Pathophysiology Chapter 52

1. CHAPTER 52
ALTERATIONS IN
MUSCULOSKELETAL FUNCTION:
RHEUMATIC DISORDERS

2. LOCAL DISORDERS OF
JOINT FUNCTION
• Arthritis is the most common disabling
musculoskeletal disorder in the United States
• Increasing age is a major factor in many
forms

3. OSTEOARTHRITIS
• A local degenerative joint disorder
associated with aging and wear and tear
from repetitive stress
• Characterized by loss of articular cartilage,
wear of underlying bone, and the formation
of bone spurs; noninflammatory; weight-
bearing joints are often affected

4. OSTEOARTHRITIS (CONT.)
• Signs and symptoms are localized including
joint pain and crepitus with movement
• Treatment aimed at improving function with
physical therapy and reducing pain with
acetaminophen or NSAIDs and intra-articular
injections of corticosteroids or visco-
supplementation

5. OSTEOARTHRITIS (CONT.)

6. INFECTIOUS ARTHRITIS
• Joint infection most often due to bacteria
usually by way of the bloodstream
• Signs and symptoms are due to localized
infection and the systemic manifestation of
inflammation
• Appropriate antibiotic therapy over 4-6
weeks with therapeutic joint aspiration,
arthroscopy or surgical drainage

7. JOINT PROSTHESIS INFECTION
• Staphylococcus epidermidis is a common
agent in prosthetic joint infection
• Generally requires removal of the prosthesis
followed by intravenous antibiotic therapy for
4-6 weeks
• Antibiotic beads may also be placed in the
wound
• Prosthesis may be replaced when wound
cultures show no growth

8. SYSTEMIC DISORDERS OF
JOINT FUNCTION
• May be related to infectious processes, or
have an autoimmune or genetic etiology
• Generally cause systemic signs and symptoms
involving multiple joints and other connective
tissue structures
• Joint destruction is inflammatory and involves
synovial membranes, cartilage, joint capsule,
and surrounding ligaments and tendons

9. RHEUMATOID ARTHRITIS
• Possibly related to autoimmune abnormality
in genetically predisposed individuals
• American Rheumatism Association criteria
used for diagnosis
• DMARDs recommended early in the disease
• Treatment may include NSAIDs,
corticosteroids, and biological agents

10. RHEUMATOID ARTHRITIS
(CONT.)

11. SYSTEMIC LUPUS
ERYTHEMATOSUS
• Chronic multisystem, inflammatory,
autoimmune disease characterized by
periods of exacerbations and remission with
multiple organs affected
• Results from B-lymphocytic overactivity
• Most common features are arthralgias and
synovitis
• Treatment includes topical corticosteroids,
avoidance of sun, NSAIDs and/or antimalarial
drugs, and immunosuppressive agents

12. SCLERODERMA
• Multisystem inflammatory connective tissue
disease characterized by skin thickening and
deposition of collagenous tissue resulting in
severe fibrosis
• Clinical manifestations may include Raynaud
phenomenon, polyarthritis, sclerodactyly,
macular rash, and internal organ involvement
• Organ specific symptomatic treatments

13. ANKYLOSING SPONDYLITIS
• Arthritis of the sacroiliac joints that involves
the axial skeleton, and sometimes the
peripheral joints
• Clinical features may include low back pain,
severe morning stiffness, and limited range of
motion
• Treatment includes NSAIDs, DMARDs, agents
that inhibit TNF-alpha

14. POLYMYOSITIS AND
DERMATOMYOSITIS
• Idiopathic inflammatory myopathies; focal or
extensive degeneration of muscle fibers due
to inflammatory infiltrates of lymphocytes and
macrophages
• Weakness in the proximal limb muscles,
abnormal electromyography and skeletal
muscle biopsy; skin and cardiac involvement
common
• Treatment: corticosteroids,
immunosuppressive agents, and physical
therapy

15. POSTINFECTIOUS SYSTEMIC
DISORDERS
• Reactive arthritis (previously named Reiter
syndrome) preceded by urethritis, cervicitis, or
dysentery
• May occur in those genetically susceptible
following a bacterial infection
• Oligoarthritis typically appears 2-6 weeks after
infectious episode
• Treatment may include NSAIDs, intra-articular
corticosteroids and/or immune-regulating
agents

16. ACUTE RHEUMATIC FEVER
• Inflammatory disease that follows a beta-
hemolytic group A streptococcal pharyngeal
infection
• Onset typically 2-6 weeks after infection
• Peak incidence is between 5 and 15 years
• Presents with polyarthritis and carditis
• Aspirin, NSAIDs, corticosteroids, and
antibiotics used for treatment

