Power Assist Devices and the MAT Evaluation are two key elements in supporting mobility. This blog will explain the different types of power-assist systems and their functions. Also, learn how to recognise clinical indications for power-assist use in wheelchair users and the benefits and limitations of this technology in daily function. Additionally, gain a basic understanding of the MAT evaluation and its role in seating prescription. This blog will cover these elements of Power Assist Devices and the MAT Evaluation, and more.

Mechanical Assessment Tool (MAT) Seating Evaluation

What is a MAT Evaluation

A MAT assessment is a comprehensive physical and functional assessment conducted by an Occupational Therapist to determine the most appropriate wheelchair and seating system for an individual.

The MAT evaluation is a crucial step in the wheelchair prescription process, especially for individuals with complex physical needs.

Goal of the MAT evaluation

This evaluation involves assessing the person’s posture, range of motion, muscle tone, balance, and functional needs, both on and off the wheelchair.

The Pelvis and MAT Seating Evaluation

“The pelvis is the ‘foundation stone’ in sitting as it supports the person’s body weight above it. Pelvic positioning and stability affect the alignment of the head, trunk, upper and lower extremity” (Agency for Clinical Innovation, n.d.).

When there is asymmetrical alignment, this can result in increased pressure risks. When completing a MAT assessment, we first review the pelvis.

• When seated most body weight is located over the ischial tuberosities
• Ideal posture involves: A neutral tilt of the pelvis and a normal curve in the lumbar spine (lumbar lordosis)
• Understanding of where the body landmarks are and how to locate them is vital during the MAT evaluation.

MAT Evaluation Setup.

Tips:

• Have a measuring tape ready (for anthropometric measurements)
• Ask for consent for photos
• Observe the client’s breathing, comfort, and any pain cues
• Have all tools ready (goniometer, wedges, plinth, helper if needed) (Power Mobility, 2025).

Key Steps:

• Transfer the client using an appropriate method (e.g. hoist, pelican belt), also, consider how many therapists you would need
• Ensure the client is fully supported at first (therapist support as needed)
• Clothing should allow visibility of bony landmarks where possible.

MAT Seating Evaluation Process

Part 1: Seated current wheelchair evaluation

This involves assessing the client in their current wheelchair to identify the challenges and concerns experienced in that chair.

A hands on assessment is undertaken to review the client’s range of motion and pelvis to assess for any deformities such as pelvic rotation, pelvic obliquity and to determine whether the problem is fixed or flexible.

It is vital to observe the client from all angels (front, behind and side) and assess any habitual postures that are occurring (GTK, 2023).

Part 2: Supine Assessment

This assesses:

• Spinal alignment and pelvis in supine
• Assessing flexibility of deformity if a deformity is present
• Range of motion in hips, ankles and knees.
• Assess legs, (use of a goniometer would be beneficial here), you can passively move clients’ lower limbs to assess their movement and complete range of motion measurements
• Neurological functioning e.g. whether there is any presence of muscle wasting, spasticity, overall muscle functioning and sensations
• Skin and review of pressure risks (GTK, 2023).

Part 3: Unsupported Sitting Assessment

Set up for the assessment involves assisting the client into a sitting position on a firm surface (without the support of wheelchair/chair).

This is beneficial for simulation of supports for example lateral supports that could assist the client in their seating systems and assessment of pelvic positioning and posture (GTK, 2023).

MAT assessment – Considerations

• Pelvic alignment: is there a pelvic obliquity, rotation, or tilt?
• Spinal curvature: is there a normal curvature of the spine or is kyphosis, scoliosis, lordosis present—are they fixed or flexible?
• Hip range: abduction, adduction, rotation—can the hips be positioned neutrally?
• Trunk control: do they lose control of their trunk? Where does the client lose control—upper, mid, or lower trunk?
• Head and neck alignment: is there adequate support or is compensatory movement noted?
• Lower limb tone and contractures: especially in hamstrings, knees, and ankles.

Understanding overuse injuries in manual wheelchair users and preventing overuse

The frequent repetitive loading and movements which is required for the use of a manual wheelchair, in addition to other movements required to be completed by wheelchair users such as transfers places stress on manual wheelchair user’s upper limbs.

“71% of manual wheelchair users reported to have experienced shoulder pain at some point in their life”, (Mason et al., 2020).

Manual Pushing Technique

Rietveld, Togni, & Vegter, 2025, reports that they reached a consensus that manual wheelchair uses who engage in propulsion with a low push frequency, smooth movement, low peak force and large push angels are things that can support in reducing shoulder injuries.