Histopathological characteristics of cervical extensor tissue in patients with dropped head syndrome

Nuchal Ligament Reconstruction Surgery for Dropped Head Syndrome: A Case Report

CASE

An 86-year-old woman suffered from dropped head syndrome (DHS). As she was not willing to undergo fusion surgery, we proposed a novel nuchal ligament reconstruction surgery, which is not a direct correction of the malalignment but rather a recovery of the function of extensor muscles under local anesthesia. Twelve months after surgery, the patient remains satisfied and is able to maintain a horizontal gaze.

CONCLUSION

This is the first report regarding a less invasive nuchal ligament reconstruction surgery successfully performed for DHS.

A novel diagnostic examination for dropped head syndrome (DHS) (Prone position cervical extension test; DHS test)

BACKGROUND

Dropped head syndrome (DHS) is followed by severe cervical extension muscle weakness that results in chin-on chest deformity. However, maintaining a neutral cervical position can be temporarily possible, and the diagnosis of DHS might sometimes be difficult. The purpose of the present study is to examine a novel clinical test (DHS test) as the diagnostic utility for objective evaluation that focuses on cervical extension condition in the prone position.

METHODS

One hundred subjects were diagnosed with isolated neck extensor myopathy (INEM)-DHS at our hospital (17 men and 83 women, mean age 75.0 ± 8.5 years), and 62 subjects were enrolled as age-matched controls. The DHS test consisted of three examinations; the first was "Ceiling gazing test" in standing position, the second was horizontal gazing in "Sphinx prone position test", and the third was horizontal gazing in "Hands and knees prone position test". We investigated the sensitivity and specificity of the DHS test for DHS.

RESULTS

The patients showing positive in the INEM-DHS group were 63/100 in Ceiling gaze test, 73/100 in the Sphinx prone position test, and 91/100 in the Hands and knees prone position test. In the control group, 0/62 patients presented positive in the Ceiling gaze test, 4/62 in the Sphinx prone position test, and 0/62 in the Hands and knees prone position test. Sensitivity and specificity of the DHS test were 63.0%/100%, 73.0%/93.5%, and 91.0%/100% in the Ceiling gaze test, Sphinx position prone position test, and Hands and knees prone position test, respectively.

CONCLUSION

The prone position cervical extension test (DHS test) would be useful as a novel objective diagnostic tool for INEM-DHS.

Magnetic resonance imaging findings in patients with dropped head syndrome

BACKGROUND

Dropped head syndrome (DHS) is difficult to diagnose only by clinical examination. Although characteristic images on X-rays of DHS have been studied, changes in soft tissue of the disease have remained largely unknown. Magnetic resonance imaging (MRI) is useful for evaluating soft tissue, and we therefore performed this study with the purpose of investigating the characteristic signal changes of DHS on MRI by a comparison with those of cervical spondylosis.

METHODS

The study involved 35 patients diagnosed with DHS within 6 months after the onset and 32 patients with cervical spondylosis as control. The signal changes in cervical extensor muscles, interspinous tissue, anterior longitudinal ligament (ALL) and Modic change on MRI were analyzed.

RESULTS

Signal changes of cervical extensor muscles were 51.4% in DHS and 6.3% in the control group, those of interspinous tissue were 85.7% and 18.8%, and those of ALL were 80.0% and 21.9%, respectively, suggesting that the frequency of signal changes of cervical extensor muscles, interspinous tissue and ALL was significantly higher in the DHS group (p < 0.05). The presence of Modic change of acute phase (Modic type I) was also significantly higher in the DHS group than in the control group (p < 0.001).

CONCLUSION

MRI findings of DHS within 6 months after the onset presented the characteristic signal changes in cervical extensor muscles, interspinous tissue, ALL and Modic change. Evaluation of MRI signal changes is useful for an objective evaluation of DHS.

Contrast-enhanced Magnetic Resonance Imaging in Patients With Dropped Head Syndrome

STUDY DESIGN

This is a retrospective study of a consecutive case series of dropped head syndrome (DHS).

OBJECTIVE

To identify the characteristic features of contrast-enhanced magnetic resonance imaging (MRI) in DHS patients.

SUMMARY OF BACKGROUND DATA

Isolated neck extensor myopathy DHS is thought to be caused by severe cervical extensor muscle weakness from age-related loss of elasticity. However, the MRI findings of the cervical extensor muscles in DHS patients have not yet been characterized.

MATERIALS AND METHODS

The subjects were 34 patients with isolated neck extensor myopathy DHS who underwent contrast-enhanced MRI within seven months after onset and 32 patients with age-matched cervical spondylosis or cervical soft-tissue tumor as controls. The presence of enhanced findings in the cervical extensor muscles, the involved cervical levels, and the characteristically enhanced shape of those muscles were evaluated using contrast-enhanced MRI.

RESULTS

In the DHS group, the contrast-enhanced MRI showed pronounced enhancement at splenius capitis in 34 cases, rhomboid in 23 cases, semispinalis cervicis in seven cases, and levator scapulae in three cases. In the non-DHS group, none of those extensor muscles were enhanced. The enhanced pattern was butterfly shaped in 29 cases (85.3%) and linear in five cases (14.7%). All were located at the spinous process attachment at C6 or C7 in the DHS group. In the non-DHS group, seven cases presented an enhanced image of the spinous process, with C5-6 in one case, C6 in five cases, and C7 in one case.

