Musculoskeletal Disorders

• No man’s land in flexor tendon → Zone 2

• Infertility workup → WHO grade 2 is most common

• BE FAN VEIN

• Patellar clunk syndrome

HLA associations

• 51 (HLA B51) yr old Nolan (Anti enolase) on a Bus (behcets)

Loose Bodies in joints

• M/c/c in adults: Osteoarthritis

• M/c/c in children: Osteochondritis dissecans

• O/c: RA, Charcots arthritis, FBs

Rheumatoid Arthritis (RA)

• 51 (HLA B51) yr old Nolan (Anti enolase) on a Bus (behcets)

Synovial Disease

• Type: Most common inflammatory arthritis.

General Features

• Rheumatoid factor: IgM Against Fc part of IgG (MRF → M against G)

• Prevalence: Female > Male.

• Characteristic: 
• Erosive arthritis (destroys joints),
• unlike SLE → non-erosive.

• Nature: Chronic autoimmune multisystem disease.

• Symptoms:
• Involvement can be bilateral.
• Initial presentation:
• Only wrist joint may show redness/inflammation.
• PIP inflammation may not be noticed.
• Morning stiffness.
• Symmetrical peripheral joint involvement.

• Prominent periarticular osteopenia.

Joints Involved

• Atlanto axial dislocation → Specific

• Upper Limb: 
• MCP > Wrist > PIP

• Lower Limb: 
• Knee and Hip.

Diagnosis

• Elevated CRP and ESR

• Rheumatoid Factor/RA factor
• Most sensitive marker.
• IgM class antibody,
• 5% false positive,
• can be positive in sore throat

• Anti-CCP (Cyclic Citrullinated Peptide): 
• Most specific marker.
• positive → erosive arthritis

Monitoring:

• Follow up for next 6 weeks.

X-ray Findings

1. Narrowed Joint Space.

2. Osteopenia

3. Juxta-articular Osteoporosis: 
• Generalized bone thinning near joints.

4. Marginal Erosions.

5. Absence of Sclerosis/Osteophytes
• differentiates from OA

Deformities in RA

• Involves small joints of hand:
• MCP > wrist joint > PIP
• Note: Rheumatic fever involves large joints (ankle, knee).

1. Boutonniere's Deformity: 

• Flexion at PIP joint.

• Hyper extension at DIP joint.

2. Swan-neck Deformity: 

• Flexion at DIP joint.

• Hyper extension at PIP joint.

• SFD (Street food of delhi) → Swan neck → Flexion at distal

 

3. Z thumb Deformity: 

• Fingers deviated to ulnar side;

• metacarpals deviated to radial side.

• Z-thumb deformity/Hitch Hiker thumb deformity.

• Different from Z-line deformity (ulnar deviation).

NOTE:

• Mallet finger:



• Flexion at DIP, no deformation at PIP.
• Seen in wicket-keepers (injury to extensor tendon, not part of RA).

 

4. Windswept Deformity: 

• Both knees face the same side.

 

• Windswept deformity
• (valgus on one side, varus on the other).
• Children/Overall:
• Rickets (m/c).
• Adults:
• Rheumatoid Arthritis (m/c)
• Mnemonic: Kaatadichapo kunjnugal rocket (ricket children) pole poi, Adult Room adachitt (RA)

5. Hallux Valgus: 

• Lateral deviation of the great toe.

6. Hammer Toes: 

• Deformity of the
1. second,
2. third, or
3. fourth toe,
4. where the toe is bent at the middle joint.

7. Bilateral Genu Valgum (knock-knees).

Management (erosive arthritis):

• Aggressive treatment.

• NSAIDs

• Triple therapy:
• Start with Methotrexate (MTX).
• If good response
• continue.
• If no response,
• add Hydroxychloroquine and Sulfasalazine.

Extra-Articular Manifestations

• Rheumatoid Nodules:
• Most common extra-articular manifestation.
• Extensor distribution (olecranon process, occiput, spine tips, dorsum of hand).

• Eye Manifestations:
• Keratoconjunctivitis sicca.

• Spinal Risk:
• Avoid yoga/spinal movements/sports (neck rotation, headstand).
• Risk of atlantoaxial subluxation
• Cause spinal cord compression and quadriplegia.

• Cardiovascular Manifestations:
• Rheumatoid nodules in heart
• between SA and AV node, causing 1st-degree heart block
• Damage to myocardium.
• Accelerated atherosclerosis
• important cause of death
• Note: Aschoff nodules in rheumatic fever.

