Microsurgical and Descriptive Three-Dimensional Analysis of the Subarticular Trigone: A Guidemap for Standardizing Lateral Recess Decompression.

Background Lateral recess decompression has remained a cornerstone spinal procedure for decades. Despite its popularity, a significant lack of evidence in the literature exists concerning microsurgical anatomy and pertinent surgical landmarks, resulting in non-standardized nomenclature, descriptions, and surgical approaches. Objective This study provides an in-depth microsurgical and descriptive analysis of the subarticular trigone (SAT), serving as an anatomical guide and a tool to foster consistency in nomenclature and standardization of surgical approaches. Methods We analyzed 35 high-resolution lumbar spine CT scans, employing three-dimensional (3D) processing techniques. The SAT is introduced to delineate the bony prominence enveloping the superiomedial quadrant of the pedicle. The SAT encompasses two zones: (1) a superior zone above the superior pedicular line, corresponding to the medial part of the body of the ascending facet (AF), and (2) an inferior zone between the superior and middle pedicular lines, corresponding to the root of the AF and the medial pars/superior lamina. The superior subarticular point (SSP) and medial subarticular point (MESP) serve as key reference landmarks. The SAT forms the roof of the lateral recess and the region requiring resection during decompression of the traversing root in this anatomical corridor. Various measurements, including SSP and MESP to lateral pars, tip of the facet and spino-laminar junction distance, mean width of the sublaminar ridge (SLR), and percentage of the facet that requires resection for adequate SAT decompression, were carried out. Results The mean distance of the SSP to the lateral pars ranges from 7 to 9.2 mm, to the tip of the descending from 9.3 to 10.1 mm, and to the spino-laminar junction from 6.7 to 8.1 mm. The MESP is located at a mean distance of 5.4-6.9 mm from the medial pedicular line. The mean width of the SLR varies from 18.6 to 29.4 mm. Finally, the percentage of total facet width that needs to be removed to adequately decompress the SAT extends from 32% at L4 to 36% at L1. Conclusions This study presents comprehensive insights into the surgical, descriptive, and correlative anatomy of the lateral recess, emphasizing the SAT. The extrapolated data offer a framework for achieving uniformity in surgical planning and advocate for standardized nomenclature.

Treatment of Chiari Malformation and Concomitant Paediatric Scoliosis Long-Term Follow-Up in One Major Referral Centre in the UK.

OBJECTIVE: Paediatric scoliosis (PS) and Chiari malformation type 1 (CM-1) have been reported to be associated with each other. Scoliosis curvature is a common finding among patients operated for CM-1, and curve development has been related to it. We report a cohort of PS and CM-1 patients managed with posterior fossa and upper cervical decompression (PFUCD) by a single surgeon, with an average of two years of follow-up. METHODS: We present a retrospective cohort in a single referral centre for patients with CM-1 and PS. RESULTS: From 2011 to 2018, we identified fifteen patients with CM-1 and PS; eleven underwent PFUCD, ten had symptomatic CM-1, and one had asymptomatic CM-1 but showed curve progression. The remaining four CM-1 patients were asymptomatic and were hence treated conservatively. The average follow-up post-PFUCD was 26.2 months. Scoliosis surgery was performed in seven cases; six patients underwent PFUCD prior to the scoliosis correction. One scoliosis case underwent surgery in the presence of mild CM-1 treated conservatively. The remaining four cases were scheduled for scoliosis correction surgery, while three were managed conservatively, with one case lost to follow-up. The average time between PFUCD and scoliosis surgery was 11 months. None of the cases had intraoperative neuromonitoring alerts or perioperative neurological complications. CONCLUSION: CM-1 with concomitant scoliosis can be found. Symptomatic CM-1 might require surgery, but as we discovered, PFUCD had negligible effect on curve progression and the future need for scoliosis surgery.

Non-iatrogenic spontaneous acute spinal subdural haematoma after transforaminal lumbar interbody fusion.

PURPOSE: Reporting a rare case of a non-iatrogenic spontaneously resolved spinal subdural haematoma (SSDH) following revision of transforaminal lumbar interbody fusion (TLIF) and its possible explanation. METHODS: Case report of a 40-year-old man with a history of persistent lower back and left lower extremity radicular pain, secondary to recurrent disc prolapse, lumbar spondylosis with foraminal stenosis. He underwent an L5/S1 transforaminal interbody fusion via a right sided approach (through previous lumbar microdiscectomy incision). On post-operative day two, the patient developed headache and photophobia that were discovered to be secondary to an acute thoracolumbar subdural haematoma with no objective neurological deficit. RESULTS: After close observation of his neurological status and conservative management of the subdural haematoma, the patient fully recovered from his symptoms and remained problem-free at 2-year follow-up. CONCLUSIONS: Although the occurrence of acute spinal subdural haematoma after spinal surgery is a rare complication following spinal surgery, its appropriate management relies on early recognition if significant morbidity is to be avoided.

