OrthoBuzz occasionally receives posts from guest bloggers. This guest post comes from Impact Science, in response to a recent article in JBJS.
Pain management is an important aspect of postoperative care after posterior spinal fusion for the treatment of adolescent idiopathic scoliosis (AIS). Opioid medications, while highly effective and commonly used for postoperative analgesia, have many well-documented adverse effects. Several recent studies have suggested that dexamethasone, a glucocorticoid, is an effective adjunct for postoperative pain management after many adult orthopaedic procedures, but its use after AIS surgery has not been well studied.
Beginning in 2017, doctors at Children’s Healthcare of Atlanta added dexamethasone to their postoperative pain control pathway for adolescent spinal-fusion patients. In the October 21, 2020 issue of The Journal of Bone & Joint Surgery, Fletcher et al. report findings from a cohort study that investigated the postoperative outcomes of 113 patients (median age of 14 years) who underwent posterior spinal fusion between 2015 and 2018. The main outcome of interest—opioid consumption while hospitalized—was determined by converting all postoperative opioids given into morphine milligram equivalents (MME).
Because dexamethasone entered their institution’s standardized pathway for this operation in 2017, it was easy for the authors to divide these patients into two groups; 65 of the study patients did not receive postoperative steroids, while 48 patients were managed with 3 doses of steroids postoperatively. Relative to the former group, the latter group showed a 39.6% decrease in total MME used and a 29.5% decrease in weight-based MME. Patients who received postoperative dexamethasone were also more likely to walk at the time of initial physical therapy evaluation. Notably, the authors found no differences between the groups with regard to wound dihescence or 90-day infection rates—2 complications that have been associated with chronic use of perioperative steroids.
In commenting on these findings, Amy L. McIntosh, MD from Texas Scottish Rite Hospital for Children writes that she was so impressed that she plans “on adding dexamethasone to our institution’s standardized AIS care pathway.”
Impact Science is a team of highly specialized subject-area experts (Life Sciences, Physical Sciences, Medicine & Humanities), who collaborate with authors, societies, libraries, universities, and various other stakeholders for services to enhance research impact. Through research engagement and science communication, Impact Science aims at democratizing science by making research-backed content accessible to the world.
The tried-and-true treatment for progressive adolescent idiopathic scoliosis (AIS) is a posterior spinal fusion (PSF). However, for skeletally immature patients, there is increasing interest in motion-sparing growth modulation, specifically anterior vertebral body tethering (AVBT). Early reports on tethering looked promising, but the long-term prognosis remains fuzzy.
Newton et al. clarify this somewhat in the May 6, 2020 issue of JBJS. They retrospectively compared outcomes among a cohort of 23 AVBT patients followed for a mean of 3.4 years with those among a matched cohort of 26 PSF patients followed for a mean of 3.6 years. The groups were well-matched in terms of demographics and preoperative curve measurements, but the AVBT group was slightly less skeletally mature based on triradiate cartilage status and Sanders classification.
The authors found that both groups experienced significant postoperative curve correction, but the PSF group had significantly greater immediate correction of the main thoracic curve (78%) than the AVBT group (36%). Smaller immediate correction is to be expected in a growth-modulation procedure, which allows the spine to “grow straighter” over time with the tether. But at the final follow-up, the AVBT group had only a 43% curve correction versus 69% final follow-up correction in the PSF group. In addition, 9 revision procedures occurred in the AVBT group, versus none in the PSF group. Twelve patients (52%) in the AVBT group had evidence of broken tethers, with 3 of those patients undergoing revision surgery due to curve progression linked to tether breakage.
Overall, 12 of 23 patients in the AVBT group (52%) were deemed a “clinical success” at the end of the study (defined as a thoracic curve <35° without a need for a secondary fusion) while all 26 patients in the PSF group were deemed a clinical success. Anterior vertebral body tethering may have a role in the treatment of scoliosis in the growing spine, but the results to date, including these from Newton et al., lead me to question whether the tethering “juice” in its current form is worth the “squeeze.”
Matthew R. Schmitz, MD
JBJS Deputy Editor for Social Media