Prediction of Postoperative Ambulatory Status 1 Year After Hip Fracture Surgery

Hirose J, Ide J, Yakushiji T, Abe Y, Nishida K, Maeda S, Anraku Y, Usuku K, Mizuta H. Prediction of postoperative ambulatory status 1 year after hip fracture surgery.

Objectives

To assess the validity of Estimation of Physiologic Ability and Surgical Stress (E-PASS) for predicting the postoperative risk and ambulatory status long-term follow-up after hip fracture surgery and to establish an algorithm for predicting their ambulatory status.

Design

Cohort study.

Setting

Twelve hospitals belonging to the regional network for hip fracture in Japan.

Participants

The study population was composed of 421 patients; 268 underwent surgery between April 2004 and March 2006 (group A), and 153 were treated surgically between April 2006 and March 2007 (group B). All were operated at 3 surgical hospitals and, subsequently, transferred to 9 rehabilitation centers.

Interventions

Not applicable.

Main Outcome Measures

We evaluated various factors, including their E-PASS scores to determine whether there was a correlation with the patients' mortality rate and their ability to walk at discharge and 1 year after surgery (group A). Using multiple regression analysis, we then developed algorithms to predict the ability of elderly patients to walk after hip fracture surgery. We applied the algorithms to group B patients and compared their actual and predicted ambulatory status.

Results

In group A patients, the postoperative walking ability and mortality rate were highly correlated with their E-PASS scores and dementia status. In group B, our algorithms exhibited good correlations between the predicted and actual walking ability at both time points (ρ=0.6, P<.001).

Conclusions

In candidates for hip fracture surgery, the E-PASS scores exhibited a good correlation with the patients' functional and survival prognoses, and the algorithm including E-PASS scores and dementia status can accurately estimate the ambulatory status at discharge and 1 year after surgery.     

The impact of home-based physiotherapy interventions on breathlessness during activities of daily living in severe COPD: A systematic review

Objectives

To conduct a systematic review and meta-analysis to determine the impact of home-based physiotherapy interventions on breathlessness during activities of daily living (ADL) in severe chronic obstructive disease (COPD).

Data sources

The electronic databases AMED, CINAHL, Cochrane Central Register of Controlled Trials, Embase, Medline and Physiotherapy Evidence Database (PEDro) were searched from their inception to Week 20 2008. Bibliographies of all potentially relevant retrieved studies, identified relevant systematic reviews and international guidelines were searched by hand.

Review methods

Inclusion criteria consisted of individuals over 18 years of age with severe COPD (defined as forced expiratory volume in 1 second ≤50% predicted) without cardiovascular co-morbidities, home-based interventions and valid, reliable breathlessness ADL outcome measures. The PEDro scale assessed methodological quality. Data extraction included baseline characteristics, treatment intervention, frequency of training, level of supervision, breathlessness ADL outcome measure and results. Where possible, a random-effects meta-analysis was applied to appropriate trial data to produce overall quantitative results.

Results

Seven studies, providing nine data sets, met the inclusion criteria. Trial PEDro scores ranged from 4 to 7 out of 10. Studies were homogenous at baseline regarding age and COPD severity, although subjects were predominantly male. Five studies investigated inspiratory or expiratory muscle training, and two studies investigated exercises. Statistically significant breathlessness ADL outcome improvements were reported for all interventions except expiratory muscle training. Five studies demonstrated clinical significance (four for inspiratory muscle training and one for exercise). However, due to heterogeneity among study interventions and outcomes, meta-analysis was only considered clinically appropriate on one occasion to pool three inspiratory muscle training studies in relation to breathlessness score. The random-effects meta-analysis indicated that, on average, inspiratory muscle training improved the breathlessness score significantly by 2.36 (95% confidence interval 0.76 to 3.96) compared with controls.

Conclusion

Inspiratory muscle training and exercise are home-based physiotherapy interventions that may improve breathlessness during ADL in severe COPD. Administration can only be advocated tentatively in outpatient services and primary care at this stage because further higher quality, more homogeneous research with larger sample sizes is required to substantiate the current findings.     

