Distal Tibial Metaphysis Research Articles

Adaptations of bone and bone vasculature to muscular stretch training.

The magnitude of bone formation and remodeling is linked to both the magnitude of strain placed on the bone and the perfusion of bone. It was previously reported that an increase in bone perfusion and bone density occurs in the femur of old rats with moderate aerobic exercise training. This study determined the acute and chronic effects of static muscle stretching on bone blood flow and remodeling. Old male Fischer 344 rats were randomized to either a naive or stretch-trained group. Static stretching of ankle flexor muscles was achieved by placement of a dorsiflexion splint on the left ankle for 30min/d, 5d/wk for 4wk. The opposite hindlimb served as a contralateral control (nonstretched) limb. Bone blood flow was assessed during and after acute stretching in naive rats, and at rest and during exercise in stretch-trained rats. Vascular reactivity of the nutrient artery of the proximal tibia was also assessed in stretch-trained rats. MicroCT analysis was used to assess bone volume and micro-architecture of the trabecular bone of both tibias near that growth plate. In naive rats, static stretching increased blood flow to the proximal tibial metaphasis. Blood flow to the proximal tibial metaphysis during treadmill exercise was higher in the stretched limb after 4wk of daily stretching. Daily stretching also increased tibial bone weight and increased total volume in both the proximal and distal tibial metaphyses. In the trabecular bone immediately below the proximal tibial growth plate, total volume and bone volume increased, but bone volume/total volume was unchanged and trabecular connectivity decreased. In contrast, intravascular volume increased in this region of the bone. These data suggest that blood flow to the tibia increases during bouts of static stretching of the hindlimb muscles, and that 4wk of daily muscle stretching leads to bone remodeling and an increase in intravascular volume of the tibial bone.

Clinical Efficacy of Distal Tibial Hounsfield Unit for the Diagnosis of Osteoporosis in Ankle Fractures

Category: Trauma; Ankle Introduction/Purpose: Ankle fracture is one of the most common fractures over the age of 50 years. However, there is a lack of research on osteoporotic ankle fractures compared to other osteoporotic fractures. Recently, some studies have been published that Hounsfield Unit(HU) measuring bone attenuation from CT scan is used for assessing the bone density of not only the hip and spine but also extremities such as the distal radius and proximal humerus. This study aims to evaluate the correlation between HU of distal tibia without ankle fracture and DEXA-BMD and determine the cut-off value of HU for osteoporosis diagnosis. Additionally, this study determines whether the HU of the distal tibia obtained from the preoperative CT scan of ankle fractures helps evaluate patients with osteoporotic ankle fractures. Methods: From June 2016 to August 2020, We retrospectively studied foot and ankle traumatic patients who are postmenopausal women or men over 50 years. They conducted a foot or ankle CT scan containing the axial images of the distal tibia and DEXA- BMD within three months. Patients with open fractures with severe displacement or arthritic change were excluded. The mean HU was obtained from two sequential axial images of the distal tibial metaphysis's largest region of interest (ROI), more than 1cm proximal to the tibial plafond. We divided the patients into Group A without ankle fractures and Group B with distal tibia or fibula fractures in the ankle. The correlation analysis was done between the distal tibial HU and DEXA-BMD. We obtained the cut-off value of the distal tibial HU for osteoporosis using receiver operating characteristic(ROC) curves and compared the results between the two groups. Results: Group A was 38 cases(mean age 69.9), and Group B was 59 (mean age 71.0). There were no statistical differences in patients' characteristics, the mean distal tibial HU, bone density, T-score, and rate of osteoporosis in BMD. All HU values in both groups showed excellent inter- and intra-observer reliability(All intraclass coefficients>0.9). Both groups had significant correlations between the distal tibial HU and DEXA-BMD, especially in the femur neck and L3 spine(r=0.706, 0.622, p< 0.001 in Group A, r=0.625,0.499, p< 0.001 in Group B). The cut-off value for osteoporosis of the distal tibial HU was 153.15(sensitivity 73.9%, specificity 86.7%; area under the curve(AUC) 0.841, 95% CI 0.716-0.965, p< 0.001) in Group A. The cut-off value of Group B was 167.35(sensitivity 66.7%, specificity 75.9%; AUC 0.737, 95% CI 0.610-0.865, p=0.002). Conclusion: The distal tibial HU values on the axial images on the CT showed a significant correlation with the central bone of DEXA-BMD. The distal tibial HU value showed excellent reliability with or without fracture. HU value can be easily obtained using a preoperative ankle CT scan without additional cost & radiation exposure to patients with ankle fractures. Therefore, it can help treat osteoporotic ankle fractures by screening for osteoporosis and deciding the fixation method of surgery.

