Abstract
Introduction
Adverse Local Tissue Reactions (ALTR) have been reported in association with both wear and corrosion. Tissue reactions have been reported in association with corrosion at CoCr head-CoCr neck, CoCr head-TiAl6V4 neck, and CoCr modular neck on beta-titanium (TMZF) stem junctions. The current abstract reports on 3 cases of ALTR in association with CoCr modular necks on convention titanium (TiAl6V4) stem junctions.
Case 1. A 67 year old male (87 kg, 1.73 m, BMI 29.1) presented with new onset hip irritation 11 months after surgery. Radiographs show no abnormalities. Further investigation revealed the following: ESR = 95, CRP = 5, Cr level = 1.0, Co level = 4.1, leukocyte transformation testing = highly reactive to nickel. Hip aspiration was culture negative with 11,250 wbc. Metal artifact reduction MR showed cystic local reaction in the region of the greater trochanter.
Case 2. A 52 year old male (89 kg, 1.83 m, BMI 26.5) presented with new onset hip irritation 30 months after surgery. Radiographs show no abnormalities. Further investigation revealed the following: ESR = 7, CRP = 5.4, Cr level = 2.1, Co level = 4.8, leukocyte transformation testing = reactive to nickel. Hip aspiration was culture negative with 3995 wbc. Metal artifact reduction MR showed cystic local reaction in the region of the iliopsoas.
Case 3. A 52 year old male (104 kg, 1.85 m, BMI 30.1) presented with new onset hip irritation 26 months after surgery. Radiographs show no abnormalities. Further investigation revealed the following: ESR = 33, CRP = 34.9, Cr level = 1.0, Co level = 3.7, leukocyte transformation testing = no reactivity to any of the biomaterials. Hip aspiration was culture negative with 3,780 wbc. Metal artifact reduction MR showed cystic local reaction in the region of the iliopsoas.
Discussion
All three of these patients are scheduled for revision surgery. All three had ceramic-ceramic bearings. We have experience with 1029 ceramic-ceramic THA with fixed neck conventional titanium and modular titanium neck implants with minimum 2 yr f/u and have never diagnosed an adverse reaction in any of these patients. It is possible that corrosion at the CoCr neck on TiAl6V4 stem junction is the root cause of these reactions. Although the incidence of diagnosed reactions is roughly 1%, it appears that the use of CoCr at any junction under significant mechanical stress can result in adverse local tissue reaction and therefore should either be avoided or used with great caution and compelling indications.
