Correction of dropped head deformity through combined anterior and posterior osteotomies to restore horizontal gaze and improve sagittal alignment

Outcomes of Conservative Versus Surgical Treatment of Dropped Head Syndrome in a Single Institution: A Case Series and Review of the Literature

Dropped head syndrome (DHS), also known as camptocephalia, is characterized by a mobile chin-on-chest deformity from hypotonia of the cervical extensor muscle or hypertonia of the anterior neck muscles. There remains a paucity of quality published literature on this topic, particularly its management. The objective of this study is to identify radiographic and clinical outcomes of surgery as compared to nonsurgical treatment, to summarize the literature, and to create a decision-making paradigm for managing patients with DHS. As such, we report outcomes of our retrospective chart review series as well as a literature review on the etiology, management options, and outcomes. In our series, we examined the radiographic parameters of the C2-C7 Cobb angle, C2-C7 sagittal vertical axis (SVA), and T1 slope, as well as clinically reported outcomes of conservatively managed (CM; N = 8) and surgically managed (SM; N = 5) interventions on 13 patients with DHS at a single institution. At initial presentation, the CM group had poorer C2-C7 Cobb angle (-37.8 ± 3.2 degrees) and C2-C7 SVA (77.1 ± 10.6 mm) in comparison to the SM group (-21.0 ± 30.3 degrees and 56.9 ± 16.2 mm, respectively). We found a statistically significant improvement in the C2-C7 Cobb angle and T1 slope (p-value of 0.024 and 0.019, respectively) after surgery. Clinically, only one patient in the CM group (20%) reported improvement versus six patients in the SM group (80%). Our study is limited by its small sample size, albeit it is the largest cohort of patients treated at a single institution in the United States to our knowledge. Although our cohort was comprised of heterogeneous etiologies and patient comorbidities, we found that surgery can be beneficial in the right patient. To aid in proper surgical selection, we provide an algorithm for workup and management of DHS.

Laminectomy and fusion better maintains horizontal gaze than laminoplasty in cervical spondylotic myelopathy

Background

Laminectomy and fusion (LF) and laminoplasty (LP) are common treatments for cervical spondylotic myelopathy and myeloradiculopathy. While both procedures show similar clinical improvement, LF requires bony fusion while LP offers motion preservation. Cervical sagittal alignment and horizontal gaze maintenance are key outcome measures, but their comparative effects between LF and LP remain unclear. This study evaluated postoperative horizontal gaze and cervical sagittal alignment in patients undergoing either procedure.

Methods

In this retrospective cohort study at 2 academic centers, patients underwent either LF or LP. Pre/postoperative cervical sagittal alignment parameters were collected, including C2-7 lordosis, C2-7 SVA, Occiput-C2 angle, and T1-slope. The McGregor slope measured horizontal gaze, with 8° flexion to 13° extension as normal range. Primary outcome was horizontal gaze maintenance at minimum 1-year follow-up. Secondary outcomes included changes in cervical spine alignment parameters.

Results

Sixty-four patients (30 LF, 34 LP) completed minimum 1-year follow-up. Pre/postoperative sagittal alignment measures showed no significant differences between groups. Within cohorts, LP increased C2-7 sagittal vertical axis (29.1-37.6 mm, p=.04) while LF decreased C2-7 lordosis (11.5°-5.00°, p=.04). Postoperatively, LF showed significantly more optimally aligned patients (90.0%) versus LP (57.8%) (p<.01). Multivariate analysis indicated LP predicted postoperative horizontal gaze malalignment (OR 13.90 [2.10-286.62], p=.022).

Conclusions

While both procedures yielded comparable cervical sagittal alignment outcomes, LF demonstrated superior maintenance of horizontal gaze. These findings suggest that laminectomy and fusion may preserve horizontal gaze better than laminoplasty.Level of Evidence: III.

Dropped head syndrome in a patient with Parkinson's disease and inflammatory myopathy, treated with sternocleidomastoid release and circumferential cervical fusion

BACKGROUND

Dropped head syndrome (DHS) is a recently recognised cause of cervical spinal deformity and disability. The combination of Parkinson's disease (PD) and inflammatory myopathy in the genesis of DHS has not been previously reported. Furthermore, the optimal surgical treatment of progressive DHS remains undefined.

