Aims. Sickle cell disease (SCD) is an autosomal recessive inherited condition that presents with a number of clinical manifestations that include musculoskeletal manifestations (MM). MM may present differently in different individuals and settings and the predictors are not well known. Herein, we aimed at determining the predictors of MM in patients with SCD at the University Teaching Hospital, Lusaka, Zambia. Methods. An unmatched case-control study was conducted between January and May 2019 in children below the age of 16 years. In all, 57 cases and 114 controls were obtained by systematic sampling method. A structured questionnaire was used to collect data. The different MM were identified, staged, and classified according to the Standard Orthopaedic Classification Systems using radiological and laboratory investigations. The data was entered in Epidata version 3.1 and exported to STATA 15 for analysis. Multiple logistic regression was used to determine predictors and predictive margins were used to determine the probability of MM. Results. The cases were older median age 9.5 (interquartile range (IQR) 7 to 12) years compared to controls 7 (IQR 4 to 11) years; p = 0.003. After multivariate logistic regression, increase in age (adjusted odds ratio (AOR) = 1.2, 95% confidence interval (CI) 1.04 to 1.45; p = 0.043), increase in the frequency of vaso-occlusive crisis (VOC) (AOR = 1.3, 95% CI 1.09 to 1.52; p = 0.009) and increase in percentage of haemoglobin S (HbS) (AOR = 1.18, 95% CI 1.09 to 1.29; p < 0.001) were significant predictors of MM. Predictive margins showed that for a 16-year-old the average probability of having MM would be 51 percentage points higher than that of a two-year-old. Conclusion. Increase in age, frequency of VOC, and an increase in the percentage of HbS were significant predictors of MM. These predictors maybe useful to clinicians in determining children who are at risk. Cite this article: Bone Joint Open 2020;1-6:175–181

Osteonecrosis of femoral head is well known and recognised complication in Sickle cell disease patients. Due to the severity of the Osteonecrosis, hip pain is major limiting factor for these patients requiring total hip arthroplasty in relatively young age. We studied and report our results in total hip arthroplasty of sickle cell patients. We studied 80 patients from our combined Orthopaedic & Haematology Sickle cell clinic. Twenty four patients had painful Osteonecrosis with secondary osteoarthritis of hip and underwent total hip arthroplasty. Three patients had bilateral hip replacements. A total of twenty seven replacements were studied retrospectively. 19 patients had uncemented (Corail/Pinnacle), 5 patients had hybrid(Pinnacle/Exeter) and 3 patients had cemented(Exeter) total hip arthroplasties respectively. The patients were serially followed up for clinical and radiological assessments for loosening. Oxford hip score (OHS) was used to assess the functional outcome. The average age of the patients at the time of surgery was 38.4 (Range – 20 to 59 years. The average follow up was 5.1 years (Range – 6 months to 10 years). There were 13 female and 11 male patients. The average oxford hip score was 38.07 with 10% infection rate and 11% aseptic loosening. Arthroplasties carry high risk in patients with sickle cell disease. We report lower rates of infection and loosening rates compared to the earlier studies. Combined Haematological and Orthopaedic team input is optimal during assessment, surgery, peri-operative period and follow up. Our results of total hip replacements in sickle cell disease patients are good

Symptomatic and non-symptomatic hip osteonecrosis related to sickle cell disease (SCD) has a high risk of progression to collapse and total hip arthroplasty (THA) in this disease has a high rate of complications. We asked question about the benefit of performing an IRM to detect and treat with cell therapy an early (stage I or II) contralateral osteonecrosis. 430 consecutive SCD adult (32 years, 18 to 51) patients (225 males) with bilateral osteonecrosis (diagnosed with MRI) were included in this study from 1990 to 2010. One side with collapse was treated with THA and the contralateral without collapse (stage I or II) treated with cell therapy. The volume of osteonecrosis was measured with MRI. For cell therapy, the average total number of mesenchymal stem cells (MSCs) counted as number of colony forming units-fibroblast injected in each hip was 160,000 ± 45,000 cells (range 75,000 to 210,000 cells). At the most recent FU (20 years, range 10 to 30), among the 430 hips treated with cell therapy, 45 hips (10.5%) had collapsed and had required THA at 10 years (range 5 to 14 years) and 380 hips (88%) were without collapse and asymptomatic (or with few symptoms) with a decrease percentage of necrosis on MRI from 45% to 11%. Among the 430 contralateral THA, 96 (22.3%) had required one revision, 28 had a re-revision, and 12 a third re-revision with aseptic loosening (85% of revisions) and/or infection (6% of revisions). Hips undergoing cell therapy were approximately three times less likely to undergo revision or re-revision surgery (p < 0.01) as compared with hips undergoing a primary THA. THA is the usual treatment of collapsed ON in patients with SCD. In this population, it is worth looking with MRI for an early stage on the contralateral hip and performing (when necessary) bone marrow cell implantation during the same anesthesia as for arthroplasty

