Anterior and Posterior Cruciate Ligaments Mechanoreceptors: A Review of Basic Science

Abstract

Proprioception is a specialized sensory modality encompassing the movement of the joint and its position in space, and it involves the conversion of mechanical deformation of tissues into neural signals. Mechanoreceptors are specialized nerve structures able to transmit mechanical deformation through electrical signals to dorsal root ganglion sensory neurons and are abundant in the muscles, tendons and ligaments of the knee joint. They are believed to play an important role in knee proprioception and dynamic knee stability. Proprioception should always be taken into consideration for successful reconstruction of the cruciate-deficient knee and for pain and function management in the arthritic knee. Advances in histological methods of detection are numerous and continue to highlight the presence and role of mechanoreceptors after ligament reconstruction, depending on choice of graft. In this review, we present the current knowledge of anterior and posterior cruciate ligaments and grafts mechanoreceptors, and their role in proprioception of knee joint, focusing on each type of mechanoreceptors.

Posterior cruciate ligament repair seems safe with low failure rates but more high level evidence is needed: a systematic review

“…Firstly, retention of the native ligament. This could be important given the variety of mechanoreceptors that have been identified in the PCL which aid knee stability [ 1 , 32 ]. A recent meta-analysis reported loss of proprioception in PCL deficient knees after PCL reconstruction [ 69 ].…”

Relationship Between Mechanoreceptors in the Posterior Cruciate Ligament and Patient Age or Osteoarthritis Severity

“…The PCL is one of the most important ligaments of the knee joint; it mainly plays a role in preventing the tibia from moving backward relative to the femur and providing knee joint dynamic stability through proprioception and muscle activity. 2 Proprioception includes perception of the static position, displacement, velocity, acceleration, and muscle force of body parts. 3 Proprioception depends on mechanoreceptors, which are distributed in many tissues of the knee joint.…”

Comparison of proprioception recovery following anterior cruciate ligament reconstruction using an artificial graft versus an autograft

“…However, Sha et al used immunohistochemical assays to show that there was no significant quantitative variation in the residual mechanoreceptors throughout the injury duration [ 37 ]. Another study showed that the mechanoreceptors existed in the cruciate ligaments, articular capsule, the lateral structures such as the lateral collateral ligament and the anterolateral ligament, tendons and muscles of the knee [ 8 ]. Trieb et al found that instead of normal ligament tissue 6 months after ACLR with LARS, there were only fibroblasts and some endothelial cells surrounding the ligament fibers [ 38 ].…”

“…Proprioception is the synthesis of the sensory modality of joint movement, joint position, and tactile sense encompassing a joint, whether conscious or unconscious [ 7 ]. Proprioception has been defined as the afferent information arising from the internal peripheral area of the body and contributing to postural control, joint stability, and specific conscious sensations [ 8 ]. The ACL not only provides mechanical stabilization but also contributes to proprioceptive functions, by means of the various mechanoreceptors within its structure, and at the same time, the ACL can detect changes in tension, speed, acceleration, direction of movement, and the position of the knee joint [ 9 , 10 ].…”