Do new trainees pose a threat to the functional outcome of total knee arthroplasty? – The ‘January/July’ effect in a developing South Asian country: A retrospective cohort study

Introduction Previous studies have shown that the introduction of new trainees/residents results in an increased morbidity and mortality for the hospital. With differences in induction times of residents across the world and majority of research coming from the US, we aim at studying whether the introduction of new orthopedic residents/trainees bode ill for patients undergoing a total knee arthroplasty (TKA) in a developing country. Materials & Methods Single center retrospective cohort study done from 2006 to 2015. Induction of new residents in Pakistan happens at the start of the year (January). A total of 673 patients who underwent a unilateral or bilateral TKA where included in study. Surgeries were divided into 4 quarters of the year and comparison was carried out between them. Binomial logistic regression analysis was also carried out for significant variables. Results Surgeries done during the first quarter (Jan–March) was not associated with a longer length of stay (LOS) [p = 0.651], a longer total operative time (TOT)[p = 0.471], a higher drop in hemoglobin (Hb)[p = 0.146] and postoperative complications. Surgeries done during the first quarter of the year are a significant independent predictor of postoperative cardiac complications [p = 0.02]. Conclusion Based on our study, we found no evidence to support a hypothesis of new trainees/residents bringing about an increased intraoperative and postoperative morbidity. Further large multicenter database studies are required from the South Asian region to further study this effect.