Shin splints and a stress fracture might both be responsible for pain in the lower leg, but the distinction between these conditions is sometimes poorly understood. A stress fracture is a specific condition in which tiny cracks form in the bone. The term "shin splints" refers to lower leg pain, particularly running along the length of the shin, without specifying the source of the pain or the tissues affected. Several diagnoses, including that of a stress fracture, often fall under the catchall label of shin splints.
Pain that runs down the length of the tibia or shinbone is commonly described as shin splints, and a stress fracture might very well cause these symptoms. Most commonly, pain results from medial tibial stress syndrome, a condition that is not fully understood but seems to arise from inflammation of muscles and tendons attached to the tibia. Exercise-induced compression syndrome, in which muscles expand during exertion, and the increased pressure causes pain, might cause shin splint pain. There are other causes for shin splints and a stress fracture might also be responsible.
Medial tibial stress syndrome is usually triggered by overexertion, but running in poor footwear or over uneven terrain can exacerbate the condition. Pain runs the length of the shin, along the inside rather than the front, at its worst during exertion and easing with rest. In severe cases, rest is required to allow the leg to heal, but in other cases, icing and stretching might ease symptoms sufficiently. Good arch support is also recommended.
Exercise-induced compression syndrome occurs when pressure inside the muscle increases. During times of exertion, blood floods into the muscle to provide more oxygen and remove fatigue toxins. Fascia, the tissue covering muscles, is flexible, and this is not normally a problem for most people, but if the muscle swells enough, the fascia cannot stretch sufficiently, and the pressure causes pain, often accompanied by sensations of tightness or tingling. Symptoms ease quickly with rest, but surgery might be required to effectively treat the condition.
Stress fractures are microscopic cracks in the bone, appearing over time when the bone is placed under repeated stress, such as with running. They are often confused with other types of shin splints and a stress fracture can be difficult to diagnose. Swelling might be present, and pain is similar to that experienced with medial tibial stress syndrome. Even with X-rays, the fractures are often too small to see.
Rest, stretching and ice are all effective in recovering from shin splints and a stress fracture is no exception. Stress fractures might, however, respond differently to pain medication. Research indicates that using nonsteroidal anti-inflammatory medications such as ibuprofen might slow the healing of stress fractures, and such medications should not be taken for pain relief when stress fractures are suspected.