Management of Spinal Deformity in Adult Patients With Neuromuscular Disease

Evaluating the impact of multiple sclerosis on 2 year postoperative outcomes following long fusion for adult spinal deformity: a propensity score-matched analysis

STUDY DESIGN

Retrospective cohort study.

PURPOSE

The impact of neuromuscular disorders such as multiple sclerosis (MS) on outcomes following long segment fusion is underreported. This study evaluates the impact of MS on two-year (2Y) postoperative complications and revisions following ≥ 4-level fusion for adult spinal deformity (ASD).

METHODS

Patients undergoing ≥ 4-level fusion for ASD were identified from a statewide database. Patients with a baseline diagnosis of MS were also identified. Patients with infectious/traumatic/neoplastic indications were excluded. Subjects were 1:1 propensity score-matched (MS to no-MS) based on age, sex and race and compared for rates of 2Y postoperative complications and reoperations. Logistic regression models were utilized to determine risk factors for adverse outcomes at 2Y.

RESULTS

86 patients were included overall (n = 43 per group). Age, sex, and race were comparable between groups (p > 0.05). MS patients incurred higher charges for their surgical visit ($125,906 vs. $84,006, p = 0.007) with similar LOS (8.1 vs. 5.3 days, p > 0.05). MS patients experienced comparable rates of overall medical complications (30.1% vs. 25.6%) and surgical complications (34.9% vs. 30.2%); p > 0.05. MS patients had similar rates of 2Y revisions (16.3% vs. 9.3%, p = 0.333). MS was not associated with medical, surgical, or overall complications or revisions at minimum 2Y follow-up.

CONCLUSION

Patients with MS experienced similar postoperative course compared to those without MS following ≥ 4-level fusion for ASD. This data supports the findings of multiple previously published case series' that long segment fusions for ASD can be performed relatively safely in patients with MS.

Spinal cord injury in high-risk complex adult spinal deformity surgery: review of incidence and outcomes from the Scoli-RISK-1 study

STUDY DESIGN

Clinical case series.

OBJECTIVE

To describe the cause, treatment and outcome of 6 cases of perioperative spinal cord injury (SCI) in high-risk adult deformity surgery.

SETTING

Adult spinal deformity patients were enrolled in the multi-center Scoli-RISK-1 cohort study.

METHODS

A total of 272 patients who underwent complex adult deformity surgery were enrolled in the prospective, multi-center Scoli-RISK-1 cohort study. Clinical follow up data were available up to a maximum of 2 years after index surgery. Cases of perioperative SCI were identified and an extensive case review was performed.

RESULTS

Six individuals with SCI were identified from the Scoli-RISK-1 database (2.2%). Two cases occurred intraoperatively and four cases occurred postoperatively. The first case was an incomplete SCI due to a direct intraoperative insult and was treated postoperatively with Riluzole. The second SCI case was caused by a compression injury due to overcorrection of the deformity. Three cases of incomplete SCI occurred; one case of postoperative hematoma, one case of proximal junctional kyphosis (PJK) and one case of adjacent segment disc herniation. All cases of post-operative incomplete SCI were managed with revision decompression and resulted in excellent clinical recovery. One case of incomplete SCI resulted from infection and PJK. The patient's treatment was complicated by a delay in revision and the patient suffered persistent neurological deficits up to six weeks following the onset of SCI.

CONCLUSION

Despite the low incidence in high-risk adult deformity surgeries, perioperative SCI can result in devastating consequences. Thus, appropriate postoperative care, follow up and timely management of SCI are essential.

A guide to selecting upper thoracic versus lower thoracic uppermost instrumented vertebra in adult spinal deformity correction

PURPOSE

Operative treatment of adult spinal deformity (ASD) has been shown to improve patient health-related quality of life (HRQOL). Selection of the uppermost instrumented vertebra (UIV) in either the upper thoracic (UT) or lower thoracic (LT) spine is a pivotal decision with effects on operative and postoperative outcomes. This review overviews the multifaceted decision-making process for UIV selection in ASD correction.

METHODS

PubMed was queried for articles using the keywords "uppermost instrumented vertebra", "upper thoracic", "lower thoracic", and "adult spinal deformity".

