| Background In recent years,as domestic sports injury further accurate diagnosis and magnetic resonance(NMR),more and more patients with rotator cuff tear especially the supraspinatus tendon tear was diagnosed,rotator cuff tendon repair of massive rotator cuff tear or by way of the most effective treatment in patients with conservative treatment is invalid,but the postoperative rehabilitation in patients with rotator cuff tendon repair need to shoulder joint brake about 1～3 months to make tissue damage or healing(tendon bone healing),so the prevention and treatment of rotator cuff repair postoperative adhesion again for postoperative pain relief and function in patients with rotator cuff injury recovery has the vital role.Chitosan is a chitin polymer compound extracted from the shells of marine shells and crustaceans.It is a medical high-molecular polysaccharide material with good biocompatibility,biodegradability,and biological activity.Its main mechanism for preventing postoperative tissue adhesion is the following:Chitosan has the biological characteristics of selectively promoting the growth of tissue cells but inhibiting the proliferation of fibroblasts,thereby promoting the physiologic repair of tissues,inhibiting the secretion of collagen fibers to form scar tissue,and reducing tissue adhesion;Chitosan has a local hemostatic effect,inhibiting the formation of fibrin bundles,thereby reducing the tissue adhesion caused by the absorption of hematoma;the chitosan has a biological barrier effect and can effectively block the occurrence of adhesion by swelling the surrounding tissue with water swelling.Due to its small toxic and side effects,the material is cheap and easy to obtain.Therefore,in this experiment,medical chitin was used as an experimental drug,and the use of the rabbit rotator cuff as an animal model for postoperative adhesion prevention of rotator cuff tendon injuries was observed from gross anatomy and histological analysis demonstrated the effect of chitosan on preventing adhesions and promoting iliac crest healing.Objective To study the effects of chitosan on tendon-bone healing and tendon adhesion after rotator cuff repair in rabbits.Methods 20 adult healthy New Zealand white rabbits were selected as experimental animals.First of all,the animal model of the rotator cuff injury was set up for all the rabbits,and then the surviving 18 white rabbits were randomly divided into two equal groups:Group A,chitosan treatment;Group B,saline treatment.Two weeks after supraspinatus tenotomy,the rabbits were underwent tendon-bone suture and tendon insertion site reconstruction;then drug experiments were carried out according to grouping.Six weeks after the operation,we used gross anatomy,the adhesion score tests,and histological observation to make a systematic assessment.Results Gross observation:The adhesions of tendon in group A is more slighter than group B at 6 week postoperatively,the difference was significant statistically(H=50.879,P<0.05).Histological observation:Group A showed the overall healing closely resembled the normal rabbit rotator cuff tissue and healed up well,with more marked proliferation of cartilage cells compared with Group B(t=12.408,P<0.05);There were fewer fibroblasts and fibrocytes in the tendon of Group A compared with that in Group B(t= 8.6873,P<0.05);No obvious fatty infiltration was visualized in Group A,whereas fat vacuoles were observed in Group B.Additionally,fibroblast cells were compactly arranged and the direction of arrangement was roughly the same as that of the normal tendon cells in Group A,whereas a disorder of fibroblasts and fibroblasts arranged in Group B.There is a slightly increase in the number of newborn capillaries in Group A compared with that in Group B.Group B than in group A collagen fiber content significantly high(t = 7.34,P<0.05),and the disorder of collagen arrangement,discontinuous phenomenon,group A high content of collagen fiber content than normal rotator cuff,but more similar to normal collagen fiber order.Conclusion Chitosan can improve tendon-bone healing and prevent tendon adhesion following rotator cuff repair in rabbits. |
