 1, 2004, and Dec. 31, 2012, in Canada (excluding Quebec). We compared the risk of in-hospital death, overall and after surgery, between teaching hospitals and community hospitals of various bed capacities, accounting for variation in length of stay. Results: Compared with the number of deaths per 1000 admissions at teaching hospitals, there were an additional 3 (95% confidence interval [CI] 1–6), 14 (95% CI 10–18) and 43 (95% CI 35–51) deaths per 1000 admissions at large, medium and small community hospitals, respectively. For the risk of in-hospital death overall, the adjusted odds ratios (ORs) were 1.05 (95% CI 0.99–1.11), 1.16 (95% CI 1.09–1.24) and 1.44 (95% CI 1.31–1.57) at large, medium and small community hospitals, respectively, compared with teaching hospitals. For the risk of postsurgical death in hospital, the adjusted ORs were 1.06 (95% CI 1.00–1.13), 1.13 (95% CI 1.04–1.23) and 1.18 (95% CI 0.87–1.60) at large, medium and small community hospitals, respectively. Interpretation: Compared with teaching hospitals, the risk of in-hospital death among patients with hip fracture was higher at medium and small community hospitals, and the risk of in-hospital death after surgery was higher at medium community hospitals. No differences were found between teaching and large community hospitals. Future research should examine the role of volume, demand and bed occupancy for observed differences.

Risk of second hip fracture persists for years after initial trauma

BACKGROUND Secondary prevention often targets women who suffer from higher rates of second hip fracture than men, especially in the early years after first fracture. Yet, the occurrence of second hip fracture by certain times also depends on the death rate, which is higher in men than women. We compared the risk of sustaining second hip fracture by a certain time between women and men remaining alive at that time. METHODS We retrieved 38,383 hospitalization records of patients aged 60 years or older, who were discharged alive after admission for hip fracture surgery between 1990 and 2005 in British Columbia, Canada. The outcome variable was the time to a subsequent hip fracture. RESULTS During ten years of follow-up, 2,902 (8%) patients sustained a second hip fracture, and 21,428 (56%) died before sustaining a second hip fracture. The risk of second hip fracture in the surviving post-fracture patients was higher in women than in men: 2% vs 2%, 5% vs 4%, 9% vs 7%, 15% vs 13%, and 35% vs 30% at 1, 2, 3, 5, and 10 years after initial trauma, respectively, crude OR=1.25 (95% CI: 1.13-1.39). However, the risk did not differ between women and men after adjustment, OR=1.09 (95% CI: 0.98-1.21). CONCLUSIONS The risk of second hip fracture persists for at least ten years among hip fracture survivors, and therefore secondary prevention should continue beyond an early post-fracture period. Women and men have similar risks of second hip fracture and both should be considered for secondary prevention.

Patient and system factors of time to surgery after hip fracture: a scoping review

Objectives It is disputed whether the time a patient waits for surgery after hip fracture increases the risk of in-hospital death. This uncertainty matters as access to surgery following hip fracture may be underprioritised due to a lack of definitive evidence. Uncertainty in the available evidence may be due to differences in characteristics of patients, their injury and their care. We summarised the literature on patients and system factors associated with time to surgery, and collated proposed mechanisms for the associations. Methods We used the framework developed by Arksey and O’Malley and Levac et al for synthesis of factors and mechanisms of time to surgery after hip fracture in adults aged >50 years, published in English, between 1 January 2000 and 28 February 2017, and indexed in MEDLINE, EMBASE, CINAHL or Ageline. Proposed mechanisms for reported associations were extracted from discussion sections. Results We summarised evidence from 26 articles that reported on 24 patient and system factors of time to surgery post hip fracture. In total, 16 factors were reported by only one article. For 16 factors we found proposed mechanisms for their association with time to surgery which included surgical readiness, available resources, prioritisation and out-of-hours admission. Conclusions We identified patient and system factors associated with time to surgery after hip fracture. This new knowledge will inform evaluation of the putative timing–death association. Future interventions should be designed to influence factors with modifiable mechanisms for delay.

Hospital mortality after hip fracture surgery in relation to length of stay by care delivery factors: A database study

Abstract Two hypotheses were offered for the effect of shorter hospital stays on mortality after hip fracture surgery: worsening the quality of care and shifting death occurrence to postacute settings. We tested whether the risk of hospital death after hip fracture surgery differed across years when postoperative stays shortened, and whether care factors moderated the association. Analysis of acute hospital discharge abstracts for subgroups defined by hospital type, bed capacity, surgical volume, and admission time. 153,917 patients 65 years or older surgically treated for first hip fracture. Risk of hospital death. We found a decrease in the 30-day risk of hospital death from 7.0% (95%CI: 6.6–7.5) in 2004 to 5.4% (95%CI: 5.0–5.7) in 2012, with an adjusted odds ratio [OR] 0.71 (95%CI: 0.63–0.80). In subgroup analysis, only large community hospitals showed the reduction of ORs by calendar year. No trend was observed in teaching and medium community hospitals. By 2012, the risk of death in large higher volume community hospitals was 34% lower for weekend admissions, OR = 0.66 (95%CI: 0.46–0.95) and 39% lower for weekday admissions, OR = 0.61 (95%CI: 0.40–0.91), compared to 2004. In large lower volume community hospitals, the 2012 risk was 56% lower for weekend admissions, OR = 0.44 (95%CI: 0.26–0.75), compared to 2004. The risk of hospital death after hip fracture surgery decreased only in large community hospitals, despite universal shortening of hospital stays. This supports the concern of worsening the quality of hip fracture care due to shorter stays.

