Engineered bone tissue to recreate the continuity of damaged skeletal segments is one of the field of interest of tissue engineering. Trabecular titanium has very good mechanical properties and high in vitro and in vivo biocompatibility: it can be used in biomedical applications to promote osteointegration demonstrating that it can be successfully used for regenerative medicine in orthopaedic surgery (1). Purpose of this investigation was to evaluate the behavior of adipose tissue derived stem cells (hASCs) cultured on scaffolds of Trabecular TitaniumTM (Lima-Lto) (TT). hASCs are considered to be multipotent mesenchymal stem cells that are easily induced to differentiate into functional osteoblasts both in vitro and in vivo (2). The hASCs were obtained from the subcutaneous adipose tissue of healthy donors during total hip replacement procedures after digestion with collagenase. They were seeded on monolayer and on the TT scaffolds, and incubated at 37 degrees C in 5% CO2 with osteogenic medium or control medium. The expression of bone-related genes using RT-PCR, time course of alkaline phosphatase activity and morphological investigation with Scanning Electron Microscopy (SEM) were performed to evaluate the osteogenic differentiation of hASCs. Alkaline phosphatase activity, marker of the differentiation toward the osteogenic pattern, was significantly higher in hASCs grown with osteogenic medium than in cells grown with control medium, both in monolayer and TT scaffolds; moreover, also alkaline phosphatase of hASCs grown on TT scaffolds in the presence of control medium increased with time, differently from that of cells grown on monolayer. The osteogenic differentiated hASCs expressed the bone-related genes type I collagen, osteocalcin, Runx-2 and alkaline phosphatase. SEM observations showed that hASCs differentiated toward osteoblast-like cells: they produced a big amount of extracellular matrix that covered the surface of the porous scaffolds with bridges between the pore walls. These data suggest that hASCs are able to adhere to TT scaffolds, to acquire an osteoblastic phenotype and to produce abundant extracellular matrix, with but also without osteogenic medium. We can therefore conclude that this material carries osteinductive properties being responsible of ostegenic differentiation; consequently, this scaffold/cells construct is effective to regenerate damaged tissue and to restore the function of bone tissue

INTRODUCTION. The purpose of this study is to report results from a prospective multicenter study of a bioresorbable type I collagen scaffold used to replace tissue loss following irreparable lateral meniscus injuries. METHODS. 49 non-consecutive patients (33M/16F; mean age 30.5 yrs, range 14.7–54.7 yrs) with irreparable lateral meniscus tears or loss requiring surgical treatment were prospectively enrolled at one of 7 EU centers. 11 patients (22%) had acute injuries of the lateral meniscus, while 38 (78%) had prior surgeries to the involved meniscus. Implantation of the LCMI (now Lateral Menaflex) was performed arthroscopically using an all-inside suturing technique (FASTFIX) combined with inside-out sutures in the more anterior meniscus aspect. Forty-three patients were evaluated with a 2 to 4-year follow-up (FU); mean FU duration was 45 months (range, 33–53 m). Patients were evaluated clinically and by self-assessment using Tegner activity and Lysholm function scores, as well as the Visual Analog Scales (VAS) for pain, and a satisfaction questionnaire. Evaluations were performed pre-operatively, 6 months, 1 year, 2 and 4 years after surgery. X-ray and/or MR-images were taken pre-operatively, and at 1 year and 2 years after surgery. RESULTS. At 3 months after surgery, all patients were able to return to activities of daily living without limitation. Post-op. mean values of all evaluated patients showed statistically significant improvement compared to the preoperative scores. Mean Tegner scores increased from 3.0 to 5.2 at 4 years (0.8 points less than the pre-injury “recall” value); mean Lysholm improved from 63 to 91; mean pain (VAS) decreased from 36 to 8. At the 4-year time point, 86% of the patients stated that they were satisfied with their results (compared to 78% at the one year FU time point). Function and pain scores improved continuously with the highest score at the latest FU evaluation. All data were statistically significant (p<0.001, except for Tegner with p=0.03). MRI examination revealed no changes to the articular cartilage and joint space; however, the newly formed tissue did not present a signal consistent with fully mature native meniscus tissue. Reoperations were necessary in 5 patients (10%) during the FU time period: 3 of the reoperations were for persistent swelling and pain, which were classified as related to the device (6%) and were treated by synovectomy and debridement. Patients recovered without sequelae. The re-op. rate in this series is comparable to re-op. rates reported after lateral meniscal repair. DISCUSSION. Based on available results with a minimum 2 year FU, 90% of the patients benefited from the Lateral Menaflex as evidenced by improved clinical outcomes associated with gains in activity and function. Longer-term FU continues to determine the extent and duration of the benefits observed

