Curbs - The following prerequisites are needed to negotiate differences in height, or vertical obstacles, such as curbs between streets and sidewalks, irregularities in sidewalks, elevated thresholds, weather stripping in doorways, etc. In general, the lower the lesion and the greater a patient's strength, the higher a curb he/she can learn to negotiate.

1. Physical and Skill Prerequisites
   • Greater than normal strength in the anterior deltoids and strength in the infraspinatus, teres minor to ascend curbs
   • Some strength in the trapezius, middle and posterior deltoids, and in the biceps, brachialis, and/or brachioradialis to ascend and descend curbs
   • Some strength in the pectoralis major, teres major, the triceps, and hand musculature to descend curbs in wheelie position; some strength in these muscles to ascend and descend curbs backwards is not required, but is helpful
   • Normal range of motion in scapula abduction and adduction, shoulder extension and internal rotation, and elbow flexion and extension to ascend and descend curbs
   • Normal range of motion in scapular downward rotation and in shoulder flexion and external rotation to ascend curbs; normal range in finger flexion to descend curbs in a wheelie
   • Ability to position trunk in wheelchair, propel wheelchair over even surfaces, and:
     • Lift casters from floor, pop them at edge of curb, and ascend curb, to ascend curb using strength, or,
     • Lift casters off floor, pop them on curb while chair moves forward, and ascend curb, to ascend curb using momentum
     • Control rear wheels and lower caster by turning chair, to descend curb backward
   • Ability to assume wheelie, glide forward, and descend curb to descend curb in wheelie position

2. Functional Skills
   • Ascend from Stationary Position - To perform this skill, which requires less space, skill, and timing, but more strength than ascending using momentum, the patient:
     • Approaches the curb head on and stops a few inches short of the curb
     • Starts with the hands well back on the handrims and pulls forward forcefully and abruptly to lift the casters onto the curb, throwing the head back at the same time as the pull if necessary
     • Backs the chair until the casters are at the edge, places the hands well back on the handrims, and pulls forward with enough force, while throwing the trunk and head forward, for the chair to ascend the curb
   • Ascend Using Momentum - To perform this skill, which requires finesse (rather than strength) and momentum, is faster, and enables higher curbs to be ascended than ascending using strength, the patient approaches the curb head on and with speed. At the last possible moment and without losing speed, he/she reaches back and forcefully and abruptly pulls forward on the wheels to pop the casters up onto the curb, throwing the head back at the same time as the lift, if necessary. The patient times the lift of the casters onto the curb with the moment the rear wheels hit the curb, enabling momentum to carry the chair up onto the curb.
   • Descend Backward - To perform this skill, which is more appropriate for lower curbs, the patient:
     • Backs the chair to the edge of the curb, and, as the wheels pass the edge of the curb,
     • Leans the head and trunk forward to prevent tipping, and applies resistance to the handrims to control the motion of the wheelchair as it descends
     • Rolls the casters straight back off, if the curb is low enough that the footplates will not catch on the curb, or, turns the chair in a tight arc until the casters move past the curb and descend safely to the lower surface
   • Descend in Wheelie - To perform this skill, which is faster then descending backward and enables negotiation over rough terrain, such as gravel or sand, but requires good hand function, the patient:
     • Pops into and glides the wheelchair in a wheelie position as it approaches the curb
     • Maintains the wheelie position and lets the handrims slide through the hands for control, as the wheelchair descends the curb