Aim. Differentiation between bone infarction and bone infection in sickle cell disease has traditionally been difficult, even with modern imaging techniques, and widespread antibiotic use is common. Early differentiation between the two conditions would enable more appropriate targeting of radiological investigations, antibiotics and surgery, and avoid un-necessary antibiotic usage. Method. At our tertiary paediatric sickle cell centre, we have developed a sequencing protocol to be able to accurately differentiate between infection and infarction in sickle cell children using Magnetic Resonance (MR) Imaging. We have undertaken a preliminary retrospective study to analyse clinical and laboratory parameters in these children to see whether earlier differentiation prior to MR imaging is possible. Results. We identified 52 episodes in 27 patients of bony pain in sickle cell children between 2006 and 2012. In 30 episodes in 27 patients, the MR sequences used allowed accurate determination of pathology, diagnosing infarction in 19 episodes in 17 patients, and infection in 8 episodes in 7 patients. The remainder showed no evidence of acute infarction or infection despite pain. As a general trend, admission white cell counts were higher in the infection group, with a temperature on admission also being more likely. There was no significant difference in CRP or platelet count between the infarction and infection groups. Conclusion. From a small retrospective study it may be possible to identify factors making infection as a cause of bone pain in sickle cell disease more likely, enabling better targeting of urgent MR imaging and surgery and preventing un-necessary antibiotic usage. A larger, prospective study is required and is currently underway

Introduction: The treatment of end stage hip osteonecrosis in patients with Sickle cell disease presents a unique set of challenges, with patients often needing arthroplasty in young adult life. Traditionally, this group of patients has a high incidence of complications and failure. We report the early results of THR in patients managed by the single hip surgeon working as part of the comprehensive Sickle Cell service. Methods: Data was collected prospectively on all sickle patients undergoing THR at our institution. 18 patients underwent surgery with a mean age of 37 (range 25–63). There were 16 primary and 2 revisions. All patients were optimised pre-operatively with an exchange transfusion to ensure the HB SS < 30%, and all possible sites of sepsis were treated aggressively. All patients received uncemented implants with hard on hard bearings and broad-spectrum prophylactic intravenous antibiotics for 48 hours. Results: 18 patients were followed up at a mean of 25 months. Despite technical challenges, all patients had a stable hip with good resolution of pain and radiographic evidence of bony ingrowth of all components. There were 3 minor intra-operative metaphyseal peri-prosthetic fractures, which all healed satisfactorily. There was a single early dislocation that has remained stable after closed reduction. There have been no superficial or deep infections. Discussion: This study shows that THR can be performed safely in patients with sickle cell disease within the context of a multi-disciplinary team approach. Operative technique involves the use of long drills under image intensifier to prepare the femur safely and use of a modular uncemented system to address the mismatch between the metaphysis and the diaphysis

