Member Login

Simple Bone Cyst (Solitary Bone Cyst, Unicameral Bone Cyst) Print


Simple bone cyst is a sac type fluid filled structure seen in the bone. Simple bone cyst is not a malignant tumor and it shows a benign course. It is seen commonly in proximal humerus and femur. Active bone cysts are adjecent to growth plate. In time, as the child grows the cysts becomes more distal. Simple bone cyst can rarely seen be seen in other bones. Usually it is in only one bone.

What ages is the bone cyst diagnosed?

Simple bone cysts are the most common benign tumors of the bone diagnosed by orthopedic surgeons. It is seen between 5-15 year old children. Bone cysts are not common in adults. Male/female ratio is 2/1.

What causes the simple bone cyst?

Even it is not proven, there are a few theories: The disorders of growth plate or intraosseous venous occlusions theories are the examples.

What are symptoms of bone cysts?

Many bone cysts do not cause any symtoms. They are usually diagnosed incidentally Bone cyst may cause thinning of the bone cortex and in circumstances of weight bearing like standing, walking, patient feel pain in the cyst area. Also, with thinning of the bone cortex, the risk of pathological fracture is increased. In the case of fracture, pain, swelling and functional disability are seen.

How is the diagnosis of the bone cyst made?

The diagnosis is generally made with direct x-rays. If the bone cyst got complicated with the previous treatments and/or fracture or its unusally location, orthopaedic surgeon might request extra studies like MR, Computed Tomography or bone scan.

What is the treatment for simple bone cyst?

While the small cysts are only followed, the large cysts which might have the pathological fracture risk requires treatment. The cyst is penetrated with a special needle and cyst fluid is drawn and inspected. It should be clear and yellowish fluid. A little radio-opaque fluid is injected into the cyst to make sure that it is unicameral and the needle is in the cyst. Then, depending on the orthopedic surgeon's choice either bone marrow obtained from the patient himself or steroid is injected into the cyst.  The larger bone cysts with the risk of pathological fracture os the cyst not responding injection treatment may require surgical treatment. Surgical treatment consists of curettage and grafting and/or internal fixation. When a simple cyst causes pathological fracture, an intra medullary fixation may be included to the surgical treatment.

Key words: simple bone cyst, solitary bone cyst, unicameral bone cyst, orthopedic surgeon, curettage and grafting, steroid injection, pathological fracture.

Comments (0)
Only registered users can write comments!