Abstract
Aim
To compare outcomes of PJI in relation to treatment method versus classification using the JS-BACH system.
Method
Patients having surgery for EBJIS Criteria Confirmed PJI between 2010–2015 were included. Index surgical procedures were 1-stage or 2-stage revision or debridement and implant retention (DAIR). Patients completed the EuroQol EQ-5D-3L questionnaire and were followed clinically to a median of 4.7 years (IQR 2.7–6.7 years). Patients were stratified using the JS-BACH classification1 into either ‘Uncomplicated’, ‘Complex’ or having ‘Limited treatment options’, by two separate classifiers, blinded to clinical outcome.
Results
216 patients met the inclusion criteria. There were 51 patients classified as Uncomplicated (23.6%), 127 (58.8%) as Complex and 38 (17.6%) having Limited treatment options. Patients underwent either DAIR (n=97), 1-stage (n=35) or 2-stage (n=84) revision. Patients classified as Uncomplicated PJI had the lowest risk of recurrence or treatment failure, regardless of index procedure performed. Complex patients were significantly more likely than Uncomplicated patients to have recurrence following 2-stage revision (Odds Ratio 1.85; p=0.040) or DAIR (OR 1.83; p=0.037), but not 1-stage revision (OR 0.518; p=0.675). Limited treatment option patients had the highest recurrence risk regardless of index procedure (1-stage: OR 2.5 p=0.036; 2-stage: OR 3.3 p=0.004; DAIR: OR 3.40 p=0.006).
At one year after surgery, Uncomplicated patients had the highest EQ-index scores (a marker of Quality of Life), with all treatments (EQ-5D-3L mean index scores; Uncomp 0.773, Complex 0.512, Limited Options 0.310: p<0.01). Differences in patient-reported outcomes were greater between the JS-BACH classification groups than between any methods of treatment.
Conclusions
The JS-BACH classification effectively predicted outcome after three common PJI treatments. Comparing outcomes between treatments, without stratification of the patients, may be misleading as factors other than treatment method have a major effect on outcome. Classification may allow better allocation of individual treatments to provide optimal outcome for patients.