Predictors of clinical and structural outcomes after surgery for spinal nerve sheath tumor resection: a retrospective analysis.

OBJECTIVE: Resection of spinal nerve sheath tumors (SNSTs) typically necessitates laminectomy, often with facetectomy, for adequate exposure of tumor. While removal of bone affords a greater operative window and extent of resection, it places the patient at greater risk for spinal instability. Although studies have identified risk factors for fusion at the time of tumor resection, there has yet to be a study assessing long-term stability following SNST resection. In this study, the authors sought to identify preoperative and operative risk factors that predispose to long-term spinal instability and investigate clinical variables associated with greater risk for subsequent fusion in the time following initial SNST resection. METHODS: An institutional registry of spinal surgeries was queried at a single institution over a 20-year period. Demographic, clinical, and operative variables were recorded retrospectively and investigated for predictive value of several postoperative sequelae. RESULTS: A total of 122 SNST cases among 112 patients were included. At a mean follow-up time of 27.7 months, patients with a history of neurofibromatosis type 2 (NF2) (p = 0.014) and those who had undergone a laminectomy of ≥ 4 levels at the time of initial SNST resection (p = 0.028) were more likely to present with some degree of structural abnormality or neurological deficit following their initial surgery. The presence of facetectomy, degree of laminectomy, and level of spinal surgery were not found to be predictors of future instability. Ultimately, there was no significant predictor for true spinal instability following index surgery without fusion. A secondary analysis showed that an entirely extradural location (p = 0.044) and facetectomy at index surgery (p = 0.012) were predictive of fusion being performed at the time of tumor resection. Four of the 112 patients required fusion after their index SNST resection, 3 of whom underwent fusion for instability at the level of the index surgery. No variables were identified as predictive for future instrumentation. CONCLUSIONS: Ultimately, the authors conclude that resection of SNSTs does not always necessitate fusion, and good outcomes can be obtained with motion-preserving techniques and minimizing facetectomy when possible. Patients with a history of NF2 and those with SNSTs that required ≥ 4-level laminectomy were more likely to exhibit some degree of structural abnormality and/or neurological deficit localized to the index level defined as either new or worsening spinal instability and/or new or worsening neurological deficit at last follow-up; however, no variable was found to be predictive of true spinal instability. Furthermore, a complete facetectomy at initial SNST resection and entirely extradural tumor location were noted to be associated with fusion at index surgery. Lastly, the authors were unable to identify a clinical predictor for future instrumentation.

Does hinge sidedness influence laterality of C5 palsy after expansile open-door cervical laminoplasty?

OBJECTIVE: Cervical expansile open-door laminoplasties (EOLPs) have an open side and a hinge side, with the open side being bridged by grafts or miniplates. The authors explored the possibility that the open-door side might have a greater incidence of C5 palsy due to a greater stretch of the ipsilateral C5 nerve root. METHODS: This study was a retrospective review of prospectively collected data over a period of 25 years specifically assessing surgical complications. Included were patients who underwent EOLP for myelopathy, radiculopathy, or mild central cord injuries (American Spinal Injury Association Impairment Scale [AIS] grade D). Exclusion criteria included preexisting C5 weakness; patients with AIS grade A, B, or C injury; and added instrumentation or additional surgical procedures. Patients were monitored postoperatively for C5 palsy or any other complications. A comparison group included patients who underwent cervical laminectomy and fusion (CLF). RESULTS: A total of 327 laminoplasties were collected, and 31 patients were excluded because of severe spinal cord injury (AIS grades A-C), 3 for preoperative C5 weakness, and 21 for instrumentation or additional surgical procedures. Thus, 272 patients were analyzed with a mean age of 59.9 years (range 22-88 years). Diagnoses at presentation were cervical myelopathy (84.1%), central cord syndrome (7.2%), cervical myeloradiculopathy (3.4%), ossification of the posterior longitudinal ligament (1.9%), and other (3.4%). The most common complications were C5 palsy (n = 7, 2.6%) and wound infection (n = 7, 2.6%). Of the 7 cases of postoperative C5 palsies in this study, 6 occurred on the side of the open door. Of the C5 palsies, 2 were mild, 3 were moderate, and 2 were severe. Two of the 7 C5 palsies had a delayed (> 24 hours) onset. The C5 palsy incidence after CLF was 2.7% with no side preference. CONCLUSIONS: C5 palsy after cervical decompression for myelopathy is a known occurrence, with a rate of 2.6% in the current study. The authors found that C5 palsies more commonly occur on the open side of the laminoplasty. This could be due to a greater manipulation of the nerve root on the side of the open door or greater stretch of the C5 root on the open-door side. If clinical symptoms and anatomical stenosis are symmetric, the authors recommend creating the laminoplasty hinge on the patient's dominant side to minimize potential loss of dominant proximal arm function.

Associations with daily opioid use during hospitalization following lumbar fusion: A contemporary cohort study.

