Osteoarthrosis (Osteoarthritis): Health Significance, Etiology, Pathology, Clinical Presentations And Management
A General Overview
Osteoarthrosis is predominantly a disease of the elderly but no age is immune to it. It is caused mainly by wear and tear of the joints. It may be primary or secondary. Presence or absence of Heberden’s nodes on the distal interphalangeal joints helps in distinguishing two forms of primary osteoarthrosis- the nodal and non-nodal types.
Etiology: Hereditary factors, overuse of a joint, aging and change in the chemical characteristics of the ground substance have been associated with this disease. Causes of secondary osteoarthritis include pre-existing joint disease, obesity, hypermobility, orthropedic deformities, endocrine disorders like diabetes mellitus, acromegaly and hyperparathyroidism, and sensory neuropathies which impair joint sensations.
Pathogenesis and Pathology: Due to mechanical stress, the collagen is disrupted. This leads to alteration in the composition of the ground substance with resultant loss of resilience. The chondrocyte function and number change. Wear and tear leads to further disruption of collagen fibers. The lubricating mechanism of the joint is impaired. The normal surface matrix is lost, resulting in exposure and fibrillation of the cartilage fibers and later cleft formation. Synovial fluid gains access to the deeper layers of the cartilage. This leads to further destruction of load-bearing cartilage. The cartilage undergoes calcification. The exposed weight- bearing bones undergo eburnation. Osteophytes grow at the margins of articular bones. Still later, subchondral bone may fracture to form cysts. Though, synovial inflammation and effusion may occur, these processes are generally mild.
The Painless Herbeden Nodules
Many cases are symptomatic though abnormalities are detectable radiologically. Knees, cervical spine, lumbar spine, hips, shoulder and distal interphalangeal joints are affected most frequently. Osteophyte formation at the distal interphalangeal joints leads to the formation of painless Heberden’s nodes. In the knees movement of the patella, sidewards causes pain. Vague pain and stiffness in the knew especially after getting up from the sitting posture are the early symptoms. The patients experience disability while walking down the stairs or slopes. The quadriceps undergoes atrophy. Transient effusions may occur even in asymptomatic cases. Osteophytes may be elicited on movement. Osteoarthritis of the cervical spine leads to a group of clinical manifestations and are described under cervical spondylosis. Affection of the lumbar spine leads to low backache and sciatica.
Radiology: The bones show subchondrial sclerosis, narrowing of joint spaces, osteophyte formation, joint destruction, cyst formation in the cortical bone and loose bodies (joint mice) within the joints.
Course And Prognosis: Osteoarthritis is a slowly progressive disease which leads to considerable morbidity with passage of time.
Management: The principles of management include prevention of overuse of the affected joint, limitation of activity to reduce pain, and physiotherapy to strengthen the muscles. Application of heat and graded movements help in reducing pain.
Medical treatment is asymptomatic. Non-steroidal anti-inflammatory drugs relieve pain and inflammation. Reduction of weight and management of metabolic and endocrine disorders may serve to arrest the progress of the joint lesions. Corrective surgery is indicated in intractable cases not responding to medical treatment.
© 2014 Funom Theophilus Makama