Unexpected varus deformity and concomitant metal ion release and MRI findings of modular-neck hip stems: descriptive RSA study in 75 hips with 8 years' follow-up.

ABSTRACT: Background and purpose - Modular-neck hip stems have been identified with corrosion-related problems from the neck-stem junction. We report an ongoing varus deformity of modular-neck hip stems with simultaneous metal ion release observed during a study comparing the migration of modular vs. standard hip stems.Patients and methods - We followed 50 patients with modular and 25 with standard neck stems using radiostereometry (RSA). At 5-year follow-up, we noted a compromised integrity of the modular stem with varus deformity in the neck-stem interface. Changes in head-tip distance as well as whole-blood ion concentration and MRI findings were analyzed. The modular stems were followed further up to 8 years.Results - The head-tip distance decreased continuously by 0.15 mm per year resulting in

SUBMITTER: Kiernan S 

PROVIDER: S-EPMC7919878 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature