Empirically derived maximal acceptable wait time for surgery to treat adolescent idiopathic scoliosis

Background

Prioritizing patients using empirically derived access targets can help to ensure high-quality care. Adolescent scoliosis can worsen while patients wait for treatment, increasing the risk of adverse events. Our objective was to determine an empirically derived access target for scoliosis surgery and to compare this with consensus-based targets

Methods

Two-hundred sixteen sequential patients receiving surgery for adolescent idiopathic scoliosis were included in the study. The main outcome was need for additional surgery. Logistic regression modeling was used to evaluate the relation between surgical wait times and adverse events and χ² analysis was used as the primary analysis for the main outcome.

Results

Of the 88 patients who waited longer than six months for surgery, 13 (14.8%) needed additional surgery due to progression of curvature versus 1.6% (2 of 128 patients) who waited less than six months for surgery (χ² analysis, p = 0.0001). Patients who waited longer than six months for surgery had greater progression of curvature, longer surgeries and longer stays in hospital. These patients also had less surgical correction than patients who waited less than six months for surgery (Wilcoxon–Mann–Whitney test, p = 0.011). All patients requiring additional surgeries waited longer than three months for their initial surgery. A receiver–operator characteristic curve also suggested a three-month wait as an access target. The adjusted odds ratio for an adverse event for each additional 90 days of waiting from time of consent was 1.81 (95% confidence interval 1.34–2.44). The adjusted odds ratio increased with skeletal immaturity and with the size of the spinal curvature at the time of consent.

Interpretation

A prolonged wait for surgery increased the risk of additional surgical procedures and other adverse events. An empirically derived access target of three months for surgery to treat adolescent idiopathic scoliosis could potentially eliminate the need for additional surgery by reducing progression of curvature. This is a shorter access target than the six months determined by expert consensus.Adolescent idiopathic scoliosis effects just over 2% of females aged 12–14 years.^1–3 Although only 10% of patients require surgery, spinal instrumentation and fusion for adolescent idiopathic scoliosis is the most common procedure done in pediatric orthopaedics.⁴ Patients who wait too long for scoliosis surgery may require additional surgery such as anterior release to achieve satisfactory correction of the spinal curvature. These patients may also need longer surgeries and may be at increased risk of complications such as increased blood loss, neurologic deficits or inadequate correction of the curvature.^5–14 Furthermore, as seen in other studies of wait times, patients and families can feel anxiety and prolonged suffering while waiting for treatment, which can negatively impact the quality of care.^15–19 Programs such as the Canadian Pediatric Surgical Wait Times Project have determined a maximal acceptable wait time for adolescent scoliosis through expert consensus (similar to how other surgical wait time targets have been determined).²⁰ Surprisingly, there has been little or no attention given to developing evidence-based access targets or maximal acceptable wait times for most treatments.²¹ The purpose of this study was to determine the maximal acceptable wait time for surgical correction of adolescent idiopathic scoliosis using an empirically based approach to minimize the possibility of adverse events related to progression of curvature.