Wheelchair Assessment Special Considerations

Original Editor - Stacy Schiurring

Top Contributors - Stacy Schiurring  

Introduction

While the core wheelchair assessment process applies to all wheelchair users, certain conditions and postural presentations require additional clinical consideration. This Physiopedia page provides a concise clinical reference covering conditions and postural findings commonly encountered during wheelchair assessment, organised by category. For each, the focus is on how the condition or presentation affects the assessment process and informs wheelchair provision decisions.

Important Terminology

The WHO Wheelchair Service Training Package uses the terms fixed, flexible to neutral, and flexible part-way to neutralto describe postural outcomes during sitting balance assessment. Current rehabilitation and seating literature increasingly uses reducible and non-reducible as equivalent terms. A non-reducible posture broadly corresponds to a fixed posture, while a reducible posture encompasses both flexible to neutral and flexible part-way to neutral. Both sets of terms may be encountered in clinical practice and in research reviews, therefore they should be understood as complementary rather than contradictory.

In practical terms:

• A reducible posture or deformity can be moved toward neutral with gentle force. The goal of seating intervention is to support the user in the most neutral, functional position achievable
• A non-reducible posture or deformity cannot be corrected with gentle force. The goal of seating intervention is to accommodate the existing position, protect bony prominences, and prevent further deterioration

Strong force should never be applied during assessment to attempt correction of a posture. If it is unclear whether a presentation is reducible or non-reducible, refer to a more experienced clinician before proceeding.

Clinical Conditions for Wheelchair Assessment

This section will overview neurological and systemic conditions that affect how a wheelchair assessment is conducted and expectations on how the wheelchair user may present.

Spasticity

Spasticity is most commonly defined as a velocity-dependent increase in tonic stretch reflexes with exaggerated tendon jerks, resulting from hyperexcitability of the stretch reflex as a component of upper motor neuron syndrome. A broader clinical definition describes it as disordered sensorimotor control resulting from an upper motor neuron lesion, presenting as intermittent or sustained involuntary muscle activations.

Domain	Detail
Associated diagnoses	Spinal cord injury Cerebral palsy Acquired brain injury Stroke
Assessment triggers	Spasticity may be triggered or increased during assessment by hip, knee, or ankle position, or by touch and movement — particularly over uneven surfaces. Note which positions or movements trigger spasticity, whether it affects one or both sides, and the predominant pattern (eg. extensor pattern affecting the whole lower limb)
Assessment impact	High tone can create focal areas of high pressure between the user's body and the seating surface, increasing pressure injury risk. Ask the user how they manage their spasticity in daily life as their strategies may inform equipment decisions
Seating considerations	Involve the user in problem-solving around their spasticity. Increased pelvic support and a slight increase in seat dump (hips higher than knees) can reduce strong extensor patterns. Positioning footrests to increase knee flexion slightly beyond 90 degrees ('tucking' the feet) may also reduce extensor tone. Straps over the feet and knees may assist with lower limb control — ensure all straps use Velcro release for safety. For very strong or uncontrolled movements, a solid seat and backrest may be required. Select a wheelchair with an adjustable rear axle position and provide an anti-tip device where strong extension spasticity is present. Distribute pressure forces over a larger surface area and incorporate regular pressure relief into the user's routine

Altered Muscle Tone

Muscle tone is the resistance of muscles to passive stretch at rest. Normal tone is sufficient to resist gravity while allowing freedom of movement. Altered tone, whether elevated (hypertonia) or reduced (hypotonia), affects posture, movement, and seating requirements.

