Paget's disease of bone (PDB) is the second most common metabolic bone disease. Osteoarthritis (OA) affects one-third of patients with PDB. The incidence of THR (total hip replacement) and TKR (total knee replacement) is 3.1- and 1.7-fold higher in PDB patients compared to non-affected age-matched controls. No large studies or joint registry reports exist describing the outcomes following THR or TKR in patients with PDB.

The objectives of this study were to investigate the outcomes following THR and TKR in patients with PDB using national joint registry data. 144 THR and 43 TKR were identified using the Scottish Arthroplasty Project from 1996–2013.

For THR, the most common early post-operative surgical complications were haematoma formation (1.4%), and surgical site infection (1.4%). The absolute incidence during follow-up of dislocation was 2.8%, and revision hip arthroplasty was performed in 2.8% of cases. Implant survival of the primary prosthesis was 96.3% (CI: 92.8 – 99.8) at 10-years, and patient survival was 50.0% (39.6 – 60.4) at 10-years.

For TKR, the most common early post-operative surgical complication was surgical site infection (2.3%). The absolute incidence during follow-up of revision knee arthroplasty was 4.7%. On survival analysis, implant survival of the primary prosthesis was 94.5% (CI: 87.1 – 100) at 10-years, and patient survival was 38.3% (16.7 – 59.9) at 10-years.

This is the largest reported series of outcomes following primary THR and TKR in patients with PDB. PDB patients are not at increased risk of surgical complications following primary THR or TKR compared to non-PDB patients.