Analysis of the relationship between surgeon procedure volume and complications after total knee arthroplasty using a propensity-matched cohort study

Abstract

ObjectivesThis study aimed to identify a threshold in annual surgeon volume associated with increased risk of revision (for any cause) and deep infection requiring surgery following primary elective total knee arthroplasty (TKA).DesignA propensity score matched cohort study.SettingOntario, Canada.Participants169 713 persons who received a primary TKA between 2002 and 2016, with 3-year postoperative follow-up.Main outcome measuresRevision arthroplasty (for any cause), and the occurrence of deep surgical infection requiring surgery.ResultsBased on restricted cubic spline analysis, the threshold for increased probability of revision and deep infection requiring surgery was <70 cases/year. After matching of 51 658 TKA recipients from surgeons performing <70 cases/year to TKA recipients from surgeons with greater than 70 cases/year, patients in the former group had a higher rate of revision (for any cause, 2.23% (95% Confidence Interval (CI) 1.39 to 3.07) vs 1.70% (95% CI 0.85 to 2.55); Hazard Ratio (HR) 1.33, 95% CI 1.21 to 1.47, p<0.0001) and deep infection requiring surgery (1.29% (95% CI 0.44 to 2.14) vs 1.09% (95% CI 0.24 to 1.94); HR 1.33, 95% CI 1.17 to 1.51, p<0.0001).ConclusionsFor primary TKA recipients, cases performed by surgeons who had performed fewer than 70 TKAs in the year prior to the index TKA were at 31% increased relative risk of revision (for any cause), and 18% increased relative risk for deep surgical infection requiring surgery, at 3-year follow-up.

How much is enough for total knee arthroplasty?

“…However, we would argue that the true surgical volume is the most important factor when determining the risk of revision in TKA surgery, as demonstrated by our study. 1 The findings in our study are echoed in the analysis by Yu et al, which concluded that from a number of outcomes evaluated, only surgical volume was associated with an increased risk of TKA 30-day readmission. 2 While it is recognized that highly experienced orthopaedic surgeons may deliver excellent patient outcomes regardless of a minimum volume, evidence suggests that higher surgical volumes result in better patient outcomes.…”

“…However, we would argue that the true surgical volume is the most important factor when determining the risk of revision in TKA surgery, as demonstrated by our study. 1 The findings in our study are echoed in the analysis by Yu et al , which concluded that from a number of outcomes evaluated, only surgical volume was associated with an increased risk of TKA 30-day readmission. 2 …”

“…In our study, the use of a spline also enabled the identification of a threshold of volume of 70 cases at which the greatest patient benefit is obtained. 1 This RCSR method was also used by Chou et Open access surgeon volume threshold of 15 cases per annum for reducing the 30-day unplanned readmission rates. 8 As our paper concluded, surgeons who had performed less than 70 TKA procedures in the year prior to the patient's index TKA had a 31% increased risk of revision and an 18% increased risk of deep surgical infection requiring further surgery at 3 years of follow-up.…”

“…8 As our paper concluded, surgeons who had performed less than 70 TKA procedures in the year prior to the patient's index TKA had a 31% increased risk of revision and an 18% increased risk of deep surgical infection requiring further surgery at 3 years of follow-up. 1 In terms of what institutional/structural changes that we suggest armed with this knowledge, we use an example from the UK. In the UK, The Getting it Right First Time (GIRFT) report identified various challenges that were faced by UK orthopaedic departments to meet the arthroplasty need of an aging population.…”

How much is enough? Finding the minimum annual surgical volume threshold for total knee replacement

“…In the recent article by Okoro et al , data from nearly 170 000 TKR recipient in Ontario, Canada, were analysed using a state of the art restricted cubic spline (RCS) analysis. 5 The authors identified an inflection point for increased probability for early revision or infection at 70 annual cases, after which the risk of complications plateaued. However, risk reduction continued even beyond an annual caseload of 70, highlighting the value of treatment by high-volume surgeons.…”