Improvement of Spinopelvic Parameters Following the Surgical Treatment of Spondylolisthesis Using Interbody Fusion Cage

There is no consensus regarding the clinical benefit of interbody fusion cage in the treatment of Spondylolisthesis (SL). This study aimed to evaluate the effect of posterolateral fusion combined with interbody fusion cage on the spinopelvic parameters and the pain level of the patients. 

Role of interbody fusion in the treatment of spondylolisthesis 

This prospective study included 40 SL patients who underwent surgery following the failure of conservative management. The Meyerding classification was used to grade SL. Also, the visual analog scale was used to measure the level of pain, before and after the operation. Spinopelvic parameters included total kyphosis, sagittal vertebral axis, pelvic tilt, pelvic incidence, and lumbar lordosis.

The Mean±SD age of the patients was of 53.4±11.6 years. In four patients (10%), SL occurred at two levels. Besides, the etiology was degenerative in 21 cases (52.5%) and isthmic in 19 cases (47.5%). The grade I, II, and III of SL were detected respectively in 17, 17, and 6 cases (42.5%, 42.5%, and 15%, respectively). The Mean±SD preoperative value of the sagittal vertebral axis was 43.1±33.1 mm, which improved to 24.8±22.3 mm after the surgery (P<0.001). Also, the Mean±SD preoperative value of the pelvic tilt significantly improved from 19.2±10º to 17±9.1º (P=0.049). Moreover, the Mean±SD score of the visual analog scale improved from 9.1±0.8 to 2.8±1.2 (P<0.001). The clinical and spinopelvic parameters greatly improved in patients with degenerative SLs, single-level SLs, and the lower grades of SL.

Posterolateral fusion combined with interbody fusion cage improves both the clinical and spinopelvic parameters of SL patients and could be suggested as the treatment of choice for these patients.