Aims: PMMA is currently used as grouting agent of arthroprostheses and for filling of bone cavities after bone curettage. It is moreover used as a carrier of antibiotics in the local treatment of bone infections and it has been proposed as a carrier of antiblastic drugs in the local treatment of bone metastases. The aim of this study is to analyse the biological properties and compressive strenght of PMMA-Methotrexate mixture to be used for the local treatment of bone metastases. Methods: Cylinders of PMMA containing Methotrexate in different concentrations were manufactured according to ASTM F-451. Cylinders of PMMA were used as control. The porosity of the cylinders was characterised by SEM. Drug elution rate in saline solution was measured by HPLC. The biological activity of Methotrexate was analysed on human breast cancer cells using MTT test at different time (from 5 minutes to 30 days). Compressive tests was performed in conformity to ASTM F-451 on PMMA- Methotrexate samples and control as-made and after 30 days of aging in saline. Results: SEM analysis showed the presence of granules of Methotrexate on the surface of as-made cylinders that can be readily released from PMMA cylinders. The release occurred in large amount within 24 hours after immersion. We observed a relative release rate is more sustained in samples containing the drug in lower concentration. Also the biological activity was time dependent: cell death decreased progressively from 60% at 24 hours to 10% at 30 days. Compressive tests showed no statistical differences between PMMA cylinders containing Methotrexate and controls before and after aging in saline. Conclusions: The results show that PMMA-Metho-trexate may be considered an interesting option in the treatment of bone metastases because cement allows mechanical resistance after bone curettage or resection and Methotrexate improves locally anticancer activity

The August 2024 Wrist & Hand Roundup. 360. looks at: Methotrexate shows potential in reducing pain for hand osteoarthritis with synovitis; Circumferential casting versus plaster splinting in adult distal radius fractures: the CAST study findings; Surgery shows superior long-term success for Dupuytren contracture compared to needle fasciotomy and collagenase injection; Evolving trends in surgical management of wrist arthritis: a decade-long national analysis; Mid-term outcomes of three commonly used surgical reconstructions for scapholunate instability; SLAC and SNAC: what is the evidence for treatment?; Steroids for trapeziometacarpal osteoarthritis?; When is it safe to return to driving after distal radius fracture fixation? A prospective study

The aim of our study was to increase of survival of children with osteosarcoma by intensification of chemotherapy by inclusion of high dose methotrexate. 53 patients were treated in our centre between 2003 and 2007. Age are ranged from 5 to 16 years. 23 (43,4%) patients had metastetic disease. Polychemotherapy consist of alternating courses of CDDP, adriamicin, ifosfamide and etoposide and high-dose methotrexate (8–12 g/m. 2. ). In 25 (51%) cases have been received objective response (CR+PR). 38 (71,7%) patients alive at present time. 2 patients died from complications of treatment. 7 patients had PD, 1 — local relapse, 4 — metastatic relapse, 1 — combined relapse. 2-year OAS was 75,2±6,8%, 2-year RFS was 65±7,8%

We investigated the possible use of acrylic cement containing chemotherapeutic drugs in the treatment of malignant lesions in bone. The diffusion of methotrexate (MTX) from methylpolymethacrylate implants was studied in vitro: polymerisation of the cement did not destroy the drug; liberation began immediately and about 10% was released by 18 hours. Some release continued for as long as six months. In vivo experiments on rats with induced osteosarcoma showed that MTX in cement had both local and general effects which were dependent on the dosage. A series of 17 large dogs with spontaneous osteosarcoma were then treated by local resection and cement containing MTX. General chemotherapeutic effects were detectable from 2 hours to 5 days, survival was increased and local recurrence was reduced, but there were four cases of delayed wound healing. Preliminary studies in human patients confirm the possibility that this method of local chemotherapy could be a useful addition to the treatment of malignant tumours of bone

