The single-position approach to circumferential lumbar fusion is receiving increased attention and support. This minimally invasive procedure obviates the need to stage the anterior and posterior components on separate days or change the patient’s position.
In the “prone-lateral” variation of the procedure, lateral interbody fusion and posterior instrumentation are completed while the patient remains in the prone position. Advantages include no increased threat of gastrointestinal or great vessel injury and no need for a vascular surgeon to provide access.
Andrew J. Schoenfeld, MD, MSc, of the Department of Orthopaedic Surgery at Brigham and Women’s Hospital, Peter G. Passias, MD, of the Departments of Orthopaedic and Neurologic Surgery at New York University, and colleagues are the first to examine longer-term outcomes of the prone-lateral procedure.
In Spine they say patients demonstrated greater degrees of correction within lumbopelvic alignment, fewer complications, shorter hospital stay, and higher likelihood of discharge directly to home compared with patients who had staged procedures.
The team studied 122 consecutively enrolled adults from a single-surgeon database who underwent planned, same-day circumferential thoracolumbar fusion surgery between September 2018 and May 2021:
- 41% underwent a prone-lateral (PL) single-position procedure
- 59% underwent a same-day staged (SDS) procedure (anterior or lateral interbody placement, followed by repositioning of the patient intraoperatively to perform posterior instrumentation)
The cohort was 51% male, the mean age was 61, and the mean Charlson Comorbidity Index was 3.1.
The PL group had a shorter length of stay (3.8 days vs. 4.9 days for the SDS group; P=0.41), which was associated with better results in:
- Estimated blood loss—252 mL vs. 795 mL (P<0.001)
- Operative time—214 minutes vs. 514 minutes (P<0.001)
- Number of levels fused—3.0 vs. 4.0 (P=0.004)
- Likelihood of fusion to the pelvis (OR, 0.2 in the PL group; P<0.001)
- Osteotomy performed—63% vs. 91% of patients (P<0.001)
- Decompression performed—81% vs. 93% of patients (P<0.001)
The two groups did not differ with respect to any medical or neurological complications within 90 days. However, complications per patient were higher for the SDS group (0.65 vs. 0.32; P=0.036) when controlled for age, body mass index, and levels fused.
By two years postoperatively there were no differences in major complications. No patient in the PL group required reoperation versus 4.8% of the SDS group (P=0.040).
PL was better than SDS procedures for correcting pelvic tilt (P=0.033) and the mismatch between pelvic incidence and lumbar lordosis (P=0.012). Moreover, the PL group was twice as likely to improve on relative pelvic version, a component of the Global Alignment and Proportion score that expresses measured sacral slope minus the ideal (OR, 2.3; P=0.003).
Patients completed questionnaires about their health-related quality of life at baseline and multiple follow-up time points up to two years: the Numeric Rating Scale (NRS), EQ-5D 5-item questionnaire, Short Form-36, Oswestry Disability Index, and Scoliosis Research Society-22r. After controlling for age and levels fused, the PL group had greater improvement in NRS-Back (−6.0 vs. −3.3; P=0.031).
Benefits for Patients and Healthcare Systems
PL surgery should be attractive to patients because its outcomes are comparable to those of SDS procedures with reduced operative time and less intensive rehabilitation. The enhanced efficiency of the PL technique may also translate into financial savings for healthcare systems, especially if future studies show it reduces the need for intensive care, intensive rehabilitation, readmission, and reoperation.