Gama angle in sagittal plane of post-operative total knee replacement - variations in patients: A retrospective radiological analysis

Having demonstrated in Chapter 2 that a fully conforming mobile bearing can minimise polyethylene wear, in this chapter we show that a mobile bearing prosthesis, unconstrained in the sagittal plane, can restore natural mobility and stability. For surgeon readers who are less interested in the theoretical background, it might be advisable to go straight to Chapter 4, Indications, or to start by reading the final section of this chapter, The Loaded Prosthetic Knee. If that proves interesting, the surgeon might attempt The Unloaded Prosthetic Knee. For the more research minded surgeon or engineer, it seems more logical to start with the Unloaded Natural Knee (the longest section of the chapter) and to read from there. The chapter may also be of interest to those surgeons embarking on the use of a bi-cruciate retaining total knee replacement.

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Total Knee Arthroplasty after Correction of Tibial Diaphyseal Nonunion with Clamshell Osteotomy

Case Reports in Orthopedics ◽

10.1155/2018/2632963 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6

Author(s):

Pingal Desai ◽

Vivek Sharma ◽

Karanvir Prakash

Keyword(s):

Total Knee Arthroplasty ◽

Total Knee Replacement ◽

Lower Extremity ◽

Knee Replacement ◽

Knee Arthroplasty ◽

Sagittal Plane ◽

Osteotomy Site ◽

Relieve Pain ◽

Total Knee ◽

Made In

Total knee arthroplasty is mostly done to relieve pain and disability from a severe and degenerated knee. Deformities in the coronal and sagittal plane could be corrected with the help of cuts made in tibia and femur during total knee replacement as well as with ligament release. However, large deformities in the lower extremity particularly in the diaphysis region need correction prior to the total knee replacement. It helps to limit the amount of bone that will be cut and helps the ligament release. Several extra articular and intra-articular methods for the correction of diaphyseal deformity have been described. We present the case of clamshell osteotomy for the correction of diaphyseal deformity in the tibia and a total knee replacement after the osteotomy site healed.

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A computational model for the prediction of total knee replacement kinematics in the sagittal plane

Journal of Biomechanics ◽

10.1016/s0021-9290(99)00183-9 ◽

2000 ◽

Vol 33 (4) ◽

pp. 435-442 ◽

Cited By ~ 20

Author(s):

A.-C Godest ◽

C Simonis de Cloke ◽

M Taylor ◽

P.J Gregson ◽

A.J Keane ◽

...

Keyword(s):

Total Knee Replacement ◽

Computational Model ◽

Knee Replacement ◽

Sagittal Plane ◽

Total Knee

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Long-term implant—bone fixation of the femoral component in total knee replacement

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1243/09544119jeim328 ◽

2008 ◽

Vol 222 (3) ◽

pp. 319-331 ◽

Cited By ~ 20

Author(s):

L Cristofolini ◽

S Affatato ◽

P Erani ◽

W Leardini ◽

D Tigani ◽

...

Keyword(s):

Total Knee Replacement ◽

Femoral Component ◽

Knee Replacement ◽

Sagittal Plane ◽

Clinical Test ◽

Migration Patterns ◽

Bone Fixation ◽

Total Knee

Success of total knee replacement (TKR) depends on the prosthetic design. Aseptic loosening of the femoral component is a significant failure mode that has received little attention. Despite the clinical relevance of failures, no protocol is available to test long-term implant—bone fixation of TKR in vitro. The scope of this work was to develop and validate a protocol to assess pre-clinically the fixation of TKR femoral components. An in vitro protocol was designed to apply a simplified but relevant loading profile using a 6-degrees-of-freedom knee simulator for 1 000 000 cycles. Implant—bone inducible micromotions and permanent migrations were measured at three locations throughout the test. After test completion, fatigue damage in the cement was quantified. The developed protocol was successfully applied to a commercial TKR. Additional tests were performed to exclude artefacts due to swelling or creep of the composite femur models. The components migrated distally; they tilted towards valgus in the frontal plane and in extension in the sagittal plane. The migration patterns were consistent with clinical roentgen-stereophotogrammetric recordings with TKR. Additional indicators were proposed that could quantify the tendency to loosen/stabilize. The type and amount of damage found in the cement, as well as the migration patterns, were consistent with clinical experience with the specific TKR investigated. The proposed pre-clinical test yielded repeatable results, which were consistent with the clinical literature. Therefore, its relevance and reliability was proved.

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