Effect of adding Schroth physiotherapeutic scoliosis specific exercises to standard care in adolescents with idiopathic scoliosis on posture assessed using surface topography: A secondary analysis of a Randomized Controlled Trial (RCT)

Abstract

Background: Adolescent idiopathic scoliosis (AIS) is a three-dimensional structural asymmetry of the spine and trunk affecting 2-4% of adolescents. Standard treatment is observation, bracing, and surgery for small, moderate, and large curves, respectively. Schroth exercises aim to correct posture and reduce curve progression.

Purpose: This study aimed to determine the effect of Schroth exercises added to the standard care compared to standard care alone on torso asymmetry in AIS.

Methods: In a randomized controlled trial (NCT01610908), 124 participants with AIS (age: 10-18, Cobb: 10°-45°, Risser: ≤3) were randomly assigned to the control (Standard care only) or Schroth (Standard care + Schroth treatment) group. Schroth treatment consisted of 1-hour weekly supervised sessions and 30-45 minutes of daily home exercises for six months. The control group received Schroth exercises in the last six months of the 1-year monitoring period. Markerless 3D surface topography assessed torso asymmetry measured by maximum deviation (MaxDev) and root mean square (RMS). Intention to treat linear mixed effects model analysis was compared to the per protocol analysis.

Results: In the intention to treat analysis, the Schroth group (n = 63) had significantly larger decreased RMS (-1.2 mm, 95%CI [-1.5,-0.9]mm, p = 0.012) and MaxDev (-1.9mm, 95%CI [-2.4,-1.5]mm, p = 0.025) measurements compared to controls (n = 57) after six months of intervention. In the per protocol analysis (Schroth n = 39, control n = 36), the Schroth group also had a significantly larger decrease compared to the control in both the RMS (-1.0mm, 95%CI [-1.9, -0.2]mm, p = 0.013) and MaxDev measurements (-2.0mm, 95%CI [-3.3,-0.5]mm, p = 0.037). For the control group, both the intention to treat and per protocol analysis showed no difference in RMS and MaxDev in the last six months of Schroth intervention (p>0.5).

Conclusion: Schroth Exercise treatment added to standard care (observation or bracing) reduced asymmetry measurements in AIS. As expected, a greater effect was observed for participants who followed the prescribed exercise treatment per protocol.

Fig 1. CONSORT flow-chart showing intention to treat and per protocol group sample sizes.

Fig 2. Surface topography procedure.

(a) Alignment of the reflected (gold) and original torso (grey), (b) deviation color map where red reflects area of protrusion and blue to areas of depression relative to the other side, and (c) isolated patch of interest to calculate measurement parameters.

Fig 3. Examples of deviation colour maps, RMS and MaxDev measurements of the largest patch by area over time.

(a) Patient experiencing progression, (b) patient with asymmetry improvement, and (c) no change in asymmetry.

Fig 4. Comparison between groups from intention to treat analysis (mean ± SE).

Comparison of (a) RMS (mm) and (b) MaxDev (mm) outcomes. Linear mixed effects analysis produced the p-value presented.

Fig 5. Comparison between groups from the per protocol analysis (mean ± SE).

Comparison of (a) RMS (mm) and (b) MaxDev (mm) outcomes. Linear mixed effects analysis produced the p-value presented.

Fig 6. Average RMS (mm) and MaxDev (mm) in the group serving as control during the first 6 months and receiving exercises in the last 6 months presented over time from the intention to treat analysis (mean ± SE).

Linear mixed effects analysis produced the p-value presented.

Fig 7. Average RMS (mm) and MaxDev (mm) in the group serving as control during the first 6 months and receiving exercises in the last 6 months presented over time from the per protocol analysis (mean ± SE).

Linear mixed effects analysis produced the p-value presented.