Bone tumours may recur locally even after wide surgical excision and systemic chemotherapy. Local control of growth may be accomplished by the addition of cytostatic drugs such as methotrexate (MTX) to bone cement used to fill the defect after surgery and to stabilise the reconstructive prosthesis. We have studied the elution kinetics of MTX and its solvent N-methyl-pyrrolidone (NMP) from bone cement and their biological activities in five cell lines of osteosarcoma and in osteoblasts, and compared them with the effects of the parent compounds alone and in combination. Our findings show that MTX is released continuously over months at concentrations highly cytotoxic to osteosarcoma cells and suggest that the impregnated bone cement would be effective in the long term. Proliferating osteoblasts, however, were much less sensitive towards MTX. The dose-response relationship for NMP and experiments with MTX/NMP-mixtures show that the eluted concentrations of solvent are not toxic and do not influence the effects of MTX. We suggest that bone cement containing MTX dissolved in NMP releases the drug in a suitable and effective way and may be of value in the treatment of bone tumours

Summary. Methotrexate chemotherapy (commonly used in treating cancers and rheumatoid arthritis) creates an inflammatory condition in bone, decreasing osteogenesis, enhancing adipogenesis, increasing osteoclastogenesis, leading to bone loss and marrow adiposity; treatment with fish oil or folinic acid counteracts these negative effects and prevents bone loss. Introduction. Chemotherapy with anti-metabolite methotrexate (MTX) is commonly used in treating cancers and rheumatoid arthritis; however it is known to cause bone loss for which currently there are no adjunct preventative treatments. Methods and Materials. Using a rat model, this study investigated the damaging effects in bones caused by daily MTX injections (0.75mg/kg) for 5 consecutive days (mimicking induction phase treatment for childhood leukaemia) and also the potential protective benefits of omega-3 fatty acid-rich fish oil at different doses (0.25, 0.5 or 0.75 mL/100g BW) in comparison to antidote folinic acid (given i.p at 0.75mg/kg 6 hours post MTX, which is clinically used to reduce MTX toxicities in soft tissues). Results. Histological analysis showed that MTX significantly reduced primary spongiosa bone height and metaphyseal trabecular bone volume. MTX also significantly reduced density of osteoblasts at the secondary spongiosa. Ex vivo differentiation assays with bone marrow stromal cell populations of treated rats revealed a significant reduction in osteogenic differentiation but an increase in adipogenesis. Consistently, RT-PCR gene expression study within the stromal cell population revealed a lower expression of osteogenic transcription factors Runx2 and Osx and bone matrix protein osteocalcin but a significantly upregulated adipogenesis-related genes FABP4 and PPARγ, indicating that MTX chemotherapy induces a switch in the differentiation potential towards adipogenesis at the expense of osteogenesis. MTX increased the density of osteoclasts within the metaphyseal bone as revealed by histological analysis and osteoclast precursor cell pool as shown by ex vivo osteoclastogenesis assay with bone marrow samples. Consistently, mRNA expression of proinflammatory and osteoclastogenic cytokines IL-1, IL-6, TNF-α, and the RANKL/OPG ratio were significantly upregulated by MTX. Supplementary treatment with fish oil (0.5mL/100g BW) or folinic acid significantly preserved metaphyseal trabecular bone volume, osteoblast density, and bone marrow stromal cell osteogenic differentiation and suppressed MTX-induced adipogenesis. These supplements also prevented MTX-induced increased osteoclast density, osteoclastogenesis, and expression of proinflammatory and osteoclastogenic cytokines. Conclusion. These results suggest that MTX chemotherapy creates an inflammatory condition in bone resulting in increased osteoclast formation and decreased osteoblast formation thus leading to bone loss, and that supplementary treatment with fish oil at 0.5mL/100g BW or folinic acid counteract these negative effects, helping to conserve bone formation, suppress bone resorption and bone marrow adiposity, and thus prevent bone loss during MTX chemotherapy

