Aims

The aim of this study was to compare the outcomes of surgery using growing rods in patients with severe versus moderate early-onset scoliosis (EOS).

The magnetically controlled growing rod (MCGR) system allows growth maintenance without the risk of anaesthesia, implant and wound complications associated with repeated surgeries. This is a medium-term report of the complications of MCGR from a multicentre study.

Twenty-six patients from 6 spine institutes that are part of a multicentre study with prospectively collected data of minimum 24 months follow-up were assessed. Pre-operative, immediate post-operative and most recent spine radiographs were reviewed to measure the Cobb angle and the rod lengthening distance. The causes and any associated risk factors for re-operations were examined.

Eleven patients required re-operation within the follow-up period, with a mean time to re-operation of 17 months after the initial surgery. Five were due to failure of rod distractions; 3 were due to failure of proximal foundation implants; 2 were due to rod breakage; and one case of superficial wound infection with failure of proximal fixation. Proximal junctional kyphosis occurred in 5 patients. Three had proximal anchor dislodgement and all five constructs were revised.

This is the largest series with the longest follow-up to date. Our series show that the perception that using MCGR may reduce the frequency of re-operations may not be entirely true. This is the first report to examine the need for re-operation after MCGR implantation, and highlights the inherent risks of any surgical treatment in this group of patients despite the advantages of this new implant. Longer-term studies and comparisons with traditional growing rods are required.

We compared the clinical, radiological and quality-of-life outcomes between hybrid and total pedicle screw instrumentation in patients undergoing surgery for neuromuscular scoliosis. A matched comparison using prospectively collected data was undertaken. A total of 66 patients underwent posterior or anteroposterior correction and fusion with hybrid (n = 33, mean age at surgery 15.8 years (9.10 to 19.6)) or total pedicle screw instrumentation (n = 33, mean age 14.7 years (7.0 to 20.7)) with a minimum follow-up of two years. The major curve pre-operatively was a mean of 87° (sd 29, 25° to 141°) and 81° (sd 18, 47° to 116°) in the hybrid and total pedicle screw groups, respectively (p = 0.29) and at a minimum of two years it was 33° (sd 20; 2° to 87°) and 20° (sd 12; 1° to 55°), respectively (p = 0.0016). The mean correction of the major curve was 59% (41% to 88%) in the hybrid and 75% (43% to 99%) in the total pedicle screw groups at two-year follow-up (p = 0.0011). The mean operating time was 7.45 hours (sd 2.18) and 6.04 hours (sd 1.71) in the hybrid and total pedicle screw groups, respectively (p = 0.001), and the mean intra-operative blood loss was 3760 ml (sd 2790) and 1785 ml (sd 1110), respectively (p = 0.001).

Total pedicle screw instrumentation provided shorter operating times, less blood loss and better correction of the major curve compared with hybrid constructs in patients undergoing surgery for neuromuscular scoliosis.