BACKGROUND: Predicting opioid use after lumbar spine fusion remains a challenge. The aim of this study was to identify clinical and demographic parameters that could be associated with opioid use trends during hospitalization after lumbar spine fusion. METHODS: A cohort study of prospective data for all lumbar fusions performed by single surgeon for an 18-month period from 2019 to 2020 was conducted. Univariable and multivariable linear regression analyses were used to assess associations. RESULTS: Amongst the overall cohort of 136 lumbar fusion patients, the mean age was 66.1 ± 10 years, there was an average of 1.7 ± levels treated. Overall, mean opioid use for total stay was 276 ± 360 morphine milligram equivalents (MME), with the greatest amount on postoperative day 1 (POD1) with 81.6 ± 86 MME. Multivariable linear analysis identified older age (-9.9 MME/year; P < 0.01), male gender (-130 MME; P = 0.03) and thoracolumbar interfascial plane (TLIP) block (-144 MME; P = 0.02) all independently were associated with significantly lower opioid use during overall hospitalization. Older age (P < 0.01), POD1 pain in back (P < 0.01), and TLIP use (P < 0.02) also independently were associated significantly lower opioid use on POD1. CONCLUSIONS: Significant reductions in opioid use during hospitalization after lumbar spine fusion were associated with patients that were older, male, and had a TLIP block used. The maximum absolute opioid use was on POD1. We were able to quantify these trends on a daily gradient, which lays the conceptual groundwork to develop personalized algorithms which can model opioid use during hospitalization prior to surgery.

The declining incidence of cervical spine surgery in patients with rheumatoid arthritis: a single-surgeon series and literature review.

OBJECTIVE: With an increasing number of disease-modifying drugs available to manage rheumatoid arthritis (RA), spine surgeons have anecdotally noted decreased rates of cervical spine surgical procedures in this population. Although these medications have been shown to mitigate RA progression and its systemic effects on joint destruction, there are currently no large-scale studies of RA patients that suggest the use of these disease-modifying drugs has truly coincided with a decline in cervical spine surgery. METHODS: Patients with RA who underwent cervical spinal fusion from 1998 to 2021 performed by the senior author were retrospectively reviewed. The cohort was stratified into 3 categories based on procedure level: 1) occipitocervical, 2) atlantoaxial, and 3) subaxial. The number of surgical procedures per year in each subgroup was evaluated to determine treatment trends over time. National (Nationwide) Inpatient Sample (NIS) data on both RA and non-RA patients who underwent cervical fusion were analyzed to assess for surgical trends over time and for differences in likelihood of surgical intervention between RA and non-RA patients over the epoch. RESULTS: From 1998 to 2021, the number of overall cervical fusions performed in RA patients significantly declined (-0.13 procedures/year, p = 0.01) in this cohort, despite an overall significant increase in cervical fusions in non-RA patients over the same period. NIS analysis of cervical fusions across all patients similarly demonstrated a significant increase in cervical fusions over the same epoch (19,278 cases/year, p < 0.0001). When normalized for changes in population size, the incidence of new surgical procedures was lower in patients with RA regardless of surgical technique. Anterior cervical fusion was the most common approach used over the epoch in both RA and non-RA patients; correspondingly, RA patients were significantly less likely to undergo anterior cervical fusion (OR 0.655, 95% CI -0.4504 to -0.3972, p < 0.0001). CONCLUSIONS: At the authors' institution, there was a clear decline in the number of cervical fusions performed to treat the 3 most common forms of cervical spine pathology in RA patients (basilar impression, atlantoaxial instability, and subaxial cervical deformity). Although national trends suggest an increase in total cervical fusions in both RA and non-RA patients, the incidence of new procedures in patients with RA was significantly lower than in patients without RA, which supports the anecdotal results of spine surgeons nationally.

Challenges in sciatic nerve repair: anatomical considerations.

UNLABELLED: OBJECT.: The object of this study was to highlight the challenge of insufficient donor graft material in peripheral nerve surgery, with a specific focus on sciatic nerve transection requiring autologous sural nerve graft. METHODS: The authors performed an anatomical analysis of cadaveric sciatic and sural nerve tissue. To complement this they also present 3 illustrative clinical cases of sciatic nerve injuries with segmental defects. In the anatomical study, the cross-sectional area (CSA), circumference, diameter, percentage of neural tissue, fat content of the sural nerves, as well as the number of fascicles, were measured from cadaveric samples. The percentage of neural tissue was defined as the CSA of fascicles lined by perineurium relative to the CSA of the sural nerve surrounded by epineurium. RESULTS: Sural nerve samples were obtained from 8 cadaveric specimens. Mean values and standard deviations from sural nerve measurements were as follows: CSA 2.84 ± 0.91 mm(2), circumference 6.67 ± 1.60 mm, diameter 2.36 ± 0.43 mm, fat content 0.83 ± 0.91 mm(2), and number of fascicles 9.88 ± 3.68. The percentage of neural tissue seen on sural nerve cross-section was 33.17% ± 4.96%. One sciatic nerve was also evaluated. It had a CSA of 37.50 mm(2), with 56% of the CSA representing nerve material. The estimated length of sciatic nerve that could be repaired with a bilateral sural nerve harvest (85 cm) varied from as little as 2.5 cm to as much as 8 cm. CONCLUSIONS: Multiple methods have been used in the past to repair sciatic nerve injury but most commonly, when a considerable gap is present, autologous nerve grafting is required, with sural nerve being the foremost source. As evidenced by the anatomical data reported in this study, a considerable degree of variability exists in the diameter of sural nerve harvests. Conversely, the percentage of neural tissue is relatively consistent across specimens. The authors recommend that the peripheral nerve surgeon take these points into consideration during nerve grafting as insufficient graft material may preclude successful recovery.