Posterior lumbar interbody fusion for aged patients with degenerative spondylolisthesis: is intentional surgical reduction essential?

Background Context: Surgical reduction and posterior lumbar interbody fusion (PLIF) is commonly used to recover segmental imbalance in degenerative spondylolisthesis. However, whether intentional reduction of the slipped vertebra during PLIF is essential in aged patients with degenerative spondylolisthesis remains controversial.

Purpose: We compared the outcomes of surgical reduction and fusion in situ among aged patients who underwent PLIF for degenerative spondylolisthesis.

Study Design: A prospective randomized clinical trial on the surgical treatment of degenerative spondylolisthesis patients aged older than 70 years.

Patient Sample: Between January 2006 and December 2009, 73 patients aged 70 years or older with single-level degenerative spondylolisthesis requiring surgical treatment were included in this study.

Outcome Measures: Clinical outcomes were assessed using the visual analog scale, Oswestry Disability Index, and Japanese Orthopedic Association scores. Radiographic outcomes included percentage of vertebral slippage, focal lordosis, and disc height.

Methods: The 73 patients were randomly assigned to two groups treated using surgical reduction (Group A, n=36) and fusion in situ (Group B, n=37). Both groups were followed up for an average of 33.2 months (range, 24-54 months). The clinical and radiographic outcomes were compared between the two groups.

Results: Surgical complications were similar in the two groups. The average operative time and blood loss during surgery did not insignificantly differ (p>.05) between the two groups. Spondylolisthesis, disc height, and focal lordosis were significantly improved postoperatively in both groups. There was no obvious difference in clinical outcomes, as assessed using the visual analog scale, Oswestry Disability Index, and Japanese Orthopedic Association scores, although the radiographic outcomes were considerably better in Group A than in Group B.

Conclusions: Posterior lumbar interbody fusion with pedicle screws fixation, with or without intraoperative reduction, provides good outcomes in the surgical treatment of aged patients with degenerative spondylolisthesis. Better radiological outcomes by intentional reduction do not necessarily indicate better clinical outcomes.