📚 Internal Medicine Osce Clinical Skills Rheumatology Osce

📚 Lecture Overview

This summary provides a targeted clinical skills review for OSCE stations focusing on rheumatological physical examinations: Systemic Sclerosis (SSc), Systemic Lupus Erythematosus (SLE), Rheumatoid Arthritis (RA), Knee Pathology, and Ankylosing Spondylitis (AS). It details step-by-step inspection, integrated palpation techniques, specific range of motion tests, and special diagnostic maneuvers needed to master rheumatology clinical encounters.

🎯 Key Concepts & Definitions

• Sclerodactyly: Thickening and tightness of skin on the fingers, evolving from an edematous (puffy) phase to an indurated (fibrotic) phase.
• Raynaud's Phenomenon: Vasospastic vascular response to cold or stress displaying three phases: Pallor (white/vasospasm), Cyanosis (blue/carboxyhemoglobin accumulation), and Hyperemia (red/reperfusion).
• Telangiectasia: Dilated abnormal capillaries that blanch on direct pressure and show slow capillary refill, differentiating them from petechiae and spider angiomas.
• Livedo Reticularis: A net-like, purple mottled skin pattern indicating sluggish blood flow, strongly associated with Antiphospholipid Syndrome.
• Caput Ulnae (Piano Key Sign): Prominence and instability of the distal ulnar head resulting from wrist ligament laxity in rheumatoid arthritis.
• FABER (Patrick's) Test: A diagnostic stress test (Flexion, Abduction, External Rotation) for the sacroiliac joint where posterior lower back pain indicates SIJ pathology.
• Modified Schober Test: An objective measurement of lumbar flexion measuring the expansion of a marked 15 cm spinal segment upon full forward bending.

📖 Main Content

1. Systemic Sclerosis (SSc) Examination

General Examination Principles

• SSc clinical stations present full cases (face and hand) requiring integrated inspection and palpation simultaneously (e.g., palpating Raynaud's during visual inspection).
• Command Logic:
• "Inspect" = Do not touch or extend the limbs.
• "Palpate" = Touching and extending limbs is allowed.

Facial Inspection & Palpation

• General Appearance: Elongated face, younger look due to feature preservation.
• Hair: Alopecic patches on the scalp.
• Forehead: Loss of skin corrugations and wrinkles; smooth skin surface.
• Pinch Test: Attempt a normal skin pinch. Inability to pinch skin (tethering) occurs due to fibrous tissue tethering to underlying structures with loss of skin elasticity.
• Eyebrows & Eyes: Loss of outer third of eyebrows. Sunken eyes with symptoms of dry eyes and gritty sensation. Ask if the patient can cry.
• Nose: Thin, pinched-like nose. Ask if the nose shrank in size over time.
• Nasolabial Folds: Flattened folds.
• Mouth Area: Purse-like lips with radial furrowing/crumpling, thin lips (fish-like mouth).
• 3-Finger Test: Ask patient to insert three fingers vertically into the mouth. Inability indicates microstomia (narrow oral aperture).
• Intra-oral Exam: Poor oral hygiene and tooth loss caused by gingival atrophy from fibrosis and inability to brush due to microstomia.

Key Skin Features (Face, Trunk, & Hands)

• Telangiectasia: Visible red spots/vessels.
• Blanches on pressure (distinguishes from non-blanching petechiae/purpura).
• Slow refill (distinguishes from rapid-refill spider angioma caused by hyperestrogenemia).
• Salt & Pepper Pigmentation: Disorder of melanin showing mixed hyperpigmented (dark) and hypopigmented (light) areas on the trunk, hands, and face.
• SSc vs. Vitiligo: In SSc, neither dark nor light skin is normal. In Vitiligo, dark skin is normal and light skin is depigmented. Vitiligo lacks systemic features.
• Calcinosis: Hard subcutaneous calcium deposits indicating active disease. Complications include cellulitis and nerve, muscle, or joint compression.

