Bones, Joints, Rheumatology and Skin: What Step 1 Tests

Scope and time budget

Twenty-eight questions is roughly one block and a half. The 18 subtopics split into three families: bone and orthopedics, rheumatology and connective tissue, and dermatology. Plan about one week of study in a 12-week schedule. Anatomy of the limbs is the part that benefits most from drawing, and rheumatology is the part that benefits most from tables of antibodies and drugs.

What is tested

• Bone. Physiology and fracture healing, metabolic bone disease (osteoporosis, osteomalacia, Paget disease), bone tumors and osteomyelitis.
• Joints and rheumatology. Rheumatoid arthritis and seronegative spondyloarthropathies, osteoarthritis, gout and pseudogout, connective tissue diseases (SLE, systemic sclerosis, Sjogren syndrome, dermatomyositis) and the vasculitides.
• Anatomy and injury. Upper and lower limb anatomy and nerve injuries, spine and radiculopathy, joint and sports injuries (ACL, meniscus, rotator cuff).
• Muscle. Muscle physiology and myopathies.
• Pediatric orthopedics. Developmental dysplasia of the hip, slipped capital femoral epiphysis, Legg-Calve-Perthes disease.
• Dermatology. Skin structure, inflammatory dermatoses (psoriasis, eczema, acne), infections and infestations, skin cancers (melanoma, basal cell and squamous cell carcinoma), blistering diseases and cutaneous drug reactions.
• Pharmacology. NSAIDs, glucocorticoids and DMARDs.

Anchor facts and US conventions

These are standard textbook points. Confirm details against your preferred reference.

• Type III hypersensitivity in SLE. SLE is an immune-complex disease, with antinuclear antibodies as the screening test and anti-double-stranded DNA and anti-Smith antibodies as more specific markers. The link to hypersensitivity types is on the blood and immune page.
• Gout versus pseudogout. Gout shows needle-shaped, negatively birefringent urate crystals. Pseudogout shows rhomboid, positively birefringent calcium pyrophosphate crystals.
• Osteomyelitis. Staphylococcus aureus is the most common cause of acute osteomyelitis. Know the exceptions that the stem will signal, such as sickle cell disease and Salmonella.
• Nerve injuries. Learn the classic pairings of injury site and deficit: surgical neck of the humerus and the axillary nerve, midshaft humerus and the radial nerve (wrist drop), medial epicondyle and the ulnar nerve, and the common peroneal nerve at the fibular neck (foot drop).
• Pediatric orthopedics. Slipped capital femoral epiphysis typically presents in an overweight adolescent with hip or knee pain. Legg-Calve-Perthes disease typically presents in a young child with a limp from avascular necrosis of the femoral head.
• Skin cancer. Melanoma prognosis relates to depth of invasion (Breslow thickness). Basal cell carcinoma is the most common skin cancer and rarely metastasizes. Squamous cell carcinoma is linked to ultraviolet exposure and immunosuppression.
• Drugs. NSAIDs inhibit cyclooxygenase and carry GI, renal and cardiovascular risk. Glucocorticoids have a long adverse-effect list (osteoporosis, hyperglycemia, adrenal suppression). DMARD toxicities are favorite questions: methotrexate (bone marrow suppression, hepatotoxicity, with folate as rescue for some effects) is a standard example.

Three typical traps

1. Confusing the arthropathies. Rheumatoid arthritis, osteoarthritis, gout and the spondyloarthropathies differ in joint pattern (symmetric small joints versus asymmetric large joints versus axial), morning stiffness, labs and crystals. The stem usually gives two or three of those clues. Use all of them.
2. Naming the wrong nerve for the finding. Stems describe a functional deficit (cannot abduct the arm, cannot extend the wrist) after an injury. Convert the deficit to the muscle, then the nerve, then the injury site. Do this in order, not in one jump.
3. Calling every rash by the first impression. Skin questions test morphology (papule, plaque, vesicle, bulla), distribution and associated signs. Look at the primary lesion before the history. For blistering diseases, the level of the split and the antibody target distinguish the options.

How to revise this system

• Use images. Pair every skin diagnosis with a picture. Study dermatology with image-based flashcards, then test with image blocks.
• Table the autoantibodies. Antibody, disease, clinical clue. Include SLE, systemic sclerosis, Sjogren syndrome, dermatomyositis and the vasculitides.
• Draw the brachial plexus and the lumbosacral plexus. Label the nerves, the muscles and the injuries.
• Learn the drug toxicities for DMARDs and biologics. They also appear in the immune and multisystem rows, so each hour pays twice.
• Review through the error log. Orthopedics and dermatology are volume topics. Add one line per missed item to a single page, and read that page weekly.

The study plan guide places this system in the middle of the schedule, after the heavier systems.

What the questions look like

Items often include a photograph of a rash, an X-ray description or a short musculoskeletal examination. The final question asks for the diagnosis, the underlying pathology, the nerve injured, the drug to give or the adverse effect of a drug. Our original practice bank follows the same format with conventional units and five options, and it does not copy official or recalled items. For the table of all systems and weights, return to the Step 1 hub, and for the cross-system facts see the high-yield topics guide.

An image habit that pays off

Spend ten minutes a day on image-based review. Show yourself a picture of a rash, a joint X-ray description or a muscle biopsy, say the diagnosis and the mechanism out loud, then check. Dermatology and musculoskeletal items are among the most visual on the exam, and the skill of naming a pattern quickly is built by repetition, not by reading.