Traumatic brain injury enhances the formation of heterotopic ossification around the hip : an animal model study

Introduction: The incidence of heterotopic ossification (HO) is at its highest when trauma of the hip or pelvis concurs with traumatic brain injury (TBI). The pathogenic mechanisms underlying the neurogenic enhancement of the formation of HO remain, however, poorly understood. Hence, the goal of the present study was to develop a novel small animal model that combines hip and brain trauma that can prove the enhancement of HO around the hip after TBI. Materials and methods: Forty male Wistar rats were divided into four groups, to undergo hip surgery alone (group 1), hip surgery + moderate TBI (group 2), hip surgery + severe TBI (group 3) and only severe TBI (group 4). The femoral canal was reamed up to 2 mm and a muscle lesion was made to simulate hip surgery. An established controlled cortical impact model was used to create a TBI. Twelve weeks after surgery, the hip with the proximal half of the femur and the pelvic bone was removed and subjected to micro-computed tomography (µCT) analysis. A quantitative analysis using a modified Brooker score as well as a quantitative analysis using a bone-to-tissue ratio was used. Results: No HO could be found in all the ten animals that did not undergo hip surgery (group 4). In the animals that did undergo surgery to the hip, no HO was found in only one animal (group 1). All the other animals developed HO. In this study, significantly more HO was found in animals that underwent an additional severe TBI. Conclusion: The newly developed rat model, with a combined hip and brain trauma, showed an enhancement of the HO formation around the hip after severe TBI

Conventional versus direct magnetic resonance imaging in detecting labral lesions in femoroacetabular impingment - a retrospective multicenter study.

The purpose of this study was to assess the reliability of Direct Magnetic Resonance Arthography (MRA) and Conventional Magnetic Resonance Imaging (MRI) in diagnosing labral lesions in patients with symptoms of femoroacetabular impingement (FAI). Materials and methods: Imaging and surgical data (n=490) were retrospectively collected from 5 high-volume centres providing arthroscopic treatment of FAI patients. Preoperative magnetic resonance imaging findings were compared with the actual surgical findings regarding labral condition in order to assess the effectiveness of MRI and MRA in identifying the presence of labral tears in patients with FAI. The results of this study indicate that MM and MRA may both be useful for the diagnosis of acetabular labral lesions. The accuracy is slightly higher for MRI (71,4 %) compared to MRA (68,2 %), although MRA has higher sensitivity (74.4%,) as compared to MRI (66,9%). Conclusions: In a clinically suspected labral tear MRA has higher sensitivity than MRI. Further studies on asymptomatic patients may be needed to determine the specificity of different MRI techniques

Махмуд се готви...

ДВД, посветено на традиционалната музичка и играорна култура на Македонците муслимани

The pathogenesis of heterotopic ossification after traumatic brain injury. A review of current literature.

Introduction: Neurogenic heterotopic ossification (NHO), mostly defined as a benign process of formation of bone outside the skeletal system, after traumatic brain injury (TBI) is a musculoskeletal disorder that causes pain and reduces the range of motion, often leading to marked impairment of quality of life. The pathogenic factors that link the brain and bone and cause the formation of heterotopic bone are largely unknown. This article will try to summarize the current literature on the pathogenesis of NHO and accelerated fracture healing after TBI.Pathogenesis: The heterotopic formation of bone after TBI seems to be inducted by a complex interplay between local and systemic factors. For all different forms of HO, the same three conditions are required for the formation of ectopic bone: The presence of osteoprogenitor cells, a permissive environment, and a stimulating factor. The osteoprogenitor cells are thought to be of mesenchymal origin, however recent research suggests a possible neural origin. The permissive environment is created mainly by reactions to hypoxia and both local and sensory nerve inflammation. Many possible inducing factors have been described; the endogenic route is thought to be the most dominant in the stimulation of HO formation after TBI

The diagnostic value of SE MRI and DWI of the spine in patients with monoclonal gammopathy of undetermined significance, smouldering myeloma and multiple myeloma

