Stress fractures: causes, symptoms and recovery

Bone is living tissue that is constantly renewed. A Sussex NHS leaflet explains that if a bone is overworked, renewal may not keep pace with the stress it is under, and a crack can develop. The crack is often tiny, and several can form over time.

BOFAS, the British Orthopaedic Foot and Ankle Society, defines stress fractures as the result of microscopic injuries from repeated submaximal trauma. Sometimes the bone only becomes inflamed, with swelling, heat and pain, but it can progress to a full break.

Gloucestershire Hospitals notes that the foot is the most common site seen in its emergency department.

The common thread is load that is greater than the bone is used to. The Sussex leaflet lists doing an activity that is new or unusual for you, increasing an activity rapidly, changing footwear, or returning to your usual activity after a long period of doing much less.

Gloucestershire Hospitals adds people who take part in high-impact sports, those who walk long distances on uneven surfaces, and menopausal women, whose bones are often weaker. Some stress fractures develop from normal use of bone weakened by conditions such as osteoporosis.

BOFAS lists running, jumping, marching, acrobatics and dancing as repetitive stressful activities, and describes a "female athlete triad" of missed periods, low bone mineral density and dietary restraint that raises risk. The Sussex leaflet also names eating disorders, low bone density and problems absorbing vitamins and minerals.

The Sussex leaflet describes a dull pain in the foot that tends to increase with activity or weight-bearing and settle with rest, plus some swelling. Pain is worse when you press directly on the affected bone. Gloucestershire Hospitals says it tends to hurt in very specific areas and gets worse with impact such as running or jumping.

Different bones behave differently. BOFAS notes that the second and third metatarsals usually heal well, while fractures at the base of the second metatarsal are more prone to not healing. The fifth metatarsal can cause chronic pain along the outer foot. The navicular, a bone in the midfoot, causes activity-related pain on top of the foot and is often missed on X-ray.

The Sussex leaflet says a clinician can usually tell from your story and examination. Some people are diagnosed without an X-ray. An X-ray may be used to look for a clear break, but not all stress fractures appear, and one taken weeks later can show changes missed at first. A repeat is only needed if it would change management or the fracture may be unstable.

When the diagnosis is uncertain or the bone is a higher-risk site, BOFAS says ultrasound, MRI or, for the navicular, CT may be considered if they will affect management. Many hospitals handle foot injuries through a virtual fracture clinic, where the team reviews the case and advises by phone or message.

Most foot stress fractures are treated without surgery. Gloucestershire Hospitals advises stopping the activity that caused the pain, using ice and elevation, and wearing protective footwear such as a stiff-soled shoe, wooden-soled sandal or removable boot. Sometimes a cast or splint is used for unstable bones, usually removed after 4 to 6 weeks.

A Bedfordshire Hospitals leaflet describes wearing the boot for walking for 6 weeks, doing simple foot and ankle movements several times a day from the start, weaning out of the boot by about 8 weeks, and avoiding impact activity such as running and jumping for 3 months. Pain and swelling can last 3 to 6 months.

Smoking slows healing, according to the Sussex and Bedfordshire leaflets, and both advise stopping or cutting down. Surgery is considered by BOFAS mainly for proximal fractures or painful non-union.

The Sussex leaflet suggests that, if pain-free, people can return slowly to lower-impact sport after 6 weeks, changing only one thing at a time such as time, speed or power, and increasing by about 10% each session. It suggests swimming, cycling or walking on even ground while recovering.

It warns against pushing through pain or returning too soon. If pain returns, reduce activity and let it settle. Work that keeps you on your feet may need light duties at first. Driving is possible once you are out of the boot, can walk comfortably and can perform an emergency stop without pain.

Most foot stress fractures are handled through an urgent treatment centre, A&E or a virtual fracture clinic, then followed by self-care. Review is usually offered only if pain and swelling persist beyond about 3 months, as the Bedfordshire leaflet says.

A private foot and ankle orthopaedic specialist or sports physiotherapist can help if the diagnosis is unclear, the pain is not settling, or the site is one prone to non-healing. They can also look at footwear, training load, bone health and vitamin D.