Adamantinoma is a rare low-grade malignant epithelial bone tumour. We report a case of an expansile, osteolytic mid-diaphyseal tibial lesion found in a 12 year-old girl. An initial histological diagnosis of basaloid-type adamantinoma was made. Following excision, further histology demonstrated basaloid cells and acellular matrix focally surrounded by osteoclast giant cells with calcium deposits, features consistent with pilomatrixoma. Several histological variants of adamantinoma have been documented; this case details a previously unreported histological adamantinoma variant – pilomatrixoma-adaminatinoma

Adamantinoma is a primary low-grade, malignant bone tumor that is predominantly located in the mid-portion of the tibia. The aetiology of the tumor is still a matter of debate. Histologically, classic adamantinoma is a biphasic tumor characterized by epithelial and osteofibrous components that may be intermingled with each other in various proportions and differentiating patterns. We report here a particular morphologic variant of adamantinoma characterised by the loss of classic epithelial differentiation. A 17 year-old teenager presented with a long history of a tumor in the left leg. Explorations revealed an osteolytic lesion of the middle shaft of the left tibia with a huge mass invading soft tissues. An intra medullar bone lesion with benign appearance was observed in the right tibia. CT of the chest revealed lung metastases. Histologically, we observed in the left side a pattern of spinde-celled high grade sarcoma without any evident differentiation. Spindle-shaped tumor cells express cytokeratins and vimentin. Ultrasturctural study showed tonofibrils and desmosomes and was helpful to recognize the epithelial nature of the tumour. The diagnosis of dedifferentiated adamantinoma was retained. In the right tibia biopsy revealed fibrous dysplasia. Amputation above the knee was performed followed by chemotherapy. One year later, the patient is still alive with multiple lung metastases. In our study, we discussed the clinico-pathologic features of this particular pattern of adamantinoma as well as its association with fiobrous dysplasia in this case. A review of literature was done

Aims: Purpose of this study was to obtain long term follow-up in patients with Osteofibrous Dysplasia (OFD), in order to investigate natural history of the disease, late results of treatment, and potential risk of Adaman-tinoma development in this setting. Methods: A retrospective study of 48 patients with histologically proven OFD observed at our Institution between 1900 and 1997 was undertaken. Clinico-pathologic features of all cases were reviewed and found consistent with OFD. A clinical status update and current radiographs were obtained in all patients. A subgroup of 21 patients with minimum follow-up of 20 years (21 to 44 years, average 27) was analysed for functional result and adamantinoma development. Functional result according to MTS-ISOLS score correlated with surgical aggressiveness. Results: Best results were observed in patients that received a single biopsy or curettage; worse results were seen after multiple resections or osteotomies and associated with complications as infection or compartment syndrome. No patients had current symptoms or significant symptoms changes nor physical findings, radiographic clues or subsequent radiographic changes suggesting adamantinoma development. Conclusions: OFD is a benign condition; the natural history of the disease has minimal consequences in the adult life. Surgical treatment is usually not necessary and may actually worsen the result because of the potential for severe complications. The relationship with adamantinoma remains unclear, follow-up is suggested

