North Vancouver

Medial Tibial Stress Syndrome

THE NEW “SHIN SPLINTS”

By Jenn Turner.

Many runners and athletes are very familiar with the term shin splints, and may have experienced this injury first hand. In the past “shin splints” was used as a catch-all term to describe a number of different injuries to the bones and muscles of the lower leg, usually describing a specific overuse injury that produces pain. Now sport medical professionals refer to this injury as Medial Tibial Stress Syndrome (MTSS).

Runners are most commonly affected because they put a lot of stress on the bones and muscles of the lower leg. There are two theories to explain the pain caused in MTSS. The traditional theory is that the muscles attached to the tibia bone, one of the two bones that make up the lower leg, pull on the tibia, causing traction on the periosteum covering of the bone. A newer theory suggests that MTSS is the result of a bone stress reaction that becomes painful. This means that when an athlete increases the stress on the bones, they become stronger by remodelling, which occasionally causes pain. Recent research studies have revealed that no actual inflammatory changes occur within the injured structures, supporting the bone stress theory.

CAUSES OF MTSS

The causes of MTSS include training on hard or uneven terrain. These unforgiving surfaces cause a great amount of stress to the tibia as well as the muscles that attach to it. Improper training or lack of recovery between workouts will eventually lead to damage of the tissues and cause pain and dysfunction. Improper footwear, changes in footwear or worn-out running shoes won’t have as many shock absorption properties and can cause shin pain to appear. Frequently athletes who do develop MTSS have a biomechanical abnormality with the foot or ankle that causes undue strain on the tissues. Patients that have had a previous lower limb injury will be more susceptible to developing MTSS as well, usually because their biomechanics are altered after suffering from a previous injury. According to a group of researchers who looked at the incidence of MTSS, the most likely biomechanical fault was foot pronation (foot rolling slightly to the inside). Pronation is common in runners, and excess pronation forces the muscles in the foot and lower leg to work much harder to absorb the shock as the foot hits the ground. When these muscles fatigue, the bone stress reaction starts to occur

Classic Signs & Symptoms of MTSS

- Dull achy pain along the middle or lower part of the tibia

- Pain present at the beginning of the run then subsides

- Pain is usually present after running

- Pain can become sharp and more constant if training is continued

- Pain is reproduced with toe raises or hopping

- There is no swelling or numbness and tingling

- X-rays are usually normal

TREATMENT OF MTSS

The initial treatment for MTSS or any type of overuse injury is rest. This is not the treatment that any athlete wants to hear, but for MTSS rest is very important. A bone stress injury is a precursor to a tibial stress fracture.

There are other sports that can be done while an athlete has this injury. If you do continue to run, the training volume must be decreased, or you could substitute pool running. Ice and ice massage has been shown to be effective for pain, and are reportedly more effective treatments than corticosteroid injections. Stretching the calf muscles first with the knee flexed and then fully extended will help to reduce the amount of pulling of the muscles on the tibia. Active Release Techniques or massage can assist in breaking up scar tissue in the affected tight muscles. This type of therapy can be successful in decreasing the amount of stress on the muscular attachments to the bone.

It is also important to address any biomechanical faults, often through orthotics, which can reduce the amount of stress on the muscles that absorb shock. Training can be resumed slowly after you’ve been pain free for several days, but you should start back at 50 per cent of your previous intensity and duration to ensure that the injury is healed. If you continue to have pain, you’ll need to get a bone scan or MRI to rule out a stress fracture or other pathology that can mimic symptoms of MTSS.

Dr. Jenn Turner, Moveo Sport and Rehab

Clinic Members