Use of oral bisphosphonates and the risk of aseptic osteonecrosis: a nested case-control study

OBJECTIVE

To determine whether use of oral bisphosphonates is associated with an increased risk of aseptic osteonecrosis (AON) among a cohort of elderly cardiovascular patients.

METHODS

We conducted a nested case-control study within a previously defined cardiovascular cohort of elderly Quebec patients using linked administrative health databases. Cases were defined as those with the diagnosis of hospitalization secondary to AON at a nonspecified site. For each case, 10 controls were randomly selected and matched to the cases by age, calendar time, and length of followup. The main outcome measure was the risk ratio (RR) of AON among ever-users of oral bisphosphonates compared to that among nonusers. As a quality measure, RR for AON among users of statin and angiotensin-converting enzyme inhibitors (ACE-I) compared to nonusers were also calculated.

RESULTS

The initial cohort consisted of 87,837 subjects. In the primary analysis, the adjusted RR for AON among bisphosphonate users was 2.87 (95% CI 1.71-5.05). The adjusted RR for alendronate, etidronate, and risedronate were 2.87 (95% CI 1.46-5.67), 2.43 (95% CI 1.05-5.62), and 3.34 (95% CI 1.04-10.67), respectively. There were no significant differences in RR for AON among current users (most recent drug exposure within 90 days of diagnosis) and past users (drug exposure between 91 and 365 days before diagnosis) of bisphosphonates. The adjusted RR for both statins and ACE-I were 0.79 (95% CI 0.49-1.07) and 1.16 (95% CI 0.79-1.70), respectively.

CONCLUSION

In this cohort of elderly cardiovascular patients, an association was observed between oral bisphosphonate use and aseptic osteonecrosis. Further research into this putative association is required.

The functional capacity of healthcare workers with history of severe acute respiratory distress syndrome (SARS) complicated with avascular necrosis--case report

Two years after the SARS outbreak in Hong Kong, 128 healthcare workers continued to present with musculoskeletal complaints and 38 workers were diagnosed with avascular necrosis (AVN) in different joints. 13 healthcare workers were referred to six designated Physiotherapy Departments of the Hospital Authority for a tailor-made standardized Functional Capacity Evaluation (FCE) from 2004 to 2005 on a voluntary basis. Job analysis, workers' self-perceived disability and functional capacity, non-material handling tests, and the cardiopulmonary fitness test were performed. Retrospective review of the FCE data showed that there were 17 AVN of hips, 16 AVN of knees, 3 AVN of shoulders. All patients had AVN of lower limb joints. Nearly full ranges of movement (ROM) were observed in the knees involved, but the hip range was decreased for most subjects suffering from hip AVNs. Most workers (n=12) could not complete the cardiopulmonary test due to intolerable joint pain. Six workers' self-perceived physical demands level (PDC) matched with the physical demands level identified by the FCE. 12 healthcare workers attained a sedentary physical demands level and were unable to match with their previous job demands. One staff was classified as light physical demands and managed his original duty. Four workers had returned to work at the time FCE was performed. The tailor-made FCE added information to facilitate the return-to-work planning for the staff. Four more workers returned to work with modified duties one year after the FCE.

Osteonecrosis of the jaws secondary to bisphosphonate therapy: a case series

AIM

The objective of this report is to present the clinical experiences of several patients affected with osteonecrosis (ONJ) secondary to bisphosphonate (BP) therapy and to provide a discussion of the specific BPs implicated in this condition.

BACKGROUND

ONJ secondary to BP therapy is becoming an increasingly reported complication following dental therapy. This is particularly true of surgical dental procedures such as extractions. BPs are a class of pharmaceuticals used in the treatment of numerous disorders affecting bone, including osteoporosis, cancer metastases to bone, hypercalcemia of malignancy, and multiple myeloma. Although ONJ is a more recently described phenomenon, it is an emerging problem that may be associated with significant morbidity such as oral dysfunction, impaired eating ability, pain, and compromised esthetics resulting in a poor quality of life in affected patients.

CASE REPORT

This is a description of 13 patients affected with ONJ secondary to BP therapy managed at the Orofacial Pain & Oral Medicine Center, Special Patients Clinic, and Oral and Maxillofacial Surgery Clinic at the University of Southern California, School of Dentistry between October 2005 and April 2007, with a discussion of the specific BPs implicated in this condition, the clinical presentation, management, and follow-up.

SUMMARY

Thorough reporting of every case of ONJ is important to help advance the understanding of this poorly understood condition. The authors' approach to care represents a more conservative mode to management than previously described by many investigators.

