Chapter 33, Problem 17STP

Summary Introduction

To write:

About the reason for the replacement of knee or hip joints inolder patients more frequently as compared to younger patients.

Introduction:

A joint is a region where two or more bines arearticulated. Joints are majorly classified based on the tissue thatconnects the two bones. The hip joint is a type of synovial joint at which the femurhead and pelvic acetabulum are articulated. The knee joint is another type ofsynovial joint at which the tibia, femur, and patella are articulated.

Explanation of Solution

The hip joint is a type of ball and socket joint while the kneejoint is a type of hinge joint. Both types of joints are under vigorousstress, especially in young individuals. These joints are continuously activeand thus this poses a major challenge in their replacement.

During the replacement of the knee and hip joints, old damaged parts are removed and artificial parts are added at their place. The major drawback of the artificial parts is that these parts are not identical to the original ones and are generally smaller. The small size helps in easy articulation during the replacement surgery.

Now being small, these artificial parts are not completely blocked at the site of the joint and there are chances of displacement of these artificial parts during vigorous stress or strenuous activities.

Therefore, hip and knee replacement surgery are generally performed in older or less active patients to avoid the displacement of the artificial part.

Conclusion

Young patients are more active and perform vigorous activitiesas compared to older or less active patients. Now because artificial partsused in the knee or hip replacement surgery are smaller than the original ones,they may get easily displaced. Therefore, to avoid the displacement of theartificial parts, the procedure is performed only in less active or old patients.