Standard Test Method for Determination of Total Knee Replacement Constraint

Importancia y uso:

4.1 This test method, when applied to available products and proposed prototypes, is meant to provide a database of product functionality capabilities (in light of the suggested test regimens) that is hoped will aid the physician in making a more informed total knee replacement (TKR) selection.

4.2 A proper matching of TKR functional restorative capabilities and the recipient's (patient’s) needs is more likely to be provided by a rational testing protocol of the implant in an effort to reveal certain device characteristics pertinent to the selection process.

4.3 The TKR product designs are varied and offer a wide range of constraint (stability). The constraint of the TKR in the in vitro condition depends on several geometrical and kinematic interactions among the implant's components which can be identified and quantified. The degree of TKR's kinematic interactions should correspond to the recipient's needs as determined by the physician during clinical examination.

4.4 For mobile bearing knee systems, the constraint of the entire implant construct shall be characterized. Constraint of mobile bearings is dictated by design features at both the inferior and superior articulating interfaces.

4.5 The methodology, utility, and limitations of constraint/laxity testing are discussed.3, 4 The authors recognize that evaluating isolated implants (that is, without soft tissues) does not directly predict in vivo behavior, but will allow comparisons among designs. Constraint testing is also useful for characterizing implant performance at extreme ranges of motion which may be encountered in vivo at varying frequencies, depending on the patient’s anatomy, pre-operative capability, and post-operative activities and lifestyle.

Subcomité:

F04.22

Referida por:

F2777-23, F2887-23, F2665-21, F1357-23, F2724-21

Volúmen:

13.01

Número ICS:

11.040.40 (Implants for surgery, prothetics and orthotics)

Palabras clave:

arthroplasty; constraint; joint; laxity; prosthesis; total knee replacement;