Objective:
To explore associations of preoperative physical performance with short and long-term postoperative outcomes in patients undergoing lumbar spinal fusion (LSF).
Design:
Retrospective cohort.
Setting:
University hospital.
Population:
Seventy-seven patients undergoing elective LSF were preoperatively screened on: patient demographics, patient reported outcome measures and physical performance measures (movement control, back muscle endurance strength and extensor strength, aerobic capacity and flexibility).
Main outcome measures:
Associations between preoperative variables and inpatient functional recovery, length of hospital stay (LOS) and 1-2 year postoperative pain reduction were explored using random forest analyses assessing the relative influence of the variable on the outcome.
Results:
Aerobic capacity was associated with fast functional recovery < 4 days and prolonged functional recovery > 5 days (median Z-scores = 7.1 and 12.0). Flexibility (median Z-score = 4.3) and back muscle endurance strength (median Z-score = 7.8) were associated with fast functional recovery < 4 days. Maximum back extensor strength was associated with prolonged functional recovery > 5 days (median Z-score = 8.6). Flexibility (median Z-score = 5.1) and back muscle endurance strength (median Z-score= 13.5) were associated with short LOS < 5 days. Aerobic capacity (median Z-score = 8.7) was associated with prolonged LOS > 7 days. Maximum back extensor strength (median Z-score = 3.8) was associated with 1-2 year postoperative pain reduction and aerobic capacity (median Z-score = 2.8) was tentative.
Conclusions:
Physical performance measures were associated with both short and long-term outcomes after LSF. Adding these measures to prediction models predicting outcomes after LSF may increase their accuracy.
Keywords:
aerobic capacity; decision aid; fitness; muscle strength; prediction; random forest.