Salmonella osteomyelitis occurs infrequently in children without a sickle cell disease, and its subacute form is rare. Diagnosis is often delayed because its slow onset, intermittent pain and it can be confused with bone tumors. An otherwise healthy 13-year-old boy was admitted from another center in order to discard bone tumor in proximal tibia, with compatible radiologic findings. There was no history of trauma or previous illness. Twenty days ago, he had flu symptoms and myalgia. On the physical examination the child was feverless, showed increased heat over his left knee, considerable effusion and painful restriction of movement. Inflammatory laboratory results revealed erythrocyte sedimentation rate 46mm/h and C-Reactive protein, 11,2 mg/L. Radiographs revealed a lytic lesion localized in the proximal metaphysis and epiphysis. The MRI showed an area of edema around the lytic lesion and surrounding soft tissues. Images supported the diagnosis of subacute osteomyelitis, (Brodie abscess). Empirically, intravenous cefuroxime was started. Forty-eight hours post admission, the patient underwent abscess surgical debridement, washout and cavity curettage. Samples were sent for cytology, culture and sensitivity and acid fast bacilli culture and sensitivity. Collection´s count cell was 173.000/ L white cells. Collection´s culture revealed Salmonella B sensitive to ciprofloxacin. Stool culture did not yield any growth. Intravenous cefuroxime was administered during 10 days. The patient responded well as evidenced by clinical and laboratory improvement He was discharged with his left leg immobilized in a cast during 1 month and treatment was completed with oral ciprofloxacin 500mg /12 h during 2 months. The patient had full range of knee motion after 2 months. Last reviewed, after two years of the income, he was completed recovered, and the radiograph showed bone healing without physeal neither damage nor limb leg discrepancy. The most effective therapy of a confirmed salmonella osteomyelitis is a combination of radical operative intervention and targeted intravenous antibiotics as in our case. Faced with a subacute osteomyelitis, we have to remember that it may mimic bone tumors. We highlight the isolation of Salmonella B in a patient without sickle cell disease

Introduction: Osteomyelitis remains a rare diagnosis and a difficult one to make. Acute osteomyelitis in the context of sickle cell disease remains the subject of some controversy, particularly with regard to aetiology. It is known that Salmonella species are more commonly the cause of acute bone infection in sickle cell patients than in patients with normal red blood cell morphology, but there has long been an argument as to whether Staphylococcus Aureus is in fact still the most common bacterial cause overall in this patient group, as it is in the population overall. We present a consecutive case series of 12 cases of acute osteomyelitis in paediatric patients in East London over the last twenty years. Materials and Methods: Retrospective review of 12 consecutive cases. Medical Notes along with microbiology records and radiographic results were cross referenced with a paediatric sickle cell data base held by the haematology department. Results: 10 of the 12cases had an organism isolated from either blood or bone culture(s). Salmonella spp in cases, S. Aureus in 2 cases and Pseudomonas in the remaining case. Discussion: The question of causative organism is complicated by the fact that most case series’ have bracketed adults and children together, and that conflicting conclusions have resulted from quite small, usually retrospective studies at different times and from different parts of the world – Nigeria, Saudi Arabia and the United States of America. It appears that endemicity is a result of many factors including age; race and socioeconomic factors all play a role. Conclusion: These results reveal that in our paediatric sickle cell population, Salmonella infection occurs ore commonly than Staphylococcus

18 Patients with SCD and 2ndry Osteoarthritis of their hips due to Avascular Necrosis underwent uncemented THA.

There were 12 male and 6 female patients.

Patient had their pre op WOMAC/SF-36/HOOS/and Oxford hip scores recorded preoperatively a well as 3 month, 6months and one year post op.

The outcome scores at one year were significantly better than the pre operative scores

However, when compared to a matched cohort of patients who underwent THA for reasons other than SCD/AVN, e.g. primary OA, rheumatoid arthritis, post traumatic OA, the WOMAC pain score improvement was less.

