Structural bone allograft fractures in oncological procedures.

Purpose: We report our experience analysing the risk of fracture amongst allografts in limb-preserving surgery for bone tumours.

Methods: We retrospectively reviewed our experience with bone allograft and its major complications when used for limb -preserving operations for bone tumours. Forty-one structural allografts were performed in 39 patients between 1992 and 2012.

Periprosthetic humeral fractures associated with reverse total shoulder arthroplasty: incidence and management.

Purpose: The purpose of this study was to record the incidence and management of periprosthetic humeral fractures (PHF) using reverse total shoulder arthroplasty (RTSA) in our institution.

Methods: We performed a retrospective study of 203 RTSA implanted in 200 patients between 2003 and 2014. The mean follow-up was 78.

Primary modular total knee replacement in severe and unstable osteoarthritis. Predictive factors for failure.

Purpose: Severe cases of osteoarthritis with ligamentous instability require the use of a modular knee arthoplasty. To assess the survival, the complications, the clinical, radiological and functional outcomes, and the quality of life of those patients in whom a Optetrak Condylar Constrained Knee (CCK) had been implanted as a primary implant. To study how the pre-operative conditions (deformity, age, sex …) and the characteristics of the arthroplasty (stems, supplements, constrained component …) could change the survival or the clinical outcomes of the implants.

In vivo tricalcium phosphate, bone morphogenetic protein and autologous bone marrow biomechanical enhancement in vertebral fractures in a porcine model.

Purpose: Minimally invasive techniques that introduce cement and bone substitutes inside the fractured vertebral body are a new treatment line with clinically proven efficacy. However, mechanical behaviours between different fillers throughout fracture evolution is yet to be clarified, as many substances are available for introduction into the vertebral body fracture.

Methods: We comparatively studied biomechanical properties of tricalcium phosphate, tricalcium phosphate with bone morphogenetic protein (rhBMP-7) and autologous bone marrow aspirate with rhBMP-7 in vivo to determine what substance is optimal for repairing vertebral lesions in a porcine model.

Fat embolism syndrome after nailing an isolated open tibial fracture in a stable patient: a case report.

Background: Fat embolism syndrome is a potentially fatal complication of long bone fractures. It is usually seen in the context of polytrauma or a femoral fracture. There are few reports of fat embolism syndrome occurring after isolated long bone fractures other than those of the femur.

Predictive factors for failure after total knee replacement revision.

Purpose: We used the Optetrak Condylar Constrained (CCK) implant, a modular and constrained knee implant as replacement for a failed primary arthroplasty, to assess the survivorship, the complications, the clinical, radiological, and functional situation, and the quality of life of those patients in whom a CCK had been implanted in recent years in order to find predictive pre-operative conditions of survival and clinical outcomes.

Methods: We performed a retrospective study of 125 CCK implanted between 1999 and 2005. The mean follow-up was nine years (range, seven to 13).

Biomechanical assays for the study of the effects of hip prostheses: application to the reconstruction of bone defects with femoral allografts.

There is a need to study and validate the mechanical behavior of the bone-implant total hip prosthesis and the treatment of its complications with experimental studies due to the limitations showed by numerical methods. Epoxy resin replicas of a femur (stereolithography) and a mechanical validation were performed. We studied three cases: intact femur (Case 1); non-defective femur with non-cemented LD primary stem (Case 2); and femur with a cavitary defect, short cemented stem over an impacted allograft (Case 3).

Midterm results of Optetrak posterior-stabilized total knee system after 7 to 12 years in a university hospital.

A clinical study has been carried out on 434 posterior-stabilized knee prostheses (Optetrak; Exactech, Gainesville, Fla) implanted between 1995 and 2000 in a university general hospital by 23 surgeons. At a mean follow-up of 8.8 years, 297 knees in 249 patients were available for review.

Recurrent total knee arthroplasty dislocation after dorsal meningioma diagnosed.

We report on a 68-year-old woman with gonarthrosis who underwent total knee arthroplasty. Having initially achieved a satisfactory result, she developed at 5 months postoperation an irreducible flexion contracture necessitating revision surgery; but no pathological findings were discovered. In the immediate postoperative period, the patient developed a severe spasm of the hamstring muscles and a paralysis of the external popliteal sciatic nerve with a posterior dislocation of the knee.

Ankle fractures with posterior malleolar fragment: management and results.

Trimalleolar ankle fractures can be difficult to manage and convey a high risk of long-term morbidity. The question of whether internal fixation of the posterior malleolar fragment is warranted remains open. We conducted a retrospective cohort study involving 45 patients who underwent surgical repair of a trimalleolar fracture.

In vivo comparison of the effects of rhBMP-2 and rhBMP-4 in osteochondral tissue regeneration.

The aim of this work is to investigate the use of bone morphogenetic proteins (rhBMP-2, rhBMP-4) alone or in combination with cells delivered in a calcium alginate gel for the treatment of osteochondral defects. For this purpose, alginate gels were prepared mixing a 2% sodium alginate solution and a 200 mM calcium chloride solution (1:1). Osteochondral defects were created (4 mm wide, 5 mm deep) in the internal femoral condyle of rabbit knee and gels were directly formed into the defects.

