Name:
10.3171/2022.3.FOCVID2210
Description:
10.3171/2022.3.FOCVID2210
Thumbnail URL:
https://cadmoremediastorage.blob.core.windows.net/95eedb39-7ad4-4936-84ce-98eb3f049b44/videoscrubberimages/Scrubber_254.jpg
Duration:
T00H08M07S
Embed URL:
https://stream.cadmore.media/player/95eedb39-7ad4-4936-84ce-98eb3f049b44
Content URL:
https://asa1cadmoremedia.blob.core.windows.net/asset-6f424ced-da24-4c27-8dba-7ccc70010b58/22-10.mp4
Upload Date:
2023-09-21T08:03:57.8955673Z
Transcript:
Language: EN.
Segment:0 .
[MUSIC PLAYING]
SPEAKER: A 55-year-old man who had undergone previous L1-4 laminectomies and a full course of antibiotics for lumbar osteomyelitis and epidural abscess presented with continued low- back pain and right leg pain, affecting his groin and thigh, as well as gait instability. His symptoms were exacerbated with physical activity and alleviated by elevating his right leg. On examination, he was neurologically intact with full strength, intact sensation to light touch, and preserved gait.
SPEAKER: His standing scoliosis films and CT imaging demonstrated continued osteomyelitis discitis at L3-4, with significant destruction of these vertebral bodies and progressive kyphotic deformity. Based on his symptoms and imaging findings, we offered the patient a minimally invasive lateral retroperitoneal transpsoas approach for L3 and L4 corpectomies, L2-5 interbody fusion, and L2-5 minimally invasive posterior instrumentation.
SPEAKER: Standard operative risks to nearby neural, bowel, or vascular structures applied. And alternative options included anterior corpectomy, posterior fusion without corpectomy, or no surgery. Critical structures to avoid doing the lateral access include the major vasculature and lumbar plexus, as the exiting nerve roots course within and around the psoas muscle and the retroperitoneal space.
SPEAKER: This is aided with use of neuromonitoring throughout the case. L2-5 posterior instrumentation was chosen to safely minimize the construct length and biomechanical disruption. Informed consent was obtained from the patient who wished to proceed. The patient was brought to the operating room where a formal timeout was performed, verifying the correct patient procedure inside.
SPEAKER: General anesthesia was induced and the patient was endotracheally intubated. Neuromonitoring needles were placed in the bilateral lower extremities for electromyography monitoring, motor evoked potentials, and somatosensory evoked potentials. For stage 1 of the procedure, he was positioned in the right lateral decubitus position. An axillary roll was placed.
SPEAKER: His arms were kept outstretched on the appropriate arm boards. He was taped securely to the table with his legs appropriately padded. The table was flexed so as to open up the space between his left 12th rib and iliac crest. Fluoroscopy was used to position the table, such that true AP and lateral images of the spine would be obtained. His L2-L3 and L4-L5 disc spaces were marked on the skin.
SPEAKER: An incision was planned spanning from disc space to disc space. This planned incision was prepped and draped in the usual sterile fashion; local anesthetic was administered. Incision was made with a no. 10 blade scalpel and deeper dissection down to the muscular fascia performed with Bovie cauterization. Once we encountered muscular fascia, it was incised with a scalpel.
SPEAKER: Blunt dissection was performed through the musculature down to the level of the spine. An initial dilator was docked on the L4-5 disc space, and a K-wire was introduced into the disc space. Circumferential stimulation of the initial dilator and the two subsequent demonstrated no nearby neuromonitoring signal. An expandable retractor was placed and a pass probe stimulator used to ensure there were no nearby nerve structures. In this case, the iliac crest was not obstructive to the approach.
SPEAKER: However, patients with a high iliac crest can present a challenge when accessing the L4-5 disc. Breaking the bed to extend the space between the lower rib and iliac crest can improve accessibility, as well as slight angling of the retractor and using angled instruments. Additionally, verifying aorta and IVC locations anterior to the vertebral body and preoperative imaging is critical to the safety of this operation, along with maintenance of a posterior approach during the initial access stage.
