“…It is best to combine visualisation of screws with another diagnostic or therapeutic procedures, e.g., spinal probe or caudal epidural injections (Figs. 4,5,6] Measures to reduce screw loosening Improving screw-bone bonding was the target for many studies [13,16,31,32,34,39,42,45,48,49]. The most successful among these was the use of plasma-sprayed HA screws [13,16,32,34,45,49].…”