Muscular gastrocnemius spacer: a two stage reimplantation technique for infected total knee arthroplasty.

Aim: We present a two stage reimplantation technique for infected total knee arthroplasty using a muscular gastrocnemious spacer that allows delivery of high local concentrations of antibiotics in absence of heterologous materials associated with high percentage of infection.

Material Of Study: Between January 2009 and June 2011 we selected 8 patients with diagnosis of total knee arthroplasty deep infection. All patients underwent a surgical protocol that consisted of a two stage procedure with harvesting of medial gastrocnemious rotational flap followed by delayed reimplantation of prosthesis. All of them received 6 weeks of tailored intravenous antibiotics suggested by the infectious disease consultant and none had positive cultures at the time of reimplantation.

Results: The outcome was considered excellent for 6 of the 8 knees, good for 1, fair for 1, and poor for 0 joint. The reimplantion procedures were completely successful in all cases and all patients were able to walk again after rehabilitation program.

Discussion: Our surgical protocol guarantees wound healing without presence of disuse osteoporosis nor joint stiffness with scar tissue obliterating joint space. Moreover it shows a lower percentage of reinfection. This is connected to the presence of remaining microbiological organisms at the moment of closure that can develope a biofilm that adheres to biomaterial surfaces, enabling a complete bacterial eradication. The gastrocnemious muscle plays either the role of a natural spacer, either the function of coverage and protection of the new joint articulation after the reimplantation of the new device.

Conclusions: The surgical and medical protocol used in our study resulted in clinical absence of infection in all our patients with lower postoperative complications in relation to the complete eradication of infection.