Adamantinoma are rare, low grade malignant, bone tumors, making up only 0.1–0.48 percent of primary malignant bone tumors. They occur predominantly in the long bones, especially the tibia. Histogenetically it is thought that it originates from embryological displacement of basal epithelium of the skin, although other hypotheses have been proposed. Clinically most patients present with swelling and possible bending of the tibia, painful or painless. It's often noticed in an earlier stadium, but symptoms are non-specific and have a slow progressive character. Median patient age is 25 to 35 years, with a range from two to 86 years. It is slightly more common in men than woman, with a ratio of 5:4. Occurrence in children is even rarer. A study by Van Rijn et al. finds only 119 references, and presents six more cases. Treatment is the same. An MRI-scan should be performed to check for metastasis, loco regional staging and for operative planning. Operative excision and reconstruction is necessary to prevent metastasis and maintain load bearing capacity. Generally these resections and reconstructions are done without objective measurements. The surgeon uses a rule of thumb, like a sculptor, or ruler approach to recreate the excised bone, either with allo- or autograft materials. An optimal fit, i.e. a minimal space between tibia and graft, is not always achieved, possibly resulting in pathological fractures. This risk of pathological fractures lengthens recovery time. The fractures elongate hospitalization time and recovery time and are a heavy burden to patients. Computer assisted surgery (CAS) systems, used for example in prosthesis placement, offer objective measurements in 3d space of hard structures with high accuracy. These can be used to produce an accurate copy of the resected bone. If the reconstruction accurately fits the bone defect that's left after the resection, it's likely that the occurrence of pathological fractures decreases. An adamantinoma in the tibia of a 12 year old boy was treated. Surgery consisted of hemicortical resection and inlay allograft reconstruction. The software used was the Orthomap navigation software (Stryker). A donor bone was supplied with help from the bone bank. The technical approach to the reconstruction was the planning of resection planes around the tumor. As the CT scale for both the patient and allograft bone is the same, the resection planes in the patient navigation setup could be copied to the allograft creation setup. Normal CAS setup was performed after first incision, with a tracker attached to the tibia. It was planned that a navigated bone saw would be used for the cutting. The tracker was attached to the saw with a new attachment, and calibrated in the universal calibration tool. During the surgery the oscillating saw proved to be impossible to navigate. The instrument calibration module was not able to accurately registered the saw, this despite accurate registrations in pre-operative testing. The CAS system was used however for accurately determining the saw planes. The planes were traced with the pointer tool. Then a non-navigated saw was used to perform both trapezoid shaped resections. A similar CAS setup was performed on the donor bone. The reconstruction was a good fit. The skin was closed in layers. Post-operative x-ray control was performed. Operation time was just over two hours. Currently the follow-up time is five months. There have been no complications and the control x-rays show good allograft ingrowth. While the original operation plan couldn't be performed the principle of computer assisted reconstruction has its merits. This was a proof of concept. The navigation was accurate to less than 1 mm, and the trapezoid resection shape guarantees a good fit. However the method of resection of the drawn planes by non-navigated bone saw was not accurate enough, because of the saw oscillations. There was improvement in operation time. With more accurate means of resection, as for example a computer controlled laser or water-jet, this type of reconstruction could have other very interesting applications

Introduction: The purpose of this study is to demonstrate that definitive surgery (extraperiosteal excision) is required in patients with osteofibrous dysplasia (OFD) due to the risk of recurrence and co-existent adamantinoma. The possible link with adamantinoma is controversial with some authors believing that they are part of one histological process. This therefore provides difficulty in recommending treatment options. Methods: Using our database 22 cases of OFD were identified. Management was diverse. Results: Definitive (extraperiosteal) surgery, in the majority of our patients, was localized excision for small lesions (less than 50% of the bony circumference) and segmental excision followed by reconstructive surgery for more extensive ones. Seven patients had a “shark-bite” excision and a further seven were treated with fibula autografting. Of the latter group, one required further excision and bone transport due to recurrence of OFD. Five underwent bone transport & distraction osteogenesis and one had a proximal tibial replacement. Nine initially underwent curettage, but eight recurred. No recurrences occurred following localized extraperiosteal excisions and bone transport. There were three confirmed cases of adamantinoma. Discussion: In view of the risk of association of OFD with adamantinoma, and to some extent the continuous morbidity of OFD if left untreated, we believe that radical extraperiosteal excision is indicated in most if not all cases of OFD

The purpose of this study is to demonstrate that definitive surgery (extraperiosteal excision) is required in patients with osteofibrous dysplasia (OFD) due to the risk of recurrence and co-existent adamantinoma. OFD is an unusual childhood condition, which almost exclusively affects the tibia. It is thought to follow a slowly progressive course and to stabilise after skeletal maturity. The possible link with adamantinoma is controversial with some authors believing that they are part of one histological process. This therefore provides difficulty in recommending treatment options. A retrospective review of OFD was conducted. Using the Stanmore Bone Tumour Unit database 22 cases were identified who were initially diagnosed with OFD or were diagnosed on final histology. All cases were tibial except one lesion in the ulna and one in the fibula. Management was diverse depending on the severity of symptoms and the extent of the lesions encountered. Definitive (extraperiosteal) surgery in the majority of our patients was localized excision for small lesions (less than 50% of the bony circumference) and segmental excision followed by reconstructive surgery for more extensive ones. Seven patients had a sharkbite excision and a further seven were treated with fibula autografting. Of the latter group, one required further excision and bone transport due to recurrence of OFD. An additional five underwent bone transport & distraction osteogenesis using the Ilizarov technique and one had a proximal tibial replacement. Nine initially underwent curettage, but eight recurred (recurrence rate 88.9%). No recurrences occurred following localized extraperiosteal excisions and bone transport. There were three confirmed cases of adamantinoma. In view of the risk of association of OFD with adamantinoma, and to some extent the continuous morbidity of OFD if left untreated, we believe that radical extraperiosteal excision is indicated in most if not all cases of OFD