Aims. To assess the correlation between the histological response to preoperative chemotherapy and event-free survival (EFS) or overall survival (OS) in patients with high-grade localized osteosarcoma. Methods. Out of 625 patients aged ≤ 40 years treated for primary high-grade osteosarcoma between 1997 and 2016, 232 patients without clinically detectable metastases at the time of diagnosis and treated with preoperative high-dose methotrexate, adriamycin and cisplatin (MAP) chemotherapy and surgery were included. Associations of chemotherapy-induced necrosis in the resected specimen and EFS or OS were assessed using Cox model and the Pearson’s correlation coefficients (r). Time-dependent receiver operating characteristic analysis was applied to determine the optimal cut-off value of chemotherapy-induced necrosis for EFS and OS. Results. OS was 74% (95% confidence interval (CI) 67 to 79) at five years. Median chemotherapy-induced necrosis was 85% (interquartile range (IQR) 50% to 97%). In multivariate Cox model, chemotherapy-induced necrosis was significantly associated with EFS and OS (hazard ratio (HR) = 0.99 (95% CI 0.98 to 0.99); p < 0.001 and HR = 0.98 (95% CI 0.97 to 0.99); p < 0.001, respectively). Positive correlation was observed between chemotherapy-induced necrosis and five-year EFS and five-year OS (r = 0.91; p < 0.001, and r = 0.85; p < 0.001, respectively). The optimal cut-off value of chemotherapy-induced necrosis for five-year EFS and five-year OS was 85% and 72%, respectively. Conclusion. Chemotherapy-induced necrosis in the resected specimen showed positive correlation with EFS and OS in patients with high-grade localized osteosarcoma after MAP chemotherapy. In our analysis, optimal cut-off values of MAP chemotherapy-induced necrosis in EFS and OS were lower than the commonly used 90%, suggesting the need for re-evaluation of the optimal cut-off value through larger, international collaborative research. Cite this article: Bone Joint J 2020;102-B(6):795–803

Introduction. In rheumatoid (RA) patients undergoing total joint arthroplasty, evidence suggests methotrexate should be continued without increase in post-operative infection. Prednisolone increases post-operative infection risk, but cannot be stopped without risk of Addisonian events. Insufficient evidence exists to clarify perioperative biologic agent management. We currently stop biologics 2 weeks prior to operation and reintroduced following wound healing. Patients/Materials & Methods. This service evaluation reviewed infection rates and length of stay in RA patients following lower-limb arthroplasty, on various anti-rheumatoid therapies across a 28-month period. Results. Forty cases were identified: 15% on no anti-rheumatoid treatment, 45% on mono-therapy (8 on methotrexate, 8 on prednisolone, 2 on biologics)) and 40% on combination-therapy. The total population post-operative infection rate was 18% (all superficial wound). Mean length of stay was 8.0 days (SD=6.8). Methotrexate takers had an infection rate of 5% versus 33% in non-methotrexate takers (p=0.017), and a length of stay of 6.5 days versus 9.9 days in non-MTX takers (p=0.005). Prednisolone takers had an infection rate of 37% versus 0% in non-prednisolone takers (p=0.002) and length of stay was 12.0 days versus 4.7 days in non-prednisolone takers days (p=0.006). Biologics takers had similar infection rates of 9% versus 21% in non-biologic takers (p>0.05), and a similar length of stay of 6.6 days versus 8.6 days in non-biologic takers (p>0.05). Discussion. This data supports current evidence that methotrexate should be continued without detriment to infection risk and length of stay. Biologic agents stopped 2 weeks prior to operation appear to have no effect on infection rate and length of stay. Patients on prednisolone should be identified as at a higher risk of infection and should plan for a longer length of stay. Conclusion. Larger scale cohort studies are required to determine whether biologic agents should be continued per-operatively