Ideal entry point and direction of retrograde intramedullary nailing of the tibia

PurposeTo determine the ideal entry point and direction of retrograde intramedullary nailing of the tibia.MethodsThe imaging data of patients with distal tibial fractures from June 2020 to December 2021 in our hospital were collected, and computer-aided design was performed. The relevant data were imported into the software for processing, so as to obtain a distal tibial fracture model and simulate the retrograde intramedullary nail placement in the tibia. The entry points and angles at which the intramedullary nail could be inserted successfully and the fracture could be maintained in good alignment were overlapped and counted to obtain the safe entry range and angle. The center of this safe range is the ideal entry point for retrograde intramedullary nailing of the tibia, and the mean value of the angle is the ideal direction of entry.ResultsThe ideal entry point of the retrograde intramedullary nailing was located at the midpoint of the medial malleolus in the C-arm fluoroscopic anteroposterior (AP) and lateral view. The ideal nail entry direction was located at the anatomic axis of the medial malleolus in the AP position and at the anatomic axis of the distal tibial metaphysis in the lateral position.ConclusionThe ideal point and direction of nail insertion for retrograde tibial intramedullary nailing is a "double midpoint, double axis" approach.

Minimally Invasive Percutaneous Plate Osteosynthesis (MIPO) for Distal Tibial Metaphyseal Fracture: A Better Option

Objective: The objective of this study was to evaluate the radiological and functional outcomes in of treatment of fracture distal tibial metaphysis fixed with pre-contoured anatomical locking compression plate using minimally invasive percutaneous plate osteosynthesis (MIPO) technique. Methods: This was a prospective study conducted at Department of Orthopedic Surgery, Services Hospital Lahore. Total of 58 closed distal tibial metaphyseal fractures (AO classification 43A) included in the study. All patients were operated using anatomical LCP with MIPO technique. The functional outcome was assessed by Tenny & Wiss criteria at 6 weekly intervals with final scoring at 24th week. Functional outcome was graded as excellent, good, fair and poor. Similarly, radiological outcome was also assessed at 6 week intervals using Hammer et al criteria and grade 3 labelled as union. Results: We observed excellent functional outcome in 48 patients (82.6%) and good outcome in 6(10.34%) at last follow-up. Radiological union was achieved in 100% (58) patients at 24th week. The average time of union was 16.5 weeks with a range of 12 to 23 weeks. Total 03 patients (5.17%) developed superficial wound infection which was successfully managed with antibiotic therapy and no surgical site deep infection reported. Conclusion: Results of this study advocate that treatment of distal tibial metaphyseal fractures with LCP by MIPPO technique is an effective modality resulting in low complication rate, high union rates and good functional outcome.

Irreducible Tibial Pilon Fracture Treated with Single-Stage Closed Ilizarov Fixation and Gradual Correction: A Case Report.

A young polytrauma victim of a road traffic accident was diagnosed with comminuted articular fracture of the left distal tibial pilon and open segmental fracture of the fibula. The comminuted distal tibial metaphysis was translocated into the interosseous space and, hence, was irreducible. He underwent single-stage closed Ilizarov device stabilization and gradual postoperative closed reduction to obtain good functional outcome at 9 months. The lung and scapular injuries were treated conservatively. Acute complex irreducible tibial pilon fracture can be treated according to principles of deformity correction with the Ilizarov device.

