Paget's disease and back pain

Paget's disease is a rare cause of back pain, often diagnosed with unconstrained radiography performed for other purposes or when the patient finds a swelling of long bones. At an early stage of the disease, bone resorption occurs, and the affected areas are vascularized. After resorption, a new peget bone is formed, which is deposited compactly and unstructurally. The process of resorption and bone formation is very active, the rate of bone tissue renewal is increased by 20 times compared with the norm. This process leads to the formation of a characteristic structure in contrastless radiography, which includes areas of bone resorption, called the limited osteoporosis. The areas of formation of the new bone represent a non-uniformly expanded cortex and a compact substance, a grooved pattern with sensory regions of various densities, which reflects the chaotic nature of the formation of a new bone.

The prevalence of Paget's disease is approximately 2%, is rare in India, Japan, the Middle East and Scandinavia. Although most patients with Paget's disease do not have any symptoms, and their disease is an accidental finding in radiography on another occasion, they can often be troubled by back pain. It is suggested that the etiology of back pain in Paget's disease is multifactorial. Pain can be caused by the process of resorption, as such, and deformation of the facet joints by the formation of a new bone. Both these processes change the functional stability of the spine and enhance the existing arthropathy of the facet joints.

Patients with Paget's disease may also experience thickening and widening of long bones and an increase in the skull due to the formation of a new bone. In rare cases, excessive bone growth on the base of the skull can cause compression of the brainstem with catastrophic consequences. There may be a secondary hearing loss due to compression of the eighth pair of cranial nerves with a newly formed bone tissue or direct involvement of small ossicles into the pathological process. Sometimes excessive formation of bone tissue in the spine can cause compression of the spinal cord, which in the absence of treatment can lead to paraplegia. Pathological fractures due to excessive resorption of the vertebrae can cause severe pain in the back. There may also be secondary pain in the thigh due to calculating periarthritis. Often there are kidney stones and gout, especially in men with Paget's disease. Less than 1% of bone damage can turn into malignant osteosarcoma.

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Symptoms of Paget's Disease

Despite the fact that the disease is asymptomatic, pain is a frequent complaint, which ultimately leads the doctor to diagnose Paget's disease. The seemingly minor trauma can lead to pathological compression fractures of the vertebrae. Pain when moving in damaged bones is often detected during physical examination, as well as excessive bone growth - when palpation of the skull or other affected bones. There may be neurological signs due to secondary nerve compression due to excessive bone growth and pathological fractures. Pain in movement in the peripheral joints, especially in the hip due to calcified periarthritis, is a frequent finding in patients with Paget's disease. Also pay attention to hearing loss.

Examination

As mentioned above, Paget's disease is often diagnosed diarrheally when the patient undergoes a radiological examination for a completely different cause, for example, intravenous pyelography due to kidney stones. The classical radiographic picture of the areas of bone resorption with the surrounding dense zones, chaotic bone structure indicate the diagnosis of Paget's disease. In patients with Paget's disease, radionuclide scanning of the bone can be used to determine the extent of the lesion, since not all bone lesions appear clinically. MRI is indicated to all patients with suspected Paget's disease who have signs of spinal cord compression. A study of serum creatinine and a biochemical blood test, including serum calcium, is shown to all patients with Paget's disease. The level of alkaline phosphatase increases, especially during the resorptive phase. Given the increased occurrence of hearing loss in patients with Paget's disease, he is shown an audiometric study.

Differential diagnosis

Many other bone disorders, including osteoporosis, myeloma, osteopetrosis, primary and metastatic bone tumors, can mimic the clinical manifestations of Paget's disease. Acromegaly is also a common clinical symptom. Metastatic tumors of the prostate or breast can cause pathological fractures of the spine and ribs and metastases in the skull bones, which can be mistaken for Paget's disease.

Treatment of Paget's disease

Many patients with asymptomatic Paget's disease require only psychological support. Treatment of pain associated with Paget's disease should start with acetaminophen, NSAIDs. It may be necessary to add narcotic analgesics in case of severe pain associated with pathological fractures. Orthopedic devices, such as Kesh's corset and rib bandage, help stabilize the spine and ribs, and should be used for pathological fractures. Local thermal and cold applications can also be useful. Repeated movements that cause the syndrome should be avoided. Patients who do not respond to this treatment are shown injections of affected areas with local anesthetics and steroids in the form of intercostal and epidural blockades. In special cases, spinal administration of narcotic analgesics may be effective

In patients who did not respond to this treatment, calcitonin and zolendronate were used with some success. In rare cases, excessive bone destruction may require cytostatic drugs, such as dactinomycin. Efficacy in symptomatic terms of pulse therapy with high doses of steroids was also shown.

Side effects and complications

Primary complications in Paget's disease are associated with the phases of resorption and the formation of bone tissue. Excess bone resorption can lead to compression fractures of the vertebrae, fracture of the ribs and occasional fractures of long bones. Excessive formation of bone tissue leads to compression of neural structures, which can cause a decrease in hearing, myelopathy and paraplegia. With increased frequency, kidney stones and gout are observed, especially in men with Paget's disease. In rare cases, the formation of a new bone is so great that it causes secondary hypersystolic heart failure due to increased blood flow. As mentioned above, malignancy of the affected bone tissue occurs in approximately 1% of patients with Paget's disease.

A thorough examination of patients suffering from Paget's disease is necessary to prevent possible complications of the disease. The clinician should pay attention to mild signs of compression of the brain stem and spinal cord. Epidural and intercostal injections of local anesthetics and steroids can provide a good temporary relief of the pain associated with Paget's disease, which could not be stopped by pharmacotherapy.