Bone Lesions

quickster2008's version from 2016-11-12 21:15

General Principles

Question Answer
Differential Diagnosis for benign cystic bone lesionFibrous dysplasia, Enchondroma, Eosinophilic Granuloma, Giant Cell Tumor, Non-ossifying Fibroma, Osteoblastoma, Metastatic disease, Myeloma, Aneurysmal Bone Cyst, Solitary Bone Cyst, Hyperparathyroidism, Infection, Chondroblastoma, Chondromyxoid
Which diagnosis should always be mentioned in your differential?Infection
Define CherubismTerm given to appearance of child's face who has fibrous dysplasia of the jaw. This comes from the physical appearance of a child with puffed out cheeks having an angelic look
Multiple Enchondromas are found in what disease entities?Ollier disease and Maffucci sydnrome
Define Maffucci SyndromeSyndrome associated with multiple enchondromas with associated phleboliths generally found in the hands
Fibrous dysplasia located in multiple bones can be associated with what syndromeMcCune-Albright
Must include this entity in your differential with bone lesion in tibia representing possible fibrous dysplasiaAdamantinoma, a malignant lesion
The finding of Periostitis excludes which diagnosesFibrous Dysplasia, Enchondroma, Non-ossifying Fibroma, and Solitary Bone Cyst


Question Answer
OsteochondromaPenduculated, cauliflower shaped benign tumor arising from cartilage and bone. Outgrowth of bone. Not included in FEGNOMASHIC mneumonic
ChondroblastomaRare benign bony lesion located in the epiphysis
OsteoblastomaVery rare benign bone tumor seen most often in the posterior elements of the spine DDx: ABC, TB
Chondromyxoid FibromaExtremely rare benign bone tumor that resembles NOF but can occur at any age
Parosteal ChondromaBony lesion immediately adjacent to periosteum which often causes a saucer-like erosion of the underlying cortex. Seen mostly in the phalanges of the hands but can also be seen at the ends of long bones or rarely in the carpal bones
EnchondromaBenign cartilaginous tumor found most commonly in the phalanges of the hand. If outside the hand, it will contain calcified chondroid matrix
Non-Ossifying FibromaMost common bony lesion in patients less than 30 years old which is generally located in the metaphysis.Typically has thin, sclerotic, slightly expansile boder with periosteal scalloping
Fibrous DysplasiaBenign bony lesion found in all age groups that has a highly variable appearance, but generally has both sclerotic and lytic features. Located mostly in ribs, pelvis, proximal femur, and skull
Eosinophilic GranulomaBenign bony lesion found in patient under the age of 30 that can look like any other bony lesion and therefore must be included in your differential for any patient under the age of 30. This is the only benign tumor that can have a bony seqestrum, which is seen only in EG, Lymphoma, Fibrosarcoma, and osteomyelitis. Osteoid osteoma may mimic bony sequestrum if nidus is calcified
Giant Cell TumorBenign bone tumor which is seen almost exclusively in adults and is characterized by location in the epiphyses, abuttment of joint, and sharply defined non-sclerotic border
Aneurysmal Bone CystBenign bony lesion occurring in patients less than 30 yrs old which is characteristically expansile and can be found anywhere. Consider if lesion in posterior element of spine similar to Osteoblastoma. Can be painful
Simple Bone CystCharacteristically centrally located and are seen in patients less than 30 years old. Look for associated fractures and "fallen fragment sign"
Brown TumorAssociated with hyperparathyroidism. Must have presence of subperiosteal bone resorption for this diagnosis to be considered
OsteosarcomaMost common bone neoplasm below the age 30; Can be located just about anywhere, although has a tendency for the end of long bones; Appear destructive with obvious sclerosis (rarely they are entirely lytic); Heterogenous signal on MRI
Parosteal OsteosarcomaOsteosarcoma arising from periosteum and grows outside the bone. Look for cortical invasion. Do not confuse with cortical desmoid or myositis ossificans
Ewing SarcomaClasically a permeative lesion in a long bone of a child; look for onion skin periostitis, but this is not always present

Clues to Diagnoses

Question Answer
Lytic lesion with non-sclerotic border at end of long bone that touches joint in an adultGiant Cell Tumor