Summary

Knee arthrotomy was associated with longer operative time and greater morbidity compared to knee arthroscopy for treatment of septic knee arthritis

Abstract

Introduction

A recent study published in Arthroscopy by Grauer et al. examined 30 day complications following knee septic arthritis irrigation and debridement comparing arthroscopic versus arthrotomy as operation of choice. The study demonstrated some trends towards increased minor complications after knee arthrotomy when compared to arthroscopy. However, the study was only powered to detect a difference of ~15%. The purpose of this study was to increase the sample size and re-evaluate the question of if there was any difference in 30 day complications following arthrotomy versus arthroscopy for the treatment of septic knee arthritis.

Methods

Patients undergoing knee arthroscopy and knee arthrotomy between 2006-2016 were identified in the American College of Surgeons National Surgical Quality Improvement Program. Patient’s without a primary diagnosis of septic knee arthritis were excluded from the study. The use of open arthrotomy compared to an arthroscopic surgical treatment was analyzed for its effect on the following outcomes: operative time, reoperation, hospital length of stay, readmission, and morbid events. Morbid events were classified as minor (transfusion, pneumonia, wound dehiscence, urinary tract infection and renal insufficiency) and serious (wound infection, thromboembolic event, renal failure, myocardial infarction, prolonged ventilation, unplanned intubation, sepsis/septic shock, and death). Multivariate analysis adjusted for demographics and patient comorbidities.

Results

A total of 1,270 patients met inclusion criteria with 454 patients undergoing knee arthrotomy and 816 patients undergoing knee arthroscopy. Patients undergoing knee arthrotomy had significantly higher ASA scores (2.8 ± 0.7 versus 2.6 ± 0.75; p=0.0003) compared to patients undergoing arthroscopy. After adjusting for potential confounders from demographics and ASA scores, knee arthrotomy was associated with an increased risk for increased operative time [Parameter estimate 4.555 (95% CI:3.023, 6.085); p<0.0001], risk of a minor morbid event [OR 2.064 (95% CI: 1.447, 2.943); p<0.0001], and risk of any morbidity [OR 2.285 (95% CI:1.527, 3.419); p<0.0001].

Discussion And Conclusion

It is possible that previous published studies may have been underpowered to detect difference in 30 day complications following treatment of septic knee arthritis arthroscopically compared to open surgery. Arthrotomy was independently associated with increased risk for longer operating time, minor morbid events and any morbid events.