Synonym: Forestier's disease

Diffuse idiopathic skeletal hyperostosis (DISH) is a tendency for ossification of ligaments, tendons and joint capsule insertions, most often affecting the spine. Calcification of the longitudinal ligaments (particularly anterior) can often produce the radiological appearance of "wax dripping from a candle", distinct from the vertebral bodies.¹ The thoracic spine is mainly affected but it can also affect the lumbar and cervical spine, and other areas of the skeleton. The tendon/osseous junctions are occasionally affected around the elbow, patella, calcaneus, hip and knee joints. The cause is unknown.

Epidemiology

• The prevalence in European men over the age of 50 years is 5.8% and in women is 1.3%.²
• Uncommon in patients younger than 50 years and extremely rare in patients younger than 40 years.

Presentation

• Is usually asymptomatic and discovered by chance on X-rays or CT/MRI scans.
• Symptoms may include pain, stiffness and restricted movements of the affected areas.

Investigations

• X-rays:
  • Characteristic appearance of "wax dripping from a candle", distinct from the vertebral bodies.
  • Thoracic vertebrae are involved in 100%, lumbar in 68-90%, and cervical in 65-78% of affected individuals.
• CT and MRI scans are better at detecting associated findings (e.g. ossification of the posterior longitudinal ligament of the cervical spine) and complications (e.g. spinal cord compressive myelomalacia).³

Associated diseases⁴

• DISH often coexists with osteoarthritis.
• Patients with DISH tend to have a greater body mass index, higher serum uric acid levels and are more likely to have diabetes mellitus.

Management

• NSAIDs are prescribed for symptomatic relief.⁵
• Chiropractic manipulation has been used to good effect.³
• Ossification around hip and knee joints may require arthroplastic surgery.⁶

Complications

• Compression of nerve roots may cause myelopathy.
• Overgrowth of ligamentous calcification may rarely impinge on other structures, e.g. the oesophagus.⁷ Dysphagia should be treated conservatively, surgical management being reserved for severe and recalcitrant cases.⁸
• Occasionally osteophytic formation in the cervical vertebrae causes cervical compression symptoms.³
• Thoracic spine osteophytes have on rare occasions been found to compress a bronchus, the larynx and trachea,⁹ and the inferior vena cava.¹⁰
• Reduced vertebral column flexibility predisposes to vertebral fracture.

Prognosis

The prognosis is usually not affected in any adverse way, unless there are complications and associated joint or soft tissue problems.