Table 1 Participants, interventions, comparison and outcome measures of all studies and quality score STROBE checklist

[49]

Bernard et al.

Six SCI T4-8 (high), six SCI T11-L5 (low) and six AB

Perturbation on moving platform for wheelchair

High SCI, low SCI, AB 4 oscillation levels

Damping factor of head

4

Moderate-poor

[29]

Boswell Ruys et al.

30 SCI C5-L2 AIS-D, 14 high level and 16 low level

Upper body sway = sit still unsupported for 30 s

Maximal balance range forwards and backwards

Coordinated stability = follow track with pencil by adjusting trunk position in bending and rotating.

New (<1 year post injury) vs. old (>1 year post injury

High level = C6-T7 AIS A vs. low level = T8-L2 AIS A or incomplete AIS B-D with abdominal innervation

Reliability and validity of the tests

15

High

Alternating reach test = tapping table eight times fast with and without arm support

Seated reach distance lateral left and right

Upper body dressing

[30]

Chen et al.

Eight SCI T1-6 (high thoracic)

22 SCI T7-12 (low thoracic)

Sitting stability static (unsupported 30 s) and dynamic (30 s maximum leaning to four sides)

Time needed for functional activities: upper body dressing, lower body dressing and transfer.

Low versus high thoracic SCI

Trunk strength (hand held dynamometry), lesion level and trunk length in relation to sitting balance.

CoP displacement static and dynamic (sum score for all directions)

Time to complete functional tasks

16

High

Sitting balance in relation to functional tasks.

[31]

Curtis et al.

Seven athletes with spinal cord injury; four in IWBF class 1 and three in IWBF class 2, nine AB

Reaching in sagittal and transverse plane

IWBF class 1 and 2, AB

Belt at thigh and trunk versus no belt

Reaching distance in sagittal and transverse plane

16

High

[50]

De Abreu et al.

11 SCI T2-L2, AIS A-C, six AB

Reaching in anterior-posterior direction seated on different cushion types

AB versus SCI

Different cushion types

Maximum reach

Anterior displacement of the trunk

Reaching time for 50%, 75% and 90% and maximum reach

13

Moderate-poor

[32]

Gauthier et al.

15 SCI: 9 “Abdo” (levelT7 or lower or active contraction abdominals to generate trunk flexion) 6 “No Abdo” (level higher than T7, no active contraction abdominals to generate trunk flexion)

15 AB

Move CoP to eight directions with 45^° interval

AB vs SCI “Abdo” versus SCI “No Abdo”

OSI (Overall Stability Index)

DSI (Direction Specific Index of Stability)

17

High

[51]

Harel et al.

Seven SCI T1-T11 AIS A-B

Seven AB

Static balance with eyes open (EO) and eyes closed (EC)

Dynamic balance: leaning in multiple directions

AB versus SCI

Sitting items Berg Balance Scale

Modified functional reach test

14

Moderate-poor

Seated posturography: postural sway EO and EC

Maximum excursion centre of gravity (CoG) and directional control

[33]

Janssen-Potten et al.

Ten SCI T2-8 (high)

Ten SCI T9-12 (low)

Ten AB

Bimanual forward reaching task 15%, 30%, 75% and 90% of maximum

Standard chair (S)

7° tilt (7 T)

12° tilt (12 T)

22° recline (22R)

Maximum reaching distance

CoP displacement

14

Moderate-poor

EMG erector spinae T3, erector spinae T9, erector spinae L3, latissimus dorsi, trapezius pars ascendens, pectoralis major, serratus anterior, oblique abdominal muscles

Reaction time and movement time

[33]

Janssen-Potten et al.

Ten SCI T2-8 (high)

Bimanual forward reaching task 90% of maximum

High and low SCI

CoP displacement

15

High

Ten SCI T9-12 (low)

Standard chair and 10° forward inclination

EMG erector spinae T3, erector spinae T9, erector spinae L3, latissimus dorsi, trapezius pars ascendens, pectoralis major, serratus anterior, oblique abdominal muscles

Kinematics pelvis (tilt)

Ten AB

[34]

Janssen-Potten et al.

Ten SCI T9-12 (low T)

Ten SCI L1-5 (L)

Ten AB

Bimanual forward reaching task 90% of maximum

Low T, L and AB

With and without rigid footrest

Maximum displacement CoP (CoP max)

Movement time

15

High

EMG erector spinae T9, erector spinae L3, rectus abdominis, oblique abdominals, gluteus max, tensor fascia lata, rectus femoris, vastus lateralis, biceps femoris, semitendinosus, tibialis anterior, gastrocnemius medialis

[35]

Kamper et al.

Four SCI C5-7 (tetraplegia)

Four SCI T2-9 (paraplegia)

Five AB

Tilting movement in frontal plane on servo controlled platform in standard WC

Tetraplegia-paraplegia-AB

And tilting movements with high and low amplitude and acceleration

Balance loss

FLCP = fraction of limit of CoP movement

Velocity of CoP displacement

Kinematic data

Kinetic data (torque of pelvis, lower trunk and upper trunk)

17

High

[36]

Kamper et al.

