Comparison of different strategies on three-dimensional correction of AIS: which plane will suffer?

PURPOSE

There are distinct differences in strategy amongst experienced surgeons from different 'scoliosis schools' around the world. This study aims to test the hypothesis that, due to the 3-D nature of AIS, different strategies can lead to different coronal, axial and sagittal curve correction.

METHODS

Consecutive patients who underwent posterior scoliosis surgery for primary thoracic AIS were compared between three major scoliosis centres (n = 193). Patients were treated according to the local surgical expertise: Two centres perform primarily an axial apical derotation manoeuvre (centre 1: high implant density, convex rod first, centre 2: low implant density, concave rod first), whereas centre 3 performs posteromedial apical translation without active derotation. Pre- and postoperative shape of the main thoracic curve was analyzed using coronal curve angle, apical rotation and sagittal alignment parameters (pelvic incidence and tilt, T1-T12, T4-T12 and T10-L2 regional kyphosis angles, C7 slope and the level of the inflection point). In addition, the proximal junctional angle at follow-up was compared.

RESULTS

Pre-operative coronal curve magnitudes were similar between the 3 cohorts and improved 75%, 70% and 59%, from pre- to postoperative, respectively (P < 0.001). The strategy of centres 1 and 2 leads to significantly more apical derotation. Despite similar postoperative T4-T12 kyphosis, the strategy in centre 1 led to more thoracolumbar lordosis and in centre 2 to a higher inflection point as compared to centre 3. Proximal junctional angle was higher in centres 1 and 2 (P < 0.001) at final follow-up.

CONCLUSION

Curve correction by derotation may lead to thoracolumbar lordosis and therefore higher risk for proximal junctional kyphosis. Focus on sagittal plane by posteromedial translation, however, results in more residual coronal and axial deformity.

Treatment of thoracolumbar kyphosis in patients with mucopolysaccharidosis type I: results of an international consensus procedure

Background

In all patients with mucopolysaccharidosis type I (MPS I), skeletal disease (dysostosis multiplex) is a prominent, debilitating, condition related complication that may impact strongly on activities of daily living. Unfortunately, it is not alleviated by treatment with hematopoietic cell transplantation (HCT) or enzyme replacement therapy (ERT). Although early kyphosis is one of the key features of dysostosis multiplex, there is no international consensus on the optimal management. Therefore, an international consensus procedure was organized with the aim to develop the first clinical practice guideline for the management of thoracolumbar kyphosis in MPS I patients.

Methods

A literature review was conducted to identify all available information about kyphosis and related surgery in MPS I patients. Subsequently, a modified Delphi procedure was used to develop consensus statements. The expert panel included 10 spinal orthopedic surgeons, 6 pediatricians and 3 physiotherapists, all experienced in MPS I. The procedure consisted of 2 written rounds, a face-to-face meeting and a final written round. The first 2 rounds contained case histories, general questions and draft statements. During the face-to-face meeting consensus statements were developed. In the final round, the panel had the opportunity to anonymously express their opinion about the proposed statements.

Results

Eighteen case series and case reports were retrieved from literature reporting on different surgical approaches and timing of thoracolumbar kyphosis surgery in MPS I. During the face-to-face meeting 16 statements were discussed and revised. Consensus was reached on all statements.

Conclusion

This international consensus procedure resulted in the first clinical practice guideline for the management of thoracolumbar kyphosis in MPS I patients, focusing on the goals and timing of surgery, as well as the optimal surgical approach, the utility of bracing and required additional assessments (e.g. radiographs). Most importantly, it was concluded that the decision for surgery depends not only on the kyphotic angle, but also on additional factors such as the progression of the deformity and its flexibility, the presence of symptoms, growth potential and comorbidities. The eventual goal of treatment is the maintenance or improvement of quality of life. Further international collaborative research related to long-term outcome of kyphosis surgery in MPS I is essential as prognostic information is lacking.

Electronic supplementary material

The online version of this article (10.1186/s13023-019-0997-5) contains supplementary material, which is available to authorized users.

Paper #17: Early Onset Scoliosis within the 22q11.2 Deletion Syndrome (22q11.2DS)

22q11.2DS is the most common microdeletion syndrome. It is characterized by a wide phenotypic variability, including scoliosis. This is the first epidemiological study that shows that the prevalence of early onset scoliosis within this vulnerable group of patients is around 40%. A congenital heart defect (CHD) irrespective of surgery was an independent risk factor, with an Odd's Ratio of 12.09.

Plate fixation versus intramedullary fixation for displaced mid-shaft clavicle fractures: a systematic review

Purpose

The optimal surgical approach for displaced midshaft clavicle fracture remains controversial. The objective of this systematic review is to compare functional outcome and complications after plate fixation and intramedullary fixation for displaced midshaft clavicle fractures.

Methods

A computer aided search of PUBMED and Embase was carried out on January 11th 2011. Every study that was published in the English, German, French or Dutch language was considered for inclusion. A total of four studies could be included of which two compared intramedullary fixation versus plate fixation, and two compared intramedullary fixation and plate fixation versus conservative treatment for displaced midshaft clavicle fractures. Studies that compared plate fixation with intramedullary fixation in patients with fresh unilateral displaced midshaft clavicle fractures were included. Dislocation or displacement had to be mentioned in the inclusion criteria of the study for inclusion in this review. The modified version of the Cochrane Bone, Joint and Muscle Trauma Group’s former quality assessment tool was used. Furthermore, the studies included were scored according to the GRADE approach to assess the quality. The chosen studies were summarised in a data-extraction form. Because of the different study designs and characteristics data were summarised separately for each study.

Conclusions

High quality evidence from one study and low quality evidence from three studies showed no difference in functional outcome or complications after plate fixation or intramedullary fixation for displaced midshaft clavicle fractures.

Analysis of the dynamics of bone formation, effect of cell seeding density, and potential of allogeneic cells in cell-based bone tissue engineering in goats

After decades of research, relatively little is known about the role of bone marrow stromal cells (BMSCs) for bone tissue engineering. Although homogeneous cell seeding is regarded optimal, cell survival in large constructs is unlikely, except for the very periphery. Also no minimal and optimal BMSC densities have been identified. An interesting development is the use of allogeneic BMSCs. These have not yet been compared directly to autologous BMSCs. Culture-expanded BMSCs of 10 Dutch milk goats were cryopreserved and peroperatively seeded on 7 mm cubic scaffolds of 65% porous biphasic calcium phosphate (BCP). A range of BMSC densities (per cm3 scaffold) were prepared of 8E2 (= 8 x 10(2)), 8E3, 8E4, 8E5, 8E6 (considered the standard), and 1.6E7. Each goat received a control without cells, the six densities, and an 8E6 allogeneic BMSCs construct intramuscularly. After 3, 5, and 7 weeks, fluorochrome markers were administrated. At 9 weeks, implants were retrieved. The BCP scaffolds appeared to be autoinductive as the controls (without BMSCs) showed some bone. Early bone formation (before 3 weeks) appeared only at the peripheral 2mm of the BMSC-seeded constructs; the later 5- and 9-week labels were found more centrally, suggesting bone migration to the center. There was a minimum of 8E4 and optimum of 8E6 BMSCs/cm3. Allogeneic cells yielded comparable new bone.