Limb salvage in traumatic hemipelvectomy: case series with surgical management and review of the literature.

BACKGROUND: Traumatic hemipelvectomies are rare and serious injuries. The surgical management was described in several case studies, with primary amputation often performed to save the patient's life. METHODS: We report of two survivors with complete traumatic hemipelvectomy resulting in ischemia and paralyzed lower extremity. Due to modern emergency medicine and reconstructive surgery, limb salvage could be attained. Long-term outcome with quality of life was assessed one year after the initial accident. RESULTS AND CONCLUSIONS: The patients were able to mobilize themselves and live an independent life. The extremities remained without function and sensation. Urinary continence and sexual function were present and the colostomy could be relocated in both patients. Both patients support limb salvage, even having difficulties and follow-up treatments. Concomitant cases are required to consolidate the findings. LEVEL OF EVIDENCE: IV.

eCross-cultural adaptation of the spine oncology-specific SOSGOQ2.0 questionnaire to German language and the assessment of its validity and reliability in the clinical setting.

BACKGROUND: The recently developed Spine Oncology Study Group Outcomes Questionnaire (SOSGOQ2.0) was proven a valid and reliable instrument measuring health-related quality of life (HRQOL) for patients with spinal malignancies. A German version was not available. OBJECTIVE: A cross-cultural adaptation of the SOSGOQ2.0 to the German language and its multicenter evaluation. METHODS: In a multistep process, a cross-cultural adaptation of the SOSGOQ2.0 was conducted. Subsequently, a multicenter, prospective observational cohort study was initiated to assess the reliability and validity of the German adaptation. To assess external construct validity of the cross-cultural adapted questionnaire, a comparison to the established questionnaire QLQ-C30 from the European Organisation for Research and Treatment of Cancer was conducted. Mean-difference plots were used to measure the agreement between the questionnaires in total score and by domain (deviation from mean up to 10% allowed). Further reliability and validity tests were carried out. Change to baseline was analysed 3-16 weeks later after different interventions occurred. Clinically relevant thresholds in comparison to the EORTC QLQ-C30 questionnaire were evaluated by ROC curve analysis. RESULTS: We could enroll 113 patients from four different university hospitals (58 females, 55 males). Mean age was 64.11 years (sd 11.9). 80 patients had an ECOG performance status of 2 or higher at baseline. External construct validity in comparison to the EORTC QLQ-C30 questionnaire in total score and by domain was confirmed (range of deviation 4.4 to 9.0%). Good responsiveness for the domains Physical Functioning (P < .001) and Pain (P < .001) could be shown. The group mean values also displayed a difference in the domains of Social Functioning (P = .331) and Mental Health (P = .130), but not significant. The minimum clinically relevant threshold values for the questionnaire ranged from 4.0 to 7.5 points. CONCLUSIONS: According to our results, the cross-cultural adapted questionnaire is a reliable and valid tool to measure HRQOL in German speaking patients with spinal malignancies. Especially the domains Physical Functioning and Pain showed overall good psychometric characteristics. In this way, a generic questionnaire, such as the EORTC QLQ-C30, can be usefully supplemented by spine-specific questions to increase the overall accuracy measuring HRQOL in patients with spinal malignancies.

[Biopsy of musculoskeletal tumors : Complications and avoidable errors]. / Biopsie muskuloskeletaler Tumoren : Komplikationen und vermeidbare Fehler.

Biopsy followed by histopathological assessment is the key procedure to establish the correct diagnosis of unclear bone or soft tissue tumors. There are several possibilities to obtain a biopsy specimen. The indication for biopsy should be established in a specialized center, as should the type of biopsy (fine needle, incisional, excisional, percutaneous CT-guided/navigated biopsy), which must be performed according to established guidelines. The tumor biopsy must be representative and adequate in terms of quantity, to enable a conclusive histopathological diagnosis and planning of appropriate treatment. For the correct biopsy tract, the surgical approach for definitive resection must be considered; thus, biopsy should be conducted in the center where the subsequent resection will be performed. Of note, patients whose biopsy is performed at a specialized musculoskeletal tumor center benefit in terms of improved local tumor control.

