Development of a new suturing technique for tendon graft preparation: an animal cadaver study.

BACKGROUND: This study should analyze ten different suturing techniques for tendon graft preparation to allow the development of an entirely new suturing technique. METHODS: Extensor tendon grafts of fattening bulls' forelegs were sutured with Ethibond Excel size three (six metric) fibers (Ethicon, Somerville, New York, USA). The tendon/suture complexes were biomechanically tested with a hydraulic testing machine applying traction according to a standardized protocol. The testing was observed to find out why the failure at the maximum traction load occurred. The mean values for the maximum tension and extension stiffness were recorded for each suturing technique. FINDINGS: An entirely new suturing technique was developed based on the observations and biomechanical results. The newly developed suture was also tested and provided a higher traction stability than the other ten techniques that had been evaluated. Compared to the other ten techniques the new technique was ranked 3rd in terms of extension stiffness and reached 10.3 N/mm. INTERPRETATION: The new technique evolved in the course of this study provided promising results. Therefore this study provides initial evidence that this technique could be useful in clinical routine.

Impaired tensile strength after shock-wave application in an animal model of tendon calcification.

Extracorporeal shock-wave application facilitates dissolution of rotator cuff calcifications. Therefore, disappearance or disintegration of tendon calcifications by shock waves might be appropriate for any kind of tendon calcification. Here, shock waves with various energy flux densities were applied to the mineralized medial gastrocnemius tendon of turkeys as an animal model. After application of shock waves in vivo, with energy flux density of 0.6 mJ/mm(2), histologic examination and microradiography did not show dissolution or disintegration of tendon calcifications. After shock-wave application in vitro, even for energy flux density of 1.2 mJ/mm(2) neither dissolution nor disintegration of tendon calcifications were observed. Biomechanical testing revealed significant impairment of tensile strength following shock-wave application in vitro, with energy flux density of 1.2 mJ/mm(2), but not with 0.6 mJ/mm(2). These results are important for considerations of clinical extracorporeal shock-wave application on tendon calcifications, as well as on tendon ossifications.

Intrinsic hyperreactivity of mucosal T cells to interleukin-2 in pediatric Crohn's disease.

OBJECTIVES: To cells play a crucial role in many chronic inflammatory diseases. Mucosal T cells are particularly important in the pathogenesis of Crohn's disease (CD). We investigated the response of T cells in CD and other intestinal inflammatory conditions to interleukin-2 (IL-2), a cytokine essential for T-cell activation, growth, and function. STUDY DESIGN: T-cell reactivity was assessed by measuring growth induced by IL-2 in mucosal endoscopic biopsy specimens obtained from children with CD, ulcerative colitis, indeterminate colitis, and chronic nonspecific colitis and from children without gastrointestinal inflammation. RESULTS: CD mucosal T cells grew remarkably and significantly more than T cells from normal, ulcerative colitis, and chronic nonspecific colitis mucosa. T cells from indeterminate colitis mucosa grew similarly to those of CD mucosa. The enhanced growth response in CD was independent of disease location, presence or absence of intestinal inflammation, treatment, disease duration, or clinical activity. CONCLUSION: Mucosal T cells from children with CD exhibit an intrinsic hyperreactivity to IL-2. This may represent a primary pathogenic abnormality in this condition.

Intestinal lymphangiectasia in children: a study of upper gastrointestinal endoscopic biopsies.

From 1980-1986 intestinal mucosal lymphangiectasia was diagnosed histologically in eight patients (6 weeks to 16 years; four males/four females; seven white). The presenting features were diarrhea (six/eight), vomiting (four/eight), and growth deficit (seven/eight). Additional conditions in these patients included asthma, urinary tract infection, esophageal atresia, hydrops fetalis, inflammatory bowel disease, malabsorption syndrome, and thymic hypoplasia. Hypoalbuminemia and edema (four/eight) were more prominent in those patients under 5 years of age. Two had systemic lymphangiectasia and lymphopenia. The patients responded variably to hyperalimentation and dietary supplements, depending on the extent of their lymphangiectasia and the age at onset of symptoms. Dilated lymphatics were seen in the small intestinal mucosa under the surface epithelium. Lesions were often focal, requiring several biopsies or serial sections for detection. Other common findings were mild to moderate lymphoplasmacytic inflammation and mild to moderate villous injury with blunting and edema. Mild inflammation without lymphangiectasia was also present in esophageal, gastric, or colonic biopsies. Diagnosis should be made on the basis of endoscopic findings or in small-intestinal inflammatory conditions even in the absence of a classic clinical picture. Histologic confirmation may require more than one serially sectioned biopsy. This study confirms the diversity of disorders that may be associated with intestinal lymphangiectasia and shows that the disease in infants is more severe and generalized.