Shoulder arthroplasty for traumatic avascular necrosis: predictors of outcome

Posttraumatic avascular humeral head necrosis may require salvage shoulder arthroplasty in symptomatic cases. We tested the hypothesis that associated tuberosity malunion negatively influences the final clinical outcome after shoulder arthroplasty. Thirty-eight patients with posttraumatic avascular necrosis of the humeral head were followed clinically and radiographically for a minimum of 5 years (mean, 8 years; range, 5-13 years). To quantify preoperative tuberosity malunion, two novel radiographic parameters were introduced: on the anteroposterior view, the greater tuberosity offset as a measurement of lateralization of the greater tuberosity; and on the axillary view, the posterior offset to quantify the degree of widening at the intertubercular groove. At last followup, the average Constant and Murley score had improved from 27 points preoperatively to 57 points postoperatively; shoulder range of motion had increased from 40 degrees abduction to 116 degrees, flexion from 45 degrees to 120 degrees, and external rotation from 15 degrees to 39 degrees. Functional improvements and pain relief were substantial. A significant correlation was found between greater tuberosity offset and posterior offset and final clinical outcome. Preoperative near anatomic tuberosity alignment was associated with good results. The greater tuberosity offset and posterior offset are useful and reliable radiographic predictors of outcome.

Osteonecrosis of the hip: novel approaches to evaluation and treatment

The treatment of osteonecrosis of the hip remains a dilemma. Contemporary basic science research focuses on establishing the molecular etiology of this disease with the hope of identifying targets for pharmacologic intervention. Researchers have identified specific genetic polymorphisms that may predispose its development and these may allow early diagnosis and treatment of at-risk patients. Refinements in magnetic resonance imaging aid in the staging of patients with osteonecrosis and findings appear to correlate with clinical outcome. Novel nonoperative and operative modalities for the treatment of osteonecrosis are also under investigation. The results of new pharmacologic and biophysical treatments appear beneficial in delaying, and possibly preventing, the progression of precollapse lesions. New bone grafting strategies may enhance the results of core decompression. Although the results of conventional total hip arthroplasty have improved, newer surface replacement systems provide satisfactory short-term outcomes and may preserve bone stock in younger patients. Further research is needed to clarify the roles of these emerging technologies in the treatment of osteonecrosis of the hip. Until there is convincing evidence of efficacy in randomized clinical trials, we recommend appropriate staging and core decompression with or without bone graft for precollapse lesions and total hip arthroplasty or surface replacement for advanced disease.

Particle-induced osteolysis in three-dimensional micro-computed tomography

Small-animal models are useful for the in vivo study of particle-induced osteolysis, the most frequent cause of aseptic loosening after total joint replacement. Microstructural changes associated with particle-induced osteolysis have been extensively explored using two-dimensional (2D) techniques. However, relatively little is known regarding the 3D dynamic microstructure of particle-induced osteolysis. Therefore, we tested micro-computed tomography (micro-CT) as a novel tool for 3D analysis of wear debris-mediated osteolysis in a small-animal model of particle-induced osteolysis. The murine calvarial model based on polyethylene particles was utilized in 14 C57BL/J6 mice randomly divided into two groups. Group 1 received sham surgery, and group 2 was treated with polyethylene particles. We performed 3D micro-CT analysis and histological assessment. Various bone morphometric parameters were assessed. Regression was used to examine the relation between the results achieved by the two methods. Micro-CT analysis provides a fully automated means to quantify bone destruction in a mouse model of particle-induced osteolysis. This method revealed that the osteolytic lesions in calvaria in the experimental group were affected irregularly compared to the rather even distribution of osteolysis in the control group. This is an observation which would have been missed if histomorphometric analysis only had been performed, leading to false assessment of the actual situation. These irregularities seen by micro-CT analysis provide new insight into individual bone changes which might otherwise be overlooked by histological analysis and can be used as baseline information on which future studies can be designed.

Osteonecrosis in patients with human immunodeficiency virus type 1 infection in Taiwan

Osteonecrosis, a disabling complication associated with antiretroviral therapy (ART) and human immunodeficiency virus (HIV) infection, has rarely been reported in an Asian population. After an observation of 3,250 person-years (PY), 11 of 967 (1.1%) HIV-infected patients at a median age of 34 years developed osteonecrosis involving the hip joints (incidence, 3.4 per 1,000 PY). Their median CD4+ lymphocyte count had increased from 35 cells/microL at the diagnosis of HIV infection to 297 cells/microL at the diagnosis of osteonecrosis. The crude rate of osteonecrosis increased from 0% in patients without exposure to ART to 2.6 and 1.7% in patients with exposure to nucleoside reverse transcriptase inhibitors (NRTIs) and who had undergone highly active antiretroviral therapy (HAART) for 5 years or longer, respectively (P=0.18 and 0.09, respectively). Among the patients receiving HAART, the estimated incidence of osteonecrosis was 4.2 per 1,000 PY. Patients with osteonecrosis had a longer duration of exposure to NRTIs (1,641 versus 1,264 days, P=0.26) and to HAART (1,603 versus 1,251 days, P=0.42), a higher serum triglyceride (median, 1,130 versus 351 mg/dL; P=0.09), and a higher proportion of lipodystrophy (81.8 versus 15.0%, P<0.0001). Our report suggests that osteonecrosis is a rare complication in HIV-infected patients with prolonged exposure to ART with resultant metabolic complications.

