Medicines for Bone cyst

What it is

A bone cyst is a fluid-filled cavity (space) that develops within a bone. Most bone cysts are benign (non-cancerous) and harmless, and they are most common in children and teenagers, though they can occur in adults. There are different types, the most common being a "simple" or "unicameral" bone cyst, and another type called an aneurysmal bone cyst; these differ in their features but are both benign. Bone cysts often cause no symptoms and are frequently discovered by chance — for example on an X-ray taken for another reason (such as after an injury). When they do cause symptoms, these can include: a dull ache or pain in the affected area; swelling; or, importantly, a fracture (break) of the bone through the weakened area, sometimes after only a minor injury, because a cyst can make that part of the bone weaker — in fact, a bone cyst is sometimes first discovered when such a fracture occurs. Bone cysts most often occur in the long bones (such as the upper arm or thigh bone), but can occur elsewhere. Because bone cysts are usually benign, and because many cause no problems, the approach depends on the type, size, location, and whether the cyst is causing symptoms or weakening the bone: many are simply monitored (observed), as some, particularly simple bone cysts in children, can resolve or heal on their own over time (including after a fracture heals); while cysts that are causing problems, are large, are significantly weakening the bone, or are at risk of fracture may be treated. It is important, when a cyst-like lesion is found in a bone, that it is assessed to confirm it is a benign cyst and not something else, as some bone lesions need different management. The key messages are that most bone cysts are benign and harmless, often found by chance and mainly in children and young people, that many need only monitoring (and some heal on their own), and that treatment is used when a cyst weakens the bone or causes problems.

How it is treated

Bone cysts are assessed to confirm they are benign, and are then managed according to the type, size, location, and whether they cause symptoms or weaken the bone — often by monitoring, with treatment where needed. When a cyst-like lesion is found in a bone (often incidentally, or after a fracture), it is important to assess it to confirm the diagnosis — this involves imaging (such as X-rays, and sometimes MRI or other scans), and occasionally a biopsy, to confirm it is a benign bone cyst and to determine the type, and to distinguish it from other bone conditions that would need different management. Once confirmed as a benign cyst, management depends on the situation: many bone cysts, particularly simple bone cysts in children that are not causing significant problems, are simply monitored with periodic imaging, as they may remain stable, shrink, or heal on their own over time (including as a child grows, and sometimes after a fracture through the cyst heals). Treatment is considered when a cyst is causing symptoms, is large, is significantly weakening the bone or putting it at risk of fracture, or in certain locations. Treatment options, decided by specialists (such as orthopaedic surgeons), can include: procedures to treat the cyst — for example injections into the cyst (such as steroid or other substances) to help it heal, or procedures to drain and treat it; and, in some cases, surgery to remove or curette (scrape out) the cyst and, if needed, fill or graft the space and strengthen the bone. If a fracture has occurred through a cyst, the fracture is treated (and sometimes the fracture healing helps the cyst resolve). Aneurysmal bone cysts and certain other cysts may need more active treatment. Follow-up is arranged to monitor the cyst and check for any recurrence, as some cysts can recur after treatment. The overall aims are to confirm the cyst is benign, prevent or treat any fracture or bone weakness, and preserve the bone and function. The reassuring messages are that most bone cysts are benign and harmless, that many (especially simple cysts in children) need only monitoring and can heal on their own, and that effective treatments are available when a cyst weakens the bone or causes problems — while it is important that a bone lesion is assessed to confirm it is a benign cyst.