Anterior Compartment Syndrome:
Muscles at the front of the shin are enclosed withing a connective tissue (fascial) sheath known as the anterior compartment. This sheath does not have a lot of flexibility to it. When running, the muscles become "pumped up," filling with blood. This increases the muscles' volume. Given the inflexible nature of the sheathing, pain ensues. Pain classically comes on shortly after the beginning of the run and will reduce significantly after 30 minutes of rest. This condition is often seen in runners that are rapidly building their distance, perhaps because the fascia has not had time to expand with the muscle development. At rest, the muscle is minimally tender to touch. Circulatory symptoms to the foot are possible, such as coldness or tingling/numbness.
Medial Tibial Stress Syndrome:
Pain along the bony shin is most likely Medial Tibial Stress Syndrome (MTSS). The tenderness is thought to be caused by muscle pulling on the outer layers of the bone, causing irritation. Pain is typically present at the beginning of the run, easing as the run progresses. Pain then returns when the runner is at rest, often hours later.
Stress fractures appear very similar to MTSS. Stress fractures are when cracks form in the bone from the heavy demands of running. Pain is felt along the tibia, or shin bone, typically the lower 1/3. Pain is present at the beginning of the run and increases as the run progresses. The bone is tender to touch at rest.
It's crucial to get the diagnosis right as treatment is dependant on the condition. The only way to be sure of your diagnosis is with a thorough examination. X-ray examination may be necessary and we have digital x-ray facilities on site. Seek professional advise from someone experienced in sports injuries.
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