Fractures and avascular necrosis before and after orthotopic liver transplantation: long-term follow-up and predictive factors

With early posttransplant bone loss, orthotopic liver transplantation (OLT) recipients experience a high rate of fracturing and some avascular necrosis (AVN), but little is known about the incidence of and predictive factors for these skeletal complications. We studied 360 consecutive patients who underwent transplantation for primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) and assessed both vertebral and nonvertebral (rib, pelvic, and femur) fractures in a protocolized fashion. Before OLT, 20% of the patients had experienced fracturing, and 1.4% of the patients had experienced AVN. Following OLT, there was a sharp increase in fracturing, with a 30% cumulative incidence of fractures at 1 year and 46% at 8 years after transplantation. In contrast to previous studies, there was a similar incidence of posttransplant vertebral and nonvertebral fractures. The greatest risk factors for posttransplant fracturing were pretransplant fracturing and the severity of osteopenia and posttransplant glucocorticoids. Nine percent of the liver recipients experienced AVN after OLT, and this correlated with pretransplant and posttransplant lipid metabolism, bone disease (bone mineral density and fracturing), and posttransplant glucocorticoids. A novel association between cholestasis and AVN was also identified, the mechanism for which is not known.

CONCLUSION

Fortunately, recent years have seen an increase in the bone mass of liver recipients and, along with this, less fracturing and less AVN. Nonetheless, 25% of patients undergoing OLT for chronic cholestatic liver disease still develop de novo fractures after OLT; this situation demands an ongoing search for effective therapeutic agents for these patients.

Bisphosphonates and osteonecrosis of the jaws: Science and rationale

Bisphosphonates as a group of drugs were introduced for the management of various conditions such as osteoporosis, Paget's disease, multiple myeloma, hypercalcemia of malignancy, breast cancer, prostate cancer, and other tumors. This group of drugs has improved the quality of life in many patients with proven efficacy in limiting pain and skeletal-related events. The controversy of osteonecrosis of the jaws and bisphosphonates is a recent and growing problem. Osteonecrosis of the jaws is recognized as a serious complication of bisphosphonate therapy, more commonly with the intravenous form of the drugs. However, there is limited scientific understanding about the association between osteonecrosis of the jaws and bisphosphonates. In the present article we discuss various mechanisms of action of bisphosphonates, the rationale for occurrence of osteonecrosis in the jaws, and treatment guidelines for the condition.

In vivo glenohumeral contact forces—Measurements in the first patient 7 months postoperatively

Knowledge of forces in the glenohumeral joint is essential for understanding normal and pathologic shoulder function. It forms the basis for performing fracture treatment or joint replacement surgery, for optimizing implant design and fixation and for improving and verifying analytical biomechanical models of the shoulder. An instrumented shoulder implant with telemetric data transmission was developed to measure six components of joint contact forces and moments. A patient with humeral head arthrosis achieved good joint function after its implantation. During the first 7 postoperative months, the contact force remained below 100% BW (percent body weight) for most activities of daily living. It ranged up to 130% BW for arm positions close to the limits of motion or when acting against external resistance. When the patient tried to turn a blocked steering wheel with maximum effort, the force rose to about 150% BW, the highest level observed thus far. Of great interest were the force directions relative to the humerus, especially those in the sagittal plane, which were not greatly influenced by the type of exercise, the arm position or the external resistance. The moments due to friction in the joint reached 5.2 Nm. The friction-induced shift of contact forces relative to the implant head centre ranged up to 6.3mm. These first worldwide in vivo measurements of glenohumeral contact forces are being continued in more patients and for longer postoperative times.