Hypoxic Inducible Factor and Hypoxic mimicking agents (HMA) trigger the initiation and promotion of angiogenic-osteogenic cascade events. However, there has been paucity of studies investigating how HIF could be over expressed under chronic hypoxic conditions akin to that seen in sickle cell disease patients to help form a template for tackling the matter of macrocellular avascular necrosis. Angiogenesis and osteogenesis are tightly coupled during bone development and regeneration, and the hypoxia-inducible factor-1 alpha (HIF-1) pathway has been identified as a key component in this process studies have shown. There are still no established experimental models showing how this knowledge can be used for the evaluation of bone implant integration and suggest ways of improving osseointegration in sickle cell disease patients with hip arthroplasty and thereby prevent increased implant loosening. The aim of this study is to help develop an in vitro experimental model which would mimic the in vivo pathologic state in the bone marrow of sickle cell disease patients. It also seeks to establish if the hypoxic inducible factor (HIF) could be over expressed in vitro and thus enhancing osseointegration. MG63 osteoblastic cells were cultured under normoxia and hypoxic conditions (20%; and 1% oxygen saturation) for 48 and 72 hours. Cobalt chloride was introduced to the samples in order to mimic true hypoxia. Cells cultured under normoxic conditions and without cobalt chloride was used as the control in this study. The expression of the hypoxic inducible factor was assessed using the reverse transcriptase qualitative polymerase chain reaction (RT-qPCR). There was increased expression of HIF1-alpha at 72hours as compared to 48hours under the various conditions. The level of expression of HIF increased from 48hrs (mean rank= 4.60) to 72hrs (mean rank =5.60) but this difference was not statistically significant, X2(1) = 0.24, p =0.625. The mean rank fold change of HIF in hypoxic samples decreased compared to the normoxic samples but this difference was not statistically significant, X2(1) = 0.54, p= 0.462. Therefore, the expression of HIF is only increased with prolonged hypoxia as seen in the 72hours samples. The expression of HIF increased in samples with CoCl2 (mean rank=5.17), compared with samples without CoCl2 (mean rank 4.67), however this was not statistically significant, X2(1) = 0.067, p=0.796, p value > 0.05. The over expression of HIF was achieved within a few days (72hours) with the introduction of Cobalt Chloride, which is a mimetic for hypoxia similar to the in vivo environment in sickle cell disease patients. This is an in vitro model which could help investigate osseointergation in such pathologic bone conditions

Abstract. Introduction. Secondary osteonecrosis of the knee affects young population and causes bilateral extensive lesions. Arthroplasty is the last resort in younger population and joint preserving options questionable in pathological bone. Conservative measures have shown failure in multiple studies and hence no gold standard treatment advocated. We aimed at identifying and analysing various treatment options for secondary osteonecrosis with respect to the outcomes and studying features of symptomatic secondary osteonecrosis with regards to demographic pattern, radiological features and causative factors. Methods. A systematic review of literature was performed in accordance with the Cochrane handbook for systematic reviews and reported according to the PRISMA guidelines. Results. Six studies which included a total of 192 patients with data on 240 knee joints were included in the final review. Follow up period ranged from 1 year to 16 years. The mean age of the patients was 34.7. 3 studies were on arthroplasty and 3 on joint preserving interventions. Majority of patients were in Stage 2 or Stage 4 of osteonecrosis. Steroid induced osteonecrosis was the majority followed by SLE and sickle cell disease. The pooled analysis showed an improvement of pre-operative knee score from 50.47 to 89.21 post-operatively. The pooled effect size for failure rate was 8.7% in joint preserving interventions and 9.2% in joint replacement group. Conclusion. Joint preserving techniques with bone marrow aspirate infiltration showed promising functional outcome and to a certain extent reversal of the pathological process. For advanced stages with subchondral collapse cemented arthroplasty showed satisfactory functional outcomes

Purpose of the study: Infection is a leading cause of morbidity and mortality in sickle cell anemia children. It often triggers an acute episode of anemia with thrombosis. Bone and joint infections are particularly frequent. Diagnosis can be difficult and is sometimes established late. Material and methods: We analyzed retrospectively the cases of 39 children with sickle cell anemia who presented one or more bone and joint infections during a six-year period (January 1998-December 2003). Results: Bone and joint infection involved 14% of all sickle cell children hospitalized during the study period. Mean age was nine years, with no gender predominance. Homozygous subjects were more exposed to infection (73%). The infection revealed the disease in 13% of the children. The rate of bone and joint infection was 62% compared with 38% for osteomyelitis; salmonella were isolated in 38% of cases. Medical treatment with adapted antibiotics and plaster cast immobilization were instituted in all cases and associated with surgical treatment in 25% (arthrotomy for evacuation of purulent collections, cleaning, resection of infected tissue). Outcome was favorable in 77% of cases (cured infection, resumed school activities). Discussion: The frequency of bone and joint infections in sickle cell anemia children in our series was similar to that reported in the literature (10–19%). Compared with children with normal hemoglobin, bone and joint infection in sickle cell anemia children present specific features in terms of localization, blood chemistry findings, causal bacteria, radiographic signs, and therapeutic modalities and sequelae. Conclusion: Sickle cell anemia is a serious hereditary disease. The risk of complications should lead to the development of preventive measures (screening at risk couples, institution of a prenuptial certificate, allogenic bone marrow graft)