• Respiratory Manifestations:
• Rheumatoid nodules in lungs.
• Pleuritis/pleural effusion (exudative).
• Light’s criteria for exudative effusion:
1. Pleural fluid protein/serum protein >0.5
2. Pleural fluid LDH/serum LDH >0.6
3. Pleural fluid LDH >2/3rd upper reference limit of normal for serum.

• Hematological:
• Anemia of chronic disease (normocytic normochromic & microcytic hypochromic).

• Peripheral Nervous System:
• Mononeuritis multiplex (multiple peripheral nerves involved).

Morning stiffness d/ds:

• 2 conditions
1. Severe in RA
• difficulty brushing teeth,
• getting late for office
2. Ankylosing spondylitis
• stiffness reduces with activity

Scleromalacia Perforans

• Description:
• Anterior necrotising scleritis without inflammation.

• Presentation:
• No redness/pain,
• progressive atrophy → leading to scleral perforation.

• Most common in:
• Women with rheumatoid arthritis.

• If no h/o RA → Staphyloma

• For B cell ⛔ → R/o hep B

• For TNF α ⛔ → R/o TB

• NSAIDs and Steroids
• ↓ Pain and Inflammation
• No effect on disease Progression
• Fast acting

• DMARDs or SAARDs
• Slow down the disease progression
• Slow acting
• Used now
1. Methotrexate (DOC)
2. Sulfasalazine
3. Leflunomide
4. Hydroxychloroquine
• Mnemonic - sulfikkar () met () and left () gave water with chlorine ()

• Biological agents
• TNF alpha inhibitors

Reactive Arthritis (Reiter's Disease)

• HLA Association: HLA-B27 and B51

Definition

• *Joint inflammation caused by sterile inflammation reaction
• following a recent entropathic or urogenital infection**.

Triggered by:

• GI infection,

• non-gonococcal urethritis (sexually acquired reactive arthritis),

• HIV patients

Triad of Features

Mnemonic:

• Cant see
• Conjunctivitis (non-gonococcal, esp. Chlamydia)

• cant pee
• Urethritis
• Circinate Balanitis:
• Superficial erosions on glans/penis

• cant climb a tree
• Polyarthritis:
• >1 month,
• non-suppurative,
• lower limbs (post GI/urethritis infection)



• Keratoderma Blennorrhagicum:
• Hyperkeratotic papules on palms and soles

Treatment

• Physical therapy and rehabilitation.

• NSAIDs.

• Intra-articular steroid injection in severe cases.

Uveitis A/w HLA B27 - associated arthritis = JRAP

• Ankylosing Spondylitis

• Psoriatic arthritis

• Reiter's syndrome/Reactive arthritis.

• JIA

Also Known As:

• Marie-Strümpell Disease.

• Bechterew's Disease.

Schober test:

• 2 marks
• 1st → mark at posterior superior iliac spine +
• 2nd → 10cm above

• Reveals spine involvement (flexion not possible).

• Normal person:
• Spine flexible,
• gap increases to 15cm on bending

• In patient:
• Flexion limited

Antibody:

• Targets cytosolic 5' nucleotidase.

Pathology: 

• Enthesopathy
• inflammation where tendons or ligaments attach to bone
• Cause enthesitis affecting Achilles tendon

Presentation

• Young male with low backache.
• Morning Stiffness: 
• Improves with activity (distinguishes from RA).
• When he stands or puts his foot on the ground, there is pain in the foot or sole.
• Decreased Lumbar Spine Movement.
• Sacroiliitis:
• Juxta-articular erosion.
• Blurring of margins.
• Sclerosis leading to joint fusion.

• Involvement: Axial > Peripheral joints.
• Most commonly affects Sacro-iliac (SI) joint (m/c).
• Also affects spine and hip.
• Starts in sacro-iliac joint.
• Spine fused by syndesmophytes anteriorly and posteriorly.

• History of red eye (anterior uveitis - extra-articular manifestation).

X-ray

• It shows sacroiliitis.

• If the disease is progressive, it shows a large number of osteophytes present.

• Calcification present in paravertebral ligaments.
• Causes bamboo spine.

Bamboo Spine: 

• Fusion and squaring of the spine due to:
• Calcification between vertebrae, restricting movement.
• Inflammation → syndesmophyte formation
• (vertical/bridging syndesmophytes)
• → fusion anteriorly and posteriorly

Dagger Sign: 

• Calcification of only the interspinous ligament.

 

Trolley Track Sign: 

• Calcification of paraspinal ligaments and interspinous ligaments.

Enthesopathy

• Tendons like the Achilles tendon involved → tendinitis
• complaints of heel pain.

