Biofertilizer: The Future of Food Security and Food Safety.

There is a direct correlation between population growth and food demand. As the global population continues to rise, there is a need to scale up food production to meet the food demand of the population. In addition, the arable land over time has lost its naturally endowed nutrients. Hence, alternative measures such as fertilizers, pesticides, and herbicides are used to fortify the soil and scale up the production rate. As efforts are being made to meet this food demand and ensure food security, it is equally important to ensure food safety for consumption. Food safety measures need to be put in place throughout the food production chain lines. One of the fundamental measures is the use of biofertilizers or plant growth promoters instead of chemical or synthesized fertilizers, pesticides, and herbicides that poise several dangers to human and animal health. Biofertilizers competitively colonize plant root systems, which, in turn, enhance nutrient uptake, increase productivity and crop yield, improve plants' tolerance to stress and their resistance to pathogens, and improve plant growth through mechanisms such as the mobilization of essential elements, nutrients, and plant growth hormones. Biofertilizers are cost-effective and ecofriendly in nature, and their continuous usage enhances soil fertility. They also increase crop yield by up to about 10-40% by increasing protein contents, essential amino acids, and vitamins, and by nitrogen fixation. This review therefore highlighted different types of biofertilizers and the mechanisms by which they elicit their function to enhance crop yield to meet food demand. In addition, the review also addressed the role of microorganisms in promoting plant growth and the various organisms that are beneficial for enhancing plant growth.

Novel Repair Concept for Composite Materials by Repetitive Geometrical Interlock Elements.

Material adapted repair technologies for fiber-reinforced polymers with thermosetting matrix systems are currently characterized by requiring major efforts for repair preparation and accomplishment in all industrial areas of application. In order to allow for a uniform distribution of material and geometrical parameters over the repair zone, a novel composite interlock repair concept is introduced, which is based on a repair zone with undercuts prepared by water-jet technology. The presented numerical and experimental sensitivity analyses make a contribution to the systematic development of the interlock repair technology with respect to material and geometrical factors of influence. The results show the ability of the novel concept for a reproducible and automatable composite repair.

Fixation stability following high tibial osteotomy: a radiostereometric analysis.

Fifteen patients with varus gonarthrosis underwent high tibial osteotomy and internal fixation with an L-shaped rigid plate. In 9 patients, an average wedge size of 7.1 degrees was resected leaving the medial cortex of the proximal tibia intact (group 1). In 6 patients, the medial cortex of the proximal tibia was unintentionally fractured during surgery when an average 10.7 degrees wedge was resected (group 2). Postoperatively, patients were monitored with serial radiostereometric analysis (RSA), conventional radiographs, and clinical evaluation for 1 year. In group 2, RSA revealed a 1.3-mm increase in lateral displacement of the distal tibial segment within 3 weeks following surgery. Twelve weeks after surgery, micromotion between tibial segments was below the precision of the RSA setup in 14 of 15 patients. These findings indicate that in cases with larger wedge sizes (>8 degrees), fracture of the medial cortex of the proximal tibia was frequent and resulted in significant lateral displacement of the distal tibia relative to the tibial plateau. In such cases, prophylactic additional medial fixation rather than lateral L-plate fixation alone is advised to minimize the propensity for lateral displacement of the distal tibia and to avoid subsequent loss of correction.

Ultrasonographic evaluation at 6-month follow-up of plantar fasciitis after extracorporeal shock wave therapy.

INTRODUCTION: The aim of this study was to investigate the effect of extracorporeal shock wave therapy (ESWT) on the ultrasonographic appearance of chronically painful, proximal plantar fasciitis. MATERIALS AND METHODS: Twenty-two patients with a unilateral proximal plantar fasciitis were prospectively enrolled after unsuccessful conservative treatment lasting 6 months. The contralateral plantar fascia was used as the control. ESWT (3x3000 shock waves/session of 0.2 mJ/mm2) was performed at weekly intervals. The thickness of the plantar fascia was measured ultrasonographically about 2 cm distal of the medial calcaneal tuberosity. Pain estimation on a visual analogue scale (VAS) and the comfortable walking time were recorded. No local anaesthesia was applied. Follow-up was done at 6, 12 and 24 weeks. RESULTS: Before ESWT, the plantar fasciitis side was ultrasonographically significantly thicker than the control side (p<0.05), whereas 6 months after ESWT, the thickness of the fascia was no longer significantly different. The decrease in thickness of the plantar fasciitis side was significant (p<0.05). Pain during activities of daily living decreased by 79% according to the VAS, and the comfortable walking time increased, both significantly (p<0.01). In patients with little pain (VAS<30), the thickness of the plantar fasciitis side was significantly less (p<0.01) compared with patients who still suffered more pain (VAS>30). CONCLUSION: After ESWT, the thickness of the plantar fascia in patients with plantar fasciitis decreased, pain and walking time improved (all significantly).