It is well documented that implant loosening rate in sickle cell disease patients is higher than that seen in patients with hip arthroplasty from other indications. The Hypoxic inducible factor(HIF) - is activated in the microcellular hypoxic environment and this through a cascade of other enzymatic reactions promotes the activity of other factors and further help enhance angiogenesis and osteogenesis. The aim of this study was to investigate and propose a potential model for investigating osseointegration in a hypoxic microcellular environment using osteoblasts(MG63). Human MG63 osteoblastic cells were cultured under normoxia and hypoxic conditions (20%; and 1% oxygen saturation) for 72 hours under two different condition- with and without cobalt chloride. The samples cultured under normoxic condtions without cobalt chloride acted as control. Using qualitative polymerase chain reaction-(qPCR) - HIF expression was assessed under the above conditions in relation to the control. The results showed there was significant expression of the HIF 1 alpha protein under hypoxic condition with cobalt chloride in comparison with the control samples- all at 72hours incubation. Mann-Whitney U test was used to deduce level of significance of fold change.(p=0.002; <0.05). This was deemed as being a significant difference in the level of expression of HIF compared to the control. The results show that the hypoxic inducible factor can be expressed using the above tested. experimental invitro-model with significant results which can be a foundation for further research into improving hip implant prosthesis design to help enhance osseo-integration in sickle cell disease patient with AVN

We questioned about bearing surface and infection in two populations of patients who had bilateral THA with different bearings performed in the same hospital by the same surgical team from the year 1981 to the year 2010 (mean followup 15 years; 7 to 35). 1) first population (mean age 32 years): 325 patients (650 hips) with sickle cell disease (SCD) with two different bearing on each side. 116 patients had Metal on PE (MoP) on one side and Ceramic on PE (CoP) on the contralateral; 106 patients had (CoP) and Ceramic on Ceramic (CoC); 103 patients had MoP and CoC. 2) matched control population (same age, same period) of 820 patients without co-morbidities: 354 patients had MoP and CoP; 237 had CoP and CoC; 229 had MoP and CoC. Among the 2290 hips, 3 early (less than 12 months) unilateral infections (2 in the controls, 1 in the SCD), and 59 late unilateral infections: 23 (1.4%) in 1640 THAs control, versus 36 (5.5%) in the SCD 650 THAs (P < 0.0001) during the observation period of 35 years. In control group with the Kaplan-Meier analysis, increase infections over time but different (p=0.02) for each bearing surfaces, respectively from 0% at one year to 0.4% revision (2 cases) at most recent follow-up for 466 CoC hips, from 0% to 1.1% (7 cases) for 591 CoP hips, and from 0.3% to 2.4% (14 cases) for 583 MoP hips. In sickle cell disease group MoP hips had higher risk of infection (26 among 219) when compared with CoP (9 among 222; p=0.002), and CoC (1 among 209 hips; p=0.0004); with increase over time from 1% at one year to 4% with CoP, and from 1% to 11.8% with MoP. When contralateral hip of same patient is control, PE components are more prone to infection than those involving ceramic-on-ceramic

