Background Minimally invasive pedicle screw placement may have a higher incidence of violation of the superior cephalad unfused facet joint. Study Aims We investigated the incidence and risk factors of upper facet joint violation in percutaneous robot-assisted instrumentation versus percutaneous fluoroscopy-guided and open transpedicular instrumentation. Methods A retrospective study including all consecutive patients who underwent lumbar instrumentation, fusion, and decompression for spondylolisthetic stenosis and degenerative disk disease was conducted between January 2012 and January 2016. All operations were performed by the same surgeon; the patients were divided into three groups according to the method of instrumentation. Group 1 involved the robot-assisted instrumentation in 58 patients, group 2 consisted of 64 patients treated with a percutaneous transpedicular instrumentation using fluoroscopic guidance, and 72 patients in group 3 received an open midline approach for pedicle screw insertion. Results Superior segment facet joint violation occurred in 2 patients in the robot-assisted group 1 (7%), in 22 of the percutaneous fluoroscopy-guided group 2 (34%), and in 6 cases of the open group (8%). The incidence of facet joint violation was present in 5% (3) of the screws in group 1, 22% (28) of the screws in group 2, and 3% (4) of the screws in group 3. Conclusion Meticulous surgical planning of the appropriate entry site (Weinstein's method), trajectory planning, and proper robot-assisted instrumentation of pedicle screws reduced the risk of superior segment facet joint violation.

Objectives Tumour recurrence of glioblastoma multiforme (GBM) after initial treatment with surgical resection, radiotherapy and chemotherapy is an inevitable phenomenon. This retrospective cohort study compared the efficacy of interstitial high dose rate brachytherapy (HDR-BRT), re-resection and sole dose dense temozolomide chemotherapy (ddTMZ) in the treatment of recurrent glioblastoma after initial surgery and radiochemotherapy. Design Retropective cohort study. Setting Primary level of care with two participating centres. The geographical location was central Germany. Participants From January 2005 to December 2010, a total of 111 patients developed recurrent GBM after initial surgery and radiotherapy with concomitant temozolomide. The inclusion criteria were as follows: (1) histology-proven diagnosis of primary GBM (WHO grade 4), (2) primary treatment with resection and radiochemotherapy, and (3) tumour recurrence/progression. Interventions This study compared retrospectively the efficacy of interstitial HDR-BRT, re-resection and ddTMZ alone in the treatment of recurrent glioblastoma. Primary and secondary outcome measures Median survival, progression free survival and complication rate. Results Median survival after salvage therapy of the recurrence was 37, 30 and 26 weeks, respectively. The HDR-BRT group did significantly better than both the reoperation (p<0.05) and the ddTMZ groups (p<0.05). Moderate to severe complications in the HDR-BRT, reoperation and sole chemotherapy groups occurred in 5/50 (10%), 4/36 (11%) and 9/25 (36%) cases, respectively. Conclusions CT-guided interstitial HDR-BRT attained higher survival benefits in the management of recurrent glioblastoma after initial surgery and radiotherapy with concurrent temozolomide in comparison with the other treatment modalities. The low risk of complications of the HDR-BRT and the fact that it can be delivered percutaneously in local anaesthesia render it a promissing treatment option for selected patients which should be further evaluated.

Several studies have revealed that different salvage treatments in glioblastoma multiforme patients presenting a recurrence have limited palliative treatment options. The aim of this study was to evaluate the utility and limitations of multimodal salvage treatments in recurrent glioblastoma multiforme patients combining 5-aminolevulinic acid (5-ALA) fluorescence-guided resurgery, interstitial irradiation, and dense dose temozolomide chemotherapy (ddTMZ). Seventeen consecutive patients with recurrent globlastoma multiforme underwent a combined scheme of salvage treatments including fluorescence-guided reoperation, high dose rate (HDR) brachytherapy, and ddTMZ chemotherapy and were included in this prospective study. This multimodal treatment group was compared with a 1∶1 matched historical control group of 17 patients who have been treated with intensive temozolomide chemotherapy as the only treatment modality. All patients were previously treated with surgery of the primary pathology, concomitant, and adjuvant radiochemotherapy with temozolomide. Median follow-up was 32 months (range: 28-36 months). Median survival was 9 months for the entire cohort after salvage treatment and can be translated into a 3-month improvement in survival compared to the control group of patients with glioblastoma recurrence treated with temozolomide alone (P = 0·043). Complications rates of multimodal salvage treatment were comparable with the temozolomide control group. Our experience suggests that a combined salvage treatment plan have the advantages of all three methods and, thus, provide additional survival benefit and can be considered in selected patients affected by recurrent high grade gliomas. Nonetheless, more cases and additional studies are necessary to further prove the advantages of this multimodal treatment.