Cardiovascular Manifestation

• Valvular aortic regurgitation.

Lung Manifestations

• Stiffness of costochondral joint.

• Extra parenchymal restrictive lung disease.
• No proper exhalation
• So residual volume is increased.

• In contrast, in parenchymal restrictive lung disease, there is fibrosis of the lung.

HLAB27 Test = JRAP

• Positive.

• HLAB27 is also Positive in:
• Juvenile rheumatoid arthritis.
• Ulcerative colitis.
• Reiter syndrome/Reactive arthritis.

MRI:

• Most sensitive.
• Bone marrow edema is seen first.
• STIR-MRI identifies bone marrow edema.

Clinical Tests

• Decreased Chest Movements.

For Testing Lumbar Spine Motility:

• Schober Test/Modified Schober Test:



• Measures distance between two points on the spine
• from standing to full flexion;
• in AS,
• distance does not increase due to fusion.

• Note on Non-Erosive Arthritis (e.g., SLE): 
• Joint inflammation occurs,
• no loss of articular cartilage or destruction of subchondral bone.

For Sacroiliitis:

• Gaenslen's Test.

• FABER Test (Flexion, Abduction, External Rotation) / Figure-of-4 Test.

• Pump Handle Test.

Treatment

• NO ROLE OF DMARDS

• Infliximab.

• NSAIDs → Biologicals

• Monoclonal antibody TNF α agonist. Reactive arthritis.

Gout

Gout as a Disease

• Precipitates crystals in the joint space of the patient.

• local erosive lesion
• 1st metatarsal phalangeal joint in the patient.

• Because of recurrent flare up of acute gout.

Pathogenesis

• Metabolism: 
• Abnormality in purine metabolism.

• Uric Acid (UA): 
• Increased uric acid production (normal values: 3.5 to 6.5 mg/dL).

• Mechanism: 
• Sudden change in UA levels
• Deposition of crystals in cold peripheral joints
• Local inflammatory reaction
• Collateral damage and pain.

Clinical Features

• Most Common Joint: 
• First MTP joint of the big toe.

• Preponderance:
• Middle-aged, male > female.
• Associated with consumption of alcohol, red meat, and chemotherapy.

• Symptoms:
• Acute gouty pain,
• often forming tophi (urate crystal deposits).

Joint Aspiration: 

• IOC (Investigation of Choice) for acute gouty attack.

• Fluid-Turbid.

Characteristics of Crystals:

• Monosodium Urate (MSU).

• Needle-shaped.

• Negatively birefringent on polarizing light microscopy
• crystals appear yellow when parallel to the filter

Pseudo gout

• Positive birefringence crystals in polarised microscopy are seen in
• Rhomboid shaped
• Ca pyrophosphate

• That involves knee joint.

• Chondrocalcinosis → Calcification of meniscus

• Mnemonic: Miss U → Needles (needle-shaped), Negatively birefringent, Yellow (when parallel).

X-ray Findings:

• 1st MTP.
• Podagra.

• On X-ray foot:
• Overhanging/Martel's Sign/Rat bite erosions: 
• Erosions with overhanging edges
• Punched-out Lesions.

• Joint Destruction.

• In the skull, vertebra, and pelvis are usually present in multiple myeloma.

DECT (dual energy)

• Helps identify uric acid deposits.

Tests Done Are

• Serum uric acid: Elevated.
• In both overproducer & in under excreter.

• 24 hours urinary uric acid value is used to differentiate b/w
• Overproducer &
• Under excreter

Management

---

Acute Gout Attack:

Chronic Gout:

Drugs decreasing production of uric acid

Drugs increasing excretion of uric acid (Uricosuric agents)

Drugs increasing metabolism of uric acid

Allopurinol

• DOC:
• Chronic gout
• Tumor Lysis Syndrome
• Lesch-Nyhan Syndrome
• Defective purine metabolism
• Organ transplant

• Side effects:
• Hypersensitivity (severe):
• Stevens-Johnson Syndrome (associated with HLA-B*5801)
• Orotate decarboxylase inhibition:
• Causes orotic aciduria
• DRESS syndrome
• Mnemonic: Allu (Allopurinol) arjun → Johnson (SJS) powder → Dress up () and Oridath irunn (Orotic aciduria) muthram ozhich

Loose Bodies in joints

• M/c/c in adults: Osteoarthritis

• M/c/c in children: Osteochondritis dissecans

• O/c: RA, Charcots arthritis, FBs

• 51 (HLA B51) yr old Nolan (Anti enolase) on a Bus (behcets)