The pathogenesis of osteonecrosis

Although numerous studies concerning the pathogenesis of osteonecrosis have been published, the pathophysiologic mechanisms that may be involved continue to be debated. In the early 1980s, the concept of accumulative cell stress was advanced, which is a theory that proposes that bone cells are exposed to multiple insults or stresses, the effects of which accumulate to the point that the cells cannot sustain themselves and die. Technologic advances have led scientists to a better understanding of cell and molecular biology, and recent studies of osteonecrosis and its risk factors have indicated that this concept should be revisited. It now appears that using the term "necrosis" may be incorrect and that apoptosis may play a significant role. Research on osteoporosis, fracture healing, bone graft incorporation, hematology, and genetics may lend insight into the etiology and pathogenesis of osteonecrosis. Several studies on osteoporosis have focused on the effect of exogenous glucocorticoids on the behavior of osteocytes, osteoblasts, osteocytes, and their precursors. Recent findings on osteonecrosis and bone biology are placed into the context of what has been previously reported.

Therapy Insight: osteoporosis and osteonecrosis in systemic lupus erythematosus

Survival of patients with systemic lupus erythematosus (SLE) has improved over the past decade, thanks to improved treatment of the disease, which now results in fewer fatal complications. This improvement has allowed physicians to focus their attention on the prevention of organ damage caused by this chronic, inflammatory disease, and by the medications used to control the disease. Osteoporosis is common in SLE patients; risk factors for osteoporosis include prolonged use of glucocorticoids, cyclophosphamide and possibly gonadotropin-releasing-hormone agonists. In premenopausal women with SLE, inflammation or SLE-related medications can increase bone turnover, which eventually weakens bone architecture, then reduces bone strength and increases the risk of fracture. Prevention and treatment of osteoporosis in SLE patients should entail a multifaceted approach. Levels of calcium, vitamin D and homocysteine should be evaluated, and age-appropriate supplementation instituted. The bone loss that results from systemic inflammation should be treated by reduction of the inflammation with glucocorticoids, potent anti-inflammatory agents or antiresorptive agents. The efficacy of this therapy can be monitored using bone mineral density scans. This Review briefly discusses the pathophysiology of the localized and generalized osteoporosis and osteonecrosis in SLE patients and recommends therapies to both prevent and treat these unfortunate complications of this disease.

Vascularized Capitate Transposition for Advanced Kienb??ck Disease

Based on anatomic study, the vascularized capitate transposition to replace excised necrotic lunate was designed and applied in 40 cases of advanced Kienböck disease. It includes excision of the necrotic lunate and proximal shift of the vascularized capitate. The blood supply of the transposed capitate is provided by the dorsal branch of the anterior interosseous artery. Bone union occurred radiographically, and no postoperative capitate necrosis occurred in all cases after 6 weeks. Twenty-three cases were followed up for 1 year. No residual wrist pain existed in the range of motion, but limited residual wrist pain existed in labor work. The arc of motion ranged on average from 35 degrees of flexion to 45 degrees of extension. The grip power of the affected hand reached on average 70% compared with the contralateral. The authors conclude the vascularized capitate transposition is a reliable alternative for advanced Kienböck disease.

Osteonecrosis of the jaw and bisphosphonates--putting the risk in perspective

Osteonecrosis of the jaw is a poorly understood condition that has recently been associated with the use of potent bisphosphonate treatment. The prevalence appears to be approximately 1-10% in patients with malignancy treated with very high doses of intravenous bisphosphonates. In Paget's disease and osteoporosis, where the doses of bisphosphonate used are an order of magnitude lower than the oncology dose, the prevalence appears to be much lower--probably less than 1 in 60,000. The aim of this article is to put the risks of osteonecrosis of the jaw into context with the benefits of bisphosphonate treatment in these clinical scenarios.

The physiology of bone blood flow: a review

INTRODUCTION

Bone circulation plays an important role in bone physiology, but has been relatively poorly studied, because most techniques of circulatory research are difficult to apply to bone. This article summarizes briefly some of the important aspects of the physiology of bone blood flow most relevant to orthopaedics.

METHODS

The gold standard for experimental measurement of bone blood flow is the radioactive microsphere technique, though advances are being made in other techniques, such as positron emission tomography, laser and ultra-sound Doppler velocimetry, and near infrared spectroscopy, that may provide useful clinical measurement in the future.

RESULTS

Multiple vascular pathways contribute to an adaptive response to traumatic disruption of bone circulation. The microcirculation is not merely a passive conduit for blood flow, but plays an active role in controlling bone processes such as osteochondral ossification.

DISCUSSION

The pathophysiology of bone circulation has been associated with osteonecrosis, but more and more evidence is pointing to the importance of bone circulation in fracture repair and osteoporosis, both of which are potentially very exciting areas for future studies.

Osteitis

Infections of the locomotive system appear in many different forms such as acute inflammation of joints or bone following injury or surgical or chronic processes, often lasting for years. They demand an exact treatment plan not only to remove necrotic tissue but also for reconstruction of defects. A special problem is infection following alloplastic reconstruction of joints or spine. Multiple surgical procedures are required to hinder reinfection, restore function, and assure acceptable patient quality of life.