1423. A Rare Case of Mycobacterium chelonae Septic Joint

Abstract Background Nontuberculous mycobacteria (NTM) are ubiquitous environmental organisms that can cause chronic soft tissue infections and which may affect underlying joints and bone by direct extension. NTM septic joint infections are rare and literature on their management is scarce. Methods Here we describe a case of septic ankle due to M. chelonae, a rapid grower NTM, and review treatment of these infections. Results An 86-year-old man presented to our hospital with complaints of a painful left ankle. Three months prior he noticed a pimple on his left foot after tripping over a lawnmower. The lesion evolved into erythema and painful swelling of the left ankle. Magnetic resonance imaging (MRI) of the left lower extremity revealed a fracture of the distal tibial metaphysis. Turbid joint fluid was aspirated showing 211,450 white blood cells with 97% neutrophils. Patient underwent partial removal of the left tibia with insertion of a drug implant device. Culture results showed acid fast bacilli at day three and the pathology report confirmed atypical mycobacterial infection (Fig 1, 2). Empiric meropenem, linezolid, and azithromycin were initiated until the identification of M. chelonae was obtained. Based on susceptibilities meropenem was discontinued and ciprofloxacin was added. A repeat MRI showed osteomyelitis and small abscesses about the left ankle leading to repeat debridement. Cultures from debridement were negative. Tobramycin IV three times a week was added and ciprofloxacin was discontinued. Patient soon developed acute renal failure, NSTEMI, and lactic acidosis. After a goals of care discussion with patient’s family, antibiotics were discontinued. He passed away soon thereafter. The backbone of NTM treatment usually consists of a macrolide plus 2-3 other agents but susceptibilities can be misleading. Data correlating outcomes of in vitro susceptibility and clinical response is mixed. Consequently, management of NTM infections is often derived from case reports and from the tuberculosis literature. As seen in this patient, effective treatment can be elusive. Neutrophils surround vacuoles filled with acid-fast staining organisms on Fite staining H&E Stain shows pink stained organisms in vacuoles Conclusion NTM infections are often resistant to antimycobacterial therapy and require multi-drug regimens with surgical intervention. Due to this complexity, a multidisciplinary approach is vital to improve outcomes. Disclosures All Authors: No reported disclosures.

Pancreatic involvement in Erdheim-Chester disease: a case report and review of the literature

BackgroundErdheim-Chester disease (ECD) is a rare form of non-Langerhans cell histiocytosis characterized by infiltration of lipid-laden foamy macrophages within different tissues. Clinical manifestations of ECD are highly heterogeneous. Bone lesions are found in 80%-95% of patients, while extraosseous lesions usually involve the cardiovascular system, retroperitoneum, central nervous system (CNS), and skin. Pancreatic involvement in ECD has barely been reported.Case presentationA 29-year-old female initially presented with menoxenia, diabetes insipidus and diabetes mellitus. 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG-PET/CT) revealed hypermetabolic foci in the bilateral frontal lobe, saddle area, and pancreas. A 99mTc-MDP bone scrintigraphy scan revealed symmetrical increased uptake in distal femoral and proximal tibial metaphysis, which was confirmed to be osteosclerosis by high-resolution peripheral quantitative computed tomography. The patient underwent incomplete resection of the sellar mass. Histological examination of biopsies showed histiocytic aggregates, which were positive for S100 and negative for CD1a and CD207 on immunohistochemistry. Enhanced abdominal CT scan showed hypointense nodules within the body and tail of the pancreas. Endoscopic ultrasonography guided fine-needle aspiration (EUS-FNA) found no evidence of malignancy. She was diagnosed with ECD and treated with high-dose IFN-α. Repeated examinations at three-and eight-months post treatment revealed markedly reduction of both intracranial and pancreatic lesions.ConclusionsECD is a rare histiocytic neoplasm that can involve almost every organ, whereas pancreatic involvement has barely been reported to date. Here, we present the rare case of pancreatic lesions in ECD that responded well to interferon-α. We further reviewed reports of pancreatic involvement in histiocytic disorders and concluded the characteristics of such lesions to help diagnosis and treatment, in which these lesions mimicked pancreatic adenocarcinoma and caused unnecessary invasive surgeries.

Medial Malleolar Screw Length to Achieve Thread Purchase in the Dense Bone of the Tibial Epiphyseal Scar Location Based on CT Model

Medial malleolar ankle fractures are one of the most common surgically treated fractures of the ankle joint. Current AO guidelines for medial malleolar fractures recommend 2 partially threaded cancellous screws across the fracture line. For these screws to cross the fracture line, the threads must purchase the distal tibial metaphysis, which is an area of decreased bone density especially in elderly osteoporotic bone. The epiphyseal scar of the tibia is the densest portion of distal metaphysis of the tibia, and it has been determined that bone density decreases significantly further proximal through the tibia. One hundred eighty-three individual weightbearing coronal CT scans were assessed to measure the location of the epiphyseal scar and propose an ideal screw length to purchase this area and remain within the distal most portion of the tibia. In following with this criteria it was determined that a 34 mm ⅓ thread pattern screw and a 38 mm ½ thread pattern screw would suffice for 92.6% and 75.3% of males, respectively. It was determined that a 30 mm ⅓ thread pattern screw and a 32 mm ½ thread pattern screw would suffice for 93.4% and 85.3% of females, respectively. This study proposes optimal screw lengths in a theoretical area of increased bone density that may decrease complications in patients with compromised bone quality.

