In the second quarter, we sold nine MAKOplasty hip applications, seven of which were sold with domestic RIO system sales during the quarter and two of which were sold as upgrades to existing commercial systems.
As of June 30, 2012, 71 RIO systems or 58% of our domestic installed base have purchased the MAKOplasty hip application. Worldwide, through the second quarter, our customers performed 2,590 MAKOplasty procedures, of which 2,494 were performed at domestic sites. Of the 2,494 domestic procedures, 281 were hip MAKOplasty procedures.
The 2,590 MAKOplasty procedures performed represents a 13% increase over the procedures performed in the first quarter of 2012 and a 66% increase over the procedures performed in the second quarter of 2011.
The average monthly utilization per system was 7.2 procedures per system, per month during the second quarter of 2012, an increase from 6.6 in the first quarter of 2012 and 6.4 in the second quarter of 2011. Through June 30, 2012, approximately 17,700 procedures have been performed since the first procedure in June of 2006.We had five abstracts accepted to upcoming conferences and attended four conferences in the quarter. At the annual CAOS UK meeting Dr. [Mark Blight] presented data on the first 50 patients in the MAKO sponsored randomized control trial being conducted at the Royal Glasgow Infirmary in conjunction with the University of Strathclyde. The study compared unique compartmental knee implant alignment error between two groups of patients. Those receiving the makeover stores MCK unicompartmental implant delivered by the RIO system and those received the Oxford Partial Knee mobile bearing unicompartmental implant using manual non-robotic instrumentations. The results are statistically significant and indicate more accurate alignment using RIO system. Specifically the tibial internal and external rotation, 70% of the MAKOplasty procedures showed less than a two degree of error against their target value, while only 20% of the Oxford cases were less than two degrees of error. Read the rest of this transcript for free on seekingalpha.com