Introduction. Chronic recurrent multifocal osteomyelitis (CRMO) is a rare condition characterised by bony pain and swelling which may be initially mistaken for bacterial osteomyelitis. The episodic course of the disease may confound the diagnosis and potentially be mistaken for a partial response to antimicrobial therapy. It is an orphan disease and consequently results in many unclear aspects of diagnosis, treatment and follow up for patients. The aim of this study is to evaluate a national tertiary centre's experience with the clinical condition and present one of the largest cohorts to date, emphasizing the vast array of clinical spectrum, course and response to treatment. Methods. We retrospectively evaluated all children identified with CRMO from the period 2000–2022 within Wales. Demographic data and clinical parameters were selectively identified through the utilisation of a national clinical platform (Welsh Clinical Portal). The diagnosis was based on clinical findings, radiological images, histopathological and microbiological studies. Results. A total of 21 patients were identified as suitable for inclusion. The mean age of diagnosis was 9.4 ±2 years. The age range of children being diagnosed was 6–14 years. Of the 21 patients, only 2 reported feeling unwell prior to their first presentation with generalized coryzal illness reported. The most common presenting site for CRMO was knee (33%) followed by back pain (28%). 19% of the included cases at initial presentation had localised warmth and had nocturnal pain. 4 of the patients went on to have dermatological conditions of which psoriasis was the most common (14%). Bilateral symptoms developed in 38% of the included patients. Biochemical investigations revealed only 19% of patients had a raised C-reactive protein level and erythrocyte sedimentation rate whilst 9/21 patients went on to have a bone biopsy to aid diagnosis. 100% of patients had MRI whilst whole body MRI was utilised in 8/21 patients. NSAID's were utilised for 81%, Pamidronate for 33% and methotrexate for 14%. Biologics were utilised for a further 24% of the total population in failed medical therapy. Surgical intervention was utilised for a single individual in this cohort of patients in the form of posterior spinal stabilisation. The most common referring speciality for these patients was Rheumatology (71%) followed by Orthopaedics (33%). Discussion. CRMO represents a challenging diagnosis to make with such varied clinical and biochemical presentations for this condition. The absence of diagnostic Radiological features on X-ray could argue over early MRI imaging. The utilisation of whole body-MRI can now identify multifocal disease burden which may facilitate a timely diagnosis and ensure that effective medical treatment is started promptly without delay. This study is the largest cohort of CRMO patients conducted in this country. Future work will serve to build upon a framework and national referral pathway so that these patients can be seen by the appropriate specialist in a timely manner

Curettage and packing with polymethylmethacrylate cement is a routine treatment for giant-cell tumour (GCT) of bone. We performed an in vitro evaluation of the cytotoxic effect of a combination of cement and methotrexate, doxorubicin and cisplatin on primary cell cultures of stromal GCT cells obtained from five patients. Cement cylinders containing four different concentrations of each drug were prepared, and the effect of the eluted drugs was examined at three different time intervals. We found that the cytotoxic effect of eluted drugs depended on their concentration and the time interval, with even the lowest dose of each drug demonstrating an acceptable rate of cytotoxicity. Even in low doses, cytotoxic drugs mixed with polymethylmethacrylate cement could therefore be considered as effective local adjuvant treatment for GCTs

Juvenile idiopathic arthritis (JIA) is a chronic disease of childhood; it causes joint damage which may require surgical intervention, often in the young adult. The aim of this study was to describe the long-term outcome and survival of hip replacement in a group of adult patients with JIA and to determine predictors of survival for the prosthesis. In this retrospective comparative study patients were identified from the database of a regional specialist adult JIA clinic. This documented a series of 47 hip replacements performed in 25 adult patients with JIA. Surgery was performed at a mean age of 27 years (11 to 47), with a mean follow-up of 19 years (2 to 36). The mean Western Ontario and McMaster Universities osteoarthritis index questionnaire (WOMAC) score at the last follow-up was 53 (19 to 96) and the mean Health Assessment Questionnaire score was 2.25 (0 to 3). The mean pain component of the WOMAC score (60 (20 to 100)) was significantly higher than the mean functional component score (46 (0 to 97)) (p = 0.02). Kaplan-Meier survival analysis revealed a survival probability of 46.6% (95% confidence interval 37.5 to 55.7) at 19 years, with a trend towards enhanced survival with the use of a cemented acetabular component and a cementless femoral component. This was not, however, statistically significant (acetabular component, p = 0.76, femoral component, p = 0.45). Cox’s proportional hazards regression analysis showed an implant survival rate of 54.9% at 19 years at the mean of covariates. Survival of the prosthesis was significantly poorer (p = 0.001) in patients who had been taking long-term corticosteroids and significantly better (p = 0.02) in patients on methotrexate