SPEAKER: The vessels were not directly visualized in this case. The disc space was bipolar coagulated and incised with the scalpel. Using a variety of disc preparation instruments, including a Cobb elevator, curettes, curved curettes, ring curettes, and rasps, a thorough L4-5 discectomy was performed. The discectomy process was then repeated at L2-3. The dilators were then docked on the center of the L3-4 bony mass.
SPEAKER: Circumferential stimulation did not demonstrate any neuromonitoring signal, and residual psoas muscle on the vertebral bodies was bipolar coagulated and elevated off the bone. Then using osteotomes, L3 and L4 corpectomies were performed by removing the bone piecemeal. Any bony bleeding can be controlled with hemostatic agent and packing, and generally, will cease upon completion of the corpectomy.
SPEAKER: The ALL was left intact. For this stage, initial completion of the upper and lower discectomies is critical to providing reference points for the extent of the operative field. Alternative techniques can include the use of a diamond drill, which improves working hemostasis, however the osteotome is typically faster.
SPEAKER: Intraoperative x-rays provide feedback on the extent of resection and verification of completion when the instrument tips reach the deep portion of the contralateral annulus, as shown here. Calipers were used to determine the appropriate size cage. This titanium expandable cage was fit with 12-degree endplates on either end. The cage was packed with bone morphogenetic protein and morselized allograft and tamped into the corpectomy defect.
SPEAKER: Once it had good experience on AP fluoroscopy, the fluoroscopy machine was turned to the lateral position and the cage was expanded until it was a snug fit and good appearance on fluoroscopy. The locking mechanism was engaged in the corpectomy defect packed with more morselized allograft. This completed the L2-5 interbody fusion. The wound was copiously irrigated and closed in layers with 0 Vicryl sutures in the muscular fascia, 2-0 in the subcutaneous fat, 3-0 in the dermis, and staples in the skin.
SPEAKER: This concluded stage 1 of the procedure. For stage 2 of the procedure, the patient was positioned prone on the Jackson table, compatible with the intraoperative CT scanner. Care was taken to pad all pressure points, including his wrists, elbows, iliac crest, thighs, knees and feet. His back was prepped and draped in the usual sterile fashion, and AP fluoroscopy was used to mark the location of his bilateral L2 and L5 pedicles.
SPEAKER: At each of these locations, a skin incision was made with a scalpel and deeper dissection through the lumbar muscular fascia performed with Bovie cauterization. A Jamshidi needle was cannulated into each pedicle, coursing from lateral to medial using AP fluoroscopy. Once the medial aspect of the pedicle was encountered by each Jamshidi needle, the fluoroscopy machine was turned to the lateral position and the Jamshidi needles were tamped the rest of the way into the vertebral bodies.
SPEAKER: An undersized tap was used to prepare each screw tract over the K-wire and then appropriately sized pedicle screws were placed over the wire. All screws had good purchase. At this point, we performed an intraoperative CT scan. This demonstrated perfect placement of his instrumentation and significant improvement in his lumbar lordosis doses.
SPEAKER: Calipers were used to determine the appropriate length rods. These rods were passed subfascially through the screw extension tabs, and set screws were placed. After confirming good appearance on final AP and lateral fluoroscopy, the set screws were final tightened with the extension tabs broken off. The wounds were copiously irrigated. They were each closed with 0 Vicryl sutures in the fascia, 2-0 Vicryl sutures in the subcutaneous fat, 3-0 in the dermis, and staples in the skin.
SPEAKER: The wounds were dressed sterilely, and the patient returned supine to his stretcher. He tolerated the procedure without apparent complication. At his most recent follow-up 12 months postoperatively, the patient reported 95% improvement in his preoperative symptoms with some back pain but no leg pain. He had full strength on examination with no evidence of instrumentation failure on postoperative films.
SPEAKER: