Faculty Bibliography

Non- missile penetrating spinal injury (NMPSI) is a rare entity in North America and as a result there is no clear treatment paradigm. According to the literature, NMPSI causes serious acute neurological deficits and can also lead to devastating delayed complications in cases of untreated retained foreign bodies (RFB). In this report we present an acute case of NMPSI to the thoracic spine resulting in RFB treated by operative removal using minimally invasive fluoroscopic technique. While in prior published cases of NMPSI operative intervention was accomplished through laminectomy, our case presents an alternative, less invasive approach which may results in shorter recovery time. We also review the literature on NMPSI, including reports on both acute cases and chronic presentation due to RFBs. Based on this review, we conclude that NMPSI associated with RFB should be managed with operative intervention.

OBJECTIVE:Endoscopic discectomy (ED) has been advocated as a less-invasive alternative to open microdiscectomy (OM) and tubular microdiscectomy (TM) for lumbar disc herniations, with the potential to decrease postoperative pain and shorten recovery times. Large-scale, objective comparisons of outcomes between ED, OM, and TM, however, are lacking. The authors' objective in this study was to conduct a meta-analysis comparing outcomes of ED, OM, and TM. METHODS:The PubMed database was searched for articles published as of February 1, 2019, for comparative studies reporting outcomes of some combination of ED, OM, and TM. A meta-analysis of outcome parameters was performed assuming random effects. RESULTS:Twenty-six studies describing the outcomes of 2577 patients were included. Estimated blood loss was significantly higher with OM than with both TM (p = 0.01) and ED (p < 0.00001). Length of stay was significantly longer with OM than with ED (p < 0.00001). Return to work time was significantly longer in OM than with ED (p = 0.001). Postoperative leg (p = 0.02) and back (p = 0.01) VAS scores, and Oswestry Disability Index scores (p = 0.006) at latest follow-up were significantly higher for OM than for ED. Serum creatine phosphokinase (p = 0.02) and C-reactive protein (p < 0.00001) levels on postoperative day 1 were significantly higher with OM than with ED. CONCLUSIONS:Outcomes of TM and OM for lumbar disc herniations are largely equivalent. While this analysis demonstrated that several clinical variables were significantly improved in patients undergoing ED when compared with OM, the magnitude of many of these differences was small and of uncertain clinical relevance, and several of the included studies were retrospective and subject to a high risk of bias. Further high-quality prospective studies are needed before definitive conclusions can be drawn regarding the comparative efficacy of the various surgical treatments for lumbar disc herniations.

Transforaminal endoscopic spine surgery is an emerging technique in spine surgery, but it offers 2 distinct challenges to spine surgeons looking to adopt it: 1) targeting spine pathology and 2) understanding the endoscopic anatomy visualized through the endoscope. Intraoperative computed tomography (CT)-guided navigation is also an emerging technique in spine surgery that is becoming widely adopted for its benefits in assisting surgeons in localizing pathology and guided spine instrumentation placement. In this technical note, we describe a technique that uses intraoperative CT-guided navigation concomitantly with a transforaminal endoscopic approach to decompress a L4-L5 foraminal heterotopic bone formation after an oblique lumbar interbody fusion. The addition of intraoperative CT-guided navigation proved beneficial in targeting the pathology during the procedure and ensuring that the pathology was resolved by offering postoperative CT visualization of the decompressed neural foramen.

Upper lumbar (L1-2, L2-3) disc herniations are distinct in their diffuse presenting clinical symptomatology and have poorer outcomes with surgical intervention than those following mid and lower lumbar disc herniations and disc surgery. The authors present the cases of 3 patients with L1-2 disc herniations and significant stenosis of the spinal canal. The surgical approach used here combined the principles of transforaminal percutaneous endoscopic discectomy and the extreme lateral lumbar interbody fusion procedures with intraoperative CT-guided navigational assistance. The approach provides a safe corridor of direct visualization to the ventral thecal sac with minimal bony resection and could, in principle, reduce neurological injury and biomechanical instability, which likely contribute to poor outcomes at this level.

BACKGROUND:Transforaminal lumbar endoscopic discectomy is a minimally invasive surgical procedure that can be performed in awake patients through an incision less than 1 cm. The procedure requires very little bony removal to access the herniated disc material because the approach is through the foramen, and only a small amount of the superior articulating process is removed to access Kambin's triangle. This study describes our experience with transforaminal endoscopic lumbar decompression (TELD) for the treatment of lumbar disc herniation. We evaluate the risk for reherniation in the first year after surgery and the characteristics of the patients who experience reherniation. METHODS:We describe the technique for the transforaminal endoscopic approach to treat lumbar disc herniations. Retrospectively, a series of 141 consecutive patients, who were operated on with lumbar radiculopathy, was analyzed. We excluded patients who had previous surgery at the lumbar level, surgeries done for disease adjacent to a fusion, and surgeries done for spondylolisthesis. A total of 84 consecutive patients were included who had single level lumbar non-revision surgery and at least 1-year follow up. RESULTS:A series of 46 consecutive male and 38 female patients with an average age of 57.4 years (range, 28-87 years old) who underwent transforaminal endoscopic treatment for lumbar disc herniations between 2014 and 2016 is presented. Four patients required microdiscectomy due to reherniation at 5 months, 8 months, 9 months, and 10 months postoperatively. All the patients in the series improved immediately following their endoscopic procedures, and no patients presented with symptoms suggestive of reherniation until 5 months after their initial endoscopic surgery. Patients with reherniation tended to be young: 31, 45, 48, and 49 years of age: all less than the average patient age who underwent endoscopic surgery. CONCLUSIONS:Transforaminal endoscopic surgical access to lumbar disc herniations is an ultra-minimally invasive approach for the treatment lumbar degenerative disc disease. It allows for neural decompression by removing disc and foraminal pathology with minimal bone removal. This minimal bone removal prevents iatrogenic destabilization. However, the 1-year reherniation rate presented here is 4.7%. This suggests that the benefit of this technique may be that it is ultra-minimally invasive, but it may only be equal, not superior to microdiscectomy in its rate of reherniation.

