Evaluation the results of anterior cruciate ligament reconstruction with or without using antibiotic solution during graft preparation.

INTRODUCTION: Joint infection after Anterior Cruciate Ligament (ACL) reconstruction is an uncommon infection which can affect joint movement and function. In this study, the impact of using antibiotic during graft preparation on the results of ACL reconstruction was investigated to examine the negative effects of antibiotic solution on graft and clinical symptoms after the surgery. METHODS: In this randomized clinical trial study, 80 patients were enrolled. In one group, the graft was placed in vancomycin solution (500 mg of vancomycin powder in 100 ml of normal saline) for 10-15 min during the surgery. In other group, the surgery was performed routinely and the graft was not placed in antibiotic solution. Intravenous antibiotic was given to both groups and they underwent ACL reconstruction surgery through arthroscopic transportal technique using their hamstring tendon. Symptoms and examinations of patients were evaluated for one year after the surgery. RESULTS: There was no difference between two groups in terms of knee dislocation, knee lock, pain, fever, positivity of Lachman test, Anterior drawer test and pivot-shift test, knee swelling, and movement restriction in flection and extension (P > 0.05). No infection was seen in patients. CONCLUSIONS: Placing grafts in vancomycin solution does not have negative effects on graft quality and results of ACL surgery.

Clinical and histopathological outcome of cervical and chest MRI involving non-MRI-conditional cardiac pacemakers: a study using sheep models.

AIM: To examine the clinical and histopathological consequences of MRI in sheep implanted with non-MRI-conditional cardiac pacemakers. MATERIALS AND METHODS: Under general anesthesia, active fixation leads of two dual-chamber, non-MRI-conditional cardiac pacemakers (St. Jude Medical and Medtronic) were implanted either at the right ventricular apex or at the right atrium of two male sheep and connected to the V and A channels of the pacemakers, respectively. The generators were placed in cervical subcutaneous pockets. On day 5, both sheep underwent 1.5 T cervical and chest MRI with continuous electrocardiogram monitoring. Obtained sequences were T1-weighted (T1W), T2-weighted (T2W), T2-gradient echo and diffusion weighted (DW). The employed modes were OVO, VOO and VVI for one sheep and OAO, AOO and AAI for the other (unipolar and bipolar configuration of pacing and sensing for both). Battery impedance, pacing lead impedance, intrinsic amplitude and capture thresholds were checked at baseline and after each sequence, as well as 48 h after imaging. Histopathological examination of the cardiac tissue around the lead tip was performed 4 weeks post-imaging. RESULTS: No significant changes in device position or configuration were observed during or after MRI. Clinical outcome was uneventful in both sheep. Minor inflammatory and necrotic changes were reported after histopathological examination of the cardiac tissue around the lead tip. CONCLUSION: 1.5 T MRI of two implanted non-MRI-conditional pacemakers was found safe in terms of device configuration and stability, clinical outcome and cardiac tissue histopathological findings.

The impacts of internal versus external fixation for tibial fractures with simultaneous acute compartment syndrome.

PURPOSE: High-energy tibial fractures may cause compartment syndrome, which needs fasciotomy. However, in this procedure, close fractures become an open wound and choosing the best type of fixation for this situation has been a problem. We assumed early open reduction and internal fixation (ORIF) instead of late internal fixation or external fixation, or stage-based approach is a better method. METHODS: We collected fifty-seven medical records from 2012 to 2017 stored in Alzahra and Kashani University Hospital databases. We selected important information of their medical files, called the submitted phone numbers, and asked them to come to our clinic and examined their leg for any malunion and/or movement restriction postoperatively. We asked about pain and paresthesia in their leg. Twelve cases were excluded. RESULTS: Demographic variables were not significantly different between these two groups. Deep infection, malunion, decreased range of motion in both knee and ankle joints, pain and paresthesia mainly occurred in external fixation group, except malunion (p value = 0.032), other variables were not statistically significant between two groups. More surgeries were performed predominantly for external fixation group (p value < 0.001). External fixation stayed 4.7 days longer at hospital although it was not statistically significant (p value = 0.108). CONCLUSION: It is better to perform fasciotomy and ORIF simultaneously in one surgery to lower the number of surgeries, days of hospitalization, decrease the risk of deep infection, malunion and movement restriction although its postoperative outcomes were not considerably different from external fixation. We indicate that stage-based approach is accompanied by poor outcomes and lesser satisfaction.

Enzymatically gellable gelatin improves nano-hydroxyapatite-alginate microcapsule characteristics for modular bone tissue formation.