CONCLUSIONS

In DHS, contrast-enhanced MRI showed intramuscular enhancement of the cervical extensor muscles, which was not present in non-DHS cases. The enhanced muscles included the splenius capitis muscle in all cases. These findings may be useful for developing a strategy for DHS treatment.

Global Sagittal Spinal Compensation for Dropped Head Alignment

STUDY DESIGN

This is a retrospective radiographic study of a consecutive series of cases in patients with dropped head syndrome (DHS) at a single tertiary referral center.

OBJECTIVE

The aim was to clarify the compensation among parameters of spinal sagittal alignment in patients with DHS.

SUMMARY OF BACKGROUND DATA

The treatment strategy for DHS should vary according to the types of global sagittal spinal alignment. However, theoretical evidence in consideration of spinal sagittal compensation against the dropped head condition is lacking.

MATERIALS AND METHODS

One hundred sixteen patients diagnosed with isolated neck extensor myopathy were enrolled. Radiographic measurements were made, including parameters of spinal sagittal alignment. The patients were divided into three groups according to sagittal spinal balance: C7SVA (sagittal vertical axis) ≥ +50 mm (P-DHS; positive imbalanced DHS), -50 mm ≤C7SVA <+50 mm (B-DHS; balanced DHS), and C7SVA <-50 mm (N-DHS; negative imbalanced DHS). Correlations among the various spinal parameters were analyzed.

RESULTS

Among all types of DHS, there was no correlation between C2-C7 angle (C2-C7A) and T1 slope. In B-DHS, other correlations among the adjacent spinal segments were maintained. In N-DHS, there was no correlation between C2-C7A and TK, and in P-DHS, there was also no correlation between TK and lumbar lordosis.

CONCLUSIONS

The loss of compensation at the cervicothoracic junction was observed in all DHS types. B-DHS showed decompensation only at the cervicothoracic junction. N-DHS presented additional decompensation of the thoracic spine, and P-DHS showed decompensation between the thoracic and lumbar spine. Evaluation of global sagittal spinal balance is important for determining global spinal compensation associated with DHS and when considering treatment strategy.

Association between the Phase Angle and the Severity of Horizontal Gaze Disorder in Patients with Idiopathic Dropped Head Syndrome: A Cross-Sectional Study

Background and Objectives: The phase angle, calculated by bioelectrical impedance analysis, can help elucidate the pathology of patients with idiopathic dropped head syndrome (IDHS) and explain the motor dysfunction associated with the horizontal gaze disorder. The aim of this study was to clarify the characteristics of phase angle in IDHS patients and the relationship between the phase angle and the severity of horizontal gaze disorder. Materials and Methods: This cross-sectional study included 43 female patients with IDHS and 69 healthy female volunteers. A multi-frequency segmental body composition analyzer was used to calculate body composition parameters, including whole-body and lower extremity phase angles. Propensity score (PS) matching analysis was performed to compare the body composition parameters between the IDHS and healthy groups. Variables that determine the PS were identified by correlation analysis, using the whole-body phase angle as the dependent variable. In addition, correlation analysis was performed between the severity of horizontal gaze disorder as assessed by McGregor’s slope (McGS), phase angle, and other body composition parameters. Results: Unadjusted group comparisons showed no significant difference in whole-body and lower extremity phase angles between the IDHS and healthy groups. PS matching created a total of 38 matched pairs for age, height, and fat-free mass index. Although the comparison between groups of matched samples showed no significant difference in the whole-body phase angle, the lower extremity phase angle in the IDHS group was significantly lower than that in the healthy group (p = 0.033). Correlation analysis showed significant negative correlations only between McGS and whole-body (r = −0.31, p = 0.043) and lower extremity phase angle (r = −0.39, p = 0.009) in the IDHS group. Conclusions: Abnormal body composition of the lower extremities were observed in IDHS patients. Furthermore, it was suggested that horizontal gaze disorder in IDHS patients is associated with whole-body and lower extremity phase angles.

Association between the Horizontal Gaze Ability and Physical Characteristics of Patients with Dropped Head Syndrome

Background and Objectives: Patients with dropped head syndrome exhibit weakness of the cervical paraspinal muscles. However, the relationship between horizontal gaze disorder and physical function remains unclear. This study aimed to examine and clarify this relationship. Materials and Methods: Ninety-six patients with dropped head syndrome were included. We measured the McGregor’s Slope and investigated physical characteristics, including cervical muscle strength, back muscle strength, and walking ability. Factor analysis was used to classify the characteristics of physical function, and a linear multiple regression analysis was used to evaluate independent variables explaining the variance in the McGregor’s Slope. The physical functions of DHS patients were classified into three categories by factor analysis: limb and trunk muscle strength, walking ability, and neck muscle strength. Results: The average value of the McGregor’s Slope was 22.2 ± 24.0 degrees. As a result of multiple regression analysis, walking speed (β = −0.46) and apex (β = −0.30) were extracted as significant factors influencing the McGregor’s Slope. Conclusions: Horizontal gaze disorders are not associated with cervical muscle strength but with the walking ability and the alignment type of dropped head syndrome.