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G Ulrich Exner

Publications and source records attributed to G Ulrich Exner.

17 recordsLinked to original sources
PubMed2006

Skip metastases in osteosarcoma: experience of the Cooperative Osteosarcoma Study Group.

PURPOSE: The outlook for patients with osteosarcoma who present with synchronous regional bone metastases (skip metastases), either in the primary bone site or transarticular, is considered to be extremely poor. This study was conducted to further investigate the prognostic implication of skip metastases in osteosarcoma. PATIENTS AND METHODS: The authors retrospectively analyzed the collected data of 1,765 consecutive patients with newly diagnosed high-grade osteosarcoma of bone who were registered in the neoadjuvant Cooperative Osteosarcoma Study Group studies and identified 24 patients (1.4%) with unequivocally proven skip metastases. All 24 patients were treated by an aggressive surgical approach coupled with polychemotherapy. Demographic, diagnostic, tumor, and treatment-related variables and response and survival data were analyzed. RESULTS: Skip metastases were identified preoperatively in 11 of 24 patients by bone scan, eight of 22 patients by plain x-ray, 15 of 18 patients by magnetic resonance imaging, and five of 10 patients by computed tomography. A complete surgical remission (CSR) of all clinically detectable tumor sites was achieved in 22 of 24 patients during front-line therapy. With a median follow-up time of 4.4 years (8 years for survivors) from diagnosis, 12 patients were alive, all of whom were in continuous CSR. Survival did correlate with location of skip metastases and histologic response to neoadjuvant chemotherapy. CONCLUSION: Synchronous regional bone metastases are rare in osteosarcoma, and preoperative detection relies on appropriate diagnostic imaging. Aggressive multimodal therapy holds the promise to achieve prolonged survival, especially in patients in whom these metastases occur within the same bone as the primary lesion and whose tumors respond well to chemotherapy.

Adolescent↗
PubMed2006

HOXD10 M319K mutation in a family with isolated congenital vertical talus.

Congenital vertical talus (CVT) is a primary dislocation of the talonavicular joint that often occurs in neuromusculoskeletal syndromes, but may also be seen as an isolated abnormality. Six families with isolated CVT were ascertained. DNA was isolated from 21 affected individuals and 17 unaffected individuals from these families, as well as from five sporadic patients with CVT. Variable expressivity was noted in three families, manifesting as clubfoot in three individuals. Genome-wide linkage analysis generated a maximum two-point logarithm of odds score on chromosome 2q with D2S1353 (Zmax = 1.43 at theta(max) = 0.1), 17 Mb from the HOXD gene cluster. DNA from one affected individual of each family was subjected to mutational analysis of the HOXD10 gene. A single missense mutation was identified (M319K, 956T > A) in the homeodomain recognition helix of the HOXD10 gene that segregated with disease in one large British family. This mutation was recently described in a family of Italian descent with CVT and Charcot-Marie-Tooth deformity HOXD10 gene mutations were not identified in any of the other families or sporadic patients with CVT, suggesting that genetic heterogeneity underlies this disorder.

Chromosomes, Human, Pair 2↗
PubMed2006

Forces involved in lower limb lengthening: an in vivo biomechanical study.

Despite improvements in surgical techniques for limb-lengthening procedures, the complication rate remains high. Bone fixators must cope with the forces involved during treatment, providing sufficient strength to maintain integrity of the limb in the course of lengthening, while permitting some "micromotion" across the bone gap that could enhance healing during the final phase of bone consolidation. This study reports on the forces generated during limb lengthening in the distraction and consolidation phases. Forces were measured on 19 patients between 6 and 22 years of age with 10 femoral and 11 tibial lengthenings of 1 mm/day by means of a monotube external fixator, fitted diaphysially, and modified to measure tension and weight-bearing forces. Peak force measured during the lengthening period amounted to about 14 N/kg of body mass. Generally, distraction forces leveled off at between 8 and 10 N/kg of body mass. During the consolidation period, the average force carried by the fixator dropped from 55% initially to about 10% of the force transmitted to the ground, consistent with increased load carrying capacity of the bone as healing progressed. Studying the forces involved in limb lengthening is important to gain knowledge of the forces required to overcome the resistance offered by the tissues that bridge the osteotomy site, to understand the biology of distraction osteogenesis and histiogenesis across the regenerate over time, and to provide scientific guidelines for frame removal.