To maintain gelatin (Gel) as adhesive motifs inside alginate microcapsule as building blocks of modular approach, phenol moiety (Ph) was introduced into gelatin (Gel Ph). Addition of Gel Ph to alginate (Alg-Gel Ph) dramatically altered the physical properties of alginate-based hydrogels as compared to unmodified gelatin (Alg-Gel) addition. Alg-Gel Ph hydrogels revealed a dramatically lower swelling ratios (63%) as compared to Alg-Gel hydrogels (150%). Moreover, Gel Ph decreased 40% degradation rate of alginate-based hydrogels after 72 hr, while increasing compressive modulus 3.5-fold as compared to Alg-Gel hydrogels. Introducing nano-hydroxyapatite (nHA) to Alg-Gel Ph hydrogel (Alg-Gel Ph-nHA) could reduce degradation rate to 41.5% and improve compressive modulus of hydrogels significantly, reaching to 294 ± 2.5 kPa. The microencapsulated osteoblast-like cells proliferated considerably and showed more metabolic activities (two times) in Alg-Gel Ph-nHA microcapsules during a 21-day culture period, resulting in more calcium deposition and alkaline phosphatase (ALP) activities. The subcutaneous microcapsules could also be identified readily without complete absorption and signs of toxicity or any untoward reactions and viable osteoblast-like cells were seen as red colored areas in the central regions of cell-laden microcapsules after 1 month. The study demonstrated Alg-Gel Ph-nHA microcapsule as a promising 3D microenvironment for modular bone tissue formation.

Gelatin improves peroxidase-mediated alginate hydrogel characteristics as a potential injectable hydrogel for soft tissue engineering applications.

To develop an efficient injectable alginate-based hydrogel for soft tissue engineering applications, phenol moiety (Ph) was introduced into alginate (Alg-Ph), and the influence of gelatin as cell adhesive molecule was evaluated on the peroxidase-mediated alginate hydrogel properties and cultured chondrocytic cell behavior. Addition of gelatin (1.5% w/v) to Alg-Ph (1.5% w/v) hydrogels (Alg-Ph/gelatin) regulated characteristics of the enzymatically gellable alginate hydrogel with increasing gelation time to 5.1 min (76%). Swelling ratio and degradation rates of the Alg-Ph/gelatin hydrogel also increased 60 and 100%, respectively, while the mechanical strength value was 35% less than the Alg-Ph hydrogel. Scanning electron microscopy images showed that the addition of gelatin could also increase uniformity of pore sizes inside the Alg-Ph/gelatin hydrogels. The chondrocyte cells maintained their original phenotype and revealed statistically more metabolic activities in the Alg-Ph/gelatin hydrogel. Hydrogels subscutaneously implanted in rats could also be identified readily without complete absorption and signs of toxicity or any untoward reactions after 1 month. Viable chondrocyte cells inside globular aggregates were seen as red colored areas in the cell-laden hydrogels. The study demonstrates that enzymatically gellable alginate/gelatin hydrogel has fair potential as a natural-based injectable hydrogel for soft tissue engineering applications.

Leukocyte and Platelet Rich Plasma (L-PRP) Versus Leukocyte and Platelet Rich Fibrin (L-PRF) For Articular Cartilage Repair of the Knee: A Comparative Evaluation in an Animal Model.

BACKGROUND: Articular cartilage injuries of the knee are among the most debilitating injuries leading to osteoarthritis due to limited regenerative capability of cartilaginous tissue. The use of platelet concentrates containing necessary growth factors for cartilage healing has recently emerged as a new treatment method. OBJECTIVES: The efficacy of two types of different platelet concentrates were compared in the treatment of acute articular cartilage injuries of the knee in an animal model. MATERIALS AND METHODS: Eighteen adult Iranian mixed breed male dogs were used to conduct this experimental study. Full thickness articular cartilage defects (diameter 6 mm, depth 5 mm) were created in the weight bearing area of femoral condyles of both hind limbs in all dogs (n = 72). Twelve dogs were randomly selected to receive treatment and their right and left hind limb defects were treated by L-PRP and L-PRF implantation respectively, while no treatment was undertaken in six other dogs as controls. The animals were euthanized at 4, 16 and 24 weeks following surgery and the resultant repair tissue was investigated macroscopically and microscopically. At each sampling time, 4 treated dogs and 2 control dogs were euthanized, therefore 8 defects per group were evaluated. RESULTS: Mean macroscopic scores of the treated defects were higher than the controls at all sampling times with significant differences (P < 0.05) observed between L-PRF treated and control defects (10.13 vs. 8.37) and L-PRP treated and control defects (10 vs. 8.5) at 4 and 16 weeks, respectively. A similar trend in mean total microscopic scores was observed with a significant difference (P < 0.05) between L-PRP treated and control defects at 4 (9.87 vs. 7.62) and 16 (13.38 vs. 11) weeks. No significant difference was observed between the platelet concentrate treated defects in either mean macroscopic scores or mean total microscopic scores. CONCLUSIONS: Both L-PRP and L-PRF could be used to effectively promote the healing of articular cartilage defects of the knee.

Effect of autologous platelet rich fibrin on the healing of experimental articular cartilage defects of the knee in an animal model.

The effect of autologous platelet rich fibrin (PRF), a second generation platelet product, on the healing of experimental articular cartilage lesions was evaluated in an animal model. Full thickness cartilage lesions with a diameter of 6 mm and depth of 5 mm were created in the weight bearing area of femoral condyles of both hind limbs in 12 adult mixed breed dogs. Defects in the left hind limb of each dog were repaired by PRF implantation whereas those in the right hind limb were left empty. The animals were euthanized at 4, 16, and 24 weeks following surgery and the resultant repair tissue was investigated macroscopically and microscopically. The results of macroscopic and histological evaluations indicated that there were significant differences between the PRF treated and untreated defects. In conclusion, the present study indicated that the use of platelet rich fibrin as a source of autologous growth factors leads to improvement in articular cartilage repair.