17. POSTPARASITIC DISORDERS
• Lyme disease
• Caused by Borrelia burgdorferi, a tick-borne
spirochete; carried by deer tick
• Tick bite produces red macule or papule
accompanied by flulike symptoms and may
develop other organ involvement
• Treatment: oral or parenteral antibiotics

18. JOINT DYSFUNCTION
SECONDARY
TO OTHER DISEASES
• Neurovascular, hematologic, and metabolic
disorders may lead to associated disorders of
joint function
• Most related to chronic diseases, such as
diabetes, or hemophilia, or due to altered
metabolic processes such as uric acid
production and clearance

19. PSORIATIC ARTHRITIS
• Inflammatory arthritis associated with
psoriasis; peak age of onset 30-55 years
• Genetic factors are supported
• Peripheral joint involvement with asymmetric
oligoarthritis; combination of soft-tissue and
peripheral joint disease
• Treatment may include NSAIDs and
corticosteroids or immunosuppressive therapy

20. ENTEROPATHIC ARTHRITIS
• Articular manifestations of two inflammatory
bowel diseases; ulcerative colitis and Crohn
disease
• Peripheral arthritis, spondylitis, and
involvement of muscle and bone
• May include ocular manifestations
• Treatment may include NSAIDs, COX-2
inhibitors, corticosteroids, or TNF-alpha
antagonists

21. NEUROPATHIC
OSTEOARTHROPATHY
• Commonly called Charcot joint
• Bone and joint abnormalities due to loss in
normal position sense and pain responses
• Most commonly due to diabetes, tabes
dorsalis, and syringomyelia
• Management requires protection of involved
joint through immobilization and less weight
bearing

22. HEMOPHILIC ARTHROPATHY
• Hemorrhage stimulates a synovial proliferative
response, chronic inflammation with release
of degradative proteinase, and changes in
cartilage composition with less resistance to
stress
• Larger joints affected more commonly
• Medical treatment to enhance clotting is
imperative as well as education and
prevention of joint deformity

23. GOUT
• Heterogeneous disorder in which disturbance
of uric acid metabolism leads to deposition of
monosodium urate salts in articular,
periarticular, and subcutaneous tissue; risk
increases with age
• Recurrent attacks of articular and
periarticular inflammation, accumulation of
tophi, renal impairment, and uric acid calculi

24. ASYMPTOMATIC
HYPERURICEMIA
• No clinical signs; however, serum urate levels
are elevated
• In males, can begin at puberty
• In females, usually does not appear before
menopause
• No treatment required at this stage

25. ACUTE GOUTY ARTHRITIS
• Most common early clinical sign
• Weight-bearing joints most commonly
affected; warm, red, and tender to palpation
• MTP joint of the great toe most often involved
• Initial attacks can last 1-14 days; later attacks
tend to become more frequent

26. GOUT

27. INTERCRITICAL GOUT
• Intercritical gout is used to describe the
intervals between acute attacks
• No symptoms present but urate crystals can
still be aspirated from involved joints

28. CHRONIC TOPHACEOUS GOUT
• Advanced stage of gout
• Tophi begin to appear about 10 years after
initial onset of gout; appear commonly in the
synovium, subchondral bone, olecranon
bursa, and infrapatellar and Achilles tendons
• Tophi can affect tissues of the ears and eyes,
and cardiac and renal structures
• Deforming arthritis can develop

29. GOUT
• Treatment: an acute gouty attack usually
requires NSAIDs, corticosteroids, and
colchicine
• Colchicine may be used at a lower dose to
prevent recurrent attacks
• Medications to correct hyperuricemia and
prevent gout flares may target uric acid
secretion by the kidneys or uric acid
production (allopurinol)

30. ADULT-ONSET STILL DISEASE
• Form of seronegative polyarthritis with a
number of symptoms similar to JRA
• High-spiking fever, rash on trunk and
extremities, and possibly sore throat; can
involve PIP and MCP joints of the hands and
include visceral involvement
• Some respond well to high-dose aspirin or
NSAIDs; corticosteroids may be used

31. PEDIATRIC JOINT DISORDERS
• Nonarticular rheumatism: common soft tissue
syndrome with nocturnal pain; also known as
‘growing pains’
• Hypermobility of joints: may cause pain in
joints
• Juvenile idiopathic arthritis (juvenile
rheumatoid arthritis [JRA]): chronic
inflammatory disease affecting the synovium

32. JUVENILE IDIOPATHIC
ARTHRITIS
• Three subtypes
• Systemic onset with rash, high fever, fatigue,
lymphadenopathy, splenomegaly, and polyarthritis
• Polyarticular arthritis localized to 5 or more joints
• Pauciarticular arthritis affecting 4 or fewer joints
• Treatment: NSAIDs, corticosteroids, DMARDs,
biologic-disease modifying agents, PT/OT