Mortality by timing of hip fracture surgery: factors and relationships at play

Abstract: In hip fracture care, it is disputed whether mortality worsens when surgery is delayed. This knowledge gap matters when hospital managers seek to justify resource allocation for prioritizing access to one procedure over another. Uncertainty over the surgical timing-death association leads to either surgical prioritization without benefit or the underuse of expedited surgery when it could save lives. The discrepancy in previous findings results in part from differences between patients who happened to undergo surgery at different times. Such differences may produce the statistical association between surgical timing and death in the absence of a causal relationship. Previous observational studies attempted to adjust for structure, process, and patient factors that contribute to death, but not for relationships between structure and process factors, or between patient and process factors. In this article, we (1) summarize what is known about the factors that influence, directly or indirectly, both the timing of surgery and the occurrence of death; (2) construct a dependency graph of relationships among these factors based explicitly on the existing literature; (3) consider factors with a potential to induce covariation of time to surgery and the occurrence of death, directly or through the network of relationships, thereby explaining a putative surgical timing-death association; and (4) show how age, sex, dependent living, fracture type, hospital type, surgery type, and calendar period can influence both time to surgery and occurrence of death through chains of dependencies. We conclude by discussing how these results can inform the allocation of surgical capacity to prevent the avoidable adverse consequences of delaying hip fracture surgery.

Prognostic factors of functional outcome after hip fracture surgery: a systematic review

Objective this systematic review aimed to identify immutable and modifiable prognostic factors of functional outcomes and their proposed mechanism after hip fracture surgery. Design systematic search of MEDLINE, Embase, CINAHL, PEDRO, OpenGrey and ClinicalTrials.gov for observational studies of prognostic factors of functional outcome after hip fracture among surgically treated adults with mean age of 65 years and older. Study selection, quality assessment, and data extraction were completed independently by two reviewers. The Quality in Prognosis Studies Tool was used for quality assessment and assigning a level of evidence to factors. Proposed mechanisms for reported associations were extracted from discussion sections. Results from 33 studies of 9,552 patients, we identified 25 prognostic factors of functional outcome after hip fracture surgery. We organised factors into groups: demographics, injury and comorbidities, body composition, complications, and acute care. We assigned two factors a weak evidence level-anaemia and cognition. We assigned Parkinsons disease an inconclusive evidence level. We could not assign an evidence level to the remaining 22 factors due to the high risk of bias across studies. Frailty was the proposed mechanism for the association between anaemia and functional outcome. Medication management, perceived potential, complications and time to mobility were proposed as mechanisms for the association between cognition and functional outcome. Conclusion we identified one modifiable and one immutable prognostic factor for functional outcomes after hip fracture surgery. Future research may target patients with anaemia or cognitive impairment by intervening on the prognostic factor or the underlying mechanisms.

Feasibility of using administrative data for identifying medical reasons to delay hip fracture surgery: a Canadian database study

Purpose Failure to account for medically necessary delays may lead to an underestimation of early surgery benefits. This study investigated the feasibility of using administrative data to identify the National Institute for Health and Care Excellence (NICE) 124 guideline list of conditions that appropriately delay hip fracture surgery. Methods We assembled a list of diagnosis and procedure codes to reflect the NICE 124 conditions. The list was reviewed and updated by an advanced clinical coder. The list was refined by five clinical experts. We then screened Canadian Institute for Health Information discharge abstracts for 153 918 patients surgically treated for a non-pathological first hip fracture between 1 January 2004 and 31 December 2012 for diagnosis codes present on admission and procedure codes that antedated hip fracture surgery. We classified abstracts as having medical reasons for delaying surgery based on the presence of these codes. Results In total, 10 237 (6.7%; 95% CI 6.5% to 6.8%) patients had diagnostic and procedure codes indicating medical reasons for delay. The most common reasons for medical delay were exacerbation of a chronic chest condition (35.9%) and acute chest infection (23.2%). The proportion of patients with reasons for medical delays increased with time from admission to surgery: 3.9% (95% CI 3.6% to 4.1%) for same day surgery; 4.7% (95% CI 4.5% to 4.8%) for surgery 1 day after admission; 7.1% (95% CI 6.9% to 7.4%) for surgery 2 days after admission; and 15.5% (95% CI 15.1% to 16.0%) for surgery more than 2 days after admission. The trend was seen for admissions on weekday working hours, weekday after hours and on weekends. Conclusion Administrative data can be considered to identify conditions that appropriately delay hip fracture surgery. Accounting for medically necessary delays can improve estimates of the effectiveness of early surgery.