Current concepts, classification, and results in short stem hip arthroplasty

Area of Science:

• Orthopedic surgery
• Biomedical engineering
• Implant design

Background:

• Short hip stems are increasingly used in hip arthroplasty.
• Current classifications lack standardized definitions for length and bone preservation.
• Variability exists in implant concepts for femoral fixation and length.

Purpose of the Study:

• To analyze and classify short hip stems based on their design and femoral fixation.
• To evaluate the existing literature on short hip stem performance and bone preservation.
• To establish a clearer understanding of short hip stem characteristics.

Main Methods:

• Classification of 15 selected short hip stems into collum, partial collum, trochanter-sparing, and trochanter-harming categories.
• Review of mid-term and short-term clinical data, excluding stems with insufficient data.
• Comparison of implant designs based on available clinical evidence.

Main Results:

• The 15 analyzed stems were categorized: 1 collum, 7 partial collum, 4 trochanter-sparing, and 3 trochanter-harming.
• Mid-term results were available for only 3 partial collum designs.
• Short-term studies showed femoral revision rates below 1 per 100 component years for most total hip arthroplasties.

Conclusions:

• A simple length limit cannot define short hip stems.
• Some short hip stem designs offer survivorship comparable to traditional stems.
• Bone preservation for future revisions is achievable with certain short hip stem designs.