Chapter 3

Transfers and bed mobility of people with lower limb paralysis

This chapter describes how people who are wheelchair dependent transfer and move about in bed. It is not feasible to describe all the ways that people with different levels of spinal cord injuries transfer and move. Instead, the approach taken here is to describe the most common strategies used by people with C6 tetraplegia and thoracic paraplegia. People with C6 tetraplegia and thoracic paraplegia utilize strategies adopted by most people with spinal cord injury. People with C6 tetraplegia are of particular interest because paralysis of the triceps muscles has important implications for movement and because C6 is a common level of spinal cord injury.

The key mobility tasks are sitting unsupported, rolling, moving from lying to sitting and transferring. The most common way of performing each task is described in terms of sub-tasks. Sub-tasks can be thought of as critical steps. The text is supplemented by video clips freely available at www.physiotherapyexercises.com.

Sitting unsupported

Sitting unsupported is important because it is an integral part of transferring and dressing.1–4 It is also used when reaching and grasping for objects while sitting on the front edge of a commode, toilet or wheelchair.⁵ For example, reaching for something in a high cupboard requires moving to the front edge of the wheelchair and reaching upwards and laterally.

The seated position is not inherently stable. It is even less stable when reaching or using the hands to grasp, manipulate and lift objects. Reaching forwards or sideways displaces the centre of mass, causing a tendency to fall. In able-bodied people the tendency to fall is counteracted by trunk and leg muscle activity. Appropriate muscle activity occurs subconsciously in response to proprioceptive feedback about body position. However, patients with spinal cord injury have limited proprioception and are unable to use the legs and trunk to maintain an upright position. Instead, they must adopt alternate strategies.

One strategy is to use upper limb muscles to help stabilize the trunk in an upright position.¹^,⁵^,⁶ The muscles capable of providing trunk stability are the latissimus dorsi, pectoralis and serratus anterior muscles. All these muscles have insertions on the trunk or scapula, and while not normally considered postural muscles, they can take on this role in patients with trunk paralysis. Their importance helps explain why patients with C6 tetraplegia attain a higher level of independence than those with C5 tetraplegia (see Chapter 2). Patients with C6 tetraplegia have reasonable strength in these shoulder muscles but patients with C5 tetraplegia do not. Consequently, patients with C5 tetraplegia have great difficulty sitting unsupported and cannot normally perform associated mobility tasks.

Patients with thoracic paraplegia and C6 tetraplegia also use compensatory postural adjustments to sit unsupported.¹^,³^,⁷^,⁸ Small postural adjustments are normally used by able-bodied people during performance of seated tasks. For example, when reaching sideways in sitting, able-bodied people laterally flex the trunk and neck away from the direction in which they are reaching. This minimizes sideway displacement of the centre of mass. Patients with spinal cord injury exaggerate postural adjustments to compensate for the loss of leg and trunk muscles. Thus to reach sideways with one arm they abduct the contralateral arm (see Figure 3.1). Similarly, to reach forwards with one arm they reach backwards behind the body with the other arm while at the same time extending the neck.

Figure 3.1 A patient with C6 tetraplegia sitting unsupported with the knees flexed. When reaching to the left the patient makes compensatory postural adjustments with the right arm.

Compensatory postural adjustments do not occur spontaneously. Not surprisingly, patients with spinal cord injury and extensive paralysis of the trunk muscles initially have difficulty sitting unsupported. Patients with C6 tetraplegia have added difficulties because not only do they have extensive leg and trunk paralysis, but they also have upper limb weakness affecting their ability to ‘catch’ themselves when falling. For example, paralysis of the triceps muscles limits the ability to rapidly extend a protective arm and paralysis of the hand muscles prevents grasping stable objects to prevent a fall. With time and practice most learn compensatory postural adjustments enabling unsupported sitting.

Patients with spinal cord injury and extensive trunk paralysis usually find it easier to sit with the knees extended (see Figure 3.2). This is because the paralysed hamstring muscles generate passive tension when the knees are extended. In turn, passive tension in the hamstring muscles generates hip extensor torques which prevent the trunk falling forwards.⁹ Patients will not fall backwards provided they are leaning far enough forward to position the centre of mass of the trunk anterior to the hip joints. This strategy for sitting is dependent on appropriate extensibility in the hamstring muscles. If the hamstring muscles are inextensible the hips cannot flex sufficiently to position the trunk’s centre of mass anterior to the hip joints. Consequently, the patient falls backwards. On the other hand if the hamstring muscles are highly extensible they do not constrain a forward fall (see Figure 3.3). Needless to say, the hamstring muscles can do nothing to prevent a sideways fall.

Figure 3.2 A patient with C6 tetraplegia sitting unsupported with the knees extended. In this position passive tension in the paralysed hamstring muscles helps maintain the trunk in an upright position. The patient is leaning forwards to position the centre of mass of the trunk (circle) anterior to the hip joints. This prevents a backwards fall.

The paralysed hamstring muscles do not generate passive tension when the knees are flexed. Consequently, they cannot help maintain an upright sitting position when sitting over the side of a bed or on the front edge of a wheelchair (see Figure 3.1). It is therefore more difficult to sit over the side of a bed or on the front edge of a wheelchair than it is to sit in long sitting. In addition, some surfaces are more difficult to sit upon than others.³^,¹⁰ For example, cushions which are very compliant (i.e. those filled with gel, air or fluid) are more difficult to sit on unsupported than relatively firm surfaces (see Chapter 13).³

Rolling

Rolling is used to dress and change position at night. It is also a prerequisite for getting from lying to sitting.

