Everyone knows the merits of an active lifestyle, but too few recognise the need to take a break when they experience discomfort. After all, as the saying goes, no pain, no gain, right?
As with many things in life, moderation is key. Exercising too much can overexert the body and cause complications. A stress fracture is one painful injury that could develop gradually without you realising till it’s too late.
What are stress fractures?
Stress fractures are tiny cracks on the bone that are caused by accumulated damage to the bone when there is repeated impact on the same area. These fractures develop when muscles become fatigued and cannot absorb the added shock from overexertion. The pain felt from stress fractures is distinct from other conditions in that it intensifies during the workout and dissipates during rest.
Types of stress fractures
Metatarsal stress fracture
Metatarsal bones are the long bones in the foot that link the ankle to the toes. There is usually pain or swelling towards the front or middle of the foot. Like hip stress fractures, such fractures are common when runners intensify their training. Do note that those with osteoporosis or inflamed joints are at greater risk of metatarsal stress fractures.
Metatarsal stress fractures are more common in gymnasts, ballet dancers and hikers as their activities place continual stress on the feet.
Navicular stress fracture
The navicular is one of the tarsal bones in the ankle, sitting above the heel bone, on top of the middle of the foot.
You may experience pain across the inside arch of the foot or a vague mid-foot ache just past the ankle joint. Navicular stress fractures are common because compressive forces are focused on this bone when the foot hits the ground. The low blood supply in this region makes the healing of minor injuries more difficult, thus injuries are more likely to develop into a stress fracture.
Navicular stress fractures are more common in high-impact sports such as sprinting, jumping, hurdling, basketball and soccer.
Tibia stress fracture
There are 2 shin bones in each lower leg and the larger of the two is the tibia bone. As a weight bearing bone, the tibia cracks when muscles are unable to absorb the stress and hence rely on the bone. Stress is often created by repeated pounding of the foot on hard surfaces. Patients generally experience pain at the shin bone which increases with activity and decreases with rest.
Tibia stress fractures are more common in volleyball players, runners and gymnasts.
Rib stress fracture
There are 12 ribs each on the left and right, and the first rib is the most susceptible to injury. This is because the first rib is weaker and thinner due to grooves for blood vessels to travel. Patients are likely to notice pain on the side of their neck, upper back or back of the shoulder. The pain may be exacerbated by deep breathing, coughing or moving the arm over the head.
Rib stress fractures are more common in sports that involve vigorous shoulder motions, such as rowing, baseball, dance and windsurfing.
Hip stress fracture
A hip stress fracture is a serious injury to the ball of the hip joint. Patients typically experience aching groin pain. This pain may worsen when lying down or when the foot hits the ground when running or hopping. Hip stress fractures that are displaced (misaligned bones) may lead to serious complications like hip osteonecrosis, a condition where blood supply to the hip bone is affected.
Hip stress fractures are more common in long-distance runners, military recruits and mid-impact sports athletes.
How to prevent stress fractures
Other than cross-training to ensure that stress is evenly distributed across different muscles, it is also important to include calcium-rich foods to support bone growth. Also, shoes lose their cushioning and support over time and hence, athletes should replace old sport shoes. As a guide, after clocking 500 kilometres with one pair of shoes, consider replacing it with a new pair.
Finally, progress slowly in any sport. This means to gradually increase the duration and intensity of your workouts to manage stress placed on your body.
How to treat stress fractures
If you think you might be suffering from a stress fracture, stop exercising immediately and consult a doctor. While x-ray scans may not be conclusive, bone scans or magnetic resonance imaging (MRI) are effective in identifying the condition.
The common prescription is rest, anti-inflammatory medication, stretching and muscle strengthening. Resting is mandatory and the injury may take 6 – 12 weeks to heal, depending on its severity. (If you really have to stay fit for your next marathon or competition, limit yourself to low-impact workouts or engage in light cross-training.)
Stress fractures may take a much longer time to heal than normal fractures because they occur due to repeated, accumulated stress over time. Sometimes, they fail to heal and require surgery for fixation and bone grafting. In some cases, casts or hard-soled shoes may be advised by doctors.
Article reviewed by Dr Tan Ken Jin, orthopaedic surgeon at Mount Elizabeth Novena Hospital.