Outcomes of primary total knee arthroplasty in patients with Parkinson’s disease: A Case Control Comparison Study

Abstract

Introduction and Aims: There is considerable debate and a paucity of evidence regarding whether Total Knee Replacement (TKR) is of benefit in patients with Parkinson's disease (PD) and knee osteoarthritis, and whether PD would compromise the outcome of TKR. Therefore, we aimed to compare the effect of TKR on range of motion and Oxford Knee Scores (OKS) between PD patients and age-matched controls at 1 year follow-up. Method(s): A cohort of 45 knees from 35 patients was identified as having a confirmed diagnosis of Parkinson's disease and received a primary TKR between January 2004 and December 2015, which was extracted from a clinical database (Socrates, v3.5, Orthosoft, AUS) maintained by two orthopaedic surgeons in two hospitals. An age-matched control group (mean age: 73 years) of 45 knees from 41 patients without Parkinson's disease was randomly computer-generated from the same database. The indication for TKR in both groups was osteoarthritis, an independent assessment of each knee to meet appropriate selection criteria for TKR, as well as preoperative physician review for medical comorbidities. Outcome measures analysed in the study were the difference in pre-operative range of motion (RoM) and 12-point Oxford Knee Scores and at 1-year follow-up respectively. Postoperative complications and revisions were also recorded during the follow-up period. Result(s): In the PD group, RoM improved from a mean of 100 degrees preoperatively to 114 degrees at 12 months, compared to the control group which improved from a mean of 102 degrees to 114 degrees respectively. OKS in the Parkinson's group improved from a mean of 23 preoperatively to 38 at 12 months compared to 23 preoperatively and 40 at 12 months in the control group. After adjusting for sex, we found that the difference in the ROM and OKS between the Parkinson's and control groups was not significantly different (p = 0.9725; 0.6450 respectively). Furthermore, in all Parkinson's patients the minimal clinically important difference for OKS (>=6) was achieved at 1-year follow-up (4). There were no mortalities during the study follow-up period, with 4 complications in the PD group (DVT, superficial infection) and two in the control group (DVT, bowel pseudo-obstruction). Conclusion(s): This study demonstrates that TKR provides comparable outcomes with regard to range of movement and ambulatory function in patients with Parkinson's disease who are also suffering from severe osteoarthritis. We also feel that TKR has an acceptable complication profile in this subgroup of patients. The presence of PD does not appear to compromise the outcome of TKR in these patients, and the same indications for TKR should therefore apply as for the general OA population.