Biomedical subjects

Ioannis K Triantafillopoulos

Publications and source records attributed to Ioannis K Triantafillopoulos.

4 recordsLinked to original sources

PubMed2004

Nandrolone decanoate and load increase remodeling and strength in human supraspinatus bioartificial tendons.

BACKGROUND: To date, no studies document the effect of anabolic steroids on rotator cuff tendons. STUDY DESIGN: Controlled laboratory study. HYPOTHESIS: Anabolic steroids enhance remodeling and improve the biomechanical properties of bioartificially engineered human supraspinatus tendons. METHODS: Bioartificial tendons were treated with either nandrolone decanoate (nonload, steroid, n = 18), loading (load, nonsteroid, n = 18), or both (load, steroid, n = 18). A control group received no treatment (nonload, nonsteroid [NLNS], n = 18). Bioartificial tendons' remodeling was assessed by daily scanning, cytoskeletal organization by staining, matrix metalloproteinase-3 levels by ELISA assay, and biomechanical properties by load-to-failure testing. RESULTS: The load, steroid group showed the greatest remodeling and the best organized actin cytoskeleton. Matrix metallo-proteinase-3 levels in the load, steroid group were greater than those of the nonload, nonsteroid group (P <.05). Ultimate stress and ultimate strain in the load, steroid group were greater than those of the nonload, nonsteroid and nonload, steroid groups (P <.05). The strain energy density in the load, steroid group was greater when compared to other groups (P <.05). CONCLUSIONS: Nandrolone decanoate and load acted synergistically to increase matrix remodeling and biomechanical properties of bioartificial tendons. CLINICAL RELEVANCE: Data suggest anabolic steroids may enhance production of bioartificial tendons and rotator cuff tendon healing in vitro. More research is necessary before such clinical use is recommended.

Adult↗

PubMed2004

Thermal microdebridement does not affect the time zero biomechanical properties of human patellar tendons.

BACKGROUND: Thermal microdebridement for the treatment of chronic tendinopathy has recently been introduced. The effect of thermal microdebridement on the biomechanical properties of human tendons, however, remains unknown. HYPOTHESIS: Thermal microdebridement does not affect the biomechanical properties of human patellar tendons in a cadaveric model at the time of initial treatment. STUDY DESIGN: Controlled laboratory study. METHODS: The central 15 mm of 12 matched, human (mean age, 71 years; 8 male, 4 female), fresh-frozen patellar tendons was divided into 3 equal 5-mm specimens. The treatment group (n = 12) underwent thermal microdebridement with a radiofrequency probe. A sham treatment group (n = 12) underwent insertion of a deactivated probe. The control group (n = 12) underwent no treatment. After treatment, each specimen was tested to failure in a servo-hydraulic materials testing machine at an elongation rate of 3 mm/s. One-way repeated measures analysis of variance was used to determine differences between groups. RESULTS: No significant difference in ultimate stress at failure, elastic modulus, strain energy density, or strain at maximum load was found between the groups. The ultimate stress at failure for the treatment, sham, and control groups was 61.0, 66.7, and 63.0 MPa, respectively (P = .653), and the strain at maximum load was 0.12, 0.11, and 0.09, respectively (P = .279). CONCLUSIONS: Thermal microdebridement does not affect the biomechanical properties of cadaveric human patellar tendons at the time of initial treatment. CLINICAL RELEVANCE: It may be safe to proceed with aggressive rehabilitation after thermal microdebridement of the patellar tendon. However, the results in this cadaveric model should be interpreted with caution. Additional studies using an in vivo model will be required to completely assess the effects of thermal microdebridement on the biomechanical properties of human patellar tendons.

Aged↗

PubMed2003

Avulsion fractures of the tibial tuberosity in adolescent athletes treated by internal fixation and tension band wiring.

Avulsion of the tibial tuberosity is a rarely reported fracture. It is mainly considered as an athletic injury accounting for less than 3% of all epiphyseal lesions. In this study, we hypothesized that the use of tension band wiring as a supplement of the internal fixation for the avulsion fractures of the tibial tuberosity would lead the adolescent athletes to a more effective rehabilitation program and an earlier resumption of their previous activity level. Ten patients were treated in our department over a period of 11 years (1985-1995). Operative treatment was thought necessary for all our cases due to tibial tuberosity displacement. Open reduction and internal fixation in combination with tension band wiring was used. The result in all cases was that the reduction was maintained intact and the fracture united. The functional results were excellent, and all patients returned to their previous athletic activities. Our conclusion is that the combination of internal fixation and tension band wiring for avulsion fractures of the tibial tuberosity seems to be more effective and advantageous than conservative or other surgical methods. Avoiding the need of external support and allowing early joint motion, the method described prevents serious quadriceps atrophy, allowing the young athletes to return earlier to their previous sport activities.

Adolescent↗

PubMed2001

Articular changes in experimentally induced patellar trauma.

Only a few studies have described the microscopic pathology of the articular cartilage after trauma. In the present animal study, we demonstrate the effect of trauma on the articular cartilage of the patella and determine the histological changes. Traumatic injury of the patella was experimentally induced in 45 white New Zealand rabbits aged 4 to 6 months old. The articular cartilage of the patella was observed after the sacrifice of the animals immediately and at days 1, 2, 4, 8, and 15 as well as at months 1, 2 and 3 after the traumatic injury. Macroscopic, light and electron microscopic findings showed progressive articular cartilage changes with failed effort of cartilage repair. Osteoarthritic-like degeneration of the articular cartilage was found in all specimens. According to this experimental study, trauma to the articular cartilage may progress to arthritis. The reversibility of cartilage damage or the progression to arthritis seem to be associated with many factors such as the intensity and frequency of the trauma, the mechanism of injury, the intrinsic remodeling of the cartilage matrix and the capability of the articular cartilage to regenerate.

Animals↗