Concomitant Kienböck's and Preiser's diseases: a case report

Reports of simultaneous carpal avascular necrosis in more than 1 bone are rare. This is a report of simultaneous Kienböck's disease and Preiser's disease in a 50-year-old woman with a remote history of steroid use but without a history of trauma or systemic illness.

Closing radial wedge osteotomy for Preiser's disease: a case report

A case of Preiser's disease treated with closing radial wedge osteotomy is reviewed and the therapeutic effect is reported. A good result was obtained in the short term and we believe that this surgical method could become one of the choices for surgical treatment to alleviate pain in Preiser's disease.

Pathophysiology and natural history of avascular necrosis of bone

Avascular necrosis of bone (AVN) occurs as two main variants, local and systemic. Local AVN is usually caused by trauma or microtrauma; examples include primary osteonecrosis of the medial condyle, vertebral osteonecrosis, necrosis after meniscectomy, and osteonecrosis of the mandible or small bones. Systemic AVN manifests as epiphyseal necrosis or bone infarction, which is often multifocal. Little is known about the factors that trigger AVN. One possible mechanism is intraluminal obliteration of blood vessels by microscopic fat emboli, sickle cells, nitrogen bubbles (caisson disease), or focal clotting due to procoagulant abnormalities. Extraluminal obliteration may result from elevated marrow pressure or increased marrow fat. Cytotoxicity and genetic factors may be involved also. Many factors are probably capable of inducing AVN, and combinations of factors may be required, although the final mechanism is always critical ischemia. The natural history of AVN is better understood than the early triggering factors. AVN becomes detectable 1-6 months after exposure to an easily identifiable risk factor such as high-dose glucocorticoid therapy or femoral neck fracture. Later on, AVN is uncommon even when the patient remains exposed to the risk factor. The turning point in the natural history of AVN is subchondral plate fracture, which leads to collapse of the necrotic segment of the epiphysis, usually within the first 2 years. The risk of collapse depends chiefly on the initial size and location of the necrotic segment, which can be determined accurately by magnetic resonance imaging (MRI). This natural history has obvious clinical implications.

Osteoarticular Manifestations of Antiphospholipid Syndrome

In conclusion, arthralgias represent a rather common osteoarticular manifestation of primary and secondary APS, while arthritis is mainly described in SLE-related APS. Osteonecrosis is frequently described in association with aPL in patients with and without autoimmune disorders. The presence of osteonecrosis in primary APS patients in the absence of corticosteroid use suggests an association between osteonecrosis and APS. Clinicians should be aware of this possible clinical manifestation of APS, because early diagnosis may lead to early management. A systematic screening for aPL in all cases with diagnosed osteonecrosis in the absence of precipitating factors should be considered.

Percutaneous drilling for the treatment of secondary osteonecrosis of the knee

Osteonecrosis of the knee comprises two separate disorders, primary spontaneous osteonecrosis which is often a self-limiting condition and secondary osteonecrosis which is associated with risk factors and a poor prognosis. In a series of 61 knees (38 patients) we analysed secondary osteonecrosis of the knee treated by a new technique using multiple small percutaneous 3 mm drillings. Total knee replacement was avoided in 59 knees (97%) at a mean follow-up of 3 years (2 to 4). Of the 61 knees, 56 (92%) had a successful clinical outcome, defined as a Knee Society score greater than 80 points. The procedure was successful in all 24 knees with small lesions compared with 32 of 37 knees (86%) with large lesions. All the procedures were performed as day cases and there were no complications. This technique appears to have a low morbidity, relieves symptoms and delays more invasive surgery.

Arthroplasty for advanced Kienböck's disease using a radial bone flap with a vascularised wrapping of pronator quadratus

We have performed a form of lunate replacement arthroplasty, which included excision of the lunate and insertion of a vascularised radial bone flap wrapped in pronator quadratus, for stage IIIB or stage IV Kienböck's disease, in 41 patients who have been followed up for more than three years. All patients reported an improvement in their symptoms, and 20 of the 41 became free of pain after the operation. Extension and flexion of the wrist were increased by a mean of 9 degrees and 6 degrees , respectively (p < 0.05). The radioscaphoid angle and the carpal height ratio were not significantly changed and only minimal deterioration was observed due to degenerative change. The size, density or location of the inserted bone did not change with time. A vascularised radial bone flap wrapped in pronator quadratus can be a reliable treatment option for advanced Kienböck's disease, when the pedicled bone and muscle envelope acts as a stable spacer for the excised lunate.

