In order to compare the immunogenecity and biological properties of homologous tendon grafts after treatment from different methods of freezing, tendons from chickens received repeated freezing-thawing treatment or ultra-low-temperature treatment, and then, the post-treatment tendons were preserved in liquid nitrogen for 3 months before transplantation. The autogenous tendon transplantation was served as the control. It was found that in the group of repeated freezing-thawing treated tendons, the tendon cells all died and while in the ultra-low temperature treated tendons the active rate of tendon cells was 92.5% +/- 3.4%, and the histological observation showed that transplantation of frozen tendons would result in extensive infiltration of inflammatory cells in the grafted tendons and the peritendinous adhesion was serious than that of the autografts. The active flexion function, hydroxyproline levels and the biomechanical analysis showed no significant differences between the repeated freezing-thawing treated homografts and the ultra-low-temperature treated homografts, and that the autografts was definitely superior to the homografts. The conclusions were: (1) Transplantation of the homologous tendons from the two different methods of freezing could receive considerable success and there was no significant difference between them; (2) Transplantation of frozen homologous tendon graft might give successful result which was probably due to the preservation of the cellular activity of the tendon cells following freezing treatment and elimination of the antigen presenting cells in the tendon as well, and (3) Although the cellular components of the tendon were damaged and the antigenicity of the tendon was lowered, it did not necessarily mean that homologous tendon graft would always be successful in transplantation.
In order to understand the influence of the free tendon graft and the tendon transfer on their blood supply, histological and biochemical changes during healing following repair of the damaged tendon after the alteration of the nourishing environment, an experiment was carried on 36 New Zealand white rabbits. In the front paws of the rabbits, the free tendon graft was sutured in the tendon defect of flexor of the fourth toe and the flexor tendon of the third toe was transferred to the second toe to reconstr...
In order to study the influence of severity of tendon injury on the morphology of collagen fibers during healing process of extensor tendons, 40 female Wistal rats were used for investigation. The rats were divided into 2 groups. Transection of the tendon of extensor digitorum longus was performed in one group, while partial section of the same tendon was performed in the other group. Morphometric analysis was undertaken on the 15th, 30th, 60th and 90th day after operation. The result was that there was no significant difference between the two groups both in distribution and diameter of collagen fibers on the 15th and 30th days (P gt; 0.05). However, there was significent difference between those on the 60th and 90th days (P lt; 0.05). It was concluded that the severity of the tendon injury could influence the morphology of collagen fibers during the late stage of tendon healing.
OBJECTIVE: To investigate the influence of tissue engineered tendon on subgroup of T lymphocytes and its receptor in Roman chickens. METHODS: The flexor digitorum profundus of the third toes of right feet in 75 Roman chickens were resected and made 2.5 cm defects as experimental model. They were randomly divided into five groups according to five repair methods: no operation (group A), autograft (group B), fresh allograft (group C), polymer combined with allogenous tendon cells (group D), derived tendon materials combined with allogenous tendon cells (group E). The proliferation and transformation of lymphocytes and contribution of CD4+, CD8+, CD28 and T cell receptor (TCR) were detected to study the immune response. RESULTS: The CD4+, CD8+ and TCR of group D and E were increased slightly than that of group B after 7 days, while after 14 days, those data decreased gradually and no significant difference between tissue engineered tendon and autografts (P gt; 0.05), and there was significant difference between fresh allograft and tissue engineered tendon (P lt; 0.05). Lymphocytes transformation induced by conA also showed no significant difference between tissue engineered tendon and autografts (P gt; 0.05). CONCLUSION: Tendon cells are hypoantigen cells, there are less secretion of soluble antigen or antigen chips dropped out from cells. Tissue engineered tendon has excellent biocompatibility.
A comparative study was given to a group of grafted tendons on rabbits either with complete immobilization or early controlled passive mobilization of the affected parts immediately following operation. In the study, the healing mechanism, adhesion formation and breaking strength at the grafted site of the tendons were included. The results showed that early controlled passive mobilization had no influence on the survival and its healing process, but the adhesion surrounding tendons would be looser and the vessels on the surface, of the grafted tendons would be orientated longitudinally enhancing tendon gliding promoted collagen it would also promote collagen production and thus increased the rupturing strength at the grafted site.
Objective To review the research and del ivery methods of growth factors in tendon injuries, and to point out the problems at present as well as to predict the trend of development in this field. Methods Domestic and international l iterature concerning growth factors to enhance tendon and l igament heal ing in recent years was extensively reviewed and thoroughly analyzed. Results Cell growth factor could promote tendon heal ing, improve the mechanical properties as well as reduce the adhesion postoperatively. The use of transgenic technology mediating cell factors to promote tendon repair shows its advantages in many ways. Conclusion The growth factors play a vital role in tendon heal ing. Reasonable treatment of growth factors through direct appl ication or gene transfer techniques is of great value for the heal ing process.
Through dissection of 12 fresh finger specimens, the anatomy of the distal part of dorsal aponeurosis and its function was closely observed. A direct reparative procedure of the terminal tendon by using tendon flap graft was deseribed for the treatment of chronic mallet finger deformity. Correction of deformity, restoration of active motion of DIP and avoidance of residual pain were observed in three clinical cases.
OBJECTIVE To improve the clinical result of repair on flexor tendon injury, and recover the defected finger function in children as far as possible. METHODS From January 1990 to October 1997, 12 cases with flexor tendon injury were repaired by microsurgical technique, sutured by modified Kessler method with 3/0 or 5/0 nontraumatic thread and followed by invering suture of the gap edge with 7/0 or 8/0 nontraumatic thread after debridement. Appropriate functional practice was performed postoperatively. RESULTS All the defected fingers were healed by first intention. Followed up 6 months to 1 year, there was excellent in 7 cases, better in 4 cases, moderate in 1 case and 91.67% in excellent rate according to the TAM standard of International Hand Committee. CONCLUSION The important measures to improve the clinical result in children’s flexor tendon injury are prompt and accurate diagnosis and repair of the injured tendon by microsurgical technique, and effective postoperative functional practice.
Flexion tendons in fibrous sheath of 36 New Zealand white rabbits was repaired, after excision of fibrous sheath and vinculum, with microsurgical technique. Histological examination was made. The results showed that as the prolongation of the postoperative time, the adhesion around the tendon became more and more dense. 7 days after operation, tendon was connected by hemocyte and fibroid materials. Following 7 days after operation, fibroblaste origined from extrinsic memberance of tendon obviously produced,and strentched to tendon stump. The synthesis of collage fibers began at 21 days after operation .28 days,connective tissure between tendon stumps was tendency of reconstruction. The experiment demonstrated that pattern of tendon healing belinged to extrinsic repair . That was related to destroy of tendon nutrition systems in fibrous sheath.
Objective To investigate the effects of human acellularamnion membrane on SD rat tendon adhesion and to obtain the experimental data for clinical application in preventing postoperative tendon adhesion. Methods The tendons of 28 adult SD rats hindlimb were cut and sutured. The tendons of left hindlimb were encapsulated by human accellular amnion membraneas the experimental group and the ones of the other side were not encapsulatedas control group. The rats were killed 1, 2, 4, 6, 8 and 12 weeks after operation. The results were evaluated grossly and histologically. Results There were no differences in healing of injury tendon and inflammatory response between the two groups. The anatomical and histological results showed the experimental group had less adhesion than the control group(Plt;0.05). Conclusion Human acellular amnion membrane can prevent adhesion of tendonwithout affecting tendon healing and is an optimal biological material to prevent tendon adhesion.