Biomechanical properties of patellar and hamstring graft tibial fixation techniques in anterior cruciate ligament reconstruction: experimental study with roentgen stereometric analysis.

BACKGROUND: Reliable fixation of the soft hamstring grafts in ACL reconstruction has been reported as problematic. HYPOTHESIS: The biomechanical properties of patellar tendon (PT) grafts fixed with biodegradable screws (PTBS) are superior compared to quadrupled hamstring grafts fixed with BioScrew (HBS) or Suture-Disc fixation (HSD). STUDY DESIGN: Controlled laboratory study with roentgen stereometric analysis (RSA). METHODS: Ten porcine specimens were prepared for each group. In the PT group, the bone plugs were fixed with a 7 x 25 mm BioScrew. In the hamstring group, four-stranded tendon grafts were anchored within a tibial tunnel of 8 mm diameter either with a 7 x 25 mm BioScrew or eight polyester sutures knotted over a Suture-Disc. The grafts were loaded stepwise, and micromotion of the graft inside the tibial tunnel was measured with RSA. RESULTS: Hamstring grafts failed at lower loads (HBS: 536 N, HSD 445 N) than the PTBS grafts (658 N). Stiffness in the PTBS group was much greater compared to the hamstring groups (3500 N/mm versus HBS = 517 N/mm and HSD = 111 N/mm). Irreversible graft motion after graft loading with 200 N was measured at 0.03 mm (PTBS), 0.38mm (HBS), and 1.85mm (HSD). Elasticity for the HSD fixation was measured at 0.67 mm at 100 N and 1.32 mm at 200 N load. CONCLUSION: Hamstring graft fixation with BioScrew and Suture-Disc displayed less stiffness and early graft motion compared to PTBS fixation. Screw fixation of tendon grafts is superior to Suture-Disc fixation with linkage material since it offers greater stiffness and less graft motion inside the tibial tunnel. CLINICAL RELEVANCE: Our results revealed graft motion for hamstring fixation with screw or linkage material at loads that occur during rehabilitation. This, in turn, may lead to graft laxity.

Extracorporeal shock wave therapy (ESWT) in patients with chronic proximal plantar fasciitis: a 2-year follow-up.

The aim of this study was to compare the effect of extracorporeal shock wave therapy (ESWT) in patients with chronically painful proximal plantar fasciitis with a further conventional conservative treatment. Forty-seven patients (49 feet) with a previously unsuccessful nonsurgical treatment of at least 6 months were randomized to two groups. Heel cups had to be worn throughout the study. Group 1 (25 heels) was treated immediately with three sessions of ESWT (3000 shock waves/session of 0.2 mJ/mm2) at weekly intervals. The patients of group 2 (24 heels) continued nonsurgical treatment (iontophoresis with diclofenac and an oral nonsteroidal anti-inflammatory drug) for 12 weeks. After this period they were treated using the protocol of group 1. No significant difference of pain and walking time after further nonsurgical treatment (3 months) was seen in group 2. At 12 weeks after ESWT, the pain estimation on the visual analogue scale (VAS) for activities of daily living diminished significantly by 62.9% in group 1 and by 63.0% in group 2. The comfortable walking time had increased significantly in both groups. Two years after ESWT, pain during activities of daily living decreased by 94% in group 1 and by 90% in group 2 on the VAS and the comfortable walking time had increased significantly in both groups.

Length of the patellar tendon after anterior cruciate ligament reconstruction with patellar tendon autograft: a prospective clinical study using Roentgen stereometric analysis.

PURPOSE: This prospective study was designed to assess postoperative changes in patellar tendon length after removal of its central one third for anterior cruciate ligament (ACL) reconstruction using precise Roengen stereometric analysis (RSA). TYPE OF STUDY: Prospective clinical study. METHODS: Ten consecutive patients underwent arthroscopically assisted ACL reconstruction using the mid-third bone-patellar tendon-bone (BPTB) autograft. The tendon defect was left open and the paratenon was approximated with sutures. Tantalum beads were inserted in the distal part of the patella and in the tibial tuberosity through the bone defects. The distance between the tantalum markers in the patella and the tibial tuberosity was measured with RSA at the first day and at 1, 2, 3, 6, and 12 months after surgery. RESULTS: A decrease of patellar tendon length was observed in all cases. The amount of shortening averaged 1.6 mm (range, 0.5 to 3.2 mm), 3.2% of the initial length. In 4 patients, tendon shortening was detected during the first 4 weeks after surgery. In 6 cases, decrease of patellar tendon length started between the fourth and the eighth week. The shortening process continued in 8 knees until the 12th week. No further changes in patellar tendon length were observed after the 12th postoperative week. In 2 patients, shortening of the patella tendon exceeded 2 mm. The amount of patellar tendon shortening was not related to anterior knee pain. CONCLUSIONS: After removing the BPTB autograft, irreversible shortening of the remaining two thirds of the patellar tendon occurred during the first 12 postoperative weeks.