Numerical Predictions of the Thermal Behaviour and Resultant Effects of Grouting Cements While Setting Prosthetic Components in Bone

Acrylic cements are commonly used to attach prosthetic components in joint replacement surgery. The cements set in short periods of time by a complex polymerization of initially liquid monomer compounds into solid structures with accompanying significant heat release. Two main problems arise from this form of fixation: the first is the potential damage caused by the temperature excursion, and the second is incomplete reaction leaving active monomer compounds, which can potentially be slowly released into the patient. This paper presents a numerical model predicting the temperature-time history in an idealized prosthetic-cement-bone system. Using polymerization kinetics equations from the literature, the degree of polymerization is predicted, which is found to be very dependent on the thermal history of the setting process. Using medical literature, predictions for the degree of thermal bone necrosis are also made. The model is used to identify the critical parameters controlling thermal and unreacted monomer distributions.

Treatment of the young active patient with osteoarthritis of the hip

We compared the five- to seven-year clinical and radiological results of the metal-on-metal Birmingham hip resurfacing with a hybrid total hip arthroplasty in two groups of 54 hips, matched for gender, age, body mass index and activity level.

Function was excellent in both groups, as measured by the Oxford hip score, but the Birmingham hip resurfacings had higher University of California at Los Angeles activity scores and better EuroQol quality of life scores. The total hip arthroplasties had a revision or intention-to-revise rate of 8%, and the Birmingham hip resurfacings of 6%. Both groups demonstrated impending failure on surrogate end-points. Of the total hip arthroplasties, 12% had polyethylene wear and osteolysis under observation, and 8% of Birmingham hip resurfacings showed migration of the femoral component. Polyethylene wear was present in 48% of the hybrid hips without osteolysis. Of the femoral components in the Birmingham hip resurfacing group which had not migrated, 66% had radiological changes of unknown significance.

Kienböck's disease in a 14-year-old gymnast: a case report

Kienböck's disease is rare in children and there are few reports and therapeutic recommendations in the literature about this condition. We report a case of a 14-year-old female gymnast for whom nonsurgical treatment was followed by complete healing within 12 months. Repeated computed tomography scans provided a sequential coronal, sagittal, and transverse illustration of the progressive healing of the lunate.

[From 1878 to 2006 - working in hyperbaric conditions during tunnelling]

To review the impact of Paul Bert's researches on hyperbaric work in tunnelling, the status of the industry in 1878 is described. Mostly based on the application of Triger's machine it was used to mine coal below the water table or to dig foundations for bridges in rivers or close to rivers. The results and conclusions obtained by Paul Bert which are applicable in that particular field are listed. The major steps of research or remarkable achievements in construction between 1878 and 2006 are presented as well as the evolution of decompression tables. Improvement in safety and conditions of caisson workers has been continuous until the technical revolution resulting from the introduction and the development of tunnelling boring machines (TBM) in the late 80's. TBM technology has resulted in major changes in tunnel construction. Hyperbaric interventions have also changed completely since human operators no longer work in pressurized conditions. Only occasional inspections and repairs are carried out under pressure. Present performance in hyperbaric conditions are reported, and high pressures reached in the 2000's using saturation technology are described. The future of hyperbaric works is also discussed whether for very high pressure, or complete replacement of caisson workers in TBMs. These descriptions show that Paul Bert provides us with very clear directions to improve safety in hyperbaric conditions and that none of his recommendations were mistaken, most being still relevant.

Bisphosphonate-associated osteonecrosis of the jaw: a literature review and clinical practice guidelines

BACKGROUND

Osteonecrosis of the jaw has recently been reported as a possible adverse drug effect from bisphosphonate therapy. Reports are coming from all over the world. Norvartis, a pharmaceutical manufacturer of two implicated drug products, has notified dentists in the United States and made recommendations for dental management of cases.

MECHANISM OF ACTION

The exact mechanism of bisphosphonate effects leading to osteonecrosis of the jaw is unknown. The condition can affect both the maxilla and the mandible. Most cases developed following oral infection or dental treatment.

PREVENTION AND MANAGEMENT

Clinical guidelines for prevention and management have recently been published. Dental hygienists have a major role in patient education related to awareness of the potential drug effect and to preventive oral health education.

