Experience With Recombinant Human Bone Morphogenetic Protein-2 in Posterior Lumbar Interbody Fusion: A Retrospective Review of 1019 Procedures.

Background: Recombinant human bone morphogenetic protein-2 (rhBMP-2) combined with an activated collagen scaffold (Infuse; Medtronic, MN) has been used to facilitate lumbar intervertebral fusion; however, data regarding its efficacy are inconsistent. We aimed to assess the efficacy of rhBMP-2 when used in posterior lumbar interbody fusion (PLIF) by analyzing the rate of reoperation for nonunion and patient-reported outcome measures in a large retrospective case series. We also aimed to assess the impact of patient and surgical factors on rates of reoperation and determine frequency of complications.

Risk of adjacent segment disease after 'topping-off' multi-level lumbar fusions with posterior dynamic stabilisers: an observational cohort study.

Purpose: To determine whether 'topping-off' lumbar fusions, using posterior dynamic stabilising devices (PDSs) with specific biomechanical parameters, reduces the risk of adjacent segment disease (ASD).

Methods: Survival analysis of two non-randomised cohorts, with or without 'topping-off' (T/O or NoT/O), compared the risk of further surgery for ASD following multi-level posterior lumbar interbody fusion (PLIF). The study sample comprised consecutive patients, aged 55 + years, with degenerative pathology at 2, 3 or 4 levels.

Cervical sagittal balance: a biomechanical perspective can help clinical practice.

Purpose: In this article, we summarize our work on understanding the influence of cervical sagittal malalignment on the mechanics of the cervical spine.

Methods: Biomechanical studies were performed using an ex vivo laboratory model to study the kinematic and kinetic response of human cervical spine specimens in the setting of cervical sagittal imbalance. The model allowed controlled variations of C2-C7 Sagittal Vertical Alignment (C2-C7 SVA) and T1-Slope so that clinically relevant sagittally malaligned profiles could be prescribed, while maintaining horizontal gaze, and their biomechanical consequences studied.

Is Cervical Sagittal Imbalance a Risk Factor for Adjacent Segment Pathomechanics After Multilevel Fusion?

Study Design: A biomechanical study using human spine specimens.

Objective: The aim of this study was to assess whether the presence of cervical sagittal imbalance is an independent risk factor for increasing the mechanical burden on discs adjacent to cervical multilevel fusions.

Summary Of Background Data: The horizontal offset distance between the C2 plumbline and C7 vertebral body (C2-C7 Sagittal Vertical Axis (SVA)) or the angle made with vertical by a line connecting the C2 and C7 vertebral bodies (C2-C7 tilt angle) are used as radiographic measures to assess cervical sagittal balance.

Postural Consequences of Cervical Sagittal Imbalance: A Novel Laboratory Model.

Study Design: A biomechanical study using human spine specimens.

Objective: To study postural compensations in lordosis angles that are necessary to maintain horizontal gaze in the presence of forward head posture and increasing T1 sagittal tilt.

Summary Of Background Data: Forward head posture relative to the shoulders, assessed radiographically using the horizontal offset distance between the C2 and C7 vertebral bodies (C2-C7 [sagittal vertical alignment] SVA), is a measure of global cervical imbalance.

Monitoring image guidance system accuracy during spinal surgery with mini-screw fiducials: technical note.

Study Design: A technical note.

Objective: To describe a technique for measuring accuracy of intraoperative image guidance systems in spine surgery.

Summary Of Background Data: Image guidance may be of use when performing complex procedures on the spine.