Systematic review of the complications associated with magnetically controlled growing rods for the treatment of early onset scoliosis.

PURPOSE: To analyse the complication profile of magnetically controlled growing rods (MCGRs) in early onset scoliosis (EOS). METHODS: This is a systematic review using PUBMED, Medline, Embase, Google Scholar and the Cochrane Library (keywords: MAGEC, Magnetically controlled growing rods and EOS) of all studies written in English with a minimum of five patients and a 1-year follow-up. We evaluated coronal correction, growth progression (T1-S1, T1-T12) and complications. RESULTS: Fifteen studies (336 patients) were included (42.5% male, mean age 7.9 years, average follow-up 29.7 months). Coronal improvement was achieved in all studies (pre-operative 64.8°, latest follow-up 34.9° p = 0.000), as was growth progression (p = 0.001). Mean complication rate was 44.5%, excluding the 50.8% medical complication rate. The unplanned revision rate was 33%. The most common complications were anchor pull-out (11.8%), implant failure (11.7%) and rod breakage (10.6%). There was no significant difference between primary (39.8%) and conversion (33.3%) procedures (p = 0.462). There was a non-statistically significant increased complication rate with single rods (40 vs. 27% p = 0.588). CONCLUSIONS: MCGRs improve coronal deformity and maintain spinal growth, but carry a 44.5% complication and 33% unplanned revision rate. Conversion procedures do not increase this risk. Single rods should be avoided. These slides can be retrieved under Electronic Supplementary material.

Targeted Distraction: Spinal Growth in Children With Early-Onset Scoliosis Treated With a Tail-gating Technique for Magnetically Controlled Growing Rods.

STUDY DESIGN: Prospective cohort study OBJECTIVE.: To understand the efficacy of a tail-gating technique (TGT) to mirror the normal spinal growth of children with early-onset scoliosis (EOS) treated with magnetically controlled growing rods (MCGR). SUMMARY OF BACKGROUND DATA: MCGR allow outpatient distraction and guided spinal growth without the need for repeat surgery. Two techniques (maximal and targeted) are currently employed to determine the distraction amount, however the efficacy of each is unknown. This study specifically assesses the ability of targeted distraction to achieve physiological growth. METHODS: We performed a retrospective review of European children treated with MCGR using a TGT and analyzed the post-operative clinical and radiographic outcomes, including the sitting height, standing height, coronal Cobb angle, T1-T12 and T1-S1 height. Furthermore, we compared the post-operative sitting/standing height ratio every 6 months to those reported for normal age- and sex-matched European children. RESULTS: Thirty-five children were included with a mean follow-up of 3.4 years (1.8-5.8 years). All clinical and radiographic parameters significantly (P < 0.05) improved immediately post-operatively and were maintained until final follow-up. The TGT mirrored the normative sitting/standing height ratios for expected spinal growth (Pearson correlation 0.95 for males and 0.90 for females). The mean difference between the reference values for the sitting/standing height ratio and our results was 0.0124 (P < 0.001) for males and 0.0068 (P = 0.010) for females. CONCLUSION: MCGR can reliably improve the coronal deformity in children with EOS while maintaining spinal growth. A TGT to determine the distraction amount at follow-up accurately mirrors the normal growth pattern of age-, sex-, and ethnicity-matched children. However, patients treated with this technique have a statistically significant, but clinically insignificant, shorter than physiologically normal spinal height. LEVEL OF EVIDENCE: 3.

Adverse local tissue reaction after 2 revision hip replacements for ceramic liner fracture: A case report.

INTRODUCTION: In younger patients, ceramic-on-ceramic (CoC) bearing surfaces are usually recommended for total hip replacement (THR) because of their low wear rate and longer expected functional life. Although technical advancements have reduced the risk of ceramic bearings fracture, this complication remains a major concern. CASE DESCRIPTION: We present the case of a 56-year-old patient undergoing 3 revision hip arthroplasties of the right hip due to ceramic liner fractures. Initial THR (2008) was performed with a CoC bearing, followed by liner fracture due to trauma a year later. The acetabular component and liner were replaced, with a minor incongruence between the old head and new insert. The 2nd ceramic insert fractured 3.5 years later, following minor trauma. Upon revision, the bearing surface was changed to metal-on-polyethylene (MoP). The performed retrieval analysis demonstrated stripe and rim wear, and evidence of adhesive wear. The patient was referred to us a month later, with a fistula on the lateral side of the hip, discharging black, petroleum-like liquid. Radiology showed well-fixed implants, no dislocation and no apparent polyethylene wear. Microbiological assessment of the discharge showed no infection. Intraoperatively massive metallosis was noticed, with stable acetabular and femoral components. The metal femoral head was heavily abraded, with almost 1% volumetric wear. Hematoxylin and eosin stained frozen tissue samples showed muscular and adipose tissue necrosis, while polarized light microscopy highlighted metal, polyethylene, and ceramic particles. CONCLUSION: The present case is yet another report showing the adverse outcomes of using MoP bearings for revision after ceramic liner fracture in THR.

