Outsourcing elective surgery has become increasingly commonplace to meet increasing demand from a growing & aging population. There is concern that outsourcing was influencing the nature of residual workload that was unsuitable for treatment elsewhere. This led to the impression that our unit is operating on more complex patients orthopaedic problems, ASA and Body Mass Index (BMI). By losing a disproportionate number of straightforward patients our department's outcomes, productivity and training opportunities could be adversely affected.

Retrospective analysis of prospectively collected data of primary hip / knee arthroplasties between July & December for 2014(pre-outsourcing), 2015 and 2016(post-outsourcing). ANOVA, Tukey Honest Significant Difference(HSD) and Pearson's correlation used.

Total of 726 primary arthroplasties were performed with an almost 50 % reduction post outsourcing. Post-outsourcing, BMI and ASA were significantly worse with a ANOVA of p=0.001 and HSD p=0.003. Length of stay increased from 5.4 days in 2014 to 6.2 days in 2015 ANOVA p< 0.001 but decreased in 2016. BMI significantly affected operating time (Pearson's r =0.12, p< 0.05) and anaesthetic time (Pearson's r =0.19, p< 0.05). ASA significantly affected length of hospital stay, p< 0.01 and operation time, p=0.007 but no effect on anaesthetic time.

In conclusion, we are operating on more complex patients due to current outsourcing setup. Implications for short-term were on anaesthetic and operation time, inpatient stay and training opportunity were affected, with possible long-term implications on individual surgeon and unit outcomes (complications, patient satisfaction).