Bone marrow adipose tissue composition following high-caloric feeding and fasting.

Bone marrow adipose tissue (BMAT) plays a role in systemic energy metabolism and responds to nutritional changes. Chronic starvation as well as visceral adiposity are associated with BMAT accumulation. Two types of BMAT have been described which differ in anatomic location (proximal-regulated-rBMAT vs distal-constitutive-cBMAT) and composition (higher unsaturated lipids of cBMAT compared to rBMAT). To determine the response of BMAT composition to short-term high-caloric feeding and fasting. We hypothesized that high-feeding and caloric restriction would be associated with differences in BMAT composition according to the skeletal site. We examined 23 healthy subjects (13m, 10 f, mean age 33±7years, BMI 26±1.5kg/m2) who were admitted for a 10-day high-caloric stay (caloric intake with goal to achieve 7% weight gain) followed by discharge home for 13-18days to resume normal diet (stabilization period), followed by a 10-day fasting stay (no caloric intake). Subjects underwent single voxel proton MR spectroscopy (1H-MRS) at 3T of the lumbar spine (L4) (rBMAT), the femoral diaphysis and distal tibial metaphysis (cBMAT) to determine BMAT composition (unsaturation index, UI and saturation index, SI). Within group comparisons were performed by the Wilcoxon signed rank test. After the high-calorie visit, SI of L4 increased compared to baseline (0.62±0.27 to 0.70±0.28, p=0.02), and there was a trend of an increase in femoral SI and UI (p≥0.07), while there was no significant change in tibial BMAT (p≥0.13). During the stabilization period, SI of L4 decreased (0.70±0.28 to 0.57±0.21, p<0.0001) and SI of the femoral diaphysis decreased (5.37±2.27 to 5.09±2.43, p=0.03), while there was no significant change in UI or tibial BMAT (p≥0.14). During the fasting period, SI of L4 increased (0.57±0.21 to 0.63±0.30, p=0.03), while there was no change in UI (p=0.7). SI and UI of femoral diaphysis decreased (5.09±2.43 to 4.68±2.15, p=0.03, and 0.62±0.42 to 0.47±0.37, p=0.02, respectively) and UI of the tibial metaphysis decreased (1.48±0.49 to 1.24±0.57, p=0.04). 1H-MRS is able to quantify BMAT composition during short-term nutritional challenges, showing a significant increase in SI of rBMAT during high caloric feeding and a differential response to fasting with an increase in SI of rBMAT and a decrease in SI and UI of femoral cBMAT and decrease in UI of tibial cBMAT.

English

BACKGROUND Fractures of both proximal and distal metaphyses with small distal fragment of tibia are not uncommon. Internal fixation using intramedullary nails alone could lead to misalignment. Using blocking screws (Poller screws) in addition to intramedullary nails would help in narrowing the medullary cavity and decreases the degree of misalignment and chances of displacement. The present study was conducted to evaluate functional and radiological outcome of blocking screws with intramedullary nail in the treatment of proximal and distal metaphyses fractures of tibia with short distal fragment. METHODS A prospective observational study of 34 patients with proximal and distal tibial metaphyses fractures was treated with statically locked intramedullary nailing with supplementary blocking screws. The study was conducted from January 2018 to December 2020 with a maximum follow up of 18 months. Medullary canal diameter was measured at the levels of fracture and isthmus. RESULTS Among the 34 patients, 29 (85.29 %) were males and 05 (14.70 %) were females with a male to female ratio of 5.8 : 1. The mean age was 34.97 ± 3.10 years. The mean healing period was 20 ± 1.45 weeks. 25/34 (73.52 %) of the patients showed Karlstrom and Olerud functional grading score of excellent. The fracture varus/valgus alignment was 1.9 ± 0.3 degrees. The mean antecurvatum/recurvatum alignment was 0.3 degrees. CONCLUSIONS Blocking screws act as reduction tools, help in reducing the medullary lumen of distal metaphyses and prevent failures in initial reduction. They extend the indication of intramedullary nailing to the distal segment of tibia and minimize the misalignment in terms of varus /valgus and/or antecurvatum/recurvatum. KEYWORDS Tibia, Intramedullary, Blocking Screws, Internal Fixation and Misalignment