Adolescent↗
PubMed2006

Undisplaced femoral neck fractures in children have a high risk of secondary displacement.

Femoral neck fractures in children are rare and known to have a high complication rate (e.g. femoral head necrosis, persistent deformities, and pseudarthrosis). While open reduction and internal fixation is the treatment of choice for displaced fractures, non-operative treatment methods have been proposed if the fracture is undisplaced. Three consecutive patients aged 11, 14 and 16 years with undisplaced femoral neck fractures were seen at our institutions and primarily treated with the recommendation of non-weightbearing and minimal flexion until consolidation. All three cases showed secondary displacement within the first 6 weeks. A second minor indirect trauma caused displacement in one case; in the other two cases, no further trauma had occurred. All three fractures healed uneventfully following reduction and osteosynthesis. Undisplaced femoral neck fractures treated non-operatively evidently bear the risk of secondary displacement. The observations in these patients suggest that primary internal stabilization, even of undisplaced femoral neck fractures in children, should be considered.

Adolescent↗
PubMed2006

PET/CT of a brodie abscess.

Brodie abscess is a rare, localized type of subacute or chronic pyogenic osteomyelitis, usually of staphylococcal origin. Imaging with standard radiographs, bone scintigraphy, and MRI has been described in the literature. We present the case of a 28-year-old patient with pain in the right knee. Whole-body FDG-PET/CT scan showed a solitary FDG-active (SUV max 5.2) intracortical lesion in the meta-/epiphysis of the proximal tibia. CT demonstrated a sclerotic rim around the lesion. A Brodie abscess was considered a possible diagnosis. Multifocality could be excluded. CT-guided transosseous biopsy and curettage was performed and the diagnosis of a Brodie abscess was confirmed.

Abscess↗
PubMed2006

Avascular necrosis of the femoral head in sickle-cell disease: restoration of sphericity and congruency following triple pelvic osteotomy. A case report.

A 9-year-old boy, originally from Zaire, presented with homozygous sickle-cell disease and a unilateral avascular necrosis of the femoral head. He was treated with a triple pelvic osteotomy to improve containment and stimulate remodelling of the head following prior partial reduction in a spica cast. Four and a half years postoperatively the patient was pain free with normal hip function. Radiography revealed a well-centred hip with a mild coxa magna and a nearly spherical femoral head. In geographic regions with a small black population, sickle cell disease and related orthopaedic problems are rarely encountered, but one must be prepared for the occasional patient. Triple pelvic osteotomy for the treatment of femoral head necrosis associated with sickle cell disease has not yet been reported and has led in this case to a highly satisfying improvement of the hip.

Anemia, Sickle Cell↗
PubMed2005

Extraskeletal osteosarcoma has a favourable prognosis when treated like conventional osteosarcoma.

PURPOSE: The aims of this analysis were to investigate the clinical features of extraskeletal osteosarcoma (ESOS) and examine the outcome after multi-modal therapy. METHODS: The co-operative osteosarcoma study-group database was searched for patients with extraskeletal osteosarcoma. Eligible patients were included in a retrospective analysis of patient, tumour and treatment related variables and outcome. As for conventional osteosarcoma, scheduled treatment included surgery and multi-agent chemotherapy. RESULTS: Seventeen eligible patients were identified with a median age of 44 years (range, 3-65 years). The thigh was the commonest tumour site. Two patients had a history of previous malignancies and two had primary metastases. Median follow-up was 3.2 years (range: 0.6-7.4 years) and at last follow-up, 11 patients were alive in complete remission, 3 patients were alive with disease and 3 patients had died of their disease. Three-year overall actuarial and event-free survival rates were 77% and 56%, respectively. Patients with macroscopically complete surgical remission had an improved overall survival (P = 0.0004). CONCLUSIONS: The patients in this retrospective study had a surprisingly good survival rate. This may be due to the combination of multi-agent chemotherapy with surgery, and we recommend this approach in the treatment of ESOS.