One complication associated with recombinant human bone morphogenetic protein (rhBMP-2) use in minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) is heterotopic bone growth at the neural foramen which results in the compression of neural structures. Here we present an awake, minimally invasive surgical approach for treating the radiculopathy that results from this excessive bone growth in the foramen. A 42-year-old male underwent a lumbar 4-sacral 1 MIS-TLIF by another surgeon. He did well in the initial postoperative period, but he began to note right leg pain and numbness in an L5 dermatomal pattern. The pain continued for 2 years despite interventional pain management, and he began to note left foot dorsiflexion weakness. An electromyography (EMG) showed a left L5 radiculopathy and a CT Lumbar spine demonstrated excessive bone growth in the right L4-5 neural foramen. The patient underwent an awake, endoscopic foraminotomy procedure utilizing a blunt tipped manual shaver drill system. The patient's radicular symptoms improved immediately, and he remained asymptomatic at the 1 year follow up. Heterotopic foraminal bone growth is one potential complication of rhBMP-2 use in the MIS-TLIF procedure. The endoscopic procedure described here is a minimally invasive surgical option that can be performed in an awake patient and is suggested a unique salvage or rescue procedure to be considered for the treatment of this potential rhBMP-2 complication.

Lumbar total disk replacement is considered for the treatment of lumbar degenerative disk disease with the hope that by preserving motion, the long-term fusion complication of adjacent segment disease can be avoided. The complications of lumbar total disk replacement can be divided into approach-related and long-term complications. Little has been described about the complications and treatment for complications >10 years after the device has been implanted. Here we describe a transforaminal endoscopic diskectomy procedure for a patient presenting with foot drop 12 years after a L5-S1 total disk replacement.

BACKGROUND:Lateral subluxation of the vertebra is commonly seen in degenerative lumbar scoliosis. Transforaminal endoscopic spine surgery is an emerging technique in spine surgery but has never been described as a treatment option for lumbar radiculopathy in the setting of lateral lumbar spondylolisthesis. METHODS:A technique for endoscopic treatment of lumbar disc herniation in the setting of lateral spondylolisthesis is presented. We retrospectively reviewed 199 cases of patients who underwent transforaminal endoscopic surgery in a 3-year period with a minimum follow-up of 1 year. RESULTS:Between 2014 and 2017, 4 patients (average age, 74.8 years; range, 69-82 years) underwent transforaminal endoscopic discectomy procedures for disc herniations at the level of lateral subluxation. One patient whose lateral subluxation was above an instrumented fusion required an extension of fusion to the operated level 5 months after endoscopic surgery for a reherniation. For the other 3 patients, mean visual analog scale score for radicular pain improved from an average pain score of 8.3 before surgery to 3.0 1 year after surgery, and Oswestry Disability Index improved from 26.7 to 4.7. CONCLUSIONS:Transforaminal endoscopic surgery for lumbar disc herniation in the setting of lateral subluxation of vertebral bodies is a unique minimally invasive approach for treatment of lumbar radiculopathy that might be considered as an alternative treatment to deformity correction surgery in older patients.

BACKGROUND:Sacroiliac (SI) joint fusion is considered for the treatment of degenerative sacroiliitis. The procedure has increased in popularity for patients who have exhausted less invasive treatment options since the development of percutaneous SI joint fusion systems. One possible complication of the procedure is a sacral radiculopathy that can result from compression of the S1 nerve by the SI joint fusion implant. Others have described revising the implant by removing it and replacing it with a shorter implant. METHODS:Here we describe a minimally invasive endoscopic S1 nerve root decompression that does not require removing or revising the SI fusion implant. RESULTS:The postoperative course was uneventful, and the patient's radicular pain improved immediately after surgery. Six months after his endoscopic procedure, the patient had no clinical symptoms related to the S1 nerve root compression and was symptomatically improved from her sacroiliac pain. CONCLUSIONS:This technical note is for others to consider as a possible minimally invasive solution for the treatment of lumbar radiculopathy after a minimally invasive SI joint fusion procedure.

OBJECTIVE:To report on intra- and perioperative complications associated with working channel endoscopic spine surgery. METHODS:This study is a retrospective chart review of a multi-institutional patient cohort operated on by surgeons within the Endoscopic Spine Study Group between May 2010 and June 2017. RESULTS:Our study cohort consists of a total of 553 consecutive cases with an average age of 57 years. The most common procedure was an endoscopic discectomy (n = 377, 68%) followed by foraminotomy (n = 156, 28.2%), unilateral laminotomy for bilateral decompression (n = 55, 9.9%), and lateral recess decompression (n = 29, 5.2%). Overall, the rate of intra- and perioperative complications was 2.7%. There were 3 durotomies (0.54%), 2 epidural hematomas (0.36%), 2 patients developed a complex pain disorder (0.36%), 4 recurrent disc herniations within 3 months (1.1%), 4 systemic complications (1.1%), and no wound infections. No risk factors were identified with regards to age, sex, approach, or number of segments. CONCLUSIONS:Endoscopic spine surgery is associated with a favorable rate of intra- and perioperative complications compared with reported rates of minimally invasive ortraditional open spine surgeries. Our report proposes safe and effective strategies for management of these complications.