A 48-year old man presented with back pain that was resistant to treatment. An MR scan showed spondylolisthesis at L4-5 and narrowing of the exit foraminae. He had a posterior fusion which did not relieve his symptoms. He continued to have back pain and developed subcutaneous nodules in both forearms. Biopsy from the skin revealed cutaneous sarcoidosis, and one from the lumbar spine showed sarcoidosis granuloma between the bone trabeculae. A CT scan of the abdomen and chest revealed axillary lymphadenopathy, mediastinal enlarged nodes, apical nodular nodes and splenomegaly. The patient was started on large doses of methotrexate and steroids. His angiotensin-converting enzyme and calcium levels returned to normal and the back pain resolved

Methotrexate and Cox-2 inhibitors are thought to interfere with bone healing. There have been controversial results published in the literature. The effect of newer antirheumatoids (Leflunomide, Etanercept, Infliximab) has not been studied. The aim of this study was to find the in-vitro effect of methotrexate, newer anti-rheumatoids, steroids and cox-2 inhibitors on Osteoblasts. Osteoblasts were cultured from femoral heads obtained from young otherwise healthy patients undergoing total hip replacement. The cells were cultured using techniques that have been previously described. A computer aided design of experiment was used as a model for setting up the experiment on samples obtained from five patients. Normal therapeutic concentration of the various antirheumatoids was added alone and in combination to the media. The cell growth was estimated after two weeks using spectrophotometric technique using Roche Cell proliferation Kit. Multiple regression analysis was done to estimate the best predictor of the final result. Patient was found to be the most significant factor (p< 0.001) in predicting the ultimate response. Cox-2 inhibitor (Etoricoxib) was found to be the next best predictor (p=0.043). Etoricoxib in fact had a stimulatory effect (R=0.219) on the osteoblast growth, which was accentuated in the presence of other agents that varied amongst different patients. Different patients respond differently to the drugs. None of the antirheumatoids inhibit osteoblast proliferation and differentiation in-vitro. If osteoblastic activity is considered to be the primary factor responsible for bone healing, then an inhibition should not result in patients who are on these drugs

Osteosarcoma rarely affects young children. To determine the clinical characteristics and the prognosis of this cancer in children of less than 5 years at diagnosis, we retrospectively analysed medical records of these patients treated in French centers between 1980 and 2007. A centralised histological review was carried out. Fifteen patients were studied. Long bones were involved in 14 cases. Metastases at diagnosis were observed in 40% of patients. Histologic type was 74% osteoblastic. In 3 cases (20%) tumours occurred on a particular background (tall constitutional size, treatment with growth hormone and pregnancy induced by clomiphene). One child had a second cancer 13 years after the first diagnosis. Twelve children received pre-operative chemotherapy including high dose methotrexate: 5 of them had progressive disease; only 36% had good histological response (less than 10% viable cells). Limb salvage surgery was performed in six cases (40%). Chemotherapy was well tolerated in most patients. A one-year-old child developed a severe late convulsant encephalopathy with lesions of the white substance that could be due to methotrexate despite adjustment of doses to his weight. The functional recovery of the three analysable children who underwent limb salvage surgery is uneven and shows frequent mechanical or infectious complications (2 to 5 reinterventions per patients). First complete remission (CR) was obtained in 12 children, six of them relapsed. With a median follow-up of 15 years, six are alive in CR, six died of disease (40%), two were lost to follow-up and one has stable disease with metastasis. This study shows that osteosarcoma seems to be more aggressive in children under five years of age. Surgical management remains difficult in this population. Prospective studies are still needed to confirm these observations