Introduction and Aim: The purpose of this study is to demonstrate that definitive surgery (extraperiosteal excision) is required in patients with osteofibrous dysplasia (OFD) due to the risk of recurrence and co-existent adamantinoma. OFD is an unusual childhood condition, which almost exclusively affects the tibia. It is thought to follow a slowly progressive course and to stabilise after skeletal maturity. The possible link with adamantinoma is controversial, with some authors believing that they are part of one histological process. This therefore provides difficulty in recommending treatment options. Method and Results: A retrospective review of OFD was conducted. Using the Stanmore Bone Tumor Unit database, 22 cases were identified who were initially diagnosed with OFD or were diagnosed on final histology. All cases were tibial except one lesion in the ulna and one in the fibula. Management was diverse, depending on the severity of symptoms and the extent of the lesions encountered. Definitive (extraperiosteal) surgery in the majority of our patients was localised excision for small lesions (less than 50% of the bony circumference) and segmental excision followed by reconstructive surgery for more extensive ones. Seven patients had a ‘sharkbite’ excision and a further seven were treated with fibula autografting. Of the latter group, one required further excision and bone transport due to recurrence of OFD. An additional five underwent bone transport and distraction osteogenesis using the Ilizarov technique and one had a proximal tibial replacement. Nine initially underwent curettage, but eight recurred (recurrence rate 88.9%). No recurrences occurred following localised extraperiosteal excisions and bone transport. There were three confirmed cases of adamantinoma. Conclusion: In view of the risk of association of OFD with adamantinoma, and to some extent the continuous morbidity of OFD if left untreated, we believe that radical extraperiosteal excision is indicated in most if not all cases of OFD

This case highlights the close association between osteo-fibrous dysplasia (OFD) and adamantinoma, drawing attention to the role for more radical treatment options when treating OFD. We discuss the advancements in joint-sparing endoprostheses using bicortical fixation. Finally we describe a unique biomedical design allowing for manufacture of an end cap to allow amputation through a custom made joint-sparing proximal tibial replacement as opposed to an above knee amputation. A 37 year old presented 7 years ago having sustained a pathological fracture of her tibia. Subsequent biopsy revealed OFD, curettage with bone graft was performed. She later developed recurrence, two percutaneous biopsies confirmed OFD. 6 years following her initial diagnosis she was referred to RNOH with further recurrence, a biopsy at this stage revealed a de-differentiated adamantinoma. A joint-sparing proximal tibial replacement was performed and adjuvant chemotherapy administered, she remained well for one year. Recurrence was noted at the distal bone-prosthesis interface, histology revealed a high grade dedifferentiated osteosarcoma, limb preservation was not deemed possible and an amputation was performed through the prosthesis. The proximal tibial device was uncoupled leaving a residual 7 cms insitu, a small custom made end cap was attached to the remaining prosthesis and a myocutaneous flap fashioned over it, this ultimately enabled the patient to mobilise well with a below–knee orthotic device. This case highlights the need for more radical surgery when treating cases of OFD and the relationship between OFD and adamantinoma. It also introduces a joint-sparing proximal tibial device for use in proximal tibial tumours that do not invade the proximal tibial metaphysis. The biomechanical design solution has given us the unique option of preserving the knee joint allowing the patient a below knee amputation whereas previously an above knee amputation would have been performed thereby significantly reducing her functional outcome

