Various designs of cement restrictors for total hip arthroplasty have shown a variability in resistance to intramedullary pressure and migration. The performance of a conical bone plug was studied in 275 cemented total hip arthroplasties with a followup between 5 and 19 years. In a radiographic analysis the relation between the plug position and the cement mantle quality was investigated. The results were compared to the performance of other cement restrictors as reported in the literature. Good to excellent cement mantles were observed in 80% of the femurs. A significant correlation between the stability of the plug and the quality of the cement mantle was found. Forty-nine percent of the plugs were within 1 to 3 centimetres of the Exeter stem hollow centraliser. We also demonstrated that bone plugs performed almost always better than polyethylene or gelatine restrictors reported in other studies.