Aims

Magnetically controlled growing rods (MCGRs) allow non-invasive correction of the spinal deformity in the treatment of early-onset scoliosis. Conventional growing rod systems (CGRS) need repeated surgical distractions: these are associated with the effect of the ‘law of diminishing returns’.

The primary aim of this study was to quantify this effect in MCGRs over sequential distractions.

Aims. To investigate metallosis in patients with magnetically controlled growing rods (MCGRs) and characterize the metal particle profile of the tissues surrounding the rod. Methods. This was a prospective observational study of patients with early onset scoliosis (EOS) treated with MCGRs and undergoing rod exchange who were consecutively recruited between February 2019 and January 2020. Ten patients were recruited (mean age 12 years (SD 1.3); 2 M:8 F). The configurations of the MCGR were studied to reveal the distraction mechanisms, with crucial rod parts being the distractable piston rod and the magnetically driven rotor inside the barrel of the MCGR. Metal-on-metal contact in the form of ring-like wear marks on the piston was found on the distracted portion of the piston immediately outside the barrel opening (BO) through which the piston rod distracts. Biopsies of paraspinal muscles and control tissue samples were taken over and away from the wear marks, respectively. Spectral analyses of the rod alloy and biopsies were performed to reveal the metal constituents and concentrations. Histological analyses of the biopsies were performed with haematoxylin and eosin staining. Results. Titanium (Ti), vanadium (V), and neodymium (Nd) concentrations in the biopsies taken near the wear marks were found to be significantly higher than those in the control tissue samples. Significantly increased Nd concentrations were also found in the tissues near the barrel of the MCGR. Chronic inflammation was revealed by the histological studies with fibrosis and macrophage infiltration. Black particles were present within the macrophages in the fibrotic tissues. Conclusion. Ti and V were generated mainly at the BO due to metal-on-metal contact, whereas the Nd from the rotor of the MCGR is likely released from the BO during distraction sessions. Phagocytotic immune cells with black particles inside raise concern regarding the long-term implications of metallosis. Cite this article: Bone Joint J 2020;102-B(10):1375–1383

Aims. The aim of this study was to compare the clinical and radiological outcomes of patients with early-onset scoliosis (EOS), who had undergone spinal fusion after distraction-based spinal growth modulation using either traditional growing rods (TGRs) or magnetically controlled growing rods (MCGRs). Methods. We undertook a retrospective review of skeletally mature patients who had undergone fusion for an EOS, which had been previously treated using either TGRs or MCGRs. Measured outcomes included sequential coronal T1 to S1 height and major curve (Cobb) angle on plain radiographs and any complications requiring unplanned surgery before final fusion. Results. We reviewed 43 patients (63% female) with a mean age of 6.4 years (SD 2.6) at the index procedure, and 12.2 years (SD 2.2) at final fusion. Their mean follow-up was 8.1 years (SD 3.4). A total of 16 patients were treated with MCGRs and 27 with TGRs. The mean number of distractions was 7.5 in the MCGR group and ten in the TGR group (p = 0.471). The mean interval between distractions was 3.4 months in the MCGR group and 8.6 months in the TGR group (p < 0.001). The mean Cobb angle had improved by 25.1° in the MCGR group and 23.2° in TGR group (p = 0.664) at final follow-up. The mean coronal T1 to S1 height had increased by 16% in the MCGR group and 32.9% in TGR group (p = 0.001), although the mean T1 to S1 height achieved at final follow-up was similar in both. Unplanned operations were needed in 43.8% of the MCGR group and 51.2% of TGR group (p = 0.422). Conclusion. In this retrospective, single-centre review, there were no significant differences in major curve correction or gain in spinal height at fusion. Although the number of planned procedures were fewer in patients with MCGRs, the rates of implant-related complications needing unplanned revision surgery were similar in the two groups. Cite this article: Bone Joint J 2022;104-B(2):257–264