Introduction: Osteonecrosis of the hip is a devastating disease that often results in the collapse of the femoral head and secondary osteoarthritis of the hip. Although total hip arthroplasty is considered the main therapeutic option in cases of advanced osteonecrosis (Ficat stage III or IV), historically high failure rates have been reported for this treatment. Variables such as, whether or not the prosthesis was cemented, year of implantation, age, various medical comorbidities, and risk factors such as alcohol abuse, corticosteroids usage, autoimmune disease, or sickle cell anemia may lead to better or worse outcomes. The purpose of this study was to determine which factors were associated with risk for failure concerning total hip arthroplasty (THA) for osteonecrosis of the femoral head from a complete meta-analysis of the literature. Methods: A systematic review utilizing the Medline bibliographic database found 35 studies meeting our inclusion criteria that were related to osteonecrosis encompassing 557 hips in 443 patients. These reports were published between the years 1989 to 2007. The mean follow-up was 6.7 years (range, 3 – 10). The study population comprised of 60% men who had a mean age of 47 years (range, 17 to 90). The most frequent associated risk factors for osteonecrosis were corticosteroid usage (26.2%) and alcohol abuse (30.1%). The final outcome parameters were number and percentage of patients who underwent revision surgery, who had impending radiographic failure, such as osteolytic lesions in close proximity to the implant, or who were clinical failures. Clinical failure was defined as a value less than 70% of the maximum score of the relevant hip scoring system used. All reviewed studies were divided into cemented, cementless, or hybrid fixation, as well as year of implantation (before and after 1990). In addition, patients were stratified according to comorbidities, age, gender, and various diagnostic and other risk factors (e.g. systemic lupus erythematosus, sickle cell disease, use of corticosteroids, alcohol abuse). Results: Overall, there were 131 poor outcomes out of 557 hips (23.5%). Seventy-six revision surgeries were performed, with another 55 hips showing either radiographic signs of loosening or clinical failures. Cemented THA had a failure rate of 17.9%, while the cementless THA had a failure rate of 24.5%. Overall outcomes were different for various risk factors; intake of corticosteroids led to a failure rate of 42.3%, alcohol abuse; 38.1%, posttraumatic disorders; 39%, and sickle cell anemia; 45.5%. Patients without known adverse risk factors had only 17% failures. Discussion: Our findings further emphasize the poor results of total hip arthroplasty in patients with various risk factors such as alcohol abuse, use of corticosteroids, lupus, and sickle cell anemia. It also appears that patients without these adverse risk factors have a better survival rate. The importance of this study is that it may help the surgeon understand the risk of total hip arthroplasty in various stratified groups in patients with osteonecrosis

To investigate the underlying mechanism of osteocyte death in osteonecrosis of the femoral head (ONFH). Although there are a plethora of conditions that predispose to ONFH the underlying mechanism that results in the death of osteocytes is poorly understood. Consequently, treatment for early disease has a variable outcome. Recent investigation has focussed on the role of nitric oxide (NO) in the local control of bone turnover. NO is central to bone cell metabolism and has been implicated in the development of apoptosis. Bone samples were harvested from the femoral heads of 40 patients undergoing total hip arthroplasty – 20 for advanced ONFH and 20 for osteoarthritis (control group). Immunocytochemical techniques were used to demonstrate evidence of NO synthase (iNOS and eNOS) as a marker of NO production and for evidence of apoptosis. There was a marked increase in the expression of both eNOS and iNOS in the bone marrow and osteocytes from patients with ONFH secondary to steroids and alcohol with a correspondingly high proportion of apoptotic cells. Very little evidence of either eNOS or iNOS could be demonstrated in the control group and no significant apoptosis could be demonstrated. Samples from patients with ONFH secondary to sickle cell disease likewise had little evidence of apoptosis and a less marked increase iNOS production. Our findings suggest that sickle cell disease may cause infarction of bone which subsequently leads to osteonecrosis. However, steroids and alcohol, or their metabolites, may have a direct cytotoxic effect upon bone leading to an increased NO production and NO-mediated apoptosis rather than necrosis. Our findings may provide important clues as to the underlying pathway leading osteocyte death. Therapeutic measures aimed at preventing production of toxic levels of NO or by blocking specific pathways in apoptosis may provide effective an treatment during the early stages of ONFH by halting disease progression