Objectives: To evaluate DWI of the bone marrow in the differentiation of monoclonal gammopathy of undetermined significance (MGUS), smouldering myeloma (SMM) and multiple myeloma (MM). Methods The retrospective study includes 64 patients with MGUS, 27 with SMM, 64 with new MM and 12 controls. Signal intensity (SI) of spinal SE-MRI and DWI (b0-1000) as well as apparent diffusion coefficients (ADC) were measured in the T10 and L3. Qualitative assessment of b-images was performed by one experienced radiologist. Results: ADC600 and ADC1000 are the best ADC values in differentiating patient groups (p50 % (p=0.001). Only SIT2 for L3 can differentiate MGUS from SMM (p=0.044) and PC%0-10 from PC%10-25 (p=0.033). Qualitative interpretation of b1000 images allows differentiating MM patients from those with MGUS or SMM (p<0.001). Conclusions: Spinal SE-MRI can differentiate among MGUS, SMM, MM and control subjects. DWI based on the SI on b1000 images and ADC values is increased in MM compared to MGUS and SMM. Qualitative assessment of b-images can differentiate MM from MGUS or SMM. Key points: - ADC values are higher in patients with MM compared to MGUS - DWI parameters change late in disease evolution - DWI is sensitive but not specific in diagnosing patients with MM - Qualitative DWI assessment is good in detecting myeloma patient

Bilateral Pseudarthrosis of the Femoral Neck in a 25-Year-Old Male with Hereditary Hypophosphatemic Rickets

Hereditary hypophosphatemic rickets (HHR) is a rare disorder of renal phosphate wasting and the most common form of heritable rickets. Here, we report a case of an active 25-year-old male with HHR showing atraumatic bilateral femoral neck pseudarthrosis after 4 years of consecutive knee pain. A conservative therapy was administered, taking into account both the risks of surgical treatment and the little impairment even in the sport activities which the patient experienced

Conventional versus direct magnetic resonance imaging in detecting labral lesions in femoroacetabular impingment - a retrospective multicenter study

The purpose of this study was to assess the reliability of Direct Magnetic Resonance Arthography (MRA) and Conventional Magnetic Resonance Imaging (MRI) in diagnosing labral lesions in patients with symptoms of femoroacetabular impingement (FAI).Materials and methods: Imaging and surgical data (n=490) were retrospectively collected from 5 high-volume centres providing arthroscopic treatment of FAI patients. Preoperative magnetic resonance imaging findings were compared with the actual surgical findings regarding labral condition in order to assess the effectiveness of MRI and MRA in identifying the presence of labral tears in patients with FAI.The results of this study indicate that MRI and MRA may both be useful for the diagnosis of acetabular labral lesions. The accuracy is slightly higher for MRI (71,4 %) compared to MRA (68,2 %), although MRA has higher sensitivity (74.4%,) as compared to MRI (66,9%).Conclusions: In a clinically suspected labral tear MRA has higher sensitivity than MRI. Further studies on asymptomatic patients may be needed to determine the specificity of different MRI techniques

De rol van musculair trauma in het ontstaan van heterotope ossificatie na heupchirurgie: studie aan de hand van een dierenmodel in ratten /

Master of Medicine in de specialistische geneeskunde: orthopedische heelkund

Surface Functionalization of Orthopedic Titanium Implants with Bone Sialoprotein

Orthopedic implant failure due to aseptic loosening and mechanical instability remains a major problem in total joint replacement. Improving osseointegration at the bone-implant interface may reduce micromotion and loosening. Bone sialoprotein (BSP) has been shown to enhance bone formation when coated onto titanium femoral implants and in rat calvarial defect models. However, the most appropriate method of BSP coating, the necessary level of BSP coating, and the effect of BSP coating on cell behavior remain largely unknown. In this study, BSP was covalently coupled to titanium surfaces via an aminosilane linker (APTES), and its properties were compared to BSP applied to titanium via physisorption and untreated titanium. Cell functions were examined using primary human osteoblasts (hOBs) and L929 mouse fibroblasts. Gene expression of specific bone turnover markers at the RNA level was detected at different intervals. Cell adhesion to titanium surfaces treated with BSP via physisorption was not significantly different from that of untreated titanium at any time point, whereas BSP application via covalent coupling caused reduced cell adhesion during the first few hours in culture. Cell migration was increased on titanium disks that were treated with higher concentrations of BSP solution, independent of the coating method. During the early phases of hOB proliferation, a suppressive effect of BSP was observed independent of its concentration, particularly when BSP was applied to the titanium surface via physisorption. Although alkaline phosphatase activity was reduced in the BSP-coated titanium groups after 4 days in culture, increased calcium deposition was observed after 21 days. In particular, the gene expression level of RUNX2 was upregulated by BSP. The increase in calcium deposition and the stimulation of cell differentiation induced by BSP highlight its potential as a surface modifier that could enhance the osseointegration of orthopedic implants. Both physisorption and covalent coupling of BSP are similarly effective, feasible methods, although a higher BSP concentration is recommended