Pseudogout

Chondrocalcinosis Knee ArthroscopyChondrocalcinosis Glenoid Arthroscopy

 

Definition

 

Pseudogout 

- Calcium Pyrophosphate Dihydrate (CPPD) crystals

- inflammatory arthritis of older individuals 

 

Chondrocalcinosis

- refers to any calcium in cartilage / menisci

 

Epidemiology 

 

M:F 2:1

 

Patient > 50

 

Sometimes familial

 

Association

 

DM

Hypothyroidism

Gout

Hyperparathyroidism

Haemochromatosis

Pernicious Anaemia

Onchronosis

 

Pathology

 

CPPD deposited in

- joint capsule

- articular cartilage

- fibrocartilage / meniscus

 

Crystals seen at margin of degenerating cartilage

- pyrophosphate generated at chondrocyte surface in abnormal cartilage

- combine with calcium to form crystals

 

Occasionally the crystals are released into the joint & an acute arthritis results

- activation of vasoactive & chemotactic factors

- neutrophils attracted & phagocytose crystals

- release of lysosomal enzymes into joint fluid

 

Chronic chondrocalcinosis predisposes to development of 2° OA 

- crystals embedded in articular cartilage have desiccating effect

 

Clinical presentations

 

1. Asymptomatic Chondrocalcinosis

 

Majority of people

- incidental finding

- calcium of menisci

- usually involved with degenerative changes

 

2. Pseudogout

 

Rapid onset inflammatory arthritis

- peak in 24/24

- subsides in 1/52

 

May be provoked by

- trauma

- surgery

- illness

 

Usually affects large joints

- Knee > Shoulder > Wrist

- typically monoarticular

- less pain than gout

 

3. Chronic CPPD Arthropathy

 

OA 2° CPPD

 

Pseudo-Osteoarthritis

- polyarticular disease like OA

- in hips & knees

- due to CPPD in cartilage altering the biomechanics

 

In more unusual joints for OA

- ankles, shoulders, elbows

- very common in PFJ

- has radiodense crystals

 

4. Pseudo- Rheumatoid Arthritis

 

Acute synovitis & chronic arthritis

- rapidly progressive joint destruction

 

Synovial Fluid

 

CPPD crystals seen extracellular & in neutrophils

- rhomboidal

- weakly positively birefringent 

- IE Blue parallel to 1° order red filter & 135° to polarizer

 

X-ray

 

Chondrocalcinosis

 

Calcium in fibrocartilage & CT 

- punctate densities

- menisci / TFCC / pubis / annulus

 

Findings of OA usually present

 

Unusally joints

- PFJ

 

Screening Bloods

 

Ca / PTH

U&E

Serum Fe / Fe studies

TFT

Serum Alk Phos

 

Differential Diagnoses

 

Hyperparathyroidism          

 

X-rays show subperiosteal erosions

 

Blood tests show hypercalcemia / increased PTH

 

Ochronosis 

 

Often severely affects spine / shoulders / hips / knees

 

Hemochromatosis

 

Disorder where iron deposited in many tissues including articular cartilage

- concomitantly get cirrhosis of the liver / CCF /diabetes / bronze skin

- chondrocalcinosis often prominent feature

- calcification of multiple joints and discs

- serum Fe and IBC raised

 

Management

 

Options

 

1.  NSAIDS

2.  HCLA

3.  Colchicine

- 80% response 

4.  Joint washout

 

Joint washout

 

Don't debride / perform synovectomy

Worsens symptoms

 

Chondrocalcinosis KneeChondrocalcinosis Knee 2Chondrocalcinosis Knee 3