Domain	Detail
Associated diagnoses	Cerebral palsy Acquired brain injury Spinal cord injury Stroke
High tone (hypertonia)	Increased resistance to passive movement Movement may be slow, limited, or restricted to fixed patterns. When tone is very high, active movement may be minimal. Tone may increase with emotion or concentrated effort, meaning the user may present differently during assessment than in daily life
Low tone (hypotonia)	Reduced resistance to passive movement The user may have difficulty initiating or controlling movement Sometimes described as 'floppy' or 'flaccid' When very low, voluntary movement may be minimal
Assessment impact	Altered tone may contribute to reduced sitting balance, reduced propulsion ability and transfer safety, increased risk of fixed non-neutral postures, and risk of hip dislocation (both high and low tone are risk factors). Where tone is significantly elevated or reduced, there may be increased risk of aspiration difficulties — this should be escalated to the relevant clinician. When handling a user with altered tone, always explain what you are going to do before doing it, move slowly, and provide firm, comfortable support
Seating considerations (high tone)	If whole-limb extension occurs, flexing one joint (e.g., the knee) can sometimes reduce tone through the limb. Reduce the thigh-to-trunk angle to counter extensor patterns. Ensure postural support devices are strong enough to be effective against high tone forces. Distribute pressure over a larger surface area and monitor skin integrity frequently
Seating considerations (low tone)	The user is likely to require substantial postural support to maintain upright sitting. Position supports carefully to avoid pressure points

Hip Dislocation and Subluxation

Hip displacement has a higher prevalence in children who have never walked independently, as the acetabulum is shaped by femoral head movement during weight-bearing in early development. If the hip joint does not develop correctly, subluxation or dislocation can result.] Hip displacement is also associated with high tone, habitual windswept positioning, and low tone where muscles and ligaments are insufficient to stabilise the joint.

Note: Hip dislocation is not always painful. Absence of pain does not exclude the diagnosis.

Domain	Detail
Associated diagnoses	Cerebral palsy Children who have never walked independently High tone conditions Low tone conditions Traumatic brain injury
Assessment indicators	Apparent leg length discrepancy One leg consistently positioned closer to midline Pain with hip movement Restricted or asymmetrical hip range of motion Inability to achieve or maintain neutral hip posture; windswept lower limb positioning
Assessment impact	Move the hips gently during assessment and avoid causing pain. Do not attempt to correct hip position forcibly. If hip dislocation or subluxation is suspected and you are not experienced in assessing for it, refer to a medical officer or experienced physiotherapist before proceeding with prescription
Seating considerations	Avoid positions that cause pain. Support the pelvis and trunk in neutral or as close to neutral as possible, then support the hips and thighs as close to neutral as possible. Avoid overcorrecting leg posture, as this may cause the pelvis to move away from neutral. Discuss 24-hour positioning, including sleeping position, advise on positions that avoid windswept legs or sustained adduction
Prevention (paediatric)	Supporting neutral posture in sitting and lying from an early age, hip and thigh abduction support in young children, and standing in a standing frame have been shown to reduce the risk of hip displacement progression

Fatigue

Fatigue in wheelchair users may result from the additional energy cost of maintaining upright sitting, from the physical demands of propulsion, or from the nature of the user's underlying condition. It is particularly prevalent in people with progressive neurological conditions, post-polio syndrome, multiple sclerosis, and older adults.

Domain	Detail
Associated diagnoses	Multiple sclerosis Post-polio syndrome Progressive neuromuscular conditions Acquired brain injury Older adults Spinal cord injury
Assessment impact	Assessments typically take place at a scheduled appointment, when the user may be relatively rested. This can result in significant underestimation of postural support requirements. A user who sits well in the morning may demonstrate markedly reduced trunk control and increased pressure injury risk by the afternoon
Assessment strategies	Ask specifically about how posture and endurance change across the day. Where possible, conduct part of the assessment when the user is fatigued, or ask the user and caregiver to describe their posture and sitting ability at their most tired. This information is often more clinically useful than observations made during a morning appointment
Seating considerations	Factor the effects of fatigue on posture across a full day when determining how much postural support to provide. Consider incorporating resting positions into the wheelchair setup (eg. a tray with a cushion to allow forward arm-leaning, or tilt-in-space as an alternative resting position). Encourage rest periods out of the wheelchair during the day where possible

Epilepsy

Some wheelchair users have epilepsy, defined as a condition characterised by recurrent, unprovoked seizures resulting from disruption to normal brain electrical activity. Clinicians should understand both the seating implications of epilepsy and how to respond if a seizure occurs during assessment.