Successful nonarthroplasty solutions for the treatment of osteonecrosis of the femoral head continued to be sought. However, no definitive nonarthroplasty solutions have to date been found. Hence, even in the best of hands a large number of patients with osteonecrosis end up with debilitating end-stage osteoarthritis. In the inception of total hip arthroplasty (THA), the results of treatment of femoral head osteonecrosis by THA were inferior to total hip replacement performed for osteoarthritis. Reasons for this included the young age of many osteonecrosis patients, the high numbers of comorbidities in this population (SLE, sickle cell anemia, alcoholism), and the poor bone quality at the time of surgery. Arthroplasty considerations included bipolar replacement, hemiresurfacing, resurfacing (non metal-on-metal and later metal-on-metal), cemented total hip arthroplasty and cementless total hip arthroplasty. Previous to the use of cementless arthroplasty, all of these procedures had a relatively high 5 to 10 year failure rate of 10–50%. Even our own 10-year results using contemporary cementing techniques demonstrated 10% failure compared to 1–2% failure in our nonosteonecrosis patients. For this reason, it made sense to continue exploring nonarthroplasty solutions for osteonecrosis of the hip. The introduction of cementless fixation for total hip arthroplasty changed the entire thinking about hip osteonecrosis treatment for many of us. Although initially we were concerned about whether bone would grow into the prosthesis in the environment of relatively poor bone, the early results demonstrated that it can and does. Most recently, with the use of crosslinked polyethylene, the cementless construct gives many of us hope that with cementless fixation, the treatment of many patients including the young (especially if followed closely to exchange bearing surfaces if necessary) will last a lifetime with THA being the only and definitive procedure. Our most recent 10-year results demonstrated a femoral stem revision rate of 1.5% will all other stems (other than the stem revised) bone ingrown. Acetabular fixation was also 100% and although 6% required liner exchange, our own and others' results with crosslinked polyethylene would suggest that this problem should be markedly reduced

Osteomyelitis is usually related to trauma, surgery, immunocompromised patients, IV drug abuse, poor vascular supply, diabetes, sickle cell disease or peripheral neuropathy. We report an unusual case of femur osteomyelitis without any of these risk factors. A 31 years old male, light smoker, presented at the Emergency Room for pain in the left thigh for about a month, without any previous event. He had 2 previous visits to the hospital with similar diffuse complaints interpreted as irradiated low back pain. He was pale, feverish but no signs of local inflamation. His left knee ROM was 30°-15°-0°. He had no neurologic deficits. Blood tests showed high WBC count and PCR (400mg/L). After contrasted CT showing an 1,2×6×2,5cm abcess the patient was taken to the OR for irrigation and debridment. The day after the patient did a MRI that showed extended femur osteomyelitis and adjacent myositis (images). He underwent new surgery for a more extensive irrigation and debridment, femur medular canal included, from where a large pus quantity erupted. The hemocultures and bone biopsys, revealed a Multissensible Strep. Alfa-hemolitic (S. anginosus) and appropriate antibiotherapy was implemented (Amoxicillin/Clavulanate). He slowed improve till 11th day when he showed rise of PCR and a new MRI showed the same inflammatory process. He underwent new surgery but no pus was visible. He gradually improved, started hyperbaric oxygen therapy and was discharged on the 28th day after the first surgery, continuing antibiotherapy at home for a total of 8 weeks. Transthoracic Ecography was normal, as well Brucella, HIV, and other serologies. Three weeks later, the patient again presented to the ER with fever and rise of inflammatory markers in blood, consistent with recurrence of the infection. The patient was taken to the OR for surgical debdridment and irrigation, but this time the cultures showed a multissensible Gemella haemolysans, possible contamination during the hyperbaric oxygen therapy sessions. This is the case of a healthy young adult with an idiopathic femur osteomyelitis, initially misinterpreted for irradiated low back pain, that recurred after the first medical and surgical successful treatment, with an unusual agent

Aims

The management of fractures of the medial epicondyle is one of the greatest controversies in paediatric fracture care, with uncertainty concerning the need for surgery. The British Society of Children’s Orthopaedic Surgery prioritized this as their most important research question in paediatric trauma. This is the protocol for a randomized controlled, multicentre, prospective superiority trial of operative fixation versus nonoperative treatment for displaced medial epicondyle fractures: the Surgery or Cast of the EpicoNdyle in Children’s Elbows (SCIENCE) trial.