Aims. We present a case series of five patients who had revision surgery following magnetic controlled growing rods (MGCR) for early onset scoliosis. Metallosis was found during revision in four out of five patients and we postulated a mechanism for rod failure based on retrieval analysis. Patients and Methods. Retrieval analysis was performed on the seven explanted rods. The mean duration of MCGR from implantation to revision was 35 months (17 to 46). The mean age at revision was 12 years (7 to 15; four boys, one girl). Results. A total of six out of seven rods had tissue metallosis and pseudo-capsule surrounding the actuator. A total of four out of seven rods were pistoning. There were two rods which were broken. All rods had abrasive circumferential markings. A significant amount of metal debris was found when the actuators were carefully cut open. Analytical electron microscopy demonstrated metal fragments of predominantly titanium with a mean particle size of 3.36 microns (1.31 to 6.61). Conclusion. This study highlights concerns with tissue metallosis in MCGR. We recommend careful follow-up of patients who have received this implant. Cite this article: Bone Joint J 2016;98-B:1662–7

Aims. The primary aim of this study was to evaluate the performance and safety of magnetically controlled growth rods in the treatment of early onset scoliosis. Secondary aims were to evaluate the clinical outcome, the rate of further surgery, the rate of complications, and the durability of correction. Patients and Methods. We undertook an observational prospective cohort study of children with early onset scoliosis, who were recruited over a one-year period and followed up for a minimum of two years. Magnetically controlled rods were introduced in a standardized manner with distractions performed three-monthly thereafter. Adverse events which were both related and unrelated to the device were recorded. Ten children, for whom relevant key data points (such as demographic information, growth parameters, Cobb angles, and functional outcomes) were available, were recruited and followed up over the period of the study. There were five boys and five girls. Their mean age was 6.2 years (2.5 to 10). Results. The mean coronal Cobb angle improved from 57.6° (40° to 81°) preoperatively, 32.8° (28° to 46°) postoperatively, and 41° (19° to 57°) at two years. Five children had an adverse event, with four requiring return to theatre, but none were related to the device. There were no neurological complications or infections. No devices failed. One child developed a proximal junctional kyphosis. The mean gain in spinal column height from T1 to S1 was 45.4 mm (24 to 81) over the period of the study. Conclusion. Magnetically controlled growth rods provide an alternative solution to traditional growing rods in the surgical management of children with early onset scoliosis, supporting growth of the spine while controlling curve progression. Their use has clear psychosocial and economic benefits, with the reduction of the need for repeat surgery as required with traditional growing rods. Cite this article: Bone Joint J 2018;100-B:507–15

Background:. We have recently shown, using transcranial magnetic stimulation (TMS) to assess voluntary activation (VA), that neural drive to back muscles is reduced in subjects with chronic low back pain. There is also evidence that central nervous system drive to abdominal muscles is altered in these subjects, however VA has not yet been assessed for these muscles in healthy subjects; this is the purpose of the present study. Methods:. Twenty one healthy subjects (10M:11F) participated. Electromyographic activity was recorded from back and abdominal muscles and flexor torque was measured using a dynamometer. Subjects performed a series of isometric voluntary contractions (10%–100% MVC) of rectus abdominis during which TMS was applied to the motor cortex. The resulting superimposed twitches (SIT) were measured and VA was derived. Results:. There was a linear relationship between voluntary torque (50–100% MVC) and SIT amplitude and between voluntary torque (50–100% MVC) and VA. VA at a target torque of 100% MVC was less than maximal (∼86%). Time-to-peak amplitude of SITs displayed a linear relationship with voluntary torque between 10%–100% MVC. Discussion:. This study has shown that it is possible to assess VA of abdominal muscles using TMS. Further, it appears that VA is submaximal during maximum voluntary contractions, similar to that observed in back muscles. This may reflect the function of trunk muscles in general, which are routinely used for maintenance of posture. Whether imbalances of abdominal and back muscle strength observed in low back pain are reflected in imbalances of neural drive to these muscles remains to be investigated