How Reproducible Is Home-Based 24-Hour Ambulatory Monitoring of Motor Activity in Patients With Multiple Sclerosis?

Rietberg MB, van Wegen EE, Uitdehaag BM, de Vet HC, Kwakkel G. How reproducible is home-based 24-hour ambulatory monitoring of motor activity in patients with multiple sclerosis?

Objective

To determine the reproducibility of 24-hour monitoring of motor activity in patients with multiple sclerosis (MS).

Design

Test-retest design; 6 research assistants visited the participants twice within 1 week in the home situation.

Setting

General community.

Participants

A convenience sample of ambulatory patients (N=43; mean age ± SD, 48.7±7.0y; 30 women; median Expanded Disability Status Scale scores, 3.5; interquartile range, 2.5) were recruited from the outpatient clinic of a university medical center.

Interventions

Not applicable.

Main Outcome Measures

Dynamic activity and static activity parameters were recorded by using a portable data logger and classified continuously for 24 hours. Reproducibility was determined by calculating intraclass correlation coefficients (ICCs) for test-retest reliability and by applying the Bland-Altman method for agreement between the 2 measurements. The smallest detectable change (SDC) was calculated based on the standard error of measurement.

Results

Test-retest reliability expressed by the ICC_agreement was .72 for dynamic activity, .74 for transitions, .77 for walking, .71 for static activity, .67 for sitting, .62 for standing, and .55 for lying. Bland and Altman analysis indicated no systematic differences between the first and second assessment for dynamic and static activity. Measurement error expressed by the SDC was 1.23 for dynamic activity, 66 for transitions, .99 for walking, 1.52 for static activity, 4.68 for lying, 3.95 for sitting, and 3.34 for standing.

Conclusions

The current study shows that with 24-hour monitoring, a reproducible estimate of physical activity can be obtained in ambulatory patients with MS.     

Age-related differences in Tai Chi gait kinematics and leg muscle electromyography: a pilot study

Wu G. Age-related differences in Tai Chi gait kinematics and leg muscle electromyography: a pilot study.

Objective

To compare the biomechanic features of Tai Chi gait by elders with those by young adults, and with those of normative gait.

Design

Cross-sectional study.

Setting

Laboratory-based testing.

Participants

Young (n=6; 3 women) and old (n=6; 5 women) Tai Chi practitioners.

Intervention

All subjects had practiced Tai Chi for at least 4 months.

Main Outcome Measures

Spatial, temporal, and leg muscle electromyography during Tai Chi gait and normative gait.

Results

The primary age-related differences in Tai Chi gait were during single stance, with elders having significantly shorter single-stance time (−50%), less lateral displacement (-30%), knee flexion (-42%), hip flexion (-39%), activation time in the tibialis anterior (-13%), soleus (-39%), and tensor fascia lata (TFL) (-21%), activation magnitude in the tibialis anterior (-39%), and coactivation time of the tibialis anterior and soleus (-47%). Compared with normative gait, elders during Tai Chi gait had significantly larger knee (139%) and hip (66%) flexions, longer duration (90%-170%) and higher magnitude (200%-400%) of the tibialis anterior, rectus femoris, and TFL muscle activities, and longer duration of coactivation of most leg muscle pairs (130%-380%).

Conclusions

The elders practice Tai Chi gait in higher posture than younger subjects. The Tai Chi gait poses significantly higher challenges to elder’s balance and muscular system than does their normative gait.     

The effects of Pilates training on flexibility and body composition: an observational study

Segal NA, Hein J, Basford JR. The effects of Pilates training on flexibility and body composition: an observational study. Arch Phys Med Rehabil 2004;85:1977-81.

Objective

To assess claims regarding the effects of Pilates training on flexibility, body composition, and health status.

Design

An observational prospective study.

Setting

A community athletic club.

Participants

A sample of 47 adults (45 women, 2 men) who presented for Pilates training.

Interventions

Not applicable.

Main outcome measures

Fingertip-to-floor distance, truncal lean body mass by bioelectric impedance, health status by questionnaire and visual analog scale were assessed at baseline, 2, 4, and 6 months (±1wk).

