Comparison of joint line position changes after primary bilateral total knee arthroplasty performed using the navigation-assisted measured gap resection or gap balancing techniques.

PURPOSE

This study aimed to compare the clinical and radiological results of navigation-assisted TKAs performed using the measured gap resection or the gap balancing technique in thirty patients who underwent bilateral primary TKAs.

METHODS

Sixty cases of navigation-assisted TKAs [30 TKAs performed using the measured gap resection technique (Group A) and 30 TKAs performed using the gap balancing technique (Group B)] were analyzed prospectively with minimum follow-up of 2 years. The joint line positions were measured using preoperative and postoperative weight-bearing anteroposterior and lateral radiographs. Clinical results were evaluated using knee scores and functional scores.

RESULTS

No significant differences in knee scores or functional scores were observed. Polyethylene thickness and flexion/extension gaps were significantly larger in Group B (P < 0.05). The meaningful proximal shift of the joint line was shown in Group B (P < 0.05).

CONCLUSION

The navigation-assisted TKA with measured gap resection technique could be a useful technique with regard to restoration of the joint line.