Spinal Epidural Venous Plexus Pathology in Hirayama Disease

Correlation Study Between Spinal Cord Function, Spinal Cord Morphology and Cervical Spine Alignments in Patients With Hirayama Disease

OBJECTIVE

This study aimed to explore the relationship between diffusion tensor imaging (DTI) parameters, cervical spine alignments, and spinal cord morphological parameters in patients with Hirayama disease (HD).

METHODS

In this retrospective cohort study, 41 HD patients were recruited from the Huashan hospital from July 2017 to November 2021. Patients received X-rays, conventional magnetic resonance (MR), and DTI scans in flexion and neutral positions. The DTI parameters assessed were calculated using the region of interest (ROI) method. Paired t-tests were performed on the DTI parameters of neck flexion and neutral position. Cervical spine alignments, including flexion and neutral Cobb angles, were measured, and range of motion (ROM) was calculated. Spinal cord morphological parameters were measured, including spinal cord atrophy (SCA) and loss of attachment (LOA). Spearman's correlation analysis between DTI parameters, cervical spine alignments, and spinal cord morphological parameters was performed.

RESULTS

In comparing DTI parameters, segments of the C3/4, C4/5, C6/7, and lower cervical spine were significantly different, while segments of C5/6 were not significantly different. In Spearman's correlation analysis, the flexion Cobb angle was significantly correlated with the fractional anisotropy (FA) value (R2 = .111, P = .033) and apparent diffusion coefficient (ADC) value (R2 = .119, P = .027). Flexion FA values were correlated with SCA in C4/5 (R2 = .211, P = .003), C5/6 (R2 = .454, P < .001), and C6/7 (R2 = .383, P < .001) while flexion ADC values were correlated with SCA in the C4/5 (R2 = .178, P = .006), C5/6 (R2 = .388, P < .001) and C6/7 segments (R2 = .187, P = .005).

CONCLUSION

The DTI parameters were correlated with the flexion Cobb angle and the SCA. These data support the dynamic cervical flexion compression hypothesis and indicate that the degree of SCA may be used to assess the condition of HD patients quantitatively.

Do patients with Hirayama disease require surgical treatment? A review of the literature

The main clinic characteristic of Hirayama disease (HD) is atrophy of the distal muscles in the upper limbs. Recently, an increasing number of HD cases have been reported. Many HD patients have persistently progressive symptoms and conservative treatments failed. This article aims to review the current status of the field and summarizes the main surgical treatment options for patients with HD. A comprehensive search of the PubMed and the Web of Science databases was conducted from their inception to September 15th, 2022. Search terms included "juvenile muscular atrophy of upper extremity", "Hirayama disease" and "surgery". A total of 169 relevant publications were identified and 29 articles were finally reviewed. Current surgical treatments for HD are either anterior cervical surgery or posterior cervical surgery. The two approaches can effectively stop the disease. However, no studies have compared the advantages and limitations of the two surgical methods. The previous view that HD can be improved with conservative treatment has been challenged. In many studies, surgical treatment has been shown to improve the hand function in patients with HD. However, there is still controversy about the methods of anterior and posterior cervical surgery. Future research could focus on exploring the advantages and limitations of different surgeries.

Rare cause of unilateral upper limb weakness in a young adolescent

Slowly progressing unilateral upper limb weakness in a previously healthy child can occur due to number of causes which requires a thorough history, physical examination followed by radiological examination, electromyography and so on. Among the various aetiologies, a rare condition such as Hirayama disease is one of the differentials to be considered. There has been a wealth of literature reported on this disease and our case is a learning lesson for all paediatricians to be aware of Hirayama disease and its current concepts.