[Diagnosis and treatment of 11 patients with cevical spondylotic amyotrophy].

OBJECTIVE: To explore clinical features, treatment methods and clinical effects of cervical spondylosis with proximal muscular atrophy. METHODS: Eleven patients with proximal-type cervical spondylotic amyotrophy were retrospectively studied from September 2016 to November 2020, including 7 males and 4 females, aged 38 to 68 years old. Clinical symptoms, MRI and neuroelectrophysiological manifestations were analyzed, and patients were treated with conservative treatment or anterior cervical decompression fusion surgery, respectively. The efficacy was evaluated by manual muscle test (MMT) before and after treatment, and patients' satisfaction was followed up at the same time. RESULTS: All patients were followed up for 6 to 19 months. All 11 patients were unilateral, mainly manifested by atrophy of deltoid muscle, supraspinatus muscle and infraspinatus muscle, and may be accompanied by ipsilateral neck and shoulder pain at early stage. MRI showed lesions at C4,5, C5,6 segments were more common. Electrophysiological examination showed the affected muscle was denervated, and amplitude of compound muscle action potential (CMAP) of innervated nerve on the affected side was lower than that on the healthy side. All patients were obtained bone fusion. One patient who were underwent anterior cervical corpectomy and fusion (ACCF) occurred developed contralateral C5 nerve root paralysis after operation, which recovered completely after 10 weeks of symptomatic treatment. At 12 months after operation, the efficacy was evaluated according to MMT, 3 patients were treated conservatively, 2 patients excellent and 1 good;in 8 patients treated by operation, 3 patients were excellent, 4 good, and 1 moderate. CONCLUSION: The incidence of cervical spondylosis with proximal muscular atrophy is low, which is manifested as unilateral proximal muscle atrophy and may be accompanied by ipsilateral neck and shoulder pain in the early stage. Combined with MRI and neuroelectrophysiological examination, misdiagnosis could be reduced. In the early stage of disease, especially in the case of nucleus pulposus protrusion leading to nerve compression, conservative treatment could be taken. When the conservative treatment is ineffective or the pain cannot be tolerated, anterior decompression surgery is recommended, and the overall effect is satisfactory.

Reliability and variability in the interpretation of lumbar high intensity zone.

OBJECTIVE: The aim of this study was to evaluate the reliability of high intensity zone (HIZ) and to assess discrepancy in the interpretation, as well as investigate the effects of parameters of HIZ on interobserver variation. METHODS: Four spine surgeons made independent observations on lumbar magnetic resonance imaging (MRI) from 207 consecutive patients from 3 institutions. The κ statistic was used to characterize inter- and intraobserver reliability for visual assessments of HIZ. The corresponding MRI was provided to 2 additional spine surgeons for quantitative measurements. The parameters of HIZ, including signal intensity (SI) and area ratio (HIZ%), were used to assess the interobserver variation of HIZ. RESULTS: The overall interobserver agreement for visual assessments was substantial (κ=0.62 at L4-5 and 0.61 at L5-S1), and intraobserver agreement was excellent (κ=0.84 at L4-5 and 0.86 at L5-S1). Of 93 observed HIZ, 17 instances (18.3%) were agreed upon by all visual observers. The SI with full agreement was significantly brighter than all the others (p<0.01). The HIZ% with 2 agreements was significantly smaller than those with 4 agreements (p=0.04) and 3 agreements (p=0.03). Although fewer observers with consensus were associated with smaller HIZ%, the difference was not significant (p>0.05). CONCLUSION: The reliability in the interpretation of HIZ was sufficient for spine surgeons with differing levels of experience. This study highlighted that signal intensity was the primary cause of variability in visual observation.

Quantitative estimation of the high-intensity zone in the lumbar spine: comparison between the symptomatic and asymptomatic population.

BACKGROUND CONTEXT: The high-intensity zone (HIZ) on magnetic resonance imaging (MRI) has been studied for more than 20 years, but its diagnostic value in low back pain (LBP) is limited by the high incidence in asymptomatic subjects. Little effort has been made to improve the objective assessment of HIZ. PURPOSE: To develop quantitative measurements for HIZ and estimate intra- and interobserver reliability and to clarify different signal intensity of HIZ in patients with or without LBP. STUDY DESIGN: A measurement reliability and prospective comparative study. PATIENT SAMPLE: A consecutive series of patients with LBP between June 2010 and May 2011 (group A) and a successive series of asymptomatic controls during the same period (group B). OUTCOME MEASURES: Incidence of HIZ; quantitative measures, including area of disc, area and signal intensity of HIZ, and magnetic resonance imaging index; and intraclass correlation coefficients (ICCs) for intra- and interobserver reliability. METHODS: On the basis of HIZ criteria, a series of quantitative dimension and signal intensity measures was developed for assessing HIZ. Two experienced spine surgeons traced the region of interest twice within 4 weeks for assessment of the intra- and interobserver reliability. The quantitative variables were compared between groups A and B. RESULTS: There were 72 patients with LBP and 79 asymptomatic controls enrolling in this study. The prevalence of HIZ in group A and group B was 45.8% and 20.2%, respectively. The intraobserver agreement was excellent for the quantitative measures (ICC=0.838-0.977) as well as interobserver reliability (ICC=0.809-0.935). The mean signal of HIZ in group A was significantly brighter than in group B (57.55±14.04% vs. 45.61±7.22%, p=.000). There was no statistical difference of area of disc and HIZ between the two groups. The magnetic resonance imaging index was found to be higher in group A when compared with group B (3.94±1.71 vs. 3.06±1.50), but with a p value of .050. CONCLUSIONS: A series of quantitative measurements for HIZ was established and demonstrated excellent intra- and interobserver reliability. The signal intensity of HIZ was different in patients with or without LBP, and significant brighter signal was observed in symptomatic subjects.