Purpose: Multiple needle punctures (MNPs), for gap balancing in total knee replacement, have less variability in gap widening compared to the conventional released technique. This study aimed to evaluate the outcome of gap-balancing techniques in varus osteoarthritis (OA) knees, by serial MNP, after a total knee prosthesis trial component was placed, combined with repetitive knee manipulation.
Methods: This study was a retrospective, case-matched study of 161 patients. The data were collected from varus OA knee patients, who had total knee arthroplasty by a single surgeon. Sixty-eight patients required MNP, combined with repetitive knee manipulation for gap balancing, and 93 patients did not. Both groups of MNP patients underwent the same surgical technique and postoperative care protocols.
Results: Knee society scores, in terms of knee score and functional score, were not different in both groups when we started the study, at 6-month and 1-year follow-ups (p > 0.05). The femorotibial angle was not significantly different between groups at the start of the study, initial postoperative, 6 months, and 1 year (p = 0.74, 0.45, 0.99, and 0.82, respectively). Medial joint opening in knee radiographic was found in 3% of the patients in the MNP group and in 4% of patients in the control group at 1-year follow-up (p = 0.65).
Conclusion: This study found MNP combined with repetitive knee manipulation was effective, reproductive, and a safe method for varus OA knee. We believe that the cycle of performed needle punctures, knee manipulation, and reevaluation could gradually lengthen the medial soft tissue without risk of over lengthening or medial collateral ligament rupture.
Keywords: balancing; multiple needle punctures; total knee arthroplasty.