Bone Growth after Spine Fusion

Kyphectomy in Children with Myelomeningocele

“…In addition to our patients with pseudarthrosis and implant failure, we had four additional patients with implant failure that did not require any further intervention and remained stable with no loss of correction. It is possible these patients had undetected radiographic subtle pseudarthrosis [13], but none of these patients were further worked up with other imaging studies to verify this. We do not believe asymptomatic patients with no loss of correction require revision.…”

Volumetric determination of normal and scoliotic vertebral bodies

“…Methods used for evaluation of vertebral growth [18] or vertebral remodelling after spine surgery are based on measurements of distances between selected points on radiographs of the concerned vertebrae [11,12,14,17] or the disc [15,16] for indirect estimation of the vertebral growth.…”

“…There are several reports on vertebral growth per se [4,18] and in relation to clinical aspects of idiopathic scoliosis (IS) [19,22], in Scheuermann's disease [6,20] and in relation to the pathomechanism in experimental scoliosis [15]. There are also reports on vertebral growth asymmetry during developement of scoliosis [3,18] and still others vertebral growth after posterior spinal fusion [11,14,17] or after spinal inAbstract A new method is presented for stereological evaluation of the volume of the vertebral body in vivo. The height of the vertebral body is measured at three standardised points on an anteroposterior radiograph and at two other points on a lateral one.…”

Pedicle shifting or migration as one of the causes of curve progression after posterior fusion: an interesting case report and review of literature

“…Authors have constantly reported failures of scoliosis correction with correction being lost over a variable period of followup depending on the velocity of spine growth and growth spurts left. Various reasons have been ascribed to this loss of correction over time including 'crankshaft effect' [12][13][14][15][16][17][18], continued vertical growth of the anterior part of the spine after posterior fusion, 'biological plasticity' [19][20][21][22][23][24][25][26][27][28], pseudoarthrosis, implant failure/breakage, selection of wrong levels of fusion/stopping too short [29], compensatory changes in nonfused segments of spine, excessive apical translation during rod de-rotation maneuvers [30], etc. Few authors have stressed that crankshaft effect is difficult after segmental pedicle screw-rod instrumentation because it gives a rigid, tricolumn stability in all planes against the forces of the growing spine [5][6][7][8][9][10] but an increasing number of authors have reported progressive scoliosis in the growing spine after segmental pedicle screw-rod constructs also indicating that crankshaft phenomenon probably does occur after segmental instrumentation [17,18,25,27,31,32].…”

“…Few authors have stressed that crankshaft effect is difficult after segmental pedicle screw-rod instrumentation because it gives a rigid, tricolumn stability in all planes against the forces of the growing spine [5][6][7][8][9][10] but an increasing number of authors have reported progressive scoliosis in the growing spine after segmental pedicle screw-rod constructs also indicating that crankshaft phenomenon probably does occur after segmental instrumentation [17,18,25,27,31,32]. The shifting or migration of pedicles observed in this case probably occurred owing to longitudinal growth of immature, plastic fusion mass [19][20][21][22][23][24][25][26][27][28]. If this indeed occurs, it can explain at least a few cases of progressive loss of correction after segmental instrumentation.…”