Aim:. To determine the efficacy and safety of the Magec system in early onset scoliosis (EOS). Methods:. In 2011, 6 males and 2 females had Magec rods, with an average age of 8.5 years (2.9–12.7 years), 7 patients had dual rods, and 1 had single. The main cause of EOS was idiopathic scoliosis (n=6), followed by Congenital (n=1), and Syndromic (n=1). Average follow up was 19.4 months (14–26 months). 4 of these patients had their previous Paediatric Isola growing rods exchanged to Magec, and 1 patient had an exchange from single to Dual Magec rods. Results:. In total, the cohort of patients underwent 65 extensions in clinic with an average 8 each (4–19). The first rod extension was performed at an average of 4.6 months following surgery. From there on extensions were done at two monthly intervals on an average. A total of 75 radiographs were taken after Magec insertion, ranging from 5 to 15 per patient. The mean pre-operative Cobb angle 59° improved to 41° at final follow up. This is a mean reduction of 31%. The mean pre-operative T1-S1 length was 305mm which improved to 349mm at final follow up. A mean increase in spinal length of 14%.m. During follow up, 5 complications were noted: 2 metalwork pullouts, 1 extension failure, 1 rod fracture and 1 patient had dermatitis at site of wound. Conclusion:. Our early results using the Magec magnetic growing rod system are encouraging with maintenance of curve correction and in achieving trunk growth in EOS. Conflict Of Interest Statement: No conflict of interest

Purpose. The aim of this study is to assess the safety and efficacy of a remote-operated magnetic growth rod in the treatment of 11 patients with progressive early onset scoliosis (EOS). Introduction. The Growth rod technique (GR) has been a viable treatment option for progressive early onset scoliosis (EOS). However, an increased complication rate has been associated with conventional GR due to frequent surgeries required for lengthening. The safety and efficacy of a remote-operated magnetic growth rod (RO-MGR) has been previously reported in a porcine model. We are reporting the preliminary clinical results of this device which obviates the need for repeated surgeries. Methods. Prospective analysis of early clinical and radiographic data of 11 patients, with EOS, undergoing index RO-MGR treatment and at least 3 distractions. The mean age was 8 years (Range 5-12 years). Four patients had single rod (SR) instrumentation and the remaining 7 had a dual rod (DR) construct. Diagnosis was idiopathic 3, neuromuscular 3, congenital 3, syndromic 1 and neurofibromatosis one. In total, 57 rod distractions were performed. Distractions were performed in the clinic without anesthesia or analgesics. The mean preoperative Cobb angle was 68° (range 46°-108°). The mean preoperative T1-S1 length was 304mm (range 243-361mm). Results. Average distraction was 3.2 per patient. The mean lag before the first distraction was 66 days (28-112) and between distractions was 43 days (42-98). Superficial infection occurred in 1 (SR), prominent rod in 1 (DR), hook pull-out in 1(DR), iatrogenic shortening 1(DR) and loss of length in 2 patients (6/57 rod distraction, 11%, all SR), this loss was regained in subsequent distractions. Apart from a case of proximal rod trimming, no further surgery was required in our group of patients. Mean follow-up was 8 months (6-13). Conclusion. Preliminary results indicate that RO-GR appears to be safe and provided a comparable distraction to the standard GR procedure without the need for repeated open surgeries. No major complications were observed in the short follow up period

Generally, it is considered to be safe in preventing iatrogenic instability if half of the facet joint is left intact during decompression surgeries. By removing half of the facets can we get adequate decompression of the nerve roots? Is there a difference at different levels in the lower lumbar spine? What is the inclination of the facet joint at each level and how does it affect the stability?. Retrospective study. We analysed 200 consecutive magnetic reasonance imaging (MRI) scans of the lumbosacral spine at L3/4, L4/5, and L5/S1 levels. We measured the difference in the distance from midline to the lateral border of the foramen and from midline to the middle of the facet joint at each level on either sides. The angle of the facet joint was also noted. The distance to the foramen from the level of the middle of the facet joints seem to be between 5-6mm lateral at every level. The angle of the facet joints at L3/4 is 35.9°+/−7.4°, while at L4/5 it is 43.2°+/−8.0°, and at L5/S1 it is 49.4°+/−10.1°. In lumbar spine decompression surgeries, after the midline decompression extending up to half of the facet joints, a further undercutting of the facet joints to 5-6mm is therefore required to completely decompress the nerve root in the foramen. The more coronal orientation of the facet joint at L5/S1 conforms better stability than that at L3/4level. Therefore, stabilisation of the spine should be considered if more than 2cm of the posterior elements are removed from midline at L3/4 level

