Percutaneous Cementation for Improvement of Pain and Function for Osteolytic Pelvic Metastasis: A Systematic Review.

INTRODUCTION: Pelvic metastasis is a common presentation among patients presenting with skeletal metastasis. Image-guided percutaneous cementation of these lesions is becoming increasingly popular for the treatment of these lesions. The objective of this study was to conduct a systematic review that investigates clinical outcomes after percutaneous cementation for pelvic metastasis. METHODS: A systematic review was registered with International Prospective Register of Systematic Reviews and performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using the PubMed, SCOPUS, and Ovid MEDLINE databases. All level I to IV clinical studies published in the English language investigating the clinical outcomes after percutaneous cementation for pelvic metastasis were included. RESULTS: Fourteen studies with 579 patients (278 men, 301 women) and 631 metastatic pelvic lesions were included in the study. The mean follow-up range was 0.7 to 26.4 months. Percutaneous cementation alone was performed in 441 patients (76.2%). Supplemental ablative procedures were performed in 77 patients (13.3%), and supplemental internal fixation using cannulated screws was performed in 107 patients (18.5%). Twelve studies with 430 patients (74.2%) reported pain-related and/or functional outcome scores, of which all studies reported overall clinically notable improvement at short-term follow-up. All studies reported periprocedural complications. Local cement leakage was the most common complication (162/631 lesions, 25.7%) followed by transient local pain (25/579 patients, 4.3%). There were no reported cases of major complications. Seven patients (1.2%) underwent re-intervention for persistent symptoms. CONCLUSIONS: Percutaneous cementation may be an effective method for treating pain and function related to pelvic metastasis. The most common complication was cement leakage surrounding the lesion. The rates of major complications were low, and most complications appeared minor and transient. Additional prospective studies are needed to further assess the efficacy of this procedure. LEVEL OF EVIDENCE: IV, systematic review of level I to IV therapeutic studies.

Customized 3-dimensional-printed Vertebral Implants for Spinal Reconstruction After Tumor Resection: A Systematic Review.

STUDY DESIGN: Systematic review. OBJECTIVE: To examine the outcomes of customized 3-dimensional (3D) printed implants for spinal reconstruction after tumor resection. SUMMARY OF BACKGROUND DATA: Various techniques exist for spinal reconstruction after tumor resection. Currently, there is no consensus regarding the utility of customized 3D-printed implants for spinal reconstruction after tumor resection. MATERIALS AND METHODS: A systematic review was registered with PROSPERO and performed according to "Preferred Reporting Items for Systematic Reviews and Meta-analyses" guidelines. All level I-V evidence studies reporting the use of 3D-printed implants for spinal reconstruction after tumor resection were included. RESULTS: Eleven studies (65 patients; mean age, 40.9 ± 18.1 y) were included. Eleven patients (16.9%) underwent intralesional resections with positive margins and 54 patients (83.1%) underwent en bloc spondylectomy with negative margins. All patients underwent vertebral reconstruction with 3D-printed titanium implants. Tumor involvement was in the cervical spine in 21 patients (32.3%), thoracic spine in 29 patients (44.6%), thoracolumbar junction in 2 patients (3.1%), and lumbar spine in 13 patients (20.0%). Ten studies with 62 patients reported perioperative outcomes radiologic/oncologic status at final follow-up. At the mean final follow-up of 18.5 ± 9.8 months, 47 patients (75.8%) had no evidence of disease, 9 patients (14.5%) were alive with recurrence, and 6 patients (9.7%) had died of disease. One patient who underwent C3-C5 en bloc spondylectomy had an asymptomatic subsidence of 2.7 mm at the final follow-up. Twenty patients that underwent thoracic and/or lumbar reconstruction had a mean subsidence of 3.8 ± 4.7 mm at the final follow-up; however, only 1 patient had a symptomatic subsidence that required revision surgery. Eleven patients (17.7%) had one or more major complications. CONCLUSION: There is some evidence to suggest that using customized 3D-printed titanium or titanium alloy implants is an effective technique for spinal reconstruction after tumor resection. There is a high incidence of asymptomatic subsidence and major complications that are similar to other methods of reconstruction. LEVEL OF EVIDENCE: Level V, systematic review of level I-V studies.

Characterizing neck injuries in the national football league: a descriptive epidemiology study.