Domain	Detail
Associated diagnoses	Cerebral palsy Acquired brain injury Various neurological and metabolic conditions
Seizure types relevant to seating assessment	Partial seizures (with or without impaired consciousness) typically last under two minutes and involve uncontrolled movements or altered awareness. Generalised seizures involve complete loss of consciousness and may involve sudden falls. Understanding which type the user experiences informs both the assessment response and equipment decisions
If a seizure occurs during assessment	For a minor seizure: wait for it to end, then continue. For a major seizure: protect the user from injury by easing any fall, creating space around them, protecting the head with padding, loosening tight clothing, and timing the seizure duration. Do not attempt to remove the user from the wheelchair unless there is airway risk. Seek emergency medical assistance if the seizure lasts longer than five minutes or the user does not regain consciousness. Follow local emergency protocols and facility procedures
Seating considerations	Ensure all straps can be released quickly. If the user frequently experiences forward falls during seizures, pad any tray to reduce head injury risk. If epilepsy is not currently being treated, refer to a medical officer

Postural Presentations Considerations for Wheelchair Assessment

The postural presentations below are commonly identified during the physical assessment. Each can be reducible or non-reducible, and this distinction is the foundation of all seating intervention decisions.

Posterior Pelvic Tilt

Posterior pelvic tilt is one of the most common postural findings in wheelchair users. The pelvis is tipped backward, bringing the sacrum into greater contact with the seating surface and secondary causing thoracic kyphosis and forward head position. This posture significantly increases sacral and coccygeal pressure injury risk.

Domain	Detail
Assessment	In supine, assess hamstring length and hip flexion range. Determine whether the tilt is reducible (correctable with gentle support) or non-reducible. During hand simulation, assess whether pelvic support brings the pelvis toward neutral and observe the effect on trunk and head position
Reducible	Support the pelvis toward neutral using a posterior pelvic pad and pre-ischial shelf. Adjust seat dump to encourage anterior pelvic tilt. Ensure backrest shape supports the lumbar spine
Non-reducible	Accommodate the existing tilt. Open the seat-to-backrest angle to allow the hips to sit at less than 90 degrees. Ensure adequate posterior support and manage sacral/coccygeal pressure through cushion selection

Anterior Pelvic Tilt

Anterior pelvic tilt results in the pelvis tipping forward, with an associated increase in lumbar lordosis. It is less common than posterior tilt in wheelchair users but is associated with hip flexor tightness and strong extensor tone patterns.

Domain	Detail
Assessment	Assess hip flexor length and the presence of extensor spasticity. Determine reducibility during the pelvis posture screen and hand simulation
Reducible	A wedge cushion with the thicker aspect at the rear encourages posterior pelvic tilt and counters anterior tilt. An anterior pelvic strap may assist in maintaining the corrected position
Non-reducible	Accommodate the tilt Adjust seating angles and support accordingly Manage pressure over the ischial tuberosities

Pelvic Obliquity

Pelvic obliquity, where one side of the pelvis higher than the other, is a clinically significant finding due to its association with asymmetric pressure distribution, lateral spinal curvature, and pressure injury risk at the lower ischial tuberosity. Causes may be suprapelvic (secondary to scoliosis), intrapelvic (bony asymmetry), or infrapelvic (hip abduction or adduction contractures, leg length discrepancy).

Domain	Detail
Assessment	During the pelvis posture screen, identify which side is elevated and whether the obliquity is reducible. Assess hip abduction and adduction range on both sides. Identify whether the cause is above or below the pelvis, as this guides intervention
Reducible	Level the pelvis using a temporary foam build-up under the lower side during assessment. In the final seating system, a contoured cushion, ischial well, or segmented cushion may maintain pelvic leveling
Non-reducible	Accommodate the obliquity by building up under the lower side of the pelvis to fill the space and distribute pressure. Manage pressure carefully over the lower ischial tuberosity

Scoliosis

Scoliosis is a lateral curvature of the spine, typically with rotation, and is commonly encountered in non-ambulatory wheelchair users with neurological or neuromuscular conditions. Secondary scoliosis can develop from prolonged asymmetric seating posture, pelvic obliquity, or asymmetric tone.

