Anterior lumbar interbody fusion: single institutional review of complications and associated variables

Who bleeds during elective anterior lumbar surgery?

Background

Blood loss (BL) during elective anterior lumbar access for interbody fusion or disc replacement is a potentially major complication. This study sought to identify factors other than major vascular injury which contribute to BL and therefore this risk. Factors suggested to effect blood loss include age, increasing body mass index (BMI), sex, prothesis, intraoperative heparinization and continuation of low-dose aspirin (LD-ASA).

Methods

A Cell Saver was used in all cases with BL measured and recorded by an independent autotransfusionist. Heparin was administered intravenously when one or both of 2ndtoe saturation metre signal/s lost pulsatility indicating lower limb arterial flow was interrupted.

Results

The mean age of the 364 patients was 47 ± 13.2 yrs. [95% CI: 45 - 48]; and 191 (52%) were male. Age, BMI and heparinization showed a positive correlation with increased BL. There was no significant association with continuation of low-dose ASA with increased BL. Most patients underwent an ALIF - 265 (72%), 52 (14%) had a TDR, and 47 (13%) had a hybrid operation. There was a significant increase in mean BL between single- and two-level procedures in the non-heparinised group (48 vs 83 mls, p = 0.003). Intraoperative heparinization was administered in 102 patients (28%). The total mean BL for the heparin group (104 ml) which was significantly higher than for the non-heparin group (53 ml) (p = 0.001). Heparinisation did not significantly increase the mean BL in single or double level ALIF patients but did significantly increase the BL in single level TDR (57 vs 151 mls, p = 0.039).

Conclusions

Younger, leaner, non-heparinized, single level ALIF patients represented the lowest bleeding risk in anterior lumbar surgery. Conversely, older, increasing BMI, two operative levels, TDR prosthesis and heparinization represent the highest bleeding risk. Continuation of LD-ASA was not associated with an increase in BL.

Lumbar Lordosis Correction With Transforaminal Lumbar Interbody Fusion in Adult Spinal Deformity Patients with Minimum 2-Year Follow-up

OBJECTIVE

To determine the degree of lumbar lordosis (LL) correction possible via transforaminal lumbar interbody fusion (TLIF) in adult spinal deformity patients.

METHODS

A retrospective chart review identified patients ≥18 years of age with severe positive sagittal balance defined by the SRS-Schwab classification: pelvic incidence to LL mismatch >20°, sagittal vertical axis >9.5cm, and/or pelvic tilt >30°. All patients had surgery between 2013 to 2018 with a TLIF at L4-L5 and/or L5-S1 by the senior author (J.L.F.) with ≥2-years follow-up.

RESULTS

Sixty-one patients (18 men, 43 women) with 85 TLIFs were included with an average age of 66 years and average follow-up of 50 months. Average lumbar lordosis (L1-S1) improved from 27° preoperative to 48° postoperative and 45° at 2-year follow-up (P < 0.001). Average segmental lordosis at L4-L5 TLIF sites improved from 3° preoperative to 13° postoperative and persisted at 2-year follow-up (P < 0.001). Segmental lordosis at L5-S1 TLIF sites improved from 7° preoperative to 21° postoperative and 20° at 2-year follow-up (P < 0.001). Seventeen of the TLIFs (20%) had >20° of segmental lordosis improvement at long-term follow-up. The rate of revision surgery for pseudoarthrosis at the TLIF level was 5%.

CONCLUSIONS

Significant lordosis correction can be achieved through an open TLIF in patients with severe positive sagittal balance when utilizing meticulous deformity correction techniques, avoiding the added morbidity of an anterior approach or a 3-column osteotomy.