RESULTS

Optimization of UIV selection may lead to superior deformity correction, better patient-reported outcomes, and lower risk of proximal junctional kyphosis (PJK) and failure (PJF). Patient alignment characteristics, including preoperative thoracic kyphosis, coronal deformity, and the magnitude of sagittal correction influence surgical decision-making when selecting a UIV, while comorbidities such as poor body mass index, osteoporosis, and neuromuscular pathology should also be taken in to account. Additionally, surgeon experience and resources available to the hospital may also play a role in this decision. Currently, it is incompletely understood whether postoperative HRQOLs, functional and radiographic outcomes, and complications after surgery differ between selection of the UIV in either the UT or LT spine.

CONCLUSION

The correct selection of the UIV in surgical planning is a challenging task, which requires attention to preoperative alignment, patient comorbidities, clinical characteristics, available resources, and surgeon-specific factors such as experience.

Minimally Invasive Spine Surgery for Kyphoscoliosis in a Patient With Parkinson's Disease: A Case Report

The surgical treatment for severe deformity correction in patients with Parkinson's disease (PD) is usually challenging, requiring lengthy fusions, and with a high risk of postoperative complications. We present a patient with severe kyphoscoliosis and medical history of PD undergoing minimally invasive surgical deformity correction. A 75-year-old female with a 10-year history of medically controlled PD presented at our hospital's outpatient reporting progressive postural changes during the last two years and a half. On clinical examination, we recognized severe kyphoscoliosis associated with Pisa deformity, in the absence of any neurological manifestations. On the initial x-rays, the coronal angulation was 56° in the lumbar area with a significant lateral shift of the trunk, while the right ribs were close to the iliac crest. The patient underwent deformity correction with percutaneous pedicle screws from T5 to S1, a percutaneous transverse process hooks at T5, and transforaminal lumbar interbody fusion at L5-S1. The total duration of the operation was seven hours, and the estimated blood loss was approximately 300 mL. Clinically, the patient's posture improved significantly, alleviating any preoperative compensatory mechanisms such as knee flexion. The postoperative x-rays revealed a very satisfying correction in both the coronal and sagittal planes (20.1 degrees and 26.6 degrees, respectively). Our current case report showed that MIS constitutes a viable alternative for deformity correction in selected patients with PD as part of a multidisciplinary approach. Proper patient selection requires a detailed medical history and a complete neurological and musculoskeletal examination by a dedicated healthcare provider.

Sagittal alignment changes and postoperative complications following surgery for adult spinal deformity in patients with Parkinson's disease: a multi-institutional retrospective cohort study

Background

Parkinson’s disease (PD) has been found to increase the risk of postoperative complications in patients with adult spinal deformity (ASD). However, few studies have investigated this by directly comparing patients with PD and those without PD.

Methods

In this multicenter retrospective cohort study, we reviewed all surgically treated ASD patients with at least 2 years of follow-up. Among them, 27 had PD (PD+ group). Clinical data were collected on early and late postoperative complications as well as any revision surgery. Radiographic parameters were evaluated before and immediately after surgery and at final follow-up, including sagittal vertical axis (SVA), thoracic kyphosis, lumbar lordosis, sacral slope, and pelvic tilt. We compared the surgical outcomes and radiographic parameters of PD patients with those of non-PD patients.

Results

For early complications, the PD+ group demonstrated a higher rate of delirium than the PD− group. In terms of late complications, the rate of non-union was significantly higher in the PD+ group. Rates of rod failure and revision surgery due to mechanical complications also tended to be higher, but not significantly, in the PD+ group (p = 0.17, p = 0.13, respectively). SVA at final follow-up and loss of correction in SVA were significantly higher in the PD+ group.

Conclusion

Extra attention should be paid to perioperative complications, especially delirium, in PD patients undergoing surgery for ASD. Furthermore, loss of correction and rate of non-union were greater in these patients.

Degenerative Adult Cervical Kyphosis With Secondary Diagnosis Codes Are Associated With Higher Cost and Complications After Spinal Fusion: A Medicare Database Study

BACKGROUND

Adult cervical deformity (ACD) is a potentially debilitating condition resulting from kyphosis, scoliosis, or both, of the cervical spine. Conditions such as ankylosing spondylitis, rheumatoid arthritis, Parkinson's disease, and neuromuscular diseases are particularly known to cause severe deformities. We describe the 90-day cost and complications associated with spinal fusion for ACD using International Classification of Diseases (ICD) coding terminology and study if secondary diagnoses associated with potential for severe deformity affect the cost and complication profile of ACD surgery.

