       Document 0005
 DOCN  M9630005
 TI    Gamma irradiation: effects on biomechanical properties of human
       bone-patellar tendon-bone allografts.
 DT    9603
 AU    Fideler BM; Vangsness CT Jr; Lu B; Orlando C; Moore T; Department of
       Orthopaedic Surgery, University of Southern; California School of
       Medicine, Los Angeles 90033, USA.
 SO    Am J Sports Med. 1995 Sep-Oct;23(5):643-6. Unique Identifier : AIDSLINE
       MED/96089278
 AB    Sixty 10-mm bone-patellar tendon-bone allografts from young human donors
       were placed into four test groups, a control fresh-frozen group and
       three fresh-frozen irradiated groups. The irradiated groups were exposed
       to 2.0, 3.0, or 4.0 Mrad of gamma irradiation. The specimens were tested
       to tensile failure. The initial biomechanical strength of fresh-frozen
       allografts was reduced up to 15% when compared with fresh-frozen
       controls after 2.0 Mrad of irradiation. Maximum force, strain energy,
       modulus, and maximum stress demonstrated a statistically significant
       reduction after 2.0 Mrad of irradiation (P < 0.01). Stiffness,
       elongation, and strain were reduced but not with statistical
       significance. A 10% to 24% and 19% to 46% reduction in all biomechanical
       properties were found after 3.0 (P < 0.005) and 4.0 (P < 0.0005) Mrad of
       irradiation, respectively. After irradiation with a 4.0 Mrad dose, the
       ultimate load was below that of reported values for the human anterior
       cruciate ligament. It is clinically important to observe and document
       changes in human ligaments that result from currently used doses of
       gamma irradiation. The results from this study provide important
       information regarding the initial biomechanical properties of
       fresh-frozen human bone-patellar tendon-bone allografts after bacterial
       sterilization with gamma irradiation. The current accepted dose for
       sterilization is between 1.5 and 2.5 Mrad. There appeared to be a
       dose-dependent effect of irradiation on all the biomechanical parameters
       studied. Four of seven parameters were found to be reduced after 2.0
       Mrad of irradiation. Reductions were found in all parameters after 3.0
       and 4.0 Mrad of irradiation.
 DE    Biomechanics  Bone and Bones/*RADIATION EFFECTS  *Bone Transplantation
       Cadaver  Case-Control Studies  Dose-Response Relationship, Drug  *Gamma
       Rays  Human  HIV Infections/PREVENTION & CONTROL/VIROLOGY  Knee
       Injuries/*SURGERY  Patella  Sterilization/*METHODS  Tendons,
       Para-Articular/*RADIATION EFFECTS/*TRANSPLANTATION  Tensile Strength
       Tissue Preservation/METHODS  Transplantation, Homologous  JOURNAL
       ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

