MAGEC Rods

Early-onset scoliosis is challenging precisely because the child is still growing. Fusing the spine early — permanently locking the vertebrae together — would correct the curve but would also stop the spine, and with it the chest, from growing, which can seriously harm lung development. So-called "growth-friendly" surgery tries to control the curve while allowing the spine and chest to keep growing. For many years this meant traditional growing rods, which had to be lengthened by taking the child back to the operating theatre every few months for a small surgical procedure. Each of those operations carries its own risk of infection, anaesthetic complications, wound problems, and the cumulative psychological burden of repeated surgery on a young child. Magnetically controlled growing rods were designed to solve exactly this problem: the rod contains an internal magnetic actuator, and it can be lengthened in the outpatient clinic using an external magnetic device, without an operation and usually without an anaesthetic. On paper, this is an elegant idea, and it is easy to understand why it was greeted with enthusiasm.

The evidence that magnetically controlled rods can correct and control an early-onset curve, and can achieve spinal lengthening comparable to traditional growing rods while avoiding the repeated planned operations, is reasonably consistent. Systematic reviews and matched comparisons have reported similar curve correction and spinal growth to traditional rods, with the major advantage of far fewer trips to the operating theatre for routine lengthening. Some comparative work has even suggested better correction and fewer unplanned revisions in certain groups. That is the genuinely positive part of the story, and it should not be dismissed. But the same literature is equally clear that this technology carries a substantial burden of complications. A widely cited systematic review of complications reported an average complication rate around 44% and an unplanned revision rate around a third of patients. In other words, avoiding the routine lengthening operations did not, in practice, mean avoiding surgery altogether — a meaningful proportion of children still needed unplanned procedures. The honest summary is that these rods work broadly as intended at controlling the curve, but at the cost of a high rate of device-related problems.

The concern that has attracted the most attention — and the most legitimate scientific scrutiny — is metallosis: the release of tiny particles of metal (chiefly titanium alloy) from the rod's internal moving parts into the surrounding tissue. Independent analysis of rods removed from children has been sobering. One multicentre explant database reported tissue metallosis in around four-fifths of cases examined. Another explant analysis found titanium wear debris associated with essentially every rod studied, and a high rate of failure of the internal O-ring seal that is meant to keep the mechanism sealed. Further studies documented elevated levels of titanium and other metals in the tissues around the implant, together with signs of chronic inflammation. It is important to be measured here: what remains genuinely uncertain is the long-term biological and whole-body significance of this metal-debris exposure in growing children. That uncertainty is not a reassurance — it is precisely why the regulator, when it later allowed a modified device back into use, made a formal post-market study of metal-wear-debris exposure a condition of doing so. So the accurate position is that metallosis is real and common with these rods, and that its long-term meaning is still being actively studied.

Alongside metallosis, the rods have been shown to fail mechanically in several ways. Retrieval studies have documented fracture of the internal locking pin, corrosion of the internal mechanism, and failure of the rod to distract — that is, the rod simply stops lengthening as it should, which defeats the entire purpose of the device and can necessitate an unplanned operation to revise it. Cases of actuator (lengthening-pin) fracture have been reported, and single-centre series have described high rates of mechanical failure at two years and beyond. A newer design, marketed as MAGEC X, was introduced partly to address some of these failure modes; retrieval studies suggest the locking-pin fracture rate was lower in the newer design, but they also found new failure modes and, in some analyses, rods producing less lengthening force than the manufacturer's specification. This is the recurring theme of the whole subject: each iteration improves some problems while the fundamental challenge of a small, sealed, load-bearing mechanism working inside a growing child remains difficult.

Because families are often confused or alarmed by what they have read, I want to set out the UK regulatory timeline as accurately as I can, drawn from the official notices of the Medicines and Healthcare products Regulatory Agency (the MHRA). In February 2020 the manufacturer issued a Field Safety Notice warning that, in the MAGEC Model X rod, the actuator end-cap could separate from the housing after implantation, exposing the internal parts and accelerating wear; earlier notices had already covered locking-pin breakage, O-ring seal failure, metal wear debris, and failure to distract. In March 2020 the MHRA issued a Medical Device Alert requiring additional X-ray follow-up. Then, on 1 April 2020, at the MHRA's request, the manufacturer voluntarily suspended supply of all MAGEC systems to the UK, and the MHRA advised that MAGEC rods should not be implanted in the UK until further notice. Crucially — and this is the point families most need to hear — the MHRA explicitly did not recommend prophylactic (routine, precautionary) removal of rods already implanted in children. In March 2021 the European Notified Body suspended the CE certificate for all MAGEC systems, citing gaps in the technical documentation and quality-management system against a background of wear-and-corrosion failures. The CE mark was reinstated in November 2021, but the UK-specific suspension remained in place while the MHRA completed its own assessment, and the manufacturer globally shortened the labelled maximum implantation time. Finally, in early 2024, the UK suspension was lifted for the modified MAGEC X system only — with conditions, including a formal post-market study of metal-wear-debris exposure and a maximum implantation duration of no more than two years. All earlier generations of the device remain suspended and must not be implanted in the UK.