Hand Inspection & Palpation

• Skin & Appendages: Shiny, waxy skin with tethering; loss of digital hair; loss of sweating.
• Temperature: Assess using the dorsum of the hand (typically cold).
• Raynaud's Phenomenon: Look for three classic color changes: Pallor $\rightarrow$ Cyanosis $\rightarrow$ Hyperemia.
• Flexion Contractures: Fixed flexion posture of fingers without joint destruction (unless overlapping with RA, OA, or PsA).
• Fingertip Findings:
• Digital Ulcers: Active open sores or crusts.
• Pitting Scars: Healed ischemic ulcers.
• Resorption of Terminal Phalanges: Shortened fingertips ("eaten away" appearance).
• Sclerodactyly: Phase 1 is edematous (puffy fingers without joint swelling); Phase 2 is indurated (fibrotic).
• Tendon Rub: Palpate coarse crepitus over tendons during joint movement.
• Palms: Palmar erythema (thenar/hypothenar redness with central palmar pallor) and thin atrophic skin showing underlying tendons.

2. Systemic Lupus Erythematosus (SLE) Manifestations

Cutaneous & Vascular Findings

• Malar Rash: Acute cutaneous rash on cheeks and nose bridge that spares the nasolabial folds and worsens with UV light.
• Discoid Rash: Chronic plaque with hyperpigmented rims and lighter atrophic centers; found on face, scalp, and ears.
• Photosensitive Rash: Occurs on sun-exposed regions (V-sign of neck, dorsum of hands).
• Vasculitis:
• Nail Fold Infarcts: Tiny black or brown dots in nail folds or cuticles (tissue necrosis).
• Palpable Purpura: Raised, non-blanching red/purple spots on lower legs.
• Livedo Reticularis: Mottled, net-like purple skin pattern associated with Antiphospholipid Syndrome.
• Oral/Nasal Ulcers: Painless red patches or shallow erosions, typically on the hard palate.

Head & Neck Exam

• Alopecia:
• Diffuse Non-Scarring: General hair thinning and fragile "lupus hair" at frontal hairline; indicates an active disease flare and regrows upon treatment.
• Discoid Scarring: Smooth, shiny white patches with lost follicular openings; permanent hair loss.
• Cushinoid Features: Caused by Prednisolone therapy—moon face, buffalo hump at base of neck, hirsutism, and steroid acne.
• Periorbital Puffiness: Eyelid edema indicating Nephrotic Syndrome from Lupus Nephritis.
• Secondary Sjögren's Syndrome: Seen in ~30% of SLE patients. Presents as dry eyes (keratoconjunctivitis sicca), dry mouth (xerostomia), rapid dental caries near gum lines, and parotid gland enlargement.

3. Rheumatoid Arthritis (RA) Hand Examination

Inspection (Resting on Pillow)

• Subcutaneous Rheumatoid Nodules: Firm, well-circumscribed, non-tender nodules located around joint lines on extensor surfaces (never directly on the joint line).
• Muscle Wasting: Interossei wasting (guttering sign), thenar, and hypothenar wasting.
• Joint Swelling Pattern:
• MCPs: Symmetric swelling (count by asking patient to make a fist).
• PIPs: Fusiform (spindle-shaped) swellings.
• DIPs: Spared in RA (DIP involvement suggests Osteoarthritis, Psoriatic Arthritis, Gout, or Trauma).
• Wrists: Boggy synovium.
• Classic Deformities:
• Swan Neck: Flexed DIP + Extended PIP.
• Boutonnière: Extended DIP + Flexed PIP.
• Z-Shaped Thumb: Flexed MCP + Extended IP joint.
• Zig-Zag Hand: Radial wrist deviation + Ulnar MCP deviation.
• Caput Ulnae: Prominent distal ulnar head due to laxity of wrist ligaments.

Palpation & Movement

• Palpation Systematic Scheme (TTCS): Temperature, Tenderness, Crepitus, Swelling.
• MCP Assessment: Squeeze test across knuckles for tenderness; bimanual exam with MCPs flexed 30 degrees to open the joint line groove.
• PIP/DIP Assessment: Bi-digital four-point technique (thumbs and index fingers pushing fluid).
• Swelling Character: Soft = Cystic/Effusion; Doughy = Synovitis; Hard = Bone deformity/Osteophytes.

