Joint Space of the Human Knee and Hip Joint under a Static Load

Abstract

In order to study the joint contact and joint space of statically loaded human knee and hip joints, observations of serial slices of joint specimens which were frozen during the application of a load were carried out. In the intact joints, the articular cartilage surfaces did not come into direct contact with each other even under a load of more than twice that of the body weight. The minimum distance between cartilage surfaces in each specimen ranged from 0.2 to 0.6 mm. The Indian ink whish was injected into the joints before the load application was squeezed out of some areas of the remaining joint space, but a dye-free fluid apparently remained in this space.Based on our findings, the definition of joint contact and the lubrication mechanism in the intact human joint have been discussed.

Arthroscopic acetabular labral reconstruction with rectus femoris tendon autograft: Our experiences and early results

“…This sealing function of the labrum improves the stability of the joint through a vacuum effect and enhances lubrication mechanisms in the hip joint. 3 , 4 The ability of the labrum to contain a pressurised fluid layer within the hip joint under loading conditions prevents direct contact of the joint surfaces and distributed the applied load more evenly across the cartilage surfaces. 1 , 2 With a relatively low permeability, the labrum limit the rate of fluid expression from the cartilage layers during loading.…”

First insights into human acetabular labrum cell metabolism

“…It surrounds and deepens the acetabular rim and serves as a joint seal 3 . This sealing function resists distraction of the femoral head from the socket by acting like a suction cup and maintaining the negative pressure within the joint, thereby improving joint stability 4,5 . The seal also allows for a more uniform distribution of the compressive forces applied to the articular cartilage by maintaining the joint fluid in the central compartment 6e8 .…”

Biotensegrity: What is the big deal?

“…While man-made constructs are engineered to contain shear-stresses within the particular design, it is likely that they would cause material fatigue and collapse if they appeared within developing tissues, and that would really be the end of them (Levin, 1995). Levers also imply that bones must be compressed across their articular surfaces, yet it has been shown that normal joint surfaces in the knee are not compressed, even when they are pushed together (Terayama et al, 1980;Levin and Madden, 2005;Hakkak et al 2015). Current biomechanics does not have a theory to explain how synovial joint surfaces could be held apart, or decompressed, but biotensegrity does and the reader is referred elsewhere for further information (Levin, 2006;Martin, 2016;Scarr, 2018).…”