Case series of four complex spinal deformities: new frontiers in pre-operative planning

BACKGROUND AND AIM

Osseous and medullar anomalies constitute a hard challenge for interpretation of complex vertebral deformities anatomy. To better frame these deformities three-Dimensional (3D) printing represents a new frontier in this field. The aim of this brief report is describing the use of 3D printed models for surgical planning in four complex vertebral deformity cases treatment.

METHODS

Four cases of severe scoliosis were treated between December 2017 and January 2019; patients' mean age was 12,25 years. Two patients underwent neurosurgical intervention for myelomeningocele at the time of birth. Standard and dynamics X-Ray, Computed Tomography (CT) and Magnetic Resonance (MR) of the column were performed pre-operatively. CT files were implemented to build the 3D model of each spine and selected ribs. The models were 3D printed in thermoplastic material, then used to study the deformities and for surgical planning. A survey proposal about 3D models' utility and accuracy has been made to 15 residents and 6 main surgeons.

RESULTS

Preparation of each 3D models required about 316.5 minutes and printing time was about 108 hours each. The average cost was 183.16 € to produce one 3D printed model, which resulted useful in surgical planning and educational.

CONCLUSIONS

The manufacture of 3D models requires time, resources and multidisciplinary approach, it must be justified by complexity of the case. In this study 3D Printing allowed surgeons to carefully plan and simulate the surgery, ensuring for a better sizing of the implant.

Pediatric trans-olecranon fracture dislocation of the elbow associated with fracture of the radial head and with medial collateral ligament lesion: A case report and review of the literature

Introduction

We report what is, to the best of our knowledge, the first case of pediatric trans-olecranon fracture dislocation of the elbow associated with a radial head fracture and with a medial collateral ligament disruption.

Case presentation

A 7-year-old girl presented to the emergency department after a fell on his right elbow while playful activity at home. The elbow X-ray showed acute trans-olecranon fracture dislocation of the elbow associated with a radial head fracture. A pre-operative 3D TC scans confirmed and clarified the injury pattern. However, stress radiographs performed in the operating room under anesthesia revealed an associated severe valgus instability caused by medial collateral ligament disruption. The olecranon fracture was fixed with two crossing 1.5 mm K-wires and the angulated radial neck fracture was fixed with a retrograde 1.5 mm K-wire by S.E.R.I. technique.

Conclusion

Although trans-olecranon fracture dislocation of the elbow is well recognized and clearly described in adults, it is uncommon in children. A pre-operative 3D TC scans are recommended to enable a more accurate diagnosis and surgical planning. Medial collateral ligament has a central role in elbow stability and is very important to repair it during surgery.

Sublaminar fixation versus hooks and pedicle screws in scoliosis surgery for Marfan syndrome

Background:

In patients with Marfan syndrome (MFS), surgical correction of spinal deformities with hooks and/or pedicle screws involves a higher rate of complications than in patients with adolescent idiopathic scoliosis. Therefore, sublaminar instrumentation is often a last resort option. This study wants to assess the ability of sublaminar fixation to achieve three-dimensional scoliosis correction and spine stabilization compared with hook and/or pedicle screw systems.

Methods:

Twenty-one MFS patients who underwent posterior spinal fusion at a highly specialized medical center in 1995–2017 were divided into two different groups retrospectively evaluated at a minimum follow-up of 2 years. Group 1 (8 patients) was composed by hooks and screws instrumentation, while Group 2 (13 patients) was composed by hook or pedicle screw system associated to sublaminar wires/bands. Radiological (correction and long-term stability) and general endpoints (mean blood loss, surgery time, and complications) were compared between the groups.

Results:

The degree of correction compared with the preoperative status was satisfactory with both approaches, although the difference between them was not significant. No significant differences were found for general endpoints between groups.

Conclusion:

Our data suggest that scoliosis correction with sublaminar fixation is not inferior to treatment with hooks and/or pedicle screws.

Level of Evidence:

III.

Surgical treatment of spinal deformities in Marfan syndrome: Long-term follow-up results using different instrumentations

Background:

Scoliosis is the most frequent spinal deformity related to Marfan syndrome (MFS). Treatment with a brace is often ineffective, and surgical treatment is very challenging; many instrumentations were used along the years. Our retrospective study has the purpose of identifying the reliability of different devices in three-dimensional correction of the spine deformities in MFS.

Materials and Methods:

We reviewed retrospectively the records of patients surgically treated, in a single institution between 1999 and 2016, for spinal deformities in MFS. X-rays were reviewed for analyzing the magnitude of the curves in preoperative time (T0), the amount of correction in the immediate after surgery period (T1), and it's stability at follow-up (FU) (T2). The clinical outcomes were also evaluated with the Scoliosis Research Society 24.

Results:

A total of 21 patients with a mean age at surgery of 16 years met inclusion and exclusion criteria. Four different construct types were identified: hooks with sublaminar wires (G1), hooks and pedicle screws (G2), pedicle screws (G3), and pedicle screws with sublaminar wires (G4). The mean FU time was 8 years. The average major scoliosis curve had a mean value of 63.48° at T0 and was corrected to 28.81° at T2. Furthermore, minor curve, thoracic lordosis, and lumbar kyphosis (when associated to scoliosis) were also corrected. Student t-test showed significative differences (P < 0.05) for all curves between T0–T1 and T0–T2 while between T1 and T2, no differences were found. We also evaluated separately the results of each instrumentation, and G3 obtained the best performances.

Conclusions:

Our results shows that screws may guarantee a better correction of the deformities.

Level of Evidence:

III

Hybrid constructs pedicle screw with apical sublaminar bands versus pedicle screws only for surgical correction of adolescent idiopathic scoliosis

PURPOSE

To compare the 2-year minimum postoperative results of posterior correction and spinal arthrodesis using translational correction with hybrid (sublaminar bands on concave side and pedicle screw) constructs versus correction with intermediate density pedicle screw-only constructs in the treatment of AIS (Lenke 1).

METHODS

A total of 37 patients with AIS at single institutions who underwent posterior spinal arthrodesis pedicle screw with sublaminar bands at the apex (19 patients) (Group A) or pedicle screw-only (18) constructs (Group B) were selected and matched according to similar age at surgery 13.8 years (Group A) and 14.3 years (Group B), similar arthrodesis area 12.3 (Group A) and 11.5 (Group B), all curves Lenke type 1 with similar pre-op curve 54° (Group A) and 57° (Group B). Patients were evaluated pre-op, immediately post-op, and at min 2-year follow-up according to radiographic curve correction, operating time, intraoperative blood loss, and f.u. loss of correction.

RESULTS

The average curve correction was 65.6% in sublaminar group and 68% in pedicle screw group. At 2-year follow-up, loss of the major curve correction was 2% in sublaminar group compared to 3% in pedicle screw group. Postoperative coronal and sagittal balance was similar in both groups. Operating time averaged 200 min (Group A) and 180 min (Group B). Intraoperative blood loss was significantly different in both groups 700 ± 160 cc in sublaminar group and 630 ± 150 cc in pedicle screw group. There were no neurologic complications in both groups.

CONCLUSION

The two groups offer similar curve correction without neurologic complications in the surgical treatment of AIS (Lenke 1). The use of sublaminar bands on the apex (concave side) can be a valid fixation in the presence of hypoplastic pedicle, can reduce the thoracic hypokyphosis and derotate the vertebra but had more blood loss comparing to pedicle screws alone. These slides can be retrieved under Electronic Supplementary Material.