Patients who received total knee arthroplasty
frequently show problems during
knee extension exercises due to biomechanical
alterations. Hinged knee prostheses, which
provide higher stability than non-hinged designs,
were supposed to minimize them.
Therefore we investigated the quadriceps force
required to extend the knee after non-hinged and
hinged total knee arthroplasty. Human knee specimens
were tested in a kinematic knee simulator in
physiologic conditions, after implantation of two
types of non-hinged cruciate retaining prosthesis
and a hinged prosthesis. During simulation of an
extension cycle, the change of quadriceps force to
produce the constant extension moment of 31 Nm was
measured using a load cell attached to the
quadriceps tendon. After implantation of the non-
hinged prostheses maximum quadriceps force increased
up to 1257 N in knee extension. Following the
implantation of the hinged prosthesis quadriceps
extension force decreased to 690 N in
extension. Hinged knee prostheses improve the lever
arm in knee extension due to higher knee joint
stability. This would offer a potential advantage
for patients.
frequently show problems during
knee extension exercises due to biomechanical
alterations. Hinged knee prostheses, which
provide higher stability than non-hinged designs,
were supposed to minimize them.
Therefore we investigated the quadriceps force
required to extend the knee after non-hinged and
hinged total knee arthroplasty. Human knee specimens
were tested in a kinematic knee simulator in
physiologic conditions, after implantation of two
types of non-hinged cruciate retaining prosthesis
and a hinged prosthesis. During simulation of an
extension cycle, the change of quadriceps force to
produce the constant extension moment of 31 Nm was
measured using a load cell attached to the
quadriceps tendon. After implantation of the non-
hinged prostheses maximum quadriceps force increased
up to 1257 N in knee extension. Following the
implantation of the hinged prosthesis quadriceps
extension force decreased to 690 N in
extension. Hinged knee prostheses improve the lever
arm in knee extension due to higher knee joint
stability. This would offer a potential advantage
for patients.