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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: METHODS, BACKGROUND, METHODS. Meshes: Adult, Biomechanical Phenomena, Data Interpretation, Statistical, Humans, In Vitro Techniques, Intervertebral Disc, Lumbar Vertebrae, Male, Middle Aged, Radiography, Rotation, Spinal Diseases.
user
Does disc degeneration affect the multidirectional flexibility of the lumbar spine? Context: An in vitro biomechanical investigation using human lumbar cadaveric spine specimens was undertaken to determine any relationship between intervertebral disc degeneration and nonlinear multidirectional spinal flexibility. Previous clinical and biomechanical studies have not established conclusively such a relationship. Forty-seven discs from 12 whole lumbar spine specimens were studied under the application of flexion-extension, axial rotation, and lateral bending pure moments. Three flexibility parameters were defined (neutral zone (NZ), range of motion (ROM), and neutral zone ratio (NZR = NZ/ROM)) and correlated with the macroscopic and radiographic degeneration.
assistant
In flexion-extension, the ROM decreased and NZR increased with degeneration. In axial rotation, NZ and NZR increased with degeneration. In lateral bending, the ROM significantly decreased and the NZR increased with degeneration. In all three loading directions, the NZR increased, indicating greater joint laxity with degeneration. Final Decision: yes