From the Guidelines
Chondrocalcinosis of the knee is a condition characterized by the deposition of calcium pyrophosphate crystals in the cartilage of the knee joint, often presenting with asymptomatic chondrocalcinosis or acute calcium pyrophosphate crystal arthritis, and managed with a focus on symptom relief rather than elimination of the crystals. This condition can manifest in different clinical phenotypes, ranging from asymptomatic to chronic symptoms and functional impairment, making management challenging 1. The deposition of calcium pyrophosphate crystals can trigger painful inflammatory episodes, known as pseudogout or calcium pyrophosphate deposition disease (CPPD).
Key aspects of chondrocalcinosis of the knee include:
- Incidental detection on X-rays as thin lines of calcification within the cartilage
- Potential to trigger painful inflammatory episodes when crystals shed into the joint fluid
- Management focusing on symptom relief, as there is currently no specific treatment to eliminate CPP crystals 1
- Importance of maintaining joint mobility through regular, gentle exercise and physical therapy for long-term management
Treatment options for acute flares and long-term management may include:
- NSAIDs for symptom relief
- Colchicine for acute attacks and prevention in recurrent cases
- Joint aspiration with corticosteroid injection for severe pain
- Weight management and screening for associated metabolic disorders in some patients.
From the Research
Definition of Chondrocalcinosis
Chondrocalcinosis refers to the deposition of calcium pyrophosphate crystals within cartilage or fibrocartilage, as visualized on plain radiograph 2. It is an arthropathy caused by deposits of calcium pyrophosphate-dihydrate microcrystals (CPPD) in the joints and occasionally in the tendons and ligaments 3.
Clinical Features
The clinical features of chondrocalcinosis are various, with two common presentations being:
- Acute synovitis (pseudogout)
- Chronic arthritis, which can lead to severe disability 2 Other clinical entities include:
- An acute arthritis resembling gout or septic arthritis
- An inflammatory polyarthritis suggesting rheumatoid arthritis
- A benign polyarthrosis
- A destructive course capable of seriously damaging one or several joints 3
Risk Factors
The main risk factor for the occurrence of sporadic chondrocalcinosis is aging 2. The prevalence of chondrocalcinosis varies from 7 to 10% in people aged around 60 years old 2. Primary metabolic disorders or familial predisposition should be considered if chondrocalcinosis occurs in patients younger than 60 years 2, 4. Metabolic disorders that predispose to secondary chondrocalcinosis include hereditary hemochromatosis, hyperparathyroidism, and hypomagnesemia 2, 4.
Diagnosis and Treatment
Definitive diagnosis of chondrocalcinosis is allowed by identification of calcium pyrophosphate (CPP) crystals in synovial fluid 4. X-Rays are the most frequent imaging used to detect chondrocalcinosis 4. Treatment of CPP arthritis includes:
- Application of ice
- Rest
- Joint aspiration
- Intra-articular injection of corticosteroids
- Oral NSAIDs (used cautiously, particularly in the elderly)
- Prophylaxis against frequent recurrent acute CPP crystal arthritis with low-dose oral colchicine 4