Adolescent↗
PubMed2005

Osteosarcoma relapse after combined modality therapy: an analysis of unselected patients in the Cooperative Osteosarcoma Study Group (COSS).

PURPOSE: To evaluate the impact of patient, tumor, and treatment-related factors on outcome in unselected patients with recurrent osteosarcoma. PATIENTS AND METHODS: Five hundred seventy-six consecutive patients who had achieved a first complete surgical remission (CR) during combined-modality therapy on neoadjuvant Cooperative Osteosarcoma Study Group (COSS) protocols and then developed recurrent osteosarcoma were analyzed (median time from biopsy to relapse, 1.6 years; range, 0.1 to 14.3 years). There were 501 patients with metastases, 44 with local recurrences, and 31 with both. Metastases involved lungs (469 patients), bones (90 patients), and/or other sites (54 patients). RESULTS: After a median follow-up of 1.2 years for all patients and 4.2 years for survivors, actuarial overall survival (OS) rates at 2, 5, and 10 years were 0.38, 0.23, and 0.18, respectively. Five-year OS was 0.39 for 339 patients with and 0.00 for 229 patients without a second surgical CR (P < .0001). A long time to relapse, a solitary lesion, and, in the case of pulmonary metastases, unilateral disease and the absence of pleural disruption, were of positive prognostic value in uni- and multivariate analyses, as were a second surgical CR and the use of second-line chemotherapy. Radiotherapy was associated with moderately prolonged survival in patients without a second CR. The very limited prognostic differences associated with the use of second-line chemotherapy appeared to be more pronounced with polychemotherapy. CONCLUSION: Time to relapse and tumor burden correlate with postrelapse outcome in osteosarcoma. Complete surgery is an essential component of curative second-line therapy. Chemotherapy, particularly chemotherapy with more than one agent, may contribute to limited improvements in outcome.

Adolescent↗
PubMed2005

[Ankle arthrodesis for congenital absence of the fibula].

THE PROBLEM: Bilateral congenital absence of the fibula in a 10-year-old boy. A marked valgus malalignment at the left ankle and a foot with three rays caused pain during standing and walking. Ortheses did not help. Therefore, various treatment options were considered such as amputation of the foot, a supramalleolar correction osteotomy, and a tibiotalar arthrodesis. THE SOLUTION: Correction of malalignment and ankle arthrodesis stabilized with an external mini-fixator while sparing the distal tibial physis. SURGICAL TECHNIQUE: Two skin incisions: one on the medial side visualizing the flexor tendons and the neurovascular bundle while sparing the sural nerve and the small saphenous vein. Exposure of the medial malleolus after division of its ligamentous and capsular attachments. Localization of the ankle joint. The second incision on the lateral side. Z-lengthening of the sole peroneal tendon. Opening of the ankle joint at the lateral and anterior aspect. Resection of the articular surfaces of tibia and talus based on a preoperatively made drawing that showed an alignment of the hindfoot with the longitudinal axis of the tibia and the foot in 90 degrees in relation to the leg. Temporary insertion of a Kirschner wire from the sole of the foot into the tibia to maintain the obtained correction. Placement of a mini-fixator: one threaded Kirschner wire crosses the talocalcaneal synostosis, the second the distal tibial epiphysis, and the third one the proximal third of the tibia. Once the frame is mounted, compression of the resection surfaces and slight distraction between the proximal and middle Kirschner wires. RESULT: At the age of 16 years the boy is able to use a regular shoe with an orthotic insert; he is pain-free and can participate in all daily activities. The growth of the tibia has not been affected.

Ankle Joint↗
PubMed2003

Recurrent aggressive chondrosarcoma of the middle phalanx of the index finger: excision and reconstruction with an osteocartilaginous allograft.

