Table 7 SCI vs. Able-Bodied Participants

Author Year

Research Design
Sample Size

Methods Outcome

Hobson 1992


Prospective Controlled Trial




SCI group (n=12): Mean Age=40.9 yr; Gender: males=10, females=2; Level of injury: paraplegia=7, tetraplegia=5; Severity of injury: complete; Mean time since injury=19.5 yr.

Able-Bodied group (n=10): Mean age=39.3 yr; Gender: males=6, females=4.

Intervention: Comparison of Pressure mapping and shear measurements from midline neutral posture to eight typical wheelchair-sitting postures (trunk bending left and right, forward trunk flexion 30 and 50 degrees, back recline 110 and 120 degrees and tilt 10 and 20 degrees).

Outcome Measures: Tangentially induced shear (TIS) measuring shear forces; Pressure distribution – Oxford Pressure Monitor Device measuring average and maximum pressure and peak pressures gradient.

1.     Mean maximum pressure was on average 26% higher in the SCI group versus the able-bodied group.

2.     Forward trunk flexion reduced the average pressure for both groups; however, SCI group encountered a 10% increase in pressure at the initial 30° of forward flex before a reduction occurred.

3.     SCI subjects had a mean peak pressure gradient that was 1.5-2.5 greater than able-bodied subjects. Maximum decrease of pressure gradient from a neutral position happened after the backrest reclined to 120°.

4.     When a sitting position change occurred, a similar shift to the anterior/posterior midline location of maximum pressure was experienced in both groups. From neutral, a forward trunk flexion at 30° and 50° produced a 2.4 and 2.7 cm posterior shift. When the backrest reclined to 120°, the greatest posterior shift occurred at 6 cm.

Gutierrez et al. 2004


Case Control




SCI group: Gender: males=25; Level of injury: paraplegia=25; Severity of injury: AIS A=25.

Able-bodied group: Gender: males=8.

Intervention: Posture changes as related to pressure, contact area and symmetry of loading, on a standardized hard surface and for SCI, in their wheelchair as well.

Outcome Measures: Pressure distribution via Tekscan Pressure Mat.

1.     Significant differences were found between the groups. SCI group had increased pressure (p<0.01), decreased contact area (p<0.01) and increased asymmetry (p<0.05).

2.     Sitting in their own wheelchair improved pressure distribution, as compared to the hard surface. Although total seating area force increased (p<0.01), the pressure reduced and the contact area increased (p<0.01).

3.     No improvements occurred when comparing relaxed and upright position in their own wheelchair.