Improvement in Gait Abnormality Following Minimally Invasive Posterior Sacroiliac Joint Fusion.

Background Sacroiliac joint (SIJ) dysfunction is a common cause of low back pain and associated gait disturbances that result from aberrant muscle activity and symmetry. This study evaluated the magnitude of improvement in gait characteristics in patients with chronic SIJ pain followed for six months after minimally invasive posterior SIJ fusion. Methods This was a single-arm, prospective, pilot study at two private practice orthopedic pain clinics. Gait characteristics were quantitated using a wireless wearable sensor. Ten patients (mean age: 63 ± 12 years) with abnormal SIJ-associated gait impairment were enrolled and underwent posterior SIJ fusion. Results Average gait velocity improved significantly from 69 ± 28.5 cm/sec at baseline to 99.9 ± 31.5 cm/sec at six months, reflecting an overall average improvement of 30.93 cm/sec or 55.4% (p=0.003). Gait speed, variability, and symmetry impairment parameters also improved with corresponding mean percentage improvements at six months of 27.8% (p=0.02), 19.7% (p=0.17), and 11% (p=0.27). A significant decrease in fall risk and increased timed-up-and-go assessments were noted, with improvements of 32.3% and 24.7%, respectively (p=0.004 for both comparisons). Conclusion These pilot findings demonstrate the first objective assessment of gait characteristics in patients with SIJ dysfunction undergoing minimally invasive posterior SIJ fusion.