Range of movement in the wrist as a diagnostic tool in radial-sided wrist pain

Kienböck disease is diagnosed by imaging studies, and is often difficult to diagnose in its early stages. Our clinical impression is that wrist movement is more limited in Kienböck disease than when radial-sided wrist pain is caused by other conditions. The purpose of this study was to determine the use of wrist movement in differentiating between early Kienböck disease and radial-sided sprained wrist. We retrospectively reviewed 62 cases of Kienböck disease and 49 patients with radial-sided wrist sprain. Wrist movement at presentation was recorded. The two groups differed significantly in flexion and extension (p<0.001). The ability of movement of the affected wrist relative to the normal side to distinguish between the groups was excellent (AUC = 0.96, 0.97, respectively). The ability of wrist movement measurements to differentiate between early Kienböck disease and radial-sided wrist sprain emphasises that wrist movement should be measured prior to invasive or expensive testing.

Oxidative stress by glutathione depletion induces osteonecrosis in rats

OBJECTIVE

We recently implicated in vivo oxidative stress in the development of osteonecrosis in a steroid-induced osteonecrosis model in the domestic rabbit. In the present experiment we devised a new non-traumatic model using the rat to investigate the relationship between oxidative stress and the development of osteonecrosis.

METHODS

Seven 24-week-old male Wistar rats were subcutaneously injected with the pro-oxidant buthionine sulphoximine (BSO) 500 mg/kg for 14 consecutive days (group B) and eight rats received injections of vehicle (physiological saline; group N). The rats in both groups were killed after 14 days, and their bilateral femurs were examined histopathologically. Blood levels of reduced glutathione (GSH), total cholesterol (T-cho) and triglycerides (TG) were also determined.

RESULTS

GSH was significantly decreased in group B compared with group N (P < 0.01). No significant differences were found in T-cho or TG. Osteonecrosis was not detected in any animal in group N in contrast to five of seven animals in group B (P < 0.05).

CONCLUSION

BSO is an inducer of oxidative stress, in particular interfering with the synthesis of GSH in vivo. In the present study, GSH levels were markedly reduced by BSO, whereas neither T-cho nor TG was significantly changed. The high rate of osteonecrosis noted in group B suggests that oxidative stress alone may be sufficient to promote the development of osteonecrosis at certain sites.

Osteonecrosis: death of bone cells

Osteonecrosis is a pathologic process resulting from direct and indirect injury to the bones' vascular supply. Varying microangiopathic entities cause the death of bone. Bone cell death subsequently causes loss of joint function, impaired mobility, and microfractures leading to collapse of the joints' articular surface. The pathogenesis of osteonecrosis is presented.

[Mid-term results after proximal row carpectomy and review of the literature]

PURPOSE

The aim of this study is to evaluate the results after proximal row carpectomy and to compare them with results in the literature.

METHOD

Between 1994 and 2001, 37 patients underwent proximal row carpectomy. 30 patients were available for follow-up. In all cases the proximal row carpectomy was performed through a dorsal approach. Clinical parameters were evaluated by using the conventional wrist score (Krimmer score) as well as the DASH-score.

RESULTS

Follow-up examination shows a range of motion (ROM) for wrist extension and flexion of 46 % of the contralateral side. ROM for ulnar and radial deviation is 42 % of the other side, ROM for pronation and supination is equal to the other side. Mean grip strength is determined to be 58 % of the contralateral side. 90 % of the patients are satisfied with the result of the operation. The Krimmer score amounts to 58 and the DASH score to 39 points.

CONCLUSION

We consider proximal row carpectomy to be a good therapeutic option for lunate necrosis stage IIIB or IV or carpal collapse stage II (SNAC or SLAC wrist) with a concomitant lesion of extrinsic ligaments with ulnar translocation. Another indication is the acute, non-reconstructable or the chronic perilunar luxation with arthrosis.

Prevention and treatment of osteoporosis in chronically ill children

Osteoporosis secondary to chronic disease in children has emerged as a major health issue. As the severity of a child's illness increases, so too does the number of factors affecting their bone health. Determinants of bone health in children include level of mobility, exposure to osteotoxic medication, nutritional status, calcium and vitamin D intake, chronic inflammation and pubertal development.

Lunate resection and vascularized Os pisiform transfer in Kienböck's Disease: an average of 10 years of follow-up study after Saffar's procedure

PURPOSE

To investigate the long-term results of lunate replacement by vascularized bone transfer in advanced Kienböck's disease.

METHODS

Twenty-one patients were reviewed (mean follow-up period +/- SD, 9.9 +/- 3.5 y) to analyze results after lunate replacement by vascularized pisiform transposition (Saffar's procedure) for Lichtman stages III and IV.

