The average person stands upon waking in the morning, stands to complete hygiene activities, stands to shower and possibly to prepare breakfast. Children walk to and from the school bus, walk between classes, and most likely stand during gym class and recess. They may also participate in after-school sports or recreational activities that involve standing. But for children with physical disabilities, there is a strong likelihood they may remain sitting for all of these activities.
Most typically developing infants begin pulling to stand by 10 months of age and never look back. Standing during early development provides loading forces to assist with skeletal modeling, bone growth and strength; if the forces are absent or atypical, abnormal bone development may occur.1,2
In particular, hip joint and acetabular modeling are directly influenced by weight-bearing forces. Without these forces, the acetabulum may remain shallow, which can be a factor contributing to future hip subluxation or dislocation and possible need for surgical intervention. Terjesen found an increased risk of hip displacement in patients with quadriplegic cerebral palsy under the age of 5 years who cannot walk.3 Appropriate loading forces, as well as muscle activation, in typical development also help to resolve bony rotation and varum/valgum positioning of the lower extremities of a young child.4
Lack of weight-bearing forces can also contribute to the development of osteopenia or osteoporosis, significantly increasing the risk of fractures. Children with disabilities, already at risk for osteopenia from immobility and lack of regular weight-bearing, often have additional risk factors, including inadequate nutrition from poor oral-motor skills, vomiting secondary to gastro-esophageal reflux disease, and use of seizure medications or steroids.1
While some of these factors may not be changeable, the development of a regular standing program to improve weight-bearing is directly within the scope of physical therapist practice.
In addition to skeletal modeling and prevention of osteopenia and fractures, therapists, patients and parents often report other benefits from standing. A study by Taylor found that therapists' most commonly reported benefits of standing were pressure relief, bone strengthening, improving joint range of motion/soft-tissue flexibility, and enhancement of social and educational opportunities.5
Other benefits included reducing spasticity, preventing hip dislocations, and promoting muscle strength, bowel, bladder and cardiovascular function.5 Personally, I have also heard therapists and parents report improvement in level of alertness and secretion clearance.
In a study by Eng et al, patients with spinal cord injuries reported perceived benefits of participating in a standing program. These included a feeling of well-being, improvements in circulation, reflex activity, bowel and bladder function, self-care, digestion, breathing, skin integrity, fatigue and sleep, as well as decreased pain and muscle spasm.6
For children (and adults) who are not capable of standing on their own, there are several available standing frames to enable upright positioning and weight-bearing through the lower extremities.
These devices have become more user-friendly and are generally easy to adjust if shared between multiple users, such as in a school or hospital setting. While they are meant to be used on a daily basis by families and school personnel, a physical therapist should evaluate a patient's appropriateness and tolerance for standing and prescribe a particular standing device, needed supports and parameters for standing.
To determine whether a patient is a candidate for supported standing, a full evaluation should be completed, including vital signs (e.g., heart rate, oxygen saturation and blood pressure) before, during and after a standing trial.
It should be noted that a patient not accustomed to standing may experience orthostatic hypotension upon standing, and that heart rate generally increases upon standing.7
Evaluation should also include respiratory status, circulation, postural control, range of motion and the patient's ability to assist with transfers. The primary caregiver and environment should also be considered. Will the caregiver be able to complete the needed transfer? Will there be help available if needed? Are there time and space considerations?
The physical therapist should determine whether the patient has the full range of motion required for typical standing or, if not, whether full range can be achieved by splinting or bracing.
For patients with a history of fractures, recent surgery or dependent edema, the therapist may want to consult with the patient's physician prior to starting a standing program. The therapist should be clear on the goal for standing. Along with patient evaluation, the ultimate goal-whether to decrease pressure from sitting or improve bone-mineral density, range of motion, psychological well being, or bowel and bladder function-will be a factor in determining the type of stander prescribed.
Types of Standers
Prone standers provide anterior support, allowing the patient to be tilted forward while standing. This can help facilitate weight-bearing through the upper extremities. The patient should have fairly good head control to maintain anti-gravity positioning. This position may be used to facilitate or encourage active head control and proximal strengthening.
In many cases, patients need to be physically lifted into prone standers; mechanical lifts are generally not appropriate. While prone standers provide standing ability for patients unable to maintain a fully upright position, it should be noted that with the stander tilted forward there will be significantly less weight-bearing through the long bones of the lower extremities and the calcanei.
Supine standers and tilt tables provide full support posteriorly. This is helpful for patients with poor head and trunk control. The standing angle is easily adjusted and can be increased within a standing session as tolerated. Supine standers generally allow for ease of transfers, including stand-pivot transfers or use of a mechanical lift. At a fully upright angle, weight-bearing forces will be directed more typically through the lower extremities.7 These forces change as the angle is reclined.
If the patient does not have the range of motion at the hips, knees and ankles required for typical standing, the weight-bearing forces will also be altered, even at a fully upright angle. If the goal is to improve bone-mineral density, the best strategy is to use bracing as appropriate to achieve neutral range of motion and an upright standing angle.7
This might not be essential if there is a different goal, but therapists should also consider that the patient's angle of vision will be affected by tilt in a supine stander. This can impact the person's ability to interact with peers and the environment as well as participate in functional skills. While supine standers can be used with various populations, they are generally large devices that require a great deal of space.
Upright standers provide the most typical anatomical alignment if the patient can achieve and maintain lower-extremity standing range of motion. However, a patient must have relatively good head and trunk control.