INTRODUCTION: Chondrosarcomas are malignant tumours and need to be treated aggressively including ablative surgery. Bovée et al. and Mankin have recently drawn attention to a less aggressive behaviour of chondrosarcomas of the phalanges compared with those of other localizations including the metacarpals. MATERIALS AND METHODS: An 12 year follow-up of a patient with a chondrosarcoma of the middle phalanx of the index finger is presented. The lesion was curetted initially, and a repeat curettage was performed 4 years later. Finally, 8 years later the phalanx was excised and reconstructed with an osteocartilaginous allograft. Histologically, the lesion changed from a chondrosarcoma grade I to grade II. RESULT: The patient continues to be free of recurrence and metastases 4 years after the final resection. CONCLUSION: The potential for systemic disease of chondrosarcomas of the phalanges is probably much lower than in chondrosarcomas of other localizations, and therefore digit-sparing techniques may be considered rather than ablative procedures.

Bone Transplantation↗
PubMed2003

Osteosarcoma of the pelvis: experience of the Cooperative Osteosarcoma Study Group.

PURPOSE: To define patients and tumor characteristics as well as therapy results, patients with pelvic osteosarcoma who were registered in the Cooperative Osteosarcoma Study Group (COSS) were analyzed. PATIENTS AND METHODS: Sixty-seven patients with a high-grade pelvic osteosarcoma were eligible for this analysis. Fifteen patients had primary metastases. All patients received chemotherapy according to COSS protocols. Thirty-eight patients underwent limb-sparing surgery, 12 patients underwent hemipelvectomy, and 17 patients did not undergo definitive surgery. Eleven patients received irradiation to the primary tumor site: four postoperatively and seven as the only form of local therapy. RESULTS: Local failure occurred in 47 of all 67 patients (70%) and in 31 of 50 patients (62%) who underwent definitive surgery. Five-year overall survival (OS) and progression-free survival rates were 27% and 19%, respectively. Large tumor size (P =.0137), primary metastases (P =.0001), and no or intralesional surgery (P <.0001) were poor prognostic factors. In 30 patients with no or intralesional surgery, 11 patients with radiotherapy had better OS than 19 patients without radiotherapy (P =.0033). Among the variables, primary metastasis, large tumor, no or intralesional surgery, no radiotherapy, existence of primary metastasis (relative risk [RR] = 3.456; P =.0009), surgical margin (intralesional or no surgical excision; RR = 5.619; P <.0001), and no radiotherapy (RR = 4.196; P =.0059) were independent poor prognostic factors. CONCLUSION: An operative approach with wide or marginal margins improves local control and OS. If the surgical margin is intralesional or excision is impossible, additional radiotherapy has a positive influence on prognosis.

Adolescent↗
PubMed2003

Bending osteotomy through the distal tibial physis in fibular hemimelia for stable reduction of the hindfoot.

Fibular hemimelia is associated with a deformity of the distal tibial epiphysis resulting in a convexity with lateral and posterior slope of the distal joint surface. The deformity results into an equinovalgus position of the foot and ankle and frequently consecutive dislocation of the foot. A new procedure is presented, in with a metaphyseal ostotomy is performed towards the physis in order to bend the postero-lateral third of the distal tibial epiphysis forming a concave distal tibial joint surface. This procedure was done in four feet in three patients at ages between 7 and 20 months combined with soft tissue releases and rebalancing the tendons. At a follow-up between 6 and 42 months the position of the feet is well retained.

Ectromelia↗
PubMed2003

Supracondylar medial open wedge osteotomy with external fixation for cubitus varus deformity.

