Neoadjuvant irradiation of extremity soft tissue sarcoma with ions (Extrem-ion): study protocol for a randomized phase II pilot trial.

BACKGROUND: The standard of care treatment for soft tissue sarcoma of the extremities is a wide resection in combination with pre- or postoperative radiotherapy with high local control rates, sparing patients the necessity of amputation without compromising on overall survival rates. The currently preferred timing of radiotherapy is under debate. Albeit having higher rates of acute wound complications, late side effects like fibrosis, joint stiffness or edema are less frequent in preoperative compared to postoperative radiotherapy. This can be explained in smaller treatment volumes and a lower dose in the preoperative setting. Particles allow better sparing of surrounding tissues at risk, and carbon ions additionally offer biologic advantages and are preferred in less radiosensitive tumors. Hypofractionation allows for a significantly shorter treatment duration. METHODS: Extrem-ion is a prospective, randomized, monocentric phase II trial. Patients with resectable or marginally resectable, histologically confirmed soft tissue sarcoma of the extremities will be randomized between neoadjuvant proton or neoadjuvant carbon ion radiotherapy in active scanning beam application technique (39 Gy [relative biological effectiveness, RBE] in 13 fractions [5-6 fractions per week] in each arm). The primary objective is the proportion of therapies without wound healing disorder the first 120 days after surgery or discontinuation of treatment for any reason related to the treatment. The secondary endpoints of the study consist of local control, local progression-free survival, disease-free survival, overall survival, and quality of life. DISCUSSION: The aim of this study is to confirm that hypofractionated, preoperative radiotherapy is safe and feasible. The potential for reduced toxicity by the utilization of particle therapy is the rational of this trial. A subsequent randomized phase III trial will compare the hypofractionated proton and carbon ion irradiation in regards to local control. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04946357 ; Retrospectively registered June 30, 2021.

[Specific intraoperative and secondary complications of biological reconstructions following extralesional tumour resections of malignant bone tumours]. / Operationstypische und sekundäre Komplikationen biologischer Rekonstruktionsverfahren nach extraläsionaler Tumorresektion bei malignen Knochentumoren.

BACKGROUND: The treatment of primary malignant bone tumours is interdisciplinary and individually adapted to the patient. Nowadays, limb salvage surgery is usually possible, and the subsequent reconstruction is carried out either by implantation of modular tumour megaprostheses or by biological reconstruction procedures. Special surgical and secondary complications have to be considered. OBJECTIVES: Indication and explanation of various biological reconstruction procedures and presentation of specific peri- and postoperative complications. MATERIALS AND METHODS: An adapted literature review and the contribution of our own therapy experiences and case studies for the presentation of biological reconstructions and their complication management was performed. RESULTS: In biological reconstructions, autografts, allografts or a combination of autografts and allografts are used. Stabilization is achieved with screw and plate osteosyntheses. The most common secondary complications are pseudarthrosis, interponate fracture, graft necrosis and secondary malpositions. CONCLUSION: In selected cases, particularly at the upper extremities and in dia- or metaphyseal tumour sites, biological reconstruction after extralesional tumor resection is the surgical therapy of choice. The rate of long-term revision interventions is significantly lower compared to modular tumour megaprostheses. Biological reconstructions and the treatment of specific complications have to be performed in specialized centres for musculoskeletal surgical oncology/tumor orthopedics.

Effects of multilevel surgery on a flexed knee gait in adults with cerebral palsy.

AIMS: A flexed knee gait is common in patients with bilateral spastic cerebral palsy and occurs with increased age. There is a risk for the recurrence of a flexed knee gait when treated in childhood, and the aim of this study was to investigate whether multilevel procedures might also be undertaken in adulthood. PATIENTS AND METHODS: At a mean of 22.9 months (standard deviation 12.9), after single event multi level surgery, 3D gait analysis was undertaken pre- and post-operatively for 37 adult patients with bilateral cerebral palsy and a fixed knee gait. RESULTS: There was a significant improvement of indices and clinical and kinematic parameters including extension of the hip and knee, reduction of knee flexion at initial contact, reduction of minimum and mean knee flexion in the stance phase of gait, improved range of movement of the knee and a reduction of mean flexion of the hip in the stance phase. Genu recurvatum occurred in two patients (n = 3 legs, 4%) and an increase of pelvic tilt (> 5°) was found in 12 patients (n = 23 legs, 31%). CONCLUSION: Adult patients with bilateral cerebral palsy and a flexed knee gait benefit from multilevel surgery including hamstring lengthening. The risk of the occurence of genu recurvatum and increased pelvic tilt is lower than has been previously reported in children. Cite this article: Bone Joint J 2017;99-B:1256-64.

