Introduction and Objective. Pectus carinatum is a common congenital anterior chest wall deformity, characterized by outward protrusion of sternum and ribcage resulted from rib cartilage overgrowth. The protrusion may be symmetrical or asymmetrical. Pectus carinatum association with mitral valve diseases, Marfan's syndrome, and scoliosis enforces that poor connective tissue development as possible etiological factor. Despite the coexistence of pectus carinatum and scoliosis has attracted the attention of some researchers, the association between pectus carinatum and the other spinal deformities has not been studied comprehensively. The frequency of spinal deformity in patients with pectus carinatum and the mutual relationships of their subtypes are needed to be studied to determine the epidemiological character of the combined deformity and to plan patient evaluation and management. Our study aimed to investigate the association, define the incidence and evaluate the characteristics between different types of spinal deformities and Pectus carinatum. Materials and Methods. Radiological and physical examinations were performed for 117 pectus carinatum patients in Marmara university hospital/Turkey in the years between 2006 and 2013. The incidence of spinal deformity was calculated. Spinal deformities were classified as scoliosis, kyphosis, kyphoscoliosis, and spinal asymmetry, whereas pectus carinatum were subdivided into symmetric and asymmetric subgroups. The relationship between spinal deformities and the symmetrical-asymmetric subtype of pectus excavatum was statistically analyzed, Pearson chi-square test was used to compare the association of qualitative data. The significance level was accepted as p <0.05. Lastly, the angular values of the deformities of scoliosis and kyphosis patients were measured using the Cobb method. In this way, the magnitude of the deformity was given as a numerical value. Results. Spinal deformity was detected in 23 (17 symmetrical PE and 6 asymmetrical PE) of 117 pectus excavatum patients. Scoliosis and kyphosis were seen equally in symmetrical pectus carinatum, whereas scoliosis was seen in 33.3% and kyphosis in 50% in asymmetric pectus carinatum patients, respectively. However, there were no statistically significant differences in the distribution of scoliosis and kyphosis in patients with symmetrical and asymmetrical PE. Idiopathic scoliosis constituted the most common scoliosis group. Congenital kyphosis was not found in any kyphosis patient. The average Cobb angle of scoliosis patients was 32°, and the mean T2-T12 kyphosis angle of these patients was 55.5°, while the average kyphosis angle of those with kyphosis deformity was 71°. Conclusions. Patients with Pectus carinatum have a higher incidence of spinal deformities than the normal population. Such high concomitant incidence should be taken under consideration in evaluating and treating patients presenting with either deformity

Dysplasia Epiphysealis Hemimelica (DEH) also known as Trevor's Disease is a rare developmental disorder resulting in cartilaginous overgrowth of the epiphysis of long bones. DEH is usually diagnosed in children between two and eight years old and it is three times more often diagnosed in boys. The most reported complaints are pain, limitation in range of motion, and deformity or swelling of the affected joint. Treatment of symptomatic lesions consists of surgical resection of the lesion, resulting in good long-term results. Based on histological evaluation, DEH is often described as an osteochondroma or an osteochondroma-like lesion, although there are clinical, radiological and genetic differences between DEH and osteochondromas. To investigate the hypothesis that DEH and osteochondromas are histologically identical, two cases of DEH and two cases of osteochondromas in patients with Hereditary Multiple Osteochondroma (HMO) are compared at histological level. Tissue samples from patients with a histopathologically confirmed diagnosis of DEH were compared with two age and gender matched patients diagnosed with HMO. After tissue sampling and processing, (immuno)histological stainings were performed for Collagen type II, Collagen type X, Sox-9 and Safranin-O. Histologically, clumping of chondrocytes in a fibrillar matrix, a thick disorganized cartilage cap and ossification centres with small amounts of unresorbed cartilage were observed in DEH. In contrast, chondrocyte organisation in cartilage of osteochondromas displays characteristics of the normal growth plate. In addition, differences in expression of collagen type II, collagen type X and Sox9 were observed. Collagen type II was expressed in the extracellular matrix surrounding proliferative and hypertrophic chondrocytes in osteochondromas, while weak expression was observed in the entire cartilage cap in DEH. Collagen type X was not expressed in DEH, while expressed in the pericellular matrix surrounding hypertrophic chondrocytes in osteochondromas. Staining for Sox9 was positive in the hypertrophic chondrocytes in osteochondromas, while expressed in the nuclei of all chondrocyte clusters in DEH. Both morphological and immunohistological differences were observed in histological sections of DEH and osteochondromas. These findings reject our hypothesis, and supports the earlier observed clinical, radiological and genetic differences and implies a different aetiology between DEH and osteochondroma formation in HMO