[Complication profile and revision concepts for megaprosthetic reconstruction following tumour resection at the hip]. / Komplikationsprofil und Revisionsstrategien nach Tumorspezialendoprothetik am Hüftgelenk.

BACKGROUND: Tumourous destruction of the periacetabular region and the proximal femur is a typical consequence of either primary malignant bone tumour manifestation or skeletal metastatic diseases. Pathological fractures of the proximal femur and periacetabular regions due to primary manifestation or metastatic disorders are frequent. OBJECTIVES: Presentation of the most common complications of tumour endoprostheses at the hip and a description of management strategies, including therapeutic recommendations and concepts for complication avoidance. MATERIALS AND METHODS: The current knowledge and our own experience of complication management with the use of megaprostheses around the hip are presented. RESULTS: Compared to elective/primary total hip arthroplasty, megaprosthetic reconstructions following tumour resections have an increased rate of postoperative deep infections, dislocations, incidence of pathological and periprosthetic fractures and of deep vein thrombosis. The postoperative mortality and local tumour recurrence along with deep infections represent the most serious complications. CONCLUSIONS: In comparison to primary arthroplasty, the risk of failure and complications following tumour-endoprosthetic replacement is increased. Precise surgical planning and careful selection and preoperative preparation of suitable patients should be performed in close interdisciplinary cooperation with final decision-making on an interdisciplinary tumour board. Wide resection and advanced reconstruction, as well as complicated palliative stabilization due to malignant bone tumour growth around the hip joint should be performed in musculoskeletal tumour centres with profound expertise in osteosynthetic and endoprosthetic reconstruction and consecutive complication management of the pelvis and the proximal femur.

[Risk factors and management strategies for early and late infections following reconstruction with special tumour endoprostheses]. / Risikofaktoren und Managementstrategien des Früh- und Spätinfektes nach Rekonstruktion mit Tumorspezialendoprothesen.

BACKGROUND: Periprosthetic joint infection (PJI) of megaprostheses occur in about 10% of all cases. The criteria for PJI are defined by the "Musculoskleletal Infection Society" (MSIS) and apply to both primary arthroplasty and megaprostheses. MANAGEMENT: The management strategies of PJI in megaprostheses are dependent on the duration of infection and the maturity of the bacterial biofilm. Implant retention with an exchange of the mobile components is only possible in the presence of an immature biofilm. In the presence of a mature biofilm, a one- or two-stage exchange must be performed. A complete exchange of all endoprosthetic components should be performed, if possible, since a partial retention of isolated components results in inferior treatment success rates. RESULTS: The highest success rates are achievable with two-stage exchanges. Multiple risk factors such as skin necrosis, postoperative haematoma, prolonged wound secretion and operative times ≥ 2.5 h are risk factors for the development of PJI in megaprostheses. Knowledge regarding these risk factors allows for an identification of high-risk patients and early management of PJI.

[Intraoperative and late complications after spinal tumour resection and dorsoventral reconstruction]. / Intraoperative und späte Komplikationen nach spinaler Tumorresektion und dorsoventraler Rekonstruktion.

BACKGROUND: Spinal tumors are a continuously growing pathology group among the spinal diseases. The often-difficult circumstances increase vulnerability to a wide range of intervention-related complications, which can occur at different times in the course of the disease and must be included in the consideration of the indication. OBJECTIVES: The aim of the work is to present the wide spectrum of complications in the surgical treatment of spinal tumors, as well as their treatment and prophylaxis through optimal therapy management. MATERIALS AND METHODS: The article summarizes the current literature. RESULTS: The literature describes complication rates of 10-67% after metastatic surgery of the spinal column. The most common complications are infections and internal, especially pulmonary, complications. Other relevant complications include surgical positioning/surgical access/instrumentation/mechanical failure, and anesthesiological, neurological, vascular and oncological complications. The socio-economic costs for patients with complications compared to those for patients without complications are twice as high. A special risk situation exists with radical spinal tumor resections. Negative predictors are previous operations, previous irradiation and local recurrences. CONCLUSIONS: An early, interdisciplinary concept can reduce complications significantly. Due to the planning intensity, surgical expertise and comprehensive structural requirements, treatment in an interdisciplinary tumour centre is necessary.

