Slovenská chirurgia 1/2022

Mechanical failure of modular femoral stem in total hip arthroplasty

Total hip arthroplasty with modular primary implants provides possibility of peroperative decision and chosen implant can be customised to local anatomical conditions. Their popularity were growing mostly in the last two decades, when besides their utilization in revision systems it began to use them in primary hip arthroplasty more commonly. There is controversal opinion for this use of them today. Majority of departments using modular components in primary hip arthropalsty indicates them in case of altered local anatomical situation. Especially in cases of postdysplastic configuration changes. But there are departments, where they are indicated anad used for operation of all patients. Quality of material is in this kind of implants more important than in monolitic. There is necessity of correct material combination for neck and stem, good implant design and precisious manufacturing. Due this severe demands to manufacturing it was several implants withdrawn of market. It was due neck or stem failure but in some cases due to abrasion and corrosion in connection between neck and stem. In the situation of high-grade implant quality are describing good results. It is for both cemented and uncemented. We have been using three kinds of implants at our department in the last twenty years. Our experiences are quite good globally. But in the case of one implant – AnaNova/AnaNova M II we observed during the long time period more frequent occurrance of implant failure – neck or stem fracture in the region of connection between neck and stem. In our paper we report five cases of implant failure.

Keywords: total hip arthroplasty, modular implants, complications, failure of modular implant