The reconstruction of the extension function of wrist and fingers in 35 patients with radial nerveinjury was reported, The indications of oporation and the main management during and after operationwere discussed.It was thought that the tendon transfer was an effective method to reconstructextension functions of wrist and fingers after the injury of radial nerves and could be served as asupplementary means after radial nerve repair.
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
Objective Platelet-rich plasma (PRP) secretes many growth factors, including transforming growth factor β1 (TGF-β1), platelet derived growth factor, vascular endothl ial growth factor, insul in-l ike growth factor 1, and so on, which can promote cell prol iferation, chemotaxis, and collagen synthesis in wound heal ing. To investigate the effects of PRPon the tendon heal ing, and to explore the mechanism of action so as to provide the experimental basis for the tissue engineered tendons. Methods Forty healthy New Zealand white rabbits, weighing 2.5-3.0 kg and male or female, were randomly divided into the experimental group (n=20) and the control group (n=20). PRP was prepared from arterial blood of rabbit’s ears through twice centrifugation method of Landesberg. The platelet concentrations of whole blood and PRP were determined. The right achilles tendons of the rabbits were transected to make rupture models. In experimental group, the tendon was sutured after PRP (0.5 mL) was immediately appl ied at repair site. In control group, the tendon was sutured directly after transection. At 1, 2, 4, and 6 weeks after operation, the tendons of 5 rabbits in each group were harvested for morphological, histological, and immunohistochemical observations; the fibroblast counting, the content of collagen fibers, and the expression of TGF-β1 were detected. Results The concentration of platelet of PRP was 4.03 times of whole blood. All the animals survived till the end of the experiment, and the incision healed well. No death, infection, and other compl ications occurred. With time, the tendons almost healed in 2 groups, and the fibrous tissue at anastomosis site was more remarkable in control group than in experimental group. The histological observation showed significant differences in fibroblast counting at 1, 2, and 4 weeks after operation between 2 groups (P lt; 0.05), while no significant difference at 6 weeks (P gt; 0.05). The contents of collagen fibers in the parenchyma at repair site in experimental group were significantly higher than those in control group at each time point (P lt; 0.05). Immunohistochemistry staining showed the expression of TGF-β1 in experimental group was upregulated at 1 week and 2 weeks and reached the peak at the 2nd week, and subsequently downregulated at 4 and 6 weeks in comparison with the control group, showing signficant differences between 2 groups at each time point (P lt; 0.05). Conclusion PRP can facil itate rabbit’ s tendons heal ing and significantly improve the heal ing qual ity, which may be associated with its advancing the peak time of the TGF-β1 expression in tendon.
【Abstract】 Objective To compare the therapeutic effect of anterior cruciate l igament (ACL) reconstruction bymeans of four-strand semitendinosus tendon autograft and l igament advanced reinforcement system (LARS) by arthroscopy. Methods From July 2002 to April 2005, 42 patients underwent ACL reconstruction by arthroscopy. Twenty-seven patients were treated by four-strand semitendinosus tendon autograft (semitendinosus tendon autograft group), including 22 males and 5 females, with the age from 20 years to 52 years. Among these patients, there were 12 sports injuries, 8 traffic accidents and 7 other injuries. There were 16 cases of left knees and 11 of right knees. The pre-operation Lysholm score was 50.70 ± 6.68, and the course of the disease was 2 to 12 months. Other 15 patients were treated by LARS artificial l igament (LARS group), including 12 males and 3 females, with the age from 17 years to 40 years. Among these patients, there were 8 sports injuries, 4 traffic accidents and 3 other injuries. There were 6 cases of left knees and 9 of right knees. The pre-operation Lysholm score was 50.20 ± 6.22, and the course of the disease was 3 to 12 months. There was no statistically significant difference between the two groups (P gt; 0.05). The ranges of motion, stabil ity and compl ication of the knee were evaluated during the follow-up. Results All incisions healed at the first stage. The patients in the semitendinosus tendon autograft group were followed up for 22 months to 43 months, while 18 months to 40 months