Type	Incidence (% of all benign bone tumours)	Diagnosis	Pathology features	Treatment	Recurrence rates
Osteochondroma	35	Radiograph, CT and MRI are useful, but biopsy is necessary to confirm diagnosis	Lesions occurring in metaphysis and diametaphysis and projects out of the underlying the bone	Surgery necessary if active or aggressive	<2%
Giant cell tumour	20	Radiograph. CT or MR imaging may be useful	Soft, grey or red tumour often with small blood filled cysts	Necessary due to the risk of malignant transformation	20–50%
Osteoblastoma	14	Conventional radiology. MDCT plays a major role in identifying osseous matrix. CT or MRI may be helpful when there is no mineralisation of the cortex	Aneurysmal bone cyst may superimpose and may be associated with osteoblastoma. In long bones, periosteal reaction may be prominent	1st line: medical followed by controversial radio/chemotherapy or surgical removal	9.8%
Osteoma	12.1	Radiograph, CT and MRI are useful, but biopsy is necessary to confirm diagnosis	Tosseous tissue that comprises of condensed bone with a well-defined border, without surface irregularities or satellite lesions	Surgery necessary if active or aggressive	N/A
Osteoid osteoma	10.8–13.5	Radiograph, CT and MRI are useful, but biopsy is necessary to confirm diagnosis	Intracortical osteoid osteoma produces dense sclerosis around the nidus. Subperiosteal type produces periosteal reaction while spongiosal type produces very little reactive bone.	Surgery necessary if active or aggressive	4.5%
Aneurysmal bone cyst	9.1	Radiograph, CT and MRI are useful, but biopsy is necessary to confirm diagnosis	Blood filled cavernous spaces with septa	Surgery necessary if active or aggressive	31%
Fibrous dysplasia	5–7	Radiograph. CT or MR imaging may be useful	Dense fibrous tissue with osteoid trabeculae	Surgery necessary if chronic bone pain consists after medical treatment, or if complicated by fractures	18%
Enchondroma	2.6	Radiograph, CT and MRI. Histologic evaluation necessary to exclude chondrosarcoma	Masses of hyaline cartilage in lobular formation	Consider if symptomatic or at risk of fracture	0.04%