Medial pivot vs posterior stabilized total knee arthroplasty designs: a gait analysis study
Nicola Bianchi, Andrea Facchini, Nicola Mondanell, Federico Sacchetti, Roberta Ghezzi, Marco Gesi, Rodolfo Capanna, Stefano Giannotti
Abstract
<p><strong>Aim</strong> <br />To compare a medial pivot (MP) total knee arthroplasty (TKA) with posterior stabilized (PS) TKA designs from a subjective, clinical and biomechanical point of view, in a single-centre, single-surgeon, case-control non-randomized trial.<br /><strong>Methods</strong> <br />Sixteen patients were randomly picked up from case series into each group. Subjective outcome was assessed using the<br />Forgotten Joint Score Questionnaire (FJSQ). Clinical evaluation included range of motion (ROM). All patients underwent gait analysis by a treadmill with force-measuring plaques and videorecording device; data were recorded for 30 seconds and included cadence, step length, stance time and walking speed. A blinded qualitative analysis of the pattern of gait was defined as biphasic or non-biphasic. Descriptive statistics for the continuous study variables and statistical significance were calculated for all parameters with independent-samples t-test and χ2 test to analyse difference in pattern of gait between groups.<br /><strong>Results</strong> <br />Mean FJSQ in the MP group was 91.87 (CI 95%: 88.12- 95.46) and 75.31 (CI 95%: 67.97-81.56) in the PS group (p=0.029). Mean post-operative ROM was 117° (CI 95%: 113°-122°) in the MP group and 112° (CI 95%: 108°-117°) in the PS group (p=0.14). No statistical difference was found between groups regarding all gait analysis parameters which have been recorded.<br /><strong>Conclusion</strong> <br />MP TKA design showed better subjective results using the FJSQ, but it did not improve significantly clinical and<br />functional outcomes compared to PS TKA design, at a short-term follow-up.</p>