To evaluate a innovate one stage procedure of the PJI knee treatment using computed assisted guidance. Our objectives; to increase the functional results by optimizing the anatomical joint reconstruction and to verifie if CAS help to simplifie and standardize these complex surgeries It's a prospective, single surgeon study. Since septembre 2011, 41 patients treated for chronic knee PJI in a one stage revision (one of them had a ipsilateral chronic knee arthritis). For all of them, a computed assisted guidance, the ExactechGPS® system was used. This system offers the possibility to define specific profiles to performe primary TKA surgeries. A personnalized profile of revision was created. All surgeries were performed with the same protocole; independently of the type of germ, with no use of tourniquet, no drainage by performing the same debridement procedure step by step and by using the same knee components 27 males, 14 female with 26 PJI of primary TKA, one infected unicompartimental prosthesis and 15 PJI of first revised TKA has been treated. The average age was 71 years old (55–87). The time of surgery was on average 135 mn (120 – 195 mn). The average time of hospitalization was 10 days (7–16). The average follow up was 20,9 months (6–47 months). The ROM were on average 114,7% (90°–130°), None post operative HKA outliers were reported. 3 patients presented a failure of the PJI treatment (one after a local open traumatism, one diabetic patient, one after a early revision for mechanical complication). None specific CAS complications and no failure of the CAS procedures are reported. As surgeon, CAS simplified the management of the bone loss after debridement and the control of the differents parameters (HKA, external femoral rotation, ligamentary balancing, lign joint…) by a real time feedback. we changed our practise by using more constraint condylar component instead hinge prostheses With a rate of success of 92,7% at this follow up, the one stage option appears to be valided. Using CAS is a safe option with no specific complication. It increases the quality of the ROM, a earlier functional recovery and a better middle term clinical result. Both combined, It should be a optimal medicoeconomical solution. compared revision using mechanical ancillary.