METHODS

Medicare data were used to study hospital costs and complications within 90 days after primary cervical fusion for ACD in 2 cohorts matched by demographics and comorbidity burden: (1) patients with diagnoses of secondary pathology (SP) known to cause severe deformity and (2) without SP. Univariate and multiple-variable analyses to study incidence of complications, readmission, and costs within 90 days were done.

RESULTS

A total of 2900 patients in matched cohorts of 1450 each were included. The mean index hospital payment ($26 545 ± $25 968 versus $22 991 ± $21 599) and length of stay (4.8 ± 5.6 versus 3.9 ± 4.5 days) was significantly (P < .01) higher in ACD patients with SP. On adjusted analysis, the risk of procedure-related complications was higher (odds ratio [OR] = 1.47, 95% confidence interval [CI], 1.18-1.83) in patients with SP than those without SP, but not readmission (OR = 1.04, 95% CI, 0.82-1.32) or refusion (OR = 0.95, 95% CI, 0.45-2.0) within 90 days. The cost profile of complications, readmission, and refusion has been given.

CONCLUSIONS

ACD patients with secondary diagnosis codes such as inflammatory arthropathy or neuromuscular pathology incur higher 90-day costs due to the inherent requirement of bigger fusions and higher risk of peri-operative complications, but with similar risk of readmission and refusion as those without SP.

LEVEL OF EVIDENCE

3.

CLINICAL RELEVANCE

With evolving health care reforms and payment models, knowledge of conditions associated with higher expenditure after elective spine surgical procedures will be beneficial to providers and payors for appropriate risk stratification.

Extensive Spinal Fusion Surgery in Patients With Parkinson Disease or Atypical Parkinsonism: Time Course of Clinical Outcomes in 5 Years Progress Report

STUDY DESIGN

A retrospective case series.

OBJECTIVE

To clarify the mid-term results of extensive spinal fusion surgery in patients with Parkinson disease (PD) or atypical Parkinsonism, especially with respect to their activities of daily living (ADL) over time SUMMARY OF BACKGROUND DATA.: Postural disorders associated with PD lead to spinal imbalance and deformity, resulting in significant disabilities. Clinical outcomes of extensive fusion surgeries in patients with PD over a medium-term follow-up period are currently unknown.

METHODS

Patients with PD who underwent extensive fusion surgery more than 5 years prior were included. The patients' backgrounds, surgical and radiographic parameters, perioperative and mechanical complications, and indoor ADL over time were assessed. To assess the activities of severely disabled patients, indoor ADL was classified into four stages: independent; or cane, walker, and wheelchair use.

RESULTS

Twenty-two patients (mean age, 70.6 yrs) were included. The mean blood loss, duration of surgery, and fusion levels were 2039 mL, 424 minutes, and 11.9 levels, respectively. Sagittal vertical axis improved from 220 mm preoperatively to 95 mm postoperatively. Perioperative complications were observed in 17 cases (77%). Before surgery, 1, 5, 12, and four cases were independent in ADL, T-cane, walker, and wheelchair use, respectively, which improved to seven, four, six, and four, respectively in 1 year. Revision surgeries were performed in eight patients (36%) within 3 years of surgery. In the 3 to 5 years after the surgery, the ADL of nine patients worsened due to deterioration of PD. Fifteen cases were followed up over 5 years, at which one, two, four, and seven cases were independent in ADL, cane, walker, and wheelchair use, respectively.

CONCLUSION

Surgical intervention in PD patients with spinal deformities leads to good short-term outcomes; however, the patients' conditions deteriorated because of complications within 3 years and worsening of PD over 3 years after the surgery.

LEVEL OF EVIDENCE

4.

Spinal Fusion in Parkinson's Disease Patients: A Propensity Score-Matched Analysis With Minimum 2-Year Surveillance

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

To compare outcomes and complication rates between patients with and without Parkinson's disease (PD) patients undergoing surgery for adult spinal deformity (ASD).

