Benjamin Steinhilber

Feasibility and efficacy of an 8-week progressive home-based strengthening exercise program in patients with osteoarthritis of the hip and/or total hip joint replacement: a preliminary trial

The feasibility and efficacy of an additional progressive home-based strengthening exercise program (PHSEP) on subjects that already attended supervised institutional exercise therapy was investigated. Thirty-six hip patients with hip osteoarthritis (OA) and/or total hip replacement in at least one hip joint were randomly assigned to an intervention group (IG) or a control group (CG). IG (18 patients, mean age 64.9, standard deviation (SD) 7.5) followed an 8-week PHSEP in addition to their weekly institutional exercise therapy, while CG (18 patients, mean age 64.7, SD 9) solely continued the weekly institutional exercise sessions. Before and after the intervention period, strength of hip muscles was quantified applying isokinetic concentric and isometric measurements, and health-related quality of life was monitored using the SF36 questionnaire. Adherence to the exercise program was evaluated using exercise logs. The PHSEP was feasible for all subjects in IG with an adherence of 99%. Exercise logs reported that pain resulting from the PHSEP was low. Increased strength in isokinetic concentric hip adduction (13%) and isometric hip abduction (9%), adduction (12%), and flexion (7%) was found in IG in comparison to CG. The results of the SF36 did not change during the intervention period. Consequently, supervised institutional exercise therapy supplemented by a PHSEP could increase hip muscle strength in patients with hip OA and/or total hip replacement. However, further research should evaluate the optimal frequency and duration of such supplementary sessions and their potential to increase physical function and reduce pain.

Development of an arm support system to improve ergonomics in laparoscopic surgery: study design and provisional results.

BackgroundLaparoscopic surgery (LS) induces physical stress to the surgeon that is associated with an increased prevalence of musculoskeletal pain and injury in the shoulder–neck region. The aim of this research project is to develop an arm support system (ASsyst) that reduces physical stress and is applicable to various laparoscopic interventions and operation room settings.MethodsA systematic approach to develop an ASsyst started in October 2012 consisting of five consecutive steps. In step 1, 14 laparoscopic interventions were observed using subjective and objective measures to determine key indicators for the conception of an ASsyst in LS. In step 2, an expert workshop was held to find and evaluate solutions to generate concepts for a support system based on the results of step 1 and general methods. During the third step, prototypes of ASsyst were tested in an experimental setting. Steps 4 and 5 are currently in process and include the final development of the ASsyst using the most promising concept for the evaluation during simulated LS.ResultsIncreased levels of physical stress were found in LS. Asymmetric strains were common. Three prototypes of ASsyst emerged from step 1 and 2. These prototypes were a cable construction with a noose for the lower arm, a support from below the elbow and a pneumatic vest supporting the upper arm. The experimental testing of these prototypes demonstrated reduced physical stress when compared to the unsupported environment. The support from below the elbow seemed to be the most practical in terms of implementation in various operation room settings and acceptance by surgeons. Step 4 and 5 are still in process.ConclusionsErgonomic problems have been identified in LS that could be addressed by an ASsyst. The concept of supporting the elbow from below has been found to be the most promising approach.

Reproducibility of concentric isokinetic and isometric strength measurements at the hip in patients with hip osteoarthritis: A preliminary study

To determine the reproducibility of isokinetic and isometric hip flexion, extension, abduction and adduction strengt h scores in patients with hip osteoarthritis (N = 16) and healthy subjects, testing was conducted twice 7 days apart. The patient group (PG) consisted of 16 subjects with unilateral or bilat eral osteoarthritis of the hip (11 women, 5 men; age 56-75y). The control group (CG) included 13 age-matched healthy subjects (9 women, 4 men; age 54-73y). The standard error of measurement (SEM) served as the reproducibility outcome parameter. The highest SEM values were obtained for hip extension measurements (15.4-16.7 Nm), followed by hip adduction (7.9-11.8 Nm) and hip flexion measurements (5.2-7.5 Nm). The smallest values were quantified for hip abduction measurements (4.7-7 .7 Nm). PG showed larger values in all isometric measures except for hip extension and isokinetic hip abduction. When the 95% confidence interval is incorporated, these SEMs become sign ificant. Thus clinicians should be aware of the large measurement error in patients with hip OA. Adequate preparations and firm fixa tion of the pelvis are key elements to achieve reproducible results.

Stiffness, Pain, and Hip Muscle Strength Are Factors Associated With Self-reported Physical Disability in Hip Osteoarthritis

Background:Physical disability (PD) is common among patients with osteoarthritis (OA) of the hip. Exercise therapy is proposed to be a potential intervention to reduce PD. However, the optimal targets of an exercise program are not known. Purpose:The aim of the present study was to identify factors that explain the level of self-reported PD in patients with hip OA. Knowledge of these factors will help develop specific and effective exercise programs. Methods:Data from 149 patients with hip OA (85 men and 64 women) were analyzed. Self-reported PD was quantified using the physical function subscale of the Western Ontario and McMaster index. A stepwise regression analysis was conducted to identify significant factors associated with self-reported PD. Results:Stiffness, pain, and hip muscle strength were found to be significant factors related to the level of self-reported PD in hip OA. These factors explained 59% (r2 adjusted = 0.59) of the variance. Body mass index, gender, age, and passive internal hip rotation and flexion range of motion explained only minor parts of the dependent variable self-reported PD. Discussion and Conclusion:Stiffness, pain, and hip muscle strength are associated with self-reported PD in hip OA. It is imperative that exercise treatments for hip OA include strategies to modify these factors. Further research should evaluate their role in preventing hip OA.

