PARP-1 expression as a prognostic factor in Desmoid-type fibromatosis

Desmoid-type fibromatoses (or desmoid tumors) are entities of intermediate biological potential and are locally invasive. Radical surgery, as state of the art therapy, is frequently limited by incomplete resections. Hormone modifying therapies are promising but further research is required. Poly Adenosine Diphosphate Ribose Polymerase-1 (PARP-1), a DNA repairing enzyme, might be a pathogenetic factor and could become a potential target for therapy as shown by the successful treatment of selected carcinomas and sarcomas by PARP-inhibition. In this study, we investigated the expression of estrogen receptors (ER) α (1) and β (2), progesterone receptor (PR), androgen receptor (AR), as well as PARP-1 via immunohistochemistry and quantitative RT-PCR in 69 tissue samples of desmoid tumors. Immunohistochemistry was quantified using the Immunoreactivity Score (IRS). Overall expression patterns were correlated with clinical-pathologic parameters to determine their value as a prognostic factor. Among the investigated hormone receptors only ERβ showed partial cytoplasmic reactivity. PARP-1 revealed variable nuclear positivity with IRS ranging from 0 to 6. Univariate survival analysis showed that higher expression of estrogen receptor 1 was associated with shorter disease-free survival (p = 0.005). Uni- (p = 0.03) and multivariate (p = 0.003) analyses of mRNA data revealed that higher PARP-1 expression correlated with earlier recurrence. According to this study PARP-1 expression is associated with poorer prognosis, that is faster recurrence, highlighting the possibility of PARP-1-targeting agents as a therapeutic option. Hormone receptors were of minor prognostic relevance in this study.

Neoadjuvant chemotherapy plus radiation versus chemotherapy plus regional hyperthermia in high-grade soft tissue sarcomas: a retrospective comparison

PURPOSE

Localized adult high-grade soft tissue sarcomas (STS) usually require multimodality treatment including surgery, radiotherapy, chemotherapy and hyperthermia. If maximal preoperative tumor-shrinkage is envisaged, neoadjuvant chemotherapy + radiation (CRT) is often applied, however at the expense of relatively high toxicities and increased postoperative complication rates. This study aims to compare preoperative CRT with neoadjuvant chemotherapy + regional hyperthermia (HCT) regarding histopathological response, toxicity and outcome.

METHODS

In this retrospective analysis, 61 consecutive high-grade STS patients treated between 2009 and 2016 were included. All patients were treated within a prospective treatment protocol. 28 patients received neoadjuvant CRT 33 patients HCT. CRT consisted of four cycles doxorubicin/ifosfamide and two cycles ifosfamide concomitant to 50.4 Gray external beam radiotherapy. HCT consisted of 4-6 cycles doxorubicin/ifosfamide with deep regional hyperthermia administered bi-weekly during each cycle. Association of treatment modality with overall survival (OS), local control (LC) and freedom from distant metastases (FFDM) was evaluated by Kaplan-Meier and log-rank analyses.

RESULTS

The overall patient characteristics were well balanced. Histopathological tumor response did not differ significantly between both groups (p = .67), neither did higher-grade toxicities during neoadjuvant treatment. Wound dehiscence (p = .018) and surgical hospital re-admissions (p < .001) were both significantly more frequent in the CRT group. Two-year OS, LC and FFDM rates of all patients were 93, 85 and 71% with no significant differences between CRT and HCT.

CONCLUSION

Compared to CRT, HCT seems equally efficient and appears to bear less surgical complications. Interpretation should be cautious due to the low number of patients and the retrospective nature of this study.

Exome sequencing of osteosarcoma reveals mutation signatures reminiscent of BRCA deficiency

Osteosarcomas are aggressive bone tumours with a high degree of genetic heterogeneity, which has historically complicated driver gene discovery. Here we sequence exomes of 31 tumours and decipher their evolutionary landscape by inferring clonality of the individual mutation events. Exome findings are interpreted in the context of mutation and SNP array data from a replication set of 92 tumours. We identify 14 genes as the main drivers, of which some were formerly unknown in the context of osteosarcoma. None of the drivers is clearly responsible for the majority of tumours and even TP53 mutations are frequently mapped into subclones. However, >80% of osteosarcomas exhibit a specific combination of single-base substitutions, LOH, or large-scale genome instability signatures characteristic of BRCA1/2-deficient tumours. Our findings imply that multiple oncogenic pathways drive chromosomal instability during osteosarcoma evolution and result in the acquisition of BRCA-like traits, which could be therapeutically exploited.

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]

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.

[Solitary spinal metastases. Is aggressive surgical management justified?]

Advances in oncological and surgical therapies have led to a significant increase in life expectancy of cancer patients and also prolonged survival of patients with isolated or multiple metastases. Among the skeletal manifestations the spine is the most often affected site. Using novel imaging techniques with higher resolution and use of metabolic signatures, the screening of cancer patients has improved considerably. Consequently, the diagnosis of metastases is becoming increasingly more sensitive. Therefore, but also due to more effective polychemotherapy protocols, singular or solitary metastases are more frequently observed either in the early stages or as a result of a controlled malignant tumor entity (stable disease). The questions whether a solitary metastasis really exists (illusion or reality?) and its radical oncological and surgical treatment as a circumscribed singular tumor manifestation, is really relevant for the overall prognosis, remains controversial. However, it seems evident that a biologically favorable underlying tumor biology, radical treatment of the primary tumor and a long metastasis-free interval are valid predictors of a good oncological outcome. In the presence of a solitary metastasis under these circumstances (typical example: solitary metastasis of renal cell carcinoma many years after radical tumor nephrectomy) a radical surgical procedure (en bloc spondylectomy) can significantly improve the long-term prognosis of this patient group in combination with adjuvant chemotherapy and/or radiotherapy. However, a thorough evaluation of the overall survival prognosis, a detailed and complete staging followed by a treatment consensus in the interdisciplinary tumor board has to precede any therapeutical decisions.