Baastrup's Disease as a Rare Cause of Cauda Equina Syndrome: A Case Report.

CASE: "Baastrup's disease" is a relatively common anatomical condition, controversially recognized as a possible cause of back pain but frequently missed by clinicians of different specialties. We present a rare case of Baastrup's disease causing compression to the cauda equina nerves due to the formation of a large pseudotumoral epidural mass. The patient underwent a successful surgical decompression with remarkable improvement in her neurological presentation. The histopathological findings consisted of increased collagen deposition and chondroid metaplasia. CONCLUSION: Clinicians should be aware of possible cauda equina syndrome in rare cases of Baastrup's disease due to pseudotumoral mass compression in the lumbar spine.

The comparative accuracy and safety of fluoroscopic and navigation-based techniques in cervical pedicle screw fixation: systematic review and meta-analysis.

OBJECTIVE: The goal of this study was to evaluate the comparative accuracy and safety of navigation-based approaches for cervical pedicle screw (CPS) placement over fluoroscopic techniques. METHODS: A systematic search of the literature published between January 2006 and December 2019 relating to CPS instrumentation and the comparative accuracy and safety of fluoroscopic and intraoperative computer-based navigation techniques was conducted. Several databases, including the Cochrane Library, PubMed, and EMBASE, were systematically searched to identify potentially eligible studies. Data relating to CPS insertion accuracy and associated complications, in particular neurovascular complications, were extrapolated from the included studies and summarized for analysis. RESULTS: A total of 17 studies were identified from the search methodology. Eleven studies evaluated CPS placement under traditional fluoroscopic guidance and 6 studies addressed outcomes following navigation-assisted placement (3D C-arm or CT-guided placement). Overall, a total of 4278 screws were placed in 1065 patients. Misplacement rates of CPS were significantly lower (p < 0.0001) in navigation-assisted techniques (12.51% [range 2.5%-20.5%]) compared to fluoroscopy-guided techniques (18.8% [range 0%-43.5%]). Fluoroscopy-guided CPS insertion was associated with a significantly higher incidence of postoperative complications relating to neurovascular injuries (p < 0.038), with a mean incidence of 1.9% compared with 0.3% in navigation-assisted techniques. CONCLUSIONS: This systematic review supports a logical conclusion that navigation-based techniques confer a statistically significantly more accurate screw placement and resultant lower complication rates.

Surgical approaches to L5 corpectomy: a systematic review.

INTRODUCTION: Surgical approaches to pathologies of the L5 vertebra constitute a significant challenge. Our aim was to review the efficacy and safety of the surgical approaches to L5 corpectomy and reconstruction across the range of presenting pathology. MATERIALS AND METHODS: This systematic review was conducted according to PRISMA guidelines, and databases were searched from 1970 to January 2020. The search inclusion criteria were L5 Corpectomy AND/OR Spondylectomy AND/OR Vertebrectomy. The outcome measures studied were length of surgery, blood loss, fusion or failure of fusion/instrumentation, complications and mortality. RESULTS: Initial 36 articles were identified, and final 6 studies met our inclusion criteria. The mean reported blood loss was 2265 ml (400-4700 ml) and was higher for the two-stage posterior-anterior surgery group than the posterior-only surgery group (mean 3230 mls vs. 1260 mls) but not the operative time. All surgical approaches shared high fusion rates (94%) and relatively low complication rates (11.7%). However, surgical strategies incorporating an anterior approach were notable for vascular complications (4-7%), as well as perioperative mortality (9%) not seen in the posterior-only surgery group. CONCLUSION: Where there is clinical and circumstantial equipoise regarding the choice of surgical approaches for a L5 corpectomy, this review indicates a reported mean blood loss of 2265 ml (400-4700 ml), high fusion rates (94%) and relatively low complication rates (11.7%). It is difficult to make direct comparisons between approaches due to small case series, the variability in primary pathology, clinical intent and surgeon experience.

Can MRI findings predict the outcome of cervical spinal cord Injury? a systematic review.

