Martin Gehrchen1, Sajan K Hegde2, Mark Moldavsky3, Suresh Chinthukunta4, Manasa Gudipally4, Brandon Bucklen4, Kanaan Salloum4, Saif Khalil4. 1. Spine Unit, Department of Orthopaedic Surgery, Rigshospitalet, National University Hospital of Copenhagen, Skolevej 14, Gentofte, 2820, Copenhagen, Denmark. 2. Apollo Hospital, 21 Greams Lane, Chennai, India. 3. Musculoskeletal Education and Research Center (MERC), A Division of Globus Medical Inc., 2560 General Armistead Ave, Audubon, PA, 19403, USA. mmoldavsky@globusmedical.com. 4. Musculoskeletal Education and Research Center (MERC), A Division of Globus Medical Inc., 2560 General Armistead Ave, Audubon, PA, 19403, USA.
Abstract
STUDY DESIGN: An in vitro biomechanical study. OBJECTIVES: To compare the biomechanical stability of traditional and low-profile thorocolumbar anterior instrumentation after a corpectomy with cross-connectors. Dual-rod anterior thoracolumbar lateral plates (ATLP) have been used clinically to stabilize the thorocolumbar spine. METHODS: The stability of a low-profile dual-rod system (LP DRS) and a traditional dual-rod system (DRS) was compared using a calf spine model. Two groups of seven specimens were tested intact and then in the following order: (1) ATLP with two cross-connectors and spacer; (2) ATLP with one cross-connector and spacer; (3) ATLP with spacer. Data were normalized to intact (100 %) and statistical analysis was used to determine between-group significances. RESULTS: Both constructs reduced motion compared to intact in flexion-extension and lateral bending. Axial rotation motion became unstable after the corpectomy and motion was greater than intact, even with two cross-connectors with both systems. Relative to their respective intact groups, LP DRS significantly reduced motion compared to analogous DRS in flexion-extension. The addition of cross-connectors reduced motion in all loading modes. CONCLUSIONS: The LP DRS provides 7.5 mm of reduced height with similar biomechanical performance. The reduced height may be beneficiary by reduced irritation and impingement on adjacent structures.
STUDY DESIGN: An in vitro biomechanical study. OBJECTIVES: To compare the biomechanical stability of traditional and low-profile thorocolumbar anterior instrumentation after a corpectomy with cross-connectors. Dual-rod anterior thoracolumbar lateral plates (ATLP) have been used clinically to stabilize the thorocolumbar spine. METHODS: The stability of a low-profile dual-rod system (LP DRS) and a traditional dual-rod system (DRS) was compared using a calf spine model. Two groups of seven specimens were tested intact and then in the following order: (1) ATLP with two cross-connectors and spacer; (2) ATLP with one cross-connector and spacer; (3) ATLP with spacer. Data were normalized to intact (100 %) and statistical analysis was used to determine between-group significances. RESULTS: Both constructs reduced motion compared to intact in flexion-extension and lateral bending. Axial rotation motion became unstable after the corpectomy and motion was greater than intact, even with two cross-connectors with both systems. Relative to their respective intact groups, LP DRS significantly reduced motion compared to analogous DRS in flexion-extension. The addition of cross-connectors reduced motion in all loading modes. CONCLUSIONS: The LP DRS provides 7.5 mm of reduced height with similar biomechanical performance. The reduced height may be beneficiary by reduced irritation and impingement on adjacent structures.
Authors: Darrel S Brodke; Sohrab Gollogly; Kent N Bachus; R Alexander Mohr; Bao-Khang N Nguyen Journal: Spine (Phila Pa 1976) Date: 2003-08-15 Impact factor: 3.468
Authors: Dean Chou; Adolfo Espinoza Larios; Robert H Chamberlain; Mary S Fifield; Roger Hartl; Curtis A Dickman; Volker K H Sonntag; Neil R Crawford Journal: J Neurosurg Spine Date: 2006-03