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 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.
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 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.
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.
This paper reported the method tendon reconstruction on dogs. Using the pedicled fascio-tendon graft, the flexor tendon system was constructed, and comparative study was made between the vascularized fascio-tendon graft and the free fascio-tendon graft by means of oxygen tension measurement, stereology, histology and ultra-mieroseoppy. The results showed: 1. vascularized graft changed the course of healing of the conventional graft into a simplified tendon stump healing course which shortened the healing time, ahd reduced the formation of peritendinous.2. the fascia tissue could be transformed into the synovial-like tissue6 weeks postopertively under the stimulation of gliding pressure of the tendon.It was conclude that this was a new and better method in reconstructing the severely damaged flexor tendon system.
Objective To investigate the cellular compatibil ity of polyvinyl alcohol (PVA)/wild antheraea pernyisilk fibroin (WSF), and to explore the feasibil ity for tendon tissue engineering scaffold in vitro. Methods The solutions of WSF (11%), PVA (11%), and PVA/WSF (11%) were prepared with 98% formic acid (mass fraction) at a mass ratio of 9 : 1. The electrospinning membranes of WSF, PVA, and PVA/WSF were prepared by electrostatic spinning apparatus. The morphologies of scaffolds were evaluated using scanning electronic microscope (SEM). The tendon cells were isolated from tail tendon of 3-dayold Sprague Dawley rats in vitro. The experiment was performed using the 3rd generation cells. The tendon cells (1 × 106/mL) were cocultured with PVA and PVA/WSF electrospinning film, respectively, and MTT test was used to assess the cell adhesion rate 4, 12 hours after coculture. The tendon cells were cultured in PVA and PVA/WSF extraction medium of different concentration (1, 1/2, and 1/4), respectively; and the absorbance (A) values were detected at 1, 3, 5, and 7 days to evaluate the cytotoxicity. The composite of tendon cells and the PVA or PVA/WSF scaffold were observed by HE staining at 7 days and characterized by SEM at 1,3, 5, and 7 days. Results The solution of WSF could not be used to electrospin; and the solution of PVA and PVA/WSF could be electrospun. After coculture of tendon and PVA or PVA/WSF electrospinning membranes, the cell adhesion rates were 26.9% ±0.4% and 87.0% ± 1.0%, respectively for 4 hours, showing significant difference (t=100.400, P=0.000); the cell adhesion rates were 35.2% ± 0.6% and 110.0% ± 1.7%, respectively for 12 hours, showing significant difference (t=42.500, P=0.000). The cytotoxicity of PVA/WSF was less significantly than that of PVA (P lt; 0.05) and significant difference was observed between 1/2 PVA and 1/4PVA (P lt; 0.05). HE staining and SEM images showed that the tendon cells could adhere to PVA and PVA/WSF scaffolds, but that the cells grew better in PVA/WSF scaffold than in PVA scaffold in vitro. Conclusion PVA/WSF electrospinning membrane scaffold has good cell compatibility, and it is expected to be an ideal scaffold of tendon tissue engineering.
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.
To design a new suit of instruments for meniscal suture with tondon, and then authenticate their feasibil ity and the therapeutic effect of the new technique. Methods Instruments were developed, including new ones and others which was improved according to the current instruments. From October 2005 to December 2006, 45 patients with meniscal injury were treated by meniscal suture with tendon. There were 29 males and 16 females, aged 17-40 years (mean 28 years). Injury was caused by sports in 33 cases, by traffic accident in 5 cases, by fall ing in 3 case and others in 4 cases. The disease course was 3 days to 6 months (mean 2 months). There were 23 cases accompanying with anterior cruciate l igament injury and 6 cases accompanying with posterior cruciate l igament injury. E-MRI showed 2 cases of degree II and 43 cases of degree III. Arthroscope showed that injury was at medial meniscus in 39 cases and at lateral meniscus in 6 cases. The pre-operationalLysholm score was 53.0 ± 10.3. Autogeneic or xenogenic tendon was made into suture l ine guided by stitch at the two ends. Thetherapeutic effect of the new technique was authenticated by cl inical results, including the change of symptoms and phy sical signs, and by comparing the pre-operational Lysholm score with the post one. Results Nineteen pieces of instruments weredeveloped. All the operation were successful, with no harm to nerves and vessels. The follow-up was 6 months to 24 mo nths (mean15 months). At the last follow-up, all the symptoms disappeared, including pain, swell ing and locking, etc. The Lysholm sc oreafter 6 months of operation was 87.8 ± 9.2, showing statistically significant difference when compared with per-operati on ( P lt; 0.01). Conclusion It is feasible to suture injured menisci with the new instruments and technique. It is an effective way to repair menisci with tendon according to the short-term results.
Objective To explore the clinical application of allogeneic tendonhandled by ultra-deep-low-temperature. Methods From March 1995 to June 2002，tendons rupture and tendons defect were repaired by ultra-deep-low-temperatureallogeneic tendon grafts in 96 cases, including 51 cases of flexor or extensor tendon defect of hand, 36 cases of coracoclariculare ligament rupture, 4 cases of cruciate ligament rupture, 2 cases of calcaneus tendon rupture and 3 cases ofextensor tendon defect of foot. The interval between injury and operation was 1day to 5 months. The length of defect was 4-12 cm with an average of 7 cm.The matching allogeneic tendons were selected during operation, and early function exercise was done after operation. Secondary release was performed in the cases of tendon adhesion.Results Follow-up time is from 6 months to 5 years (3.4 years on average). No rejection or rupture occurred after tendon allograft. The satisfactory result was achieved in 92.71% of the cases. Conclusion The allogeneic tendon is similar to auto-tendon in transplanting, healing and function is useful clinically.