Outcome of percutaneous locked plating of extra-articular distal tibial metaphyseal fractures

Introduction: Management of fractures involving the distal tibial metaphysis is one of the most challenging and controversial issue due to poor soft tissue envelop. Multiple different fixation modalities are available with different outcome. Percutaneous plating of the distal tibia fracture is gaining more popularity due to minimal interruption of the fracture biology and favorable functional and radiological outcomes. Purpose: To evaluate the functional and radiological outcome of management of distal tibia extra articular metaphyseal fractures using locked plates with Minimally Invasive Plate Osteosynthesis (MIPO) technique. Methods: Twenty four patients with extra- articular distal tibia metaphyseal fractures were operated with locked compression plates using MIPO technique. They were followed up at regular intervals. Functional and radiological results were evaluated at the end of follow up. Results: All fractures united at average time of 12.21 weeks (range; 8-20 weeks). Postoperatively, two patients developed deep infection and two patients developed malunion. Mean AOFAS score was excellent 90.6 points (range: 52-100) at last follow up. Conclusion: MIPO technique using distal tibia locked plating is an effective procedure for fixation of distal tibia extra-articular metaphyseal fractures. It provides near anatomical fracture reduction with sufficient stability and preservation of the blood supply to the fracture fragments. It provides excellent functional results with acceptable rate of complications.

Study of distal tibial extra-articular fractures fixed with locking compression plate using MIPO technique

Background: Fractures of distal tibial metaphysis present a management challenge because of their inherent instability, scarcity of soft tissue, subcutaneous nature and poor vascularity of bone. MIPO techniques are advantageous because of limited soft tissue strapping, maintenance of the osteogenic fracture haematoma without interrupting vascular supply to the individual fracture fragments. Materials and Methods: This is a study of 20 patients of closed extra articular distal tibial fractures treated with anatomical LCP applied on antero-medial surface of lower end tibia with MIPO technique. Age was ranging from 20 to 60 yrs. 14 male and 6 female patients were there. 7 patients were having fibula fracture at same level of tibia fracture, they were fixed with DCP/ 1/3 tubular plate before fixing tibia. Results: AO/OTA type 43 A1 fractures were there in 15 patients. 4 pts. were having 43 A2 and one pt. was having 43 A3 type fracture. Average operation time was 80 mins. Average union time was 18.5 weeks. One pt. was having delayed union, one having superficial skin infection, one having 6* varus angulation and one having malleolar skin irritation. No pts. required second surgery of bone grafting. No implant failure. Conclusion: MIPO with LCP is a reliable and effective method of treatment for the distal tibial extra-articular fractures, preserving most of the osseous vascularity and fracture haematoma and thus providing a more biological repair. Using indirect reduction technique and small incision is technically demanding. Keywords: Anatomical LCP, Distal tibial fractures, MIPO.

Medial Column Support in Pilon Fractures Using Percutaneous Intramedullary Large Fragment Fixation.

Pilon fractures are complex injuries to the tibial plafond requiring stable fixation in the setting of effective soft tissue management, particularly in high-energy injuries, open fractures, or in geriatric individuals. Medial column support of the distal tibial metaphysis is often an essential component when applying balanced fixation. However, the biologic implications of multiple surgical approaches in the setting of damaged tissue, devitalized bone, or significant bone loss may contribute to increased complications. Percutaneous intramedullary large fragment screws offer both stability and a soft tissue-friendly approach for stabilizing the medial column. Here, we present our technique and indications for medial column support in pilon fractures using percutaneous large fragment fixation, along with our early clinical experience in a case series of 7 patients. At minimum 6-month follow-up, all patients healed their injuries with maintained alignment and without complications or further reoperation. Medial column support with percutaneous large fragment fixation in pilon fractures is a viable option to provide mechanical stability while effectively managing tenuous soft tissue envelopes.

Solitary osteochondroma from interosseous border of distal tibia

We present a 24-year-old man with an impending fracture of distal fibula, due to a solitary sessile osteochondroma arising from the lateral border of distal tibial metaphysis on the right side. He presented with a swelling on the anterolateral aspect of distal tibia causing mechanical limitation of dorsiflexion of ankle joint and with occasional mild pain. Imaging studies revealed a solitary sessile osteochondroma, abutting the distal epiphysis of tibia, and deforming the fibula. The swelling was excised and the histopathology was suggestive of osteochondroma.