Aim:. The Magnetic Expansion Control Rod Device (Magec) allows controlled distraction of the immature spine for the treatment of early onset scoliosis. There disparity between the reported distraction on the external adjustment device (EAD) and true distraction achieved has not been commented on to date. This study aims to determine the disparity between ‘true’ (T) and ‘apparent’ (A) distraction. Our secondary aim was to assess truncal growth and development. Methods:. Thirteen patients underwent an average of 4.4 (3–6) three monthly distractions. The amount of true distraction was determined by measuring the expansion gap on radiographs using the width of the rod as a conversion factor to allow for magnification. The total distraction to date was compared to the amount reported on the EAD. Sitting and standing heights were recorded at each distraction. Results:. The average number of distractions was 4.4 (range 3–6). The average ‘true’ distraction was 9.1mm compared to 17.2mm ‘apparent’ distraction representing a TA ratio of 1:1.9. The average difference between the total distraction to date measured on the ERC and that measured radiographically was 8.3mm. Sitting and standing heights increased in all patients by an average of 4.3 cm and 7.8 cm per year. Discussion:. The TA ratio of 1:1.9 suggests that for every unit of distraction registered on the EAD approximately 50% of true distraction occurs in vivo. Despite the difference in true versus apparent distraction, an increase in sitting and standing heights was observed in all patients sufficient to maintain growth and development. Conflict Of Interest Statement: No conflict of interest

Conventional growing rods are the most commonly used distraction-based devices in the treatment of progressive early-onset scoliosis. This technique requires repeated lengthenings with the patient anaesthetised in the operating theatre. We describe the outcomes and complications of using a non-invasive magnetically controlled growing rod (MCGR) in children with early-onset scoliosis. Lengthening is performed on an outpatient basis using an external remote control with the patient awake.

Between November 2009 and March 2011, 34 children with a mean age of eight years (5 to 12) underwent treatment. The mean length of follow-up was 15 months (12 to 18). In total, 22 children were treated with dual rod constructs and 12 with a single rod. The mean number of distractions per patient was 4.8 (3 to 6). The mean pre-operative Cobb angle was 69° (46° to 108°); this was corrected to a mean 47° (28° to 91°) post-operatively. The mean Cobb angle at final review was 41° (27° to 86°). The mean pre-operative distance from T1 to S1 was 304 mm (243 to 380) and increased to 335 mm (253 to 400) in the immediate post-operative period. At final review the mean distance from T1 to S1 had increased to 348 mm (260 to 420).

Two patients developed a superficial wound infection and a further two patients in the single rod group developed a loss of distraction. In the dual rod group, one patient had pull-out of a hook and one developed prominent metalwork. Two patients had a rod breakage; one patient in the single rod group and one patient in the dual rod group. Our early results show that the MCGR is safe and effective in the treatment of progressive early-onset scoliosis with the avoidance of repeated surgical lengthenings.

Cite this article: Bone Joint J 2013;95-B:75–80.

Aims

Magnetically controlled growing rod (MCGR) systems use non-invasive spinal lengthening for the surgical treatment of early-onset scoliosis (EOS). The primary aim of this study was to evaluate the performance of these devices in the prevention of progression of the deformity. A secondary aim was to record the rate of complications.

Purpose of the study

The aim of this work was to study the influence of the slice orientation of T2 axial images in numerical measurements of DSCA and study the effect that this change of slice angle would have on the morphological grading assessment.

MRI scanning of spinal patients at the Primary Care Triage stage is pivotal in reducing inappropriate referrals into Secondary Care.

A retrospective study was undertaken. Details of patients from spinal triage clinics referred for MRI scan were collated together with a provisional diagnosis. Following imaging the results and management plan were documented.

2191 Patients referred via GP's to Physiotherapy Specialist- lead spinal triage clinics from April to September 2009 inclusive.

Referred to a spinal consultant routine/urgent, Managed conservatively, Failed to attend for MRI scanning or MRI cancelled, Sent for scanning for reassurance and discharged.

Of 2191 patients seen in a 6-month period 194 (9%) were referred for MRI of which 81 (41%) were referred on to spinal consultant. This equates to 3.7% of the total number of patients triaged.

