Movement patterns and muscular demands during posterior transfers toward an elevated surface in individuals with spinal cord injury

Abstract

Study design: Three-dimensional kinematic analysis and surface electromyography (EMG) of 10 male adults with complete spinal cord injury (C7 to L2). Objective: To examine movement patterns and muscular demands in individuals with spinal cord injury (SCI) during posterior transfers. Setting: Pathokinesiology Laboratory at a Rehabilitation Centre, Montreal, Canada. Methods: Kinematic variables that described the positions and angular displacements of the head, trunk, shoulder and elbow were obtained by videotaping markers placed on the subject segments. EMG data were recorded for the biceps, triceps, anterior deltoid, pectoralis major, latissimus dorsi and trapezius muscles of the dominant upper extremity during posterior transfers using surface electrodes. To quantify the muscular demand, the EMG data recorded during the transfers were normalized to values obtained during maximal static contractions (EMGmax). The mean muscular demand was calculated for every muscle during the lift phase of the transfers. The lift phase was determined by pressure-sensitive contacts. Results: All subjects were able to execute the posterior transfers on an even surface, whereas nine subjects completed at least one of the transfers to the elevated surface. A forward-flexion pattern at the head and trunk was observed when either one or two hands remained on the lower surface, whereas a lift strategy was seen when both hands were placed on the elevated surface. Transferring to the elevated surface with hands on the lower surface required inferior electromyographic muscular utilization ratio (EMUR) than the transfer on the even surface for all muscles. The lowest EMUR were calculated for the transfer to the elevated surface with hands on the lower surface (triceps (18%), pectoralis major (53.8%), trapezius (66%) and latissimus dorsi (24.5%)) while performing the same transfer with hands on the elevated surface generated the highest EMUR (triceps (40.2%), anterior deltoid (73.2%), trapezius (83.6%) and latissimus dorsi (55.3%)). Conclusions: Subjects presented different movement characteristics and muscular demands during the posterior transfers. It is suggested that the forward-flexion pattern improves the dynamic trunk stability and reduces the muscular demand required to transfer. High muscular demand developed when hands were positioned on the elevated surface might be due to increased postural control demands on the upper limb and reduced angular momentum.Spinal Cord (2005) 43, 74-84.

Movement strategies during car transfers in individuals with tetraplegia: a preliminary study

“…Several researchers reported that individuals with thoracic SCI have coordinated flexion movement between the head and trunk so as to lift their buttocks. [6][7][8][9] In the present study, one subject (D) showed a similar coordinated flexion movement to lift his buttock. Only subject-D had a higher motor score for upper extremities (Table 1).…”

“…Generally, subjects with tetraplegia have a lower dynamic balance capacity when compared with those with thoracic SCI. 4,5,7,14 Moreover, these two subjects (B and C) had lower capacity for upper extremities (Table 1). These subjects may, therefore, have difficulty in forward inclination of their trunk in order to shift their center of mass forward.…”

“…[4][5][6][7][8] Allison et al 4 investigated the movement patterns of a long sitting transfer in individuals with SCI (8 tetraplegics and 2 paraplegics with lesions from C5 to T10). Their report suggested that individuals with higher level lesions (C7 and higher) selected rotatory patterns that were characterized by an opposite direction movement between the head and pelvis.…”

“…4,5 Additionally, several other studies reported on the kinematic characteristics of posterior long sitting and sitting pivot transfers in individuals with SCI (C7 to L1). [6][7][8][9][10] These studies indicated that the coordinated flexion movement between the head and trunk assist the buttocks to lift off the seat.…”

Elbow problems in paraplegic spinal cord injured patients: frequency and related risk factors—a preliminary controlled study

“…6 During weight-relief lifting activities, high-to-moderate muscular demands were documented on long head of triceps muscle besides latissimus dorsi and sternal pectoralis muscle. 7,8 Although previous reports have explored shoulder injuries in SCI, 3,9-12 the elbow joint, which serves as one of the main biomechanical units during the daily activities of paraplegic patients, has not been substantially evaluated in the relevant literature. In this regard, we believe that our first and preliminary results, of increased TTT and frequency of joint fluid, are noteworthy.…”