Long-Lasting Changes in Muscle Twitch Force During Simulated Work While Standing or Walking:

Objective: The aim of this study was to evaluate the long-lasting effects of prolonged standing work on a hard floor or floor mat and slow-pace walking on muscle twitch force (MTF) elicited by electrical stimulation. Background: Prolonged standing work may alter lower-leg muscle function, which can be quantified by changes in the MTF amplitude and duration related to muscle fatigue. Ergonomic interventions have been proposed to mitigate fatigue and discomfort; however, their influences remain controversial. Method: Ten men and eight women simulated standing work in 320-min experiments with three conditions: standing on a hard floor or an antifatigue mat and walking on a treadmill, each including three seated rest breaks. MTF in the gastrocnemius-soleus muscles was evaluated through changes in signal amplitude and duration. Results: The significant decrease of MTF amplitude and an increase of duration after standing work on a hard floor and on a mat persisted beyond 1 hr postwork. During walking, significant MTF metrics changes appeared 30 min postwork. MTF amplitude decrease was not significant after the first 110 min in any of the conditions; however, MTF duration was significantly higher than baseline in the standing conditions. Conclusion: Similar long-lasting weakening of MTF was induced by standing on a hard floor and on an antifatigue mat. However, walking partially attenuated this phenomenon. Application: Mostly static standing is likely to contribute to alterations of MTF in lower-leg muscles and potentially to musculoskeletal disorders regardless of the flooring characteristics. Occupational activities including slow-pace walking may reduce such deterioration in muscle function.

Analysis and Comparison of Ergonomics in Laparoscopic and Open Surgery – A Pilot Study

This pilot study systematically analyses and compares ergonomics of laparoscopic and open surgery in gynecology and urology. The results will help to identify and describe elements for ergonomic optimization in these professions. Further a supporting technical system to reduce physical demands shall be developed on the basis of assessment. A multiple measurement approach including subjective and objective methods was used with regard to the complex setting in surgery units. Subjective and objective methods indicate musculoskeletal strain for both types of surgery. Several indications for low ergonomics and static work have been found.

Exercise therapy in patients with hip osteoarthritis: Effect on hip muscle strength and safety aspects of exercise—results of a randomized controlled trial

Abstract Purpose: To evaluate the effect of an exercise therapy concept (the Tübingen exercise therapy approach THüKo) for increasing hip muscle strength (HMS) in patients with hip osteoarthritis (OA), and to investigate whether patients do adhere to the intervention and if there are any adverse events related to the intervention. Methods: A total of 210 hip OA patients (89 females, 121 males) were randomized into a 12-week exercise intervention (THüKo) including group sessions (1/week) and home exercising (2/week), a placebo ultrasound group (1/week) or a control group (no treatment). HMS was measured as isometric peak torque of hip abduction, adduction, flexion, and extension. Adherence to exercise and safety aspects were monitored as additional outcomes. Results: Baseline adjusted post intervention HMS of the THüKo group were higher compared to the control group (differences of 0.11–0.27 Nm/kg, p < 0.01) and to the placebo ultrasound group (differences of 0.09–0.19 Nm/kg, p < 0.01). Adherence to exercise was high (about 90%). No subject had to refuse from training because of an exercise related adverse event and exercise related pain was only of intermittent nature without sustainable adverse effects. Conclusions: The Tübingen exercise therapy approach has shown to have a significant positive effect on HMS. Its implementation has shown to be feasible and safe according to the percentage of exercise participation and the absence of sustainable adverse events.

Ergonomic Benefits From a Laparoscopic Instrument With Rotatable Handle Piece Depend on the Area of the Operating Field and Working Height

Objective To evaluate the effect of a laparoscopic instrument with a 360° rotatable handle piece (rot-HP) on biomechanical stress and precision in different areas of a simulated operating field at two working heights. Background Surgeons performing laparoscopic procedures are exposed to biomechanical stress and have an increased risk of musculoskeletal complaints. Method Fifty-seven healthy subjects (27 men, median age 26) without experience in laparoscopy performed a precision task in four quadrants (A–D) of the operating field using the rot-HP or a common fixed handle piece (fixed-HP) at an individually adjusted lower or higher working height. Biomechanical stress was assessed by surface EMG, wrist joint angles, and arm postures and precision by the number of mistakes. Results Using the rot-HP reduced muscle activity of the biceps brachii and flexor carpi radialis muscle. An interaction of flexor activity and area of the operating field occurred with the lowest activity in Quadrant C. Wrist joint angles were more neutral using the rot-HP, especially when the lower working height was applied and in Quadrants B and C. However, increased wrist dorsal flexion occurred in Quadrant A while using the rot-HP. Arm postures and precision were less affected. Conclusion The rot-HP allows some reductions of stresses in the arm and hand region, whereas the stress in the shoulder neck region is not modified. Application The instrument’s position and the working height may have to be considered as mediatory factors when describing the effectiveness of an ergonomic handle design for laparoscopic instruments.

