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 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.
OBJECTIVE: The review the effect of cytokines on repair of tendon injury and the relevant mechanism. METHODS: By broadly consulting recent issues about cytokines involved in tendon repair, a variety of cytokines with effects in repairing injured tendon was made and the possible mechanisms were summarized, with unsolved problems discussed. RESULTS: There were many cytokines participated in the procedure of tendon repair, among which insulin-like growth factor (IGF-1), transforming growth-beta 1 (TGF-beta 1) played significant roles. Most of the relevant researches were limited in experimental study in vitro. CONCLUSION: Cytokines possibly can accelerate tendon repair and show great potentials in future clinical application.
Because of the complicated causes and variable clinical signs, closed injury of tendons at wrist is difficult to diagnosis and treat. Twenty-six cases of tendon ruptur were reported. Among them, 11 cases were caused by bone fracture or dislocation, 8 cases were caused by rheumatoid synovitis, 5 cases were caused by synovial tuberculosis, and 2 cases caused by other. The pathogenesis and clinical signs were analyzed. Twenty-three cases were treated by tendon transfer and 3 cases were treated by tendon transplantation. By average follow-up of 16 months (ranged 6 months to 4 years), the results were as follows: the clip strength and both active and positive motion of fingers were restored in 19 caese, 75% of those were restored in 7 cases and 50% of those were restored in 2 cases. It was suggested that diagnosis, treatment and function rehabilitation should be carried out early, and tendon transfer or tendon transplatation were the method on priority.
Objective To study the adhesion-preventing effect of basic fibroblast growth factor(bFGF) combined slow-releasing degradable membrane.Methods The bFGF combined slow-releasing degradable membrane was made from bFGF and the reagent which could promote fibrinogen synthesize. Sixty-six SD rats were divided into groups A,B,C randomly (22 rats each group). In group A, sutured achilles tendon were encapsulated with bFGF combined slow-releasing degradable membrane;in group B, sutured achilles tendon were encapsulated with degradable membrane without any drug; in group C, achilles tendon were only sutured. Ninety days later, light-microscope, electronmicroscopoe, figureanalysing, hydroxyproline content, extent of peritendon adhesion and biomechanic test were evaluated.Results ①The amount of fibroblast and fibrinogen inside the sutured tendon in group A was larger than that inits peripheral connective tissue and in groups B and C (P<0.05). Thecontent of hydroxyproline and the ultimate tensile strength in group A was higher than those in groups B and C(P<0.01).② The peripheral tissue in group A almostremains the formal loose connective tissue, but it became dense connective tissue in groups B and C and grew into the tendon. Moreover, the extent of adhesion in group A was lesser than that in groups B, C according to the mensuration of peritendon adhesion.Conclusion The bFGF combined slow-releasing degradable membrane can make the intrinsic healing of tendon faster than peripheral
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 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.
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 evaluate the management of sheath after repair of double tendons in clean-cut injury or severe injury in zone II d. METHODS: Forty-eight white leghorn chickens were divided into 4 groups. Both FDS and FDP tendons in zone II d of long toes were repaired with modified Kessler suture after tendon transection in group A (clean-cut tendon injury, sheath closure), group B (clean-cut tendon injury, sheath excision), group C (severe tendon injury, sheath closure) and group D (severe tendon injury, sheath excision), respectively. Biomechanical studies of gliding excursion and work of flexion were carried out 6 weeks and 12 weeks after tendon repair. The extent of adhesion was examined. RESULTS: After 6 and 12 weeks of repair, there were no significant differences in tendon excursion and work of flexion of the toes between groups A and B. Excursions of FDP tendons in group D was significantly larger than that in group C (P lt; 0.05). Work of flexion and extent of adhesion in group D was significantly less than that in group C (P lt; 0.05). CONCLUSION: The above results indicate that sheath can be closed after repair of both FDS and FDP tendons in clean-cut injury and that sheath should be excised in severe injury in zone II d.