Posterior displacement associated with dens fracture nonunions in elderly patients

Researchers also found lack of surgical management was a factor that can lead to nonunion of odontoid fractures.

A retrospective study showed there are several factors associated with nonunion in older patients with odontoid fractures, which are the most common cervical spine injuries in the elderly population and have high rates of morbidity and mortality associated with them, the researchers said.

“Factors associated with nonunion included type 2 odontoids, as expected, posterior more than anterior translated fractures, nonoperative management, males more than females, and low energy versus high energy mechanisms, congestive heart failure and increased comorbidities (Charlson score),” Clifford B. Jones, MD, said when he presented the results.

For the study, Jones and colleagues identified the fractures by the Anderson and D’Alonzo classification and their evaluation focused on translation, angulation and displacement measurements.

Radiographic evaluations

“We evaluated the fusion or union of the fracture based on flexion/extension radiographs, no motion between the C1-2, CT scan with bridging bone across the site, or both,” Jones said.

This radiograph demonstrates posterior
displaced type 2 odontoid nonunion in a
man who is 82 years old and has multiple
comorbidities.

Image: Jones CB

Among 97 consecutive patients with type 2 or 3 odontoid fractures with an average age of 80 years, 20 patients died before 6-months follow-up and 73 patients were treated at a single Level 1 trauma center between 2002 and 2011 and participated in the final study. The mechanism of injury was low energy in 66 (68%) cases, he said.

The patients were followed in a single large private practice, and retrospectively evaluated.

The final group of patients evaluated consisted of 31 men and 42 women who had an overall fusion rate of 71.2%, based on the results. Some of the patients initially received nonoperative care and others were primarily treated with surgery.

Five main factors

Jones and colleagues found there were several factors that were closely associated with odontoid fracture nonunions in these patients.

“There are five factors associated with nonunion. Type 2 had a higher rate of nonunion than type 3, as is to be expected. Posterior displaced fractures have a higher rate of nonunion than translated or anterior displaced. Surgical management had a higher rate of union than collar immobilization. Females had a higher rate of union than males, and higher energy mechanisms of injury in older patients had a higher level of union,” Jones said.

Patients treated with nonsurgical management showed a lower rate of fusion, 60.8%, than the group that underwent surgery to fix their fractures, which had a 95.5% fusion rate. Men had a 58.1% rate of fusion compared with women, whose overall fusion rate was 81%, according to the results.

Additionally, Jones and colleagues reported type 2 fractures were associated with a union rate of 67% and type 3 fractures were associated with an 83% fusion rate.

There were several factors the researchers found that did not have a statistical significance in regard to union. These included age, body mass index, tobacco use, sagittal fracture displacement, direction of displacement, type of odontoid fracture, odontoid angle, time to surgery, method of nonsurgical management, time to discontinuation of a rigid collar and surgical technique, Jones and colleagues noted in the study. – by Robert Linnehan

Reference:

Jones CB. Paper #74. Presented at: Orthopaedic Trauma Association Annual Meeting; Oct. 9-12, 2013; Phoenix.

For more information:

Clifford B. Jones, MD, can be reached at Orthopaedic Associates of Michigan, 230 Michigan NE, Suite 300, Grand Rapids, MI 49503; email: clifford.jones@oamichigan.com.
Disclosure: Jones has no relevant financial disclosures.