Ulrich Lindemann

Effectiveness of a multifaceted intervention on falls in nursing home residents

OBJECTIVES:   To evaluate the effectiveness of a multifaceted, nonpharmaceutical intervention on incidence of falls and fallers.

Evaluation of a fall detector based on accelerometers: a pilot study

As falls and fall-related injuries remain a major challenge in the public health domain, reliable and immediate detection of falls is important so that adequate medical support can be delivered. Available home alarm systems are placed on the hip, but have several shortcomings. A fall detector based on accelerometers and placed at head level was developed, as well as an algorithm able to distinguish between activities of daily living and simulated falls. Accelerometers were integrated into a hearing-aid housing, investigation into the acceleration patterns of the head of a young volunteer during intentional falls. The specificity was assessed by investigation into activities of daily living of the same volunteer. In addition, a healthy elderly woman (83 years) wore the sensor during the day. Three trigger thresholds were identified so that a fall could be recognised: the sum-vector of acceleration in the xy-plane higher than 2 g; the sumvector of velocity of all spatial components right before the impact higher than 0.7ms−1; and the sum-vector of acceleration of all spatial components higher than 6g. The algorithm was able to discriminate activities of daily living from intentional falls. Thus high sensitivity and specificity of the algorithm could be demonstrated that was better than in other fall detectors worn at the hip or wrist at the same stage of development.

Chronic stroke survivors benefit from high-intensity aerobic treadmill exercise: a randomized control trial.

Background and objective. Ambulatory subjects after stroke may benefit from gait-oriented cardiovascular fitness training, but trials to date have not primarily assessed older persons. Methods. Thirty-eight subjects (age >60 years) with residual hemiparetic gait were enrolled >6 months after stroke. Participants were randomized to receive 3 months (3×/week) progressive graded, high-intensity aerobic treadmill exercise (TAEX) or conventional care physiotherapy. Primary outcome measures were peak exercise capacity (Vo2peak) and sustained walking capacity in 6-minute walks (6MW). Secondary measures were gait velocity in 10-m walks, Berg Balance Scale, functional leg strength (5 chair-rise), self-rated mobility (Rivermead Mobility Index), and quality of life (SF-12). Results. Thirty-six participants completed the study (18 TAEX, 18 controls). TAEX but not conventional care improved Vo2peak (difference 6.4 mL/kg/min, P < .001) and 6MW (53 m, P < .001). Likewise, maximum walking speed (0.13 m/s, P = .01), balance (P < .05), and the mental subscore of the SF-12 (P < .01) improved more after TAEX. Gains in Vo2peak correlated with the degree at which training intensity could be progressed in the individual participant (P < .01). Better walking was related to progression in treadmill velocity and training duration (P < .001). Vo2peak and 6MW performances were still higher 1 year after the end of training when compared with the baseline, although endurance walking (6MW) at 1 year was lower than immediately after training (P < .01). Conclusion. This trial demonstrates that TAEX effectively improves cardiovascular fitness and gait in persons with chronic stroke.

Effectiveness of physical training on motor performance and fall prevention in cognitively impaired older persons: a systematic review.

Hauer K, Becker C, Lindemann U, Beyer N: Effectiveness of physical training on motor performance and fall prevention in cognitively impaired older persons: A systematic review. Am J Phys Med Rehabil 2006;85:847–857. Objective:To determine whether older cognitively impaired people benefit from physical training with regard to motor performance or fall risk reduction and to critically evaluate the methodologic approach in identified randomized controlled intervention trials. Design:Published randomized controlled intervention trials from 1966 through 2004 were identified in PubMed, CINAHL, Gerolit, and the Cochrane Central Register of Controlled Trials according to predefined inclusion criteria and evaluated by two independent reviewers using a modified rating system for randomized controlled intervention trials developed by the Cochrane Library. Results:There were 11 randomized controlled intervention trials that met the predefined inclusion criteria. There was a large heterogeneity regarding methodology, sample size, type of intervention, study outcomes, and analyses. We found conflicting evidence regarding the effect of physical training on motor performance and falls in older people with cognitive impairment. However, a considerable number of the studies had methodologic limitations, which hampered the evaluation of the effectiveness of training. Conclusions:The randomized controlled intervention trials showed only limited effectiveness of physical training in patients with cognitive impairment. More studies with adequate sample size, sensitive and validated measurements, and higher specificity for the types of intervention targeting subgroups of patients with different degrees of cognitive impairment are required to give evidence-based recommendations.