Surgical management and outcome of skeletal metastatic disease of the humerus

PURPOSE OF THE STUDY Evaluation of outcome after surgical treatment of humerus metastases with a focus on tumour and patient derived factors, timing and strategy of intervention, surgical outcome and complications. MATERIAL AND METHODS Sixty-fie patients with a mean age of 64.3 years (range 25-89) with 66 metastases of the humerus were surgically treated in a 7-year time-period and retrospectively reviewed. RESULTS Renal cell carcinoma and breast cancer were the most abundant types of primary tumour. The mean time from diagnosis of primary tumour to fist metastasis was 14.5 months (range 0-173). The mean time from diagnosis of metastasis to surgery was 21.4 months (range 0-173). 38/28 intramedullary nails/locking plates were used for 58/8 manifest/impending pathological fractures. Mean cumulative survival was 16.3 months and implant failure rate was 6.1% with a mean time from initial surgery to revision of 22.2-20.6 months. CONCLUSIONS Our data indicate that treatment with intramedullary fiation or cement augmented plate osteosynthesis is successful for the vast majority of patients, but thorough clinical evaluation and precise decision making adapted to the patient's estimated life expectancy must be applied to avoid overtreatment or risk of implant failure. Key words: bone metastases, skeletal metastatic disease, humerus metastasis, pathologic fracture, impending fracture.

[Flap coverage of soft tissue defects after total knee arthroplasty]

Due to the marginal periarticular soft tissue envelope and the high risk of concomitant soft tissue or periprosthetic infection with the presence of exposed metal or bone, soft tissue defects after total knee arthroplasty are always a relevant surgical problem. Specific patient-related, intra- and postoperative risk factors have been identified and need to be considered during the course of treatment. Often a profound management of underlying infection must accompany the staged defect treatment which could require a prosthesis explantation with secondary revision in the case of a deep infection and involvement of the prosthesis. Four stages of soft tissue defects have been introduced (types A-D) and criteria for differentiation are the overall soft tissue coverage, the exposure, respectively, necrosis of the extensor mechanism, preservation or involvement of the joint capsule and/or an accompanying septic loosening of the prosthesis. The concept of plastic coverage follows a stage-adapted algorithm and includes secondary wound healing and mesh coverage for superficial defects, fasciocutaneous flaps for moderate defects and pedicled or free muscle flaps for deep defect situations with extension into the joint capsule. Crucial factors for a successful therapy include the early identification and precise analysis of defect characteristics, the careful preparation of the wound bed with serial debridements and the diligent flap coverage with early consultation of plastic-surgical expertise.

Radiofrequency ablation of osteoid osteomas: analgesia and patient satisfaction in long-term follow-up

PURPOSE

To review the long term clinical outcomes in the treatment of osteoid osteoma (OO) using radiofrequency ablation (RFA).

MATERIALS AND METHODS

Our retrospective study included 59 patients who were treated in the period from April 2001 to December 2012 due to a symptomatic OO using RFA. Here, the occurrence of complications and postoperative recurrence, as well as postoperative patient satisfaction were examined. Patients satisfaction was assessed by means of a telephone interview with the visual analogue scale (VAS).

RESULTS

Mean follow-up was 50 months (2 –116 months). The average size of the nidus was 6mm (range 2 – 14 mm). After initial radiofrequency ablation 11.8 % (7/59) of patient showed a recurrence of symptoms. Symptoms could successfully be treated by a second ablation in 5 patients. Assisted success rate was therefore 96.6 % (57/59). The complication rate was 5.1 % (2 major and one minor complication). Furthermore we report a very high patient satisfaction and acceptance of therapy.

CONCLUSION

RFA is a very successful therapy of symptomatic OOs with a high patient satisfaction.

KEY POINTS

Osteoid osteomas (OO) are rare benign bone tumors of the childhood and adolescence. Treatment of OOs with minimal-invasive radiofrequency ablation (RFA) shows a high patient satisfaction. RFA is by now the standard therapy of symptomatic OOs.

Radiofrequency ablation of osteoid osteomas: analgesia and patient satisfaction in long-term follow-up

PURPOSE

To review the long term clinical outcomes in the treatment of osteoid osteoma (OO) using radiofrequency ablation (RFA).

MATERIALS AND METHODS

Our retrospective study included 59 patients who were treated in the period from April 2001 to December 2012 due to a symptomatic OO using RFA. Here, the occurrence of complications and postoperative recurrence, as well as postoperative patient satisfaction were examined. Patients satisfaction was assessed by means of a telephone interview with the visual analogue scale (VAS).

RESULTS

Mean follow-up was 50 months (2 - 116 months). The average size of the nidus was 6 mm (range 2 - 14 mm). After initial radiofrequency ablation 11.8 % (7/59) of patient showed a recurrence of symptoms. Symptoms could successfully be treated by a second ablation in 5 patients. Assisted success rate was therefore 96.6 % (57/59). The complication rate was 5.1 % (2 major and one minor complication). Furthermore we report a very high patient satisfaction and acceptance of therapy.

CONCLUSION

RFA is a very successful therapy of symptomatic OOs with a high patient satisfaction.

KEY POINTS

▶ Osteoid osteomas (OO) are rare benign bone tumors of the childhood and adolescence. ▶ Treatment of OOs with minimal-invasive radiofrequency ablation (RFA) shows a high patient satisfaction. ▶ RFA is by now the standard therapy of symptomatic OOs.

[Multisegmental en bloc spondylectomy. Indications, staging and surgical technique]

OBJECTIVE

Description of the surgical technique including approaches and spinal reconstruction principles for patients scheduled for multilevel en bloc excision of vertebral tumors (multisegmental total en bloc spondylectomy) with the aim to attain tumor-free margins and minimize the risk of local and systemic tumor recurrence. Restoration of biomechanically sufficient spinal stability. Functional preservation and/or regaining of adequate neurological function.

INDICATIONS

Primary malignant and benign, aggressive spinal tumors. Solitary metastatic tumors of biologically and prognostically favorable primary tumor (good prognostic scores). Extracompartmental, multisegmental vertebral tumor manifestations according to Tomita type 6.

CONTRAINDICATIONS

Diffuse spinal/vertebral tumor spread according to Tomita type 7 (disseminated spinal metastatic disease). Detection of distant metastases in the staging investigation. Biologically unfavorable tumor entities or primary systemic malignant tumors/diffuse disseminated malignoma (Tomita score < 4-5 points, Tokuhashi score < 12 points).