Oligomerization of 3,5-dimethyl benzyl alcohol promoted by clay: experimental and theoretical study.

Linear oligomerization of 3,5-dimethyl benzyl alcohol is induced by a montmorillonite clay (Tonsil Optimum Extra), producing 1,3,5,7-tetramethyl-9,10-dihydro-anthracene, which, by loss of protons results in the product 1,3,5,7-tetramethylanthracene. It was also found that the compounds 4-(3´,5´-dimethylbenzyl)-1,3,5,7-tetramethyl-9,10-dihydroanthracece and 4-(3´,5´-dimethylbenzyl)-1,3,5,7-tetra-methylanthracene were formed from 1,3,5,7-tetramethyl-9,10-dihydroanthracene. 1,3,5,7-Tetramethylanthryl radical cation was formed from 1,3,5,7-tetramethyl-9,10-dihydroanthracene; it was characterized by Electronic Paramagnetic Resonance (EPR).

Chitosan scaffolds for osteochondral tissue regeneration.

A variety of biomaterials have been introduced as potential substrates for cartilage repair. One such candidate is chitosan, which shares some characteristics with glycosaminoglycan and hyaluronic acid present in articular cartilage. Depending on chitosan source and preparation procedure, variations into its properties can be attained.

Comparative study of the use of electromagnetic fields in patients with pseudoarthrosis of tibia treated by intramedullary nailing.

We made a comparative cohort study in patients suffering from tibial pseudoarthrosis, all of whom were treated by intramedullary nailing. We divided patients into two groups: one treated by intramedullary nailing only (control group) and the other by intramedullary nailing combined with pulsed electromagnetic fields (PEMFs). The study included 57 cases of tibial pseudoarthrosis in 57 patients from February 1987 to February 2002.

The ubiquitin-proteasome pathway and viral infections in articular cartilage of patients with osteoarthritis.

Many viruses can evolve different strategies to exploit the ubiquitin-proteasome pathway (UPP) for their own benefit. Some data have recently established connections between UPP and osteoarthritis (OA). The aim of this study was to determine the possible involvement of viral infections linked with the UPP in the physiopathology of OA.

Abnormal transforming growth factor-beta expression in mesenchymal stem cells from patients with osteoarthritis.

Objective: To determine the expression of the genes that code for the isoforms of transforming growth factor-beta (TGF-beta) and TGF-beta receptors (TBR) in mesenchymal stem cells (MSC) from patients with osteoarthritis (OA).

Methods: Total RNA was extracted from primary cultures of MSC and quantitative real-time reverse transcription-polymerase chain reaction was performed to analyze gene expression.

Results: MSC from patients with OA showed significantly increased total TGF-beta, TGF-beta1 isoform, TBR-II, and TBR-III mRNA expression compared to controls.

Osteoinductive effect of bone bank allografts on human osteoblasts in culture.

Incorporation of a human bone allograft requires osteoclast activity and growth of recipient osteoblasts. The aim of this work was to study the effects produced by autoclavated and -80 degrees C frozen bone allografts on osteoblast proliferation and synthesis of interleukin 6 (IL6), activator of bone resorption, aminoterminal propeptide of procollagen I (PINP), marker of bone matrix formation, and osteoprotegerin (OPG), inhibitor of osteoclast activity and differentiation. Allografts were obtained from human femoral heads.

Study of the efficacy of coated Vicryl plus antibacterial suture in an animal model of orthopedic surgery.

Purpose: To evaluate the efficacy in vitro and in vivo of a new antibacterial suture, polyglactin 910 suture with triclosan, compared with a traditional braided suture, polyglactin (Vicryl), in a validated animal model of orthopedic infection. Our primary goal was to compare the microbiologic effectiveness of the two sutures. The secondary goal was to evaluate histopathologic signs of an inflammatory response.

Reconstruction of bone defects with impacted allograft in femoral stem revision surgery.

A retrospective clinical review was done on 54 revision hip patients. Radiological analysis examined the Gross and AAOS classifications, stem position, cement mantles, allograft and evolution (subsidence, resorption and remodelling). The Harris Hip score was used for clinical assessment.

Cryoprotectant permeation through human articular cartilage.

Objective: The cryopreservation of intact articular cartilage is constrained by minimal chondrocyte survival. It was the aim of the present study to gain an insight into the permeation kinetics of cryoprotectants through cartilage. This knowledge is essential for achieving adequate tissue permeation prior to cooling.

Peripheral primitive neuroectodermal tumor after radiotherapy.

A 41-year-old man had a peripheral neuroectodermal tumor develop at the distal third of the fibula 4 years after radiotherapy for relapsed villonodular synovitis. This type of sarcoma usually is classified into the heterogeneic group of small round-cell bone tumors as a subdivision of Ewing's sarcomas. The immuno-staining positivity of the neoplastic cells for the neuron-specific enolase allowed the authors to make the diagnosis of a tumor with neuroectodermal origin.