Thoracoscopic Correction of Post-traumatic Kyphosis with an Expandable Cage: Radiologic and Patient-Reported Outcomes

Retrospective cohort study.

To determine the long-term functional and radiological outcomes after thoracoscopic post-traumatic kyphosis (PTK) correction (PTKC).

PTK after insufficient treatment of unstable fractures usually presents with pain and decreased back function. The results of PTKC using a minimally invasive thoracoscopic approach with an anterior titanium cage have not previously been reported.

Data in this study were collected from all patients who underwent thoracoscopic PTKC with an expandable cage between 2007 and 2017. Kyphosis and intervertebral body height were assessed on radiographic material. Quality of life (QOL) and functional outcome scores were determined by the Euroquol 5 dimensions (EQ5D) and the Oswestry Disability Index (ODI). Additionally, satisfaction and subjective symptom improvement were determined.

Fourteen patients were treated for symptomatic PTK using a combined thoracoscopic anterior and posterior approach. Nine patients received initial conservative fracture treatment and five patients underwent initial posterior fracture fixation. All patients presented with pain and without neurologic injury. The mean time between injury and PTKC was 15.4 months. Cobb angle (CA) improved with 10.6° immediately after PTKC. During the first follow-up, 4.8° kyphosis correction was lost, but CAs remained stable at longer follow-up. Bony fusion was achieved in 92% of the patients after 16 months. The majority of patients reported an improvement of symptoms 85 months after surgery, satisfaction with and willingness to undergo the procedure again. The mean EQ5D index score was 0.71 and the mean ODI score was 22.3.

The results of minimally invasive thoracoscopic PTKC using an expandable cage were satisfactory. The majority of the patients were satisfied after treatment and no neurological complications occurred. Functional and QOL scores were fairly good. Whereas some postoperative kyphosis correction was lost over time, bony fusion was achieved in the majority of the patients. The thoracoscopic approach minimizes surgical morbidity, does not lead to serious complications, and provides a good option for PTKC.