Aims

Little is known about the effect of haemorrhagic shock and resuscitation on fracture healing. This study used a rabbit model with a femoral osteotomy and fixation to examine this relationship.

This multicentre prospective clinical trial aimed to determine whether early administration of alendronate (ALN) delays fracture healing after surgical treatment of fractures of the distal radius. The study population comprised 80 patients (four men and 76 women) with a mean age of 70 years (52 to 86) with acute fragility fractures of the distal radius requiring open reduction and internal fixation with a volar locking plate and screws. Two groups of 40 patients each were randomly allocated either to receive once weekly oral ALN administration (35 mg) within a few days after surgery and continued for six months, or oral ALN administration delayed until four months after surgery. Postero-anterior and lateral radiographs of the affected wrist were taken monthly for six months after surgery. No differences between groups was observed with regard to gender (p = 1.0), age (p = 0.916), fracture classification (p = 0.274) or bone mineral density measured at the spine (p = 0.714). The radiographs were assessed by three independent assessors. There were no significant differences in the mean time to complete cortical bridging observed between the ALN group (3.5 months (se 0.16)) and the no-ALN group (3.1 months (se 0.15)) (p = 0.068). All the fractures healed in the both groups by the last follow-up. Improvement of the Quick-Disabilities of the Arm, Shoulder and Hand (QuickDASH) score, grip strength, wrist range of movement, and tenderness over the fracture site did not differ between the groups over the six-month period. Based on our results, early administration of ALN after surgery for distal radius fracture did not appear to delay fracture healing times either radiologically or clinically.

Cite this article: Bone Joint J 2013;95-B:1544–50.

Systemic antibiotics reduce infection in open fractures. Local delivery of antibiotics can provide higher doses to wounds without toxic systemic effects. This study investigated the effect on infection of combining systemic with local antibiotics via polymethylmethacrylate (PMMA) beads or gel delivery.

An established Staphylococcus aureus contaminated fracture model in rats was used. Wounds were debrided and irrigated six hours after contamination and animals assigned to one of three groups, all of which received systemic antibiotics. One group had local delivery via antibiotic gel, another PMMA beads and the control group received no local antibiotics. After two weeks, bacterial levels were quantified.

Combined local and systemic antibiotics were superior to systemic antibiotics alone at reducing the quantity of bacteria recoverable from each group (p = 0.002 for gel; p = 0.032 for beads). There was no difference in the bacterial counts between bead and gel delivery (p = 0.62).

These results suggest that local antibiotics augment the antimicrobial effect of systemic antibiotics. Although no significant difference was found between vehicles, gel delivery offers technical advantages with its biodegradable nature, ability to conform to wound shape and to deliver increased doses. Further study is required to see if the gel delivery system has a clinical role.

Cite this article: Bone Joint J 2015;97-B:1423–7.

Objectives

The biomembrane (induced membrane) formed around polymethylmethacrylate (PMMA) spacers has value in clinical applications for bone defect reconstruction. Few studies have evaluated its cellular, molecular or stem cell features. Our objective was to characterise induced membrane morphology, molecular features and osteogenic stem cell characteristics.