Gait analysis and WOMAC are complementary in assessing functional outcome in total hip replacement

Objective: To investigate the correlation between objective and subjective evaluation of patients with total hip replacement. Design: Prospective preliminary trial comparing the Western Ontario and McMaster University questionnaire (WOMAC) and gait analysis preoperatively and three months postoperatively. Setting: A German academic orthopaedic centre specializing in total hip replacement surgery. Subjects: Seventeen patients (median age 70 years) with hip osteoarthritis. Intervention: All patients had had a primary unilateral total hip replacement. Main measures: WOMAC questionnaire to assess self-perceived health status and gait analysis to determine objective gait parameters. Results: Performance of walking as well as subjective judgement of health status improved following surgery (gait speed P = 0.0222; stride length P = 0.038; stance phase ratio P = 0.0466; WOMAC P < 0.0001). However, the correlation between gait parameters and WOMAC was poor (r = -0.27 or less). Correlation between changes of walking parameters and WOMAC was bad to good (r = 0.01 to r = -0.72). Conclusion: The WOMAC questionnaire might not reflect walking performance. The addition of gait analysis is recommended to gain objective information about the quality of gait.

Prevention of falls in nursing homes: subgroup analyses of a randomized fall prevention trial.

OBJECTIVES: To evaluate the effectiveness of a multifactorial fall prevention program in prespecified subgroups of nursing home residents.

Automated approach for quantifying the repeated sit-to-stand using one body fixed sensor in young and older adults

Much is known about the sit-to-stand (STS) and its biomechanics. Currently, however, there is little opportunity for instrumented quantification of the STS as part of screening or diagnosis in clinical practice. The objectives of the present study were to describe the feasibility of using an automated approach for quantifying the STS using one sensor location and to start testing the discriminative validity of this approach by comparing older and younger adults. 15 older subjects recruited from a residential care home and 16 young adults performed 5 repeated sit-to-stand and stand-to-sit movements. They were instrumented with a small and lightweight measurement system (DynaPort(®)) containing 1 triaxial seismic accelerometer and 3 uniaxial gyroscopes fixed in a belt around the waist. Durations of the (sub-)phases of the STS were analyzed and maximum angular velocities were determined. All successful STS cycles were automatically detected without any errors. The STS duration in the older adults was significantly longer and more variable in all phases (i.e., sit-to-stand, standing, stand-to-sit and sitting) compared to the young adults. Older adults also exhibited lower trunk flexion angular velocity. The results of this first fully automated analysis of instrumented repeated STS movements demonstrate that several STS parameters can be identified that provide a basis for a more precise, quantitative study of STS performance in clinical practice.

Sit-stand and stand-sit transitions in older adults and patients with Parkinson's disease: event detection based on motion sensors versus force plates.

