Charcot Spinal Arthropathy (CSA) also known as Spinal Neuroarthropathy is a very rare, progressive degenerative disorder of the vertebral joints. It develops due to reduced afferent innervation. Originally, this pathology was described as a consequence of tabes dorsalis (tertiary stage of syphilis). Today, CSA most commonly occurs after spinal cord injuries. Proprioceptive and nociceptive disturbances lead to reduced muscle contractions, resulting in microtrauma and progressive degeneration of cartilage and intervertebral discs. The thoracolumbar vertebral bodies are most affected, with possible fractures, joint instability, deformities, subluxations, and dislocations. Neurological dysfunctions and pain are consequences of this disease.

Epidemiology

Up to 70% of spinal Charcot arthropathy cases develop following spinal injury. Less common causes are listed below. The estimated prevalence of CSA after spinal injury is about 1 in 220. The incidence in the USA is 54 per 1 million. The disease most frequently occurs in the fifth decade of life, with men being more commonly affected (likely due to the higher frequency of spinal cord injuries from trauma).

Other risc factors and predispositions

Clinical presentation

Symptoms in patients with CSA are non-specific. The most common symptoms include back pain, spinal instability especially when sitting, spinal deformities (typically kyphosis), and audible noises such as cracking or crunching of the spine during movement. Back pain may also result from accompanying autonomic dysreflexia proximal to the lesion.

Radiological findings

CT imaging may show large osteophytes and bone fragment debris caused by juxta-articular bone destruction and parallel new bone formation. Gas inclusions in the intervertebral space are common and due to increased segmental mobility. Degeneration of the facet joints occurs concurrently. Anterolisthesis or retrolisthesis are also typical radiological features. MRI shows active remodeling structures with possible significant enhancement, T2 hyperintensity, and possibly bone marrow or facet joint edema with destruction.

Differential diagnoses

• Metastases (osseous, osteoblastic)
• Infections (spondylodiscitis)

Indication for surgery

Due to the rarity of the disease, there are no high-evidence studies. Guidelines are derived from case reports and systematic reviews. The goal of treatment during the active disease process is immobilization of the affected joints to prevent fractures and progression of deformities.
Conservative management with orthoses is mentioned in the literature but plays a minor role. For elderly, non-operable patients, orthoses are the only option. Young patients with minimal pain or only mild neurological deficits can be managed with immobilization in the early phase, but regular follow-up is necessary to detect progression early.
Surgical treatment in the form of spondylodesis over the affected segments is now considered the therapy of choice. A posterior-only fusion (e.g., minimally invasive management) is possible. However, a 360° fusion (vertebral body replacement & posterior fusion) with debridement of destroyed vertebral bodies, joints, and disc structures is recommended.
The additional use of bone morphogenetic protein (BMP) increases the fusion rate, especially in 360° fusions. The additional administration of bisphosphonates is discussed in the literature.

Outcome

There are no long-term data to make precise statements about outcomes after surgical treatment of Charcot spinal arthropathy. Failure of spondylodesis and subsequent revision after posterior-only fusion is estimated at about 50–60%. With 360° fusion, about 30% require revision surgery. Due to the complexity of this disease, an individual strategy should be developed for each patient, considering the severity of symptoms, functional impairments, the patient’s functional capacity, and how surgical treatment will affect postoperative autonomy.

References

• Ivan Urits , Ariunzaya Amgalan, Jacob Israel, et al. A comprehensive review of the treatment and management of Charcot spine, Ther Adv Musculoskel Dis 2020, Vol. 12: 1–11
• Dennis Lee, Nader S Dahdaleh, Charcot spinal arthropathy, J Craniovertebr Junction Spine. 2018 9(1): 9-19
• Moreau S, Lonjon G, Jameson R, et al. Do all Charcot spine require surgery? Orthop Traumatol Surg Res 2014; 100:779–784.
• Lee Y-P, Farhan SA, Kiester PD, et al. Charcot disease of the spine. Contemp Spine Surg 2020; 21: 1–5.
• Morita M, Miyauchi A, Okuda S, et al. Charcot spinal disease after spinal cord injury: clinical article. J Neurosurg Spine 2008; 9: 419–426
• Jacobs WB, Bransford RJ, Bellabarba C, et al. Surgical management of Charcot spinal arthropathy: a single-center retrospective series highlighting the evolution of management. J Neurosurg Spine 2012; 17: 422–431
• Gupta R. A short history of neuropathic arthropathy. Clin Orthop Relat Res 1993; 49: 43–49.
• Lee D and Dahdaleh NS. Charcot spinal arthropathy. J Craniovertebral Junction Spine 2018; 9: 9–19.