Background

Manual wheelchair propulsion causes shoulder tendon pathologies in wheelchair users with spinal cord injury. Four different wheelchair stroke patterns can cause varying amounts of acute changes in the shoulder tendons.

Objective

To evaluate and compare acute changes in the supraspinatus and biceps tendons and acromiohumeral distance (AHD) after propulsion between different stroke patterns in individuals with spinal cord injury. In addition, to associate tendon changes with demographic and biomechanical characteristics.

Design

Prospective and comparative study between four groups.

Setting

Tertiary rehabilitation hospital.

Patients

Male wheelchair users with spinal cord injury.

Interventions

Participants were divided into four groups according to stroke pattern (arcing, semicircular [SC], single-loop [SL], and double-loop [DL]), in which they used their wheelchair on a motorized treadmill at a speed of 1 m/s. A sample of 40 people was created, 10 in each group. All participants performed a propulsion test.

Main Outcome Measures

Temporospatial variables and shoulder kinematics were analyzed. Supraspinatus tendon thickness (SSTT), long head of biceps tendon thickness (LHBTT), and AHD were measured before and after the propulsion test.

Results

SC pattern had lower cadence and larger contact angle. A reduction in SSTT and LHBTT in arcing pattern, LHBTT and AHD in SC pattern, and LHBTT in DL pattern was observed (all p < .05). However, SL pattern did not differ significantly in all ultrasonographic measurements (all p > .05). Body mass index was associated with a decrease in SSTT. Age and number of daily push-ups were associated with a decrease in AHD.

Conclusions

Fewer tendon changes after the propulsion in the SL pattern suggested that the supraspinatus and biceps tendons were preserved in this pattern. The SL pattern may be a better choice for male wheelchair users with supraspinatus and biceps tendon pathologies.