INTRODUCTION: MRI is the established gold standard for imaging acute spinal cord injury (SCI). Our aim was to identify the prognostic value, in terms of neurological outcome, of extradural and intradural features detected on MRI performed acutely following traumatic cervical SCI. MATERIALS AND METHODS: Several databases were systematically searched to identify potentially eligible articles until December 2019. Using a standard PRISMA template, 2606 articles were initially identified. RESULTS: A final 6 full-text articles met the inclusion criteria and were analyzed. An extradural factor, namely the maximal spinal cord compression, was associated with poor neurological outcome and statistically significant (P = 0.02 and P = 0.001 in 2 out of 3 studies). The intradural factors of length of the cord edema (P = 0.001, P = 0.006, and P < 0.001 in 3 studies), intramedullary hemorrhage (P = 0.002, P < 0.001, P < 0.001, and P = 0.002 in 4 studies), and the length of intramedullary hemorrhage (P = 0.028, P = 0.022 in 2 studies) also significantly correlated with poor neurological recovery at follow-up. CONCLUSION: While early MRI is established as a gold standard imaging of acute spinal trauma, it also serves to provide prognostic value on the neurological recovery. From our systematic review, there is a strong association of the extradural finding of maximal spinal cord compression, intradural MRI findings of length of cord edema, intramedullary hemorrhage, and length of intramedullary hemorrhage with neurological recovery in traumatic cervical spinal cord injuries. LEVEL OF EVIDENCE: III.

Selective dorsal rhizotomy for the treatment of severe spastic cerebral palsy: efficacy and therapeutic durability in GMFCS grade IV and V children.

BACKGROUND: Selective dorsal rhizotomy (SDR) has been established as an effective surgical treatment for spastic diplegia. The applicability of SDR to the full spectrum of spastic cerebral palsy and the durability of its therapeutic effects remain under investigation. There are currently limited data in the literature regarding efficacy and outcomes following SDR in Gross Motor Function Classification System (GMFCS) IV and V patients. Intrathecal baclofen has traditionally been the surgical treatment of choice for these patients. When utilised primarily as a treatment for the relief of spasticity, it is proposed that SDR represents a rational and effective treatment option for this patient group. We report our outcomes of SDR performed on children with severe cerebral palsy (GMFCS grade IV and V). The commensurate improvement in upper as well as lower limb spasticity is highlighted. Apparent benefit to urological function following SDR in this patient group is also discussed. METHOD: A retrospective review of prospectively collected data for 54 paediatric patients with severe cerebral palsy (GMFCS IV-V) who received SDR plus specialised physiotherapy. Mean age was 10.2 years (range, 3.0-19.5). SDR guided by electrophysiological monitoring was performed by a single experienced neurosurgeon. All subjects received equivalent physiotherapy. The primary outcome measure was change to the degree of spasticity following SDR. Spasticity of upper and lower limb muscle groups were quantified and standardised using the Ashworth score. Measures were collected at baseline and at 2-, 8- and 14-month postoperative intervals. In addition, baseline and 6-month postoperative urological function was also evaluated as a secondary outcome measure. RESULTS: The mean lower limb Ashworth score at baseline was 3.2 (range, 0-4). Following SDR, significant reduction in lower limb spasticity scores was observed at 2 months and maintained at 8 and 14 months postoperatively (Wilcoxon rank, p < 0.001). The mean reduction at 2, 8 and 14 months was 3.0, 3.2 and 3.2 points respectively (range, 1-4), confirming a sustained improvement of spasticity over a 1-year period of follow-up. Significant reduction in upper limb spasticity scores following SDR was also observed (mean, 2.9; Wilcoxon rank, p < 0.001). Overall, the improvement to upper and lower limb tone following SDR-generally to post-treatment Ashworth scores of 0-was clinically and statistically significant in GMFCS IV and V patients. Urological assessment identified pre-existing bladder dysfunction in 70% and 90% of GMFCS IV and V patients respectively. Following SDR, improvement in urinary continence was observed in 71% of affected GMFCS IV and 42.8% of GMFCS V patients. No serious postoperative complications were identified. CONCLUSIONS: We conclude that SDR is safe and-in combination with physiotherapy-effectively reduces spasticity in GMFCS grade IV and V patients. Our series suggests that spastic quadriplegia is effectively managed with significant improvements in upper limb spasticity that are commensurate with those observed in lower limb muscle groups. These gains are furthermore sustained more than a year postoperatively. In light of these findings, we propose that SDR constitutes an effective treatment option for GMFCS IV and V patients and a rational alternative to intrathecal baclofen.