Comparison of the Imaging and Clinical Outcomes among the Measured Resection, Gap Balancing, and Hybrid Techniques in Primary Total Knee Arthroplasty

Abstract

Objective Although many studies have compared the measured resection (MR) technique to the gap balancing (GB) technique, few studies have investigated the hybrid technique. In this study, we compared imaging and clinical outcomes of the MR, GB, and hybrid techniques in primary total knee arthroplasty (TKA). Methods From January 2016 to January 2019, we conducted a retrospective study on 90 patients who underwent unilateral primary TKA; 30 received the MR technique, 30 received the GB technique, and 30 received the hybrid technique. Radiological outcomes, including joint line level, mechanical alignment of the lower limb, positions of the femoral and tibial components, and rotation of the femoral component, and clinical outcomes, including the visual analog scale score for pain, the Knee Society Score, and the range of motion, were assessed among the three groups. One‐way analysis of variance and Dunnett's test were performed for normally distributed data. Kruskal–Wallis H test and Dunn–Bonferroni test were conducted for non‐normally distributed data. Results No significant difference in the mechanical alignment (p = 0.151) and the positions of the tibial and femoral components (p = 0.230 for α angle, p = 0.517 for β angle, p = 0.686 for femoral flexion angle, and p = 0.918 for tibial slope angle) was found among the three groups. No significant difference in the elevation of the joint line between the MR and the hybrid groups was found (2.1 ± 0.3 mm vs 2.1 ± 0.1 mm, p = 0.627), but the GB group (2.8 ± 0.2 mm) differed significantly from the other two groups (p < 0.001). Although rotation of the femoral component in the GB group was larger than that of the MR and hybrid groups, the difference was not significant (1.8° ± 0.2° vs 1.7° ± 0.3° vs. 1.7° ± 0.2°, p = 0.101). The clinical outcomes were not significantly different (p > 0.05), although the results in the hybrid group were slightly higher. Conclusion The hybrid technique helped to restore the mechanical alignment of the lower limb and realize optimal positions of the femoral and tibial components without significant differences relative to the MR and GB techniques. The hybrid technique was more helpful for maintaining the original height of the joint line, which was similar to the MR technique. Additionally, although the improvement in the clinical outcomes in the hybrid group was slightly higher, it was not significantly different among the three groups.

Patella scores are similar both with gap balancing and measured resection after total knee arthroplasty: a randomized single‐centre study

“…It is well known that malrotation of the FC can cause patellofemoral problems such as patella subluxations and dislocations and post-TKA stifness as a result of reduced joint ROM [1,25,34]. As a secondary outcome, the higher PCO ratio in the GB group indicates that the FC tends to be [17,20,30,32]. In the GB technique, unlike MR, the FCR is adjusted according to the soft tissue tension provided in the extension gap, parallel with the proximal tibial cut while the knee joint is in 90° lexion and distracted with the lamina spreader.…”

“…FCR is determined by GB, MR, and combined techniques [17, 20, 30, 32]. In the GB technique, unlike MR, the FCR is adjusted according to the soft tissue tension provided in the extension gap, parallel with the proximal tibial cut while the knee joint is in 90° flexion and distracted with the lamina spreader.…”

Risk Factors for Postoperative Knee Stiffness in Patients with Anteromedial Knee Osteoarthritis Undergoing Unicompartmental Knee Arthroplasty with Cemented Prostheses: A Short-Term, Retrospective, Case-Control Study

“…Hurst et al revealed that 12% of patients experienced stiffness in their knee joints, which subsequently led to treatment failures [ 8 ]. Stiff knees can cause pain and limited function during daily activities, particularly when ascending or descending stairs, sitting or standing up, and tying shoelaces [ 9 ]. Meanwhile, more complex surgical procedures, such as surgical dissolution of scar tissue (arthroscopic or open surgery) or revision arthroplasty, are required in some recalcitrant cases to relieve pain and restore knee function [ 7 ].…”