Results

Thirty-two of 47 enrolled subjects met the protocol requirements of missing no more than 1 weekly 1-hour session Pilates mat class during each 2-month period. Investigators were blinded to measurements from previous time points. Median (interquartile range [IQR]) fingertip-to-floor distance improved from baseline by 3.4cm (1.3-5.7cm), 3.3cm (0.3- 7.8cm), and 4.3cm (1.5-7.6cm) at 2, 4, and 6 months, respectively (paired nonparametric analysis, all P<.01). There were no statistically significant changes in truncal lean body mass, height, weight, or other body composition parameters. Self-assessment of health also did not change in a statistically significant manner from its baseline median (IQR) value of 77mm (69-85mm).

Conclusions

Pilates training may result in improved flexibility. However, its effects on body composition, health status, and posture are more limited and may be difficult to establish. Further study might involve larger sample sizes, comparison with an appropriate control group, and assessment of motor unit recruitment as well as strength of truncal stabilizers.     

Relationship Between the Western Ontario and McMaster Universities Osteoarthritis Index Physical Function Subscale and Physical Performance Measures in Patients With Hip Osteoarthritis

Wright AA, Cook CE, Baxter GD, Garcia J, Abbott JH. Relationship between the Western Ontario and McMaster Universities Osteoarthritis Index Physical Function Subscale and physical performance measures in patients with hip osteoarthritis.

Objective

To examine the convergent and factor validity of the Western Ontario and McMaster Universities Osteoarthritis Index physical function subscale (WOMAC-PF) using a battery of physical performance measures (PPMs) in patients with non-end-stage hip osteoarthritis (OA).

Design

Cross-sectional data.

Setting

A university physiotherapy research center.

Participants

Patients with a clinical diagnosis of hip OA (N=93) referred for participation in research.

Interventions

Not applicable.

Main Outcome Measures

Factor validity of the WOMAC-PF was evaluated by using confirmatory factor analysis (CFA). Exploratory factor analysis (EFA) was run to determine whether WOMAC-PF and PPMs were capturing separate aspects of physical function. Covariates including pain, depression, Pain Beliefs Screening Instrument, body mass index, hip flexion, use of an assistive device, and lower-extremity strength were included in the EFA as independent variables.

Results

CFA of the WOMAC-PF yielded a 1-factor solution accounting for 84% of the variance in the data (eigenvalue=11). EFA yielded a 2-factor solution accounting for 68% of the variance in the data. The PPMs and the WOMAC-PF loaded on separate factors.

Conclusions

We were unable to confirm a 4-factor solution model of the WOMAC-PF as previously reported. This suggests that the WOMAC-PF shows sufficient factor validity in capturing perceived physical function in patients with non-end-stage hip OA but captures a different construct than that of PPMs, confirming the need for both when evaluating functional outcome. Furthermore, we suggest a new standardized battery of physical performance measures to serve as the criterion standard against which self-report measures could be compared.     

Asymptomatic median mononeuropathy among men with chronic paraplegia

Liang H-W, Wang Y-H, Pan S-L, Wang TG, Huang T-S. Asymptomatic median mononeuropathy among men with chronic paraplegia.

Objectives

To compare electrophysiologic abnormalities of the median nerve in asymptomatic paraplegic subjects and able-bodied controls and to examine the influence of personal factors on these parameters.

Design

Cross-sectional survey.

Setting

University hospital.

Participants

Forty-seven men with paraplegia and 36 able-bodied controls underwent nerve conduction studies on both upper limbs. All were free of hand numbness in the past month, diabetic mellitus, or neuromusculoskeletal injuries to the upper limbs.

Interventions

Not applicable.

Main Outcome Measure

Nerve conduction studies of the bilateral median and ulnar nerves.

Results

Although the 2 groups were of comparable age and had a similar body mass index (BMI), the subjects with paraplegia had a significantly higher proportion of asymptomatic median mononeuropathy than the controls (25.5% vs 5.6%, P=.02). The spinal cord injury (SCI) group had a prolonged median distal latency and a slowed digit-wrist sensory nerve conduction velocity. Multivariate general linear model analysis showed that prolonged motor and sensory latencies of the median nerve were associated with the SCI group and with greater BMI.