SURGICAL TECHNIQUE

Depending on tumor growth, sequential performance of the anterior and posterior approach for local tumor release and preparation/replacement of encased large vessels. Posterior approach via dorsomedial incision and exposure of the posterior vertebral elements. Costotransversectomy, resection of the facets, resection of paravertebral rib segments. Laminectomy in the tumor-free lamina segment, resection of the ligamentum flavum and paradural ligation of affected nerve roots, bilateral ligation of the segmental arteries. Digital extrapleural palpation and dissection to the anterior vertebral body parts. Insertion of S-shaped spatulas ventral to the anterior aspect of the spine, and dissection of the disc spaces and the posterior longitudinal ligament. Instrumentation of pedicle screws and unilateral rod fixation, mobilization and careful, manual turning out/rotation of the affected vertebral segments around the longitudinal axis of the spinal cord. Interpositioning of a carbon-composite cage from posterior filled with autologous bone. Completion of the posterior stabilization, soft tissue closure, Goretex patch fixation if required in cases of chest wall resections.

POSTOPERATIVE MANAGEMENT

Intensive care monitoring with balanced volume replacement/transfusion. Postoperative adjuvant radiotherapy or chemotherapy, depending on the protocol and resection margins.

Identification of metastamirs as metastasis-associated microRNAs in clear cell renal cell carcinomas

MicroRNAs (miRNAs) play a pivotal role in cancerogenesis and cancer progression, but their specific role in the metastasis of clear cell renal cell carcinomas (ccRCC) is still limited. Based on microRNA microarray analyses from normal and cancerous samples of ccRCC specimens and from bone metastases of ccRCC patients, we identified a set of 57 differentially expressed microRNAs between these three sample groups of ccRCC. A selected panel of 33 miRNAs was subsequently validated by RT-qPCR on total 57 samples. Then, 30 of the 33 examined miRNAs were confirmed to be deregulated. A stepwise down-regulation of miRNA expression from normal, over primary tumor to metastatic tissue samples, was found to be typical. A total of 23 miRNAs (miR-10b/-19a/-19b/-20a/-29a/-29b/-29c/-100/-101/-126/-127/-130/-141/-143/-145/-148a/-192/-194/-200c/-210/-215/-370/-514) were down-regulated in metastatic tissue samples compared with normal tissue. This down-regulated expression in metastatic tissue in comparison with primary tumor tissue was also present in 21 miRNAs. In cell culture experiments with 5-aza-2'-deoxycytidine and trichostatin A, epigenetic modifications were shown as one reason of this down-regulation. The altered miRNA profiles, comprising newly identified metastasis-associated miRNAs, termed metastamir and the predicted miRNA-target interactions together with the significant correlations of miRNAs that were either lost or newly appeared in the studied sample groups, afford a solid basis for further functional analyses of individual miRNAs in RCC metastatic progression.

Surgical management of recurrent thoracolumbar spinal sarcoma with 4-level total en bloc spondylectomy: description of technique and report of two cases

INTRODUCTION

The descriptions of total spondylectomy and further development of the technique for the treatment of vertebral sarcomas offered for the first time the opportunity to achieve oncologically sufficient resection margins, thereby improving local tumor control and overall survival. Today, single level en bloc spondylectomies are routinely performed and discussed in the literature while only few data are available for multi-level resections. However, due to the topographic vicinity of the spinal cord and large vessels, the multisegmental resections are technically demanding, represent major surgery and only few case reports are available. Surgical options are even more limited in cases of revision surgery and local recurrences when en bloc spondylectomy was considered to be not feasible due to high risk of vital complications in expanding resection margins. Deranged anatomy, implants in situ and extensive intra-/paraspinal scar tissue formation resulting from previously performed approaches and/or radiation are considered the principal complicating factors that usually hold back spine surgeons to perform revision for resection leaving the patient to palliative treatment.

METHODS

We present two patient cases with previously performed piecemeal vertebrectomy in the thoracic spine due to a solitary high-grade spinal sarcoma. After extensive re-staging, both patients underwent a multi (4)-level en bloc spondylectomy in our department (one patient with combined en bloc lung resection). Except a local wound disturbance, there was no severe intra- or postoperative complication.

RESULTS

After multilevel en bloc spondylectomy both patients showed a good functional outcome without neurological deficits, except those resulting from oncologically scheduled resection of thoracic nerve roots. After a median follow-up of 13 months, there was no local recurrence or distant metastasis. The reconstruction using a posterior screw rod system that is interconnected to an anterior vertebral body replacement with a carbon composite cage showed no implant failure or loosening. In summary, the approach of a multilevel en bloc surgery for revision and oncologically sufficient resection in cases of spinal sarcoma recurrences seems possible. However, interdisciplinary decision making in a tumor board, realistic evaluation of surgical resectability to attain tumor free margins, advanced experiences in spinal reconstructions and involvement of vascular, visceral and thoracic surgical expertise are essential preconditions for acceptable oncological and functional outcome.

Expression of survivin detected by immunohistochemistry in the cytoplasm and in the nucleus is associated with prognosis of leiomyosarcoma and synovial sarcoma patients

Background

Survivin, a member of the inhibitor of apoptosis-protein family suppresses apoptosis and regulates cell division. It is strongly overexpressed in the vast majority of cancers. We were interested if survivin detected by immunohistochemistry has prognostic relevance especially for patients of the two soft tissue sarcoma entities leiomyosarcoma and synovial sarcoma.

Methods

Tumors of leiomyosarcoma (n = 24) and synovial sarcoma patients (n = 26) were investigated for their expression of survivin by immunohistochemistry. Survivin expression was assessed in the cytoplasm and the nucleus of tumor cells using an immunoreactive scoring system (IRS).

Results

We detected a survivin expression (IRS > 2) in the cytoplasm of 20 leiomyosarcomas and 22 synovial sarcomas and in the nucleus of 12 leiomyosarcomas and 9 synovial sarcomas, respectively. There was no significant difference between leiomyosarcoma and synovial sarcoma samples in their cytoplasmic or nuclear expression of survivin. Next, all sarcoma patients were separated in four groups according to their survivin expression in the cytoplasm and in the nucleus: group 1: negative (IRS 0 to 2); group 2: weak (IRS 3 to 4); group 3: moderate (IRS 6 to 8); group 4: strong (IRS 9 to 12). In a multivariate Cox's regression hazard analysis survivin expression detected in the cytoplasm or in the nucleus was significantly associated with overall survival of patients in group 3 (RR = 5.7; P = 0.004 and RR = 5.7; P = 0.022, respectively) compared to group 2 (reference). Patients whose tumors showed both a moderate/strong expression of survivin in the cytoplasm and a moderate expression of survivin in the nucleus (in both compartments IRS ≥ 6) possessed a 24.8-fold increased risk of tumor-related death (P = 0.003) compared to patients with a weak expression of survivin both in the cytoplasm and in the nucleus.

