Anterior longitudinal ligament release from a posterior approach: an alternative to three-column osteotomy

PURPOSE

Expansion of the anterior column and compression of the posterior column restores lordosis and sagittal imbalance. Anterior longitudinal ligament (ALL) release has been described from lateral and anterior approaches as a technique to improve lumbar lordosis; however, posterior approach to release the ALL has not been adequately assessed.

METHODS

We demonstrate a case series of ALL release using a posterior approach performed in conjunction with posterior column osteotomy (PCO), with or without transforaminal lumbar interbody fusion (TLIF) for spinal deformity. Eleven cases were identified from billing records between 2010 and 2019. Retrospective review was conducted for perioperative complications and revision surgery. Overall and segmental lumbar lordosis (LL) correction was measured from pre- and postoperative imaging.

RESULTS

Eleven patients underwent ALL release with a PCO. Kyphosis, scoliosis, and flat back syndrome were the most common spinal deformities. On average, patients had 9 ± 3 levels fused and a single level ALL release. ALL release was most commonly performed at L1-L2 and L2-L3 levels. An overall LL correction of 28.6° ± 19.8^o was achieved; ALL release introduced 16.7° ± 11.9° of lordotic correction and accounted for 49.2 ± 30.4% of the overall lordotic correction. Average blood loss was 1030 ± 573 mL.

CONCLUSIONS

ALL release as an adjunct to PCO and TLIF is a viable technique for providing increased deformity correction without subjecting the patient to a more invasive three-column osteotomy. While this approach may not be appropriate for all patients, it represents a useful option in spinal deformity correction while limiting blood loss and additional anterior surgery.

LEVEL OF EVIDENCE

IV.

Effect of Surgical Setting on Cost and Hospital Reported Outcomes for Single-Level Anterior Cervical Discectomy and Fusion

BACKGROUND

Hospitals seek to reduce costs and improve patient outcomes by decreasing length of stay (LOS), 30-day all-cause readmissions, and preventable complications. We evaluated hospital-reported outcome measures for elective single-level anterior cervical discectomy and fusions (ACDFs) between tertiary (TH) and community hospitals (CH) to determine location-based differences in complications, LOS, and overall costs.

METHODS

Patients undergoing elective single-level ACDF in a 1-year period were retrospectively reviewed from a physician-driven database from a single medical system consisting of 1 TH and 4 CHs. Adult patients who underwent elective single-level ACDF were included. Patients with trauma, tumor, prior cervical surgery, and infection were excluded. Outcomes measures included all-cause 30-day readmissions, preventable complications, LOS, and hospital costs.

RESULTS

A total of 301 patients (60 TH, 241 CH) were included. CHs had longer LOS (1.25 ± 0.50 versus 1.08 ± 0.28 days, P = .01). There were no differences in complication and readmission rates between hospital settings. CH, orthopaedic subspecialty, female sex, and myelopathy were predictors for longer LOS. Overall, costs at the TH were significantly higher than at CHs ($17 171 versus $11 737; Δ$ = 5434 ± 3996; P < .0001). For CHs, the total costs of drugs, rooms, supplies, and therapy were significantly higher than at the TH. TH status, orthopaedic subspecialty, and myelopathy were associated with higher costs.

CONCLUSION

Patients undergoing single-level ACDFs at CHs had longer LOS, but similar complications and readmission rates as those at the TH. However, cost of ACDF was 1.5 times greater in the TH. To improve patient outcomes, optimize value, and reduce hospital costs, modifiable factors for elective ACDFs should be evaluated.

LEVEL OF EVIDENCE

3.

Evaluation of Risk Factors for Postoperative Urinary Retention in Elective Thoracolumbar Spinal Fusion Patients

STUDY DESIGN

Retrospective case series.

OBJECTIVES

Postoperative urinary retention (POUR) represents a common postoperative complication of all elective surgeries. The aim of this study was to identify demographic, comorbid, and surgical factors risk factors for POUR in patients who underwent elective thoracolumbar spine fusion.

METHODS

Following institutional review board approval, patients who underwent elective primary or revision thoracic and lumbar instrumented spinal fusion in a 2-year period in tertiary and academic institution were reviewed. Sex, age, BMI, preoperative diagnosis, comorbid conditions, benign prostatic hyperplasia, diabetes, primary or revision surgery status, narcotic use, and operative factors were collected and analyzed between patients with and without POUR.