BackgroundMotion sensors offer the possibility to obtain spatiotemporal measures of mobility-related activities such as sit-stand and stand-sit transitions. However, the application of new sensor-based methods for assessing sit-stand-sit performance requires the detection of crucial events such as seat on/off in the sensor-based data. Therefore, the aim of this study was to evaluate the agreement of detecting sit-stand and stand-sit events based on a novel body-fixed-sensor method with a force-plate based analysis.MethodsTwelve older adults and 10 patients with mild to moderate Parkinson’s disease with mean age of 70 years performed sit-stand-sit movements while trunk movements were measured with a sensor-unit at vertebrae L2-L4 and reaction forces were measured with separate force plates below the feet and chair. Movement onsets and ends were determined. In addition, seat off and seat on were determined based on forces acting on the chair. Data analysis focused on the agreement of the timing of sit-stand and stand-sit events as detected by the two methods.ResultsFor the start and end of standing-up, only small delays existed for the start of forward trunk rotation and end of backward trunk rotation compared to movement onset/end as detected in the force-plate data. The end of forward trunk rotation had a small and consistent delay compared to seat off, whereas during sitting-down, the end of forward trunk rotation occurred earlier in relation to seat on. In detecting the end of sitting-down, backward trunk rotation ended after reaching the minimum in the below-feet vertical force signal. Since only small time differences existed between the two methods for detecting the start of sitting-down, longer movement durations were found for the sensor-based method. Relative agreement between the two methods in assessing movement duration was high (i.e. ICCs ≥ 0.75), except for duration of standing-up in the Parkinson’s patients (ICC = 0.61).ConclusionsThis study demonstrated high agreement of body-fixed-sensor based detection of sit-stand and stand-sit events with that based on force plates in older adults and patients with mild to moderate Parkinson’s disease. Further development and testing is needed to establish reliability for unstandardized performance in clinical and home settings.

Reduction of Femoral Fractures in Long-Term Care Facilities: The Bavarian Fracture Prevention Study

Background Hip fractures are a major public health burden. In industrialized countries about 20% of all femoral fractures occur in care dependent persons living in nursing care and assisted living facilities. Preventive strategies for these groups are needed as the access to medical services differs from independent home dwelling older persons at risk of osteoporotic fractures. It was the objective of the study to evaluate the effect of a fall and fracture prevention program on the incidence of femoral fracture in nursing homes in Bavaria, Germany. Methods In a translational intervention study a fall prevention program was introduced in 256 nursing homes with 13,653 residents. The control group consisted of 893 nursing homes with 31,668 residents. The intervention consisted of staff education on fall and fracture prevention strategies, progressive strength and balance training, and on institutional advice on environmental adaptations. Incident femoral fractures served as outcome measure. Results In the years before the intervention risk of a femoral fracture did not differ between the intervention group (IG) and control group (CG). During the one-year intervention period femoral fracture rates were 33.6 (IG) and 41.0/1000 person years (CG), respectively. The adjusted relative risk of a femoral fracture was 0.82 (95% CI 0.72-0.93) in residents exposed to the fall and fracture prevention program compared to residents from CG. Conclusions The state-wide dissemination of a multi-factorial fall and fracture prevention program was able to reduce femoral fractures in residents of nursing homes.

Maximum step length as a potential screening tool for falls in non-disabled older adults living in the community

Background and aims: Identification of the risk of falls in a cohort of interest is a prerequisite for a targeted fall prevention study. Motor tasks are widely used as baseline assessment in such studies, but there are only a few well-evaluated tests of motor performance to predict falls prospectively. This study was conducted to find out if the potential of the maximum step length (MSL) test can predict future falls in non-disabled older persons. Methods: A modified version of the MSL test was used for baseline assessment in 56 community-dwelling, non-disabled elderly persons (mean age 67.7 yrs, SD 6 yrs; 57% women). During a follow-up of 1 year, falls were recorded in a daily calendar. Results: During the follow-up, 30 persons (54%) fell, with no gender difference in reporting of falls between men and women. The adjusted mean valid step length and adjusted maximum valid step length were predictive of future falls with a sensitivity/specificity of 77%/62% and 70%/69%, respectively. Combining MSL test results with fall history increased sensitivity to 93% and 90%, respectively, but decreased specificity to 54% and 58%, respectively. Conclusions: The MSL test is a feasible tool, with low requirements in space, predicting future falls in community-dwelling older persons. In combination with history of falls, the sensitivity of the test increased considerably.