The attachment of intrinsic and extrinsic, mobilized and immobilized adhesion cells to collagen and fibronectin

[Application of medical biomaterials in prevention and treatment of tendon adhesion]

OBJECTIVE

To review the research progress of medicine biomaterials in prevention and treatment of adhesion after tendon injury, and to provide reference for clinical treatment.

METHODS

The literature on the application of medical biomaterials in the prevention and treatment of tendon adhesions in recent years was reviewed, and the biological process, treatment methods, and current status of tendon adhesions were summarized.

RESULTS

Tendon adhesion as part of the healing process of the tendon is the biological response of the tendon to the injury and is also a common complication of joint dysfunction. Application of medical biomaterials can achieve better biological function of postoperative tendon by reducing the adhesion of peritendon tissues as far as possible without adversely affecting the tendon healing process.

CONCLUSION

The use of medical biomaterials is conducive to reduce the adhesion of tendon after operation, and the appropriate anti-adhesion material should be selected according to the patients' condition and surgical needs.

Effect of Acellular Amnion With Increased TGF-β and bFGF Levels on the Biological Behavior of Tenocytes

The human amniotic membrane has been a subject for clinical and basic research for nearly 100 years, but weak rejection has been reported. The purpose of this research is to remove the cellular components of the amnion for eliminating its immune-inducing activity to the utmost extent. The amniotic membrane treated by acid removed the epithelial cell, fibroblast, and sponge layers and retained only the basal and dense layers. In vitro, biological effects of the new material on tenocytes were evaluated. The levels of transforming growth factor (TGF-β1), fibroblast growth factor (bFGF) proteins were measured. In vivo, the tendon injury model of chickens was constructed to observe effects on tendon adhesion and healing. The acellular amniotic membrane effectively removed the cell components of the amnion while retaining the fibrous reticular structure. Abundant collagen fibers enhanced the tensile strength of amnion, and a 3D porous structure provided enough 3D space structure for tenocyte growth. In vitro, acellular amnion resulted in the fast proliferation trend for tenocytes with relatively static properties by releasing TGF-β1 and bFGF. In vivo, the experiment revealed the mechanism of acellular amnion in promoting endogenous healing and barrier exogenous healing by evaluating tendon adhesion, biomechanical testing, and labeling fibroblasts/tendon cells and monocytes/macrophages with vimentin and CD68. The acellular amnion promotes endogenous healing and barrier exogenous healing by releasing the growth factors such as TGF-β1 and bFGF, thereby providing a new direction for the prevention and treatment of tendon adhesion.

The effects of 5-fluorouracil on flexor tendon healing by using a biodegradable gelatin, slow releasing system: experimental study in a hen model

This study investigated the effects of 5-fluorouracil in a slow-release biodegradable gelatin system on tendon healing. Gelatin blocks prepared in a size of 10 × 20 × 1 mm were loaded with 10, 20, and 30 mg of 5-fluorouracil, and 30 adult white Leghorn chickens were used. The tendons to the third and fourth toes were severed and repaired. The extremities were casted for three weeks. After sacrifice, the tendons were examined histologically and biomechanically for adhesion formation. The 10 mg-loaded gelatin group showed a decrease in adhesion formation when compared with the operative control group; the 20 and 30 mg groups showed signs of severe inflammation. Low doses of 5-fluorouracil applied via a slow-release gelatin system reduced adhesion formation in flexor tendon healing.