Midterm outcome after posterior stabilization of unstable Midthoracic spine fractures in the elderly

Abstract

Background: The evidence for the treatment of midthoracic fractures in elderly patients is weak. The aim of this study was to evaluate midterm results after posterior stabilization of unstable midthoracic fractures in the elderly.

Methods: Retrospectively, all patients aged ≥65 suffering from an acute unstable midthoracic fracture treated with posterior stabilization were included. Trauma mechanism, ASA score, concomitant injuries, ODI score and radiographic loss of reduction were evaluated. Posterior stabilization strategy was divided into short-segmental stabilization and long-segmental stabilization.

Results: Fifty-nine patients (76.9 ± 6.3 years; 51% female) were included. The fracture was caused by a low-energy trauma mechanism in 22 patients (35.6%). Twenty-one patients died during the follow-up period (35.6%). Remaining patients (n = 38) were followed up after a mean of 60 months. Patients who died were significantly older (p = 0.01) and had significantly higher ASA scores (p = 0.02). Adjacent thoracic cage fractures had no effect on mortality or outcome scores. A total of 12 sequential vertebral fractures occurred (35.3%). The mean ODI at the latest follow up was 31.3 ± 24.7, the mean regional sagittal loss of reduction was 5.1° (± 4.0). Patients treated with long segmental stabilization had a significantly lower rate of sequential vertebral fractures during follow-up (p = 0.03).

Conclusion: Unstable fractures of the midthoracic spine are associated with high rates of thoracic cage injuries. The mortality rate was rather high. The majority of the survivors had minimal to moderate disabilities. Thereby, patients treated with long segmental stabilization had a significantly lower rate of sequential vertebral body fractures during follow-up.

Keywords: Long segmental posterior stabilization; Midthoracic spine; Osteoporotic vertebral body fracture; Posterior stabilization; Thoracic cage injury.

Fig. 1

Depicted is the definition of the relative medial vertebral body height: (AB / $\frac{\mathit{CD}+\mathit{EF}}{2}$)*100 in percent. Thereby the height is measured at midpoint of the vertebral body in the sagittal view

Fig. 2

Seventy-eight-year female patient, who stumbled and fell down the stairs. A burst fracture of 3rd thoracic vertebral body with injury of the posterior column (OF 5) and an incomplete burst fracture of the 4th thoracic vertebral body was detected (a-d). Open posterior long-segmental stabilization was performed 3 days after the accident (e, f). At the latest follow-up after 26 months, the patient had only low pain levels without any pain medication (VAS: 2). No radiologic loss of reduction and compensated sagittal spinal alignment was visible (g, h)

Fig. 3

Sixty-eight-year female patient who suffered an acute incomplete burst fracture type OF 3 of the 8th thoracic vertebral body after falling while clearing snow. Surgery was indicated as result of the persistent immobilizing pain and the radiologic loss of reduction leading to a bisegmental kyphosis of 26° (a, b). A short segmental stabilization including cement augmentation of the fractured vertebral body was performed 7 days after the accident (c, d). At the further course an atraumatic subsequent fracture of the 3rd lumbar vertebral body occurred. At the latest follow-up after 69 months, the patient complained of permanent relevant pain (VAS: 6), moderate limitations (ODI: 45), and mild reduction loss as well as consolidated fracture 3rd lumbar body (e, f)

Fig. 4

Box plot comparing the ODI scores between patients treated with short segmental stabilization (SSS) and long segmental stabilization (LSS) at the final follow-up examination after a mean of 5 years

Fig. 5

Box plot comparing the radiological bisegmental loss of reduction scores between patients treated with short segmental stabilization (SSS) and long segmental stabilization (LSS) at the final follow-up examination after a mean of 5 years