What is Diffuse Idiopathic Skeletal Hyperostosis (DISH)?

From the Guidelines

DISH, or Diffuse Idiopathic Skeletal Hyperostosis, is a condition characterized by abnormal bone growth along the spine and other areas of the skeleton, primarily affecting older adults over 50 years old, with a higher prevalence in men. The condition is often discovered incidentally on X-rays ordered for other reasons, as many people with DISH have minimal symptoms.

Key Characteristics of DISH

• It causes calcification and hardening of ligaments and tendons where they attach to bone, particularly along the right side of the spine 1.
• The main symptoms include stiffness, limited range of motion, and mild to moderate pain, especially in the upper back.
• Some patients may experience difficulty swallowing if bone growths develop in the neck area.

Diagnosis and Treatment

• DISH is often diagnosed using X-rays, which can reveal abnormal bone growth and calcification.
• Treatment focuses on symptom management through physical therapy, pain medications like NSAIDs, and maintaining a healthy weight to reduce stress on affected joints.
• The exact cause of DISH remains unknown, though factors like diabetes, obesity, and certain metabolic conditions appear to increase risk 1.

Important Considerations

• Unlike inflammatory arthritis, DISH doesn't cause joint inflammation or erosion but rather creates excess bone formation outside the joints.
• Regular radiological evaluations are not required for patients with DISH, but targeted X-rays may be informative for atypical musculoskeletal pain 1.

From the Research

Definition and Characteristics of DISH

• Diffuse idiopathic skeletal hyperostosis (DISH) is a systemic condition characterized by the ossification and calcification of ligaments and entheses 2.
• It is observed on all continents and in all races, but most commonly in men over 50 years of age 2.
• DISH is often asymptomatic, but can lead to symptoms such as pain, stiffness, reduced range of articular motion, and dysphagia 2, 3.

Clinical Relevance and Diagnosis

• The presence of DISH is associated with underlying metabolic disease, and can increase the risk of unstable spinal fractures 2, 3, 4.
• Diagnosing DISH is of clinical importance, as it can impact the management of patients with spinal or extraspinal ossifications 3, 4.
• The diagnosis of DISH is based on the presence of multiple contiguous fully formed bridging ossifications, which can be identified through radiographic imaging 2, 3.

Pathogenesis and Associated Factors

• The pathogenesis of DISH is currently unknown, but it has been associated with older age, male sex, obesity, hypertension, atherosclerosis, and diabetes mellitus 4.
• Local fibroblasts, chondrocytes, collagen fibers, and calcified matrix are likely influenced by genetic, vascular, metabolic, and mechanical factors in the development of DISH 4.
• The presence of DISH has been linked to an increased risk of spinal fractures, metabolic syndrome, coronary and aortic disease, and respiratory effects 3, 4.