CASE DESCRIPTION

We report the case of a 64-year-old patient with severe DHS and coronal plane deformity secondary to underlying PD, precipitated by a focal paraspinal myositis, successfully corrected using asymmetric sternocleidomastoid (SCM) release and circumferential cervical fusion. The nuances of decision-making in this challenging patient population are highlighted, including the benefits of intraoperative traction, anterior column reconstruction and bicortical screw fixation. Postoperatively, significant reductions in pain and disability were achieved, along with restoration of cervical lordosis (CL), C2-7 sagittal vertical axis (CSVA) and chin-brow vertical angle (CBVA).

CONCLUSIONS

Circumferential cervical fusion with concomitant SCM release is a useful option in the treatment of recalcitrant DHS with biplanar deformity, addressing the unique biomechanical and endocrinological challenges posed by patients with underlying PD.

Dropped Head Syndrome Caused by Thoracolumbar Deformity: A Report of 3 Cases

CASE

We present 3 patients with dropped head syndrome (DHS) caused by thoracolumbar kyphotic deformity who were successfully treated with thoracolumbar corrective surgery only. After the surgery, their symptoms, neck pain, and horizontal gaze difficulty disappeared, and cervical kyphotic alignment was improved indirectly. At the final follow-up, the whole spinal alignment was maintained, and there was no recurrence of symptoms.

CONCLUSION

Surgeons should consider thoracolumbar spine deformity as the possible primary cause of typical DHS symptoms and recognize that thoracolumbar corrective surgery is an effective method for treating DHS patients with thoracolumbar deformity.

K-line in patients with cervical ossification of the posterior longitudinal ligament: relationship with change in sagittal cervical curvature and laminoplasty outcomes

INTRODUCTION

To analyze how K-line is related to change in sagittal cervical curvature and laminoplasty outcomes in patients with cervical ossification of the posterior longitudinal ligament (OPLL).

MATERIALS AND METHODS

The study retrospectively analyzed 81 patients with OPLL who had undergone posterior cervical single-door laminoplasty and arch plate fixation between June 2011 and June 2017. Fifty-five were K-line positive (K[+]) and 26 were K-line negative (K[-]). Clinical and radiological results were compared between the groups. Patients were followed up for at least 2 years.

RESULTS

Before the operation, Japanese Orthopedic Association (JOA) score, visual analogue scale (VAS) score, neck disability index (NDI), and short-form-36 (SF-36) quality of life score did not differ significantly between the groups. Neurological function was improved in both groups after the procedure. At last follow-up, JOA score, VAS score, NDI, SF-36 score, and JOA score improvement rate differed significantly between the groups. Before the operation, at the 3-month and final follow-ups, C2-7 Cobb angle, T1 slope, and C2-7 SVA differed significantly between the groups. The changes were more marked in the K(-) group than in the K(+) group. The incidence of cervical kyphosis differed significantly between the groups (P < 0.05), as well as between patients with lordosis < 7° and those with lordosis ≥ 7°.

CONCLUSIONS

K-line negativity and lordosis < 7° may predict kyphosis after laminoplasty in patients with OPLL. The cervical curvature in patients with OPLL tends towards kyphosis and anteversion after laminoplasty, which contributes to the reduced clinical effect of the procedure.

Radiographic Characteristics of Cervical Deformity (CD) Using a Discriminant Analysis: The Value of Extension Radiographs

STUDY DESIGN

This was a retrospective review of a prospectively collected database.

OBJECTIVE

The aim of this study was to delineate radiographic parameters that distinguish severe cervical spine deformity (CSD).

SUMMARY OF BACKGROUND DATA

Our objective was to define parameters that distinguish severe CSD using a consensus approach combined with discriminant analysis as no system currently exists in the literature.