Transfers to the device are generally by sit-to-stand or dependent lift. These standers are typically lower to the ground, allowing for better peer interaction. A disadvantage of these standers is that most models are not made for taller individuals. The base must become exponentially larger for a taller-height device to prevent tipping, which would increase the space needed for this device.
Ease of Transfer
Sit-to-stand frames and wheelchairs are becoming more popular. These devices allow for ease of transfer. Patients can be transferred in the same manner as they would to their wheelchairs-sliding transfers, stand-pivot or dependent or mechanical lifts can all be used. These devices can easily transition sit to/from stand and angles between. They can be self-operated if the patient has upper-extremity control.
Standers generally transition with a lever, while wheelchairs are often powered by button or joystick. These devices work well for patients with decreased range of motion, especially at the hips or knees, and can provide a prolonged stretch.
However, if the device does not go fully upright or if range of motion is limited, weight-bearing forces will be altered (most likely increased through the anterior knee and decreased through the tibia and calcaneus).7 If the goal is to improve range of motion, this can be acceptable, but may not be effective if the goal is to improve bone-mineral density.
Mobile or dynamic standers allow self-propulsion while the patient is standing. This option is most typically seen in upright or sit-to-stand models. It allows the increased benefit of mobility while standing, enabling the patient to better participate in functional tasks rather than standing in a static location. This can enable a child to explore the environment and interact with peers more effectively while standing.
Newer models considered to be dynamic standers permit weight-shifting and trunk movement while standing (allowing dynamic movement of the individual rather than movement of the entire device).
Therapists often hear that there is little evidence to support the use of standing devices. The reality is, there is little published research on the topic, not that the published literature does not indicate there are benefits to standing.
At the 2010 APTA Combined Sections Meeting, Ginny Paleg, PT, MPT, DScPT, presented "Supported Standing: Integrating Evidence into Practice," in which she discussed her extensive literature search regarding the effectiveness of standing.7
Dr. Paleg showed there is evidence to support standing, but some of the higher-level research has been done with patients with spinal cord injuries or those in nursing homes. This research may be overlooked when literature searches are limited to pediatric populations.
According to Dr. Paleg, published research has shown the following: The highest evidence exists to support standing for the improvement of bone-mineral density with patients standing at least one hour per day with their lower extremities fully weight-bearing.
There is moderate-level evidence to support standing to decrease spasticity and improve range of motion (patients standing 30-45 minutes at a time). More studies are needed to show skin integrity, bowel/bladder function and sleep/fatigue benefits.
Pin also published a systematic review of the literature to examine evidence of the effectiveness of static weight-bearing.8 These results concluded that there is evidence for increased bone density and temporary reduction of spasticity, but evidence for additional benefits remains limited by an inadequate number of studies, small number of subjects and inadequate rigor of the research designs.
More Research Needed
In conclusion, physical therapists routinely prescribe static standing programs for patients with limited mobility for a variety of benefits. Published literature has shown the effectiveness of standing to improve bone-mineral density, temporarily decrease spasticity and improve range of motion.
Anecdotally, therapists, patients and family members also credit standing for improvements in bowel/bladder function and regularity, respiratory status, skin integrity, sleep/fatigue/alertness levels and psychological well-being. More research is needed to objectively show the effectiveness of standing in these areas.
Further high-level research is also needed to show the effectiveness of standing in general, with more detail provided in the methodology used (e.g., type of stander, angle of tilt, amount of weight-bearing, range-of-motion limitations, duration and frequency of standing).
Therapists need to complete a full assessment of the patient to determine the most appropriate device and standing parameters. Therapists should be clear on the goal of standing for each individual to achieve the best results.
1. Ward, K., Caulton, J., Adams, J., & Mughal, M. (2006). Perspective: Cerebral palsy as a model of bone development in the absence of postnatal mechanical factors. Journal of Musculoskeletal & Neuronal Interactions, 6(2), 154-159.
2. Orlin, M., & Lowes, L. (2005). Musculoskeletal system: Considerations and interventions for specific pediatric pathologies. In: Effgen, S.K., Meeting the Physical Therapy Needs of Children. Philadelphia, PA: F.A. Davis Co., 155-184.
3. Terjesen, T. (2006). Development of the hip joints in unoperated children with cerebral palsy. Acta Orthopaedica, 77(1), 125-131.
4. Orlin, M., & Lowes, L. (2005). Musculoskeletal system: Structure, function, and evaluation. In: Effgen, S.K., Meeting the Physical Therapy Needs of Children. Philadelphia, PA: F.A. Davis Co., 131-154.
5. Taylor, K. (2009). Factors affecting prescription and implementation of standing-frame programs by school-based physical therapists for children with impaired mobility. Pediatric Physical Therapy, 21, 282-288.
6. Eng, J., Levins, S., Townson, A., et al. (2001). Use of prolonged standing for individuals with spinal cord injuries. Physical Therapy, 81(8), 1392-1399.
7. Paleg, G., & Glickman, L. (2010). Supported Standing: Integrating Evidence into Practice. PowerPoint presentation 2009 (presented at APTA Combined Sections Meeting, San Diego, CA, February 2010).
8. Pin, T. (2007). Effectiveness of static weight-bearing exercises in children with cerebral palsy. Pediatric Physical Therapy, 19, 62-73.
Laura Dobrich is a physical therapist at the Western Pennsylvania School for Blind Children in Pittsburgh, PA, as well as Children's Hospital of Pittsburgh.