Case report: absent C6 cervical pedicle in a collegiate football player

Abstract

Congenital absence of a cervical pedicle is a rare clinical finding with only 70 reported cases in the literature from 1946 until present. The congenitally absent pedicle has clinical importance owing to the frequency of misdiagnosis and inappropriate invasive treatments. We present the case of a 21-year-old college football player who experienced neck and shoulder pain after violent twisting of his neck by the face mask. The player walked off the field under his own power. He was sent to the locker room, where he underwent right shoulder and cervical spine radiographs. Initial review of the radiographs raised concern for a jumped right C6 facet. The patient then underwent CT and MRI of the cervical spine, confirming the diagnosis of an absent cervical pedicle. He was treated nonoperatively for a short time and completed the season. He had no symptoms at last followup at 8 months. The most frequent location of the absent cervical pedicle is at the C6 level, and the next most common is at the C5 level. Neural compression or instability is uncommon and nonsurgical treatment is the mainstay of treatment. Misdiagnosis can lead to inappropriate treatment such as halo or tong application with traction, which occurred in seven of 57 cases in one series, and exploratory surgery, which occurred in four of 57 cases.

Fig. 1

An axial cut from the CT of the cervical spine reveals the absent C6 pedicle on the right.

Fig. 2

A CT sagittal image reveals the large space where the pedicle normally sits.

Fig. 3

A coronal view at the level of C6 shows the obviously absent right C6 pedicle.

Fig. 4

A three-dimensional reconstruction of the CT again shows the absent C6 pedicle on the right.

Fig. 5

A T2-weighted MR image shows no canal narrowing or neurologic compromise at the C6 level.