Other

CALL FOR A CONSENSUS ON VERTEBRA TESTS

  • G. BİRLİK
  • Feza KORKUSUZ
  • O. AKKUŞ
  • N. AKKAŞ

J Turk Spinal Surg 1994;5(3):84-88

İn recent years, the number of tests performed on vertebrae and the number of related papers have increased in such a manner that a proper assessment of ali the data that have been gathered seems to be difficult. There is now a need for standardization studies. The problems are (i) the criteria to be followed in the material selection, (ii) the choice of the parameters to be studied and (İH) the interpretation of the test results. Experimental studies are mainly performed on calf spines, polyester imitations and fresh cadaver speciments. İt is commonly stated that calf spines exhibit uniformity in stiffness among speciments. There is, however, no definition of uniformity. İn addition, there is no universal consensus on the number of samples and the number of vertebrae to be tested. Accordingly, we need a Standard describing "determination, verification and application of precision data" and "the requirements for laboratories". The temperature and the humidity of the laboratory and the pre-test freezing tem-perature of the spinal speciment should be standardized. Cross-head speeds, number of cycles, maximum ap-plied load values, upper and lovver limits of loads or dispiacement in cyclic loading, preload vaiues, measures tak-en to decelerate biological deterioration during tests, test time, ete. largely differ from laboratory to laboratory. İn order to see the effect of the above mentioned parameters in axial and cyclic loading of vertebrae, we have performed a series of tests in our laboratory. We believe that if a consensus is reached for (i) the criteria for the selection of test materials and (ii) the test conditions, the interpretation of the test results will be more uniform and the conclusions will be more dependable.

Keywords: Spine, Biomechanics, Consensus