4. Knee Joint Examination

Inspection & Palpation

• Standing Inspection: Check alignment for Genu Valgum (knock-knees) or Genu Varum (bow-legs).
• Popliteal Fossa: Inspect for Baker's Cyst (smooth swelling). A ruptured Baker's cyst mimics DVT; differentiate using Doppler Ultrasound (patent veins = cyst; thrombus = DVT).
• Muscle Assessment: Quadriceps wasting produces flattening or guttering above the knee.
• Palpation (TTCS): Knee flexed to $30°$. Palpate joint line, quadriceps tendon, patellar tendon, and popliteal space.

Effusion Assessment Methods

1. Bulge / Swipe Test (Mild to Moderate Effusion):
   - Stroke upward on the medial side of the knee to clear fluid into the suprapatellar pouch.
   - Stroke downward on the lateral side.
   - Positive Result: A fluid wave or ripple appears on the medial joint line.
2. Patellar Tap Test (Large / Severe Effusion):
   - Milk the suprapatellar pouch downward with one hand to compress fluid behind the patella.
   - Tap the patella sharply against the femur with two fingers of the other hand.
   - Positive Result: Patella clicks against the femoral condyle and floats back up.

Movement Interpretation

• Limited Active + Improved Passive ROM: Peri-articular pathology or muscle pain.
• Limited Active + Limited Passive ROM: True articular joint pathology or fixed joint contracture.

5. Ankylosing Spondylitis (AS) & Spine Examination

Visual Deformities & Posture

• Skin Check: Look for psoriatic plaques (red patches with silver scales) on extensor surfaces.
• Spinal Curvatures: Loss of cervical lordosis, exaggerated thoracic kyphosis, loss of lumbar lordosis.
• Muscle Wasting: Paraspinal muscle atrophy causing the spinous processes to protrude in a deep gutter; trapezius atrophy leading to "square shoulders."
• Classic Zig-Zag Posture: Forward-flexed head, thoracic kyphosis, protruded abdomen, flexed hips, and flexed knees.
• Chest & Lungs: Intercostal muscle atrophy due to restrictive chest expansion from rib/spine fusion; increased risk for apical lung fibrosis.

Segmental Spine Examinations

Spine Region ───► Cervical: Spinous process tenderness (C2-C7), ROM, Occiput-to-Wall test

             ───► Thoracic: Seated rotation, Chest expansion test (Normal > 5 cm)

             ───► Lumbar:   Schober test, Modified Schober test, Finger-to-Floor test

• Chest Expansion Test: Measured at the nipple line (males) or below breasts (females) during deep expiration vs. deep inspiration. Normal is $>5 cm$; abnormal restriction is $<2.5 cm$.
• Occiput-to-Wall Test: Patient stands barefoot with heels, buttocks, and shoulders touching the wall, looking straight ahead. Normal distance = $0 cm$.
• Tragus-to-Wall Test: Measures forward head posture. Normal distance = $<15 cm$.

Lumbar Mobility Tests

• Finger-to-Floor Test: Measures global spinal flexion. Measures distance from middle finger to floor (used for 6-month monitoring).
• Classic Schober Test:
  1. Find sacral dimples of Venus (PSIS) and mark the midline connecting line.
  2. Mark a point $10 cm$ above the midline mark.
  3. Patient flexes forward completely.
  4. Normal: Distance increases by $>5 cm$ (total distance $>15 cm$).
• Modified Schober Test:
  1. Mark the L5/S1 joint line between the sacral dimples.
  2. Mark $10 cm$ above AND $5 cm$ below (initial total = $15 cm$).
  3. Patient flexes forward completely.
  4. Normal: Total distance increases to $≥ 20 cm$ (an increase of $≥ 5 cm$).
• Lateral Schober Test:
  1. Mark intersection of iliac crest and mid-axillary line; mark a second point $20 cm$ above.
  2. Patient bends sideways away from the marks.
  3. Normal: Distance increases from $20 cm$ to $25 cm$.

Sacroiliac Joint (SIJ) Testing

Rule: Positive SIJ tests must reproduce pain in the posterior lower back/gluteal region. Pain in the groin indicates hip joint pathology.

