Bone adaptation to altered loading after spinal cord injury: a study of bone and muscle strength

Bone loss from the paralysed limbs after spinal cord injury (SCI) is well documented. Under physiological conditions, bones are adapted to forces which mainly emerge from muscle pull. After spinal cord injury (SCI), muscles can no longer contract voluntarily and are merely activated during spasms. Based on the Ashworth scale, previous research has suggested that these spasms may mitigate bone losses. We therefore wished to assess muscle forces after SCI with a more direct measure and compare it to measures of bone strength. We hypothesized that the bones in SCI patients would be in relation to the loss of muscle forces. Six male patients with SCI 6.4 (SD 4.3) years earlier and 6 age-matched, able-bodied control subjects were investigated. Bone scans from the right knee were obtained by pQCT. The knee extensor muscles were electrically stimulated via the femoral nerve, isometric knee extension torque was measured and patellar tendon force was estimated. Tendon force upon electrical stimulation in the SCI group was 75% lower than in the control subjects (p<0.01). Volumetric bone mineral density of the patella and of the proximal tibia epiphysis were 50% lower in the SCI group than in the control subjects (p<0.01). Cortical area was lower by 43% in the SCI patients at the proximal tibia metaphysis, and by 33% at the distal femur metaphysis. No group differences were found in volumetric cortical density. Close curvilinear relationships were found between stress and volumetric density for the tibia epiphysis (r(2)=0.90) and for the patella (r(2)=0.91). A weaker correlation with the tendon force was found for the cortical area of the proximal tibia metaphysis (r(2)=0.63), and none for the distal femur metaphysis. These data suggest that, under steady state conditions after SCI, epiphyseal bones are well adapted to the muscular forces. For the metaphysis of the long bones, such an adaptation appears to be less evident. The reason for this remains unclear

Exercise therapy and cognitive behavioural therapy to improve fatigue, daily activity performance and quality of life in Postpoliomyelitis Syndrome: the protocol of the FACTS-2-PPS trial

Contains fulltext : 88661.pdf (publisher's version ) (Open Access)BACKGROUND: Postpoliomyelitis Syndrome (PPS) is a complex of late onset neuromuscular symptoms with new or increased muscle weakness and muscle fatigability as key symptoms. Main clinical complaints are severe fatigue, deterioration in functional abilities and health related quality of life. Rehabilitation management is the mainstay of treatment. Two different therapeutic interventions may be prescribed (1) exercise therapy or (2) cognitive behavioural therapy (CBT). However, the evidence on the effectiveness of both interventions is limited. The primary aim of the FACTS-2-PPS trial is to study the efficacy of exercise therapy and CBT for reducing fatigue and improving activities and quality of life in patients with PPS. Additionally, the working mechanisms, patients' and therapists' expectations of and experiences with both interventions and cost-effectiveness will be evaluated. METHODS/DESIGN: A multi-centre, single-blinded, randomized controlled trial will be conducted. A sample of 81 severely fatigued patients with PPS will be recruited from 3 different university hospitals and their affiliate rehabilitation centres. Patients will be randomized to one of three groups i.e. (1) exercise therapy + usual care, (2) CBT + usual care, (3) usual care. At baseline, immediately post-intervention and at 3- and 6-months follow-up, fatigue, activities, quality of life and secondary outcomes will be assessed. Costs will be based on a cost questionnaire, and statistical analyses on GEE (generalized estimated equations). Analysis will also consider mechanisms of change during therapy. A responsive evaluation will be conducted to monitor the implementation process and to investigate the perspectives of patients and therapists on both interventions. DISCUSSION: A major strength of the FACTS-2-PPS study is the use of a mixed methods design in which a responsive and economic evaluation runs parallel to the trial. The results of this study will generate new evidence for the rehabilitation treatment of persons with PPS. TRIAL REGISTRATION: Dutch Trial Register NTR1371

'What you suggest is not what I expected': How pre-consultation expectations affect shared decision-making in patients with low back pain

OBJECTIVE: Existing studies on shared decision-making (SDM) have hardly taken into consideration that patients could have independently developed expectations prior to their consultation with a healthcare provider, nor have studies explored how such expectations affect SDM. Therefore, we explore how pre-consultation expectations affect SDM in patients with low back pain. METHODS: We performed a qualitative study through telephone interviews with 10 patients and seven care professionals (physicians, nurse, physician assistants) and 63 in-person observations of patient-physician consultations in an outpatient clinic in the Netherlands. Transcripts were analyzed through an open coding process. RESULTS: A discrepancy existed between what patients expected and what care professionals could offer. Professionals perceived they had to undertake additional efforts to address patients' 'unrealistic' expectations while attempting SDM. Patients, in turn, were often dissatisfied with the outcomes of the SDM encounter, as they believed their own expectations were not reflected in the final decision. CONCLUSION: Unaddressed pre-consultation expectations form a barrier to constructive SDM encounters. PRACTICAL IMPLICATIONS: Patients' pre-consultation expectations need to be explored during the SDM encounter. To achieve decisions that are truly shared by care professionals and patients, patients' pre-consultation expectations should be better incorporated into SDM models and education

Determining the anaerobic threshold in postpolio syndrome: comparison with current guidelines for training intensity prescription

