Clinical Outcomes and Radiographic Results of Prone Transpsoas Lateral Lumbar Interbody Fusion: A Single-Institution Case Series.

Background and objectives: This study assessed feasibility, radiologic parameters, and clinical outcomes in patients who underwent the prone transpsoas (PTP) approach for lateral lumbar interbody fusion.

Methods: This retrospective observational study included consecutive patients who underwent PTP performed by a single surgeon. Data were collected including age, sex, body mass index, operative levels, retraction time, complications, radiographic measurements, and visual analog scale pain scores. Statistical analyses were performed using nonparametric Wilcoxon 2-sample tests.

Results: A total of 106 consecutive patients (mean [SD] age, 66 [15] years; mean [SD] body mass index, 29.3 [5.0]) underwent PTP on 173 spinal levels, with a mean (SD) follow-up of 13 (8) months. Sixty of 106 (57%) patients underwent a 1-level PTP procedure (range, 1-4 levels), most commonly on L4-5. The mean (SD) retraction time was 10.4 (3.1) minutes for L1-2, 9.7 (2.8) minutes for L2-3, 9.3 (2.3) minutes for L3-4, and 9.5 (3.2) minutes for L4-5. Adverse events included incidental anterior longitudinal ligament release (3 of 173 [2%] levels) and transient ipsilateral hip flexor weakness (1 of 106 [0.9%] patients). The mean pelvic incidence was 57°. Lumbar lordosis increased from a mean of 44° to 51° (P < .001). Pelvic tilt decreased from a mean of 20° to 12° (P < .001). Pelvic incidence-lumbar lordosis mismatch decreased from a mean of 13 to 5 (P < .001). Visual analog scale pain scores improved from a mean of 6 preoperatively to 5 postoperatively (P < .001).

Conclusion: In this single-institution patient series, the PTP approach was effective and safe for lateral lumbar fusion, with minimal complications and improved lumbar lordosis and patient-reported pain outcomes.