Current surgical strategies for treating spinal tumors: Results of a questionnaire survey among members of the German Spine Society (DWG).

PURPOSE: Questionnaire survey among the members of the German Spine Society (Deutsche Wirbelsäulen-Gesellschaft, DWG) to objectify oncological infrastructure and current standard of care in spinal tumor treatment in Germany. METHODS: All DWG-members were contacted via the society's e-mail and asked to respond in anonymized form to a related questionnaire. Questions were asked regarding surgical specialty, type of institution involved, numbers of spinal procedures, as well as questions on treatment for primary tumors, whether the respondent belonged to a tumor center, decision-making procedures for surgery, and the type of procedure. RESULTS: 84 centers providing surgical treatment for spinal tumors in their departments were identified. 52.6% were carrying out more than 500 spinal procedures per year. There was a significant association (P ≤ 0.05) between the numbers of spinal surgeries, the number of treated tumor patients per year, the organisation in a tumor center and the treatment of primary tumors. 76% are part of a local tumor center for interdisciplinary decision making (i.e.surgical treatment and adjuvant therapy). 74% of the institutions stated that conventional postoperative radiotherapy is standardly administered in the case of secondary lesions, with 24% of them referring patients to external services for radiotherapy. CONCLUSION: In spite of often large numbers of spinal operations, the centers perform relatively small numbers of tumor operations, particularly for primary tumors. A nearly three-quarter majority of the departments are integrated into interdisciplinary tumor care. However, there is a marked number that do not belong to an interdisciplinary organisation. Further advances in multidisciplinarity and oncology training are a continuous issue to increase treatment quality in spinal tumor patients.

[Management of complications following tumor endoprosthetic replacement]. / Komplikationsmanagement nach Tumorendoprothesen.

BACKGROUND: Tumor endoprostheses are available as modular systems with which bone defects can be partially reconstructed, usually close to the joints, or as a total replacement of long tubular bones. As a result of continuously improved survival times, they are used with bone tumors, skeletal metastases and, increasingly, in revision arthroplasty. OBJECTIVES: Presentation of the most common complications of tumor endoprostheses and a description of their management, including treatment recommendations. MATERIALS AND METHODS: The current knowledge and our own experience of complication management with the use of megaprostheses are presented. RESULTS: The number of tumor endoprostheses procedures is limited, so that a limited number of studies and classifications are available. Periprosthetic infections involving the soft tissues represent the most serious failure after perioperative dying and local recurrence of the tumor. Two-stage revision remains the gold standard in periprosthetic infection, even if one-stage revision is justifiable in selective indications. Periprosthetic infection and local recurrence is associated with the risk of secondary amputations. Mechanical failure can be treated more easily. Specific socket systems for proximal femoral replacement and attachment tubing allow for adequate soft tissue reconstruction, restoration of joint function, and minimize the risk of dislocation. CONCLUSIONS: In comparison to primary arthroplasty, the risk of failure following tumor endoprosthetic replacement is increased but is basically controllable by revision surgery.

Cardiac disease and advanced age increase the mortality risk following surgery for periprosthetic femoral fractures.

AIMS: Periprosthetic fracture is a significant complication of total hip and knee arthroplasty. This study aimed to describe the survival of patients sustaining periprosthetic femoral fractures and compare this with that of the general population, as well as to identify the factors that influence survival. PATIENTS AND METHODS: A total of 151 patients (women: men 116:35, mean age 74.6 years, standard deviation 11.5) that sustained a periprosthetic fracture between January 2005 and October 2012 were retrospectively analysed. Epidemiological data, comorbidities, type of surgical management, type of implant, and mortality data were studied. RESULTS: The mean survival time was 77 months (95% confidence interval 71 to 84; numbers at risk: 73) and was lower than that of the general population. The risk analyses showed that previous cardiac disease, particularly ischaemic heart disease, cardiac arrhythmias, and heart failure, age over 75 years and American Society of Anesthesiologists (ASA) scores above 3 were associated with a significantly higher mortality. CONCLUSIONS: Periprosthetic fractures carry a high risk of post-operative mortality. Our data demonstrate that advanced age (> 75 years) and previous cardiac disease are associated with a significantly higher risk of mortality. The ASA score is an appropriate instrument for risk stratification. Pre-operative cardiac status should be optimised before surgery. Cite this article: Bone Joint J 2017;99-B:921-6.