A nine-year-old girl presented with a four-year history of progressive bowing of the left tibia. She had been seen in our clinic three and four years earlier, when no treatment was advised. She had been complaining of mild pain in the left leg for one month but was otherwise not very perturbed about her deformed leg. Examination showed bowing of the left tibia, no leg length discrepancy, no limp, and a normal left knee and ankle. Radiological examination showed features of osteo-fibrous dysplasia of the left tibia, with eccentric expansion of the cortex, intracortical osteolysis, marginal sclerosis encroaching on the medulla and diffuse lesional calcification. No other bones were involved. Because of the progressive bowing of the tibia and the mild pain, the recommended loose observation of the patient was abandoned. Daily treatment with 30 mg IVI pamidronate for three days resolved the pain. One month after the latest presentation the lesion was biopsied. Histological examination confirmed the diagnosis of osteofibrous dysplasia of the tibia. There was no evidence of adamantinoma. The literature on this rare bone lesion in childhood supports the use of open biopsy if the deformity becomes painful, the bowing is progressive and the patient presents after the age of nine years. Important differential diagnoses include fibrous dysplasia and adamantinoma

The management of pathological fractures in children remains controversial. The indications for surgical treatment are unclear and the need for histological diagnosis before or after definitive treatment is not clearly defined. We reviewed retrospectively the records of all patients under the age of 16 years who presented over the past 7 years with a fracture as the first manifestation of bone pathology. There were 26 patients (19 boys and 7 girls) of an average age of 12 years and 2 months (range 4.1–15.8 years). There were 9 cases of fracture through a simple bone cyst, 6 in the humerus and 3 in the femur. In all cases the fracture was treated conservatively initially. Subsequent management included needle biopsy in all, followed by bone marrow injection under the same anaesthetic. The patients suffered a refracture and were treated with flexible intra-medullary nail fixation. There were 5 cases of fibrous dysplasia, of which 2 in the femur, 2 in the tibia and one in the proximal radius. Histological diagnosis was obtained in all cases prior to definitive treatment. This included a locked intra-medullary nail in one patient and flexible nailing in another two. The remaining two patients are still under observation. There were 2 patients with giant cell tumour, 3 patients with aneurysmal bone cyst and one patient with chondroblastoma. Histological diagnosis preceded treatment with curettage and grafting in all these cases. There were 6 patients with malignant primary bone tumour, 1 adamantinoma, 2 osteosarcoma, and 3 with Ewings Sarcoma. The 3 patients with Ewing’s sarcoma involved the femur. One had extensive local disease and early intra-medullary nailing was performed for palliative reasons. The second patient was treated conservatively initially. Definitive surgery was performed after fracture healing and included segmental resection and vascularised fibular graft. The third patient was initially treated elsewhere. She was thought to have a benign lesion and internal fixation with a screw/plate device was performed. Histology from intra-operative specimens confirmed Ewing’s sarcoma. Definitive surgery required extensive resection and prosthetic replacement. The 2 patients with osteosarcoma had fracture of proximal humerus and distal femur. The former was treated by forequarter amputation as there was tumour involvement of brachial plexus and remains AWND at 7 years. The latter had resection and EPR of the distal femur. One patient with adamantinoma underwent segmental resection and reconstruction with VFFG. We recommend that primary fixation of pathological fractures should be avoided until histological diagnosis is obtained. However, if radiographic appearances are reassuringly benign, biopsy can be delayed until conservative fracture management is completed. Definitive treatment of benign lesions with protective intramedullary nailing or curettage and grafting can follow frozen section under the same anaesthetic

