SEMEN METAL ION LEVELS AND SPERM QUALITY IN PATIENTS WITH METAL ON METAL TOTAL HIP REPLACEMENT

Abstract

Introduction: Several studies have shown the presence of cobalt (Co) and chromium (Cr) ions in blood, urine, and organs of patients after THA using Co-Cr alloy-based implants. Even though it is well known that exposure to heavy metals may lead to significant alterations in human sperm morphology and motility, less is known on the effect of Co and Cr on semen parameters after metal on metal (MOM) hip replacement.

Methods: Semen was collected form 10 patients between 41 and 49 years old (mean=45.9±3.0 years) by masturbation after 2–3 days of abstinence. The time of implantation varied from 1 to 9 years (mean=5.1±3.9 years). Samples were collected in a sterile container and examined within 1h after ejaculation for morphology, motility, and number of sperm cells following standard criteria. All patients were doing well at their follow-up visits (Harris Hip Score=94±4; UCLA activity a score=7±1) and no sign of osteolysis was observed on X-rays.

Co and Cr concentrations were measured in both the seminal plasma and in the blood of patients by inductively coupled plasma-mass spectroscopy (ICP-MS).

Results: results showed that the levels of Co in the seminal plasma and the blood of the patients were not statistically different. However, the level of Cr was significantly lower in the seminal plasma than in the blood of the patients. The ejaculate volume (2.1 ±0.6 ml), the sperm density (66±53 x 106), the total sperm count (151±75 x 106/ml), the pH (8), and the percentage of normal morphology (46±18%) were in the range of the WHO criteria for fertile population and also in the range of reference patients in the city of measurements. However, the viability was lower than that observed in a fertile population without prosthesis (41±19%).

Conclusions: results of the present study strongly suggest that both Co and Cr ions crossover to the semen but that their concentrations were too low to significantly affect sperm parameters of young patients with MM prosthesis. Further longitudinal studies are however necessary to conclusively determine the effect of metal ions from MM prosthesis on sperm parameters.