Approximately 15–20% of patients report chronic pain three months after total knee replacement (TKR). The STAR care pathway is a clinically important and cost-effective personalised intervention for patients with pain 3 months after TKR. The pathway comprises screening, assesment, onward referral for treatment and follow-up over one year. In a multicentre randomised controlled trial comparing the pathway with usual care, the pathway improved pain at 6 and 12 months. This study examined the longer-term clinical and cost-effectiveness of the STAR care pathway. STAR trial participants were followed-up at a median of 4 years post-randomisation. Co-primary outcomes were self-reported pain severity and interference in the replaced knee, assessed with the Brief Pain Inventory (BPI). Resource use from electronic hospital records was valued with UK reference costs.Abstract
Introduction
Methodology
Total knee arthroplasty (TKA) remains a safe and effective intervention for the treatment of arthritis of the knee. It does, however, carry risks including death. Studies have compared the incidence of death following TKA to standardised mortality ratios of matched populations. This often suggests that TKA is protective to health in the immediate post operative phase, attributed to the lower incidence of co-morbidities in patients undergoing surgery. In an attempt to remove this “well patient effect”, we compared the incidence of death in the first 30 and 90 days following primary TKA to that of a comparable population added to a waiting list for the same procedure. All primary TKAs undertaken, and all patients added to a waiting list for the same procedure, in a single unit between 2000 and 2007 were recorded. Death rates at 30 and 90 days were compared in each group. The 30 and 90 day mortality following primary TKA were 0.295% and 0.565% respectively, compared to a 30 and 90 day mortality of 0.055% and 0.316% seen in a population of patients awaiting operation. When stratified for age, surgery conferred an excess surgical mortality in all age groups over the age of 60. Factors associated with an increased mortality following operation include male gender and increasing age. Previous studies have suggested that TKA is associated with a decreased risk of death. This study demonstrates an increased risk of death associated with surgery in comparison to a similar population deemed fit enough to undergo operation. Primary TKA carries an excess surgical mortality of 0.24% at 30 days and 0.25% at 90 days, a 5.36 and 1.79 times greater risk of death when compared to patients awaiting the same procedure. This information will greatly assist orthopaedic surgeons when counselling patients as to the risks of surgery.
