Failure Causes in Total Hip Replacements: A Review

Abstract

There are many different materials, shapes, and sizes of hip implants that surgeons should research to decide which is best for each patient. There have been advances in these prostheses in the previous 30 years that allow for the most positive result. Studies have been completed by physicians and research scientists to assist in educating the medical community regarding new advancements in the subject of hip replacements. This paper will discuss these advances and the factors affecting the success rate of hip implants. Some of these include smoking, obesity, metal allergy, corrosion, and medications. Each failure mode has previous research completed to expand upon the underlying causes and what could be done differently to ensure a more positive outcome. This research also discusses the successful aspects of the implants that should become more commonplace for total hip arthroplasties. A recurring failure was due to metal allergy caused by metal particles entering the body. Patient factors also have an influence on the lifespan of the implants. Older patients generally have a lowered bone density which can lead to the implant becoming loose inside the bone. The implant shape and orientation can affect the prosthesis success as well. Studies found that larger head size and a more vertical component angle led to a greater failure rate. This could be due to greater frequency of dislocations due to improper size and orientation for the specific patient.