Background: Amputation of the distal fibula for malignant tumors is accepted practice. Few studies have reported limb salvage surgery for malignant tumors of the distal fibula. After distal fibulectomy, the main concerns are local recurrence of the tumor and ankle instability and deformity related to total resection of the lateral malleolus. Our objective was to analyze the oncologic and functional outcome of lateral malleolus en bloc resection for malignant tumors of the distal fibula, with special attention to operative techniques, reconstruction methods, and postoperative complications. Methods: The authors identified ten patients who had malignant tumors of the distal fibula requiring total resection of the lateral malleolus. The patients’ medical records, operative reports, radiographs, and the histologic specimens were reviewed. There were four children (mean age, 7.5 years) and six adults (mean age, 42.16 years). The distal metaphysis was involved in seven patients and the epiphysis in three. There were four osteosarcomas, three chondrosarcomas, two Ewing sarcomas, and one adamantinoma. The most common symptoms at presentation were a palpable mass in nine patients, ankle pain in six, and pathologic fracture in one. The mean duration of symptoms before diagnosis and treatment was nineteen months. All patients had operative treatment; two patients with osteosarcoma had perioperative chemotherapy and one patient with Ewing sarcoma had radiotherapy and chemotherapy and another patient with Ewing sarcoma had chemotherapy only. Two types of “en bloc” resection of the distal fibula were performed. Wide (type II) extra-articular resection was performed in seven patients. Marginal (type I) intra-articular resection of the distal fibula was performed in three patients. After resection, a primary ankle arthrodesis was performed in four adults and postoperative bracing without any reconstruction in four children and two adults. Results: Within a mean follow-up time of 14.4 years (range, three to thirty years), tumor recurred locally in two patients after a marginal type I resection of a chondrosarcoma, and in one after a type II wide extra-articular resection of an osteosarcoma. All ten patients were disease-free at latest follow-up examination. Six patients had reoperation. A below-knee amputation was performed in three patients for chronic osteomyelitis, for local recurrence of chondrosarcoma, and for a late adamantinoma of the tibia. One patient had further soft tissue and bone reconstructive surgery for lateral talus subluxation and cavovarus deformity. Another patient required ankle arthrodesis for recurrent ankle instability and ankle joint degenerative changes. One patient had wide re-resection for local recurrence of an osteosarcoma. All ten patients were ambulatory at latest follow-up evaluation. Four adult patients who underwent primary arthrodesis and one child who had no initial reconstruction and had late ankle arthrodesis had a satisfactory outcome, with an ISOLS functional score of 27.6 (92%). Two adolescents who had postoperative bracing without any soft tissue reconstruction had an ISOLS functional score of 24 (80%) with no ankle pain and satisfactory function; they used an ankle-foot orthosis during sports activities. Three patients who subsequently required below-knee amputation used a below-knee prosthesis for ambulation. Conclusions: Limb salvage surgery for high-grade malignant tumors of the distal fibula can be achieved by wide extra-articular resection. For low-grade malignant tumors or high-grade tumors responding to adjuvant therapy, a more conservative marginal intra-articular resection may be adequate. Primary arthrodesis is indicated in adults after wide extra-articular resection. In children, repair of the lateral soft tissues and reconstruction of the tibiofibular mortise is necessary after tumor resection to avoid late ankle deformity or instability

Aims

The proximal tibia (PT) is the anatomical site most frequently affected by primary bone tumours after the distal femur. Reconstruction of the PT remains challenging because of the poor soft-tissue cover and the need to reconstruct the extensor mechanism. Reconstructive techniques include implantation of massive endoprosthesis (megaprosthesis), osteoarticular allografts (OAs), or allograft-prosthesis composites (APCs).

A systematic literature review of distraction osteogenesis (DO) for the primary reconstruction of bone defects following resection of primary malignant tumours of long bones (PMTLB) is presented. Fewer than 50 cases were identified. Most reports relate to benign tumours or secondary reconstructive procedures. The outcomes of our own series of 7 patients is also presented (4 tibiae, 3 femora). All patients had isolated bone lesions without metastases and were assessed through the hospital sarcoma board. Mean follow-up was 59 months (17–144). Mean age was 42 years. Final histologic diagnoses were 3 chondrosarcoma, 2 malignant fibrous histiocytoma, 1 adamantinoma and 1 malignant intraosseous nerve sheath tumour. Mean bone defect after resection was 13.1cm (10–17) and bone transport was the reconstruction method in all. There was one local recurrence of tumour six months post-resection, necessitating amputation. Mean frame index for remaining cases was 30.9 days/cm (15.7–41.6). Complications included pin infection, docking site non-union, premature corticotomy union, soft-tissue infection and minor varus deformity. Six cases remain tumour-free with united, well-aligned bones and good long-term function. We conclude DO provides an effective biologic reconstruction option in select cases of PMTLB

