Repetitive strain injury (RSI)
What is repetitive strain injury?
Repetitive strain injury, also known as RSI and repetitive motion disorder, is a term for damage to tissues caused by repeated physical actions. These actions are often work-related, such as typing or performing manual labor, and the tissues affected are often in the upper body.
- Carpal tunnel syndrome
- Tendonitis in the wrist and hand
- Tenosynovitis, which affects the sheath surrounding a tendon
- Bursitis in the wrist, knee, elbow or shoulder
- Tennis elbow, also known as lateral epicondylitis
- Cubital tunnel syndrome
- Ulnar tunnel syndrome, also known as Guyon canal syndrome
- Trigger finger or trigger thumb
People with these conditions experience symptoms ranging from a gentle ache to sharp pain that limits their ability to work and perform everyday actions.
Repetitive strain injuries usually affect people of working age. Because of the range of conditions and injuries involved, it is difficult to accurately gauge prevalence. However, the Centers for Disease Control and Prevention estimates that carpal tunnel syndrome affects around 1.9 million people in the United States.
With appropriate treatment, repetitive strain injuries will recover over a period of several months, depending on their severity. Some injuries, particularly those which cannot be mitigated by changes at work, may persist.
Symptoms of repetitive strain injury
- Loss of sensation
- Burning sensation
- Sharp pain
- Shooting pain
- Difficulty moving certain fingers
Body parts commonly affected by repetitive strain injuries include:
Causes of repetitive strain injury
The common factor among repetitive strain injuries is repeated movements in body parts, particularly in the upper limbs. The tissues in these body parts become worn and damaged with overuse. Repeated stresses and strains cause small tears and signs of degeneration which, over time, create symptoms in the person with the condition.
Repetitive strain injuries can be caused by:
- Small, frequent movements
- Vigorous movements containing a lot of force
- A lack of movement, such as holding a limb in an unnatural position
- Using a jackhammer or other vibrating power tool
- Bending the neck to hold a phone handset
- Holding tools with small/narrow handles, such as sewing needles or knives
- Holding tools that are too large
- Stretching and twisting, such as painting or cleaning
- Lifting heavy loads, such as boxes, or people in a healthcare environment
- Gripping a steering wheel
- Performing the same action repeatedly, such as scanning items at a checkout
- Holding limbs without support, such as typing with no wrist support
- Sitting in a cramped position for extended periods of time
See this resource about back pain for more information about pain in the lower back.
Type 1 and Type 2 repetitive strain injuries
Repetitive strain injuries are divided into two categories.
Type 1 RSI is where the symptoms can be categorized as a specific condition, such as carpal tunnel syndrome or tennis elbow.
Type 2 RSI, or diffuse RSI, is where the symptoms are not easily recognized as a specific condition. Symptoms may be poorly defined or shifting, with few or no visible or measurable signs, such as swelling or nerve damage.
Carpal tunnel syndrome
The carpal tunnel is a narrow passageway in the wrist made up of ligament and bone. The median nerve, which runs from the forearm into the hand, passes through the carpal tunnel. Carpal tunnel syndrome is caused when the median nerve becomes compressed or squeezed. If the carpal tunnel or the surrounding tendons swell, it can compress the median nerve. Numbness and pain in the hand can result.
Repetitive strain injury is one possible cause of carpal tunnel syndrome. Repeated hand and wrist movements can irritate the wrist tendons.
For more information, see the resource on carpal tunnel syndrome.
Tendonitis is a condition where tendons, which connect muscles to bone or other body parts, become damaged. Where this damage is caused by overuse, tendonitis can be considered a repetitive strain injury.
There are tendons all over the body and all are capable of developing tendonitis. Areas of the body that are commonly associated with tendonitis include:
For more information see the resource on tendonitis.
Tendons are surrounded by a protective sheath called the synovium. This sheath may become inflamed, resulting in a condition called tenosynovitis.
