| Methods |
RCT. Unknown randomization technique. Double‐blind. |
| Participants |
Twenty‐one participants: osteoarthrosis (5 knees) and rheumatoid arthritis (26 knees). Average age: 68 years. Three participants (3 knees) were lost. |
| Interventions |
Fixation with cement, without cement, or with a hydroxyapatite coating (without cement) was randomly chosen during the operation. All of the prostheses were posterior cruciate ligament‐retaining total condylar implants (Interax; Howmedica, Rutherford, New Jersey). A patellar component made of ultra‐high molecular weight polyethylene was used in all but one total knee arthroplasty. No patellar components were used in one knee because the remaining patellar bone was too thin. |
| Outcomes |
RSA, Knee Society score, conventional roentgenograms, length of surgery (in minutes) and femorotibial angle. |
| Notes |
Duration of follow‐up: 2 years. A significant difference with regard to micromotion was found between the non‐coated components fixed without cement and the hydroxyapatite‐coated components fixed without cement and between the non‐coated components fixed without cement and the components fixed with cement (P < 0.001, analysis of variance). The hydroxyapatite‐coated components fixed without cement and the components fixed with cement both had far less micromotion along the longitudinal axis (subsidence) throughout the follow‐up period than the non‐coated components fixed without cement. |
