Methods: 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. Results: 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. Conclusions 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.

OBJECTIVE: The diagnosis of insufficiency fractures of the sacrum in an elder population increases annually. Fractures show very different morphology. We aimed to classify sacral insufficiency fractures according to the position of cortical break and possible need for intervention.METHODS: Between January 1, 2008 and December 31, 2014, all patients with a proven fracture of the sacrum following a low-energy or an even unnoticed trauma were prospectively registered : 117 females and 13 males. All patients had a computer tomography of the pelvic ring, two patients had a magnetic resonance imaging additionally : localization and involvement of the fracture lines into the sacroiliac joint, neural foramina or the spinal canal were identified.RESULTS: Patients were aged between 46 and 98 years (mean, 79.8 years). Seventy-seven patients had an unilateral fracture of the sacral ala, 41 bilateral ala fractures and 12 patients showed a fracture of the sacral corpus : a total of 171 fractures were analyzed. The first group A included fractures of the sacral ala which were assessed to have no or less mechanical importance (n=53) : fractures with no cortical disruption (“bone bruise”) (A1; n=2), cortical deformation of the anterior cortical bone (A2; n=4), and fracture of the anterolateral rim of ala (A3; n=47). Complete fractures of the sacral ala (B; n=106) : parallel to the sacroiliac joint (B1; n=63), into the sacroiliac joint (B2; n=19), and involvement of the sacral foramina respectively the spinal canal (B3; n=24). Central fractures involving the sacral corpus (C; n=12) : fracture limited to the corpus or finishing into one ala (C1; n=3), unidirectional including the neural foramina or the spinal canal or both (C2; n=2), and horizontal fractures of the corpus with bilateral sagittal completion (C3; n=8). Sixty-eight fractures proceeded into the sacroiliac joint, 34 fractures showed an injury of foramina or canal.CONCLUSION: The new classification allowes the differentiation of fractures of less mechanical importance and a risk assessment for possible polymethyl methacrylate leaks during sacroplasty in the direction of the neurological structures. In addition, identification of instable fractures in need for laminectomy and surgical stabilization is possible.
Cementoplasty ; Classification ; Diagnosis ; Female ; Fractures, Stress ; Humans ; Laminectomy ; Magnetic Resonance Imaging ; Male ; Polymethyl Methacrylate ; Prospective Studies ; Risk Assessment ; Sacroiliac Joint ; Sacrum ; Spinal Canal