Relating the results of our investigations to the knowledge hitherto acquired about the etiology of osteoporosis (which I have already referred to), I am inclined to interpret the pathogenesis of osteoporosis in the following way: 1) Primary osteoblastic deficiency: congenital (Lobstein); involutive (senile osteoporosis?); 2) Reduced osteoblastic activity from absence of trophic stimuli: (inactivity, ovarian agenesia, eunuchoidism, menopause); 3) Reduced osteoblastic activity from inhibitory stimuli: (cortisone, adrenocorticotrophic hormone (A.C.T.H.), stress, Cushing's disease, thyrotoxicosis); 4) Normal osteoblastic activity but insufficiency of constructive material: (malnutrition, disturbances of the digestive system, insufficiency of vitamin C, diabetes, thyrotoxicosis, cortisone, A.C.T.H., stress, Cushing's disease). Osteoporosis may therefore be the consequence either of a congenital osteoblastic deficiency, such as that found in cases of osteogenesis imperfecta, or of reduced osteoblastic activity due to absence of trophic stimuli such as mechanical stress and the sex hormones, or of reduced activity of the bone cells due to anti-anabolic substances which inhibit them, such as cortisone and its derivatives and the thyroid hormone in strong doses, or lastly of reduced availability of construction material due to its introduction in reduced quantities (starvation, dysfunction of the digestive system) or due to hindering of synthesis (deficiency of vitamin C, diabetes, cortisone and its derivatives) or due to an excessive degree of destruction (thyrotoxicosis). In the case of anti-anabolic hormones from the adrenal cortex, the mechanism may thus be twofold: inhibition of the osteoblasts and deprivation of the osteoblasts of glucoprotein material due to a general anomaly of metabolism. This may perhaps explain the most serious forms of bone atrophy which are usually observable in cases of hyperfunction of the adrenal cortex. Senile osteoporosis should, in my opinion, be included in the first of our groups because it cannot be said to be brought about by any of the causes usually cited for osteoporosis– such as deficiency of sex hormones, excess of hormones from the adrenal cortex, deficiency of calcium, etc.–and in all probability it will depend on a progressive involution of the osteoblasts brought about by old age. Senile involution is an expression of the descending phase of life's parabola and it involves all the organs and all the parenchymatous tissues in the human body, but it does not cause a parallel reduction of functions and activities on all of them equally. The skeletal system is one of the first to feel these reductions, because in old age life necessarily becomes less intense. Consequently in the economy of the ageing subject the generally reduced level of metabolism brings about a sort of selection in the nourishment of the different organs and systems, and sometimes almost a dismantling of some of these in an attempt to fall in with the new and reduced level of activities of some of the parenchymatous tissues, activities which may be incomplete or even transferred elsewhere. We believe that the moment which originally determines the beginning of senile osteoporosis coincides with the involutional process of cellular metabolism that strikes at all parenchymatous tissue during old age–striking, in the case of osteoporosis, hardest of all at the bony tissues. There is, indeed, no doubt that certain essential processes of cellular metabolism do alter with age, and that the reduction in the activity of the gonads does have considerable importance. In any case, just as adolescence and old age cannot be explained only in terms of gonadal activity, so the involution of the skeleton cannot be due merely to the involution of the gonads. How should one then interpret the well known benefit afforded by administration of sex hormones in cases of osteoporosis? Probably the action of oestrogens and androgens is, in this case, of a pharmacological nature, and comparable, for instance, to the action of digitalis on the cardiac muscle. It will be remembered how digitalis acts almost exclusively on myofibrils which have become inadequate, and has little or no effect on a normal myocardium. Similarly, the sex hormones would seem to exert a stimulating action on osteoblasts that are on the way to involution, while they exert little or no action on normal osteoblasts. In support of this we have the findings of Urist and other workers, who demonstrated that the administration of sex hormones produces calcium and nitrogen retention only in osteoporotics, while in non-osteoporotic subjects of the same age it produces no effect. On the other hand, the action of the sex hormones might act in cases of senile osteoporosis by returning the changed level of protein metabolism to normal. From the data in the literature and from the results of our own investigations, I conclude that osteoporosis in general, and senile osteoporosis in particular, are first and foremost the result of a disturbance in the metabolism of bone, and that the metabolic disturbance is closely and exclusively related to the degree of activity and the state of activity of the cells in the bone. Lastly, I believe that senile osteoporosis should not be considered an actual disease but rather as one limited aspect of the normal descending parabola which affects to a greater or less degree all the tissues of the body

