Description: Segment 1 Ali talks to camera and describes the scope of the lecture. He explains how osteoarthritis is often misdiagnosed as being due to 'wear and tear' of the bones and gives examples as to why this is not true. He explains the clinical reasons for a diagnosis of osteoarthritis in a patient and describes what a clinician should look for in X-ray studies when making this diagnosis. He then differentiates between primary and secondary osteoarthritis: primary is idiopathic with no antecedent cause whereas secondary has an antecedent cause such as a congenital dislocation of the hip or any kind of bone disease. Time start: 00:00:00:00 Time end: 00:05:10:14 Length: 00:05:10:14 Segment 2 Ali refers to a diagram of a knee joint in order to illustrate two theories of what leads to osteoarthritis. He refers specifically to cartilage, comparing its wear and tear to that of the wear and tear of rubber on a car tyre. He then introduces Dr Byers to talk in more detail about microscopic studies of normal and osteoarthritic tissues. Time start: 00:05:10:14 Time end: 00:10:39:17 Length: 00:05:29:03 Segment 3 Byers talks to camera and describes how one searches for indications of osteoarthritic tissues in a patient. Referring to slides and diagrams of femoral head specimens he explains what looks different in the cartilage tissues of these diseased joints. Time start: 00:10:39:17 Time end: 00:14:57:00 Length: 00:04:17:08 Segment 4 Byers continues to discuss the nature of diseased tissues in the femoral head. He shows a series of photomicrographs detailing the very fine details of cartilage surface. He then refers to a graph which shows the distribution over four key areas of damaged cartilage. Byers moves on to discuss osteoarthritis affecting a hip joint. He differentiates between limited and progressive osteoarthritis. Time start: 00:14:57:00 Time end: 00:20:27:18 Length: 00:05:30:18 Segment 6 Ali continues to discuss the electron micrographs of damaged cartilage. He looks more and more deeply into the cellular structure of cartilage. He uses slides of water tanks to demonstrate different inlets and outlets which can be applied to an understanding of the chemistry changes in cartilage tissue during osteoarthritis. Time start: 00:24:58:11 Time end: 00:30:10:16 Length: 00:05:12:05. Segment 7 Ali describes how cartilage change is brought about largely by enzymes activated by hormones and other metabolites dependent on the cellular activity of the tissue. He refers to a photomicrograph of a rabbit joint which has been injected with papain, an enzyme designed to trigger osteoarthritis. Time start: 00:30:10:16 Time end: 00:35:34:00 Length: 00:05:23:09. Segment 8 Ali shows an example of cartilage tissue which is pre-osteoarthritic in which the earliest osteoarthritic changes can be detected. He refers to graphs measuring the levels of various enzymes in the pre-osteoarthritic tissue. Then, through a series of slides, Ali details the sequential changes in tissue during the development of osteoarthritis. Time start: 00:35:34:00 Time end: 00:40:10:00 Length: 00:04:36:00. Segment 9 Ali continues to go through the changes, step by step, in cartilage tissue as osteoarthritis develops, using slides to illustrate each stage. He then concludes the lecture by discussing what kind of treatments might be available for sufferers of osteoarthritis in the future. Time start: 00:40:10:00 Time end: 00:45:09:03 Length: 00:04:59:03