Conclusions

The asymptomatic subjects with paraplegia had a significantly higher frequency of median mononeuropathy than the able-bodied controls. There was also an association between BMI and distal latency of the median nerve.     

Psychologic Factors and Risk of Mortality After Spinal Cord Injury

Krause JS, Carter R, Zhai Y, Reed K. Psychologic factors and risk of mortality after spinal cord injury.

Objective

To identify the association of 2 distinct psychologic constructs, personality and purpose in life (PIL), with risk of early mortality among persons with spinal cord injury (SCI).

Design

Prospective cohort study with health data collected in late 1997 and early 1998 and mortality status ascertained in December 2005.

Setting

A large rehabilitation hospital in the southeastern United States.

Participants

Adults (N=1386) with traumatic SCI, at least 1 year postinjury.

Interventions

Not applicable.

Main Outcome Measures

We first evaluated the significance of a single psychologic predictor (a total of 6 scales) while controlling for biographic and injury predictors using Cox proportional hazards modeling and subsequently built a comprehensive model based on an optimal group of psychologic variables.

Results

There were a total of 224 (16.2%) observed deaths in the full sample. The total number of deaths was reduced to 164 in the final statistical model (of 1128 participants) because of missing data. All 6 psychologic factors were statistically significant in the model that was adjusted for biographic and injury factors, whereas only 3 psychologic factors were retained in the final comprehensive model, including 2 personality scales (Impulsive Sensation Seeking, Neuroticism-Anxiety) and the PIL scale. The final comprehensive model only modestly improved the overall prediction of survival compared with the model with only biographic and injury variables, because the pseudo-R² increased from 0.121 to 0.129, and the concordance increased from 0.730 to 0.747.

Conclusions

The results affirm the importance of psychologic factors in relation to survival after SCI.     

Impact of a multifaceted community-based falls prevention program on balance-related psychologic factors

Filiatrault J, Gauvin L, Richard L, Robitaille Y, Laforest S, Fournier M, Corriveau H. Impact of a multifaceted community-based falls prevention program on balance-related psychologic factors.

Objective

To assess the impact of a multifaceted falls prevention program including exercise and educational components on perceived balance and balance confidence among community-dwelling seniors.

Design

Quasi-experimental design.

Setting

Community-based organizations.

Participants

Two hundred community-dwelling adults aged 60 years and over recruited by community-based organizations.

Intervention

A 12-week multifaceted falls prevention program including 3 components (a 1-hour group exercise class held twice a week, a 30-minute home exercise module to be performed at least once a week, a 30-minute educational class held once a week).

Main Outcome Measures

Perceived balance and balance confidence.

Results

Multivariate analysis showed that the program was successful in increasing perceived balance in experimental participants. However, balance confidence was not improved by program participation.

Conclusions

A multifaceted community-based falls prevention program that was successful in improving balance performance among community-dwelling seniors also had a positive impact on perceived balance. However, the program did not improve participants' balance confidence. These results suggest that balance confidence has determinants other than balance and that new components and/or modifications of existing components of the program are required to achieve maximal benefits for seniors in terms of physical and psychologic outcomes.     

Use of the Continuous Scale Physical Functional Performance Test in Stroke Survivors

Manns PJ, Tomczak CR, Jelani A, Cress ME, Haennel R. Use of the continuous scale physical functional performance test in stroke survivors.

Objective

To (1) determine the feasibility of the continuous scale physical functional performance 10-item test (CS-PFP10) for the measurement of physical function in stroke survivors, (2) characterize physical functional performance of stroke survivors and their matched controls, and (3) explore the associations among physical functional performance, ambulatory activity, and peak oxygen uptake (Vo₂peak).

Design

Case control.

Setting

University research setting.

Participants

Ten participants with stroke and 10 healthy controls matched for age, sex, and physical activity.

Interventions

Not applicable.

