[Spontaneous resorption of thoracic calcified disc herniation: Report of two cases and review of the literature]

Emerging Issues Questioning the Current Treatment Strategies for Lumbar Disc Herniation

Lumbar disc herniation is among the common phenotypes of degenerative lumbar spine diseases, significantly affecting patients' quality of life. The practice pattern is diverse. Choosing conservative measures or surgical treatments is still controversial in some areas. For those who have failed conservative treatment, surgery with or without instrumentation is recommended, causing significant expenditures and frustrating complications, that should not be ignored. In the article, we performed a literature review and summarized the evidence by subheadings to unravel the cons of surgical intervention for lumbar disc herniation. There are tetrad critical issues about surgical treatment of lumbar disc herniation, i.e., favorable natural history, insufficient evidence in a recommendation of fusion surgery for patients, metallosis, and implant removal. Firstly, accumulating evidence reveals immune privilege and auto-immunity hallmarks of human lumbar discs within the closed niche. Progenitor cells within human discs further expand the capacity with the endogenous repair. Clinical watchful follow-up studies with repeated diagnostic imaging reveal spontaneous resolution for lumbar disc herniation, even calcified tissues. Secondly, emerging evidence indicates long-term complications of lumbar fusion, such as adjacent segment disease, pseudarthrosis, implant failure, and sagittal spinal imbalance, which get increasing attention. Thirdly, systemic and local reactions (metallosis) for metal instrumentation have been noted with long-term health concerns and toxicity. Fourthly, the indications and timing for spinal implant removal have not reached a consensus. Other challenging issues include postoperative lumbar stiffness. The review provided evidence from a negative perspective for surgeons and patients who attempt to choose surgical treatment. Collectively, the emerging underlying evidence questions the benefits of traditional surgery for patients with lumbar disc herniation. Therefore, the long-term effects of surgery should be closely observed. Surgical decisions should be made prudently for each patient.

Spontaneous regression and near disappearance of a calcified herniated thoracic disc in a 44-year-old male: illustrative case

BACKGROUND

Herniation of an intervertebral disc (IVD) is found predominantly in the lumbar and cervical spine of both children and adults, but herniated IVDs of the thoracic spine are a rare occurrence. However, approximately 40% of herniated thoracic disc cases are calcified. Approximately 0.65% of all spinal herniations are calcified herniated thoracic discs (CHTDs). CHTDs can be treated conservatively or invasively, depending on the symptoms and degree of neurological deficit present.

OBSERVATIONS

The authors report a 44-year-old male with near complete reabsorption and disappearance of a CHTD. A review of the available literature indicates that there are only seven adult patients in whom this phenomenon has been reported.

LESSONS

Determining the best form of invasive treatment is a challenge for surgeons given the complexity of this condition. While the disappearance of calcified herniated discs of the lumbar and cervical spine has been reported, reports of the regression of CHTDs are rare. The disappearance of CHTDs is more commonly reported in children who undergo conservative treatment, while surgery is reserved for children who experience progressive pain and neurological deficit. Given the success of conservative treatment of CHTDs in children, conservative treatment methods should be considered when treating mildly symptomatic adults.

Acute Calcific Discitis or Symptomatic Calcified Schmorl's Node of the Upper Thoracic Spine in an Adult: A Case Report and Literature Review

We describe a patient with acute calcific discitis following symptomatic Schmorl's node (SN) of upper thoracic spine. A 28-year-old female suffered from sudden severe pain in mid-thoracic, left scapular area, radiating to her chest. Plain radiography of the thoracic spine showed calcification in T3–4 intervertebral disc space. Computed tomography (CT) scan and magnetic resonance imaging (MRI) of the spine demonstrated calcification of the T3–T4 nucleus pulposus, migrating into the inferior of T3 vertebral body with reactive bone marrow edema. By conservative treatment with multidrug therapy, the pain subsided and disappeared in 3 months. Follow-up CT scan and MRI of the thoracic spine confirmed complete resolution of calcified SN and reactive bone marrow edema.

Regression of a symptomatic thoracic disc herniation with a calcified intervertebral disc component

There were only a few cases describing spontaneous regression of calcified thoracic disc herniation in the literature. We present a 38-year-old male office worker who had left paramedian-foraminal extruded disc at T7-T8 with calcifications of the T7-T8 and T8-T9 intervertebral discs. This case was unique in that the non-calcified extruded disc material regressed almost completely in 5 months while the calcified intervertebral discs remained the same during the process of regression. This report stresses that regression of the herniated material of the thoracic discs with subsidence of the symptoms is still possible even if the disc material is calcified.

Calcific discitis with giant thoracic disc herniations in adults

PURPOSE

Calcific discitis is a self-limiting process most commonly seen in the cervical spine of children. Rare literature exists regarding the natural history and management of this condition in adults, especially when it presents as a giant thoracic disc herniation into the spinal canal. Giant herniations in the thoracic spine are typically surgically removed to reduce the chance of permanent neurologic deficit from spinal cord compression. However, when associated with calcific discitis, they may undergo spontaneous regression with the need for surgery obviated.

METHODS

Medical records and radiographic studies of two adult patients with calcific discitis and myelopathy due to spinal cord compression by giant thoracic disc herniations were retrospectively reviewed. Search of the literature on calcific discitis in adults and spontaneous regression of calcified thoracic disc herniations was separately performed.

RESULTS

Both patients were young male adults presenting with back pain and early signs of myelopathy. With restriction of activities and oral NSAIDs, their symptoms were relieved within 3 months. Four adult cases of calcific discitis (characteristic central calcification confined within the nucleus pulposus) and three instances of spontaneous regression of small- to medium-sized thoracic calcified disc herniations were identified from the literature.

CONCLUSIONS

The demonstration of spontaneous resorption of giant calcified thoracic disc herniations in two adult patients with calcific discitis supplements the existing literature and provides the first evidence that giant calcified thoracic disc herniations may still undergo spontaneous remission and a "wait and watch" strategy may be justified at least in the initial management of these patients, even with the presence of mild myelopathy.