Introduction. Skeletal abnormalities caused by disproportioned bone overgrowth (LBO), are a common trait in Marfan syndrome (MFS), a connective tissue disease caused by mutations in the extracellular matrix (ECM) protein and TGFβ regulator fibrillin-1 (Fbn1). The cause of LBO in MFS is unknown and therapies are not available. Fibrillin-1 hypomorphic mouse model (Fbn1mgR/mgR) faithfully replicates MFS skeletal manifestations including elongated bones however, its early demise due aortic rupture limit the magnitude of LBO investigation. Materials and Methods. To circumvent Fbn1mgR/mgR lethality and investigate the contribution of specific skeletal tissues to LBO, Fbn1 gene expression was targeted in developing limbs by crossing Fbn1Lox/Lox mice with Prx1-Cre, in or bone with Osx-Cre, in cartilage and perichondrium with Col2-Cre, in skeletal muscles with Mef2c-Cre, and ligaments and tendons with Scx-Cre. Bones length of Fbn1 conditional mice KO was measured and relevant histological, cellular and biomechanical parameters were assessed. Results. Fbn1Prx1−/+ and Fbn1Prx1−/− mice had longer limbs bones compared to WT mice and amount of fibrillin-1 in the limb matrix was inversely proportional to bone length. Interestingly, Fbn1 gene targeting in ligaments/tendons resulted in LBO, altered tissues' mechanics and TGFβ-induced switch of tendon stem cells to chondrocytes. Gene targeting in other limb's anatomical locations did not result in LBO thus ruling out the participation of surrounding tissues to this bone phenotype. Discussion. Fbn1 gene inactivation in ligament/tendon is associated with increased local TGFβ, altered biomechanical properties and LBO. As previously reported, ligaments/tendons respond to changes in mechanical load by increasing the levels and/or the activity of TGF-β while bones undergo morphological adaptation in response to muscle loads transmitted by tendons. We hypothesize that dysregulation of local TGFβ signaling and altered biomechanical properties of fibrillin-1 deficient ligaments/tendons affect endochondral ossification by improper load transmission to bone. By showing ligament/tendon-dependent regulation of postnatal longitudinal bone growth this study provides a paradigm-shift in tendon biology and it shades a new light on LBO pathophysiology in MFS, thus providing the bases for new pharmacological interventions for this and related skeletal conditions

Summary Statement. It is now possible to diagnose osteoporosis using incidental CT scans; this approach has been used to objectively demonstrate the role of osteoporosis in fracture in ankylosing spondylitis patients. Background. In advanced disease, Ankylosing Spondylitis (AS) is frequently associated with a reduction in bone mineral density (BMD), this contributes to pain and predisposes to fractures. Quantifying this reduction in BMD is complicated by the simultaneous processes occurring, in which there is both an overgrowth of bone (syndesmophytes) and a concurrent loss of trabecular bone. Traditional methods such as dual-energy X-ray absorptiometry (DXA) struggle to generate accurate estimates for BMD in these patients. It has recently become possible to diagnose osteoporosis, with a high sensitivity and specificity, using incidental CT scans of the L1 vertebra. The purpose of this study was to evaluate the use of opportunistic CT screening in the diagnosis of osteoporosis in patients with AS who had sustained vertebral fractures. Patients & Methods. Following Institutional review board approval, patients with AS who presented, with acute fractures of the spine, to our facility between 2004 and 2013 were reviewed to assess whether or not they had a Computed Tomography (CT) scan of the abdomen on admission or in the 6 months before or after injury. In addition, patients were also required to have signs of advanced AS such as the presence of syndesmophytes and syndesmophyte bridging; patients with fractures through L1 were excluded. Of those fitting the criteria, a region of Interest (ROI) was generated over the body of L1, Hounsfield unit (HU) were then measured. Results. Of the 42 patients reviewed, a total of 17 AS patients fit the above criteria. 15 were male and 2 were female, mean age of the whole cohort was 69.9years (range 22–85; SD 15.9). Using a threshold balanced for sensitivity and specificity (<135 HU) which differentiates between osteopenia and osteporosis, 14 (82%) patients were found to have a BMD less than 135HU; a higher threshold (<160 HU) with 90 % sensitivity for differentiating osteoporosis from osteopenia was applied to the group, and 15 patients (88%) were found to be osteoporotic. Of note all the females in the study were osteoporotic. Discussion and Conclusion. This study demonstrates, for the first time, using opportunistic CT screening, that a high proportion of AS patients who sustain fractures have osteoporosis; this overcomes the difficulties that have been encountered with the use of DXA in this unique group of patients. This simple and accessible method saves on excess cost and exposure to radiation. With a high sensitivity, patients identified using this method can then be managed more proactively. We believe these data have the potential to significantly impact the day to day management of patients with spondyloarthropathies

Objectives

Implant-related infection is one of the most devastating complications in orthopaedic surgery. Many surface and/or material modifications have been developed in order to minimise this problem; however, most of the in vitro studies did not evaluate bacterial adhesion in the presence of eukaryotic cells, as stated by the ‘race for the surface’ theory. Moreover, the adherence of numerous clinical strains with different initial concentrations has not been studied.

