[Hypophosphatemic rickets with normoalkaliphosphatemia, ossification of the posterior longitudinal ligament and yellow ligament]

Cervical intervertebral disc calcification combined with ossification of posterior longitudinal ligament in an-11-year old girl: case report and review of literature

To present the clinical feature, radiographic characteristic, treatment and prognosis of an 11 years old girl with cervical intervertebral disc calcification combined with ossification of posterior longitudinal ligament(OPLL).

BACKGROUND

Calcification is the degeneration of intervertebral disc, mostly occurs in the cervical segment. The pediatric cervical intervertebral disc calcification associated with OPLL is very rare. The etiology and treatment guidelines of this complex are poorly known.

METHOD

An 11 years old girl experienced neck pain for 3 months,aggravated for half a month. Neurological examination revealed the limitation of cervical spine motion and numbness of the upper left extremity. The spine radiograph, computed tomography and magnetic resonance imaging confirmed the diagnosis of cervical intervertebral disc calcification accompanied with OPLL. Conservative intervention was performed, followed up with an observation for 6 months.

RESULT

On admission, the spine radiograph and computed tomography found the calcified intervertebral disc of C5/6 and ossified posterior longitudinal ligament at C5/6,C6 level, leading to spinal canal stenosis and spine cord compression. After a two-week in-hospital conservative treatment, the patient's neurologic symptoms were relieved. Two months later, the computed tomography confirmed the calcification of C5/6 intervertebral disc and ossified mass decreased significantly, spinal stenosis subsided. Six months later, the patient felt no discomfort, the computed tomography showed the ossified mass completely disappeared, only a small calcification remained at C5/6 intervertebral disc.

CONCLUSION

Intervertebral disc calcification associated with OPLL is extremely rare in children. In this case, OPLL is a temporary condition highly related to the disease process of Intervertebral disc calcification. The patient has a satisfactory recovery after non-surgical intervention. Conservative treatment is a prospective choice.

Ossification of the Posterior Longitudinal Ligament: Imaging Findings in the Era of Cross-Sectional Imaging

Imaging appearance and classification systems of ossification of the posterior longitudinal ligament (OPLL) on computed tomography and magnetic resonance imaging will be reviewed. Computed tomography evaluation most accurately demonstrates OPLL length and thickness, whereas magnetic resonance imaging has the advantage of demonstrating abnormal signal in the cord. Neurologic symptoms are most common in the cervical spine and are related to the degree of spinal stenosis and presence of cord edema. Surgical treatment usually involves cases of cervical OPLL and includes anterior or posterior decompression.

Analysis of demographics, risk factors, clinical presentation, and surgical treatment modalities for the ossified posterior longitudinal ligament

OBJECT

Ossification of the posterior longitudinal ligament (OPLL) is a rare disease that results in progressive myeloradiculopathy related to pathological ossification of the ligament from unknown causes. Although it has long been considered a disease of Asian origin, this disorder is increasingly being recognized in European and North American populations. Herein the authors present demographic, radiographic, and comorbidity data from white patients with diagnosed OPLL as well as the outcomes of surgically treated patients.

METHODS

Between 1999 and 2010, OPLL was diagnosed in 36 white patients at Barrow Neurological Institute. Patients were divided into 2 groups: a group of 33 patients with cervical OPLL and a group of 3 patients with thoracic or lumbar OPLL. Fifteen of these patients who had received operative treatment were analyzed separately. Imaging analysis focused on signal changes in the spinal cord, mass occupying ratio, signs of dural penetration, spinal levels involved, and subtype of OPLL. Surgical techniques included anterior cervical decompression and fusion with corpectomy, posterior laminectomy with fusion, posterior open-door laminoplasty, and anterior corpectomy combined with posterior laminectomy and fusion. Comorbidities, cigarette smoking, and previous spine surgeries were considered. Neurological function was assessed using a modified Japanese Orthopaedic Association Scale (mJOAS).

RESULTS

A high-intensity signal on T2-weighted MR imaging and a history of cervical spine surgery correlated with worse mJOAS scores. Furthermore, mJOAS scores decreased as the occupying rate of the OPLL mass in the spinal canal increased. On radiographic analysis, the proportion of signs of dural penetration correlated with the OPLL subtype. A high mass occupying ratio of the OPLL was directly associated with the presence of dural penetration and high-intensity signal. In the surgical group, the rate of neurological improvement associated with an anterior approach was 58% compared with 31% for a posterior laminectomy. No complications were associated with any of the 4 types of surgical procedures. In 3 cases, symptoms had worsened at the last follow-up, with only a single case of disease progression. Laminoplasty was the only technique associated with a worse clinical outcome. There were no statistical differences (p > 0.05) between the type of surgical procedure or radiographic presentation and postoperative outcome. There was also no difference between the choice of surgical procedure performed and the number of spinal levels involved with OPLL.

CONCLUSIONS

Ossification of the posterior longitudinal ligament can no longer be viewed as a disease of the Asian population exclusively. Since OPLL among white populations is being diagnosed more frequently, surgeons must be aware of the most appropriate surgical option. The outcomes of the various surgical treatments among the different populations with OPLL appear similar. Compared with other procedures, however, anterior decompression led to the best neurological outcomes.

Surgical treatment of multiple spinal canal stenoses associated with vitamin D-resistant rickets

We describe a 44-year-old woman who was diagnosed in childhood with vitamin D-resistant rickets, and who had paraparesis due to multiple spinal canal stenoses between C5 and L1 with ossification of the posterior longitudinal ligament and the yellow ligament. She was treated surgically with laminoplasty of the C2 through C7 levels and laminectomy from T8 through T11. Four months later, she underwent anterior fusion using an ilium graft by thoracotomy from the T12 to L1 levels. Six months after surgery, her symptoms improved. After 5 years, and with oral vitamin D, no progression of symptoms has been observed.

Ossification of the Posterior Longitudinal Ligament: An Update on Its Biology, Epidemiology, and Natural History

SIGNIFICANT PROGRESS HAS been achieved in basic research during the past decade on the pathogenesis of ossification of the posterior longitudinal ligament (OPLL), a multifactorial disease in which complex genetic and environmental factors interact. A review of the literature was conducted to update recent findings on the biology, epidemiology, natural history, and related diseases of OPLL. Gene analysis studies found specific polymorphisms that may be associated with OPLL in several collagen genes, which encode for extracellular matrix proteins. Polymorphisms in the nucleotide pyrophosphate gene, which is involved in regulation of calcification in chondrocytes, may also be associated with OPLL. However, the results of the gene analysis studies have not always been consistent. Involvement of many growth factors and cytokines, including bone morphogenic proteins and transforming growth factor-β, has been demonstrated in various histochemical and cytochemical analyses. Several transcription factors involved in cellular differentiation may also have a role. Recent epidemiological studies reaffirmed an earlier finding that diabetes mellitus is a distinct risk factor for OPLL. The long-term follow-up studies of OPLL patients are disclosing the natural history, as well as the frequency and rate of progression, of OPLL after surgical intervention. Further knowledge on the factors responsible for progression of OPLL may predict its behavior in each patient, and treatment may be tailored accordingly. The coexistence of OPLL with other diseases of ectopic ossification of the spine, such as ossification of the ligamentum flavum and diffuse idiopathic skeletal hyperostosis, is not uncommon. Scientific breakthrough in those diseases may, in turn, give insights into the pathogenesis of OPLL.