Degenerative Conditions 8a Flashcards
What are the two broad categories of degenerative conditions discussed in the lecture notes?
The two categories of degenerative conditions discussed are those affecting articular cartilage, primarily leading to osteoarthritis, and those affecting tissues primarily made of collagen, such as tendons, joint capsules, and intervertebral discs.
Describe the progression of articular cartilage degeneration in osteoarthritis (OA).
In osteoarthritis, the articular cartilage becomes split, fissured, and softened. It gradually resorbs, sometimes down to the underlying bone, leading to changes such as thickening and hardening of the subchondral bone and the formation of osteophytes.
What are the two primary theories for the pathology of OA, and how are they potentially interconnected?
The two main theories are that changes may be primarily biochemical or mechanical. These are thought to be interconnected, with mechanical changes potentially leading to biochemical alterations, and vice versa.
Explain the role of metalloproteinases and TIMPs in the biochemical pathology of OA.
Metalloproteinases are enzymes that break down collagen in the cartilage matrix, while TIMPs are compounds that regulate these enzymes. A disruption in the balance between these two compounds is theorised to contribute to the cartilage breakdown seen in OA.
How do mechanical factors contribute to cartilage breakdown in OA?
Mechanical factors, such as fatigue failure due to defective lubrication or abrasive wear from incongruities in the joint, can disrupt the collagen and allow the proteoglycan matrix to leak out.
Differentiate between primary and secondary osteoarthritis.
Primary osteoarthritis has no known underlying cause, whereas secondary osteoarthritis is caused by a known factor, such as a fracture, joint infection, or congenital abnormality.
List three common clinical features of osteoarthritis.
Common clinical features of osteoarthritis include pain, slowly increasing in severity and exacerbated by exercise, stiffness, often more apparent after rest, and swelling of the joint.
What are three radiological signs used to diagnose osteoarthritis?
Three radiological signs of osteoarthritis include narrowing of the joint space, osteophyte formation around the edges of the joint, and sclerosis in the subchondral bone.
Describe the process of collagen disorganisation and subsequent changes seen in tendinopathy.
In tendinopathy, the collagen within the tendons becomes disorganised, leading to splitting (tendinosis), inflammation (tendinitis), and subsequent healing. The tendon can become enlarged and lose elasticity.
What is the underlying cause of a ganglion and what are some of its common locations?
A ganglion is believed to arise from a protrusion of synovial fluid through a microscopic split in a capsule or fibrous sheath. They are commonly located on the dorsum of the hand and wrist and around the ankle.