Currently, there are no generally accepted treatments for the prevention of osteonecrosis. To compound this further, despite considerable research efforts, the natural history of this disease remains poorly understood. The disease process appears to be initially asymptomatic, but after symptoms appear, the course becomes rapidly progressive. Clinical studies have shown that, if left untreated, collapse of the femoral head will occur in 80 per cent of the cases or greater within four years. As our knowledge of the etiology and pathogenesis of osteonecrosis improves, new treatments to halt, or at least impede, the progression of the disease may be possible. Achieving the best outcomes in the treatment of osteonecrosis depends on early, accurate diagnosis, and prompt treatment appropriate for the stage of the disease. In many cases, if treated early, long-term preservation of the native joint is possible. Magnetic resonance imaging allows accurate diagnosis in even the earliest asymptomatic stages of the disease. Non-surgical treatments such as pharmacological agents have shown promise in experimental studies, although further work remains before they are appropriate for widespread use. Various hip salvaging procedures such as core decompression, percutaneous drilling, non-vascularized and vascularized bone grafting, and various osteotomies have been successful in the majority of properly selected patients over follow-up times of a decade or more. Advances in arthroplasty technologies and techniques, including hip resurfacing and modern cementless total hip arthroplasty have allowed patients to return to pain-free, active lifestyles with excellent long-term prosthesis survival. Current treatments for osteonecrosis, while generally successful, focus on halting or delaying the progression of symptomatic disease. Recent discoveries concerning the relationship between genetic factors and the development of osteonecrosis, as well as the pathophysiologic effects of various indirect and direct risk factors such as corticosteroid use and sickle cell disease, continue to improve our understanding of the underlying disease process. While these discoveries are promising, we must continue to work towards the goal of being able to identify and treat the precursors of osteonecrosis before it progresses to symptomatic disease and threatens the survival of native joints

Intraosseous pressure measurements (IOP) are not new. Several authors have struggled to interpret static IOP and to understand arthritis and osteonecrosis pathology. This work uses a combination of simple experiments in vivo to reassess bone and joint physiology. Joint replacement needs to take into account the hydrodynamic conditions that are present in bone. Intraosseous pressure measurements were carried out with vascular occlusion, activity and saline injection in experimental conditions and then in man during walking. RESULTS. 1. Basal IOP has a pulse wave and an underlying respiratory wave (RW). 2. IOP closely reflects systemic vascular changes. 3. Proximal arterial occlusion causes loss of IOP (IOPa) and pulse volume (PV). 4. Proximal vein occlusion causes a rise in IOP (IOPv) with preservation of PV and RW. 5. Physical loading raises IOP with preservation of PV and RW. 6. Load with arterial occlusion caused minimal rise in IOP. Loading with venous occlusion caused an augmented rise in IOP with preservation of the PV. 7. Simultaneous recordings from the femoral head, condyle and upper tibia during vascular occlusion and loading show that the same effects occur at all sites. 8. Simultaneous recording from the femoral head, condyle and upper tibia during saline injection shows pressure is transmitted through bone but not across joints. 9. The Ficat bolus test destroys local circulation. Aspiration is better and preserves local perfusion. 10. Bone health at the needle tip is better assessed by IOPv – IOPa, the perfusion ‘bandwidth’. 11. Upper tibial pressure during standing, slow walking and fast walking shows large IOP changes in vivo. 12. There is probably a physiological subchondral bone blood pump. 13. Anatomical features are present which support this idea. CONCLUSIONS. IOP measurement in isolation is meaningless. With arterial and venous occlusion, perfusion at the needle tip can be studied. Compartment syndrome testing should be similar. Subchondral bone is a compressible perfused sponge with a ‘pumped’ microcirculation. Very high pressures arise in subchondral bone during activity. There are protective modifications of the microcirculation. Failure of subchondral circulation causes arthritis. Arthritis is mainly a ‘vasculo-mechanical’ disease. This work explains the spectrum of arthritis and osteonecrosis, and Perthes, caisson and sickle cell disease patterns. It explains why osteoporosis might protect against arthritis