Main Outcome Measures

The CS-PFP10 test was used to measure functional ability. The test requires performance of 10 serial tasks that range from low to high difficulty. The step activity monitor was used to measure absolute ambulatory activity and was reported as the average number of steps a day over a 4-day period. Vo₂peak was determined using a metabolic cart and a recumbent cycle ergometer.

Results

Stroke survivors scored lower than healthy controls on all individual tasks, domains, and the total score on the CS-PFP10. Higher Vo₂peak was associated with higher total scores on the CS-PFP10 in both stroke survivors and controls. In stroke survivors, lower levels of impairment (as indicated by the Chedoke-McMaster stroke assessment) were associated with higher total CS-PFP10 scores.

Conclusions

The CS-PFP10 is a measure of physical performance that is feasible to use with ambulatory participants with stroke. Future investigations with people with stroke should explore the ability of the CS-PFP10 to provide meaningful information about change in CS-PFP10 subscales with interventions that target items on the subscales, such as balance or upper extremity strength.     

Disparities in Utilization of Outpatient Rehabilitative Care Following Hip Fracture Hospitalization With Respect to Race and Ethnicity

Nguyen-Oghalai TU, Ottenbacher KJ, Kuo Y-F, Wu H, Grecula M, Eschbach K, Goodwin JS. Disparities in utilization of outpatient rehabilitative care following hip fracture hospitalization with respect to race and ethnicity.

Objective

To compare the prevalence of discharge home to self-care after hip fracture hospitalization among the elderly in 3 racial groups: whites, Hispanics, and blacks.

Design

Secondary data analysis.

Setting

US hospitals.

Participants

Patients (N=34,203) aged 65 and older with Medicare insurance discharged after hip fracture hospitalization between 2001 and 2005.

Interventions

Not applicable.

Main Outcome Measure

Discharge home to self-care.

Results

Bivariate analyses showed higher rates of discharge home to self-care among minorities, 16.4% for Hispanics, 8.7% for blacks, and 5.9% for whites. Hispanics had 3-fold higher odds of being discharged home to self-care, and blacks had about 50% higher odds of being discharged home to self-care after adjusting for age, sex, Klabunde's comorbidity index, income, year of admission, type of hip fracture, surgical stabilization procedure, and length of hospital stay.

Conclusions

The higher rate of discharge home to self-care among minorities underscores the risk of suboptimal outpatient rehabilitative care among minorities with hip fracture.     

Systematic Review of Hip Fracture Rehabilitation Practices in the Elderly

Chudyk AM, Jutai JW, Petrella RJ, Speechley M. Systematic review of hip fracture rehabilitation practices in the elderly.

Objective

To address the need for a research synthesis on the effectiveness of the full range of hip fracture rehabilitation interventions for older adults and make evidence based conclusions.

Data Sources

Medline, PubMed, EMBASE, CINAHL, and the Cochrane Central Register of Controlled Trials were searched from 1980 to 2007 for studies published in English. The terms rehabilitation and hip fracture were exploded in order to obtain related search terms and categories.

Study Selection

In the initial search of the databases, a combined total of 1031 articles was identified. Studies that did not focus on hip fracture rehabilitation, did not include persons over the age of 50 years, and/or did not include measures of physical outcome were excluded.

Data Extraction

Only studies with an Oxford Center for Evidence-Based Medicine Levels of Evidence level of I (randomized controlled trial, RCT) or II (cohort) were reviewed. The methodologic quality of both types of studies was assessed using a modified version of the Downs and Black checklist.

Data Synthesis

There were 55 studies that met our selection criteria: 30 RCTs and 25 nonrandomized trials. They were distributed across 6 categories for rehabilitation intervention (care pathways, early rehabilitation, interdisciplinary care, occupational and physical therapy, exercise, intervention not specified) and 3 settings (acute care hospital, postacute care/rehabilitation, postrehabilitation).

Conclusions

When looking across all of the intervention types, the most frequently reported positive outcomes were associated with measures of ambulatory ability. Eleven intervention categories across 3 settings were associated with improved ambulatory outcomes. Seven intervention approaches were related to improved functional recovery, while 6 intervention approaches were related to improved strength and balance recovery. Decreased length of stay and increased falls self-efficacy were associated with 2 interventions, while 1 intervention had a positive effect on lower-extremity power generation.     