METHODS

Twelve CSD surgeons reviewed preoperative x-rays from a CSD database. A consensus was reached for categorizing patients into a severe cervical deformity (sCD), non-severe cervical deformity (non-sCD), or an indeterminate cohort. Radiographic parameters were found including classic cervical and spinopelvic parameters in neutral/flexion/extension alignment. To perform our discriminant analysis, we selected for parameters that had a significant difference between the sCD and non-sCD groups using the Student t test. A discriminant function analysis was used to determine which variables discriminate between the sCD versus non-sCD. A stepwise analysis was performed to build a model of parameters to delineate sCD.

RESULTS

A total of 146 patients with cervical deformity were reviewed (60.5±10.5 y; body mass index: 29.8 kg/m2; 61.3% female). There were 83 (56.8%) classified as sCD and 51 (34.9%) as non-sCD. The comparison analysis led to 16 radiographic parameters that were different between cohorts, and 5 parameters discriminated sCD and non-sCD. These parameters were cervical sagittal vertical axis, T1 slope, maximum focal kyphosis in extension, C2 slope in extension, and number of kyphotic levels in extension. The canonical coefficient of correlation was 0.689, demonstrating a strong association between our model and cervical deformity classification. The accuracy of classification was 87.0%, and cross-validation was 85.2% successful.

CONCLUSIONS

More than one third of a series of CSD patients were not considered to have a sCD. Analysis of an initial 17 parameters showed that a subset of 5 parameters can discriminate between sCD versus non-sCD with 85% accuracy. Our study demonstrates that flexion/extension images are critical for defining severe CD.

Management of two patients with dropped head syndrome utilizing anterior-posterior cervical surgery

Background:

Two elderly patients with dropped head syndromes (DHS) were successfully treated with circumferential cervical surgery.

Case Description:

The two patients, respectively, 72 and 53 years of age, both underwent two-staged surgical procedures. The first surgery included the posterior placement of bilateral pedicle screws with multilevel facetectomies, followed by multilevel anterior cervical discectomy/fusion and posterior rod fixation.

Conclusion:

Circumferential decompression/fusion successfully addressed chin on chest deformity in two older patients.

Radiological features of cervical spine in dropped head syndrome: a matched case-control study

PURPOSE

Dropped head syndrome (DHS) is presumably caused by focal myopathy in the cervical posterior muscles; however, distinguishable radiological features of the cervical spine in DHS remain unidentified. This study investigated the radiological features of the cervical spine in dropped head syndrome.

METHODS

The records of DHS patients and age- and sex-matched cervical spondylotic myelopathy (CSM) patients were reviewed. Cervical spinal parameters (C2-7, C2-4, and C5-7 angles) were assessed on lateral cervical spine radiographs. Quantitative radiographic evaluation of cervical spine degeneration was performed using the cervical degenerative index (CDI), which consists of four elements: disk space narrowing (DSN), endplate sclerosis, osteophyte formation, and listhesis.

RESULTS

Forty-one DHS patients were included. Statistically significant differences were noted between the upper and lower cervical spine in the sagittal angle parameters on the neutral, flexion, and extension radiographs in DHS group, whereas no significant differences were observed in CSM group. CDI comparison showed significantly higher scores of DSN in C3/4, C4/5, C5/6, and C6/7; sclerosis in C5/6 and C6/7; and osteophyte formation in C4/5, C5/6, and C6/7 in DHS group than in CSM group. Comparison of listhesis scores revealed significant differences in the upper levels of the cervical spine (C2/3, C3/4, and C4/5) between two groups.

CONCLUSION

Our results demonstrated that the characteristic radiological features in the cervical spine of DHS include lower-level dominant severe degenerative change and upper-level dominant spondylolisthesis. These findings suggest that degenerative changes in the cervical spine may also play a role in the onset and progression of DHS.

Surgical Management of Post-Radiation, Dropped Head Spinal Deformity in Head and Neck Cancer Patients

BACKGROUND

Dropped head syndrome is a morbid condition, which affects daily functionality, causing pain and dysphagia and respiratory compromise. Reported causes of dropped head syndrome include neuromuscular disorders, iatrogenic from cervical spine surgery, idiopathic and post-radiation for head and neck cancers. Management of this spinal disorder remains challenging, as the complication rates are high. We present our series of 7 patients who underwent surgical correction of dropped head syndrome, all resulting from radiation for head and neck cancers.