Conclusion

Survivin protein expression in the cytoplasma and in the nucleus detected by immunohistochemistry is significantly associated with prognosis of leiomyosarcoma and synovial sarcoma patients.

Bone sarcoma of the spine

Primary malignant bone tumors of the vertebral column, i.e., bone sarcomas of the spine, are inherently rare entities. Vertebral osteosarcomas and chordomas represent the largest groups, followed by the incidence of chondro-, fibro-, and Ewing's sarcomas. Detailed clinical and neurological examination, complete radiographic imaging [radiographs, computed tomography (CT), magnetic resonance imaging (MRI)], and biopsy are the decisive diagnostic steps. Oncosurgical staging for spinal tumors can serve as a decision-guidance system for an individual's oncological and surgical treatment. Subsequent treatment decisions are part of an integrated, multimodal oncological concept. Surgical options comprise minimally invasive surgery, palliative stabilization procedures, and curative, wide excisions with complex reconstructions to attain wide or at least marginal resections. The most aggressive mode of surgical resection for primary vertebral column tumors is the total en bloc vertebrectomy, i.e., single- or multilevel en bloc spondylectomy. En bloc spondylectomy involves a posterior or combined anterior/posterior approach, followed by en bloc laminectomy, circumferential (360 degrees) vertebral dissection, and blunt ventral release of the large vessels, intervertebral discectomy and rotation/ en bloc removal of the vertebra along its longitudinal axis. Due to the complex interdisciplinary approach and the challenging surgical resection techniques involved, management of vertebral bone sarcomas is recommended to be performed in specific musculoskeletal tumor centers.

MR-guided laser ablation of osteoid osteoma in an open high-field system (1.0 T)

Computed tomography is the standard imaging modality to minimize the extent of surgical or ablative treatment in osteoid osteomas. In the last 15 years, since a description of thermal ablation of osteoid osteomas was first published, this technique has become a treatment of choice for this tumor. We report the case of a 20-year-old man with an osteoid osteoma treated with laser ablation in an open high-field magnetic resonance imaging scanner (1.0 T). The tumor, located in the right fibula, was safely and effectively ablated under online monitoring. We describe the steps of this interventional procedure and discuss related innovative guidance and monitoring features and potential benefits compared with computed tomographic guidance.

[Postoperative manifestation of acute compartment syndrome by previously unknown heterozygote sickle cell anemia. A clinical case report]

Patients suffering from sickle cell disease show an increased ischemic intolerance due to continuous pro-inflammatory activation and dysfunction of the endothelium by recurrent vaso-occlusive episodes. The presented case shows the manifestation of a postoperative compartment syndrome of the lower leg following the intraoperative use of blood arrest in a patient with previously unknown sickle cell disease. Preexisting vulnerability for tissue hypoxia in patients at risk should be a major concern for intraoperative use of blood arrest during surgery of the extremities.

[Ventral stabilization of the lumbar spine of a 2-year-old boy with an expandable cage : 7-year course]

This case report describes the first implantation of an expandable cage into the lumbar spine of a 2-year-old boy. Due to incomplete remission of a teratoma, it was necessary to replace the second lumbar vertebral body with an expandable cage implantation and subsequent dorsoventral stabilization. During the follow-up period with annual x-ray examinations, a loss of correction without increased pain or neurological deficits could be shown in the now 9-year-old boy.

En bloc spondylectomy reconstructions in a biomechanical in-vitro study

Wide surgical margins make en bloc spondylectomy and stabilization a referred treatment for certain tumoral lesions. With a total resection of a vertebra, the removal of the segment's stabilizing structures is complete and the instrumentation guidelines derived from a thoracolumbar corpectomy may not apply. The influence of one or two adjacent segment instrumentation, adjunct anterior plate stabilization and vertebral body replacement (VBR) designs on post-implantational stability was investigated in an in-vitro en bloc spondylectomy model. Biomechanical in-vitro testing was performed in a six degrees of freedom spine simulator using six human thoracolumbar spinal specimens with an age at death of 64 (+/- 20) years. Following en bloc spondylectomy eight stabilization techniques were performed using long and short posterior instrumentation, two VBR systems [(1) an expandable titanium cage; (2) a connected long carbon fiber reinforced composite VBR pedicle screw system)] and an adjunct anterior plate. Test-sequences were loaded with pure moments (+/- 7.5 Nm) in the three planes of motion. Intersegmental motion was measured between Th12 and L2, using an ultrasound based analysis system. In flexion/extension, long posterior fixations showed significantly less range of motion (ROM) than the short posterior fixations. In axial rotation and extension, the ROM of short posterior fixation was equivalent or higher when compared to the intact state. There were only small, nonsignificant ROM differences between the long carbon fiber VBR and the expandable system. Antero-lateral plating stabilized short posterior fixations, but did not markedly effect long construct stability. Following thoracolumbar en bloc spondylectomy, it is the posterior fixation of more than one adjacent segment that determines stability. In contrast, short posterior fixation does not sufficiently restore stability, even with an antero-lateral plate. Expandable verses nonexpandable VBR system design does not markedly affect stability.

Three-dimensional stiffness in a thoracolumbar en-bloc spondylectomy model: a biomechanical in vitro study

BACKGROUND

In selected cases, en-bloc spondylectomy is the only option to reach wide resection margins for patients with malignant tumours of the thoracolumbar spine. These patients must be also provided a secure initial stabilization of the spine and this is the role of vertebral body replacements employed with posterior fixation systems. The aim of this study was to determine the postimplantation stiffness of a connected vertebral body replacement pedicle screw system in different implantation scenarios following an en-bloc spondylectomy. Reconstruction was varied by posterior fixation lengths and axial compression forces during implantation.

