Knee surgery and comorbidities

COVID-19 has had a profound impact on elective surgery. The sheer volume of patients waiting for surgery has presented countries across the world with a logistical challenge. Crisis is an opportunity for change, and recovery programmes have focussed on working smarter and more efficiently. Initiatives have included prehabilitation, day surgery arthroplasty, reducing inpatient stay and improving the postoperative monitoring for patients.

Reducing unwanted re-admission due to complications is key to efficient use of limited bed space. Whilst fit and healthy patients requiring knee replacement are a minimal burden on resources, those with comorbidities present more of a challenge. Studies have shown the effect of comorbidities on the short term risks relating to the safety of the surgery and are resource heavy, but there is little evidence that single or multiple comorbidities impact deleteriously on the effectiveness of surgery [

,

].

Socioeconomic inequality can also impact on resourcing service provision with hospitals serving a lower socioeconomic population noting a greater occurrence of comorbidities. A recent study by Nuzhat et al of a ‘safety-net hospital’ serving one of the poorest districts in the United States found that only 5% of their arthroplasty population had no comorbidities. Conversely 26% had one or more psychiatric issues with the most common comorbidities including hypertension, obesity, diabetes, anaemia and valve disorder [

].

Our current issue includes two papers investigating the effects of Crohn’s disease and organ transplant on arthroplasty outcomes. Kim and colleagues investigated Crohn’s disease in total knee arthroplasty (TKA) patients and its impact on post-operative complications [

]. They analysed a cohort of 89,134 TKAs of which 244 had a diagnosis of Crohn’s disease. They found that a diagnosis of Crohn’s disease was an independent risk factor for renal failure, blood transfusions and pulmonary embolus.

Upfill-Brown and colleagues also used a large national database to investigate outcomes in solid organ transplant patients [

]. Their national database of 303,867 revision TKAs included 464 with solid organ transplants, of which 182 were performed for prosthetic joint infection. The transplant cohort included 53% with a kidney transplant and 34.3% with a liver transplant. Of interest in this study was that there was no difference in over-all 90 day readmission or mortality for this group when matched for overall medical comorbidity.

With the long term effects of symptomatic and asymptomatic COVID-19 infection as yet still largely unknown, the impact on outcome of joint arthroplasty is an area for further research.