Review Question - QID 215557

Traditional growing rod (TGR) constructs are associated with greater curve correction and truncal height gains than vertical expandable prosthetic titanium rib (VEPTR) constructs and are associated with significantly fewer complications.

Early-onset scoliosis is defined as scoliosis that presents before 10 years of age and can affect pulmonary development due to truncal shortening. However, early definitive fusion can limit the growth of the thoracic cavity and can lead to a crankshaft phenomenon. Growth-friendly constructs have been developed to allow for gradual expansion of the spine while correcting the spine deformity and improving pulmonary function until the patient has reached skeletal maturity for definitive fusion. TGR constructs have been associated with a greater curve correction, greater truncal height gain, and lower complication rates than VEPTR constructs in large multicenter studies. The presumed reason for this is the subcutaneous positioning of the VEPTR rods compared to the submuscular positioning of the TGR rods leading to implant prominence.

Bachabi et al. performed a multicenter retrospective study of patients with idiopathic early-onset scoliosis treated with TGR or VEPTR. They found a greater initial curve correction (50% vs 27%) and greater thoracic height gain (24% vs 12%) with TGR compared to VEPTR constructs. Additionally, there were significantly lower wound complications in patients treated with TGR constructs and patients with bilateral VEPTR constructs having the highest incidence of complications.

Fedorak et al. reviewed the management of early-onset scoliosis through an instructional course lecture. They discussed non-operative management with Mehta casting that has increased in popularity with several studies reporting a high rate of success with this technique. Operative management consists of growth-friendly constructs, for which the authors discussed magnetically controlled growing rods as a new option with decreased number of open lengthenings. They concluded that conversion of growth-friendly constructs to final fusion is associated with higher rates of complications and revision surgeries.

Incorrect answers
Answer 1: Magnetically controlled growing rods are a relatively new construct that requires fewer surgical lengthenings than traditional growing rod constructs.
Answer 2: Final fusion after a growing rod construct is associated with higher reoperation and complication rates than patients undergoing fusion alone.
Answer 3: There is an increased infection and wound complication risk in patients that undergoing growing rod procedures at a younger age and a longer duration of time between growing rod construct implantation and final fusion.
Answer 5: VEPTR constructs are associated with a significantly higher wound complication rate than traditional growing rod constructs due to the placement in a more subcutaneous position.