Bone disease Flashcards
Most common types of bone tumour
Metastatic: Breast, bronchus, Thyroid, Kidney, prostate
Haematopoietic: Lymphoma, leukaemia, myeloma
Presenting complaints for bone tumours
Incidental finding
Pathological fracture
Bony pain (Esp night pain)
Soft tissue swelling
Painless bony mass
Characteristic location of chondrosarcoma
Pelvis
Characteristic location of osteoblastoma
Posterior spine
Characteristic location of simple bone cyst
Proximal humerus
Characteristic location of adamantinoma
Tibia diaphysis
Tumours in patients <20
Osteosarcoma
Osteoid osteoma
Ewing’s
Simple cyst
Chondroblastoma
Tumours in patients >60
Mets, myeloma, Chondrosarcoma, malignant fibrous histiocytoma
Tumours in middle-aged patients (20-60)
Giant cell
Malignant fibrous histiocytoma
Lymphoma
Chondrosarcoma
Mets
Features of bone tumours to look for on X-ray
Periosteal reaction
Zone of transition
Cortical breach
Bone loss
Types of periosteal reaction to tumour
None
Solid
Lamellated
Spiculated/sunburst
Codman’s triangle
Radiology of zone of transition
Most reliable indicator of benign vs malignant
Can be narrow or wide
Patterns of bone destruction
Geographic
Moth-eaten
Permeative
Presentation of osteoid osteoma
Small solitary nodule
Cortical
Central nidus, lytic surroundings + sclerotic rim
Painful (night pain) but responds to NSAIDs
5-25y, M:F 3:1
Management of osteoid osteoma
Radioablation
Surgical excision
NSAIDs
Presentation of osteochondroma
90% isolated lesion due to abnormal growth of growth plate
Growth ceases with growth plate fusion
Painless lumps or pain from soft tissue impingement
Points away from affected joint w/ continuous cortex
Management of osteochondroma
Excise if large/suspicious
Small risk of malignant transformation (higher in hereditary multiple exostoses)
What is an enchondroma?
Intramedullary cartilage-forming lesion
Cortical thinning
no periosteal reaction
lytic/mottled appearance
Management of enchondroma
None necessary unless painful/enlarging
Small risk of malignant change (higher in Ollier’s or Marfucci’s)
Aggressive vs non-aggressive lesions
Presentation of chondroblastoma
Benign tumour
Epiphyseal, lower limb/prox humerus
Young patients (10-25)
Round, lytic, well-defined X-RAY lesion
Presentation of fibrous cortical defect/non-ossifying fibroma
Young children
Arises from cortex –> thing sclerotic rim + oval-shaped lucent lesion
Distal femur/tibia
Benign, asymptomatic
Fibrous dysplasia
Developmental abnormality, becomes evident in adolescence
Ribs, femur, prox tibia esp affected (shepherd’s crook appearance)
Multiple fractures, heal but remain deformed
Treat by strengthening + straightening bone
Intramedullary bulged cortex
Simple bone cyst
Well-defined circular lucent lesion in centre (c.f. aneurysmal expansile + blood-filled)
Mainly in children (c.f. aneurysmal in teenagers)
Giant cell tumours
Late teens, 3rd and 4th decades, F>M
Lytic lesions, mainly around knees
Metaphyseal
Sharp zone of transition
Benign
Ewing’s sarcoma presentation
Young child
Most commonly in femur/tibia diaphysis
Pain/swelling of weeks-months + systemic upset
Periosteal reaction + lytic + destructive (radiolucent) lesion
Endocrine causes of osteoporosis
Post-menopausal oestrogen deficiency (late menarche/early menopause)
Hyperparathyroidism, hyperthyroidism
Cushing’s, hypogonadism
Corticosteroid excess
Investigations for osteoporosis
DEXA scan (<-2.5 is bad, <-1 osteopaenia)
TFTs, U&Es, LFTs
Bone profile (Ca, PTH)
Consider cortisol, testosterone, oestradiol, VitD
Multiple myeloma screen (ESR, serum IG + electrophoresis, urinary bence-jones)
Treatment for osteoporosis
Ca and VitD
Bisphosphonate
Synthetic PTH (teriparatide)
Denozumab (RANK-L biologic)
HRT
Exercise, weight loss
Stop smoking
Clinical features of osteomalacia
VitD deficiency
Bone pain/waddling gait
Polyarthralgia
Pathological fractures
Subperiosteal erosions/cortical compression fractures in Looser’s zone
Proximal myopathy w/ normal CK
Clinical features of Paget’s
Bone tenderness
cortical thickening, sclerosis
Deafness from nerve compression
Headache
Pathological fractures
Osteoarthritis
Rarely: osteosarcoma, vascular steal
Often asymptomatic raised ALP
>50-80
Sites commonly affected in Paget’s disease
Pelvis, spine, skull
Genetics of Ewing sarcoma
Mutations chromosome 11 and 22
Neuro-ectodermal cell origin
Syndromic associations of enchondromas
Ollier
Marfucci
Locations of primaries in bone mets
Paired midline organs
Lung
Kidney
Thyroid
Prostate
Breast
Radiographic features of malignant tumours
Codman’s triangle
Fuzzy zone of transition
Onion peel appearance
Sunburst
What is an involucrum?
Complication of osteomyelitis
Thick periosteal sheath (new, ossified bone) surrounding sequestrum
What is a sequestrum?
Necrosed bone separated from surrounding bone
Complication of osteomyelitis
What are bisphosphonates?
E.g. alendronate
Bone protection with steroids, and in post-menopausal osteoporotic women
MRI finding osteomyelitis
Loss of high T1 signal in bone marrow
Management of osteomyelitis
Wound swab
Blood cultures
Bone biopsy
IV abx
Surgical debridement
Complications of osteomyelitis
Bone destruction
Pathological fracture
Septic arthritis
Deformity/growth disturbance
Sepsis
Most common XR abnormality in myeloma
Vertebral osteoporosis/osteopaenia
Punched-out Lytic bone lesions may be present
Demographics of osteosarcoma
Most common bone sarcoma
Affects adolescents, mainly males
Paget’s disease in elderly
Clinical features of osteosarcoma
Long bone metaphyses (dital femur > proximal tibia > distal humerus)
Mixed sclerotic/lytic lesion
Codman’s triangle
Presentation of chondrosarcoma
Adults in 5th decade
10% arise from previous enchondroma
Retinoblastoma tumour association
Osteosarcoma
Hereditary multiple exostosis tumours
Osteochondroma
Chondrosarcoma
chromosome 8 and 11 muts
Nutritional causes of osteoporosis
Anorexia nervosa
Malabsorption
VitD deficiency –> hyperPTH
Ca deficiency
Smoking/alcohol/caffeine
Medical (non-endocrine) causes of osteoporosis
RA
Osteogenesis imperfecta
Multiple myeloma