in the LARS group. There were 5 patients (19%) whose tensile gap was more than3 mm when the max tensile force text was done in the semitendinosus tendon autograft group, and 3 patients (20%) in the LARS group. The Lysholm score was 87.80 ± 3.41 in the semitendinosus tendon autograft autograft group, and 88.90 ± 3.30 in the LARS group. There was no statistically significant difference between the two groups (P gt; 0.05). The final evaluation based on the improved Lysholm classification standard showed the choiceness rate was 92.6% (18 excellent cases, 7 good cases and 2 faircases) in the semitendinosus tendon autograft group, and 93.3% (11 excellent cases, 3 good cases, 1 fair case) in the LARS group. There was no statistically significant difference between the two groups (P gt; 0.05). The joint motion capabil ity evaluation, according to the Tegner standard, showed 3 to 6 class (with the average class of 4.93) in the semitendinosus tendon autograft group, and 3 to 7 class (with the average class of 5.03) in the LARS group. There was no statistically significant difference (P gt; 0.05). The knee extension in 2 cases was 5° less than the normal, and in 5 cases 5-10° less than the normal in the semitendinosus tendon autograft group. But in all cases in the LARS group, joint motion recovered to the normal (P lt; 0.05). There was no sign of synovitis in both groups. Conclusion The recent cl inical result of ACL reconstruction with the four-strand semitendinosus tendon autograft or LARS artificial l igament by arthroscopy is satisfactory without significant difference. LARS can shorten the recovery time without compl ications such as synovitis in 2-year follow-up.
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.
This paper reviewed the main achievements in the research on tissue engineering tendon, focusing on major problems concerning the substitute for extracellular matrix (ECM) of tendon, biological characteristics of tendon cells, and tendon cells compounding with ECM substitute. It was concluded the important problems in the study of the tissue engineering having specific reparative functions could be: to prepare the ECM materials suitable for the tendon cells to attach, grow, and function; to establish the tendon cell line whose growth, proliferation, and immunological antigenicity could be modulated and controlled, and simulating the mechanical environment of tendon in vivo, to adopt three-dimensional tendon cell culture method.
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.
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 possibility of repairing defected tendon with a tissue engineering tendon, combined culture of allogenous tenocyte and derived tendon. Methods Macaca tenocytes labelled by BrdU were seeded on the derived tendon. The flexor digitorum profundus of five fingers of left hand in 15 Macaca mulatta were resected and made 2.5cm defects as experimental model. They were divided into three groups according to repair methods (Group A: Combined culture of derived tendon materials and alloggenous tendon cells; Group B; Derived tendon materials; Group C; Autograft). In different stages, the labeled BrdU of tendon cells were observed. Results In Groupo A, after iin vivo implantation, the tenocytes could proliferate and synthesize collagen; the new tissue was white and glossy and the collagen fibers fused to form dense tendon structure as several weeks passed. Twelve weeks after implantation, the tenocytes still survived and synthesized collagen, the results of labelled cells were positive by immunothistochemical methods. By scanning electron microscopic observation, the tenocytes arraged regularly and evely among the derived tendon; the collagen fibers formed a network and its main direction was accord with that of the derived tendon. Normal nucleus, nucleolus, and cell organelles were seen under transmission electron microscope. Conclusion Combined culture of tenocytes with derived tendon is able to make tendon like tissue. The structure of tissue engineering tendon in similar to that of normal tendon.
Objective To introduce the effect of platelet-rich plasma (PRP) in the treatment of chronic tissue lesions. Methods The latest research papers concerning the relevant subject were reviewed and analyzed. Results In PRP, the platelets and cytokines, the interaction of them in the same proportion as they were in the body fluid, played promoting role in repairing the chronic damage of tissues. However, there was still way to go before PRP was appl ied for cl inical use in a widerrange. Conclusion PRP has quite a bright outlook in the treatment of chronic tissue lesions.