Four SCI C5-7 (tetraplegia)

Four SCI T2-9 (paraplegia)

Five AB

Tilting movement in sagittal plane on servo controlled platform in standard WC

Tetraplegia-paraplegia-AB

And tilting movements with high and low amplitude and acceleration

Balance loss

FLCP = fraction of limit of CoP movement

Kinematic data

17

High

[52]

Kerk et al.

Six SCI T3-6, absent abdominal muscles

Sub maximal and maximal exercise test on wheelchair roller in own WC

With and without elastic abdominal binder

Pushing stroke parameters, physiologic parameters, trunk movement

12

Moderate-poor

[37]

Potten et al.

Ten SCI T2-8 (high)

Ten SCI T9-12 (low)

Ten AB

Bimanual forward reaching task 15%, 30%, 75% and 90% maximum

High SCI, low SCI and AB

CoP displacement

EMG serratus anterior, m. pectoralis major, latissimus dorsi, erector spinae T3, trapezius pars ascendens

16

High

[53]

Requejo et al.

Five SCI T4 and higher (high), five SCI T12 and lower (low)

Three pushing speeds (0.85, 1.03 and 1.21 m/s) and one self-selected speed, administering frequent small bumps

Low and high SCI, wheelchair with rear suspension (three types), and without rear suspension

Self-selected speed

Vertical seat reaction force

Head acceleration

10

Moderate-poor

[46]

Schantz et al.

Four SCI low thoracic, three SCI cervical

Comfortable and maximum pushing speed, maximum acceleration on gymnasium wooden floor

SCI low thoracic and SCI cervical

Maximum velocity and acceleration, EMG activity of arm muscles, trunk position and movement

Reaction time

Movement time

EMG activity latissimus dorsi and trapezius pars ascendens

8

Moderate-poor

[54]

Seelen et al.

15 SCI T4-T12

15 AB

Reaching forward 30%, 60% and 90% of maximum after warning signal with and without cue

SCI and AB

11

Moderate-poor

[55]

Seelen et al.

15 SCI T2-8 (high)

15 SCI T9-12 (low)

Bimanual forward reaching task 15%, 30%, 75% and 90% of maximum

High and low SCI in experiment 1; none (only AB) in 2

CoP displacement

EMG erector spinae T3, erector spinae T9, erector spinae L3, latissimus dorsi, trapezius pars ascendens, pectoralis major, serratus anterior, oblique abdominal muscles

14

Moderate-poor

15 AB

Antero-posterior force component

[56]

Seelen et al.

Five SCI T4-T8 (high), seven SCI T9-T12 (low)

Releasing push button on lap

Reaching forward bilaterally

15%, 30%, 75% and 90% of maximum reach

high and low SCI

duration since SCI

Reaction time

Movement time

13

Moderate-poor

[47]

Seelen et al.

Five SCI T4-8 (high)

Seven SCI T9-12 (low)

Bimanual forward reaching task 15%, 30%, 75% and 90% of maximum

High and low SCI, different points in time

Braced vs. non braced (post hoc)

CoP displacement

EMG erector spinae T3, erector spinae T9, erector spinae L3, latissimus dorsi, trapezius pars ascendens, pectoralis major, serratus anterior, oblique abdominal muscles

13

moderate-poor

[38]

Seelen et al.

15 SCI T2-8 (high)

15 SCI T9-12 (low)

15 AB

Bimanual forward reaching task 15%, 30%, 75% and 90% of maximum

High and low SCI

Reaction time, movement time

CoP displacement

15

High

[44]

Serra-Anno et al.

24 SCI higher than T9 (high); T9 and lower (low)

24 AB

Static sitting balance (ST) with eyes open (EO) and eyes closed (EC)

Dynamic sitting balance (SLT)

High SCI, low SCI, AB

ST: signal amplitude, range, frequency spectrum in anterior-posterior and medial-lateral directions.

SLT: maximum CoP displacement, efficient CoP displacement and normalised total excursion of CoP

13

Moderate-poor

[57]

Shin et al.

Seven SCI T10 and higher (high)

11 SCI T10-L1 (low)

18 AB

Functional reach test: reaching as far as possible with dominant hand

High SCI, low SCI, AB

Functional reach, velocity and CoP trajectory, functional boundary

13

Moderate-poor

[39]

Triolo et al.

Eight SCI low (T5-10) and high (C6-7) with implanted neuroprosthesis.

Seated bimanual reach: 30 in. = desktop and 48 in. = high shelf, loaded (20% of unilateral shoulder flexion strength) lifting a light or an heavier object

High and low SCI Stimulation on and off, Strong and weak based on volitional trunk extension strength with stimulation

Unsupported bimanual reaching distance with and without stimulation.

17

High

[40]

Vanlandewijck et al.

13 track athletes, three female no full trunk function, four male no full trunk function, six male full trunk function. Diagnosis: SCI, spina bifida, arthrogryposis, amputation

Maximum acceleration track and treadmill with 4× resistance

Male athletes full trunk function versus male athletes no full trunk function

Distance on track after 1, 2 and 3 s (m) and distance on ergometer after 1, 2 and 3 s (m)

19

High