[Benign tumours and tumour-like lesions of the bone : General treatment principles]. / Benigne Tumoren und tumorähnliche Läsionen des Knochens : Allgemeine Behandlungsprinzipien.

BACKGROUND: Benign bone lesions are much more common than malignant lesions. Some benign bone tumors have a characteristic and typical radiographic appearance, while others are more challenging. Therapy of benign bone tumors differs greatly. While the majority of benign bone tumors do not require surgical therapy, other specific lesions, e. g. aneurysmal bone cysts or giant cell tumors (GCT) of the bone require surgery due to their locally aggressive behavior. DIAGNOSTICS: The major challenge for the radiologist and/or pathologist is the differentiation between a benign and low-grade malignant lesion (e. g. enchondroma versus low-grade chondrosarcoma) for which all available clinical and radiographic information is mandatory. Therefore, surgical therapy is rather more often performed than necessary due to uncertainty in many cases. THERAPY: Novel systemic therapies are available for fibrous dysplasia and GCT of the bone: Fibrous dysplasia can be treated with bisphosphonates, and GCT responds to denosumab. In fact, denosumab has been approved for the treatment of irresectable GCT. Osteoid osteoma is fairly easy to recognize and also to treat given the characteristic clinical presentation and rapid and effective response to local therapy (possible as percutaneous thermo-/laser ablation). In summary, several therapeutic options exist for benign bone tumors, and the choice depends upon the tendency/risk of local recurrence, the rate of surgical complications, options for defect reconstruction, postoperative functional deficits, and specific patient characteristics.

[Corrective osteotomies for posttraumatic elbow deformities]. / Korrekturosteotomien bei posttraumatischen Fehlstellungen des Ellenbogengelenks.

OBJECTIVES: Correcion of elbow joint deformities that usually develop secondary to direct or indirect trauma of the arm or elbow with subsequent inadequate healing and consecutive axial/rotational malalignment and may be associated with cosmetic or functional deficits of the arm. INDICATIONS: Relevant malalignment of the arm axis with corresponding cosmetic or functional deficits for the patient. CONTRAINDICATIONS: Pre-existing degenerative and chronic inflammatory changes. SURGICAL TECHNIQUE: Generally, two-dimensional supracondylar open or closed wedge osteotomies are used. In the presence of a three-dimensional deformity (with rotational component), an additional derotational correction is necessary. Extra-articular deformities following extension fractures should be treated preferably with an open wedge osteotomy, extra-articular deformities of flexion fractures with a closed wedge osteotomy. Valgus/varus deformities may also require a closed/open wedge osteotomy primarily through a dorsal or alternatively radial approach. POSTOPERATIVE MANAGEMENT: The arm should be immobilized with a brachial cast splint for 2-3 weeks, with passive exercises of the elbow starting on postoperative day 7. RESULTS: In general, the results for a three-dimensional osteotomy of the distal humerus are expected to be good to very good. Only in rare cases (2.5%) is a mostly transient irritation of the ulnar nerve observed.

Evaluation of radiographic fracture position 1 year after variable angle locking volar distal radius plating: a prospective multicentre case series.

Treatment with a variable angle locking plate can, in theory, maintain near anatomic reduction of intra-articular distal radius fractures, but it is unknown to what extent reduction is maintained as measured by computed tomography. We assessed changes in radiographic fracture position 1 year post-operatively. We included 73 patients of whom 66 patients (90%) had radiographs available for review at 1 year post-operatively. We found a small (less than 2 mm or 2°) but statistically significant change in several measures. Accounting for inter-observer variability, this is probably within measurement error. We found no difference in change in fracture position or range of motion, grip strength or patient-reported outcome between the use of one or two distal rows of screws. Our results show that minimal changes in reduction can be expected after volar plate fixation in most patients. We recommend using only one screw row routinely, limiting costs, surgical time and the risk of misplacement of screws. LEVEL OF EVIDENCE: IV.

