When Pain Doesn’t Make Sense: Understanding Repetitive Strain Injuries
Most people associate muscle or joint pain with some type of trauma or accident. This type of injury is classified as a traumatic injury, and, although unfortunate, at least makes sense to most people. The pain can be linked back to some incident or event. However, many people come into our office complaining of pain but they cannot pinpoint what they did to cause the problem. It seems to have arisen out of nowhere, or at best after a seemingly routine activity that they have performed hundreds of times before.
This type of presentation is actually very common, and more often than not what the patient is experiencing is a type of injury known as a “repetitive strain” or “overuse injury.” To best understand these types of injuries realize that any muscle or joint injury occurs through one simple principle, the load (i.e. the physical stress or strain) placed on the body exceeds the capacity to tolerate that load. With traumatic injuries such as an ankle sprain, muscle tear, or broken bone this overload happens all at once, usually as a result of some type of collision, trauma, or moment of intense exertion. However, with a repetitive strain injury (RSI) the stress and tissue damage occurs slowly over time as the body is exposed to a large number of smaller, repetitive forces over weeks or months – hence the term “repetitive strain injury.”
For example, think of a distance runner. With each stride muscles must contract to propel the body forward and dissipate the impact forces associated with each foot strike. Although the loads associated with each individual stride are well within the tolerance level of the musculoskeletal system, the repetitive application of these loads can produce a combined fatigue effect over time, resulting in a reduction of the body’s capacity to endure the forces generated with each stride. Keep in mind that this fatigue effect occurs over the course of weeks and months, not just with each run. At some point, amount of tissue damage will accumulate and the body`s resistance to injury will be compromised. At some point the cycle reaches a critical limit, resulting in pain and injury.
This same pattern occurs in occupation setting as well. Take people who work and sit in front of a computer all day long. While sitting and typing seem like low level activities the muscles of the spine and shoulders are put in a position of sustained contraction as they must be active to support the body and maintain posture all day long. This sustained contraction restricts blood flow and creates a hypoxic/oxygen deficient cellular environment, creating tissue damage and eventual overload. Just like the distance runner, as this pattern continues day after week after month the system become compromised and will eventually become symptomatic.
Resolving Repetitive Strain Injuries
Repetitive strain injuries represent tissue damage and a compromise of the body to properly perform certain activities in a safe and effective way, and therefore, need to be managed properly. Generally, management of RSI`s can be broken down into two main goals. First, attention must be given to the damaged/injured tissue itself. Similar to traumatic injuries, action must be taken to help control any pain and inflammation as well as to promote proper healing of the injured tissue, but with RSI’s attention must also be focus on reducing scar tissue.
This is a critical element of resolving RSI’s because as soft tissues such as muscle, tendons, and ligaments are subjected to repetitive overload the body responds by laying down new connective tissue into the area in an attempt to strengthen and stabilize the area (this does not happen with traumatic injuries as the overload happens so quickly). Over time this scar tissue (also known as soft tissue adhesions or fibrosis) will build up and compromise the strength, flexibility, and blood flow to the area. This scar tissue needs to be treated in order to restore the proper health and function of the tissues. Scar tissue does not respond well to stretching or strengthening exercises or modalities such as ultrasound or laser, but it does respond will to some specific hands-on soft tissue treatment techniques. I have found that Active Release Techniques (ART) treatment is invaluable in treating scar tissue and I would not want to have to try to treat a RSI without using this technique (check out this link to learn more about ART).
The second goal in successfully treating RSI’s is addressing the underlying cause, or source, of the overload. When treatment is only focused on getting the painful tissues to heal the pain may go away for a while, but as soon as the patient resumes their normal activities the problem is in all likelihood going to come back. In some cases, particularly with occupational injuries that demand the patient work at a computer or perform a certain task this may involve simple strategies to reduce the amount of load or at least the repetitive application of that load – addressing the ergonomics of a person’s workstation, improving posture, or adding micro-breaks are a few basic examples. However, in most cases the key to long term resolution in improving the efficiency and effectiveness of how the body moves..