RESULTS

Pain was improved in 16 of 21 patients but range of motion did not improve after surgery. Range of motion was reduced to 68% and grip power to 80% of that of the opposite hand. At follow-up evaluation the mean score on the Disabilities of the Arm, Shoulder, and Hand Questionnaire was 22.3 +/- 17.9 and the mean Cooney score was 75.4 +/- 13.2. Radiologically, Lichtman stage persisted in 8, improved in 1, progressed in 8, and could not be evaluated in 3 patients. Two patients had radiologic signs of arthritis before surgery. At follow-up examination osteoarthritis was found in 50% of patients. The majority of degenerative changes were associated with carpal collapse.

CONCLUSIONS

The replacement of the lunate by vascularized pisiform transposition maintained preoperative ranges of motion. At follow-up examination both patient satisfaction and wrist function were high. In the long term, however, Saffar's procedure can restore alignment of the carpus only partly and also results in osteoarthritis in half of all patients.

Die Kraftübertragung am Handgelenk nach Skaphoid-, Trapezium- und Trapezoideumfusion

Scaphotrapeziotrapezoid (STT) arthrodesis has been proposed to stabilise the radial column and to redirect the load away from the lunate. Midterm effects on force transmission are still unclear. Six patients who were treated with triscaphe arthrodesis were examined after an average of 5 years using CT osteoabsorptiometry of both wrists. STT arthrodesis had been performed in four cases with Kienböck's disease type IIIb and in two cases of scaphotrapeziotrapezoid arthritis. At all contralateral wrists peak mineralisations were found beyond the lunate fossa and in the scaphoid fossa of the distal radius. At the side with STT arthrodesis there was only one peak. In five cases this density maximum was beyond the scaphoid fossa and in one case half beyond the lunate and half beyond the scaphoid fossa. Triscaphe arthrodesis allows load transmission from the lunate to the radial column.

Adjusted mean Systemic Lupus Erythematosus Disease Activity Index-2K is a predictor of outcome in SLE

OBJECTIVE

To test the predictability of the adjusted mean Systemic Lupus Erythematosus Disease Activity Index-2K (AMS) for main outcomes in systemic lupus erythematosus (SLE), namely presence of damage, coronary artery disease (CAD), and avascular necrosis (AVN).

METHODS

Included in this study are patients with regular followup from the University of Toronto Lupus Clinic. This was defined as a minimum of 3 visits and no absence exceeding 18 consecutive months. For each visit, AMS was evaluated. The ability of the AMS to predict each of the main outcomes was evaluated through time-dependent covariate survival analysis. Adjustments to the regression models were made to include other risk factors such as sex, age at diagnosis (AGE), SLEDAI-2K at presentation (SLEDAI), disease duration (DD), and use of corticosteroids, immunosuppressives (IM), or antimalarials (AM).

RESULTS

Five hundred and seventy-five patients were included covering the period from 1970 to 2002. A total of 325 developed damage, 55 had CAD, and 68 had AVN. Presence of damage was not associated with sex, SLEDAI, or AM but was significantly associated with AMS, AGE, DD, and use of steroids or IM (all p < 0.001). CAD was not associated with SLEDAI or use of steroids or AM but with all other variables AMS (p = 0.046), sex (p = 0.009), AGE (p < 0.0001), DD (p < 0.0001), and IM (p = 0.035). Predictors of AVN were DD (p = 0.032) and IM (p < 0.0001) but not sex, AGE, use of steroids, AM, SLEDAI, or AMS.

CONCLUSION

AMS is associated with the presence of damage and CAD. It is not associated with AVN.

[Pain management in non-juvenile, aseptic osteonecrosis]

BACKGROUND

Adult aseptic osteonecrosis (ON) represents a clinical picture with unexplained etiology. Since curative treatment of this disease often succeeds only in the early stage, pain therapy plays an important role in the treatment process.

METHOD

We compared established and novel treatment options for ON as well as our own results after i.v. administration of the prostacyclin analogue iloprost with corresponding studies in the literature.

RESULTS

In addition to treatment with nonsteroidal antirheumatic agents and opioids, surgical "core decompression," vasoactive medications, and hyperbaric oxygenation are effective. Treatment with iloprost for 5 days resulted in highly significant pain reduction.

CONCLUSION

Symptomatic treatment is indicated in all stages of ON and curative treatment in stage I and early stage II. In cases of disease progression in the large joints, early endoprosthetic replacement is indicated to avoid secondary damage. In addition to employing vasoactive substances, a further curative treatment approach could be the use of mesenchymal stem cells.

Spontaneous wrist fusion: an unusual complication of Kienböck's disease

We report a case of spontaneous wrist fusion occurring in a patient with magnetic resonance image (MRI)-proven stage 1 Kienböck's disease. The purpose of this case report is to make hand surgeons aware of this potential finding and to alert hand surgeons and radiologists that diffuse MRI changes of the lunate may not necessarily be pathognomonic for Kienböck's disease.