[Functional disorders and functional diseases in the region of the upper cervical spine particularly regarding the cervical joints. Current status and clinical relevance]

[Atlas block and alar ligament lesion-Underestimated or overrated?]

BACKGROUND

Disorders of the upper cervical spine, most notably lesions of the alar ligament and atlas block, are associated with numerous symptoms, especially as reported in the lay press. Thus, physicians are often confronted with patients who see in them a monocausal origin of complex complaints and hope for a quick remedy.

OBJECTIVE

This review article presents the currently available evidence-based literature on atlas block and alar ligament lesions in order to adequately appreciate their significance.

MATERIAL AND METHODS

Summary and critical evaluation of an extensive review of the literature on the diagnostics, clinical presentation, and treatment of disorders of the upper cervical spine.

RESULTS

The current literature shows that alar ligament lesions are caused only by extremely high-speed trauma and that the reliability of their detection on magnetic resonance imaging (MRI) is moderate at best. As several studies have failed to demonstrate a correlation between symptoms and abnormalities of the alar ligaments on MRI, surgical stabilization of the upper cervical joints is not indicated. The diversity of symptoms associated with atlas block may be explained by the convergence of afferent neurons originating in C1-C3 on several cranial nerve nuclei found in neuroanatomical studies, but this association has yet to be proven. First studies show that highly significant improvements in cervical pain and range of motion can be achieved by means of manual therapy of the upper cervical spine with lasting effects even after 6 months.

CONCLUSION

The importance of alar ligament lesions has often been overrated in the past; however, a more nuanced multifactorial understanding of the disorder should be conveyed to the patient. An atlas block should be considered mainly as a possible cause of pain and restricted range of motion of the cervical spine and in this context manual therapy can be an effective treatment option.

Congenital deformation of the posterior arch of the atlas: Subluxation of the atlanto-axial joint with temporary quadriplegia

Instabilities of the craniocervical junction can be of rheumatic, traumatic, or congenital origin. The reported patient has a congenital malformation of the cervical spine, which is frequently observed in patients with Klippel–Feil syndrome. Her posterior arch of the atlas (C1) is hypoplastic and a chronic subluxation of the atlanto-axial joint would be possible. Although most common fusions in Klippel–Feil syndrome patients exist at C2/3, the majority of studies about Klippel–Feil syndrome deal with pediatric or adolescent individuals. Through extreme flexion of her neck, there was a compression of the spinal cord by the odontoid process. This led to a quadriplegia lasting about 10 min. Over the following weeks, all of her symptoms started to diminish. This situation turned out to be the third episode involving temporary neurological disorders in this 60-year-old female’s life.

C1 fracture in a patient with a congenital cleft in the posterior arch: report on a failed conservative treatment

Unstable burst fractures of the atlas require sufficient immobilisation either with an external device or by surgical fusion. In patients with pre-existing congenital atlantal defects the decision whether to recommend non-operative or operative therapy is difficult. Treatment options are controversially discussed and standardised guidelines are not available. Although most surgeons advise operative fusion or osteosynthesis in atlanto-axial instability, non-operative immobilisation can be successful. We report on a patient with an unstable C1 burst fracture with a congenital posterior cleft in the atlantal arch who was treated with cervical extension and halovest immobilisation. Although callus bridging was initially observed, 9 months after the injury there was no sufficient fracture consolidation and surgical fusion had to be advised. While non-operative treatment may work in patients without congenital defects of the C1 arch, such is not recommended in patients who present with this anomaly.