Baseline Predictors of Fatigue 1 Year After Mild Head Injury

de Leon MB, Kirsch NL, Maio RF, Tan-Schriner CU, Millis SR, Frederiksen S, Tanner CL, Breer ML. Baseline predictors of fatigue 1 year after mild head injury.

Objective

To compare reports of fatigue 12 months after minor trauma by participants with mild head injury (MHI) with those with other injury, and identify injury and baseline predictors of fatigue.

Design

An inception cohort study of participants with MHI and other nonhead injuries recruited from and interviewed at the emergency department (ED), with a follow-up telephone interview at 12 months.

Setting

Level II community hospital ED.

Participants

Participants (n=58) with MHI and loss of consciousness (LOC) of 30 minutes or less and/or posttraumatic amnesia (PTA) less than 24 hours, 173 with MHI but no PTA/LOC, and 128 with other mild nonhead injuries. Inclusion criteria: age 18 years or older, within 24 hours of injury, Glasgow Coma Scale score of 13 or higher, and discharge from the ED.

Interventions

Not applicable.

Main Outcome Measure

Medical Outcomes Study 36-Item Short-Form Health Survey Vitality subscale.

Results

Significant predictors of fatigue severity at 12 months were baseline fatigue, having seen a counselor for a mental health issue, medical disability, marital status, and in some stage of litigation. Injury type was not a significant predictor.

Conclusions

Fatigue severity 12 months after injury is associated with baseline characteristics and not MHI. Clinicians should be cautious about attributing persisting fatigue to MHI without comprehensive consideration of other possible etiologic factors.     

Segmental spinal reflex adaptations associated with chronic ankle instability

Sefton JM, Hicks-Little CA, Hubbard TJ, Clemens MG, Yengo CM, Koceja DM, Cordova ML. Segmental spinal reflex adaptations associated with chronic ankle instability.

Objective

To further understanding of the role that segmental spinal reflexes play in chronic ankle instability (CAI).

Design

A 2 × 2 repeated-measures case-control factorial design. The independent variables were ankle group with 2 levels (healthy, CAI) and stance with 2 levels (single, double legged).

Setting

University research laboratory.

Participants

Twenty-two participants with CAI and 21 matched healthy controls volunteered.

Interventions

Not applicable.

Main Outcome Measures

The dependent variables were 2 measures of motoneuron pool excitability: paired reflex depression (PRD) and recurrent inhibition.

Results

A 2 × 2 repeated-measures multivariate analysis of variance revealed a significant interaction between group and stance on the linear combination of PRD and recurrent inhibition variables (Wilks λ=.808, F_2,40=4.77, P=.014). Follow-up univariate F tests revealed an interaction between group and stance on the PRD (F_1,41=9.74, P=.003). Follow-up dependent t tests revealed a significant difference between single- and double-legged PRD in the healthy participants (t₂₀=-3.76, P=.001) with no difference in CAI participants (t₂₁=-0.44, P=.67). Finally, there was a significant difference in recurrent inhibition between healthy (mean, 83.66) and CAI (mean, 90.27) (P=.004).

Conclusions

This study revealed that, compared with healthy participants, CAI participants were less able to modulate PRD when going from a double- to a single-legged stance. Additionally, CAI participants showed higher overall levels of recurrent inhibition when compared with healthy matched controls.     

Reproducibility of the ABILOCO Questionnaire and Comparison Between Self-Reported and Observed Locomotion Ability in Adult Patients With Stroke

Caty GD, Theunissen E, Lejeune TM. Reproducibility of the ABILOCO questionnaire and comparison between self-reported and observed locomotion ability in adult patients with stroke.

Objectives

To test the reproducibility of the ABILOCO questionnaire. To validate the patient self-reporting method and the third-party assessment of the stroke patients' locomotion ability by a treating physical therapist.

Design

Prospective study.

Setting

University hospital.

Participants

Adult stroke patients (N=28; 59±13y). The time since stroke ranged from 3 to 253 weeks.