Able-bodied people roll by placing the leading arm across the body and using trunk and leg muscles to initiate rotation of the body. Patients with thoracic paraplegia and C6 tetraplegia cannot use trunk and leg muscles, so instead rely solely on the head and upper limbs to roll. They roll by rapidly swinging the arms across the body (see Table 3.1). This generates angular momentum which is transferred to the paralysed lower segments of the body, facilitating rotation. The position of the legs and head influence the ease of rolling. Most patients have less difficulty rolling if the ankles are crossed and the head is lifted off the bed. Rolling is also easier if the trunk is slightly stiff with loss of passive rotation.

Table 3.1

A patient with C6 tetraplegia rolling onto the side (some practice strategies are described)

	Sub-task	Practice strategies
Figure 3.4a	1. Pre-swing: The head and both arms are rotated away from the direction of the roll.	Practice of this sub-task can be made easier if: • a small weight is placed in the hands • elbow extension splints are used
Figure 3.4b	2. Swing: The head and both arms are thrown across the body.	• a pillow is placed behind the trunk • the ankles are crossed • the leading hip is supported in 45° flexion • elbow extension splints are used

Patients with C6 tetraplegia have added difficulties rolling because paralysis of the triceps muscles limits their ability to maintain elbow extension. Without appropriate strategies, the elbows flex as the arms move across the body and patients may hit themselves in the face. This is avoided by externally rotating the shoulders, minimizing shoulder flexion, and performing the whole task with sufficient speed to ensure the elbows have little opportunity to flex. Contrary to what some may intuitively think it is not possible to roll with the elbows fully flexed. The shortened upper limbs cannot generate sufficient angular momentum to roll the body, and hand position limits arm swing.

Patients unable to roll in bed can use bed rails or loops attached to the side of the bed to pull themselves from side to side. Alternatively, they must rely on assistance from others.

Lying to long sitting

The ability to move from lying to long sitting is an essential part of dressing and transferring. However, the widespread use of electric beds which move patients into sitting has lessened the importance of attaining independence with this task.

Two strategies are used to move from lying to sitting. One involves rolling on to the side and then sitting up from a side-lying position (see Tables 3.2 and 3.3). This approach is cumbersome but relatively easy. Paralysis of the triceps muscles adds complexity because it limits the ability to push down through the hands to lift the body. Patients with C6 tetraplegia overcome this problem by maintaining the side-lying position and ‘walking’ one or both elbows around the body towards the knees (see Table 3.3, Figure 3.6e). From this position, the top arm is hooked under the top leg to pull up into sitting.

Table 3.2

A patient with paraplegia moving from lying to sitting (some practice strategies are described)

	Sub-task	Practice strategies
Figure 3.5a	1. Rolling onto the side: see Table 3.1.	Practice of this sub-task can be made easier if: • see Table 3.1
Figure 3.5b	2. Lifting the upper trunk off the bed: The left arm is horizontally abducted and weight is borne through both hands.	• a pillow is placed under the chest • the sub-task is practised in reverse
Figure 3.5c	3. Moving into the upright position: The elbows are extended.	• a pillow is placed under the chest • the sub-task is practised in reverse

Table 3.3

A patient with C6 tetraplegia moving from lying to sitting (some practice strategies are described)

	Sub-task	Practice strategies
Figure 3.6a	1. Rolling onto the side: see Table 3.1.	Practice of this sub-task can be made easier if: • see Table 3.1
Figure 3.6b	2. Lifting the upper trunk off the bed: The left arm is horizontally abducted and weight is borne through the left elbow.	• a pillow is placed under the chest • the sub-task is practised in reverse
Figure 3.6c	3. Supporting the upper trunk: The right hand is placed on the bed to help prevent a forward collapse of the trunk. Alternatively, both elbows are placed on the bed. (The top arm can bear some weight even though the elbow is flexed and the triceps muscles are paralysed.)	• a pillow is placed under the chest
Figure 3.6d	4. Positioning the top hand under the leg: The right wrist is extended and hooked behind the right knee.	• a pillow or block is placed under the left elbow (see p. 140, Figure 7.1b)
Figure 3.6e	5. Shuffling the bottom elbow around the body: The right arm is adducted with the wrist anchored behind the knee. This momentarily removes weight from the left elbow. At this instant the left elbow is shuffled a small distance towards the feet. This procedure is repeated several times to ‘walk’ the left elbow up towards the knees. (see p. 139, Figure 7.1 for a variation of this sub-task)	Practice of this sub-task can be made easier if: • a pillow or block is placed under the left elbow (see p. 140, Figure 7.1b) • the sub-task is practised in reverse
Figure 3.6f	6. Moving into the upright position: The right arm is adducted with the wrist anchored behind the knee. The left arm is abducted. The action at both arms pulls/pushes the trunk into the midline.	• a pillow or block is placed under the left elbow (see p. 140, Figure 7.1b) • the sub-task is practised in reverse

Another strategy for moving from lying to sitting involves using the upper arms to push directly into sitting from the supine position (see Figure 3.7). Patients with paraplegia place the hands behind the body. They then push down through the hands and use elbow extension to lift the trunk. Paralysis of the abdominal muscles makes it difficult to initially position the hands behind the body. Patients with C6 tetraplegia can also move directly from the supine position into sitting; however, a different technique is used which requires awkward positioning of the shoulders. Consequently, few patients master the technique and it often causes shoulder pain. It is therefore probably best avoided.