Time to augment?! Impact of cement augmentation on pedicle screw fixation strength depending on bone mineral density

• Published in: European spine journal 2018-08, Vol.27 (8), p.1964-1971
• Main Authors: Weiser, Lukas, Huber, Gerd, Sellenschloh, Kay, Viezens, Lennart, Püschel, Klaus, Morlock, Michael M., Lehmann, Wolfgang
• Format: Article
• Language: English
• Subjects: Adult; Aged; Aged, 80 and over; Biomechanical Phenomena - physiology; Bone Cements - therapeutic use; Bone density; Bone Density - physiology; Bone implants; Bone mass; Bone mineral density; Cadaver; Cement; Compression; Computed tomography; Equipment Failure Analysis - methods; Female; Humans; Lumbar Vertebrae - diagnostic imaging; Lumbar Vertebrae - physiopathology; Lumbar Vertebrae - surgery; Male; Materials Testing - methods; Mechanical properties; Medicine; Medicine & Public Health; Middle Aged; Neurosurgery; Original Article; Osteoporosis; Osteoporosis - diagnostic imaging; Osteoporosis - physiopathology; Pedicle Screws; Prosthesis Failure; Spine; Surgical Orthopedics; Tomography, X-Ray Computed; Vertebrae; Young Adult
• ISSN: 0940-6719; 1432-0932
• DOI: 10.1007/s00586-018-5660-7

Purpose Cement augmentation of pedicle screws is known to increase their mechanical strength. Aim was to evaluate the impact of cement augmentation on pedicle screw fatigue strength in dependence of the bone mineral density (BMD). Methods Twenty-one human L2 vertebral bodies from donors between 19 and 96 years of age were used for in vitro experiments. BMD was measured using quantitative computed tomography (QCT). Two pedicle screws were inserted in each specimen and unilaterally augmented with bone cement. Fatigue testing was performed using a cranio-caudal sinusoidal, cyclic load (0.5 Hz) with increasing compression force (100 N + 0.1 N/cycles). Results were evaluated for the BMD groups: normal: BMD > 120 mg/cm 3 , osteopenic: BMD 80–120 mg/cm 3 , and osteoporotic: BMD