Objectives

The exact aetiology and pathogenesis of microdamage-induced long bone fractures remain unknown. These fractures are likely to be the result of inadequate bone remodelling in response to damage. This study aims to identify an association of osteocyte apoptosis, the presence of osteocytic osteolysis, and any alterations in sclerostin expression with a fracture of the third metacarpal (Mc-III) bone of Thoroughbred racehorses.

Objectives

Posterior condylar offset (PCO) and posterior tibial slope (PTS) are critical factors in total knee arthroplasty (TKA). A computational simulation was performed to evaluate the biomechanical effect of PCO and PTS on cruciate retaining TKA.

Objectives

Oxidative stress plays a major role in the onset and progression of involutional osteoporosis. However, classical antioxidants fail to restore osteoblast function. Interestingly, the bone anabolism of parathyroid hormone (PTH) has been shown to be associated with its ability to counteract oxidative stress in osteoblasts. The PTH counterpart in bone, which is the PTH-related protein (PTHrP), displays osteogenic actions through both its N-terminal PTH-like region and the C-terminal domain.

Aims

The number of patients undergoing arthroscopic surgery of the hip has increased significantly during the past decade. It has now become an established technique for the treatment of many intra- and extra-articular conditions affecting the hip. However, it has a steep learning curve and is not without the risk of complications. The purpose of this systematic review was to determine the prevalence of complications during and following this procedure.

Aims

Intercalary allografts following resection of a primary diaphyseal tumour have high rates of complications and failures. At our institution intercalary allografts are augmented with intramedullary cement and fixed using compression plating. Our aim was to evaluate their long-term outcomes.

‘Big data’ is a term for data sets that are so large or complex that traditional data processing applications are inadequate. Billions of dollars have been spent on attempts to build predictive tools from large sets of poorly controlled healthcare metadata. Companies often sell reports at a physician or facility level based on various flawed data sources, and comparative websites of ‘publicly reported data’ purport to educate the public. Physicians should be aware of concerns and pitfalls seen in such data definitions, data clarity, data relevance, data sources and data cleaning when evaluating analytic reports from metadata in health care.

Cite this article: Bone Joint J 2017;99-B:1571–6.

Objectives

Osteoporosis is a chronic disease. The aim of this study was to identify key genes in osteoporosis.

Aims

Manipulation under anaesthetic (MUA) is a recognised form of treatment for patients with a frozen shoulder. However, not all patients benefit. Some have persistent or recurrent symptoms. There are no clear recommendations in the literature on the optimal management of recurrent frozen shoulder after a MUA. We aimed to address this issue in this study.

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.

Episodic, or bundled payments, is a concept now familiar to most in the healthcare arena, but the models are often misunderstood. Under a traditional fee-for-service model, each provider bills separately for their services which creates financial incentives to maximise volumes. Under a bundled payment, a single entity, often referred to as a convener (maybe the hospital, the physician group, or a third party) assumes the risk through a payer contract for all services provided within a defined episode of care, and receives a single (bundled) payment for all services provided for that episode. The time frame around the intervention is variable, but defined in advance, as are included and excluded costs. Timing of the actual payment in a bundle may either be before the episode occurs (prospective payment model), or after the end of the episode through a reconciliation (retrospective payment model). In either case, the defined costs over the defined time frame are borne by the convener.

Cite this article: Bone Joint J 2017;99-B:1280–5.

Aims

To analyse the influence of upper extremity trauma on the long-term outcome of polytraumatised patients.

Aims

To determine whether there is any association between glomerular filtration rate (GFR) and blood cobalt (Co) and chromium (Cr) levels in patients with metal-on-metal (MoM) hip arthroplasty.