[Consequences of the Foundation of a University Centre for Orthopaedics and Accident Surgery]. / Effekte der Gründung eines UniversitätsCentrums für Orthopädie und Unfallchirurgie.

Background: Since the combination of orthopaedic and traumatology surgery as a single speciality, an extremely wide variety of orthopaedic and trauma surgery centres have been founded in Germany. The present investigation analysed the degree to which additional value has been generated by merging two previously independent university departments - one for orthopaedics, the other for trauma surgery - into a single orthopaedics and trauma surgery centre. Material and Methods: The centre, merged in 1 June 2013, is led by two equal co-chairs (a full professor for orthopaedics and a full professor for trauma surgery). It consists of an acute division and five other divisions for specific parts of the body. The pre-existing certifications (level 1 trauma- and joint arthroplasty centre) were maintained in the new merged entity. Data from patient and employee questionnaires, as well as key economic indicators, were compared before and after the merger. Results: 11 % of the patients rated the medical treatment as mediocre or bad before the merger. After the merger, 5.7 % of the patients were moderately satisfied or unsatisfied; 92 % would recommend the merged centre to others and would return for further treatment. The evaluation of patient complaints before and after the merger showed no change. The evaluation of the employee questionnaires showed heterogeneous results. Overall, positive evaluations predominated, but in areas where there had been major changes, negative aspects were occasionally reported. The merger did not bring about any essential change in the number of in-patients (2012: 6693; 2014: 6649) or in the severity of the medical cases (CMI in 2012: 1.41; in 2014: 1.45). But in 2015, there was an increase in the number of in-patients (6837) and in the CMI (1.54). In the out-patient clinic, the merger led to a reduction in the material costs per patient (2012: 3.53 €/patient; 2014: 3.07 €/patient) and in the staff costs. The material costs for the entire centre were also reduced by 14 %. Conclusion: By merging the university orthopaedic and trauma surgery centres, transdisciplinary and transdepartmental improvements in patient care were achieved for musculoskeletal illnesses and injuries, and a sustainable structure was established for the advanced training for the joint specialist title of orthopaedics and trauma surgery. The merger also led to additional economic synergies, with a mid-term potential for increases in the number of patients and in CMI. To improve or at least maintain the level of employee satisfaction, staff must be actively included in the process.

[Osteosynthesis and cup revision in periprosthetic acetabulum fractures using a Kocher-Langenbeck approach]. / Osteosynthese und Pfannenwechsel bei periprothetischer Azetabulumfraktur über einen Kocher-Langenbeck-Zugang.

OBJECTIVE: Reconstruction/stable fixation of the acetabular columns to create an adequate periacetabular requirement for the implantation of a revision cup. INDICATIONS: Displaced/nondisplaced fractures with involvement of the posterior column. Resulting instability of the cup in an adequate bone stock situation. CONTRAINDICATIONS: Periprosthetic acetabulum fractures with inadequate bone stock. Extended periacetabular defects with loss of anchorage options. Isolated periprosthetic fractures of the anterior column. Septic loosening. SURGICAL TECHNIQUE: Dorsal approach. Dislocation of hip. Mechanical testing of inlaying acetabular cup. With unstable cup situation explantation of the cup, fracture fixation of acetabulum with dorsal double plate osteosynthesis along the posterior column. Cup revision. Hip joint reposition. POSTOPERATIVE MANAGEMENT: Early mobilization; partial weight bearing for 12 weeks. Thrombosis prophylaxis. Clinical and radiological follow-ups. RESULTS: Periprosthetic acetabular fracture in 17 patients with 9 fractures after primary total hip replacement (THR), 8 after revision THR. Fractures: 12 due to trauma, 5 spontaneously; 7 anterior column fractures, 5 transverse fractures, 4 posterior column fractures, 1 two column fracture after hemiendoprosthesis. 5 type 1 fractures and 12 type 2 fractures. Operatively treated cases (10/17) received 3 reinforcement ring, 2 pedestal cup, 1 standard revision cup, cup-1 cage construct, 1 ventral plate osteosynthesis, 1 dorsal plate osteosynthesis, and 1 dorsal plate osteosynthesis plus cup revision (10-month Harris Hip Score 78 points). Radiological follow-up for 10 patients: consolidation of fractures without dislocation and a fixed acetabular cup. No revision surgeries during follow-up; 2 hip dislocations, 1 transient sciatic nerve palsy.