RESULTS

Of the 217 patients reviewed, 54 (24.9%) developed POUR. The average age for a patient with POUR was 67 ± 9, as opposed to 59 ± 10 for those without (P < .0001). Single-level fusions were associated with a 0% incidence of POUR, compared with 54.5% in 6 or more levels. The average hospital stay was increased by 1 day for those who had POUR (5.8 ± 3.3 vs 4.9 ± 3.9 days). There was no significant association with other demographic variables, comorbid conditions, or surgical factors.

CONCLUSIONS

POUR was a common complication in our patient cohort, with an incidence of 24.9%. Our findings demonstrate that patients who developed POUR are significantly older and have larger constructs. Patients who developed POUR also had longer in-hospital stays. Although our study supports other findings in the spine literature, more prospective data is needed to define diagnostic criteria of POUR as well as its management.

Effect of Surgical Setting on Hospital-Reported Outcomes for Elective Lumbar Spinal Procedures: Tertiary Versus Community Hospitals

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

As hospital compensation becomes increasingly dependent on pay-for-performance and bundled payment compensation models, hospitals seek to reduce costs and increase quality. To our knowledge, no reported data compare these measures between hospital settings for elective lumbar procedures. The study compares hospital-reported outcomes and costs for elective lumbar procedures performed at a tertiary hospital (TH) versus community hospitals (CH) within a single health care system.

METHODS

Retrospective review of a physician-maintained, prospectively collected database consisting of 1 TH and 4 CH for 3 common lumbar surgeries from 2015 to 2016. Patients undergoing primary elective microdiscectomy for disc herniation, laminectomy for spinal stenosis, and laminectomy with fusion for degenerative spondylolisthesis were included. Patients were excluded for traumatic, infectious, or malignant pathology. Comparing hospital settings, outcomes included length of stay (LOS), rates of 30-day readmissions, potentially preventable complications (PPC), and discharge to rehabilitation facility, and hospital costs.

RESULTS

A total of 892 patients (n = 217 microdiscectomies, n = 302 laminectomies, and n = 373 laminectomy fusions) were included. The TH served a younger patient population with fewer comorbid conditions and a higher proportion of African Americans. The TH performed more decompressions (P < .001) per level fused; the CH performed more interbody fusions (P = .007). Cost of performing microdiscectomy (P < .001) and laminectomy (P = .014) was significantly higher at the TH, but there was no significant difference for laminectomy with fusion. In a multivariable stepwise linear regression analysis, the TH was significantly more expensive for single-level microdiscectomy (P < .001) and laminectomy with single-level fusion (P < .001), but trended toward significance for laminectomy without fusion (P = .052). No difference existed for PPC or readmissions rate. Patients undergoing laminectomy without fusion were discharged to a facility more often at the TH (P = .019).

CONCLUSIONS

We provide hospital-reported outcomes between a TH and CH. Significant differences in patient characteristics and surgical practices exist between surgical settings. Despite minimal differences in hospital-reported outcomes, the TH was significantly more expensive.

Radiographic Evaluation of Minimally Invasive Instrumentation and Fusion for Treating Unstable Spinal Column Injuries

STUDY DESIGN

Retrospective cohort.

OBJECTIVE

Facet fusion in minimally invasive spine surgery (MISS) may reduce morbidity and promote long-term construct stability. The study compares the maintenance of correction of thoracolumbar (TL) trauma patients who underwent MISS with facet fusion (FF) and without facet fusion (WOFF) and evaluates instrumentation loosening and failure.

METHODS

TL trauma patients who underwent MISS between 2006 and 2013 were identified and stratified into FF and WOFF groups. To evaluate progressive kyphosis and loss of correction, Cobb angles were measured at immediate postoperative, short-term, and long-term follow-up. Evidence of >2 mm of radiolucency on radiographs indicated screw loosening. If instrumentation was removed, postremoval kyphosis angle was obtained.

RESULTS

Of the 80 patients, 24 were in FF and 56 were in WOFF group. Between immediate postoperative and short-term follow-up, kyphosis angle changed by 4.0° (standard error [SE] 1.3°) in the FF and by 3.0° (SE 0.4°) in the WOFF group. The change between immediate postoperative and long-term follow-up kyphosis angles was 3.4° (S.E 1.1°) and 5.2° (S.E 1.6°) degrees in the FF and WOFF groups, respectively. Facet fusion had no impact on the change in kyphosis at short term (P = .49) or long term (P = .39). The screw loosening rate was 20.5% for the 80 patients with short-term follow-up and 68.8% for the 16 patients with long-term follow-up. There was no difference in screw loosening rate. Fifteen patients underwent instrumentation removal-all from the FF group.