The purpose of this study is to provide a systematic review of the literature and assess outcome of our experience of Ilizarov Bone Transport in reconstruction for primary malignant tumours of bone (PMTB). A systematic review of the literature for reported cases of primary reconstruction of PMTB using distraction osteogenesis was performed. All cases of distraction osteogenesis for primary reconstruction of PMTB in our institution were reviewed. Outcome was determined from retrospective review of case notes and radiology. Patients were contacted to define final status. There are few cases of primary reconstruction of PMTB using Ilizarov method in the literature. Most reports relate to benign tumours or reconstruction of secondary deformities or non-union after tumour resection. At our institution we have treated 7 patients with bone defects resulting from excision of a PMTB. Mean age was 42.1 years (23–48). Tumours occurred in the tibia in 4 cases and the femur in 3 cases. Histologic diagnosis was chondrosarcoma in 3, malignant fibrous histiocytoma in 2, adamantinoma in 1 and malignant intraosseous nerve sheath tumour in 1. All patients were assessed through the hospital sarcoma board and shown to have isolated bone lesions without metastases. Mean bone defect after resection was 13.1 cm (10–17). Mean frame time was 13.6 months (5–23). Mean follow-up was 46 months (15–137). Complications included pin infection, docking site non-union, premature fusion of corticotomy, soft tissue infection and minor varus deformity. There was one local recurrence of tumour at five months after resection, resulting in a through hip disarticulation. The other cases remain tumour-free with united, well-aligned bones and acceptable long-term function. PMTB is rare and poses a major reconstructive dilemma. Distraction osteogenesis provides an effective method of biologic reconstruction in selected cases, and good outcomes can be achieved

Six patients underwent wide segmental resection and limb salvage surgery for primary or metastatic bone tumors involving the diaphysis of the femur, the tibia and the humerus using a modular intramedullary diaphyseal segmental defect fixation system. There were 4 men and 2 women with a mean age of 62 years (range, 40 to 77 years). Histological diagnosis included adamantinoma, dedifferentiated synovial sarcoma attached to the tibia, multiple myeloma, and metastatic renal cell carcinoma, myeloid carcinoma of the thyroid gland and metastatic adenocarcinoma of the stomach. The mean follow-up was 16 months (range, 11 to 24 months). At the latest examination, 5 patients were free of local or distant disease; one patient had deceased with distant disease, without evidence of local recurrence. Revision surgery was necessary in one patient because of mechanical loosening of the proximal fixation of the prosthesis. The mean increase of the Enneking rating from the pre to the postoperative status was 87.82%. The intramedullary diaphyseal segmental defect fixation system used herein is associated with a satisfactory functional and oncological outcome after wide resection of diaphyseal bone tumors

Purpose. To investigate the incidence of deep vein thrombosis (DVT) and pulmonary embolism (PE) with external fixator use and to help establish whether current guidelines are appropriate. Methods. Case notes of individuals undergoing external fixator application by the senior author (PC) from March 2005 to June 2011 were examined. In this period 207 individuals underwent 255 primary applications of Ilizarov, Taylor Spatial Frame (TSF) or monolateral fixator. Fixators applied were 173 tibial, 63 femoral and 19 to other bones. Records were obtained for 182 individuals (88%), representing 214 operations (84%). Results. Two cases of DVT were found (1%). In both cases mechanical and chemical prophylaxis had been used, as guided by risk assessment. One of these individuals also experienced a PE. This person was of notably high risk, surgery involving excision of tibial adamantinoma and a high body mass index (45). He had also recently travelled from overseas (a travel time of over 3 hours). Other than surgical time there was one additional risk factor in 39 cases, two additional risk factors in four and three additional risk factors in four. Conclusions. Little evidence exists about the incidence of DVT and PE with the use of external fixators. The National Institute of Health and Clinical Excellence (NICE) provide guidance for thromboprophylaxis in orthopaedic surgery with specific recommendations for hip and knee arthroplasty and hip fracture. For orthopaedic surgery other than lower limb arthroplasty NICE recommends thromboprophylaxis is guided by risk factors on a case by case basis. Our findings raise the question of whether extended course chemical thromboprophylaxis, as for lower limb arthroplasty, should be employed for high risk individuals undergoing application of external fixator

Purpose: We report three cases of extensive resection of the ulna without reconstruction. Material and methods: For the first two patients, resection was performed for ulnar tumour, on low-grade osteosarcoma and one adamantinoma. In the third patient with a voluminous giant-cell tumour, the distal part of the ulna was resected and used as a graft for arthrodesis after resection of the distal third of the homolateral radius. Resection involved the distal half, three-quarters, and one-third of the ulna in these three patients. Results: At follow-up of 4, 23 and 1 year respectively, wrist motion is normal in the two patients and elbow motion is normal in two out of three. None of the patients experienced wrist pain or ulnar stump pain. Grip force decreased in the two patients who underwent isolated ulnar resection. Discussion: Our observations corroborate reports in the literature leading to the conclusion that reconstruction of the ulna is not justified when one-quarter of the bone can be preserved. The ulna offers an exceptional graft material for reconstruction of the homolateral radius