Specialist physiotherapy diagnosticians with access to MRI scanning, allows simultaneous treatment and seamless transfer to spinal consultants for surgical intervention if appropriate¹. This process is used effectively to manage large numbers of spinal referrals and minimises the number of patients seen unnecessarily in secondary care¹. This is only possible with close multidisciplinary team working².

Aim

The purpose of this study is to compare the pre and post-operative magnetic resonance image clarity of titanium and PEEK based cervical arthroplasty devices at the level of implantation and adjacent level discs.

Abstract. MAGnetic Expansion Control (MAGEC) rods are used in the surgical treatment of children with early onset scoliosis. The magnetically controlled lengthening mechanism enables rod distractions without the need for repeated invasive surgery. The CE certification of these devices was suspended in March 2021 due, primarily, to performance evidence gaps in the documents provided by the manufacturer to regulators and notified bodies. MAGEC rods are therefore not permitted for use in countries requiring CE marking. This was a survey of 18 MAGEC rod surgeons in the UK about their perception of the impact of the CE suspension on the clinical management of their patients. Unsurprisingly, virtually all perceived a negative impact, reflecting the complexity of this patient group. Reassuringly, these surgeons are highly experienced in alternative treatment methods. Cite this article: Bone Jt Open 2022;3(2):155–157

Background. FORECAST is a prospective longitudinal cohort study exploring mechanism-based prognostic factors for pain persistence in sciatica. Here, we share an update on this largest deeply-phenotyped primary care sciatica cohort. Methods/results. Our cohort includes 180 people with sciatica (score >4 on Stynes’ Sum Score), aged 18–85, within 3 months of symptom onset. Psychosocial factors, self-reported sensory profiling, clinical examination, quantitative sensory testing (QST), biological samples (blood and skin samples), and Magnetic Resonance Neurography of lumbar nerve roots were collected at baseline. Pain persistence was determined at three and twelve months with the Sciatica Bothersomeness Index (SBI) and a numeric pain rating scale (NRS) as primary outcomes. Recruitment nears completion, with 160 participants enrolled to date. 127 and 96 participants have completed 3 and 12 months follow-up respectively. Overall, 56% of our cohort are female, with a mean age (SD) of 54.14yrs (16.57). Ethnicity data approximates local populations. SBI at baseline was (median [IQR]) 13[10-17], and interim longitudinal data shows stepwise improvement at 3 and 12 months. Baseline ‘average’ pain intensity was 5.56 (2.15) for leg pain, and 4.14(2.82) for low back pain (LBP). Overall, pain scores decreased at 3 and 12 months, with greater reductions in leg pain than LBP at 12 months. However, around 55–80% and 40–65% of people reported persistent pain at 3 and 12 months respectively. Conclusion. Leg pain severity was moderate and higher than LBP at baseline. All primary outcome measures demonstrate improvement over time, however 40–65% of patients report persistent pain at 12 months. Conflicts of interest. LR: Paid facilitation of post-graduate courses internationally. SK, MT, FP, KM, WS, CP, CR, SC: No conflicts of interest. GC: Editor in Chief of Health Psychology Review. Director of board of directors, MentalCHealth Care setting NoordWestVlaanderen. JF: Copyright holder of ODI (Oswestry Disability Index). Served on a data monitoring committee for a clinical trial of 2 different surgical approaches to cervical disc herniation (FORVAD). Member of HTA Prioritisation Committee B: Inside hospital Care from 2015-February 2019. Member of HTA Interventional Procedures Panel from 2010–2015. Trustee and board member of 3 spine related charities – Back to Back; British Scoliosis Research Foundation and BackCare. Expert instructed by both claimant and defendant solicitors in negligence and person injury cases. GB: Paid consultancy (RNA-seq) with Ivy Farm and Coding.bio. ABS: Paid post-graduate lecturing internationally. Co-chair NeupSig sciatica working group (unpaid). Sources of funding. This project is funded by UKRI and Versus Arthritis as part of the UKRI Strategic Priorities Fund (SPF) Advanced Pain Discovery Platform (APDP), a co-funded initiative by UKRI (MRC, BBSRC, ESRC), Versus Arthritis, the Medical Research Foundation and Eli Lilly and Company Ltd (Grant MR/W027003/1). Additional funding has been received from the back to back charity to expand longitudinal components of the study. LR has received support with PhD fees from the CSP charitable trust. ABS is supported by a Wellcome Trust Clinical Career Development Fellowship. (222101/Z/20/Z). WS is partly funded through the National Institute for Health and Care Research (NIHR) Biomedical Research Centre at the South London and Maudsley NHS Foundation Trust and King's College London. FP is funded by a Dorothy Hodgkin Career Development Fellowship in Chemistry in association with Somerville College. GB is supported by the Wellcome Trust (223149/Z/21/Z) and Diabetes UK (19/0005984). GC and KRM are partly funded by UKRI and Versus Arthritis as part of the Advanced Pain Discovery Platform (APDP) PAINSTORM (MR/W002388/1). The UKRI and Versus Arhthritis (APDP) are the major funders of FORECAST. All other funders provided either some people support, or funded projects with legacy data that we reuse