Osteosarcoma is the most common malignant bone tumour in children and young people. Approximately 40% patients respond poorly to highly toxic preoperative MAP (methotrexate adriamycin, cisplatin) chemotherapy with consequent inferior survival. The role of genetic polymorphisms in drug response and toxicity is reported in acute leukaemia and some solid tumours. Recent evidence in osteosarcoma suggests increased chemotherapy toxicity is associated with improved survival. The aim of this pilot study is to investigate the influence of drug target and metabolising gene polymorphisms on tumour response and chemotherapy toxicity in osteosarcoma. Patients who have completed MAP chemotherapy are eligible. Chemotherapy toxicity (CTCAE grade) is collected from patient records. Tumour response is graded as good (> 90% necrosis) or poor (< 90% necrosis) in resection specimen. Peripheral blood DNA is typed for genome-wide single nucleotide polymorphisms (SNP) using the Illumina 610 Quad array and analysed using Bead Studio software. Standard PCR techniques are used to genotype the Thymidylate synthase (TS) gene (folate pathway) for the presence of 2 or 3 copies of a 28 base pair repeat (2R/3R) and a G/C SNP in the 3R allele. 52 patients have entered to date: 33 good responders, 12 poor and 7 unevaluable for response. Median age 18 years (range 10–51), males:females 1.3:1. Median follow up is 39 months (range 2–76) with 11 patients relapsing. 23 patients have TS genotype 2R/2R, nineteen 2R/3R, six 3R/3R, three 2R/4R and one 2R/7R. Neither TS repeat or G/C SNP genotype correlated with histological response or degree of methotrexate stomatitis. Interestingly, presence of the 2R allele was significantly related to relapse (p=0.01) but may reflect small patient numbers. Recurrent methotrexate stomatitis (> 2 episodes of CTCAE grade 2) was weakly correlated with no relapse (p=0.07). Analysis of SNP array data with emphasis on MAP pathway polymorphisms will be presented when complete

Aims

Osteosarcoma is the most common primary bone malignancy among children and adolescents. We investigated whether benzamil, an amiloride analogue and sodium-calcium exchange blocker, may exhibit therapeutic potential for osteosarcoma in vitro.

Introduction: Osteomyelitis often causes functional impairment due to tissue destruction and the incidence of this condition appears to be increasing. Antimicrobial peptides (AP) are effectors of the innate defence system and play a key role in host protection at cellular surfaces. Human beta-defensins (HBD) represent a major subclass of antimicrobial peptides and act as a first line defence through their broad spectrum of potent antimicrobial activity (1). The aim of the present in vitro and in vivo investigations was to study the expression and regulation of HBD-2 and -3 in the case of bacterial bone infection and to analyze the effects of immunosuppressive drugs on bone-derived AP-expression. Methods: Samples of healthy human bone, osteomyelitic bone and cultured osteoblasts (primary-, hFOB- and SAOS-2 cells) were assessed for the expression of HBD-2/-3 by RT-PCR, immunohistochemistry or ELISA. Regulation of HBD-2/-3 was studied after exposure to Staphylococcus aureus (SAS) or Pseudomonas aeruginosa (PAS), proinflammatory cytokines (IL-1, 10ng/ml) and immunosuppressive drugs (glucocorticoids, methotrexate) and was assayed by ELISA. An osteomyelitis mouse model was performed to demonstrate the regulation of the murine homologues of HBD-2/-3 by real time RT-PCR and immunohistochemistry. Results: ELISA experiments demonstrated, that samples of infected bone produce higher levels of endogenous antibiotics such as HBD-2 when compared with samples of healthy bone. After exposure of osteoblasts to bacteria or proinflammatory cytokines a clear HBD-2/-3 induction was observed. Additional treatment with glucocorticoids or methotrexate prevented bacteria mediated HBD-2 induction in cultured osteoblasts. The osteomyelitis mouse model demonstrated transcriptional up-regulation of the murine HBD-homologues in bone after intra-osseous contamination of the tibia. Discussion: Our study firstly demonstrate that osteoblasts are able to produce anti-inflammatory peptides such as HBD-2 in vitro and in an animal model of staphylococcal osteomyelitis. We provide evidence for a new role of osteoblasts during infection of bone tissues, namely, the ability to produce antimicrobial peptides and modulating immune responses in inflammatory bone diseases. Immunosuppressive drugs such as glucocorticoids or methotrexate may increase the susceptibility to bone infection by decreasing AP-expression levels in case of microbial challenge. Novel approaches to management are required particularly in the era of multi-resistant bacterial strains. Current investigation will focus on the regulation of human β-Defensins in bone and may allow artificial amplification for prevention of bacterial bone infection in the future

