Alterations of kinematics in knees after single versus multiple radius femoral prostheses total knee arthroplasty: a retrospective study

Abstract

Background Design modifications in prostheses may cause alterations in gait kinematics, thus influencing functional restoration of knees after total knee arthroplasty (TKA). The aim of the study was to investigate the differences in gait kinematics and clinical outcomes after single radius (SR) versus multiple radius (MR) TKA. Method The present retrospective study included 38 unilateral TKA involving 20 knees using MR design implant and 18 knees using SR design implant. Thirty-six healthy volunteers were also recruited. The mean follow-up time was 16 ± 3 months. At the end of follow-up, the 6 degrees of freedom (DOF) kinematics of knees and range of motion (ROM) were measured with a portable optical tracking system. Knee society score (KSS) and knee injury, and osteoarthritis outcome score (KOOS) were also collected. Results Patients in the SR group had significantly higher scores in activities of daily living (84.7 ± 15.9) and sports and recreation (67.5 ± 25.2) KOOS sub-score than MR group (69.9 ± 17.6, P = 0.012; 50.0 ± 20.8, P = 0.027, respectively). Significant differences were detected between MR knees and SR knees (1.82° ± 3.11° vs 4.93° ± 3.58°, P = 0.009), and MR knees and healthy knees (1.82° ± 3.11° vs 3.62° ± 3.52°, P = 0.032) in adduction/abduction ROM. The proximal/distal translation was significantly smaller in MR knees (0.58 ± 0.54 cm) compared with SR knees (1.03 ± 0.53 cm, P = 0.003) or healthy knees (0.84 ± 0.45 cm, P = 0.039). SR knees (0.24 ± 0.40 cm) had smaller translation compared with the MR group (0.54 ± 0.33 cm, P = 0.017) and control group (0.67 ± 0.36 cm, P = 0.028). No significant difference was detected in the other DOFs during the gait cycle. Significant difference was detected in extension/flexion, internal/external rotation, adduction/abduction, proximal/distal and medial/lateral among MR, SR and healthy knees. Conclusion After TKA, patients have altered gait kinematics compared with the control group. MR and SR design showed varied characteristics in 6 DOF gait kinematics, which could be the cause of the difference in functional outcome.

Biomechanically based Fu’s subcutaneous needling treatment for senile knee osteoarthritis: protocol for a randomized controlled trial

“…The DOFs rotating around the coordinate axes includes: internal/external rotation angle, internal/external flip angle, flexion/extension angle. The DOFs translated along the coordinate axes includes: anterior/posterior displacement, superior/inferior displacement, and internal/external displacement [ 32 , 33 ]. During practice, the participant is asked to undergo approximately 2–3 min of acclimatization.…”

Similar kinematic patterns between revision total stabilized (TS) and primary posterior stabilized (PS) knee prostheses: a prospective case–controlled study with gait assessment

“…In a fluoroscopic assessment of the knee during exercise, Pandit et al reported that in the sagittal plane, a more “natural kinematic” design of a posterior‐stabilized implant allows for greater movement and is more physiological [30], and is associated with improved physiological restitution of the gait in flexion–extension [22, 23, 25].…”

Kinematic study of the overall unloading brace for the knee

“…The 6DOF values obtained for the right knee joint with and without the OUB were analyzed for all subjects, with proximal-distal translation, abduction-adduction rotation, and internal-external rotation of the knee joint serving as primary reference indexes, and with internal-external translation, anterior-posterior translation, flexion-extension angle serving as secondary indexes. Among the primary indices, proximal-distal translation may reflect knee joint gap [ 21 ], abduction-adduction rotation can reflect variation of the inner and outer loads in the TF joint [ 22 ], and internal-external rotation can reflect comfort to some degree; the secondary indices can reflect the contribution of a brace to knee joint stability.…”