A triple minimally invasive surgery combination for subacute osteoporotic lower lumbar vertebral collapse with neurological compromise: a potential alternative to the vertebral corpectomy/expandable cage strategy

Abstract

OBJECTIVE Acute/subacute osteoporotic vertebral collapses (OVCs) in the lower lumbar spine with neurological compromise, although far less well documented than those in the thoracolumbar junction, may often pose greater treatment challenges. The authors clarified the utility of 3 familiar combined techniques of minimally invasive surgery for this condition as an alternative to the corpectomy/expandable cage strategy. METHODS This report included the authors’ first 5 patients with more than 2 years (range 27–48 months) of follow-up. The patients were between 68 and 91 years of age, and had subacute painful L4 OVC with neurological compromise and preexisting lumbar spinal stenosis. The authors’ single-stage minimally invasive surgery combination consisted of the following: step 1, balloon kyphoplasty for the L4 OVC to restore its strength, followed by L4–percutaneous pedicle screw (PPS) placement with patients in the prone position; step 2, tubular lateral lumbar interbody fusion (LLIF) at the adjacent disc space involved with endplate injury, with patients in the lateral position; and step 3, supplemental PPS–rod fixation with patients in the prone position. RESULTS Estimated blood loss ranged from 20 to 72 mL. Neither balloon kyphoplasty–related nor LLIF-related potentially serious complications occurred. With CT measurements at the 9 LLIF levels, the postoperative increases averaged 3.5 mm in disc height and 3.7 mm in bilateral foraminal heights, which decreased by only 0.2 mm and 0 mm at the latest evaluation despite their low bone mineral densities, with a T-score of −3.8 to −2.6 SD. Canal compromise by fracture retropulsion decreased from 33% to 23% on average. As indicated by MRI measurements, the dural sac progressively enlarged and the ligamentum flavum increasingly shrank over time postoperatively, consistent with functional improvements assessed by the physician-based, patient-centered measures. CONCLUSIONS The advantages of this method over the corpectomy/expandable cage strategy include the following: 1) better anterior column stability with a segmentally placed cage, which reduces stress concentration at the cage footplate-endplate interface as an important benefit for patients with low bone mineral density; 2) indirect decompression through ligamentotaxis caused by whole-segment spine lengthening with LLIF, pushing back both the retropulsed fragments and the disc bulge anteriorly and unbuckling the ligamentum flavum to diminish its volume posteriorly; and 3) eliminating the need for segmental vessel management and easily bleeding direct decompressions. The authors’ recent procedural modification eliminated step 3 by performing loose PPS–rod connections in step 1 and their tight locking after LLIF in step 2, reducing to only once the number of times the patient was repositioned.

Can We Rely on Prophylactic Two-Level Vertebral Cement Augmentation in Long-Segment Adult Spinal Deformity Surgery to Reduce the Incidence of Proximal Junctional Complications?

“…Unlike previous studies, our procedures incorporated interbody fusions with MIS-LLIF either with the transpsoas or prepsoas approach at L1-2 through L4-5 in all 29 patients. The interbody fusion in our LLIF procedure involved placement of the 10° lordotic angle titanium cage for the transpsoas LLIF or the 6° lordotic angle PEEK cage for the prepsoas LLIF [ 1 , 2 , 29 ]. We placed the tallest and widest possible implant that spanned the lateral margins of the apophyseal ring bilaterally [ 1 , 2 , 29 ].…”

“…We used previously described techniques for LLIF at L1-2 through L4-5. The patient was placed in the true lateral position facing the side with a more caudal iliac crest [ 28 , 29 ]. With a 5 cm oblique single incision in line with the fibers of the external abdominal oblique muscle along the pen mark on the skin located at the center of the levels to be addressed, we performed a blunt dissection of the 3 abdominal muscle layers followed by developing the retroperitoneal space to identify the psoas muscle.…”

“…We then opened the retractor blades, which were centered over the anterior two-thirds of the disc space as a table-mounted retractor under lateral fluoroscopic guidance. When using the transpsoas approach, an evoked potential analyzing system (NVM5 system; NuVasive, Inc., San Diego, CA, USA) was connected to each dilator, and threshold-based electromyographic monitoring of the lower-limb muscle was used to confirm safe passage of the dilators through the psoas muscle [ 1 , 2 , 29 , 30 ]. A thorough discectomy, performed carefully so as not to violate the subchondral bone of the endplates [ 1 , 2 , 29 , 31 ], included release of the contralateral anulus using a Cobb elevator and placing the widest possible implant that spanned the lateral margins of the apophyseal ring bilaterally to maximize endplate support [ 1 , 2 , 29 , 32 , 33 , 34 ].…”

“…When using the transpsoas approach, an evoked potential analyzing system (NVM5 system; NuVasive, Inc., San Diego, CA, USA) was connected to each dilator, and threshold-based electromyographic monitoring of the lower-limb muscle was used to confirm safe passage of the dilators through the psoas muscle [ 1 , 2 , 29 , 30 ]. A thorough discectomy, performed carefully so as not to violate the subchondral bone of the endplates [ 1 , 2 , 29 , 31 ], included release of the contralateral anulus using a Cobb elevator and placing the widest possible implant that spanned the lateral margins of the apophyseal ring bilaterally to maximize endplate support [ 1 , 2 , 29 , 32 , 33 , 34 ]. We used porous titanium LLIF cages (CoRoent XL Titanium, NuVasive, Inc.) [ 35 ] with a 10° lordotic angle for 25 patients who underwent the transpsoas LLIF surgery and polyether ether ketone (PEEK) cages (Clydesdale; Medtronic Inc., Minneapolis, MN, USA) with a 6° lordotic angle for 4 patients who underwent LLIF with the prepsoas approach [ 36 ].…”

“…Inflating the balloon with radiopaque contrast under fluoroscopic control created a cavity within the osteoporotic vertebral body. We then introduced PMMA cement of an optimal viscosity into the void under imaging surveillance, watching for cement extravasation beyond the vertebral body margins [ 29 , 43 , 44 , 45 ]. In the UIV, we inserted a guidewire into the vertebral body through the cement introducer immediately after injecting the bone cement, before it hardened.…”