Evaluation of the effectiveness of expandable cages for reconstruction of the anterior column of the spine

Abstract

Purpose: For anterior spine column reconstruction after corpectomy, expandable cages offer solid anterior support and allow correction of deformity, providing excellent primary stability. To provide a larger body of clinical observations concerning the effectiveness of the approach, this retrospective study examines patients treated by corpectomy and reconstruction with an expandable cage for different pathologies. Methods: Across 5 years, 39 patients underwent vertebral reconstruction with expandable cages after single ( n = 34), double ( n = 4), or triple ( n = 1) corpectomy. Pathologies were tumors ( n = 21), fractures, or deformities in traumatic injuries ( n = 14), degenerative pathology ( n = 2), and infection ( n = 2). Levels were cervical ( n = 10), thoracic ( n = 14), and lumbar ( n = 15). All patients were evaluated clinically and radiographically. Results: There were no cases of neurologic deterioration. Nurick grade showed significant improvement at 3 months postoperative versus preoperative ( p < 0.01). Visual analog scale significantly improved preoperatively versus 3 and 12 months postoperatively (both p = 0). Regional angulation was significantly corrected, from preoperative to 3 and 12 months postoperative, at cervical, thoracic, and lumbar levels. We achieved reconstruction of the normal local anatomy with full recovery of the height of the vertebral body. Six patients (15.4%) had complications and two (5.1%) underwent revision surgery. Conclusions: In our experience, expandable cages confer stable anterior support, providing significant improvement of the segmental kyphosis angle and restoration of the original somatic height. Our clinical results are favorable, and the low rate of complications and revision accentuates the expandable cage as a valuable tool to replace the vertebral body in diverse pathologies and different spine levels.

Application of an Expandable Cage for Reconstruction of the Cervical Spine in a Consecutive Series of Eighty-Six Patients

“…Several clinical studies have shown the efficacy of the expandable cage, mostly in the cervical spine [2][3][4][5][6][7]10,[15][16][17][18][19][20][21]. Most common indications were, similar to our study, cervical spinal canal stenosis [7,12], metastases [5,10,17], fractures [2,6] and spondylodiscitis [4,19].…”

“…Indications include spinal canal stenosis with compression of the spinal cord [1], fracture [2,3], spondylodiscitis [4], and metastases [5]. Corpectomy of the cervical spine is performed through the anterior approach with the need of a graft or implant device for reconstruction [6]. ECs can be adjusted to the size of corpectomy [7], and they offer solid anterior support, providing excellent primary stability [6] with less risk of damage to the end plate, less intraoperative manipulation of the device, and potentially greater control over lordosis in comparison to non-expandable cages [8].…”

“…Corpectomy of the cervical spine is performed through the anterior approach with the need of a graft or implant device for reconstruction [6]. ECs can be adjusted to the size of corpectomy [7], and they offer solid anterior support, providing excellent primary stability [6] with less risk of damage to the end plate, less intraoperative manipulation of the device, and potentially greater control over lordosis in comparison to non-expandable cages [8]. They may be particularly advantageous in cases with poor bone quality, such as patients with osteoporosis or metastatic tumors that have been radiated [8].…”

Biomechanics of artificial pedicle fixation in a 3D-printed prosthesis after total en bloc spondylectomy: a finite element analysis

“…Artificial pedicle fixation not only prevented VBR displacement, but also transferred stress and distributed the load between internal fixations [ 10 ]. Simple artificial pedicle connections have been used to improve fixation stability [ 11 , 12 ]. However, because of the limitations of off-the-shelf VBR designs, a firm connection is rarely achieved.…”

Biomechanics of Artificial Pedicle Fixation in a 3d-printed Prosthesis After Total en Bloc Spondylectomy: A Finite Element Analysis

“…Artificial pedicle fixation not only prevented VBR displacement, but also transferred stress and distributed the load between internal fixations [11]. Simple artificial pedicle connections have been used to improve fixation stability [12,13]. However, because of the limitations of off-the-shelf VBR designs, a firm connection is rarely achieved.…”