This paper has reviewed the acute and long-term responses to changes in vertical posture in normal and tetraplegic subjects. It has discussed physiological mechanisms causing orthostatic hypotension in acute cervical spinal cord injured patients, and subsequent factors contributing to its amelioration over time. The long-term adaptive mechanisms are still controversial, probably involving multiple neurological, endocrine, renal, cardiovascular and haemodynamic factors. These factors include inhibition of vagal tone, plasma catecholamine levels, sensitivity of vascular beds to catecholamines, stretch reflexes in blood vessels, spinal BP reflexes, renin-angiotensin system, aldosterone and plasma volume changes. Individual differences may also interact with these various mechanisms, further complicating the issues. Although the fact that most tetraplegics do improve their orthostatic tolerance over time with repeated tilting is manifest, the precise mechanisms allowing this improvement are not. Research is needed to clarify these adaptive mechanisms, as well as to investigate the physiological effects of long-term therapeutic standing in devices such as standing frames.
Systems of functional electrical stimulation (FES) have been demonstrated to enable some persons with paraplegia to stand and ambulate limited distances. However, the energy costs and acute physiologic responses associated with FES standing activities have not been well investigated.
To compare the physiologic responses of persons with paraplegia to active FES-assisted standing (AS) and frame-supported passive standing (PS).
Fifteen persons with paraplegia (T6-T11) previously habituated to FES ambulation, completed physiologic testing of PS and AS. The AS assessments were performed using a commercial FES system (Parastep-1; Altimed, Fresno, Calif); the PS tests used a commercial standing frame (Easy Stand 5000; Altimed, Fresno, Calif). Participants also performed a peak arm-cranking exercise (ACE) test using a progressive graded protocol in 3-minute stages and 10-watt power output increments to exhaustion. During all assessments, metabolic activity and heart rate (HR) were measured via open-circuit spirometry and 12-lead electrocardiography, respectively. Absolute physiologic responses to PS and AS were averaged over 1-minute periods at 5-minute intervals (5, 10, 15, 20, 25, and 30 minutes) and adjusted relative to peak values displayed during ACE to determine percentage of peak (%pk) values. Absolute and relative responses were compared between test conditions (AS and PS) and across time using two-way analysis of variance.
The AS produced significantly greater values of VO2 (43%pk) than did PS (20%pk). The mean HR responses to PS (100-102 beats per minute [bpm] throughout) were significantly lower than during AS, which ranged from 108 bpm at 5 minutes to 132 bpm at test termination.
Standing with FES requires significantly more energy than does AS and may provide a cardiorespiratory stress sufficient to meet minimal requirements for exercise conditioning.
The routine clinical use of supported standing in hospitals, schools and homes currently exists. Questions arise as to the nature of the evidence used to justify this practice. This systematic review investigated the available evidence underlying supported standing use based on the Center for Evidence-Based Medicine (CEBM) Levels of Evidence framework.
The database search included MEDLINE, CINAHL, GoogleScholar, HighWire Press, PEDro, Cochrane Library databases, and APTAs Hooked on Evidence from January 1980 to October 2009 for studies that included supported standing devices for individuals of all ages, with a neuromuscular diagnosis. We identified 112 unique studies from which 39 met the inclusion criteria, 29 with adult and 10 with pediatric participants. In each group of studies were user and therapist survey responses in addition to results of clinical interventions.
The results are organized and reported by The International Classification of Function (ICF) framework in the following categories: b4: Functions of the cardiovascular, haematological, immunological, and respiratory systems; b5: Functions of the digestive, metabolic, and endocrine systems; b7: Neuromusculoskeletal and movement related functions; Combination of d4: Mobility, d8: Major life areas and Other activity and participation. The peer review journal studies mainly explored using supported standers for improving bone mineral density (BMD), cardiopulmonary function, muscle strength/function, and range of motion (ROM). The data were moderately strong for the use of supported standing for BMD increase, showed some support for decreasing hypertonicity (including spasticity) and improving ROM, and were inconclusive for other benefits of using supported standers for children and adults with neuromuscular disorders. The addition of whole body vibration (WBV) to supported standing activities appeared a promising trend but empirical data were inconclusive. The survey data from physical therapists (PTs) and participant users attributed numerous improved outcomes to supported standing: ROM, bowel/bladder, psychological, hypertonicity and pressure relief/bedsores. BMD was not a reported benefit according to the user group.
There exists a need for empirical mechanistic evidence to guide clinical supported standing programs across practice settings and with various-aged participants, particularly when considering a life-span approach to practice.
The initial level of injury and severity of volitional motor and clinically detectable sensory impairment has been considered the most reliable for predicting neurologic recovery of function afterspinal cord injury (SCI). This consensus implies a limited expectation for physicalrehabilitation interventions as important in the facilitation of recovery of function. The development of pharmacologic and surgical interventions has always been pursued with the intent of altering the expected trajectory of recoveryafter SCI, but only recently physicalrehabilitation strategies have been considered to improve recovery beyond the initial prognosis. This article reviews the recent literature reporting emerging activity-based therapies that target recovery of standing and walking based on activity-dependent neuroplasticity. A classification scheme for physicalrehabilitation interventions is also discussed to aid clinical decision making.