Introduction. No published work exists regarding deep vein thrombosis (DVT) and pulmonary embolism (PE) incidence with the elective use of external fixators. The aim of this work was to establish the rate of DVT and PE in such cases to help inform whether thromboprophylaxis guided by risk factors is adequate or if a more aggressive approach is required. Patients and methods. Information from a prospectively maintained electronic database and case notes were examined for consecutive patients from March 2005 to June 2011. Occurrence of DVT and PE, detected by ultrasound or CT angiogram, were recorded. Risk factors for thromboembolism, age, weight, height, surgical indications, type of surgery and operative time were recorded. As recommended by the National Institute for Health and Clinical Excellence (NICE) thromboprophylaxis use is guided by risks of thromboembolism and bleeding. For adults and older adolescent patients contralateral leg compression stockings and an intraoperative calf pump were used. Mobilisation began the morning after surgery and the majority of cases permitted to bear weight fully. Results. Two hundred and seven (207) individuals underwent 255 primary applications of Ilizarov, Taylor Spatial Frame (TSF) or monolateral fixator, 173 tibial, 63 femoral and 19 to other bones. Case notes were obtained for 182 individuals (88%), representing 214 operations (84%). One DVT and one PE were recorded, an overall incidence of 2/214 (0.9%) (excluding those under 16 years old 2/143 (1.4%)). In both cases mechanical and chemical prophylaxis had been used as guided by risk assessment. The PE was sustained by a person of notably high risk, surgery involving excision of tibial adamantinoma and a high body mass index (45). He had also recently travelled from overseas (a travel time of over 3 hours). Conclusions. The rate of DVT/PE for elective application of external fixators is low with risk assessment guiding prophylaxis

Squamous cell carcinoma arising within bone is a rare lesion and is only seen essentially in the jaw and skull bones. Review of the medical literature showed that malignant change has been described in epidermoid cyst particularly in neurosurgical and orthodontic literature. However, no cases have been described in long bones as yet. Diagnosis of these tumours based on radiology and histology can be difficult and primary tumour elsewhere must be excluded. Here , a case of well differentiated squamous cell carcinoma arising from apparently a pre-existing intra-osseous epidermoid cyst in the distal tibia of a 45-year-old woman is reported. Initially treated with curettage and impact bone graft, then subsequently when the histopathology confirmed the above diagnosis, below knee amputation was performed. The differential diagnosis from other bone tumours with epithelial differentiation such as adamantinoma is discussed. This represents a rare primary neoplasm of bone of unknown histogenesis and also warns us to always try to get a histological diagnosis of what could look like clinically and radiologically a benign cyst

While classically bone tumors were classified according to the differentiation and cellular morphology at the light microscopical level, it has become clear that over the past decade the array of knowledge which became available on the cytogenetic and molecular genetic level should influence tumor classification. This lead to an integrated approach in drafting the 2002 WHO nomenclature for bone tumors in which morphology was combined with the evolving genetic information. With regard to bone tumorigenesis distinct patterns can be recognized with regard to underlying genetics:. balanced translocations such as in Ewing sarcoma, or aneurysmal bone cysts. numerical chromosomal abnormalities like in adamantinoma. complex karyotypes with as yet no identified starting point from a genetic point of view such as in osteosarcomas or central chondrosarcomas. single gene events such as in fibrous dysplasia or osteochondroma. These different pathways in oncogenesis open an array of possibilities for studying the drivers in oncogenesis. Especially those pathways essential in keeping the proliferative state as opposed to the ones governing differentiation might proof to be potential targets for tailored drug treatment. Here high throughput screens focusing on kinase activity appear especially of interest. Within the EuroBoNeT consortium (. www.eurobonet.eu. ) several working groups act transnationally together in unraveling these events. Important key elements of study are the molecular-genetic networks involved in skeletogenesis as well, which amongst others are studied within the consortium using in vitro systems as well as in vivo models using xenografted mouse models, mesenchymal stem cell models and models exploring zebrafish development