Abstract
The management of infected total hip replacements is a challenging problem in orthopaedic surgery. Two-stage revision procedures usually involve the application of a temporary antibiotic-loaded polymethylmethacrylate spacer. A preformed spacer which allows weight-bearing and joint motion while ensuring a sustained antibiotic release was evaluated.
From September 1996 to March 2002, 26 consecutive patients 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 (1.9% w/w) and vancomycin (2.5% w/w). The spacer is currently available in three sizes of head diameter, each size with two stem lengths. Joint mobilisation and assisted weight-bearing were permitted when the bone stock provided adequate mechanical stability of the spacer. Patients’ evaluation included clinical assessment and standard X-ray and laboratory parameters. Reimplantation was performed when serological parameters had normalised.
The spacer remained in situ for an average of 155 (70–272) days, allowing healing of the infection in 24 cases. Five patients required resection arthroplasty (two persistent infections, two inadequate local bone conditions and one acute recurrence of infection). A second spacer was implanted after 4 months in one subject. In four cases the spacer dislocated, because the head diameter was too small or because of a rotational instability of the stem in the femur. The successfully-reimplanted patients (21) were assessed with a mean 53 (22–88) months of follow-up, showing no clinical or bio-humoral signs of infection recurrence. Functional outcome was satisfactory with a mean value of Harris Hip Score of 79 (53–100), and no radiographic aspects of loosening were observed.
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.