Desmoid tumours are a rare fibroblastic proliferation of monoclonal origin, arising in deep soft-tissues. Histologically, they are characterized by locally aggressive behaviour and an inability to metastasize, and clinically by a heterogeneous and unpredictable course. Desmoid tumours can occur in any anatomical site, but commonly arise in the limbs. Despite their benign nature, they can be extremely disabling and sometimes life-threatening, causing severe pain and functional limitations. Their surgical management is complex and challenging, due to uncertainties surrounding the biological and clinical behaviour, rarity, and limited available literature. Resection has been the first-line approach for patients with a desmoid tumour but, during the last few decades, a shift towards a more conservative approach has occurred, with an initial ‘wait and see’ policy. Many medical and regional forms of treatment are also available for the management of this condition, and others have recently emerged with promising results. However, many areas of controversy remain, and further studies and global collaboration are needed to obtain prospective and randomized data, in order to develop an appropriate shared stepwise approach.

Cite this article: Bone Joint J 2023;105-B(7):729–734.

Listeria monocytogenes is usually thought of as a bacterial pathogen that causes invasive disease including meningitis and bacteraemia in susceptible hosts. It remains a rare cause of bone and joint infection; there is therefore potential for clinical and laboratory delay in diagnosis and for uncertainty over optimal management. We describe our experience of two such cases of L. monocytogenes prosthetic joint infection to highlight key features in clinical presentation and management. Two case reports of L. monocytogenes prosthetic joint infection are described with reference to previous published cases. A 57 year old woman presented with a 10 day history of severe pain and swelling around a left knee prosthesis which had been implanted as bilateral total knee replacements three years previously. She had a background of rheumatoid arthritis, controlled with prednisolone, methotrexate and ritixumab. Cultures from the left knee isolated L. monocytogenes. The patient was commenced on IV amoxicillin and after 4 weeks underwent 1st stage revision including radical debridement and removal of prosthesis. During the procedure an antibiotic-impregnated spacer (gentamycin/clindamycin with additional vancomycin added in house) was inserted. Antibiotic therapy with intravenous amoxicillin was continued for 2 weeks post-procedure and on discharge the patient was converted to oral amoxicillin for a further 8 weeks. The patient went on to have a 2nd stage revision, making a good recovery. An 85 year old woman presented with an 18 month history of discomfort and recurrent abscesses along the wound line of a left hip prosthesis, implanted over 20 years ago. She had a background of osteoarthritis and bullous phemphigoid, previously on steroid treatment. Fluid from the abscess was aspirated and isolated L. monocytogenes. Due to patient preference and frailty, radical revision was not thought a viable management option. Chronic suppressive therapy with oral amoxicillin was therefore instigated; one year on the infection remains well controlled and discomfort in the left hip has improved. L. monocytogenes has previously been infrequently implicated as a pathogen in prosthetic joint infection; however, there are reports of increasing numbers of cases particularly amongst immunosuppressed individuals. With an expanding at-risk population(1), its importance as a cause of prosthetic joint infection is set to rise in the future. Optimal management has not been well studied; it is likely that the best option combines antimicrobial therapy and prosthetic removal if possible

Aims

Surgical limb sparing for knee-bearing paediatric bone sarcoma is considered to have a clinically significant influence on postoperative function due to complications and leg-length discrepancies. However, researchers have not fully evaluated the long-term postoperative functional outcomes. Therefore, in this study, we aimed to elucidate the risk factors and long-term functional prognosis associated with paediatric limb-sparing surgery.