ANTIBIOTIC LOADED SPACER FOR TWO – STAGE REVISION OF INFECTED TOTAL HIP REPLACEMENTS

Abstract

Objective of study: Two-stage revision procedure of infected total hip replacements usually involves the application of a temporary antibiotic-loaded poly-methylmethacrylate spacer. A preformed spacer which allows weightbearing and joint motion while ensuring a sustained antibiotic release was evaluated.

Material and Methods: 26 consecutive patients affected with an infected total hip arthroplasty were treated by the insertion of an industrially preformed temporary spacer (Spacer-G). This device comprises a cylindrical stainless-steel rod coated with bone cement supplemented with gentamicin (1.8% w/w) and vancomycin (2.5% w/w). Joint mobilization and assisted weight-bearing were permitted when bone stock allowed an adequate mechanical stability of the spacer. Reimplantation was performed when normalization of serological parameters was obtained. Patients’ evaluation included clinical assessment, standard x-ray and laboratory parameters.

Results: The spacer remained in situ for an average of 155 (70-272) days allowing healing of the infection in 24 cases. 5 patients required resection-arthroplasty (2 persistent infections, 2 inadequate local bone conditions, 1 acute recurrence of infection). In 4 cases the spacer dislocated, because the head diameter was too small. The successfully-reimplanted patients (21) were assessed with a mean 48 (17–83) months follow-up showing no clinical or biohumoral signs of infection recurrence. Functional outcome was satisfactory (mean value of Harris Hip Score: 79) and no radiographic aspects of loosening were observed.

Conclusions: The Spacer-G used in the two-stage revision of infected total hip replacements permitted an effective local antibiotic release together with some range of joint motion, which improved the quality of life of the patients during treatment of infection and accelerated recovery of function after reimplantation.