BACKGROUND: Neck injury is a common and often debilitating injury among athletes participating in American football. Limited data exists regarding neck injuries among elite athletes in the National Football League (NFL). To characterize the epidemiology of non-season ending, season-ending, and career-ending neck injuries in the NFL from 2016 through 2021. METHODS: Athletes who sustained neck injuries were identified using the NFL's injured reserve (IR) list between the 2016 and 2021 seasons. Demographics and return to sport (RTS) data were collected. Available game footages were reviewed to identify the mechanism of injury (MOI). Injury incidence rates were calculated based on per team play basis. RESULTS: During the 6-year study period, 464 players (mean age 26.8 ± 3.2 years) were placed on the injury reserve list due to neck injuries. There were 285 defensive players and 179 offensive players injured (61.4 vs 38.6%, respectively, p < 0.001). Defensive back was the most common position to sustain a neck injury (111 players, 23.9%). 407 players (87.7%) sustained non-season-ending injuries with a mean RTS at 9.2 ± 11.3 days. 36 players (7.8%) sustained season-ending injuries with a mean RTS at 378.6 ± 162.0 days. 21 players (4.5%) sustained career-ending injuries. The overall incidence of neck injuries was 23.5 per 10,000 team plays. The incidence of season-ending injuries and career-ending injuries were 1.82 and 1.06 per 10,000 team plays, respectively. There were 38 injuries with available footages for MOI assessment (23 non-season-ending, 9 season-ending, 6 career-ending). Head-to-head contact was seen in 15 injuries (39.5%), head-down tackling in 11 injuries (28.9%), direct extremity-to-head contact in 7 injuries (18.4%), and head-to-ground contact in 5 injuries (13.2%). There was no significant difference in age, position, or MOI among players sustaining non-season-ending, season-ending, and career-ending injuries. CONCLUSION: There is a high incidence of neck injuries among NFL athletes with predictable MOIs including head-to-head contact, head-down tackling, direct extremity-to-head contact, and head-to-ground contact. Defensive players were more likely to sustain neck injuries compared to offensive players. Defensive back was the most common position to sustain a neck injury. LEVEL OF EVIDENCE: III.

The Use of Photodynamic Bone Stabilization to Tamponade Bleeding in a Pathologic Humeral Shaft Fracture: A Case Report.

Introduction: Hypervascular tumors such as renal and thyroid carcinoma have a significant risk of intraoperative bleeding. To help mitigate bleeding, interventional preoperative embolization is traditionally used; however, it is success is highly variable. This is the first case report to discuss using expandable balloon implants with a minimally invasive approach to achieve fracture fixation and tamponade acute intraoperative bleeding. Case Report: A 48-year-old male with clear-cell renal cell carcinoma presented with a left humeral shaft pathologic fracture. The patient was scheduled to undergo open biopsy, curettage of tumor, and fracture fixation with an intramedullary device. Intraoperatively, during open biopsy and curettage, brisk bleeding was encountered, which ceased after inserting an intramedullary photodynamic bone stabilization implant (IlluminOss). The implant's balloon expanded to the diameter of the humerus allowing for tamponade, fracture stability, and a minimally invasive approach. Conclusion: We present a possible intraoperative option for achieving control of bleeding in pathologic long bone fractures by deploying a photodynamic stabilization device. The method described can have applications in specific patients and obviate the need for pre-operative embolization for highly vascular tumors due to the implant's ability to create tamponade within the bone.

Anterior column realignment (ACR) for focal kyphotic spinal deformity using an anterior to psoas approach and anterior longitudinal ligament release.

Background: The anterior-to-psoas (ATP) approach to the lumbar spine has been proposed as an alternative to the transpsoas approach for approaching the disc space without dissecting through the psoas muscle, thus decreasing the risk of injury to the lumbar plexus. There are no prior studies that evaluates the clinical application of anterior longitudinal ligament (ALL) release and anterior column realignment (ACR) using the ATP approach. The objective of this study was to describe and evaluate the safety of ACR using an ATP approach with release of both the ALL and bilateral annulus for correction of a focal kyphotic lumbar deformity. Methods: A retrospective analysis of fourteen consecutive patients at a single institution between January 2017 and December 2019 of patients undergoing ACR using an ATP approach for lumbar flatback syndrome with focal kyphotic lumbar deformity by a single surgeon was performed. Primary outcome measures were pre- and postoperative radiographic parameters. Secondary outcome measures were perioperative adverse events (AEs), 30-day readmissions/reoperations, discharge disposition, post-operative length of stay (LOS), and radiographic complications. Results: Fourteen consecutive patients (mean age 67.0±3.9 years, 8 males, 6 females) with 15 total ACR levels were included in the study. A grade 1 posterior column osteotomy (PCO) with posterior instrumentation was performed at all ACR levels. L2-L3 ACR was performed in nine patients, L3-L4 in four patients, and L4-L5 in two patients. Mean preoperative disk lordotic angle at the ACR level was 5.4°±5.9° of kyphosis. Mean increase in postoperative disk lordotic angle was 24.0°±8.5° at a mean follow-up of 34.0±23.4 months. Conclusions: ACR can be performed with a complete ALL release under direct visualization using the ATP approach. This technique can be a safe and effective method for achieving substantial correction of a focal kyphotic deformity within the lumbar spine.

Regulation of autophagy by DNA G-quadruplexes.

Guanine-rich DNA strands can form secondary structures known as G-quadruplexes (G4-DNA or G4s). G4-DNA is important for the regulation of replication and transcription. We recently showed that the expression of Atg7, a gene that is critical for macroautophagy/autophagy, is controlled by G4-DNA in neurons. We demonstrated that the transcription factor SUB1/PC4 and the G4-DNA-specific antibody HF2 bind to a putative G4-DNA motif located in the Atg7 gene. Stabilizing G4-DNA with the G4-ligand pyridostatin (PDS) downregulates Atg7 expression in neurons. Here, we further investigated how G4-DNA in the Atg7 gene is stabilized by PDS. We show that PDS can form 1:1 and 2:1 complexes with the Atg7's G4. We also demonstrate that PDS downregulates the ATG7 protein and the expression of Atg7 in astrocytes as well as in neurons. Together with our previous findings, these data establish a novel G4-DNA-associated mechanism of autophagy regulation at a transcriptional level in neurons and astrocytes.