BACKGROUND: Many surgical procedures are used for the correction of cubitus varus deformity in children. Even if the primary indication is cosmetic, but many poor results have been described. The technique of a supracondylar medial opening wedge osteotomy with external fixation is presented and preliminary results in four cases are reported. TECHNIQUE: An antero-medial approach is chosen with exposition and anterior transposition of the ulnar nerve. Under image intensifier control, insertion of four Schanz screws is performed from medial to lateral. In between, an incomplete medial osteotomy is performed obliquely (in the antero-posterior as well as in the medio-lateral plane), leaving a small part of the radial humeral cortex intact. The osteotomy is opened until varus and, if present, hyperextension deformation are corrected. Then, the fixator system is applied. RESULTS: All osteotomies healed primarily. Mean valgus correction of 21.75 degrees was achieved; in only one patient additional flexion modification of 17 degrees was necessary. At a follow-up of at least 2 years clinically three out of four presented symmetric elbow position, one slight residual varus deformity was noted in spite of 20 degrees of valgization due to important valgus position of the contralateral side. No lateral bulging of the corrected elbow was observed. CONCLUSION: The described technique is an alternative to other procedures, with special regard to the cosmetic outcome as well as to the control of correction for valgus and flexion.

Child↗
PubMed2002

Prognostic factors in high-grade osteosarcoma of the extremities or trunk: an analysis of 1,702 patients treated on neoadjuvant cooperative osteosarcoma study group protocols.

PURPOSE: To define prognostic factors for response and long-term outcome for a wide spectrum of osteosarcomas, extending well beyond those of the typical young patient with seemingly localized extremity disease. PATIENTS AND METHODS: A total of 1,702 consecutive newly diagnosed patients with high-grade osteosarcoma of the trunk or limbs registered into the neoadjuvant studies of the Cooperative Osteosarcoma Study Group before July 1998 were entered into an analysis of demographic, tumor-related, and treatment-related variables, response, and survival. The intended therapeutic strategy included preoperative and postoperative chemotherapy with multiple agents as well as surgery of all operable lesions. RESULTS: Axial tumor site, male sex, and a long history of symptoms were associated with poor response to chemotherapy in univariate and multivariate analysis. Actuarial 10-year overall and event-free survival rates were 59.8% and 48.9%. Among the variables assessable at diagnosis, patient age (actuarial 10-year survival > or = 40, 41.6%; < 40, 60.2%; P =.012), tumor site (axial, 29.2%; limb, 61.7%; P <.0001), and primary metastases (yes, 26.7%; no, 64.4%; P <.0001), and for extremity osteosarcomas, also size (> or = one third, 52.5%; < one third, 66.7%; P <.0001) and location within the limb (proximal, 49.3%; other, 63.9%; P <.0001), had significant influence on outcome. Two additional important prognostic factors were treatment related: response to chemotherapy (poor, 47.2%; good, 73.4%; P <.0001) and the extent of surgery (incomplete, 14.6%; macroscopically complete, 64.8%; P <.0001). All factors except age maintained their significance in multivariate testing, with surgical remission and histologic response emerging as the key prognostic factors. CONCLUSION: Tumor site and size, primary metastases, response to chemotherapy, and surgical remission are of independent prognostic value in osteosarcoma.

Adolescent↗
PubMedDate not supplied

Arthropathy of the knee joint caused by synovial hemangioma.

Degenerative changes resembling hemophilic arthropathy may be a complication of synovial hemangioma in the knee. It is thought that arthropathy is caused by repeated bleeding episodes similar to the joint disease in hemophilia. Four children aged 4 to 9 years at surgery were treated by anterior open synovectomy for intra-articular synovial hemangiomas. At open surgery the cartilage of all patients showed changes on the surface with yellow hematin staining in all cases, without ulceration in three patients but one, who showed severe degenerative changes at age 9 years. At 15 months follow-up the patient with severe degenerative changes had severely impaired flexion and mild extension deficit. The three others were asymptomatic at 1 to 6 years follow-up. The magnetic resonance images were typical and can be considered pathognomonic; however, the referral diagnosis included the correct diagnosis in none of them. Treatment should be initiated as early as possible to reduce the risk of damage to the cartilage. Treatment by complete open synovectomy in these four patients was performed without significant bleeding problems, and no recurrence was seen.

Cartilage, Articular↗