Sagittal balance parameters correlate with spinal conformational type and MRI changes in lumbar degenerative disc disease: results of a retrospective study.

PURPOSE: Spinopelvic parameters can be useful in identifying risk factors for lumbar degenerative disc disease, but few studies assess patients with single-level disc herniation and most do not evaluate symptoms. This comparative retrospective study was aimed to analyse spinopelvic parameters, symptoms and MRI changes in patients with single-level lumbar disc herniation undergoing conservative or surgical treatment. METHODS: Patients with clinical and radiological assessment (Japanese Orthopaedic Association Score) and an MRI evaluation of the lumbar spine were identified and divided into two groups: surgically treated (group A) and not requiring surgery (group B). Spinopelvic parameters were determined on standing profile radiographs of the lumbar spine and pelvis, and mean values were compared to those reported in the literature for normal subjects. MRI findings were graded according to the system described by Pfirrmann et al. RESULTS: The study included 71 patients with single-level lumbar disc herniation: 26 in group A (39.4 ± 12.1 years) and 45 in group B (51.4 ± 17.2 years). The notable differences in spinopelvic parameter means between the two groups did not reach statistical significance. A positive correlations of age with pelvic tilt and Pfirrmann changes with pelvic incidence was only found in group A, while both groups showed highly significant positive correlations of pelvic incidence with the spine's conformational type (p = 0.001). CONCLUSIONS: Characteristic changes in spinopelvic parameters identified in patients with lumbar degenerative disc disease were a reduction in pelvic incidence, sacral slope and lumbar lordosis, with an increased pelvic tilt. These were found to correlate with MRI changes in surgically treated patients.

Utility of the pedicle subtraction osteotomy for the correction of sagittal spine imbalance.

INTRODUCTION: Pedicle substraction osteotomy (PSO) in the lumbar spine is indicated in the treatment of large sagittal deformities of the lumbar spine. Substantial complications associated with PSOs include pseudarthrosis and mechanical failure. The purpose of the present study was to assess the complications of this procedure and the causes of mechanical complications. MATERIAL AND METHODS: Fifteen patients aged between 38 and 79 years (mean age 63.8±12.82) were operated on between June 2011 and September 2014 for sagittal imbalance by means of one-level PSO. Pre-operative and post-operative values of radiological spino-pelvic sagittal parameters were measured. Clinical and radiological evaluations were conducted pre-operatively and post-operatively at six months and one year. Clinical evaluation included intra- and post-operative complications. RESULTS: Mean pelvic incidence was 54.86 ± 11.82°. Lumbar lordosis (LL) was measured to be 12.26 ± 18.48° pre-operatively and increased to 42.73 ± 14.05° post-operatively (p< 0.05). Mean gain of lordosis after PSO at index level was calculated to be 28 ± 11° (range, 14-41). SVA decreased post-operatively from 93.46 ± 36.69 mm to 61.73 ±38.68 mm (p< 0.05). Several complications (n = 8), including two minor (one dural tear with no clinical consequences and one transient radicular deficit) and six major with re-intervention, were observed in our series. DISCUSSIONS: Optimal post-operative correction in the sagittal plane: SVA <50 mm, LL= -(PI+10°) is an important parameter to reduce the risk of developing sagittal decompensation which is a common condition after PSO. Rate of complications after PSO is not negligible in the literature up to 45%. CONCLUSIONS: The main cause of mechanical complications was insufficient sagittal correction. To limit the risk of mechanical complications and to achieve a good sagittal balance, PSO must be associated with additional SPOs or a second corrective surgery to obtain a solid anterior fusion.