2015 ISAKOS Biennial Congress ePoster #1405
Do We Have to Resurface the Patella in Total Knee Arthroplasty for Rheumatoic Arthritis All the Time?
Choong-Hyeok Choi, MD, PhD, Seoul KOREA, REPUBLIC OF
Jin-Kyu Lee, MD, Seoul KOREA, REPUBLIC OF
Chang Hoon Lee, MD, Seoul KOREA, REPUBLIC OF
Il-Hoon Sung, Prof, Seoul KOREA, REPUBLIC OF
Dong Won Kim, Prof, Seoul KOREA, REPUBLIC OF
Department of Orthopaedic Surgery, Hanyang University Hospital, Seoul, KOREA
FDA Status Not Applicable
Summary: Equivalent results after TKA were obtained with or without patellar resurfacing in patients with rheumatoid arthritis
Patellar resurfacing in patients with rheumatoid arthritis during total knee arthroplasty (TKA) remains controversial. However, very few studies have compared results of TKA with and without patellar resurfacing in patients with rheumatoid arthritis. In this prospective comparative study, we sought to compare clinical and radiological outcomes after TKA with or without resurfacing patellar in patients with rheumatoid arthritis. In addition, satisfactory scales were compared between the two groups.
Materials And Methods
89 consecutive rheumatoid arthritis patients (110 knees) who underwent primary TKA from August 2006 to April 2011 by a single surgeon were assessed. Patients with prior hip or spine surgery, vertebral fracture, and those with a history of revision for infected TKA were excluded. In addition, 5 patients (6 knees) who had died during follow-up period were also excluded. Accordingly, 76 patients (90 knees) were enrolled for the study. There were 65 women and eleven men with a mean age at operation of 56 years (range, 34 to 73). They were followed up for a mean of 54 months (range, 30 to 87). Patellae were resurfaced in 56 TKAs (PR group), and non-resurfaced in 34 TKAs (PN group). The indications for patellar retention were a thin patellar (<20 mm thickness), nearly normal articular (ICRS grade 0 or 1) cartilage of patellar, and minimal preoperative anterior knee pain. All patients were asked to complete a questionnaire so as to determine Knee Society score, Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC) score, Feller patellar score, and Samsung Medical Centre (SMC) patellofemoral score. In addition, satisfaction scales focusing on satisfaction with walking, going up or down stairs, and sitting or lying were also evaluated. For radiological assessments, Ahlback criteria for patellofemoral osteoarthritis (0=normal; I= narrowing; II=obliteration; III=bone destruction <5mm), mechanical axis of lower limb, Insall-Salvati ratio, patellar tilt and subluxation were compared between the two groups.
Demographic and preoperative clinical parameters including sex, age, implant type, and follow-up period were comparable between the two groups (p>0.05). However, mean age at the time of TKA of PN group was younger (53.54±8.84 vs 58.57±10.23, p=0.02) than PR group. Preoperative radiological parameters including Ahlback criteria, mechanical limb axis, and patellar tilt and subluxation were similar between the two group (p>0.05). We failed to identify any significant differences in terms of clinical parameters including Knee Society score, Feller patellar score, SMC patellofemoral score, and patient satisfaction scales. However, PN group showed better outcome in ‘stiffness subscale’ of WOMAC score (0.59±0.78 vs 1.02±0.88, p=0.02), although total WOMAC score was not different between the two groups (p=0.297). Postoperative radiological parameters including mechanical limb axis, Insall-Salvati ratio, and patellar tilt and subluxation were similar between two groups (p>0.05).
Equivalent results after TKA were obtained with or without patellar resurfacing in patients with rheumatoid arthritis.