Influence of total knee arthroplasty on patellar kinematics and contact characteristics

Purpose The aim of the study was to compare femoropatellar alignment and the incidence of lateral retinacular release (LRR) in total knee arthroplasty (TKA) in which the rotational alignment of the femoral component was determined using a combination of different rotational alignment axes and navigation or a single reference axis in the standard procedure. Methods We assessed 66 patients undergoing TKA in whom the rotation of the femoral component was determined on the posterior condylar axis in standard procedures (group A) and 65 patients in whom it was determined by combining the posterior condylar axis, anteroposterior axis and epicondylar axis in navigated procedures (group B). The mean age was 68 and 69 years in groups A and B, respectively. Patellar tracking was assessed after deflation of the tourniquet and LRR performed in the presence of maltracking. Visual analogue scale (VAS), Knee Society Score (KSS), Lonner patellar score and patellar tilt were recorded. Results LRR was carried out in 18 cases (27 %) in group A and in four (6 %) in group B (p00.003). The KSS and VAS were improved significantly compared to the preoperative status, but with no significant differences between the two groups. The patellar score showed a greater improvement in the navigated compared to the standard group at the four week follow-up. Patella tilt improved significantly in both groups. The complication rate was similar in the two groups. Conclusions Combining different rotational alignment axes with navigation significantly reduces patellar maltracking and the need for LRR compared to the standard procedure in which the posterior condylar axis is used as single anatomical reference.

Section: Discussionmentioning

confidence: 99%

Combining different rotational alignment axes with navigation may reduce the need for lateral retinacular release in total knee arthroplasty

Cinotti

Ripani

Sessa

et al. 2012

“…Rotational alignment of the tibial and femoral components is an important factor influencing patellar tracking. A malpositioned femoral component increases the patellofemoral contact pressure, thus affecting the clinical outcome and the long-term survivorship of the implant [6,12]. However, in patients with persistent AKP after TKA, the source of symptoms cannot be identified [2,3,14].…”

Section: Introductionmentioning

confidence: 97%

Patellar resurfacing as a second stage procedure for persistent anterior knee pain after primary total knee arthroplasty

Daniilidis

Vogt

Gosheger

et al. 2012

Purpose Knee pain after total knee arthroplasty may be caused by an unresurfaced patella. Secondary isolated resurfacing of the previously unresurfaced patella in total knee arthroplasty remains controversial. The aim of this retrospective study was to evaluate the outcome after patellar resurfacing as a second stage procedure. Methods The study included 22 patients (13 female/nine male) who underwent resurfacing of the patella with a mean follow-up of 61.8±39.2 months. The mean age of the patients was 60±9.7 years at the time of operation. The average period between total knee arthroplasty and patellar resurfacing was 26.3±15.2 months. The patient's subjective satisfaction was assessed by a custom-made questionnaire.

“…The results of our study supported their suggestion. This may be also because, as Kainz [41] suggested, the patella sits deeply in the trochlear groove, and its kinematics are predominantly controlled by the geometry of the groove in deep flexion. It is considered that our results showing the increment of patella tilt after ADVANCE MP prosthesis is not so unfavorable for patients.…”

Section: Discussionmentioning

confidence: 99%

Evaluation of patellofemoral joint in ADVANCE® Medial-pivot total knee arthroplasty

Chinzei

Ishida

Matsumoto

et al. 2013

Purpose ADVANCE® Medial Pivot (MP) (Wright Medical) total knee arthroplasty (TKA) was established to replicate normal tibio-femoral knee joint kinematics, however, its influence on the patello-femoral (PF) joint is unclear. The purpose in this study was to assess the PF joint conditions in Advance MP TKA, via radiography and three-dimensional image-matching software. Methods Ten subjects with osteoarthritis were treated with the ADVANCE MP TKA. Pre-operatively and one month after surgery, skyline views at 30, 60, and 90°of flexion were taken, and patella shift and tilt were measured. With 2D-3D registration techniques using software, implant orientations were matched with the pre-operative CT and changes in the anterior part of the femoral prosthesis, condylar twist angle (CTA) for femoral rotation, and tibial rotation were evaluated. The relationships between morphological and rotational changes were evaluated. Results There were significant differences in patella tilt at 60°a nd patella shift at all angles between pre-and post-operation (p<0.05). No correlation was found between morphological changes in the anterior femur with patella tilt and shift. A positive correlation between postoperative CTA and patella shift at 90°was found (p<0.05); however, no correlation was found between rotational alignment of the tibial component and patella tilt and shift. Conclusions ADVANCE MP TKA changed patello-femoral joint kinematics, compared to that found before surgery. The kinematic features were mainly due to the design concepts for tibio-femoral joint motion, indicating the difficulty to reproduce normal patello-femoral joint kinematics after TKA.