METHODS

Retrospective review of 7 patients who underwent surgery between 2016 and 2019 for dropped head syndrome secondary to post-radiation cervical spine deformity. Clinical variables were obtained from medical records. Radiographic parameters pre- and post-surgery including T1 slope, sagittal vertical axis, and C2-7 cervical lordosis were examined.

RESULTS

Seven patients were included in the study, with an average age 69 years. Two patients underwent traction pre-operatively. Five patients had posterior fixation and fusion only and two patients had a combined anterior and posterior fixation and fusion. Overall, there was improvement in average pre/post-op SVA (6.96cm to 3.04cm), T1 slope (33.61^o to 24.34^o) and C2-7 lordosis (-21.65^o to -0.03^o).

CONCLUSION

Surgical correction of post-radiation dropped head spinal deformity involving anterior and posterior fixation with osteotomies provides improvement in functional and radiographic outcomes as shown in our series. These cases are technically challenging and have a high rate of peri-operative complications. Approaches must be tailored to the patient with attention to their specific surgical and radiation history.

Medialization of Common Carotid Artery Is Associated with Cervical Kyphosis

Introduction

Reportedly, the medialization of the common carotid artery (MCCA) to be a vascular anomaly with a potential risk of intraoperative carotid artery injury. Nevertheless, among spine surgeons, the presence of MCCA has not been well recognized.

Methods

We retrospectively reviewed consecutive patients who underwent cervical radiographs and magnetic resonance imaging (MRI) examinations in a single spine center. Using MRI, the MCCA grade was classified into grades 1 to 3 in order of severity. Radiographic measurement included C2-C7 angles as cervical lordosis, cervical sagittal vertical axis (C-SVA), T1 slope (T1S), and T1S-cervical lordosis mismatch. We compared each patient's background and radiographic parameters between patients with each of the three MCCA grades. The continuous variables were compared using the Jonckheere-Terpstra trend test and the proportions were compared using the Cochran-Armitage trend test to investigate the trend of variables in three grades.

Results

The present study included data from 133 eligible patients (65 males and 68 females) with a mean age of 63.7 (±14.2) years. The details of MCCA grading were as follows: grade 1, n=101; grade 2, n=27; and grade 3, n=5. With an increasing MCCA grade, age (61.9±14.0, 68.2±13.8, and 76.4±9.4 years for grades 1, 2, and 3, respectively, p=0.005) and proportion of female (p<0.001) had an increasing trend, whereas cervical lordosis had a decreasing trend (11.7±13.5°, 7.0±14.5°, and −10.0±19.2° for grades 1, 2, and 3, respectively, p=0.011).

Conclusions

Several patient backgrounds including the female gender, older age, and kyphotic alignment were determined as MCCA risk factors. Careful preoperative neck vasculature assessment would avoid a catastrophic complication during anterior cervical surgery.

Impact of Spinopelvic sagittal alignment on the surgical outcomes of dropped head syndrome: a multi-center study

Background

Most of the previous studies about the surgical treatment of dropped head syndrome (DHS) are small case series, and their primary outcome measures were cervical alignment parameters. Therefore, little is known about the associations between pre- and postoperative global sagittal alignment in the whole spine and the clinical outcomes of the surgical treatment of DHS. In this study, we investigated the surgical outcomes of DHS, including correction of cervical and global spinal sagittal alignment.

Methods

This study was a retrospective observational study. Fifteen patients with DHS who had undergone correction surgery were enrolled. Surgical outcomes, including complications and implant failures, were investigated. We assessed cervical alignment parameters as well as spinopelvic global alignment parameters, including pelvic incidence (PI), lumbar lordosis (LL), and C7-sacral sagittal vertical axis (SVA). We examined the changes in these parameters using pre- and posoperative whole spine lateral radiographs. The parameters were compared between the failure and nonfailure groups.

Results

Recurrence of sagittal imbalance and horizontal gaze difficulty was observed in 6 cases (40%). In all, 3 cases (20%) exhibited a distal junctional failure and required multiple surgeries with extension of fusion. Of all the radiographic parameters compared between the failure and nonfailure groups, significant differences were only observed in pre and postoperative SVA and PI-LL.