This is the question that most worries families whose child already has a MAGEC rod, so I want to state the current UK position carefully and without alarm. The MHRA has not recommended blanket, precautionary removal of rods that are in place and working. Its guidance is that each child should be assessed individually by the treating specialist team, and that removal is specifically advised in defined situations — for example, if a component is found to be broken, if the rod has stopped lengthening, and at the end of the distraction treatment, where the modern guidance is not to leave the device in place indefinitely simply as an internal brace. Going forward, the current instructions specify that the system should not remain implanted beyond about two years, because the risk of adverse events appears to rise with longer implantation. Children with an existing implant should be kept under regular follow-up with imaging, comparing new X-rays against the early post-operative films, and any concern should be raised promptly with the implanting surgeon. The essential message is that this is a matter for careful, individualised specialist judgement — not for panic, and not for a single blanket rule applied to every child.

I want to be straightforward about my own position. I do not implant magnetically controlled growing rods; the surgical management of early-onset scoliosis with growth-friendly systems is a highly specialised paediatric field, and it belongs with surgeons and units who do this work in volume and who are engaged directly with the ongoing regulatory and research picture. My view of the technology itself is that it represented a genuinely good idea — sparing young children repeated operations — that has proved considerably more difficult in practice than first hoped, with real and well-documented problems of metallosis and mechanical failure, and a regulatory history that reflects exactly those difficulties. None of that means the concept is worthless; it means it is contested, and that families deserve honesty rather than either uncritical enthusiasm or undue alarm. If your child has one of these rods, the most important thing you can do is stay in regular contact with the specialist team looking after them, keep to the imaging follow-up, and ask them directly about anything you have read that worries you.

• —Tang N, et al. World Neurosurg. 2019. Systematic review and meta-analysis: MCGR vs conventional growing rods. PMID 30716487
• —Akbarnia BA, et al. Spine Deform. 2014. Case-matched traditional vs magnetic growing rods at 2 years. PMID 27927412
• —Saarinen AJ, et al. J Bone Joint Surg Am. 2022. Matched MCGR vs traditional rods in severe early-onset scoliosis. PMID 34644282
• —Thakar C, et al. Eur Spine J. 2018. Systematic review of complications: ~44.5% complication, ~33% unplanned revision. PMID 29675673
• —Migliorini F, et al. J Orthop Surg Res. 2022. Systematic review: efficacy with substantial complication/revision burden. PMID 35690867
• —Rushton PRP, et al. Eur Spine J. 2021. Independent multicentre explant database: metallosis in ~79% of cases. PMID 33544222
• —Joyce TJ, et al. Spine. 2018. Explant analysis: titanium wear debris in 100% of rods, O-ring failure in 53%. PMID 28459777
• —Zhang T, et al. Bone Joint J. 2020. Systematic metallosis investigation: elevated metals and chronic inflammation. PMID 32993330
• —Panagiotopoulou VC, et al. Eur Spine J. 2017. Retrieval study: locking-pin fracture linked to corrosion. PMID 28102447
• —Joyce TJ, et al. Spine. 2020. Independent explant data vs manufacturer Urgent Field Safety Notice (locking-pin fracture). PMID 32539289
• —Jones CS, et al. Spine J. 2016. Actuator (lengthening) pin fracture within MCGRs. PMID 26707076
• —Tognini M, et al. Global Spine J. 2024. Comparative retrieval study: MAGEC X pin-fracture rate and new failure modes. PMID 35446173
• —Agarwal A, et al. Spine Surg Relat Res. 2020. FDA MAUDE analysis of device-related complications. PMID 32405561
• —Hothi H, et al. Bone Jt Open. 2022. Survey of UK surgeons on the impact of the CE-certificate suspension. PMID 35172606
• —Tsirikos AI, et al. Med Devices (Auckl). 2020. Narrative review of MCGR safety, efficacy and patient selection. PMID 32256128 REGULATORY SOURCES (MHRA / GOV.UK):
• —MHRA MDA/2020/010: MAGEC System Model X rods — risk of failure in use (Mar 2020).
• —MHRA MDA/2020/011: All MAGEC systems — supply suspended to the UK (Apr 2020).
• —MHRA DSI/2021/007: CE mark suspended for all MAGEC systems (2021).
• —MHRA DSI/2024/002: MAGEC X system — UK suspension lifted with conditions (2024).