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.
The purpose of this study was to compare the measurement of several anatomical features of the medial patellofemoral ligament (MPFL) between magnetic resonance imaging (MRI) and by direct fashion during dissection. We hypothesized that the measurements between these two techniques would agree. MRI of 30 fresh-frozen cadaveric knees was followed by dissection. MPFL patella and femoral attachment were evaluated; their shape, length, and width were measured; and measurements were compared. MRI was deemed unreliable for the determination of several of the aforementioned anatomical features. Important findings include: (a) observations on MPFL attachment at medial patella side and attachment to quadriceps were identical between dissection and MRI; (b) average width at patella insertion was significantly different between the two methods (p = 0.002); and (c) an attachment to the quadriceps tendon was present in 20/30 specimens and d. detailed measurements of a thin, non-linear, and three-dimensional structure, such as the MPFL, cannot be performed on MRI, due to technical difficulties. This anatomical radiological study highlights the shape, anatomical measurements (length and width), and attachment of the MPFL using a relatively large cadaveric sample and suggests that MRI is not reliable for detailed imaging of its three-dimensional anatomy.
We completed an anatomic cadaver study in order to examine the arterial supply around the knee and to create useful images regarding the arterial surgical anatomy around the knee. A total of four unmatched fresh-frozen cadaveric knees were utilized. There was no medical history of osteoporosis, bony or soft-tissue injury or surgery in any of the knees. The femoral arteries were cannulated with a large catheter at the proximal aspect of the cadavers, and liquid latex in different colours was injected. Τhe specimens were then placed into a bath of 8.0% sodium hypochlorite to complete debridement of the soft tissues to various degrees. The specimens were checked every 15 to 30 min until adequate debridement occurred, and photographs were taken during each stage of this process. Sodium hypochlorite, among others, chemically debrides the vessel walls leaving the casts of the vessel lumens filled with solid coloured latex in order to illustrate the vascular supply pattern to the structures of interest. Knowing the probability of where these arteries should be located adds to the knowledge that surgeons have at their disposal when performing procedures involving arthroscopy, arthroplasty and osteotomies, which can help decrease unnecessary damage to the arteries.