Shin Splints, Causes and Symptoms
Shin splints are defined as damage to one or more areas along the shinbone that causes pain. One of the most common sports injuries, they are often associated with runners or any athlete who has repetitive strain on the muscles in this area. As the tendons around the tibia, or shinbone, become inflamed, they can cause pain. This pain usually occurs on the inside of the shin. Shin splints account for approximately 17% of all running injuries.
While this injury can happen to anyone, it tends to occur nearly twice as often in women. This is thought to be because women have lower bone mass density and can injure themselves more easily. People who have flat feet are also especially prone to this condition because of the added shock they put on the bones with each step while running or changing direction. While treatment of shin splints typically requires rest and ice, without seeing a doctor, the condition can worsen and lead to more severe injuries. Shin splints need to be differentiated from stress fractures or other conditions by an orthopaedic surgeon.
Anatomy of the Shin
The shin is the lower part of the leg, between the knee and the ankle. It consists of the following:
- Tibia (the larger shinbone)
- Fibula (the smaller shinbone)
- Tibialis Anterior (muscle)
- Tibialis Posterior (muscle)
Types of Shin Splints
Shin splints are typically divided up into two main types of injury:
- Anterior shin splints – This type of shin splint occurs in the tibialis anterior. The tibialis anterior is the muscle that is used to lift the foot up and is covered by a thin sheath. When a person walks and rotates their foot outward, it causes the muscle to rub along the sheath, creating irritation. Over time, the pain worsens whenever weight is put on the foot and without treatment, this can lead to the muscle detaching or to a stress fracture.
- Posterior shin splints – These injuries occur in the tibialis posterior, which is the muscle that runs from the foot up the back of the leg to the knee. It is the muscle that is responsible for pointing the toes. When a person pronates as they walk, they cause the muscle to twist gradually. This can lead to the muscle detaching or a stress fracture if left untreated.
Causes of Shin Splints
There are a few causes of shin splints:
- Overuse of the muscles – When a person runs or plays a sport that requires them to change directions quickly, they put a lot of strain on this muscle group. As this strain builds up, the muscles begin to twist and rub. That eventually leads to irritation and causes the nerve endings in the leg to become inflamed.
- Muscle Imbalance – As the body begins increased physical activity, it needs time to allow muscle groups to catch up and work in tandem with each other. Core muscles are some of the last to develop and a weakened core can mean more pressure put on the lower extremities, including the shinbone. When this happens, people can experience shin splints as their muscles strengthen.
- Tightness in the shin muscles – If a person does not stretch properly, it can lead to tighter shin muscles that ultimately cause more friction and stress, leading to the pain associated with shin splints.
Symptoms of Shin Splints
Symptoms of shin splits always include some level of pain due to the number of nerve endings in and around the muscles that connect to the bone.
The following are common shin splint symptoms. Depending on the way in which this injury was incurred and how physically strong a person is, symptoms can vary:
- Tenderness or pain along the inside of the shinbone
- Slight swelling
- Pain at the beginning of exercise
- Pain at the end of exercise
- Pain as toes are pointed
Shin splint symptoms occur because the muscles around the shinbone become inflamed. While this injury is minor and can be treated easily, without treatment or the help of an orthopaedic surgeon, it can lead to more significant injuries down the road, such as muscles detaching or stress fractures.
The multidisciplinary team of orthopaedic experts at North Shore-LIJ Orthopaedic Institute's Trauma Services in New York treats Shin Splints as well as a broad range of conditions that affect the bones within the body.