METHODS

Three-dimensional stiffness was assessed in 6 fresh frozen human spinal specimens (Th11-L3) using a six degree of freedom spine simulator. Following en-bloc spondylectomy reconstruction was performed using a carbon composite fibre vertebral body replacement connected to a posterior fixation system by two artificial pedicles. The spines were loaded with pure moments (7.5Nm) in the three main motion planes. The intersegmental rotations were measured between Th12 and L2.

FINDINGS

Reconstructions using long posterior fixation modes demonstrated significant (P<0.05) higher stiffness compared to short posterior fixations in all motion planes. In axial rotation short posterior fixation modes failed to reach the values of the intact state. Neither high nor low axial compression force during implantation showed a significant impact on postfusional stiffness.

INTERPRETATION

In this biomechanical model, the employed system should be implanted with a posterior fixation of two adjacent segments to the lesion in order to achieve a secure stabilization of the treated segment.

[A prospective two-year follow-up of thoracic and lumbar osteolytic vertebral fractures caused by multiple myeloma treated with balloon kyphoplasty]

PURPOSE

Balloon kyphoplasty is a minimally invasive procedure for the stabilization of osteoporotic and osteolytic vertebral fractures. The purpose of this prospective study was to evaluate this operative procedure in the treatment of osteolytic vertebral fractures with regard to the reduction of pain and functional improvement of the patients and further to evaluate the restoration of vertebral height postoperatively.

MATERIALS AND METHODS

In this study 26 patients (21 male, 5 female) with osteolytic vertebral fractures were treated with balloon kyphoplasty. In total, 59 vertebral fractures were treated with balloon kyphoplasty. Preoperatively conventional radiographs in lateral and a. p. views, CT and/or MRI were preformed. Pre- and postoperatively the clinical parameters using VAS (visual analogue scale) and the Oswestry score were evaluated. Radiographic scans were performed pre- and postoperatively and after 3, 6, 12 and 24 months. The vertebral height and endplate angles were measured.

RESULTS

The median pain scores (VAS) decreased from pre- to post-treatment significantly (p < 0.05) as also did the Oswestry score (p < 0.05). Balloon kyphoplasty led to a significant and sustained reduction of pain resulting in a significant functional improvement for the patients. A significant restoration of vertebral height and reduction of the kyphotic angle could be achieved with the balloon technique (p < 0.05). Furthermore, the minimal-invasive procedure was able to stabilize the spine also over a longer period of 24 months. A radiation therapy and/or chemotherapy could be performed without loss of time.

CONCLUSION

In the treatment of osteolytic vertebral fractures balloon kyphoplasty led to a quick and sustained reduction of pain and as well as a functional improvement for the patients. A restoration of the vertebral height and reduction of the kyphotic angle was especially attributable to the balloon technique. The balloon kyphoplasty was able to stabilize the fractured vertebrae in the long-term and was able to prevent an increase of kyphotic deformity. Balloon kyphoplasty is an outstanding alternative in comparison to the established therapeutic concepts in the treatment of osteolytic vertebral fractures.

Chirurgisches Management von Wirbelsäulenmetastasen

The spine is the most frequent site of skeletal metastases. Among all spinal malignancies metastatic disease is most frequent and indicative of disseminating tumor disease. Depending on primary tumor entity, estimated survival time, general health status of the patient, presence of spinal instability and neurological deficits an oncological useful and patient-specific therapeutic intervention should be performed. New anterior approaches, resections and reconstruction techniques are making surgery a preferred method over radiation therapy. For differential indication of the multiple surgical treatment modalities prognostic scores are available to assist individual decision making. Indications for surgery include survival prognosis of minimum 3 months, intractable pain, progress of myelon compression and/or neurological deficits under radiochemotherapy, spinal instability and necessity for histological diagnosis. Resulting quality of life depends on efficient decompression of the spinal cord and restoration of spinal stability. To achieve these ultimate goals there are different anterior and posterior approaches, instrumentations and vertebral body replacement implants available. Preoperative embolization should be performed in hypervascular tumors, e.g., renal cell cancer. Vertebro-/Kyphoplasty as a percutaneous intervention should be considered for painful multisegmental disease and symptomatic osteolysis without epidural tumor compression to reach analgesia and stability. A multidisciplinary approach in patient selection, decision making and management is an essential precondition for complication avoidance and acceptable quality of life.

Balloon kyphoplasty for the treatment of pathological fractures in the thoracic and lumbar spine caused by metastasis: one-year follow-up

PURPOSE

To evaluate the clinical and radiographic outcomes of balloon kyphoplasty in patients with fractures of the thoracic and lumbar spine caused by metastatic disease.

MATERIAL AND METHODS

64 balloon kyphoplasty procedures were performed in 31 patients (18 females and 13 males with bone metastasis), 28 of whom were followed up over a period of 1 year. Symptomatic levels were identified by clinical presentation, magnetic resonance imaging (MRI), radiographs, and computed tomography (CT). In the prospective 1-year follow-up, visual analog scale (VAS) and Oswestry Disability Score were documented. Radiographs were performed pre- and postoperatively, and at 3, 6, and 12 months. Vertebral height and kyphotic deformity were measured to assess restoration of the sagittal alignment.

RESULTS

The median pain scores (VAS) decreased significantly (P<0.05) from pre- to post-treatment, as did the Oswestry Disability Score (P<0.05). Polymethyl methacrylate (PMMA) cement leakage was detected in eight of 64 vertebral bodies (12.5%), but did not have any clinical relevance. During 1-year follow-up, balloon kyphoplasty stabilized vertebral height and prevented further kyphotic deformity.

CONCLUSION

Balloon kyphoplasty is an effective, minimally invasive procedure for the stabilization of pathological vertebral fractures caused by osteolytic lesions of vertebral bodies due to metastatic disease. It gives a statistically significant reduction of pain and prevents further kyphotic deformity of the spine.