Domain	Detail
Assessment	Observe spinal curvature in sitting, with and without support. Note curve direction, location (thoracic, lumbar, thoracolumbar), and any associated pelvic obliquity or rotation. Determine reducibility during hand simulation
Reducible	Three-point control is the principle for lateral trunk support in scoliosis, lateral support pads are applied at the apex of the curve and on the opposite side above and below to correct or accommodate the curve. Note that corrective support may restrict function; discuss this trade-off with the wheelchair user
Non-reducible	Accommodate the curve with contoured or custom seating. Manage pressure carefully, particularly at prominent bony areas. Refer to a specialist seating service for severe or complex deformity
Evidence note	Research indicates that custom-contoured seating shows greater mitigation of scoliosis progression in paediatric wheelchair users compared to modular seating systems

Kyphosis

Kyphosis is an excessive forward curvature of the thoracic spine. In wheelchair users, it is frequently associated with posterior pelvic tilt, low tone, or degenerative changes, and may affect respiratory function, swallowing, upper extremity reach, and visual field.

Domain	Detail
Assessment	Observe the level and degree of kyphosis. Determine whether correcting the pelvic tilt during hand simulation also reduces the kyphosis (suggesting a secondary relationship) or whether the kyphosis is independent. Assess respiratory function and head/neck position
Reducible	Addressing posterior pelvic tilt often reduces thoracic kyphosis. Ensure backrest shape and height support the thoracic spine without restricting shoulder blade movement in active propellers
Non-reducible	Accommodate the curve with backrest contouring. Consider the implications for respiratory function, head position, and visual field. Tilt-in-space may assist with head and neck balance over the trunk

Lower Limb Contractures

Contractures are fixed limitations in joint range. They are commonly encountered at the hip, knee, and ankle in long-term wheelchair users and in those with high tone conditions. They directly affect seat depth, footrest position, and the ability to achieve neutral pelvic positioning.

Domain	Detail
Assessment	Measure ROM at the hip (flexion, extension, abduction, adduction, rotation), knee (flexion and extension), and ankle (dorsiflexion and plantar flexion) bilaterally. Note asymmetries, as these affect measurement and prescription. Determine whether limitations are reducible or non-reducible
Hip flexion contracture	If hips cannot achieve 90 degrees of flexion, opening the seat-to-backrest angle (backrest recline) may be required to accommodate the contracture
Knee flexion contracture	May require footrest adjustment (angling or repositioning) and may affect seat depth — a shorter seat depth may be needed to avoid posterior calf pressure
Equinus (plantar flexion contracture)	Footplate position and footrest length require adjustment. If the foot cannot be plantigrade, measure to the toe rather than the heel and note footplate angle requirements
Asymmetric contractures	Where left and right sides differ, prescribe for the shorter or more restricted side to maintain pelvic level

Windswept Hips

Windswept hips describe a pattern where both hips are displaced to the same side: one hip in adduction and internal rotation, the other in abduction and external rotation. It is strongly associated with habitual asymmetric positioning, high tone, and hip dislocation risk. The hip in adduction and internal rotation carries the greatest risk of dislocation.

Domain	Detail
Associated presentations	Pelvic obliquity Scoliosis Hip dislocation or subluxation
Assessment	Observe lower limb positioning in both supine and sitting. Assess hip range of motion bilaterally. Identify the direction of displacement and the degree of reducibility
Seating considerations	Support the pelvis and hips as close to neutral as is comfortable. Use abduction supports where appropriate to reduce the adduction/internal rotation of the at-risk hip. Avoid overcorrection, which may cause pelvic displacement or pain
24-hour positioning	Discuss sleeping position with the user and caregiver: sustained asymmetric positioning during sleep significantly worsens windswept hips. Advise on positions that promote more symmetrical lower limb alignment