Bicruciate Substituting System Can Trigger Complications After TKA

Patients who received a bicruciate substituting system after total knee arthroplasty experienced comparable knee flexion characteristics and clinical and functional outcomes but had more complications compared with patients who received a conventional posterior stabilized system, according to recent study results.

Researchers randomly assigned 124 patients with osteoarthritis to receive bicruciate substituting or conventional posterior stabilized prostheses. The study’s primary outcome was the maximum flexion angle at one year postoperatively on a lateral radiograph made while the patient was supine and using manual force to bend the knee. Secondary outcomes included active flexion, Knee Society Score, Patella Scoring System score, University of California-Los Angeles score, number and type of adverse device effects and VAS satisfaction up to two years postoperatively. The researchers compared the outcome measures of both groups using one-sided t tests and non-parametric alternatives.

At baseline, the researchers found no significant differences between the two groups in maximal flexion on radiographs and in active flexion. For the bicruciate substituting group, results showed a median maximal flexion on radiographs of 127 degrees, compared with 125 degrees in the conventional posterior stabilized group.

Two-year results among the two groups were comparable with respect to the Knee Society Score, the Patella Scoring System, the University of California-Los Angeles score and visual analog scale satisfaction. However, 41 adverse device effects were reported in 26 patients in the bicruciate substituting group, including three total system revisions and 14 manipulations under anesthesia, whereas only 16 adverse device effects were reported in 13 patients in the conventional posterior stabilized group, including six manipulations under anesthesia.