1. Direct Percussion: Press thumb or strike fist directly over sacral dimples.
2. Pelvic Compression & Distraction: Compress iliac crests inward (compresses SIJ) or push them outward (distracts SIJ).
3. FABER / Patrick's Test: Flexion, Abduction, External Rotation of hip with ankle on opposite knee. Push down on bent knee while stabilizing opposite ASIS.
4. Gaenslen's Test: Patient lies on edge of bed; dangling outer leg is hyperextended while inner leg is flexed to chest.
5. Modified Gaenslen's Test: Side-lying position for patients with severe kyphosis.
6. Pump Handle Test: Direct knee towards the opposite shoulder to stress the SIJ.
7. Gillis Test: Prone position; stabilize buttock and hyperextend opposite leg.

📊 Visual Learning

💡 Important Points to Remember

• In Systemic Sclerosis, inspection and palpation are integrated; do not wait to touch when checking Raynaud's or skin tightness.
• Telangiectasia vs. Spider Angioma: Telangiectasias show slow refill and occur on face/hands in SSc. Spider angiomas show rapid refill and occur in SVC distribution (liver failure).
• Salt and Pepper Pigmentation vs. Vitiligo: Vitiligo leaves normal skin dark and light skin depigmented without systemic disease; SSc alters pigmentation in both dark and light areas and presents with systemic features.
• Rheumatoid Nodules are found on extensor surfaces around joint lines—never directly on the joint line itself.
• RA spares the DIP joints. DIP involvement points toward Osteoarthritis, Psoriatic Arthritis, Gout, or Trauma.
• In Carpal Tunnel Syndrome (Tinel's/Phalen's), palmar sensation is preserved because the palmar cutaneous nerve branch arises proximal to the flexor retinaculum.
• Ruptured Baker's Cyst vs. DVT: Both present with acute painful calf swelling; Doppler Ultrasound is required to differentiate (patent deep veins in cyst rupture).
• Chest Expansion in AS: Normal is $>5 cm$; restriction $<2.5 cm$ indicates severe axial disease and restrictive lung mechanics.
• SIJ Pain Location Trap: Pain elicited in the groin during FABER/Gaenslen's indicates hip pathology; pain in the posterior lower back/buttock indicates true SIJ pathology.

⚠️ Common Exam Questions & Traps

How Examiners Trick Students in MCQs & OSCEs:

1. DIP Joint Questions: Examiners present a case of hand deformities with DIP joint involvement and ask for the diagnosis. If DIPs are affected, select OA or PsA, NOT Rheumatoid Arthritis.
2. Telangiectasia vs. Purpura vs. Spider Nevi:
   - Petechiae/Purpura: Non-blanching.
   - Spider Angioma: Blanching, rapid refill, upper body distribution.
   - Telangiectasia: Blanching, slow refill, facial/hand distribution.
3. Malar Rash Flaws: Examiners will describe a facial rash and explicitly state whether it involves or spares the nasolabial folds. SLE malar rash spares the fold; Rosacea or Seborrheic dermatitis involves it.
4. FABER Test Pain Location: Questions describe FABER test causing groin pain and list SIJ options. Remember: Groin pain = Hip joint; Buttock/Lower back pain = Sacroiliac joint.
5. Ruptured Baker's Cyst Trap: A patient with RA develops sudden calf pain and swelling after exercise. Examiners will try to trick you into diagnosing DVT or starting anticoagulation. The correct initial diagnostic step is Doppler Ultrasound to confirm a Baker's cyst rupture.

📝 Quick Review Checklist

I can perform the 3-finger test and pinch test for Systemic Sclerosis.
I know the difference between Telangiectasia, Spider Angiomas, and Purpura.
I can differentiate SSc Salt & Pepper pigmentation from Vitiligo.
I can identify the 3 phases of Raynaud's Phenomenon.
I can identify and describe classic RA hand deformities (Swan Neck, Boutonnière, Z-thumb, Caput Ulnae).
I remember that RA spares the DIP joints.
I can perform and interpret Tinel's, Phalen's, and Piano Key tests.
I know when to use the Bulge/Swipe Test versus the Patellar Tap Test for knee effusion.
I can perform and calculate the Modified Schober Test for lumbar flexion.
I know how to differentiate hip pain from sacroiliac joint pain during FABER and Gaenslen's testing.