Minimally invasive treatment of unstable pelvic ring injuries with modified pedicle screw-rod fixator.

Objective To evaluate the clinical application of the minimally invasive modified pedicle screw-rod fixator for unstable pelvic ring injuries, including its feasibility, merits, and limitations. Methods Twenty-three patients (13 males, 10 females; average age, 36.3 years) with unstable pelvic ring injuries underwent anterior fixation using a modified pedicle screw-rod fixator with or without posterior fixation using a transiliac internal fixator. The clinical findings were assessed using Majeed scores. The quality of reduction was evaluated using the Matta criteria. Results Clinical results at 1 year postoperatively were excellent in 14 patients, good in 7, and fair in 2. The two patients with fair results had intermittent pain at the sacroiliac joint because of the posterior implant. One woman complained of persistent pain at the pubic tubercle during sexual intercourse. Iatrogenic neuropraxia of the unilateral lateral femoral cutaneous nerve occurred in three patients. Unilateral femoral nerve palsy occurred in one patient. The quality of fracture reduction was excellent in 12 patients, good in 8, and fair in 3. Heterotopic ossification occurred in eight patients; all were asymptomatic. Conclusions Minimally invasive modified pedicle screw-rod fixation is an effective alternative treatment for pelvic ring injuries.

[Therapeutic observation of subcutaneous pedicle screw-rod system with modified placement for Tile B pelvic fractures].

OBJECTIVE: To investigate the feasibility and therapeutic effect of subcutaneous pedicle screw-rod system with modified placement in treatment of Tile B pelvic fractures. METHODS: From June 2014 to August 2015, 14 patients with Tile B pelvic fractures were treated by subcutaneous pedicle screw-rod system with modified placement in the anterior inferior iliac spine and pubic tubercle. There were 8 males and 6 females, aged from 23 to 65 years with an average of 42 years. Operative time, intraoperative blood loss, fracture healing and postoperative complication were observed and clinical effects were evaluated by Matta reduction standard and Majeed score. RESULTS: All patients were followed up from 8 to 15 months with an average of 10.5 months. Operative time was 25 to 45 min with an average of 32 min;intraoperative blood loss was 10 to 35 ml with an average of 18 ml. All fractures got primary healing and healed time was 9 to 14 weeks with an average of 12.5 weeks. No postoperative incision infection, internal fixation failure and ectopic ossification were found, 4 cases occurred unilateral lateral femoral cutaneous nerve injury and 1 case occurred unilateral femoral nerve paralysis, but all restored finally. According to Matta criteria, reduction was excellent in 7 cases, good in 5 cases, fair in 2 case. According to Majeed score system, the functional evaluation at last follow-up was excellent in 5 cases, good in 7 cases, fair in 2 cases with the average score of 81.50±8.05. CONCLUSIONS: Subcutaneous pedicle screw-rod system with modified placement in the anterior inferior iliac spine and pubic tubercle have advantages of strong reduction, less trauma and complications, and is a promising surgical method in the treatment of Tile B pelvic fractures.

Insulin-like growth factor 1 antagonizes lumbar disc degeneration through enhanced autophagy.

Autophagy has been shown to antagonize the development of Lumbar disc degeneration (LDD), whereas the molecular regulation of autophagy is unknown. We recently reported a potential role of Insulin-like growth factor 1 receptor (IGF1R)/phosphatidylinositol-3 kinase (PI3k)/Akt signaling in the initiation and progression of LDD. Here, we studied the effects of IGF1R signaling on disc cell autophagy. We showed a correction of activation of IGF1R and disc cell autophagy in the resected discs in LDD patients. In vitro, activation of IGF1R signaling antagonized the decreases in cell viability of human disc cells, HNPSV, through suppression of apoptosis and enhancement of autophagy. Suppression of IGF1R signaling or inhibition of autophagy abolished the effects of activation of IGF1R signaling on disc cell survival upon compression. Together, our data suggest that activation of IGF1R may antagonize LDD, at least partially through enhanced autophagy.

Regulation of insulin-like growth factor 1 receptor signaling by microRNA-4458 in the development of lumbar disc degeneration.

A potential role of Insulin-like growth factor 1 (IGF1) receptor/phosphatidylinositol-3 kinase (PI3k)/Akt signaling in the initiation and progression of Lumbar disc degeneration (LDD) has been recently reported. However, the regulation of IGF1 receptor (IGF1R) at post-transcriptional levels in the development of LDD remains unknown. Here, we studied the effects of microRNA-4458 on the expression of IGF1R. We examined the IGF1R levels and microRNA-4458 (miR-4458) levels in the resected LDD discs, compared with the traumatized, non-LDD discs. We analyzed the binding of miR-4458 to the 3'-UTR of IGF1R mRNA and its effects on IGF1R translation by bioinformatics analysis and by luciferase-reporter assay, respectively. We modified miR-4458 levels in a human nucleus pulposus SV40 cell line (HNPSV), and examined the effects of miR-4458 on the expression of IGF1R and Akt, as well as their phosphorylation. We found that the levels of miR-4458 were significantly higher and the levels of IGF1R were significantly lower in LDD discs, compared with the control non-LDD discs. The levels of IGF1R inversely correlated with the levels of miR-4458 in LDD discs. Moreover, miR-4458 was found to bind to the 3'-UTR of IGF1R mRNA to prevent its translation. In miR-4458-modified HNPSV cells, we found that miR-4458 decreased both total IGF1R and phosphorylated IGF1R, resulting in deceases in phosphorylated Akt. Thus, these data suggest that miR-4458 may suppress PI3k/Akt signaling pathway through 3'-UTR-inhibtion of IGF1R mRNA to promote development of LDD.