Decompression for botulinum toxin-exacerbated cervical myeloradiculopathy in the setting of congenital stenosis and Arnold–Chiari I malformation

Abstract

This case reports a severe and nonspecific presentation of cervical myeloradiculopathy. Surgery for cervical myeloradiculopathy is controversial, and conservative therapy is initially preferred. However, in this case, conservative treatments likely led to paraspinal weakness, cervical hypermobility, and biomechanical instability, resulting in exacerbation of symptoms. Stretch/shear forces have been postulated to accelerate cervical myelopathy, and excessive cervical instability and range of motion are significant predictors of deterioration. In this case, surgical decompression with posterior cervical laminoplasty after 1 year of conservative management yielded significant pain relief and functional restoration, indicating the utility of this procedure even in the presence of Arnold-Chiari I malformation. This case illustrates that decompression can be effective for refractory cervical myeloradiculopathy associated with Chiari malformation, congenital stenosis, and prior anterior instrumentation, and highlights the potential risks of prolonged conservative management.

Botulinum Toxin Injections as a Treatment of Postoperative Chronic Neck Pain Secondary to Cervical Spine Surgery

“…11,13 Chronic administration can lead to muscle denervation and weakness, which can lead to more severe issues, such as "scooped out" shoulder, 3 a narrowed neck, and dropped-head syndrome. 4,5,16 Chronic usage can also lead to anti-BTX antibody formation, which blocks the action of BTX in the body. Proper monitoring of patients' responses to BTX and not administering it more often than every 12 weeks are the keys to avoiding these adverse effects.…”

“…15 Chronic BTX usage can additionally cause a phenomenon known as dropped-head syndrome, a disabling condition caused by extreme weakness of the neck extensor musculature, leading to progressive cervical kyphosis and the inability to lift the head up against gravity. 4,5,16 This complication can occur when BTX injections are applied to the muscles of neck extension. Hogan et al described a patient who had previously underwent C3 to C5 decompression and fusion, with rapidly progressing cervical kyphosis and severe neck weakness after receiving BTX-A "trigger point" injections into her neck extensor muscles for associated neck pain.…”

“…With her avoidance of physical therapy, the authors postulated that her dropped-head syndrome was caused by biomechanical paraspinal instability and cervical hypermobility secondary to long-term BTX usage. 4 At high doses, use of perioperative BTX can increase the risk of postoperative complications due to respiratory and swallowing difficulties, such as pneumonia. This results from neuromuscular blockade of muscles that are essential for normal respiration and swallowing.…”

“…3 With the added stability of the neck due to vertebral fusion hardware, are BTX injections a possible treatment? BTX injections have previously been applied in the head and neck region for chronic pain relief in conditions such as blepharospasm, trigeminal neuralgia, facial pain, cervicogenic headaches, cervical dystonia, chronic neck pain, temporomandibular disorders, and migraines, [3][4][5] but they have not been frequently utilized in regard to postoperative chronic neck pain. The purpose of this systematic review of the current literature is to summarize all of the pertinent studies that have been published regarding BTX injections as a treatment option for postoperative chronic neck pain secondary to cervical spine surgery.…”

The Effect of Low Dose OnabotulinumtoxinA on Cervical Dystonia in Hypermobile Ehlers-Danlos Syndrome

“…Cervical dystonia is particularly problematic and difficult to treat in the hypermobile population and can exacerbate myeloradiculopathy or atlantoaxial subluxation [ 8 9 ]. A significantly smaller dose of botulinum toxins may be warranted and sufficient in this patient population to avoid destabilization [ 10 ].…”