Objectives

The present study describes a novel technique for revitalising allogenic intrasynovial tendons by combining cell-based therapy and mechanical stimulation in an ex vivo canine model.

Intermittently administered parathyroid hormone (PTH 1-34) has been shown to promote bone formation in both human and animal studies. The hormone and its analogues stimulate both bone formation and resorption, and as such at low doses are now in clinical use for the treatment of severe osteoporosis. By varying the duration of exposure, parathyroid hormone can modulate genes leading to increased bone formation within a so-called ‘anabolic window’. The osteogenic mechanisms involved are multiple, affecting the stimulation of osteoprogenitor cells, osteoblasts, osteocytes and the stem cell niche, and ultimately leading to increased osteoblast activation, reduced osteoblast apoptosis, upregulation of Wnt/β-catenin signalling, increased stem cell mobilisation, and mediation of the RANKL/OPG pathway. Ongoing investigation into their effect on bone formation through ‘coupled’ and ‘uncoupled’ mechanisms further underlines the impact of intermittent PTH on both cortical and cancellous bone. Given the principally catabolic actions of continuous PTH, this article reviews the skeletal actions of intermittent PTH 1-34 and the mechanisms underlying its effect.

Cite this article: L. Osagie-Clouard, A. Sanghani, M. Coathup, T. Briggs, M. Bostrom, G. Blunn. Parathyroid hormone 1-34 and skeletal anabolic action: The use of parathyroid hormone in bone formation. Bone Joint Res 2017;6:14–21. DOI: 10.1302/2046-3758.61.BJR-2016-0085.R1.

Objectives

We sought to determine if a durable bilayer implant composed of trabecular metal with autologous periosteum on top would be suitable to reconstitute large osteochondral defects. This design would allow for secure implant fixation, subsequent integration and remodeling.

Objectives

An experimental piglet model induces avascular necrosis (AVN) and deformation of the femoral head but its secondary effects on the developing acetabulum have not been studied. The aim of this study was to assess the development of secondary acetabular deformation following femoral head ischemia.

We investigated the effect of stimulation with a pulsed electromagnetic field on the osseointegration of hydroxyapatite in cortical bone in rabbits. Implants were inserted into femoral cortical bone and were stimulated for six hours per day for three weeks.

Electromagnetic stimulation improved osseointegration of hydroxyapatite compared with animals which did not receive this treatment in terms of direct contact with the bone, the maturity of the bone and mechanical fixation. The highest values of maximum push-out force (F_max) and ultimate shear strength (σ_u) were observed in the treated group and differed significantly from those of the control group at three weeks (F_max; p < 0.0001; σ_u, p < 0.0005).

Ovine articular chondrocytes were isolated from cartilage biopsy and culture expanded in vitro. Approximately 30 million cells per ml of cultured chondrocytes were incorporated with autologous plasma-derived fibrin to form a three-dimensional construct. Full-thickness punch hole defects were created in the lateral and medial femoral condyles. The defects were implanted with either an autologous ‘chondrocyte-fibrin’ construct (ACFC), autologous chondrocytes (ACI) or fibrin blanks (AF) as controls. Animals were killed after 12 weeks. The gross appearance of the treated defects was inspected and photographed. The repaired tissues were studied histologically and by scanning electron microscopy analysis.

All defects were assessed using the International Cartilage Repair Society (ICRS) classification. Those treated with ACFC, ACI and AF exhibited median scores which correspond to a nearly-normal appearance. On the basis of the modified O’Driscoll histological scoring scale, ACFC implantation significantly enhanced cartilage repair compared to ACI and AF. Using scanning electron microscopy, ACFC and ACI showed characteristic organisation of chondrocytes and matrices, which were relatively similar to the surrounding adjacent cartilage.

Implantation of ACFC resulted in superior hyaline-like cartilage regeneration when compared with ACI. If this result is applicable to humans, a better outcome would be obtained than by using conventional ACI.