23. Sacroiliac fusion surgery improves gait patterns of patients with sacroiliac joint dysfunction

Abstract

BACKGROUND CONTEXT The sacroiliac joint (SIJ) is an underappreciated pain generator in 15-30% of patients with low back pain. The SIJ functions as a primary structure which transfers loads of the upper body to the lower extremities. Sacroiliac joint dysfunction (SIJD) is characterized by SIJ laxity with symptoms manifesting primarily as low back and lower extremity pain. Additionally, there is growing evidence that gait patterns may also be affected by SIJD. Although there is still much controversy, minimally invasive sacroiliac fusion (SIF) is gaining interest as a procedure for SIJD patients with unremitting pain. SIF aims to reduce SI pain by stabilizing the SIJ and improving structural support between the sacrum and ilium. While positive outcomes for improved pain and reduced opioid consumption have been associated with SIF, there is a lack of research concerning the effects of SIF on functional biomechanics such as gait performance. PURPOSE To quantify the effects of SIF on biomechanical gait parameters of SIJD patients at three months postoperative follow-up compared to their preoperative state. STUDY DESIGN/SETTING Non-randomized, prospective, concurrent cohort study. PATIENT SAMPLE Twelve symptomatic SIJD patients. OUTCOME MEASURES Spatiotemporal parameters, gait range-of-motion (RoM) parameters, and patient-reported outcomes. METHODS Clinical gait analysis was performed one week before surgery (Pre) and three months after surgery (Post). Each patient performed a series of over-ground gait trials at a comfortable, self-selected speed. Data were collected using a motion capture system and three force plates. Back and leg Visual Analog Scale (VAS), Oswestry Disability Index (ODI), Fear Avoidance Beliefs Questionnaire (FABQ), Tampa Scale for Kinesiophobia (TSK), and Demoralization Scale (DS) scores were also collected at both time points. RESULTS Patients showed increased cadence (Pre: 98.39 vs Post: 106.95 steps/min, p=0.018) and walking speed (Pre: 0.87 vs Post: 1.03 m/s, p=0.013). Patients also showed decreases in stride time (Pre: 1.28 vs Post: 1.14 s, p=0.015), step time (Pre: 0.65 vs Post: 0.58 s, p=0.015), and double-support time (Pre: 0.37 vs Post: 0.29 s, p=0.024). Patients show significant decreases in both knee RoM (Pre: 15.25 vs Post: 10.79°, p=0.02) and head motion (Pre: 4.80 vs Post: 3.18 °, p=0.045) in the coronal plane. VAS leg pain score (Pre: 4.25 vs Post: 2.69, p=0.032) improved significantly postoperatively. CONCLUSIONS SIJD patients treated with SIF showed significant improvements in functional gait and leg pain at their three-month follow-up. The results suggest that SIF provides improved lateral stability which in turn results in more efficient knee motion and improved cadence and step efficiency. The improved leg VAS scores reflect this notion as well. The lack of more pronounced improvements in gait and reported outcomes may be due to insufficient follow-up time to account for a full recovery following SIF. This study may serve as a basis for future diagnostic techniques which utilize gait pattern evaluation as an indicator for early development of SIJD. The findings of this study highlight the impacts that SIJD can have on patients daily lives and reinforces the importance of recognizing the SIJ as a contributor to the functional ability of an individual. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.