Question

1) What is the major concern with ceramic on ceramic joints?    2)What is the major issue with hard on soft joints?What is the adverse clinical result that has been reported associated with this issue? Describe pathological mechanism. 3) What is the major concern with metal on metal joints list 3 consequences what are anticipated?

Answer 1

1) What is the major concern with ceramic on ceramic joints?

Squeaking or noise is the major concern with ceramic on ceramic joints. Ceramic is a hard material, in this type hard (ceramic) is using on hard (ceramic). If we place hard on hard, the major concern will be the noise generation (when moving/sliding over each other). So noise can be observed while sitting, standing, bending, and walking. Another concern is fracture of ceramic joint. Generally these joints are placed with good compression strength ceramic. But, if the stress on joint is more than the compression strength the joint will be fractured.

2) What is the major issue with hard on soft joints? What is the adverse clinical result that has been reported associated with this issue? Describe pathological mechanism.

In this type hard metal or ceramic (head of joint) is placed on soft material like polyethylene (socket of joint/acetabulum) and this polyethylene material is placed on metal surface of acetabulum. Means plastic/polyethylene is placed between two metal/ceramic surfaces. Wear of polyethylene (plastic) surface is the major concern. Polyethylene particles are recognized as foreign material by the tissue which surrounds it, and tissue hypersensitivity reactions will start, this causes aseptic loosening, which leads to osteolysis. Sliding with hard material leads for wearing of Plastic surface. Apart from this the proteins of synovial fluid will increase the wear rate of polyethylene. The plastic particles

3) What is the major concern with metal on metal joints list 3 consequences what are anticipated?

The major concern with metal on metal joint is wearing of metal particles. During walking the metal ball will slide over metal socket. So metal surface will be rubbed, which leads to wearing of metal. Due to this metal particles will be released. These metal particles will produce hypersensitivity reactions, which leads to joint inflammation. The tissues adherent to joint will get damaged, this causes pain. These metal particles will also enter the blood stream and reaches different organs like brain, kidneys, heart, etc. Another concern is same like ceramic on ceramic joint, i.e., noise generation.

list 3 consequences what are anticipated:

1. Hypersensitivity reactions and soft tissue damage

2. Impairment of kidney function

3. Heart problems like cardiomyopathy

4. Impairment of neurological mechanisms, like impairment of vision