CONCLUSION

FF in MISS does not impact the correction achieved and maintenance of correction in patients with traumatic spine injuries.

Comparison of percutaneous minimally invasive versus open posterior spine surgery for fixation of thoracolumbar fractures: A retrospective matched cohort analysis

Introduction

Percutaneous minimally invasive spine surgery (MISS) is a treatment option for thoracolumbar fractures and we aim to evaluate its outcomes.

Methods

A retrospective matched cohort study of all patients with thoracolumbar fractures treated with MISS or open posterior approach.

Results

We included 100 MISS and 155 open patients. After controlling for patient characteristics, our results statistically favor MISS in mean operative time, mean intraoperative blood loss, and number of patients requiring postoperative blood transfusions within 48 h.

Conclusions

Advantages of using MISS for treatment of thoracolumbar fractures are decreased operative time, decreased blood loss, and fewer patients requiring transfusions.

The use of minimally invasive surgery in spine trauma: a review of concepts

Traumatic injuries to the spine can be common in the setting of blunt trauma and delayed diagnosis can have a deleterious effect on patients' health. The goals of treatment in managing spine trauma are prevention of neurological injury, providing stability to the spine, and correcting post-traumatic deformity. Minimally invasive spine surgery (MISS) techniques are an alternative to open spine surgery for treatment of spine fractures. MISS is also a viable treatment in the setting of damage control orthopedics, when patients with multiple traumatic injuries may be unable to tolerate a traditional open approach. MISS techniques have been used in the treatment of unstable fractures with or without spinal cord injury, flexion and extension-distraction injuries, and unstable sacral fractures. Traditional open surgeries have been associated with increased blood loss, longer operative times, and a higher risk for surgical site infection (SSI). MISS techniques have the potential to reduce open approach-associated morbidity, and improve postoperative care and rehabilitation. MISS techniques for spine trauma are an indispensable option in the treatment armamentarium of spine surgeons.

Perineal and Radicular Pain Caused by Contralateral Sacral Nerve Root Schwannoma: Case Report and Review of Literature

BACKGROUND

Sacral schwannomas are very rare nerve sheath tumors. Patients usually present with a variety of nonspecific symptoms, which often lead to a delay in diagnosis. Although most schwannomas are benign, they present surgical challenges owing to their proximity to neurologic and other anatomic structures.

CASE DESCRIPTION

This 58-year-old female presented with a 2-month old history of left-sided perineal and radicular pain secondary to a right S2 sacral nerve root schwannoma. The sacral mass demonstrated homogenous enhancement with cystic changes in a T2-weighted magnetic resonance imaging sequence. The patient underwent S1-S3 laminectomy and tumor excision through a posterior surgical approach. Intraoperative monitoring was used to distinguish nonfunctional tissue during tumor resection. The patient had an unremarkable postoperative course.

CONCLUSIONS

Sacral schwannomas can present with a variety of nonspecific symptoms. They pose unique challenges given their location, size, and involvement of surrounding structures. Complete surgical resection is the main goal of sacral schwannoma treatment. A combined anterior-posterior surgical approach and a multidisciplinary surgical team are associated with improved outcomes.

Allele-Independent Turnover of Human Leukocyte Antigen (HLA) Class Ia Molecules

Major histocompatibility complex class I (MHCI) glycoproteins present cytosolic peptides to CD8+ T cells and regulate NK cell activity. Their heavy chains (HC) are expressed from up to three MHC gene loci (human leukocyte antigen [HLA]-A, -B, and -C in humans), whose extensive polymorphism maps predominantly to the antigen-binding groove, diversifying the bound peptide repertoire. Codominant expression of MHCI alleles is thus functionally critical, but how it is regulated is not fully understood. Here, we have examined the effect of polymorphism on the turnover rates of MHCI molecules in cell lines with functional MHCI peptide loading pathways and in monocyte-derived dendritic cells (MoDCs). Proteins were labeled biosynthetically with heavy water (2H2O), folded MHCI molecules immunoprecipitated, and tryptic digests analysed by mass spectrometry. MHCI-derived peptides were assigned to specific alleles and isotypes, and turnover rates quantified by 2H incorporation, after correcting for cell growth. MHCI turnover half-lives ranged from undetectable to a few hours, depending on cell type, activation state, donor, and MHCI isotype. However, in all settings, the turnover half-lives of alleles of the same isotype were similar. Thus, MHCI protein turnover rates appear to be allele-independent in normal human cells. We propose that this is an important feature enabling the normal function and codominant expression of MHCI alleles.