[Complication management of infected osteosynthesis: Therapy algorithm for peri-implant infections]. / Komplikationsmanagement bei infizierter Osteosynthese : Therapiealgorithmus bei periimplantären Infektionen.

BACKGROUND: Peri-implant infections (PII) are one of the most frequent postoperative complications and require an individualized combined surgical and antibiotic management. In this review article we provide up to date scientific knowledge regarding the pathogenesis, classification, diagnosis and therapy of PII. The aim of this article is to explain the rational background and evidence of individual treatment options in order to elaborate concrete management recommendations. MATERIAL AND METHODS: The relevant scientific publications were critically reviewed for diagnostics, therapy and prevention of PII. Based on these data we present a combined surgical and antibiotic treatment algorithm for PII. RESULTS: With a consistent interdisciplinary action high healing rates with eradication of PII can be achieved. In acute PII (< 6 weeks) the implant can normally be retained but this is dependent on the soft tissue conditions, while in chronic PII (> 6 weeks) the implant generally has to be removed in a one or two step exchange, depending on the soft tissue, bone defects and pathogen. CONCLUSION: Scientific knowledge and clinical data have led to new treatment algorithms for PII with improved outcome, decreased morbidity and shortened hospitalization. Systemic individualized antimicrobial therapy, radical septic and plastic surgery are the cornerstones for successful treatment of acute and chronic PII. The local use of antibiotics and application of bone substitute materials are other techniques for treatment but the exact importance must still be determined.

Quality of life and functional outcome of periprosthetic fractures around the knee following knee arthroplasty.

PURPOSE OF THE STUDY The present study aimed to analyse both, the functional outcome and quality of life after surgical treatment of periprosthetic fractures following TKA. MATERIAL AND METHODS A retrospective review of all periprosthetic fractures following knee arthroplasty which have been surgically treated at our institution between January 2005 and January 2012 was conducted. Beside epidemiologic data, type of surgery and postoperative complications were recorded. The functional outcome was assessed using range of motion, Knee Society Score and VAS to evaluate pain. Quality of life was evaluated using SF-36 and WOMAC. Furthermore patients mobility and comorbidities were analysed. RESULTS 25 (mean age 76 ± 8 years; m:w 5:20) patients were included. The overall complication rate was 24%. Mean KSS knee score was 73 ± 19 and a function score was 41 ± 36. Range of motion revealed 95° ± 24° (active) and 98° ± 16° (passive). The total SF-36 scored a mean of 41 ± 6 and 29 ± 19 in average considering the WOMAC index (pain: 19 ± 20; stiffness: 23 ± 27; daily: 47 ± 29). 20% were able to mobilise without help as opposed to 80% that were in need for assistance. Our analysis revealed no influence of the final outcome as a function of fracture type or type of treatment. Multiple regression analysis could not reveal significant influence of the comorbidities. CONCLUSION Periprosthetic fractures following knee arthroplasty are accompanied by a significant decrease of the knee function and quality of life as well as high complication rates. Since patient's quality of life apparently depends on the functional outcome, future efforts should aim to improve these parameters. Key words: periprosthetic fracture, total knee arthroplasty, quality of life, functional outcome, locking plate.

Skeletal metastatic disease of the femur: results by management with intramedullary nailing.

