The Role of Subchondral Sclerosis in Osteoarthritis

Subchondral sclerosis is one of the myriad complications of osteoarthritis. Simply put, subchondral sclerosis is the hardening and/or thickening of the layer of bone that is directly under the cartilage in joints. This is identified through X-rays or other imaging diagnosis along with tests for the layer of cartilage thinning. On an X-ray, subchondral sclerosis will appear as an area of bone within the joint that is whiter than the rest of the bone.

What Osteoarthritis Does to Joints

Osteoarthritis is the most common cause of arthritis, and is potentially crippling if left untreated. Over time, the cartilage in joints wears down from excessive stress and, often, repetition. The result is painful joints that are frequently red and inflamed as the cartilage wears thin. In advanced cases, there may not be any cartilage left and bone can be grinding against bone.

Causes of Subchondral Sclerosis in Osteoarthritis

Osteosclerosis (hardening of the bone) happens for a number of reasons, including trauma. In the case of subchondral sclerosis as it relates to osteoarthritis, it is the result of trauma done to the joints. There are a couple of different ways that subchondral sclerosis can occur, namely through compaction or abnormal osteoblastic activity.

In lay terms – the stress put on the joints can actually compress the bone on either side of the joint. The inflammation that occurs in the joints can also increase blood supply to the joint, encouraging cells that create new bone (osteoblasts) to form and/or increase activity. This does not mean that the cells responsible for removing old bone (osteoclasts) increase their activity. In terms of osteoarthritis, either or both of these processes may be contributing to subchondral sclerosis.

Implications of Subchondral Sclerosis

While osteoarthritis is extremely damaging to the joints in and of itself, complications such as subchondral sclerosis come with their own set of problems. Bone that is denser – especially if the density is made up of old or dead cells – is much more brittle and likely to fracture. In addition, without the normal bone matrix in place, the areas affected by the subchondral sclerosis are much more vulnerable to impact damage because there is none of the flexibility and “give” existent in a normal bone.

How to Slow Osteoarthritis

Unlike most other types of arthritis, osteoarthritis is believed to be primarily the result of wear-and-tear on the joints, or the result of injuries from accidents or high-impact sports. Once the joints are damaged there is little that can be done for them, but there are plenty of options for minimizing the damage done to your joints.

The most damaging element on the joints is excessive weight. Studies show that every pound of weight over a normal healthy weight puts the equivalent of four pounds of extra stress on the joints with every single step. In other words, just 10 pounds overweight is putting wear and tear on your knees to the tune of 40 pounds per step. A healthy diet is essential to achieving and maintaining your ideal weight, and sufficient water intake is critical to tissue health. Your doctor may also be able to recommend minor changes in the way you move that can significantly reduce the stress on major joints. Proper osteoarthritis-friendly exercise has always been deemed important, but recent data shows that it is absolutely essential in the management of osteoarthritis. Osteoarthritis is extremely common with age, but it doesn’t have to significantly impact activity levels with the proper management.