Tenosynovitis can be caused by injury, infection and overuse. When tenosynovitis is caused by overuse and strain, it can be considered a repetitive strain injury. Any tendon sheath may be affected, but tenosynovitis commonly affects tendons in the:
Trigger finger and trigger thumb
Stenosing tenosynovitis, commonly called trigger finger or trigger thumb, occurs when the sheath surrounding tendons in the fingers become damaged. There are pulleys along these tendon sheaths that help fingers to bend. Stenosing tenosynovitis occurs if the pulley at the base of the finger (the A1 pulley) becomes inflamed or thicker than normal.
Symptoms of stenosing tenosynovitis include:
- Pain when moving the finger
- A popping or catching feeling when moving the finger
- A lump at the base of the finger
- Affected finger becoming locked in a bent position
Stenosing tenosynovitis can be caused by various conditions, such as gout and rheumatoid arthritis, but can also be caused by repeated gripping actions. Where the condition is caused by overuse, it can be considered a repetitive strain injury.
Tennis elbow, also known as lateral epicondylitis, is a form of repetitive strain injury that affects the tendons attached to the outside of the elbow. Overuse or trauma can result in degeneration of the tendon’s attachment, which causes pain.
- Playing racket sports, such as tennis
- Repetitive gripping, such as cutting meat, painting or using a screwdriver
Bursitis is a form of repetitive strain injury that can affect the knee, elbow, wrist or shoulder. When bursitis affects the shoulder, it can also be referred to as a rotator cuff injury.
Prolonged and repeated movement and pressure on the joint can cause bursitis. These movements can include:
- Using picks and shovels
- Raising arms
- Leaning on elbows
Cubital tunnel syndrome
Cubital tunnel syndrome is a form of repetitive strain injury where the ulnar nerve, which travels from the neck to the hand, becomes compressed or irritated at the elbow. Numbness and tingling in the hand and fingers can result, particularly in the ring and little fingers.
Repeatedly stretching or bending the elbow, or keeping the elbow bent for long periods of time, can cause the ulnar nerve to become compressed.
Ulnar tunnel syndrome
Ulnar tunnel syndrome, also known as Guyon’s canal syndrome, is a form of repetitive strain injury where the ulnar nerve becomes compressed at the wrist. The ulnar tunnel, or Guyon’s canal, is a canal in the wrist which the ulnar nerve passes through. If the ulnar nerve is compressed at the wrist, numbness and tingling in the ring and little fingers can result.
Ulnar tunnel syndrome is less common than cubital tunnel syndrome. It is most often caused by a benign cyst, but can also be caused by repetitive movement or pressure to the hand. Activities that can cause such pressure include:
- Gripping a bicycle handlebar
- Using a jackhammer or other vibrating power tool
Diagnosing repetitive strain injury
There is no specific test to diagnose repetitive strain injury as the condition takes many forms. A complicating factor is that some conditions, such as carpal tunnel syndrome, can have several causes.
Repetitive strain injuries are diagnosed by taking a medical history and performing a physical examination. Symptoms may be the result of other conditions, and diagnostic tests may be ordered, such as:
- Blood tests, to check for diabetes or inflammatory joint disease
- X-rays, to check for arthritis or fractures
- Nerve conduction studies (NCS). This test checks the function of nerves by applying small electrical currents and recording how well the nerve conducts electricity. The test causes a mild tingling and is not painful.
- Electromyography, also known as Needle EMG. This test checks the function of muscles by inserting small needles to measure electrical signals. There may be a small amount of pain or discomfort during this test.
- Scans. Medical imaging can reveal whether a condition is suitable for surgical treatment.
Treatment for repetitive strain injury
Treatment for repetitive strain injuries generally follow the same guidelines, whatever the cause or location of the injury. There is some discussion about which treatments are effective, but none are actively harmful.
Stopping the activity which has caused the repetitive strain injury gives the body tissue time to heal itself. If this is not possible, for example where the activity is part of a job, discussions should be had with the employer about changing work patterns or modifying equipment.
Painkillers can be helpful in the short term for repetitive strain injuries.
Non-steroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, can help manage pain. NSAIDs are available over the counter or can be prescribed by a medical professional, but carry risks when used in the long term. NSAIDs may be helpful for bursitis, which is caused by inflammation of a bursa.
For more information see this resource on ibuprofen.
There is some evidence that other painkillers, such as paracetamol, can also be helpful in managing pain.
