Issue No. 45 - June 2012
Magnetically controlled growing rods for severe spinal curvature in young children: a prospective case series
Kenneth Man-Chee Cheung, Jason Pui-Yin Cheung, Dino Samartzis, Kin-Cheung Mak, Yat-Wa Wong, Wai-Yuen Cheung, Behrooz A Akbarnia, Keith Dip-Kei Luk
Comments by Bassel El-Osta
Scoliosis in skeletally immature children is often treated by implantation of a rod to straighten the spine. Rods can be distracted (lengthened) as the spine grows, but patients need many invasive operations under general anaesthesia. Such operations are costly and associated with negative psychosocial outcomes. We assessed the effectiveness and safety of a new magnetically controlled growing rod (MCGR) for non-invasive outpatient distractions.
We implanted the MCGR in five patients, two of whom have now reached 24 months' follow-up. Each patient underwent monthly outpatient distractions. We used radiography to measure the magnitude of the spinal curvature, rod distraction length, and spinal length. We assessed clinical outcome by measuring the degree of pain, function, mental health, satisfaction with treatment, and procedure-related complications.
In the two patients with 24 months' follow-up, the mean degree of scoliosis, measured by Cobb angle, was 67Â° (SD 10Â°) before implantation and 29Â° (4Â°) at 24 months. Length of the instrumented segment of the spine increased by a mean of 1â¢9 mm (0â¢4 mm) with each distraction. Mean predicted versus actual rod distraction lengths were 2â¢3 mm (1 2 mm) versus 1â¢4 mm (0â¢7 mm) for patient 1, and 2â¢0 mm (0â¢2 mm) and 2â¢1 mm (0â¢7 mm) versus 1â¢9 mm (0â¢6 mm) and 1â¢7 mm (0â¢8 mm) for patient 2's right and left rods, respectively. Throughout follow-up, both patients had no pain, had good functional outcome, and were satisfied with the procedure. No MCGR-related complications were noted.
The MCGR procedure can be safely and effectively used in outpatient settings, and minimises surgical scarring and psychological distress, improves quality of life, and is more cost-effective than is the traditional growing rod procedure. The technique could be used for non-invasive correction of abnormalities in other disorders.
This is a very advanced study whichÂ we would like to congratulate the writers and the inventors for. It is probably a few steps forward in treating scoliosis in children with minimum invasive multiple surgery, and a very safe way for treating. From the two patients' follow-up, the treatment and results seem remarkable.
On the other hand, as with all new inventions, the study is in an early stage. It was only limited toÂ two patients and we are not aware of any risks and complications. Potentially, this might change the future of implants used in child scoliosis surgery, however we do not know when this would be available worldwide and the cost implications.