Purpose:

Although the functional outcome (e.g. the return to daily activities) plays an important role in the evaluation of treatment success for the paediatric patient, clinicians currently cannot make accurate and objective predictions regarding the very early (≤ 6 weeks) functional outcome and its recovery over time. The purpose of the present study is to objectively measure initial postoperative physical activity levels and examine the relationship with patient characteristics, fusion levels and pain.

Methods:

Step count (SC) was obtained pre- (Pre-Op) and postoperatively (Post-3W: 3 weeks after surgery; Post-6W: 6 weeks after surgery) using an accelerometer. Patients were grouped based on LIV (thoracic (T-group) and lumbar (L-group)) and fusion length (FL ≤ 10 levels = SF-group and FL ≥ 11 levels = LF-group). Differences in the daily SC between groups (LIV and FL) and the three timepoints was investigated using a two-way ANOVA.

Results:

The SC was significantly lower at both Post-3W (p < 0.001) and Post-6W (p < 0.001) compared to the preoperative SC, and significantly (p < 0.001) increased from Post-3W to Post-6W (Pre-Op = 13,049 ± 3214 steps/day; Post-3W = 6486 ± 2925 steps/day; Post-6W = 8723 ± 3020 steps/day). At both post-op timepoints the T-group had a higher SC compared to the L-group.

Conclusion:

A fusion surgery with the LIV at L2 or below has a negative impact on the very early postoperative activity levels. The initial functional outcome level of AIS patients was not related to the presently collected patient characteristics. This suggests that objective activity trackers provide novel information and could have an added value in very early rehabilitation programs.