Management of distal tibial metaphyseal fracture by expert tibial nail using suprapatellar approach

Background: Distal tibial metaphyseal fractures are common lower limb injuries and results in extensive musculoskeletal damage due to paucity of soft tissue coverage. Fixation methods include open reduction and internal fixation (ORIF) with plates, minimally invasive percutaneous plate osteosynthesis (MIPPO) and intrameduallary nailing. Extensive exposure for ORIF leads to wound complications,nonunion and infection. Intramedullary nailing is the preferred for diaphyseal tibial fracture however conventional nailing is less suited for distal tibial metaphysis due to diameter mismatch between the nail and the bone leading to very little nail effect and impaired stability. Expert tibial nail with multiplanar locking options at the proximal and distal end allows for secure stabilization of the metaphyseal fragments. Infrapatellar approach is traditionally used for tibial nailing however suprapatellar approach is emerging as an alternative as semi-extended positioning makes it technically easier to nail the proximal and distal fractures. Materials and Methods: This is a prospective study conducted from February 2019 to February 2020. 14 patients fulfilling the inclusion criteria underwent intramedullary nailing using the suprapatellar approach. The functional outcomes were measured at 6 months using the Lysholm knee score and the SF-36 physical and mental score. The obtained data was analyzed using SPSSv16. Result: The average time of fracture union was 17.8 weeks. The mean SF-36 physical and mental score were 42.4 and 44.5 respectively. The average Lysholm score was 84. The mean arc of motion in the involved knee was 110ᵒ. Secondary procedure in the form of dynamization was done in 2 cases. Anterior knee pain was observed in 3 patients.Conclusion: Expert tibial nailing using suprapatellar approach appears to be a suitable fixation method for distal tibial metaphyseal injuries as it provides good functional and clinical outcome at the same time minimizing the violation of delicate soft tissue structures.

An Incidental Finding Of Post Traumatic Diaphyseal Tibiofibular Synostosis – A Case Report

Tibio-fibular synostosis is a rare, limb malformation characterized by fusion of the proximal or distal tibial and fibular metaphysis and/or diaphysis. The present case was an incidental finding in the Osteology sec-tion of the Anatomy Museum. We report a rare case of tibiofibular synostosis, reported occasionally in the Indi-an population. The left tibia and fibula were malunited by the synostotic segment of bone at the junction of the middle and lower 1/3rd of the bones. It is imperative for orthopedic surgeons to follow up postoperative leg cases radiologically and evaluate cases with leg and ankle pain keeping this entity in mind. Keywords: Tibiofibular synostosis, Post traumatic ossification, Diaphysis

P49 An unusual cause of transient migratory bone oedema: fibroblast growth factor-23 secreting a mesenchymal tumour

Abstract Background Fibroblast growth factor-23 (FGF-23) is a phosphate regulator primarily expressed by osteocytes. Excess FGF-23 leads to decreased hydroxylation of 25-hydroxyvitamin D and poor renal phosphate reabsorption. This leads to hypophosphatemia and represents a rare cause of osteomalacia, resulting in bone oedema and stress fractures. Methods A 57-year-old man with known skin psoriasis presented with a two-year history of left foot and ankle pain. On examination, he had chronic dactylitis of the big toe and extra-articular features included skin psoriasis on the scalp, elbows, knees, and nail pitting. Serum inflammatory markers were normal, and autoimmune screens for RF, anti-CCP and HLA-B27 were negative. Bilateral foot and ankle X-rays showed no bony abnormality. This was diagnosed as likely psoriatic arthritis and MRI showed talar bone oedema, felt to be related to inflammatory arthritis. Symptoms settled well on non-steroidal anti-inflammatories. However, he presented with focal distal tibial swelling and pain, two months later. There was no history of trauma, Repeat MRI2 showed proximal migration of bone oedema with stress fractures of the left posterior talus and distal tibial metaphysis. Bloods tests showed low phosphate, elevated PTH, normal adjusted calcium, raised ALP and low 25-OH vitamin D. DEXA scan confirmed osteoporosis of the hip. The patient was commenced on bisphosphonate with 25-hydroxyvitamin D and phosphate supplementation. Despite this, the patient continued to have migratory joint pain affecting the ankle, hip and sacroiliac joints. Methotrexate was started for psoriasis and whilst his skin improved, his pain remained and further MRI showed left talar and right neck of femur insufficiency fractures. Results Although taking vitamin D3 supplementation, he remained hypophosphateamic 0.5mmol/L. Myeloma screen and PET FDG were normal. However, he was noted to have an increased fractional urinary phosphate excretion indicating poor renal phosphate reabsorption. One possible cause of this is elevated FGF-23, which was confirmed with FGF-23 assay (include levels and normal range). The patient underwent PET Ga-DOTATE imaging, utilising a tracer specific for somatostatin receptors found on neuroendocrine tumours. This showed a T9 pedicle lesion and a CT-guided biopsy confirmed a mesenchymal tumour as the cause of FGF-23 secretion, resulting in TBMO and insufficiency fractures. The patient has become asymptomatic on calcitriol and phosphate supplementation. He is now being considered for radiofrequency ablation therapy. Conclusion This case illustrates the need for a thorough investigation of symptomatic, treatment-refractory hypophosphataemia. Although mild hypophosphatemia could indicate adult-onset rickets, rarer causes such as FGF-23 secreting tumours should be considered. These tumours are notoriously difficult to locate; Ga-DOTATE PET is probably superior to other imaging modalities including FDG-PET in isolating mesenchymal tumours. Disclosures K. Fisher None. S. Melath None. S. Patel None.