[Diagnostics and treatment of benign spinal tumors]. / Diagnostik und Therapie benigner Tumoren der Wirbelsäule.

Benign tumors of the spine are rare and may lead to unspecific back pain. The classification of the lesion is typically achieved with a combination of imaging techniques (MRI and CT scans) and, in some cases, a histological sampling to allow differentiation from malignant processes. Both open and interventional (CT guided) biopsies are possible, depending on the localization of the tumor. Treatment strategies are diverse, require an interdisciplinary approach, and include operative and interventional procedures. The following article gives an overview of the most important benign tumors of the spine, the typical features in imaging, and treatment strategies.

Femoral derotation osteotomy in adults with cerebral palsy.

BACKGROUND: Internal rotation gait constitutes a complex gait disorder in bilateral spastic cerebral palsy (BSCP) including static torsional and dynamic components resulting in lever arm dysfunction. Although femoral derotation osteotomy (FDO) is a standard procedure to correct increased femoral anteversion in children, unpredictable outcome has been reported. The effect of FDO when it is done as part of single-event multilevel surgery (SEMLS) in adulthood has not been investigated. METHODS: In this study mid-term data of 63 adults with BSCP and internal rotation gait, undergoing SEMLS including FDO were analyzed pre- and 1.7 years postoperatively by clinical examination and 3D-instrumented gait analysis. All legs were categorized as the more or less involved side to consider asymmetry. The mean hip rotation in stance preoperatively and the intraoperative derotation was correlated with the difference pre- and postoperatively. RESULTS: The group as a whole experienced the following results postoperatively: improved mean hip rotation in stance (p=0.0001), mean foot progression angle (p=0.0001) and a significant improvement of the clinical parameter: passive internal and external hip rotation, midpoint and anteversion (p=0.0001) for both legs separately. With regard to the less and more involved side, clinical and kinematic parameters showed comparable significant changes (p=0.0001). The anteversion improved significantly in proximal compared to distal FDO (p=0.03). CONCLUSION: This study emphasizes an overall good correction of internal rotation gait in adults with bilateral involvement after FDO. However, the results are more predictable in adults compared to studies reporting outcome after FDO in children.

Factors associated with recurrence after femoral derotation osteotomy in cerebral palsy.

Femoral derotation osteotomy (FDO) as gold standard treatment for internal rotation gait in cerebral palsy (CP) leads to satisfying short-term results, whereas rates of recurrence up to 33% are reported in long-term outcome studies. The purpose of this study was therefore to identify factors contributing to recurrence of internal rotation gait in patients with CP who were treated with FDO in childhood. 70 patients (age: 10 (± 3.3) years at surgery) with bilateral CP and internal rotation gait were examined pre-, one year and at least five years (mean 8 ± 2 years) postoperatively after distal or proximal FDO, using standardized clinical examination and 3D gait-analysis. 27 patients had a good hip rotation one year postoperatively (between 5° external and 15° internal for both limbs) and were considered for the analysis of factors contributing to recurrence of internal rotation gait. Regarding all included patients both mean hip rotation and foot progression angle improved significantly (p < 0.001) from pre- to postoperative. A significant deterioration in hip rotation (more involved side) (p < 0.001) from one year postoperatively to the long-term follow-up can be observed. Younger age, reduced hip joint impulse, increased plantar flexion and internal foot progression angle postoperatively could be identified as factors for recurrence. FDO on average leads to a satisfactory correction of internal rotation gait. In order to improve the long-term outcome after FDO the time of multilevel surgery should be indicated as late as possible and the different factors leading to potential recurrence should be considered.