Primary malignant bone tumors and solitary metastases of the thoracolumbar spine: results by management with total en bloc spondylectomy

Primary malignant spinal tumors and solitary vertebral metastases of selected tumor entities in the thoracolumbar spine are indications for total en bloc spondylectomy (TES). This study aimed to describe our oncological and surgical management and to analyze the treatment results by management with TES for extra- and intracompartmental solitary spinal metastases and primary malignant vertebral bone tumors. In 15 patients (3 malignant bone tumors and 12 solitary metastases), tumors were distributed in the thoracic (n = 8) and lumbar (n = 7) spine. Tumors were classified as intra- (n = 8) and extracompartmental (n = 7). All patients underwent TES via a laterally extended posterior approach followed by dorsoventral reconstruction. Function and quality of life were assessed by Oswestry disability index (ODI) and SF-36 score. At follow-up (100%; mean: 33 +/- 22 months), 11 patients had no evidence of disease. Two patients were alive with the disease and two were dead of the disease (no primary bone tumors). Histology revealed negative margins (R0) in all patients with wide (n = 11) and marginal (n = 4) resections. Two patients developed pulmonal metastases of which they died at 4 and 16 months of survival. No local recurrence was observed. Major complications did not occur. TES resulted in an acceptable outcome in the quality of life and function. TES is a demanding procedure reaching wide to marginal resections in a curative approach. In conjunction with multimodal therapies, local recurrences can effectively be prevented while control of distant disease needs to be improved. Proper selection of adequate patients combined with careful surgical planning are prerequisites for low complication rates, acceptable function and improved overall prognosis.

Local cooling restores microcirculatory hemodynamics after closed soft-tissue trauma in rats

BACKGROUND

Severe closed soft-tissue injury (CSTI) results in progressively developing microvascular dysfunction and local inflammation. Cooling reduces swelling, pain, cellular oxygen demand, and metabolic activity. However, effects of cooling on posttraumatic microcirculation are not yet fully understood. Thus, we assessed effects of local cooling on microcirculation, regional inflammatory response including leukocyte-endothelial cell interaction, and edema formation after CSTI.

METHODS

Standardized CSTI was induced by means of controlled impact injury in the left tibial compartment of 14 male Sprague-Dawley rats. Rats were assigned to four groups (n = 7 per group) as follows: group I, no trauma/no cooling; group II, no trauma/20 minutes of cooling; group III, 1.5 hours posttrauma/no cooling; and group IV, 1.5 hours posttrauma/20 minutes of cooling.

RESULTS

CSTI resulted in a significant decrease in functional capillary density, a marked increase in microvascular permeability, and granulocyte infiltration (HIS48) as revealed by intravital microscopy and immunohistochemistry of the left extensor digitorum longus muscle. After 20 minutes of local cooling, these microvascular derangements were restored to the level of controls (group I). Edema (extensor digitorum longus muscle wet-to-dry weight ratio) was less pronounced compared with noncooling conditions (group III). Immunoreactivity for HIS48 (neutrophilic granulocytes) in injured rats subjected to local cooling (group IV) was markedly decreased compared with noncooling conditions (group III).

CONCLUSION

These results provide in vivo evidence that cooling affords protection of posttraumatic microcirculation through sustained inhibition of microvascular and endothelial dysfunction leading to less granulocyte-dependent inflammation and skeletal muscle edema. Local cooling appears to reduce propagation of acute microvascular injury, preventing leukocyte-dependent tissue destruction and escalation of secondary tissue damage after musculoskeletal soft-tissue trauma.

Maintained pain reduction in five patients with multiple myeloma 12 months after treatment of the involved cervical vertebrae with vertebroplasty

PURPOSE

To evaluate in a prospective study the clinical and radiographic outcome of vertebroplasty in patients with osteolytic lesions of the cervical spine caused by multiple myeloma.

MATERIAL AND METHODS

Pathological vertebral fractures associated with multiple myeloma were treated in five patients. Vertebroplasty was performed in 12 vertebral bodies. Symptomatic levels were identified by correlating the clinical presentation with magnetic resonance imaging (MRI), conventional radiographs, and computed tomography (CT). During the 12-month follow-up, pain symptoms were measured on a self-reported visual analog scale (VAS), neck pain disability index (NPDI, range 0-100%), and cervical spine functional score (CSFS, range 0-100). Medical imaging was performed pre- and postoperatively and after 3, 6, and 12 months. The vertebral height was measured to assess the restoration of the sagittal alignment.

RESULTS

The median pain scores (VAS) as well as the NPDI and CSFS decreased significantly after vertebroplasty (P<0.05). Cement leakage occurred in two of 12 vertebral bodies (16.6%), without clinical relevance. The vertebral body height was stabilized during follow-up.

CONCLUSION

Vertebroplasty in the cervical spine is an effective open surgical procedure for the stabilization of pathological vertebral fractures caused by multiple myeloma leading to a statistically significant reduction of pain status. Vertebral body height is stabilized and further deformities are avoided.

Percutaneous balloon kyphoplasty in the treatment of pathological vertebral body fracture and deformity in multiple myeloma: a one-year follow-up

PURPOSE

To evaluate the clinical and radiographic outcomes of balloon kyphoplasty in patients with fractures of the thoracic and lumbar spine caused by multiple myeloma.

MATERIAL AND METHODS

Vertebral fractures due to multiple myeloma were treated by balloon kyphoplasty (20 patients, 48 vertebral bodies). Symptomatic levels were identified by clinical presentation, magnetic resonance imaging (MRI), radiographs, and computed tomography (CT). During the following year, visual analog scale (VAS) and Oswestry disability score were documented. Radiographs were taken pre- and postoperatively at 3, 6, and 12 months. Vertebral height and kyphotic deformity were measured to assess restoration of the sagittal alignment.

RESULTS

The median pain scores (VAS) decreased significantly from pre- to posttreatment, as did the Oswestry disability score (p < 0.05). Clinically asymptomatic cement leakage occurred at 5 fracture levels (10.4%). During 1-year follow-up, this surgical technique demonstrated restoration and stabilization of the height of the vertebral body.

CONCLUSION

Balloon kyphoplasty is an effective minimally invasive procedure for stabilizing pathological vertebral fractures caused by multiple myeloma and leading to a statistically significant reduction of pain status. Balloon kyphoplasty stabilizes the vertebral body height, but is only partially able to prevent further kyphotic deformities.

Managementprobleme in Diagnostik und Therapie der pathologischen Schenkelhalsfraktur

Pathological fractures caused by primary bone tumours are rare compared with fractures evolving in response to general osteoporosis or bone metastases. Nevertheless in cases of fracture due to inadequate trauma the underlying causality has to be clarified including histological analysis prior to the operating procedure. This case report demonstrates diagnostic and therapeutic standards in cases of pathological fracture of the proximal femur caused by osteosarcoma.

