00:00 / 00:00
Lordosis, kyphosis, and scoliosis
Osteomalacia and rickets
Paget disease of bone
Calcium pyrophosphate deposition disease (pseudogout)
Juvenile idiopathic arthritis
Inclusion body myopathy
Degenerative disc disease
Spinal disc herniation
Achilles tendon rupture
Anterior cruciate ligament injury
Iliotibial band syndrome
Patellar tendon rupture
Patellofemoral pain syndrome
Carpal tunnel syndrome
Thoracic outlet syndrome
Radial head subluxation (Nursemaid elbow)
Rotator cuff tear
Lambert-Eaton myasthenic syndrome
Limited systemic sclerosis (CREST syndrome)
Mixed connective tissue disease
Systemic lupus erythematosus
Developmental dysplasia of the hip
Osgood-Schlatter disease (traction apophysitis)
Slipped capital femoral epiphysis
Back pain: Pathology review
Bone disorders: Pathology review
Bone tumors: Pathology review
Gout and pseudogout: Pathology review
Muscular dystrophies and mitochondrial myopathies: Pathology review
Myalgias and myositis: Pathology review
Neuromuscular junction disorders: Pathology review
Pediatric musculoskeletal disorders: Pathology review
Rheumatoid arthritis and osteoarthritis: Pathology review
Scleroderma: Pathology review
Seronegative and septic arthritis: Pathology review
Sjogren syndrome: Pathology review
Systemic lupus erythematosus (SLE): Pathology review
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Living with Psoriasis and Psoriatic Arthritis
psoriatic arthritis p. 475
HLA-B25 and p. 98
leflunomide for p. 495
psoriasis and p. 485
In psoriatic arthritis, arthritis means joint inflammation, and psoriatic refers to psoriasis, which is an autoimmune disease characterized by red scaly patches in the skin.
So psoriatic arthritis is a type of joint inflammation that happens in individuals with psoriasis.
Psoriatic arthritis is also one disease in a group of diseases called seronegative spondyloarthropathies.
Spondyloarthropathies are autoimmune diseases that affect the joints, and they’re seronegative, meaning that there aren’t any specific autoantibodies linked to them.
Normally, immune cells are ready to spot and destroy anything foreign that could cause the body harm.
To help with this, most cells express the gene HLA-B27, which encodes a protein that forms a major histocompatibility complex, or MHC, class I molecule that sits on the surface of the cell membrane.
This MHC class I molecule acts like a serving platter, presenting molecules from within the cell for the immune system to sample.
A CD8+ T-cell, also called a cytotoxic T-cell, uses its T-cell receptor to bind to the antigen presented by the MHC class I molecule.
Normally, the antigen that’s presented is from the cell, and the immune system recognizes it as a harmless self-antigen, which leads to no response.
Now, many individuals with psoriatic arthritis have a specific version of the gene HLA-B27, which somehow leads to an autoimmune process.
In these individuals, the immune system attacks self-antigens specifically ones in the joints.
Exactly what causes this is unclear, but it's clear that the gene is not enough to trigger psoriatic arthritis.
Psoriatic arthritis is a type of inflammatory arthritis that will develop in some people with the chronic skin condition psoriasis. Psoriatic arthritis typically affects the joints of the fingers and toes, as well as the spine, hips, and knees, causing joint pain, swelling, and stiffness. Treatment includes NSAIDs, sulfasalazine, and methotrexate.
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