Interventions

Not applicable.

Main Outcome Measure

The ABILOCO questionnaire.

Results

The results of patient self-assessment and the results of the third-party assessments by the physiotherapists at a 2-week interval were highly correlated (intraclass correlation coefficient [ICC]=.77 and ICC=.89, respectively). The results of the patient self-assessment and the third-party assessment by the physical therapist were both well correlated to assessment by an independent medical examiner who observed the patient during the 13 ABILOCO activities (ICC=.69 and ICC=.87, respectively).

Conclusions

The use of ABILOCO as a self-reporting questionnaire is a valid and reproducible method for assessing locomotion ability in patients with stroke in daily clinical practice and research.     

Higher Muscle Passive Stiffness in Parkinson's Disease Patients Than in Controls Measured by Myotonometry

Marusiak J, Kisiel-Sajewicz K, Jaskólska A, Jaskólski A. Higher muscle passive stiffness in Parkinson's disease patients than in controls measured by myotonometry.

Objective

To assess muscle passive stiffness in medicated Parkinson's disease patients using myotonometry.

Design

Case-control study.

Setting

Kinesiology laboratory.

Participants

Women with Parkinson's disease (PD) (n=8) and healthy matched elderly women (controls) (n=10) (mean age: PD, 77±3y; controls, 77±4y).

Interventions

Not applicable.

Main Outcome Measures

Passive stiffness of relaxed biceps brachii (BB) muscle was measured using myotonometry. Additionally, surface electromyographic and mechanomyographic signals were recorded from the muscle at rest, and amplitude of those signals was analyzed offline.

Results

The values of BB muscle passive stiffness were significantly (P=.004) higher in PD than in the controls, with a statistically significant influence of parkinsonian rigidity score (Unified Parkinson's Disease Rating Scale) on intergroup differences (P<.001). The Spearman correlation coefficient ρ value showed a significant (P=.005) positive relationship (ρ=.866) between the parkinsonian rigidity score and passive stiffness values of BB in PD. The groups did not differ significantly in the electromyogram amplitude (P=.631) and mechanomyogram amplitude (P=.593) of the BB muscle, and values of these parameters did not correlate significantly with rigidity score (P=.555, P=.745, respectively) in the patients.

Conclusions

Myotonometer is a sensitive enough tool to show that PD patients have higher muscle passive stiffness than healthy controls.     

Ambulatory oxygen therapy assessment: a comparative study of incremental shuttle and 6-minute walking tests

Background

Walking tests, such as the incremental shuttle walk test (ISWT) and the 6-minute walk test (6MWT), are recommended in the assessment of ambulatory oxygen for patients with chronic obstructive pulmonary disease (COPD). However, there is no evidence that these tests can be used interchangeably.

Objectives

To compare the ISWT and the 6MWT in COPD patients in terms of indication for ambulatory oxygen therapy.

Design

Crossover design.

Setting

Patients attended as outpatients.

Participants

Fifty patients with stable COPD (31 males; age 67 years, range 43 to 83 years); mean forced expiratory volume in 1 second 1.2 l [standard deviation (SD) 0.6 l] and 48.6% predicted (SD 23.4%).

Intervention

Patients performed both the ISWT and the 6MWT whilst breathing air. Breathlessness (Borg scale), percutaneous arterial oxygen saturation (SpO₂) and heart rate were measured before and after both tests.

Main outcome measures

Post-test SpO₂ and change from baseline.

Results

The mean change in saturation was −4.6% (SD 6.2%) and −2.8% (SD 5.3%) after the ISWT and the 6WMT, respectively. Using Bland and Altman plots, the limits of agreement for difference in change in SpO₂ (%) between the two tests were wide (−8.1 to 11.6) and clinically relevant. Sixteen patients (32%) and 13 patients (26%) met the criteria for ambulatory oxygen with the ISWT and the 6MWT, respectively (P = 0.32).

Conclusions

This study found a wide variation between differences in exercise oxygen desaturation after the ISWT compared with the 6MWT, supporting the premise that these tests should not be used interchangeably in the assessment of ambulatory oxygen for COPD patients.