AMISTEM H FEMORAL STEMS

Additional Manufacturer Narrative

BATCH REVIEW PERFORMED ON 15 JUNE 2026 STEM: AMISTEM H 01.18.131 AMISTEM-H STD. SIZE 1 (K093944) LOT 164598: (B)(4) ITEMS MANUFACTURED AND RELEASED ON 31-OCT-2016. EXPIRATION DATE: 18-OCT-2021. NO ANOMALIES FOUND RELATED TO THE PROBLEM. TO DATE, (B)(4) ITEMS OF THE SAME LOT HAVE BEEN SOLD WITH NO SIMILAR REPORTED EVENT DURING THE PERIOD OF REVIEW. CLINICAL EVALUATION 9 YEARS AFTER PRIMARY CEMENTLESS THA, THE STEM IS MOBILIZED AND NEEDS REPLACEMENT. THE XRAY SHOWS THAT THE STEM HAS BECOME QUITE SMALL, WHICH MAY ALSO MEAN THAT THE FEMALE PATIENT UNDERWENT BONE MODIFICATION OVER THE YEARS. THE SURGEON DECIDED ALSO TO REPOSITION THE CUP THAT IS SHOWN TO BE RATHER PROTRUDING FROM THE ACETABULUM. THIS SHOULD BE CATEGORIZED AS A CASE OF IDIOPATHIC ASEPTIC LOOSENING FOR THE STEM AND REPOSITION SURGERY FOR THE CUP. ROOT CAUSE: BASED ON THE INFORMATION AVAILABLE, NO DEFINITIVE ROOT CAUSE CAN BE ESTABLISHED FOR THE STEM MOBILIZATION. THE EVENT MAY HAVE BEEN INFLUENCED BY PATIENT-SPECIFIC BONE REMODELING OVER TIME. REGARDING THE ACETABULAR COMPONENTS, THE REVISION APPEARS TO BE RELATED TO THE SURGEON¿S DECISION TO REPOSITION THE CUP DUE TO ITS PROTRUDING POSITION, WITH NO INDICATION OF A DEVICE-RELATED ROOT CAUSE.

Description of Event or Problem

AT ABOUT 9 YEARS AND 4 MONTHS FROM THE PRIMARY, THE PATIENT CAME IN PRESENTING PAIN AND INSTABILITY DUE TO A LOOSE STEM AND THE CAUSE IS UNKNOWN. THERE WERE NO INDICATIONS OF TRAUMA. THE SURGEON OBSERVED THAT THE CUP POSITION WAS NOT TO HIS PREFERENCE. THE SURGEON REVISED THE VERSAFITCUP CC 50 MM CUP TO A MPACT D 56 TWO-HOLE CUP, REVISED THE 36 MM COCR HEAD TO A 36 MM BIOLOX HEAD L, REVISED THE VERSAFITCUP CC TRIO 36/E LINER TO A D 36/F HOODED PE LINER, AND REVISED THE AMISTEM H STANDARD SIZE 1 STEM TO A M-VIZION D 16 MM L 140 MM STRAIGHT STEM. THE SURGERY WAS COMPLETED SUCCESSFULLY.