P41 Searching high and low for a cause of transient migratory bone oedema: fibroblast growth factor-23 secreting mesenchymal tumour

Abstract Background Fibroblast Ggrowth factor-23 (FGF-23) is a phosphate regulator primarily expressed by osteocytes. Excess FGF-23 leads to decreased hydroxylation of 25-hydroxyvitamin D and poor renal phosphate reabsorption. This leads to hypophosphataemia and represents a rare cause of osteomalacia, resulting in bone oedema and stress fractures. Methods A 57-year-old man with known skin psoriasis presented with a two-year history of left foot and ankle pain. On examination, he had chronic dactylitis of the left, big toe associated with skin psoriasis and nail pitting. Serum inflammatory markers were normal, and autoimmune screens for RF, anti-CCP and HLA-B27 were negative. Bilateral foot and ankle X-rays showed no bony abnormality. This was diagnosed as likely psoriatic arthritis and MRI showed talar bone oedema, felt to be related to the inflammatory arthritis. Symptoms settled well on non-steroidal anti-inflammatories. However, he presented two months later with focal distal tibial pain and swelling. There was no history of trauma. Repeat MRI showed proximal migration of bone oedema with stress fractures of the left posterior talus and distal tibial metaphysis. Results Blood tests showed low phosphate, elevated PTH, normal adjusted calcium, raised ALP and low 25-hydroxyvitamin D. DEXA scan confirmed osteoporosis of the hip. The patient was commenced on intravenous three-monthly pamidronate and colecalciferol (vitamin D3) supplements. Despite this, the patient continued to have migratory joint pain affecting the ankle, hip and sacroiliac joints. Methotrexate was prescribed to improve his psoriasis, but whilst his skin improved his legs remained painful. A repeat MRI showed new insufficiency fractures to the left talus and right neck of femur. Although taking colecalciferol supplementation, his serum phosphate remained low (0.5mmol/L). On further investigation, Myeloma screen and FDG PET were normal but he was noted to have an increased fractional urinary phosphate excretion indicating poor renal phosphate reabsorption. Serum FGF-23 assay was elevated at 131 mIU/L (normal &amp;lt;100mIU/L). The patient underwent 68-Gallium DOTATATE PET imaging, utilising a tracer specific for somatostatin receptors found on neuroendocrine tumours, which showed a T9 pedicle lesion. CT-guided biopsy confirmed a mesenchymal tumour as the cause of FGF-23 secretion, resulting in transient bone marrow oedema and insufficiency fractures. The patient has become asymptomatic on calcitriol (1,25-dihydroxyvitamin D) and phosphate supplementation, and is being considered for radiofrequency ablation therapy. Conclusion This case illustrates the need for thorough investigation of symptomatic, treatment-refractory hypophosphataemia. Although mild hypophosphatemia could indicate adult onset rickets, rarer causes such as FGF-23 secreting tumours should be considered. These tumours are notoriously difficult to locate; 68-Gallium DOTATATE PET may offer superior specificity to other imaging modalities, including FDG-PET, in detecting these mesenchymal tumours. FGF-23 decreases hydroxylation of vitamin D3 and renal phosphate reabsorption, and calcitriol alongside phosphate supplementation is advisable for symptomatic management until definitive treatment. Disclosures K. Fisher None. S. Melath None. S. Patel None.

