Abstract
Non-surgical osteoarthritis management includes analgesia escalation to oral opiates; however, tolerance can occur. This study aims to assess analgesic effects of opiate use pre-operatively and whether this influences outcome 1-year post-operatively in patients undergoing total hip/knee arthroplasty (THA/TKA).
This prospective study assessed 1487 patients undergoing primary THA (n=729) or TKA (n=758) for osteoarthritis, with 95 respectively reporting pre-operative opiate use >1 month. THA opiate users had significantly higher BMI (p=0.007) and more likely to suffer associated comorbidities. TKA opiate users were significantly younger (p<0.001), with higher BMI (p=0.019) and more likely to suffer associated comorbidities. Pre-operative quality of life (QoL) and joint specific function were significantly worse (Hip EQ-5D 0.17 vs 0.41, p<0.001, OHS 14.6 vs 21.2, p<0.001; Knee EQ-5D 0.27 vs 0.44, p<0.001, OKS 16.4 vs 21.4, p<0.001). Pre-operative pain was significantly worse in those taking opioids (Hip Pain VAS 42.73 vs 50.70, p<0.001; Knee Pain VAS 50.93 vs 53.36, p=0.30). Post-operatively the THA opiate group had significant improvement in EQ-5D (0.175, p<0.001) and OHS (6.5, p<0.001) but were significantly less improved than opiate naïve patients after adjusting for confounding (EQ-5D 0.10, p<0.001; OHS 3.2, p<0.001). TKA opiate group also had significant improvement in EQ-5D (p<0.001) and OKS (p<0.001) but were significantly less (EQ-5D 0.089, p<0.001; OKS 3.9, p<0.001) than opioid naïve patients.
Pre-operative opiate use was associated with significantly worse pre-operative QoL, joint specific function and worse subjective pain. Post-operatively, the opiate group had significantly lower improvement in their QoL and joint specific function.
