Percutaneous endoscopic transforaminal discectomy for the treatment of L5-S1 lumbar disc herniation and the influence of iliac crest height on its clinical effects.

The present study aimed to explore the clinical effects of percutaneous endoscopic transforaminal discectomy using a transforaminal endoscopic spine system (TESSYS) technique for the treatment of L5-S1 lumbar disc herniation and to analyse the influence of iliac crest height on these clinical effects. The clinical data of 76 patients with L5-S1 single-segment disc herniation treated with TESSYS at The Second Affiliated Hospital and Third Affiliated Hospital of Xi'an Jiaotong University between January and December 2016 were retrospectively analysed. Patients were divided into the following three groups according to the positional relation between the highest point of the iliac crest and the L4 and L5 pedicles in the lateral lumbar, as determined by X-ray: Group I, iliac crest height below the upper edge horizontal line of the L5 pedicle (n=42); group II, iliac crest height between the lower edge horizontal line of the L4 pedicle and the upper edge horizontal line of the L5 pedicle (n=29) and group III, iliac crest height above the lower edge horizontal line of the L4 pedicle (n=5). Changes in the postoperative visual analogue scale (VAS) pain score and Oswestry disability index (ODI) of the lower back and lower limbs were observed, and the effects were compared among the three groups. The mean operating time was 86.5±13.5 min. A single patient experienced cerebrospinal fluid leakage due to a mild tear of the dura mater during the operation, which improved after symptomatic treatment. The same operation was repeated in one patient due to the recurrence of disc herniation. In all patients, the VAS pain score and ODI of the lower back and lower limbs at 1 week and 1, 3 and 12 months following the operation were significantly lower than those before the operation (all P<0.05). Furthermore, the postoperative VAS pain score and ODI of the lower back and lower limbs were poorer in group III (L5-S1 lumbar disc herniation complicated with high iliac crest) than in groups I and II (P<0.05). These results suggested that TESSYS was effective in treating lumbar disc herniation. Whether the iliac crest is higher than the lower edge horizontal line of the L4 pedicle is suggested to be one of the factors influencing the outcome of the operation.

Resveratrol prevents steroid-induced osteonecrosis of the femoral head via miR-146a modulation.

The purpose of this study was to investigate the possible use of resveratrol (Res) to reverse abnormal osteogenesis/osteoclastogenesis activity that occurs during femoral head osteonecrosis and to explore the detailed mechanisms. Application of Res to bone marrow-derived mesenchymal stem cells in vitro promoted survival, inhibited apoptosis, and downregulated expression of reactive oxygen species expression. Moreover, Res application was associated with elevated microRNA-146a (miR-146a) expression, osteogenic differentiation, and suppressed osteoclastic differentiation, which were markedly reversed by miR-146a inhibitor. Histopathological observations and micro-computed tomography scanning results indicated that the Res-treated group had lower incidence of osteonecrosis and better bone microstructure than the untreated group. Res inhibited osteoclastogenesis through altering the levels of sirtuin1 (Sirt1), nuclear transcription factor-κB (NF-κB), and receptor activator of NF-κB ligand (RANKL). Simultaneously, Res treatment improved bone formation and increased ß-catenin and runt-related transcription factor 2 (Runt2) expression levels, while reducing forkhead box class O (FOXO) family protein levels. The results of our study suggest that Res prevents steroid-induced osteonecrosis by upregulating miR-146a, and thereby stabilizes osteogenesis/osteoclastogenesis homeostasis via Wnt/FOXO and Sirt1/NF-κB pathways.

Effects of Unilateral Tourniquet Used in Patients Undergoing Simultaneous Bilateral Total Knee Arthroplasty.

OBJECTIVE: To assess the benefits of use of a tourniquet in one limb in patients undergoing simultaneous bilateral total knee arthroplasty (TKA). METHODS: A prospective randomized trial was designed to evaluate the outcomes of unilateral tourniquet use during simultaneous bilateral TKA. A total of 52 (36 women and 16 men) patients with osteoarthritis who underwent simultaneous bilateral primary TKA between January 2010 and January 2015 were assigned randomly to tourniquet (TG) or non-tourniquet (NG) groups prior to surgery. Operating time, pain score, range of motion, first active straight-leg raise time, swelling, wound healing, deep vein thrombosis, and Knee Society score were observed. RESULTS: Mean operating time in the TG group was shorter than that in the NG group (P < 0.05). Postoperative pain was measured by a visual analog scale (VAS) and straight-leg raise time, which was lower and shorter in limbs operated without the use of a tourniquet (P < 0.05). In addition, this group had less postoperative swelling and lower incidence of wound complications in the early postoperative period (P < 0.05). There was no significant difference in the range of motion (ROM), deep venous thrombosis incidence, and Knee Society scores between the two groups. CONCLUSIONS: Tourniquet use in bilateral TKA can reduce intraoperative time but was associated with a higher incidence of wound complications and larger postoperative knee swelling.

[Influence of Activated Sludge Surface Properties on Flocculating Settling and Effluent Suspend Solid].

In this paper, the influence of the surface properties of the activated sludge on flocculating settling and ESS was studied in seven different sewage treatment plants in Beijing, such as the sludge volume index (SVI), the protein/carbohydrate (P/C) ratio in extracellular polymeric substance, Zeta potential, two-dimensional fractal dimension(D2f). The relationships between the surface properties of the activated sludge and flocculation ability (FA) or effluent suspend solid(ESS) were also analyzed. The results showed that no obvious correlation was obtained between SVI and FA or ESS, but obvious negative correlation between the FA and ESS (R2=0.787) was observed. When the P/C increased from 1.28 to 25.34, the FA could increase from 0.19 to 0.73 correspondingly, but the ESS decreased from 14.89 mg·L-1 to 6.08 mg·L-1. This was because the amino acids in protein with positive charge could neutralize the negative charge on the surface of floc, the increase of protein ratio in EPS could decrease the absolute value of Zeta potential, which made a contribution to form more stable floc structure, and improved the ability of flocculation. Moreover, the Zeta potential had a positive correlation with FA but a negative correlation with ESS. The absolute value of Zeta potential decreased by 1 mV, FA increased by 0.059 and ESS decreased by 0.934 mg·L-1 correspondingly. In addition, there was an obvious index correlation (R2=0.935, P<0.01) between D2f and FA; While D2f increased from 1.10 to 1.45, FA could increase by 4.3 times and ESS decreased linearly (R2=0.868).

Improved repair of bone defects with prevascularized tissue-engineered bones constructed in a perfusion bioreactor.

Vascularization of tissue-engineered bones is critical to achieving satisfactory repair of bone defects. The authors investigated the use of prevascularized tissue-engineered bone for repairing bone defects. The new bone was greater in the prevascularized group than in the non-vascularized group, indicating that prevascularized tissue-engineered bone improves the repair of bone defects. [Orthopedics. 2014; 37(10):685-690.].