As more children play organised sport with regular training sessions, stress fractures have become a common overuse injury in adolescents.

Definition: A stress fracture is a small break in the bone. Rather than a typical fracture that occurs as a result of a traumatic incident with immediate pain, a stress fracture develops from repetitive stress or overuse over time. Initially there is a stress reaction and if the activity continues, a fracture can occur.

Weight-bearing exercise that places moderate levels of stress on the bones is a great way to increase bone density. However, if a bone absorbs so much weight and/or impact in a short period of time there is an imbalance and the bone becomes weaker. Tired muscles cannot absorb the force and transfer the stress to the bones. It’s a case of too much, too often, too soon and too fast.

Symptoms: Most stress fractures occur in theweight-bearing bones of the body – the foot, lower leg especially the outer part (fibula) and the pelvis as they need to absorb the forces when walking, running and jumping. But  stress fractures can occur in the shoulder and elbow, for example, brought on by frequent throwing, and in the wrist of a gymnast. Pain deep within the affected area that is increased by activity and eases with rest is a common symptom. There may be swelling and inflammation. The area is tender to touch and the athlete feels the area is weaker.

Causes: The most common cause is a sudden increase in physical activity, increased frequency and/or increased duration. Changing sport, changing to playing on a hard surface, improper technique or poor equipment like worn-out shoes can increase the risk of a stress fracture. Girls are more prone to stress fractures

Investigations: An x-ray may be done, and might not show changes initially but as new bone is laid down the fracture can be seen if the x-ray is repeated later. An MRI, which gives clear pictures and doesn’t use radiation, is usually ordered. A bone scan may be preferred in some cases, and involves the injection of a radioactive substance which will show up the stress fracture.

Treatment: Rest is the key – which of course is always difficult for an active person but it is very important to help the fracture to heal. Stress fractures can take 6 – 12 weeks to repair, so stopping the activity that causes the pain is important. Your foot may be rested in a Cam walker boot or brace and you may be given crutches to reduce the weight on the foot/leg.

Sometimes switching to a lower impact sport can be allowed such as cycling or swimming but this depends on the site of your fracture.

Lower back stress fracture

Lumbar stress fractures are a common cause of lower back pain in adolescence. If back pain continues despite treatment, is worse with activity and pain is recurrent, then a stress fracture should be considered.  Certain athletes are more prone to these injuries, such as gymnasts, rowers and fast-paced cricket bowlers, but they can occur in any running sport. The arching of the back along with the rotation of the spine combine to put stress around an area called the pars, a bone which connects the joints between the vertebrae. This typically occurs around L5 (5^th lumbar spine) – basically the belt line. These fractures develop on one side but can progress to both sides.

Once diagnosed, the athlete will need to stop all exercise and avoid anything that causes pain for about four weeks. If the pain eases while doing normal daily activities during that time, the athlete will then commence physiotherapy under strict guidance. Physiotherapy can include strengthening exercises of the core, water exercises, weight training and stretching of the hamstrings, hip flexors and glutes specifically. The athlete will increase participation gradually until they can finally return to usual sport. In general, the recovery time from a pars stress fracture is approximately 12 weeks. Psychological support and mentoring is important to help support the athlete during these long-term injuries.

Sister Margaret Bates
School Nurse