We recorded compound muscle action potentials (CMAPs) from the diaphragm in 15 normal volunteers, nine patients with lesions of the lower cervical cord (C5 to C8), one completely quadriplegic patient (C6) and seven patients with lesions at a higher cervical level (C1 to C4). Transcranial magnetic stimulation and electrical stimulation of the phrenic nerve were carried out. When the centre of the coil was placed on the interauricular line at a point 3 cm lateral to the vertex on the scalp, the CMAPs from the diaphragm had the largest amplitude and the shortest latency. There was no difference in the mean latency of the CMAPs recorded by transcranial magnetic stimulation in the normal volunteers and in the patients with lesions of the lower cervical cord. In the quadriplegic patient, the latency of the CMAPs was not delayed, but was prolonged in the patients with lesions at a higher level. Those evoked by electrical stimulation of the phrenic nerve were not prolonged in the patients with higher lesions. Our findings suggest that the prolongation of the latency by transcranial magnetic stimulation reflects dysfunction of the higher cervical cord. The combination of transcranial magnetic stimulation and electrical stimulation of the phrenic nerve can detect the precise level of the lesion in the motor tract to the diaphragm

Aims

The aim of this study was to compare outcomes after growth-friendly treatment for early-onset scoliosis (EOS) between patients with skeletal dysplasias versus those with other syndromes.

Background. Mesenchymal stem cells (MSCs) are undergoing evaluation as a potential new therapy for immune and inflammatory-mediated conditions such as IVD degeneration (IDD). Both adipose (ASCs) and bone-marrow (BMSCs) derived MSCs have been widely used in this regard. The optimal tissue source and expansion conditions required to exploit the regenerative capacity of these cells are not yet fully elucidated. In addition the phenotypic response of transplanted cells to the disease environment is not well understood. In this study, ASCs and BMSCs were exposed to a combination of hypoxic conditioning and selected inflammatory mediators, conditions that mimic the microenvironment of the degenerate IVD, in an effort to understand their therapeutic potency for in vivo administration. Methods and Results. Donor-matched ASCs and MSCs were pre-conditioned with either IL-1β (10ng/ml) or TNFα (10ng/ml) for 48 hours under hypoxic conditions (5% O. 2. ). Conditioned media was collected and 45 different immunomodulatory proteins were analysed using human magnetic Luminex® assay. Secreted levels of several key cytokines and chemokines, both pro- and anti-inflammatory, were significantly upregulated in ASCs and BMSCs following the conditioning regime. Under all conditions tested, ASCs expressed significantly higher levels of IL-4, IL-6, IL-10, IL-12, TGF-α, and GCSF compared to BMSCs. Pre-conditioning with TNFα resulted in significantly higher levels of IL-10 while preconditioning with IL-1β resulted in higher levels of IL-6, IL-12 and GCSF. Conclusion. These data suggest that pre-conditioned ASCs may have enhanced therapeutic potential in modulating IVD repair through the increased release of trophic factors that play a role in immunomodulation. Conflicts of interest: None. Sources of funding: Financial support for this research was provided by EU Horizon 2020 RESPINE grant (Project ID# 732163)