PURPOSE OF THE STUDY This study aimed to analyse the outcome following intramedullary nailing for metastases of the femur in a large cohort with special regard to mechanical, implant associated complications and patient survival. Furthermore, we aimed to identify factors influencing the overall survival. MATERIAL AND METHODS All patients (n = 74) that underwent intramedullary nailing for metastatic disease of the femur between 2004 and 2008 and were retrospectively reviewed. Data were recorded from the patients' medical record and the outpatients' clinics files. Details about the tumour biology, the surgery performed as well as the postoperative care were documented. Survival data were extracted from patient records or obtained via communication with outpatient oncologists or the community registration office. RESULTS 74 (28 (37.8%) male, 46 (62.2%) female; p = 0.048) patients with a mean age of 64.4 ± 11.7 years were included. Breast (25, 33.8%), lung (18, 24.3%), bone marrow (7, 9.5%) and kidney (6, 8.1%) were the primary tumours in more than 75% of all patients. The mean overall survival was 17.5 (95% CI: 9.6 - 25.5) months. Patients with osseous metastases had a significant longer survival than patients with visceral and/or cerebral metastases (p = 0.025 and p = 0.032). CONCLUSION Intramedullary nailing represents a valuable fixation method for pathologic fractures or impending fractures of the femur in patients with an advanced stage of metastatic disease. It provides adequate stability to outlast the patient s remaining life-span. However, the balance must be found between therapeutic resignation and surgical overtreatment since operative treatment may be accompanied with serious complications. Key words: bone metastases, intramedullary nailing, metastatic disease, cement augmentation, osteolytic defect.

[Benign cystic bone lesions]. / Benigne zystische Knochenläsionen.

BACKGROUND: Bone cysts are benign tumor-like lesions which often present as a fluid-containing cavity in the bone. They can occur in the skeletal bone as solitary or sometimes multiple bone lesions. OBJECTIVES: This review discusses the diagnostics, radiological appearance and therapeutic strategies of the most important benign cystic bone lesions, such as simple bone cysts, aneurysmal bone cysts, intraosseous ganglia, epidermoid cysts and subchondral cysts. The differential diagnoses with respect to cystoid formations and tumors with cystic components are discussed. METHOD: A selective literature search was performed taking own experiences into consideration. RESULTS: These tumor-like lesions can have the radiological appearance of bone tumors but show no autonomic, stimulus-independent growth and can resolve spontaneously. In the majority of cases open biopsy is necessary to confirm the diagnosis. In some cases no surgical intervention is necessary (e.g. do not touch and leave me alone lesions), whereas in other cases the focus of treatment is on the prevention and therapy of pathological fractures as well as prevention of recurrence. CONCLUSION: Cystic bone formations are among the most commonly occurring non-traumatic bone lesions. To eliminate differential diagnostic unclarity, histological investigation of biopsy material is essential. In terms of surgical intervention there exists a trend towards multimodal therapy mostly based on a meticulous curretage.

Prospective quantitative assessment of spinal range of motion before and after minimally invasive surgical treatment of vertebral body fractures.

INTRODUCTION: Randomized clinical trials have generated doubts regarding the therapeutic effectiveness of spinal kyphoplasty to reduce pain and improve quality of life in patients with vertebral fractures. There is a paucity of data on the influence of kyphoplasty on spinal range of motion. To quantify early postoperative changes following kyphoplasty in spinal motion, a noninvasive, radiation-free measurement method was used and results related to clinical and radiological parameters. METHODS: The study group included 30 patients with an overall number of 54 symptomatic pathological vertebral compression fractures. All patients were treated with balloon kyphoplasty. Clinical results were recorded using the visual analog scale, SF 36, Roland Morris Score and the Oswestry Disability Index, at three time points; preoperative, 2 days postoperative, and at 12 weeks postoperative. The kyphosis angle/sagittal index were determined with biplanar X-rays. Amplitude/velocity of motion in extension/flexion was measured at each time point by use of the EpionicsSPINE(©) system (Epionics Medical GmbH; Potsdam, Germany) using two external sensor strips. RESULTS: Preoperative magnetic resonance imaging scans showed bone marrow edema in all vertebral bodies indicative of a recent, non-consolidated fracture. Pain and quality of life was significantly improved by kyphoplasty, both for the immediate postoperative period, as well as at 12 weeks postoperative. Radiological parameters also showed significant improvement following surgery. Total ROM did not significantly change 2 days after kyphoplasty, but amplitude and velocity were found to be increased 12 weeks postoperatively. Significant positive correlations were observed between increased range of motion and improved clinical/radiological scores. CONCLUSION: Significant clinical and radiological improvement following kyphoplasty supports the rational for cement augmentation in patients with pathological vertebral body fractures. To the knowledge of the authors, no prior study has assessed the influence of preservation and improvement of spinal range of motion on clinical outcome following kyphoplasty.