Repetitive strain injuries of the shoulder
Repetitive strain injury is an injury caused by repetitive tasks. Prolonged manual wheelchair use can lead to pain and repetitive strain injury (RSI) of the upper extremities, especially in the shoulders. The number of manual wheelchair users experiencing pain tends to increase with the time spent using a wheelchair. Although manual wheelchairs have improved tremendously over the past 15 years, many people continue to develop arm pain and injury due to repetitive use. Studies have shown that approximately 30 to 50% of persons with paraplegia report shoulder pain that interferes with their mobility.
How it occurs
There are three mechanisms that may lead to shoulder injury in wheelchair users.
- Wheelchair propulsion wears and weakens the rotator cuff (a group of four muscles surrounding and supporting the shoulder).
- Lifting things overhead increases wear and tear on the rotator cuff
- Improper wheelchair transfers or lifting can cause shoulder injury.
Degenerative changes occur from repeated use of the rotator cuff muscles; these changes may include “wear and tear” of the cartilage. The position and the repetitive loading of the shoulder joint for propulsion and transfers most likely contribute to these changes, along with muscle imbalance due to the mechanics of wheelchair propulsion. For wheelchair users, fingers and shoulders tend to be the most common upper-extremity injuries due to a lack of flexibility and/or strength in the shoulder joint. Joint stability at the shoulder depends on muscle strength. If a joint and muscle aren't flexible, they can more easily be strained or sprained.
Signs and symptoms
Signs may include pain during range of motion, especially with overhead activities, transfers or wheeling.
Diagnosis
Your doctor will review the symptoms and examine the injured area. The examination will likely include complete physical exam, including range of motion, flexibility and sensation. The doctor may order further imaging to determine the type of injury.
Specific types of injuries may include:
- Impingement syndrome
- DJD (degenerative joint disease)
- Rotator cuff tear/bicipital tendinitis
- Capsulitis
- Myofascial pain (pain centered around trigger points in muscles)
- Cervical radiculopathy (pinched nerve in the neck region)
Treatment
Treatment may include rest and medications for pain treatment if needed. Compensatory techniques can be taught to reduce symptoms. Medical treatment of specific conditions will vary. It is most important to learn proper posture, weight bearing and weight maintenance. Additionally, there are specific exercises which will help prevent further shoulder injuries. Flexibility and strong muscles are keys to help prevent shoulder injuries. Physical therapy may be useful in treating symptoms and preventing recurrence. Some specific exercises to strengthen the shoulder can also be helpful. These exercises should be performed on a continuing basis to prevent shoulder pain. Stretching exercises should be performed daily, and strengthening exercises performed every other day.
Returning to activity and sports
The goal is the return to sports and higher level wheeling activities as quickly and safely as possible. If the return comes too soon, or an individual pushes through pain, then the injury may worsen, which could lead to chronic pain and difficulty with sports or wheeling. Everyone recovers from injury at a different rate. Return to sport or activity will be determined by how soon the shoulder recovers, not by how many days or weeks it has been since the injury occurred. In general, the longer the symptoms appeared before starting treatment the longer it will take to get better. Individuals should be pain-free with everyday overhead activities, transfers, and wheeling before return to sports. For more information on adaptive athletics visit the Great Lakes Adaptive Sports Association.
Preventing repetitive strain injuries
Avoid gaining extra weight (this puts stress on the joints). It is also important to maintain strength and flexibility. A physical therapist can assist in developing the best, most efficient wheelchair stroke possible — minimizing strokes per minute and doing a smooth semicircular pattern when pushing so when you let go of the hand-rim your hands fall and swing back for the next push. Wheelchair pushups are also an important exercise for pressure relief and transfers. Maintaining a 60-second wheelchair pushup should be part of a daily routine to maintain function.