STUDY DESIGN: Prospective study on patients with spinal cord injuries. OBJECTIVES: To evaluate the loss of bone mineral density (BMD) in various body regions of patients with spinal cord injury (SCI) and its dependence on weight bearing activities during 2 years post injury. METHODS: BMD of the whole body was measured in patients with SCI. Baseline measurement was performed in 6-16 weeks after SCI, the second and the third-respectively 12 and 24 months after injury. Fifty-four subjects were selected and divided into two groups: standing and non-standing. From these groups 27 pairs were made according to gender, age and height. RESULTS: There was found to be a well-marked decrease in BMD values for lower extremities, but there was no significant difference between paraplegic and tetraplegic patients 1 and 2 year after injury. Leg BMD reduced by 19.62% (95% CI, 17-22%) in the standing group and by 24% (95% CI, 21-27%) in non-standing group during the first year. Two years after SCI patients in standing group had significantly higher leg BMD-1.018 g/cm(2) (95% CI, 0.971-1.055 g/cm(2)) than in the non-standing group-0.91 g/cm(2) (95% CI, 0.872-0.958 g/cm(2)) (P<or=0.0001). CONCLUSION: SCI patients who performed daily standing >or=1 h and not less than 5 days per week, had significantly higher BMD in the lower extremities after 2 years in comparison to those patients who did not perform standing.
author: Harvey LA, Byak AJ, Ostrovskaya M, Glinsky J, Katte L, Herbert RD.
publication: Aust J Physiother. 2003;49(3):176-81.
The aim of this assessor-blind randomised controlled trial was to determine the effect of four weeks of 30 minute stretches each weekday on extensibility of the hamstring muscles in people with recent spinal cord injuries. A consecutive sample of 16 spinal cord-injured patients with no or minimal voluntary motor power in the lower limbs and insufficient hamstring muscle extensibility to enable optimal long sitting were recruited. Subjects’ legs were randomly allocated to experimental and control conditions. The hamstring muscles of the experimental leg of each subject were stretched with a 30 Nm torque at the hip for 30 minutes each weekday for four weeks. The hamstring muscles of the contralateral leg were not stretched during this period. Extensibility of the hamstring muscles (hip flexion range of motion with knee extended, measured with a 48 Nm torque at the hip) of both legs was measured by a blinded assessor at the commencement of the study and one day after the completion of the four-week stretch period. Changes in hamstring muscle extensibility from initial to final measurements were calculated. The effect of stretching was expressed as the mean difference in these changes between stretched and non-stretched legs. The mean effect of stretching was 1 degree (95% CI -2 to 5 degrees). Four weeks of 30 minute stretches each weekday does not affect the extensibility of the hamstring muscle in people with spinal cord injuries.
The concept of a wheelchair cushion fitting clinic for the prevention of pressure sores is reviewed in the light of recent estimates of the cost of pressure sores in the U.K. A method for measuring the pressure beneath the ischial tuberosities is discussed and techniques for measuring a patient’s habitual exercise frequency and seated posture are described. Results from the records of 600 spinal injury patients including Rancho Los Amigos Hospital are reported and used to demonstrate the importance of low pressure beneath the ischial tuberosities as an indicator of wheelchair cushion suitability.
Pressure ulcers are a major complication of spinal cord injury (SCI) and have a significant effect on general health and quality of life. The objectives of this retrospective chart review were to determine prevalence, duration, and severity of pressure ulcers in veterans with SCI and to identify predictors of (1) outcome in terms of healing without surgery, not healing, or referral for surgery; (2) number of visits veterans made to the SCI outpatient clinic or received from home care services for pressure ulcer treatment; and (3) number of hospital admissions and days hospitalized for pressure ulcer treatment. From a sampling frame of 553 veterans on the Houston Veterans Affairs Medical Center SCI roster, 215 (39%) were reported to have visited the clinic or received home care for pressure ulcers (ICD-9 code 707.0 = decubitus, any site) during the 3 years studied (1997, 1998, and 1999). From this sample, 102 veterans met the inclusion criteria for further analyses, 56% of whom had paraplegia. The duration of ulcers varied greatly from 1 week to the entire 3-year time-frame. Overall, Stage IV pressure ulcers were the most prevalent as the worst ulcer documented. Number and severity of ulcers predicted outcome and healthcare utilization. This study illustrates the magnitude of the pressure ulcer problem among veterans with SCI living in the community. Reducing the prevalence of pressure ulcers among veterans with SCI will have a significant impact on the Department of Veterans Affairs’ financial and social resources. Innovative approaches are needed to reduce pressure ulcer risk in veterans with SCI.
author: Cybulski GR, Penn RD, Jaeger RJ.
publication: Neurosurgery. 1984 Jul;15(1):132-46.
Functional neuromuscular stimulation (FNS) provides a mechanism for the activation of muscles paralyzed by injury to the spinal cord. Although this technique was first used to treat patients with spinal cord injury over 20 years ago, only recent advances in electronics and biomechanics have made it a promising aid for the rehabilitation of these patients. Thus far, restoration of palmar prehension and lateral prehension in quadriplegics and of standing and biped gait in paraplegics has been achieved under carefully controlled laboratory conditions. This article reviews the current status of FNS and its potential as a practical tool to aid spinal cord-injured patients. Neurosurgeons who care for these patients might be expected to be involved in the future use of FNS if implantable systems are developed and tested.