Femoral anatomy, computed tomography and computer-aided design of prosthetic implants.

Precise digital data of the internal femoral anatomy are necessary to develop new prosthetic implants with computer-aided design (CAD) techniques. Thirty human cadaveric femurs of central European origin were analysed by high precision computed tomography (CT) using thin slice and high resolution imaging. The CT data were image processed with thresholding to obtain a reconstruction of the cortical bone geometry. The CT threshold for cortical bone was optimized by comparison with saw cuts of macerated femurs. For each specimen a three-dimensional (3D) model of the cortical femur was calculated by the CAD system based on the processed CT data. Virtual 3D models of the 30 femurs were used to adjust a hypothetical stem to the proximal femur anatomy by repeated virtual implantations. The CAD system allowed for evaluation of anatomical parameters after hip reconstruction, amount of bone removal, and cortical bone contact. The fit and fill of the stem could be tested before clinical application and implant-related problems could be corrected.

Early failure of a press-fit carbon fiber hip prosthesis with a smooth surface.

We investigated a press-fit anatomically shaped hip stem made of carbon fiber-reinforced composite material in a prospective clinical study. The intention of the design was that a surface of interlaced carbon fibers in the proximal part would achieve metaphyseal fixation. A total of 51 carbon stems were implanted in 48 patients (30 women and 22 men). Mean age at operation was 59 years. The patients were followed clinically, radiologically, and with computed tomography. At 6-year follow-up, aseptic loosening was observed in 47 hips (92%). Forty stems were revised on average 30 months (range, 9-58 months) postoperatively. All revised carbon stems showed fibrous fixation without any bony on-growth. No osteolysis was seen. Histologically, no carbon wear or inflammatory reactions were observed. Only 4 cases had a good clinical result with bony fixation on computed tomography scan. The carbon fiber prosthesis without effective ingrowth or on-growth irregularities showed a high rate of early loosening.

Lumbosacral stability of consolidated anteroposterior fusion after instrumentation removal determined by roentgen stereophotogrammetric analysis and direct surgical exploration.

STUDY DESIGN: The intervertebral stability of bony consolidated anteroposterior lumbosacral spondylodesis is evaluated by roentgen stereophotogrammetric analysis and direct surgical exploration before and after removal of the internal fixator. OBJECTIVES: To determine the remaining in vivo stability of spinal arthrodesis solely retained by a bony integrated carbon fiber cage. SUMMARY OF BACKGROUND DATA: Roentgen stereophotogrammetric analysis studies on posterolateral lumbar fusions demonstrate primary spinal stability after additional dorsal instrumentation, which is retained during bony fusion healing. Animal models show a persistent stabilizing effect of the fixator despite the presence of bony fusion. Although direct surgical inspection is the most reliable method to evaluate fused vertebrae, roentgen stereophotogrammetric analysis has also proven to be a highly accurate method to evaluate spinal stability. METHODS: In 10 patients lumbosacral fusion was performed using carbon interbody implants and an internal fixator. Ten months after initial surgery (range 7-15 months) the internal fixation was removed to reduce local soft tissue impingement as soon as bony fusion was achieved. Fusion site exploration in the course of instrumentation removal was performed by applying distraction, compression, and torque to the grafted area under fluoroscopic control. Any motion indicated a pseudarthrosis. Lumbosacral stability was evaluated by serial roentgen stereophotogrammetric analysis after fusion and after instrumentation removal. RESULTS: During instrumentation removal the mechanical stress test under fluoroscopic control did not indicate pseudarthrosis. After instrumentation removal, roentgen stereophotogrammetric analysis measurements revealed a nonsignificant increase in lumbosacral micromotions within the fused segment with 0.14, 0.31, and 0.44 mm in the transverse, vertical, and sagittal axes, respectively. CONCLUSIONS: The internal fixator could be removed without endangering the stability of the fusion. Direct surgical exploration confirmed the adequacy of roentgen stereophotogrammetric analysis as a reliable in vivo method to evaluate lumbosacral stability after anteroposterior fusion.