Corticosteroid injections into the site of the repetitive strain injury can provide short-term pain relief. Injections are administered by a medical professional and can provide relief for up to 48 hours.
Steroid injections have few side effects, but may briefly worsen the pain. They work by directly reducing inflammation at the site of the injury. Steroids should not be taken for long periods of time as they can damage tissues.
Wearing a brace or splint can prevent further pressure on the affected body part and allow it time to heal. A brace may be helpful for repetitive strain injuries such as cubital tunnel syndrome, carpal tunnel syndrome and ulnar tunnel syndrome.
Surgery is an option for repetitive strain injuries which do not respond to non-surgical treatment or cause particular pain and disruption.
Surgery may be helpful for severe cases of carpal tunnel syndrome, tennis elbow and cubital tunnel syndrome. These surgeries are performed as outpatient procedures.
Carpal tunnel release surgery
Surgery for carpal tunnel syndrome is performed as a day procedure under local anaesthesia. The ligament that forms the top of the carpal tunnel is cut, creating more space for the nerve and releasing pressure. Symptoms should disappear over time, though severe cases may not be completely cured.
Therapy to strengthen and improve mobility in body tissues may be helpful for repetitive strain injuries such as tennis elbow and bursitis. A physiotherapist can identify the best exercises for a particular injury and demonstrate how to perform each exercise so as to minimize the risk of further damage.
Physiotherapy will be recommended after any surgery.
Cooling the affected area with ice is a common home remedy for repetitive strain injuries. Ice can numb the skin and provide short-term pain relief. However, there is a lack of evidence to show whether using ice is helpful for long-term tissue repair.
Preventing repetitive strain injury
Repetitive movements are the main cause of repetitive strain injuries, so taking steps to prevent the injury or stopping it getting worse is important.
Many repetitive strain injuries happen at work, and workplaces should be equipped to do an ergonomic assessment of the work environment. Ergonomics is the study of how people interact with objects and their surroundings in the safest way.
- Using wrist rests or adjusting a computer keyboard for typing
- Adjusting a chair and desk, so feet rest flat on the floor
- Taking breaks from repetitive tasks
- Using padding, gloves or special coatings to reduce vibration from power tools
- Using a headset for prolonged telephone use
- Maintaining good posture
- Avoiding standing or sitting in one position for long periods of time
- Using less force when carrying out tasks
The National Institute for Occupational Safety and Health has a step-by-step guide to evaluating and addressing workplaces for ergonomic best practices.
Repetitive strain injuries can also be caused by playing sport or taking part in hobbies. Preventative measures can include:
- Doing warm up exercises before playing sport
- Changing equipment, such as a tennis racket with a properly fitted grip and flexible strings
- Improving or changing technique
- Being aware of ergonomic factors in the home and with hobbies
- Taking regular breaks from repetitive movements during activities such as knitting or woodworking
Repetitive strain injury FAQs
Q: Can I get compensation for repetitive strain injury?
A: Repetitive strain injuries are often caused by poor practices in the workplace. Whether your workplace is liable to pay compensation will depend on the extent of the injury, how severely it affects your activities and whether the employer took steps to prevent the injury.
Q: Is repetitive strain injury permanent?
A: Repetitive strain injury can be cured with appropriate treatment, which may range from rest to surgery. Some severe cases may not be entirely cured. Effective treatment should be complemented by changing the activity that caused the injury. (See Treatment for repetitive strain injury above.)
Centers for Disease Control and Prevention. “Work-Related Musculoskeletal Disorders and Ergonomics.” February 2018. Accessed April 30, 2018. ↩ ↩
OrthoInfo. “Ulnar Nerve Entrapment at the Elbow (Cubital Tunnel Syndrome.” September 2015. Accessed April 30, 2018. ↩
Michigan State University. “Electromyogram (EMG) and Nerve Conduction Study (NCS).” Accessed April 30, 2018. ↩
Arthritis Research UK. “What are steroid injections and why are they prescribed?” Accessed April 30, 2018. ↩
US National Library of Medicine. “Is ice right? Does cryotherapy improve outcome for acute soft tissue injury?” February 2008. Accessed April 30, 2018. ↩