Save
Kinematical analysis of a medial stabilized total knee arthroplasty during sit to stand and lunge: an in vivo dynamic RSA study
ESSKA Academy. Zaffagnini S. Nov 8, 2019; 284377; epEKA-39 Topic: Biomechanics
Prof. Dr. Stefano Zaffagnini
Prof. Dr. Stefano Zaffagnini
Login now to access Regular content available to all registered users.

You can access free non-premium educational content on the ESSKA Academy Portal by registering for free as 'ESSKA Academy User' here
Abstract
Discussion Forum (0)
Rate & Comment (0)
Kinematical analysis of a medial stabilized total knee arthroplasty during sit to stand and lunge: an in vivo dynamic RSA study

ePoster - epEKA-39

Topic: TKA

Marcheggiani Muccioli G.M.1, Alesi D.1, Roberti di Sarsina T.1, Cardinale U.2, Bontempi M.2, Zinno R.2, Di Paolo S.2, Bragonzoni L.2, Neri M.P.1, Zaffagnini S.1
1IRCCS Istituto Ortopedico Rizzoli, II Orthopaedic and Traumatologic Clinic, Bologna, Italy, 2Università di Bologna, Bologna, Italy

Introduction: A new model of medial stabilized (MS) total knee prosthesis has a high spherical congruence of the internal compartment which guarantees anteroposterior stability (AP) associated with a flat surface of the insert in the lateral compartment that allows a greater AP translation of the external condyle during knee flexion. The purpose of our study was to evaluate, by dynamic radiostereometric analysis (RSA), the in vivo kinematics of the knee after implantation of a mechanically aligned MS prosthesis during sit to stand and lunge movements.
Objectives: To evaluate the presence of medial pivot during knee flexion. We expected also that no significant differences would be present between the kinematics of the two examined tasks.
Aims: The aim of this study was to understand the effect of implant design and surgical technique on the kinematics of prosthetic knees during dynamic activities.
Methods: A cohort of 18 patients (72.1 ± 7.4 years old), after signing informed consent, was prospectively evaluated by dynamic RSA 9 months after surgery. The kinematic evaluation was carried out using the dynamic RSA tool, during the execution of sit to stand and lunge movements. The kinematic data were processed using the Grood and Suntay decomposition and the Low Point method.
Results: During the sit to stand the kinematic analysis showed the presence of a medial pivot, with a significantly greater (p=0.0216) anterior translation of the lateral condyle (3.9 ± 0.8 mm) than the medial one (1.6 ± 0.8 mm) associated with a femoral internal rotation (4.5 ± 0.9 deg). In the lunge, the lateral condyle showed a larger posterior translation with respect to the medial one (6.2 ± 0.8 mm vs 5.3 ± 0.8 mm) associated with a femoral external rotation (3.1 ± 0.9 deg) in the flexion phase, followed by a larger anterior translation of the lateral condyle respect to the medial one (5.8 ± 0.8 mm vs 4.6 ± 0.8 mm) associated with femoral internal rotation (6.2 ± 0.9 deg) in the extension phase. Analyzing individual kinematic, we found also a negative correlation between clinical scores and VV laxity during sit to stand (R= -0.61) and that the higher femoral extra-rotation, the poorer clinical scores (R= 0.65).
Conclusions: The MS prosthesis simulates in vivo the physiological kinematics of the knee described by Freeman and Pinskerova. It allows greater AP translation of the lateral compartment associated with a medial pivot during flexion in weightbearing conditions.
Code of conduct/disclaimer available in General Terms & Conditions
Anonymous User Privacy Preferences

Strictly Necessary Cookies (Always Active)

MULTILEARNING platforms and tools hereinafter referred as “MLG SOFTWARE” are provided to you as pure educational platforms/services requiring cookies to operate. In the case of the MLG SOFTWARE, cookies are essential for the Platform to function properly for the provision of education. If these cookies are disabled, a large subset of the functionality provided by the Platform will either be unavailable or cease to work as expected. The MLG SOFTWARE do not capture non-essential activities such as menu items and listings you click on or pages viewed.


Performance Cookies

Performance cookies are used to analyse how visitors use a website in order to provide a better user experience.



Google Analytics is used for user behavior tracking/reporting. Google Analytics works in parallel and independently from MLG’s features. Google Analytics relies on cookies and these cookies can be used by Google to track users across different platforms/services.


Save Settings