An Approach to Arthritis

		Definition
	l Disease that affects bones on both sides of the joint space and l Narrows the space in between them

		Arthritis or Not
Classification l Hypertrophic n Hallmarks l Bone production l Sclerosis l Infectious n Hallmark l Destruction of articular cortex l Erosive n Hallmark l Erosions			DJD				AVN

Hypertrophic Arthritis
		l  Degenerative arthritis n Primary n Secondary l  Charcot arthropathy

1º Degenerative Arthritis
		l Intrinsic degeneration of articular cartilage l Excessive wear and tear n Most commonly hips and knees n Less commonly shoulders and elbows

1º Degenerative Arthritis
		l X-ray Findings n Narrowing of  joint space n Subchondral sclerosis n Marginal osteophyte formation n Subchondral cysts

	1º DJD of knees affects medial, weight-bearing surface		1º DJD of hips affects superior, weight-bearing surface

	1º Degenerative Arthritis Hands
		l Not due to mechanical stress l F:M  10:1 l Most often involves DIP joints n Sclerosis n Marginal osteophyte formation l 1st MCP joint of thumb

		1º DJD of Hands

	2º Degenerative Arthritis
		l Another process destroys articular cartilage l Degenerative changes supervene l How to recognize n Atypical locations (CPPD and knee) n Atypical appearance (Marked DJD of 1 hip) n Atypical age (DJD in 20 year-old

	2º Degenerative Arthritis Causes
		l Trauma l Infection l Avascular necrosis l CPPD l RA l Hemophilia

	2º Degenerative Arthritis More Causes
		l Hemochromatosis l Acromegaly l Ochronosis l Wilson's Disease l Bottom line: Any arthritis can end as DJD

	2º DJD of right ankle following fracture

	Calcium Pyrophosphate Deposition Disease (CPPD) n May be idiopathic or associated with l Hyperparathyroidism, hemochromatosis n Symmetric involvement: knees (most common), wrists, MCPs n Sudden onset of pain and fever n Clinically l Tender, swollen, red, LOM
CPPD Findings n Calcification of articular cartilage l Knee, hip, shoulder l Triangular fibrocartilage of ulna l Symphysis n Large subchondral cysts n Preferential involvement of femero- patellar compartment

	Chondrocalcinosis

	Hypertrophic Arthritis Classification
		l  Degenerative arthritis n Primary n Secondary l  Charcot arthropathy

		Charcot’s Arthropathy General
	l Disturbance in sensation leads to multiple microfractures l Pain sensation intact from muscles and soft tissue l Causes n Shoulders – syrinx, spinal tumor n Hips – tertiary syphilis, diabetes n Feet – diabetes

	Charcot’s Arthropathy Findings
		l X-ray findings n Fragmentation n Soft tissue swelling n Destruction of joint n Sclerosis n Osteophytosis

	Charcot’s Knees-Diabetes

	Charcot’s Shoulder - Syrinx

	Charcot’s Arthropathy of Foot - Diabetes

	Charcot’s Shoulder - Syrinx

		Classification
	l Hypertrophic n Hallmarks l Bone production l Sclerosis l Infectious n Hallmark l Destruction of articular cortex l Erosive n Hallmark l Erosions

		Infectious Arthritis
	l More common in adults n Usually from local trauma-surgery or accident n Children get osteomyelitis l Destruction of articular cartilage & cortex l Tends to affect one joint (DDx from gout) n Fingers from human bites n Feet from diabetes n Hips from THRs

		Normal joint			Normal articular cortex

		Infectious Arthritis Causes
	l Usually staph - “early” destruction of articular cortex n Rapid course (unlike most arthritides) l TB spreads via bloodstream from lung n More protracted course n In children, spine most common; in adults, knee n Severe osteoporosis l Healing with ankylosis common in both

						Acetabular white line
		Septic arthritis of hip with pathologic fracture					Normal hip

		Septic arthritis of toe

		TB septic arthritis over 1 year

		Classification Erosive Arthritis
	l Hypertrophic n Hallmarks l Bone production l Sclerosis l Infectious n Hallmark l Destruction of articular cortex l Erosive n Hallmark l Erosions

		Erosive Arthritis General
	l Synovial proliferation (pannus formation) l Inflammation l Erosions seen in small joints (hands) better than large (hips) n Destroy portion of cortex

	Erosive Arthritis Types
		l Rheumatoid arthritis l Gout l Hemophilia l Erosive osteoarthritis l Rheumatoid variants n Psoriatic arthritis n Reiter's n Ankylosing spondylitis n Inflammatory bowel disease

		Erosive Arthritis More Types
	n Connective tissue disease l Scleroderma l SLE l Jaccoud's arthropathy l Sarcoidosis n  Rare l Amyloid

		Rheumatoid Arthritis General
	l Bilaterally symmetrical n Earliest change: STS MCP, PIP, ulnar styloid l Radiocarpal jt most commonly narrowed l Periarticular demineralization l Begins MCP jts of 1st and 2nd fingers l Large joints usually no erosions

		Rheumatoid Arthritis General
	l Can lead to 2º DJD n Marked narrowing of joint space with intact articular cortex, think of RA l Little or no sclerosis l Especially, hips and knees

	RA Hands
	RA of Hips – Marked narrowing, little sclerosis

			RA usually involves 5th MT-P joint first
	RA of Foot
Gout General l Long latent period between onset of symptoms and bone changes l Asymmetric and monoarticular l More common in males l Most common at 1st MT-P joint l Tophi rarely calcify l Olecranon bursitis is common

		Gout Findings
	l Juxta-articular erosions n Sharply marginated with sclerotic rims n Overhanging edges (rat-bites) l No joint space narrowing until later l Little or no osteoporosis l Soft tissue swelling l Tophi not calcified