Osteoid Osteoma: Experience with Laser- and Radiofrequency-Induced Ablation

The purpose of this study was to analyze the clinical outcome of osteoid osteoma treated by thermal ablation after drill opening. A total of 17 patients and 20 procedures were included. All patients had typical clinical features (age, pain) and a typical radiograph showing a nidus. In 5 cases, additional histological specimens were acquired. After drill opening of the osteoid osteoma nidus, 12 thermal ablations were induced by laser interstitial thermal therapy (LITT) (9F Power-Laser-Set; Somatex, Germany) and 8 ablations by radiofrequency ablation (RFA) (RITA; StarBurst, USA). Initial clinical success with pain relief has been achieved in all patients after the first ablation. Three patients had an osteoid osteoma recurrence after 3, 9, and 10 months and were successfully re-treated by thermal ablation. No major complication and one minor complication (sensible defect) were recorded. Thermal ablation is a safe and minimally invasive therapy option for osteoid osteoma. Although the groups are too small for a comparative analysis, we determined no difference between laser- and radiofrequency-induced ablation in clinical outcome after ablation.

Giant cell tumors of the bone: Molecular profiling and expression analysis of Ephrin A1 receptor, Claudin 7, CD52, FGFR3 and AMFR

Giant cell tumors (GCTs) of the bone are osteolytic neoplasms with variable degrees of aggressiveness. The aim of this study was the molecular characterization of GCT tissue. We established gene expression profiles and discovered a number of genes that have not been described in GCTs before. RNA was prepared from 7 cryopreserved GCTs (primary tumors n = 5, relapses n = 2) and was hybridized to Affymetrix HG U133A microarrays. Paraffin-embedded samples were used for immunohistochemical validation (primary tumors n = 16, relapses n = 6). Gene ontology revealed that the majority of genes, found to be differentially expressed between primary and recurrent GCTs, were associated with receptor tyrosine kinase activity. We selected one upregulated gene (Claudin 7) and four downregulated genes (CD52, Ephrin A1 receptor, autocrine motility factor receptor [AMFR] and fibroblast growth factor receptor 3 [FGFR3] for further analysis using immunohistochemistry. Immunohistochemical analysis of CD52, AMFR, and Ephrin A1 receptor revealed expression profiles concordant with the microarray data, also with regard to differences between primary tumors and relapses.

[60 year old patient with soft tissue infection of the right leg]

Group A streptococcal necrotizing fasciitis is a rare disease associated with high mortality. Since severe toxic shock syndrome is a common complication, only immediate and aggressive surgical intervention, adequate antimicrobial therapy and supportive intensive care can be life-saving. We report about successful treatment of a 60-year old patient with necrotizing fasciitis and multiple organ failure.

Acute effects of N-acetylcysteine on skeletal muscle microcirculation following closed soft tissue trauma in rats

Trauma-induced microcirculatory dysfunction, formation of free radicals and decreased endothelial release of nitric oxide (NO) contribute to evolving tissue damage following skeletal muscle injury. Administration of N-acetylcysteine (NAC) known to scavenge free radicals and generate NO is considered a valuable therapeutic approach. Thus, the objective of this study was to quantitatively analyze the acute effects of NAC on skeletal muscle microcirculation and leukocyte-endothelial cell interaction following severe standardized closed soft tissue injury (CSTI). Severe CSTI was induced in the hindlimbs of 14 male anesthetized Sprague-Dawley rats using the controlled impact injury technique. Rats were randomly assigned (n = 7) to high-dose intravenous infusion of NAC (400 mg/kg body weight) or isovolemic normal saline (NS). Non-injured, sham-operated animals (n = 7) were subjected to the same surgical procedures but did not receive any additional fluid. Creatin kinase (CK) activity was assessed at baseline, 1 h before and 2 h following posttraumatic NAC or NS infusion. Microcirculation of the extensor digitorum longus (EDL) muscle was analyzed using intravital microscopy and Laser-Doppler flowmetry (LDF). Edema index (EI) was calculated by measuring the EDL wet-to-dry weight ratio (EI=injured/contralateral limb). EDL-muscles were analyzed for desmin immunoreactivity and granulocyte infiltration. Microvascular deteriorations observed following NS-infusion were effectively reversed by NAC: Functional capillary density was restored to levels found in sham-operated animals and leukocyte adherence was significantly (p < 0.05) reduced compared to the NS group. NAC significantly (p < 0.05) increased erythrocyte flux determined by Laser-Doppler flowmetry. Posttraumatic serum CK levels and EI were significantly (p < 0.05) decreased by NAC. During the posttraumatic acute phase, single infusion of NAC markedly reduced posttraumatic microvascular dysfunction, attenuated both leukocyte adherence and tissue infiltration. NAC also decreased CSTI-induced edema formation and myonecrosis as reflected by attenuated serum CK levels and attenuated loss of desmin immunoreactivity. NAC may serve as an effective therapeutic strategy by supporting microvascular blood supply and tissue viability in the early posttraumatic period. Additional studies aimed at long-term analysis and investigation of injury severity--or dosage dependency are needed.

[Interdisciplinarity in reconstructive surgery of the extremities]

From the perspective of trauma and orthopedic surgery interdisciplinary reconstructive surgery of the extremities encompasses different indications ranging from IIIB/Copen fractures with major segmental loss of bone and soft tissue, to arterial vessel in-jury necessitating vascular repair and to biological, plastic reconstructions following resections of musculoskeletal tumors. The interdisciplinary treatment concept including trauma-orthopedic surgery combined with vascular, plastic and neuro- as well as microsurgery has significantly decreased amputation rates and functional deficits thereby improving quality of life and long-term oncological outcome The multisdisciplinary management of both complex trauma and malignant bone/ soft tissue sarcoma of the extremity is an integral task of the surgical trauma or tumor center. Close interdisciplinary communication and expierence are the precondition for performance of a priority-adapted therapeutic strategy, low complication rates and improvement of overall prognosis.