To determine whether the anaerobic threshold (AT) can be identified in individuals with postpolio syndrome (PPS) using submaximal incremental exercise testing, and to compare current guidelines for intensity prescription in PPS with the AT. Cohort study. Research laboratory. Individuals with PPS (N=82). Not applicable. Power output, gas exchange variables, heart rate, and rating of perceived exertion (RPE) were measured in an incremental submaximal cycle ergometry test. Two independent observers identified the AT. Comparison of current guidelines for training intensity prescription in PPS (40%-60% heart rate reserve [HRR] or RPE of 12) with the AT was based on correlations between recommended heart rate and the heart rate at the AT. In addition, we determined the proportion of individuals that would have been recommended to train at an intensity corresponding to their AT. The AT was identified in 63 (77%) of the participants. Pearson correlation coefficients between the recommended heart rate and the heart rate at the AT were lower in cases of 40% HRR (r=.56) and 60% HRR (r=.50) than in cases of prescription based on the RPE (r=.86). Based on the RPE, 55% of the individuals would have been recommended to train at an intensity corresponding to their AT. This proportion was higher compared with 40% HRR (41%) or 60% HRR (18%) as criterion. The AT can be identified in most individuals with PPS offering an individualized target for aerobic training. If the AT cannot be identified (eg, because gas analysis equipment is not available), intensity prescription can best be based on the RP

Effects of stimulation pattern on electrical stimulation-induced leg cycling performance

Electrical stimulation-induced leg cycling (ES-LC) is beneficial for individuals with spinal cord injury (SCI), but cycling performance is often limited because of rapid fatigue of the stimulated muscles. This study evaluated whether a stimulation pattern with a catchlike-inducing pulse train increased force production and hence cycling performance. Five men with SCI performed ES-LC using different stimulation patterns: (1) the standard pattern with ramp modulation, (2) a pattern with no ramp modulation, (3) a pattern with no ramp modulation but with an initial doublet, and (4) a pattern with a middle doublet. None of the experimental patterns resulted in significantly improved cycling performance compared with the standard pattern. However, during the first 3 min of cycling, the current amplitude was significantly higher with the standard stimulation, suggesting that stimulation with no ramp modulation produces more force at the same submaximal current amplitude. The results do not indicate that stimulation with catchlike-inducing trains with the current parameter settings improves ES-LC performance

Exercise intensity of robot-assisted walking versus overground walking in nonambulatory stroke patients

It has been suggested that aerobic training should be considered in stroke rehabilitation programs to counteract detrimental health effects and decrease cardiovascular risk caused by inactivity. Robot-assisted treadmill exercise (using a Lokomat device) has the potential to increase the duration of walking therapy relative to conventional overground therapy. We investigated whether exercise intensity during Lokomat therapy is adequate to elicit a training effect and how assistance during walking in the Lokomat affects this exercise intensity. Ten patients with stroke (age 54 +/- 9 yr) walked in both the Lokomat and in a hallway. Furthermore, 10 nondisabled subjects (age 43 +/- 14 yr) walked in the Lokomat at various settings and on a treadmill at various speeds. During walking, oxygen consumption and heart rate were monitored. Results showed that for patients with stroke, exercise intensity did not reach recommended levels (30% heart rate reserve) for aerobic training during Lokomat walking. Furthermore, exercise intensity during walking in the Lokomat (9.3 +/- 1.6 mL/min/kg)was lower than during overground walking (10.4 +/- 1.3 mL/min/kg). Also, different settings of the Lokomat only had small effects on exercise intensity in nondisabled subjects

Metabolic load during morning care and active bed exercises in critically ill patients: An explorative study

Background: To avoid overexertion in critically ill patients, information on the physical demand, i.e., metabolic load, of daily care and active exercises is warranted. Objective: The objective of this study was toassess the metabolic load during morning care activities and active bed exercises in mechanically ventilated critically ill patients. Methods: This study incorporated an explorative observational study executed in a university hospital intensive care unit. Oxygen consumption (VO2) was measured in mechanically ventilated (≥48 h) critically ill patients during rest, routine morning care, and active bed exercises. We aimed to describe and compare VO2 in terms of absolute VO2 (mL) defined as the VO2 attributable to the activity and relative VO2 in mL per kilogram bodyweight, per minute (mL/kg/min). Additional outcomes achieved during the activity were perceived exertion, respiratory variables, and the highest VO2 values. Changes in VO2 and activity duration were tested using paired tests. Results: Twenty-one patients were included with a mean (standard deviation) age of 59 y (12). Median (interquartile range [IQR]) durations of morning care and active bed exercises were 26 min (21–29) and 7 min (5–12), respectively. Absolute VO2 of morning care was significantly higher than that of active bed exercises (p = 0,009). Median (IQR) relative VO2 was 2.9 (2.6–3.8) mL/kg/min during rest; 3.1 (2.8–3.7) mL/kg/min during morning care; and 3.2 (2.7–4) mL/kg/min during active bed exercises. The highest VO2 value was 4.9 (4.2–5.7) mL/kg/min during morning care and 3.7 (3.2–5.3) mL/kg/min during active bed exercises. Median (IQR) perceived exertion on the 6–20 Borg scale was 12 (10.3–14.5) during morning care (n = 8) and 13.5 (11–15) during active bed exercises (n = 6). Conclusion: Absolute VO2 in mechanically ventilated patients may be higher during morning care than during active bed exercises due to the longer duration of the activity. Intensive care unit clinicians should be aware that daily-care activities may cause intervals of high metabolic load and high ratings of perceived exertion