Overuse Injuries
By Corrine Haddox, PT
Spring is here and everyone is dusting off the running shoes, kayaks and bikes after a long Vermont winter. Unfortunately, the spring also brings the potential for overuse injuries as activity levels increase. How can you prevent a nagging injury from keeping you sidelined this summer? Let’s first discuss what an overuse injury is and how they occur.
Overuse injuries can be defined as a cumulative, repetitive microtrauma that ultimately leads to tissue damage, inflammation and pain. Injuries happen due to a mismatch between the demands on the body and the body’s efforts to adapt to the new or increased demands. This tissue damage can culminate in tenopathies, ligament sprains or even stress fractures. Common overuse injuries include patellar tendonitis, plantarfasciitis, or rotator cuff impingement. The problem is that you don’t usually know that your training is causing injury until it’s too late because this microtrauma happens without much pain initially.
Both intrinsic and extrinsic risk factors contribute to overuse injuries. Extrinsic factors are avoidable and include poor technique, improper equipment or a rapid change in the type, intensity or duration of training. Even a change in training surface can be a factor. For example, changing from treadmill running (relatively soft surface) in the winter to running on a sidewalk (very hard surface) in the spring can cause hip, knee or foot pain.
Intrinsic factors include biomechanical abnormalities, including malalignment of joints, muscle strength/length imbalances, and poor joint stability. A common diagnosis due to biomechanical problems is patellofemoral pain (pain under the kneecap). Patellar pain can be related to a disparity between hamstrings, quadriceps and hip rotator length and strength, resulting in improper tracking of the patella.
Initially, once an overuse injury is diagnosed, the first mode of treatment is rest. Without removing the stress from the tissues, a pain/inflammation cycle will continue and decrease the likelihood of healing properly. The next step is to treat the inflammation directly. Physical therapists use a variety of modalities to treat acute inflammation including ultrasound, electrical stimulation and iontophoresis. There has been some controversy over the past several years over the use of NSAID’s (like ibuprofen or naprosen) in the acute stages of the inflammatory process. Research has demonstrated that the use of ibuprofen in the first several days after an injury can interrupt the body’s natural inflammatory process, and may ultimately cause a state of chronic inflammation. Likewise, the use of injectable or oral corticosteroids is also controversial, and their role is not well-supported by objective data. Doctors typically administer them with caution, because they are thought to decrease collagen production, weaken the tensile strength of tendons, and ultimately result in poorer healing.
Tissue healing involves the growth of new blood vessels and cells that create collagen deposition (scar tissue) and maturation in injured tissue. This process is best accomplished with a combination of site-specific rehabilitative exercise and non- or low impact cardiovascular conditioning, the goal of which is to restore injured tissue to normal or near-normal function. Early exercise enhances oxygen transport to tissues and nutrition, minimizes unnecessary muscle loss, and aligns scar tissue to meet eventual sports-induced stresses.
The next step in treatment would be a complete biomechanical analysis to identify strength or flexibility deficits that may be the underlying cause of the injury. Exercises will be prescribed to address these deficits.
You can decrease your risk of injury by following these recommendations:
- Do not increase running mileage by more than 10% per week.
- Do not run more than 45 miles per week. There is little evidence that running more than 45 miles per week improves your performance, but a great deal of evidence shows that running more than 45 miles per week increases your risk for an overuse injury.
- Do not run on slanted or uneven surfaces. The best running surface is soft, flat terrain.
- Do not "train through pain." Pain is a sign that should not be ignored, because it indicates that something is wrong.
- If you do have pain when you train, place ice on the area and rest for 2 or 3 days. If the pain continues for 1 week, see your doctor.
- Follow hard training days with easy days or take a day off from training.
- Change your running shoes every 500 miles (less if you are a heavy runner). After this distance shoes lose their ability to absorb the shock of running.
- Cyclists should have their position checked by a professional that specializes in bike fit. Improper positioning can cause injury and decrease overall power output.
Progress through rehabilitative programs is best accomplished under the direction of a physical therapist or a certified athletic trainer, since each patient's regimen is based on the particular injury and an athlete's specific needs.
Corrine Haddox is a physical therapist with Timberlane Physical Therapy in South Burlington, VT. She specializes in the rehabilitation of endurance athletes (and tries to be one herself). She is also a member of Green Mountain Multisport Club. She can be reached at (802) 864-3785 or email at corey_haddox@msn.com.