893 Reduction of leg swelling by compression stockings with different compression intensities during a two hour standing exposure – a pilot study

Introduction Lower leg swelling is considered to be a risk factor of venous disorders among workers exposed to prolonged standing. Compression stockings might be effective in reducing lower leg swelling; however, little is known about the effect of different compression intensities. The aim of this study was to investigate the influence of two different compression intensities throughout a 2 hour standing exposure on lower leg swelling, complaints, and wearing comfort. Methods 40 healthy subjects participated in this randomised cross-over experiment with three 2 hour standing exposures that were tested on separate days. In condition A, subjects did not wear compression stockings; in condition B and C, subjects wore compression stockings medical class I (18–21 mmHg) and class II (23–32 mmHg), respectively. Lower leg swelling was quantified by measures of lower leg volume (water plethysmography) and bioelectrical impedance before and after each standing exposure. Level of discomfort was assessed every 30 min (11-point Likert-Scale) and wearing comfort was measured at the end of the exposure using a custom-made standardised questionnaire. The study was approved by the ethics committee of the University of Tuebingen. Result Preliminary results (n=19) indicated that wearing compression stockings reduced lower leg swelling compared to wearing no stockings, but there was no difference in leg swelling between the two compression classes. Levels of discomfort were rather low and did not significantly differ across conditions. Higher levels of wearing comfort were found for the class I compared to the class II stockings. Discussion These preliminary results suggest that in healthy subjects the lower compression intensity might be as effective as the higher intensity in reducing lower leg swelling. This is an important finding since compliance of wearing compression stockings increases with lower compression intensities, which is supported by the increased wearing comfort for the lower compression class in this study.

Intra- and inter-rater reliability of lower leg waterplethysmography, bioelectrical impedance and muscle twitch force for the use in standing work evaluation.

OBJECTIVES Prolonged standing is associated with multiple risk factors for musculoskeletal and venous disorders. In Germany over 50% of the working population spend most of their working time in a standing position. Basic understanding of prolonged standing physiology is lacking. We therefore plan to investigate the influence of 5 h standing (including breaks) on lower limb oedema measured by waterplethysmography (WP) and bioelectrical impedance (BI) and fatigue in the triceps surae muscle using muscle twitch force (MTF). In order to interpret our results, test-retest and inter-rater reliability of these measurement methods was evaluated first. APPROACH 20 subjects (9 female) were included to test each method three times (M1, M2, M3) in 30 min periods with two raters (R1, R2) on separate days. Intraclass correlation coefficient (ICC; 2,1), standard error of measurement (SEM) and smallest real difference (SRD) were calculated for both raters. MAIN RESULTS The SEM and SRD calculated for WP were 27 and 75 ml, respectively, for R1 and 23 and 64 ml, respectively, for R2 with an ICC of 0.98 (p  <  0.0001). Statistically significant mean differences between M1 and M2 (R1  =  23 ml, p  =  0.004; R2  =  19 ml, p  =  0.027) but not significant mean differences between M2 and M3 (R1  =  -6 ml, p  =  0.45; R2  =  4 ml, p  =  0.27) were calculated for both raters. BI data revealed SEM and SRD values of 3.8 and 10.5 Ω, respectively, for R1 and 3.4 and 9.4 Ω, respectively, for R2 with an ICC of 0.24 (p  =  0.001). The differences between M1 and M2 (R1  =  3.9 Ω, p  =  0.0001; R2  =  2.4 Ω, p  =  0.049) and between M2 and M3 (R1  =  2.3 Ω, p  =  0.012; R2  =  2.0 Ω, p  =  0.008) were found to be statistically significant for both raters. SEM and SRD for MTF were 0.19 and 0.53 N, respectively, for R1 and 0.23 and 0.64 N, respectively, for R2 with an ICC of 0.71 (p  <  0.0001). Mean differences between M1 and M2 were statistically significant for rater 1 but not for rater 2 (R1  =  0.13 N, p  =  0.022; R2  =  0.12 N, p  =  0.082) and the same was found for the difference between M2 and M3 for both raters (R1  =  0.04 N, p  =  0.37; R2  =  0.08 N, p  =  0.12). SIGNIFICANCE All three measurement methods showed good reliability and should be suitable for detecting effects of standing work on oedema development and fatigue as seen in previous results of long term standing experiments. Inter-rater reliability is found to be satisfactory as well, demonstrated by the small differences in SEM values of R1 and R2. Statistically significant differences shown for all three measurement methods could be due to lacking standardisation of leg placement and thus an actual lower leg volume change between measurements, indicating possibilities for further improvement of SEM values.