Mixture of hyaluronic acid and phospholipid prevents adhesion formation on the injured flexor tendon in rabbits

Abstract

Dipalmitoyl phosphatidylcholine, a highly surface-active polar lipid, has been implicated as a potential boundary lubricant for synovial joints. We examined the effects of dipalmitoyl phosphatidylcholine on the flexor tendon and its protective effect against postoperative adhesion in two experimental steps. First, the flexor digitorum fibularis and the distal pulley of rabbits were set for a friction test. The test was performed with saline solution, sodium hyaluronate, or a mixture of dipalmitoyl phosphatidylcholine and sodium hyaluronate as the lubricant. The friction coefficient was significantly lower with the mixture of dipalmitoyl phosphatidylcholine and sodium hyaluronate than with saline solution or sodium hyaluronate. We concluded that the decreased friction coefficient indicates that dipalmitoyl phosphatidylcholine could complement the boundary-lubricating ability of the tendon. In the second experiment, we used an experimental adhesion model of the flexor digitorum fibularis in the rabbit. During the operation, either saline solution, sodium hyaluronate, or a mixture of dipalmitoyl phosphatidylcholine and sodium hyaluronate was injected into the tendon sheath. The specimen was sent to another tester, and the work required to tear off the adhesion was measured. The work required was significantly greater for the tendons that had been injected with saline solution than for those given injections of dipalmitoyl phosphatidylcholine and sodium hyaluronate. Our findings suggest that dipalmitoyl phosphatidylcholine plays an important role in the boundary lubrication of the tendon and that after tendon injury, the administration of a mixture of dipalmitoyl phosphatidylcholine and sodium hyaluronate may improve tendon lubrication and prevent adhesion formation.

CORR® ORS Richard A. Brand Award for Outstanding Orthopaedic Research: Engineering Flexor Tendon Repair With Lubricant, Cells, and Cytokines in a Canine Model

“…Second, we did not test either the cell-based therapy or surface modification alone. However, some studies have shown that bone marrow stromal cells do increase tendon healing capacity [8,10,15], and others have shown that surface modification decreases tendon adhesions [14,40]. Therefore, the purposes of our study were to investigate the effects of combining these treatments on postoperative adhesion formation and tendon healing.…”

Surface Modification with Chemically Modified Synovial Fluid for Flexor Tendon Reconstruction in a Canine Model in Vivo

“…In previous studies, we found that surface modification with carbodiimide-derivatized HA combined with lubricin (cd-HA-lubricin) greatly reduced tendon adhesion and improved digital function but also adversely affected tendon healing 20,21 . In addition to HA and lubricin, phospholipids also have been found to decrease tendon gliding resistance and improve outcomes after flexor tendon repair 22 . All three lubricating molecules are native components of synovial fluid and are found on the intrasynovial tendon surface [23][24][25] .…”

Biomechanical Testing of Orthopedic Implants; Aspects of Tribology and Simulation

“…The polysaccharide hyaluronic acid (HA) is the main component of the joint fluid. It is produced by the synovial membrane and forms a high molecular mass complex [16,17]. Both aging and arthritis can reduce both the concentration and the relative molecular weight of HA, and thus reduce the viscosity of the synovial fluid.…”

“…The work (force × distance) becomes an important parameter for estimating the adhesion formation on the injured flexor tendon that cannot withstand the reciprocating motions of a pendulum test [17].…”