Conclusions

Our results suggest that the global sagittal alignment parameters, including PI-LL and SVA, were different between the patients with failure and non failure, and these parameters might have notable impacts on surgical outcomes. Surgeons should consider PI-LL and SVA while determining the surgical course for patients with DHS.

Dropped Head Syndrome: A Systematic Review

STUDY DESIGN

This study was a systematic review.

OBJECTIVES

To reveal demographic factors, etiologies, response to treatment, and to propose a novel treatment algorithm for dropped head syndrome (DHS).

SUMMARY OF BACKGROUND DATA

DHS is a rare condition defined by weakness of the cervical paraspinal muscles resulting in passively correctable flexion of the cervical spine. Patients present with neck pain, difficulty eating, and impaired horizontal gaze. Because of the rarity of DHS, a paucity of information exists with regard to demographics, etiology, and relative superiority of medical and surgical treatment.

MATERIALS AND METHODS

We conducted a systematic literature review by searching PubMed for "dropped head syndrome," "chin on chest," "isolated neck extensor myopathy" (INEM), and "camptocephalia." Inclusion criteria were English-language articles that applied a specific treatment regimen with outcome data. A binomial logistic regression analysis was then performed to determine which covariates (age, sex, and treatments) were predictive of a positive response to treatment.

RESULTS

A total of 129 patients were described in 74 studies. Mean age was 63.6 and 63% were female. More than two-thirds of all patients fell into just 4 diagnostic categories (isolated neck extensor myopathy, 31.8%; Parkinson's, 20.2%; myasthenia gravis, 12.4%; amyotrophic lateral sclerosis, 7.0%). Overall positive response to treatment was 64.3%; primary medical treatment (73.5%), immune suppression (78.9%), and a combination of both (87.5%). Surgery was 93.8% successful. A treatment algorithm focused on appropriate diagnosis, initial medical management, with surgical evaluation only after failure of medical treatment was proposed.

CONCLUSIONS

Treatment for DHS starts with accurate diagnosis of the underlying etiology and is often associated with neuromuscular disease. A treatment algorithm for appropriate management of these patients was proposed. A trial of medical management and/or immunomodulators is warranted. Failing nonoperative management, surgery is predictive of a positive outcome.

LEVEL OF EVIDENCE

Level V.

Catastrophic Dropped Head Syndrome Requiring Multiple Reconstruction Surgeries after Cervical Laminoplasty

Introduction

Dropped head syndrome (DHS) after cervical laminoplasty (LAMP) is a rare complication, and no etiologies or surgical strategies have been reported. We present a patient who developed catastrophic DHS after LAMP despite having preoperative cervical lordosis that is known to be suitable for LAMP. We describe a hypothesis concerning the possible mechanism responsible for the DHS and a surgical strategy for relieving it.

Case Report

A 76-year-old woman underwent LAMP for cervical spondylotic myelopathy. She achieved satisfactory improvement of neurological symptoms immediately after surgery. However, her neurological symptoms began to gradually deteriorate. She exhibited a dropped head and complained of difficulty maintaining horizontal gaze. Postoperative images showed a focal cervical kyphotic deformity causing anterior shift of the head, and recurrence of spinal cord compression was observed. She underwent additional surgeries for three times, but none of them restored her to baseline status. Retrospectively, the preoperative loading axis of the head existed anteriorly, and she also had a high T1 slope because of rigid thoracic kyphosis. Her preoperative hyper cervical lordosis was compensation for the global spinal malalignment. After LAMP, in accordance with decreases in her cervical lordosis, her head shifted anteriorly. The abnormal lever arm acting on the neck put further stress on the neck extensors, and the overstretched neck extensors possibly no longer generated enough power to raise the head. Uncompensated very high T1 slope because of marked thoracic kyphosis plus invasion of the posterior extensor mechanism by LAMP may have contributed to her catastrophic DHS development.

Conclusions

In the treatment of cervical myelopathy, posterior decompression alone should be applied carefully to elderly patients with cervical sagittal imbalance even if they have apparent cervical lordosis. Once DHS occurs because of cervical sagittal imbalance, normalization of global spinal balance through corrective osteotomy may be indispensable for a successful outcome.