General MSK

Laurie Lomasney, MDProfessor

Department of Radiology

General MSK

• Disease Categories– Arthropathy– Infection– Congenital– Vascular– Tumor

• Locale– Axial– Appendicular

General MSK by Disease Category

• Disease processes often follow predictable patterns of radiographic change

• Disease processes usually follow particular distribution patterns

• Pretest probability enhances image interpretation and directed reporting

General MSK

• Disease Categories– Arthropathy– Infection– Congenital– Vascular– Tumor

Arthropathy

• Characteristics– Bone density– Erosions– Alignment

• Distribution– Poly vs mono– Symmetric vs asymmetric– Peripheral small vs central large

Arthropathy

Periartic demin

Prox/Symmetric swelling

Wrist/MCP erosions

Palmar/Ulnar deviat

Rheumatoid Arthritis

Arthropathy

Preserved density

Asymmetric swelling

Prox + Distal asymm erosions

Psoriasis

Arthropathy Osteoarthritis

Variable density

No erosions

Eccentric joint narrow

Marginal proliferation

Arthropathy

Preserved density

Debris

Sclerosis

MalalignmentCharcot Arthropathy

General MSK

• Disease Categories– Arthropathy– Infection– Congenital– Vascular– Tumor

Infection

• Characteristics– Periarticular demineralization– Bone erosion– Periosteal new bone– (Adjacent ST defect or Foreign body)

• Distribution– Focal/monostotic vs Multifocal

(uncommon)

Infection

Metaphyseal osteomyelitis

InfectionDIP Pyarthrosis

Hip Pyarthrosis

General MSK

• Disease Categories– Arthropathy– Infection– Congenital– Vascular– Tumor

Congenital

• Variable appearance• Variable consequence

– Incidental– Pathologic

• Always• Sometimes

– Unknown

Congenital

• Ossification neural groove

Congenital

Os Acromiale

CongenitalOs tibiale externum

Congenital

= 80%

Narrow Bony Canal

General MSK

• Disease Categories– Arthropathy– Infection– Congenital– Vascular– Tumor

Vascular (Avascular necrosis)

• Multiple etiologies– Steroid therapy– Collagen vascular disease– Post-traumatic

• Staged appearance– Sclerosis– Collapse– Secondary osteoarthritis

Avascular necrosis

Lunate AVN

Avascular necrosis

Femoral head AVN

General MSK

• Disease Categories– Arthropathy– Infection– Congenital– Vascular– Tumor

Tumor

• Etiologies – Multiple• Distribution – Specific to process

– Axial vs appendicular– Monostotic vs polyostotic– Medullary vs eccentric– Child vs Adult

Tumor

• Characteristics to observe– Well-defined vs permeative– Cortical destruction– Periosteal new bone– Internal matrix– Soft tissue mineralization/mass

TumorNon-ossifying fibroma

Tumor

Giant cell tumor

TumorEnchondroma

Tumor

Chondrosarcoma

TumorOsteogenic sarcoma

Tumor

Osteosarcoma

Gross pathology

General MSK

• Radiology is a four-year residency• Pathology generally follows a

predictable imaging pattern• Knowledge of patterns can

enhance image interpretation

You know you’re in medicine when:• You compliment strangers on the size of

their veins.  • You occasionally have to leave a

patient's room before you start laughing uncontrollably.. 

• You have recurring nightmares about being knocked to the floor and run over by a portable x-ray machine.

Thank you

Laurie Lomasney, MD