Consequences in plating of fibula of distal metaphyseal tibial and fibular fractures: A teaching hospital based study in North India

The tibia is exposed to frequent injury. Distal tibial metaphyseal fractures are often the result of high-energy trauma, usually associated with distal fibular fractures. The presence of the ankle joint allows rotatory deformity after fracture, and care should be taken during reduction to correct such deformity. Fixation of fibular fractures in distal tibial metaphyseal fractures is controversial, although fixation of the fibular fracture by a plate and screws partially stabilizes comminuted fractures of the distal tibial shaft or metaphysis and considered in distal tibial fractures treated with intramedullary fixation to prevent valgus deformity even there is increased potential for delaying the tibial fracture healing. Objectives: The purpose of this study was to compare the functional and radiological outcome of fractures of distal third tibia and fibula treated by interlocking nail of tibia with fibular plating and without fibular plating. Material and Methods: A total of 24 patients who had fractures of lower third tibia and fibula are included in this study. 24 patients were divided into two groups A and B (12 patients in each group) based on fibular fixation. Results: Functional results were evaluated based on classification system for result of treatment by Johner and Wruhs criteria. Functional Outcome according to Johner and Wruhs criteria based on clinical rotational alignment, radiological valgus angulation and ankle range of movements, in group A 7 patients (58%) had good results and 5 patients (42%) had fair results. In group B 8 patients (67%) had good results and 4 patients (33%) had fair results (p=1.00 statistically not significant).Conclusion: Based on the results of the study, it was confirmed that fixation of fibula first, along with interlocking nailing of the tibia maintains limb length and decreases the malalignment and malrotation of the tibia in distal third fractures of tibia and fibula as compared with only interlocking nailing of tibia in distal third fractures of tibia and fibula.

Composite external fixation for children with fracture of lower extremity metaphysis

Objective To evaluate the composite external fixation in the treatment of children with fracture of lower extremity metaphysis. Methods A retrospective analysis was conducted of the 42 children with fracture of lower extremity metaphysis who had been admitted to Zhengda Shaoyang Orthopaedic Hospital between September 2016 and September 2018. They were 24 boys and 18 girls, aged from 3 to 14 years (mean, 8.3 years). Open injury occurred in 10 cases, with type Ⅰ in 2, type Ⅱ in 7 and type Ⅲ in one according to the Gustilo-Anderson classification, and closed injury in the other 32 ones. The fracture happened at distal femur in 12, at proximal tibia in 9 and at distal tibia in 21 cases. All the patients were fixated with composite external brackets. Fracture healing, functional recovery of the knee and ankle joints, and complications were recorded. Results All the 42 patients were followed up for 12 to 18 months (mean, 15.8 months). All fractures healed well by the first intention with no malunion or no alignment change on the full length X-ray films of both lower limbs. Irritant growth within 1.5 cm was observed in 2 cases. No loosening occurred in the external fixation which was removed 3 to 5 months after surgery (mean, 3.8 months). Functional recovery of the knee and ankle joints was good at the last follow-up. For the patients with distal femoral metaphysis fracture, the knee function by the Merchan scoring was excellent in 3 cases, good in 7 cases, fair in one and poor in one; for the patients with proximal tibial metaphysis fracture, the knee function by the Merchan scoring was excellent in 3, good in 4 and fair in 2 cases; for the patients with distal tibial metaphysis fracture, the ankle function by the Kofoed scoring was excellent in 11, good in 7 and fair in 3 cases, giving an excellent and good rate of 83.3%. Of a total of 228 needle channels in the 42 patients, 58 were infected mildly or moderately, giving an infection rate of 25.4%. All the infections responded to active dressing change. Conclusion The composite external fixation brackets are a good choice for the treatment of children with fracture of lower extremity metaphysis, because they are easy in manipulation and stable in configuration, and can reduce the iatrogenic injury to the epiphyseal plate, spare cross-articular fixation and allow early functional exercise. Key words: Lower extremity; Fractures, bone; Fracture fixation; External fixator; Child