SUMMARY OF BACKGROUND DATA

There is limited literature evaluating the impact of PD on long-term outcomes after thoracolumbar fusion surgery for ASD.

METHODS

Patients admitted from 2009 to 2011 with diagnoses of ASD who underwent any thoracolumbar fusion procedure with a minimum 2-year follow-up surveillance were retrospectively reviewed using New York State's Statewide Planning and Research Cooperative System. A 1:1 propensity score-match by age, Deyo score, and number of fused vertebral levels was conducted before comparing surgical outcomes of patients with ASD with and without PD. Univariate analysis compared demographics, complications, and subsequent revision. Multivariate binary stepwise logistic regression models identified independent predictors of these outcomes (covariates: age, sex, Deyo Index score, and PD diagnosis).

RESULTS

A total of 576 propensity score-matched patients were identified (PD: n = 288; no-PD: n = 288), with a mean age of 69.7 years (PD) and 70.2 years (no-PD). Each cohort had comparable distributions of age, sex, race, insurance provider, Deyo score, and number of levels fused (all P > 0.05). Patients with PD incurred higher total charges across ASD surgery-related visits ($187,807 vs. $126,610, P < 0.001), yet rates of medical complications (35.8% PD vs. 34.0% no-PD, P = 0.662) and revision surgery (12.2% vs. 10.8%, P > 0.05) were comparable. Postoperative mortality rates were comparable between PD and no-PD cohorts (2.8% vs. 1.4%, P = 0.243). Logistic regression identified nine-level or higher spinal fusion as a significant predictor for an increase in total complications (odds ratio = 5.64); PD was not associated with increased odds of any adverse outcomes.

CONCLUSION

Aside from higher hospital charges incurred, patients with PD experienced comparable overall complication and revision rates to a propensity score-matched patient cohort without PD from the general population undergoing thoracolumbar fusion surgery. These results can support management of concerns and postoperative expectations in this patient cohort.

LEVEL OF EVIDENCE

3.

An N-Ethyl-N-Nitrosourea (ENU) Mutagenized Mouse Model for Autosomal Dominant Nonsyndromic Kyphoscoliosis Due to Vertebral Fusion

Kyphosis and scoliosis are common spinal disorders that occur as part of complex syndromes or as nonsyndromic, idiopathic diseases. Familial and twin studies implicate genetic involvement, although the causative genes for idiopathic kyphoscoliosis remain to be identified. To facilitate these studies, we investigated progeny of mice treated with the chemical mutagen N-ethyl-N-nitrosourea (ENU) and assessed them for morphological and radiographic abnormalities. This identified a mouse with kyphoscoliosis due to fused lumbar vertebrae, which was inherited as an autosomal dominant trait; the phenotype was designated as hereditary vertebral fusion (HVF) and the locus as Hvf. Micro-computed tomography (μCT) analysis confirmed the occurrence of nonsyndromic kyphoscoliosis due to fusion of lumbar vertebrae in HVF mice, consistent with a pattern of blocked vertebrae due to failure of segmentation. μCT scans also showed the lumbar vertebral column of HVF mice to have generalized disc narrowing, displacement with compression of the neural spine, and distorted transverse processes. Histology of lumbar vertebrae revealed HVF mice to have irregularly shaped vertebral bodies and displacement of intervertebral discs and ossification centers. Genetic mapping using a panel of single nucleotide polymorphic (SNP) loci arranged in chromosome sets and DNA samples from 23 HVF (eight males and 15 females) mice, localized Hvf to chromosome 4A3 and within a 5-megabase (Mb) region containing nine protein coding genes, two processed transcripts, three microRNAs, five small nuclear RNAs, three large intergenic noncoding RNAs, and 24 pseudogenes. However, genome sequence analysis in this interval did not identify any abnormalities in the coding exons, or exon-intron boundaries of any of these genes. Thus, our studies have established a mouse model for a monogenic form of nonsyndromic kyphoscoliosis due to fusion of lumbar vertebrae, and further identification of the underlying genetic defect will help elucidate the molecular mechanisms involved in kyphoscoliosis. © 2018 The Authors. JBMR Plus is published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.