[CT and fluoroscopy based navigation in pelvic surgery]

Navigation procedures based upon CT data were introduced into spine surgery in 1994. Since then the method has been used in other areas, such as joint replacement, reconstructive surgery and tumor surgery, because of its high precision and reduced radiation exposure. The original CT-based spine module can be adapted for pelvic surgery with the prerequisite, that the positioning of the fragments is identical in CT and at operation; otherwise, a new data set has to be acquired. The experience with CT-based navigation in pelvic surgery will be explained in the context of five percutaneous screw fixations and three tumor resections. The technique will be described. The fluoroscopy-based navigation has been used in trauma surgery since the late 1990 s. Since than the method has gained wide acceptance in the field of joint replacement and reconstructive surgery as well. Between June 2000 and December 2002 we performed 36 percutaneous screw fixations in the pelvis with postoperative X-ray and CT control. Thirty five of the 36 screws were placed correctly. In one screw an anterior cortex perforation of the sacrum was seen on CT, but without neurological consequences. Based upon our clinical experience we believe that CT-based navigation is indicated in screw fixations for minimally displaced pelvic injuries or dysplasia and, with increasing importance, in tumor surgery. Fluoroscopy based navigation with adequate image quality is the method of choice for SI screw fixations in traumatic or degenerative instabilities, especially if an update of the images is needed.

Operative Interdisziplinarit�t?Extremit�ten

Interdisciplinary reconstructive surgery of the extremities involves a variety of indications ranging from IIIB/C open fractures with major segmental loss of bone and soft tissue, to arterial vessel injury necessitating vascular repair, and to biological, plastic reconstruction following resection of musculoskeletal tumors. The multidisciplinary approach involving trauma/orthopedic surgery combined with vascular, plastic, and neuro- resp. microsurgery has significantly increased the rate of limb-sparing operations and improved morbidity, function, quality of life, and long-term oncological outcome. The multidisciplinary treatment of both complex trauma and malignant bone/soft tissue sarcoma of the extremity is an integral task of surgical trauma and tumor centers. Close interactive communication between the individual surgical disciplines has decisively influenced prognosis and is the precondition for priority-adapted therapeutic strategies.

Three different stages of bone stress reactions of long bones in one patient: case report and review of the literature

INTRODUCTION

The similar clinical and radiological early course of stress fractures and bone tumors can lead to diagnostic misinterpretation.

MATERIALS AND METHODS

A patient is presented who was admitted to our clinic with the diagnosis of similar bone tumors in the distal femur and the proximal tibia. We found an additional localization with high bone turnover in the contralateral proximal tibia; including this lesion, the patient presented with three different types of stress reaction of bone. The final diagnostic decision-making was based on MRI and bone scintigraphy as well as the consideration of localization, age of occurrence, and behavior of malignant bone diseases. Therefore, bone biopsy was not performed.

RESULTS

After 8 weeks of partial weight-bearing, the symptoms disappeared, and the patient could return to normal activity.

Unknown AV-fistula as reason for post-traumatic hematoma of the thigh

A case is reported of a 28-year-old patient with gradually developing massive swelling of the right thigh after sustaining a blunt trauma. 3 1/2 months after the injury, surgery was performed because of a persisting tumor at the thigh. Intraoperatively, massive bleeding occurred, the bleeding vessel was sutured. Postoperative angiography disclosed arteriovenous (av) fistulae from the internal iliacal artery to a gluteal vein as source for the bleeding. The feeding artery was closed by coiling, the patient recovered completely. To the authors' knowledge, development of an av-fistula following blunt trauma has not been described previously. Similarly, the differential diagnosis of a posttraumatic bleeding of a congenital av-malformation was not yet reported. The authors emphasize, that prior to the surgery of inadequately behaving hematomas, an angiography should be performed.

[Treatment concepts of benign bone tumors and tumor-like bone lesions]

The indications for surgical treatment of benign bone tumors and tumor-like lesions depend on the biological activity, clinical symptoms and anatomic location of the the lesion. Clinically silent lesions ("leave me alone Lesions") lacking any scintigraphic enhancement and without danger of pathologic fracture or malign transformation only need surveillance and do not require surgery.However, tumors becoming symptomatic, displaying progression after termination of skeletal growth or radiographic signs of malignancy should be scheduled for surgical intervention. For most benign tumors intralesional curettage and subsequent bone grafting is the treatment of choice, maintaining structural integrity and functional stability of the bone and adjacent joint. In case of uncertain histopathological diagnosis an open biopsy should be performed followed by definitive either marginal or en-bloc resection, preferably at a single procedure. Depending on the tumor-specific risk of recurrence, adjuvant measures as phenol instillation or cryotherapy using liquid nitrogen may additionally be applied. As for the unicameral juvenile bone cyst or osteoid osteoma alternative minimal invasive techniques like corticoid injection and CT-guided percutaneous eradication of the nidus have been successfully introduced into clinical practice. Depending on the activity of the tumor recurrent lesions are recommended to be treated by marginal or enbloc resection. The radical and aggressive mode of surgical therapy has to be balanced with the treatment-related morbidity, i.e. complication rate, possibilities for reconstructive stabilizations and resultant functional deficits,making the decision a responsible challenge to the orthopedic surgeon.

Treatment of complex proximal humeral fractures with minimally invasive fixation of the humeral head combined with flexible intramedullary wire fixation - introduction of a new treatment concept

The treatment of three- or 4-part proximal humerus fractures is still a matter of scientific discussion. The following study presents the results of a combined procedure using limited invasive fixation techniques for reconstruction of the humerus head and retrograde intramedullary wiring with elastic nails for the treatment of displaced three- or 4-part fractures. A prospective study of 24 patients with 3-part and 4-part fractures was performed from September 1995 to December 1998. Combined biologic fixation for reconstruction of the humerus head, including intramedullary wiring, was utilized. Fracture reduction was performed in an open soft-tissue-preserving technique through a limited lateral approach. Fixation of the head fragments was performed using screw and/or cerclage wire fixation. The reconstructed humerus head was stabilized to the shaft with intramedullary wires, with retrograde insertion 2 cm above the olecranon fossa. Supportive fixation of the head fragments was achieved using fully threaded cancellous screws. At the 1-year postoperative follow-up, 40% of the 18 patients had excellent results using the Neer and Constant score. Forty-five percent had satisfactory and 15% unsatisfactory results. The initial results of this study reveal that a combination of limited internal fixation of the humerus head and retrograde elastic intramedullary wiring provide stable fixation with limited soft-tissue destruction. This approach has been shown to be especially useful for the combined treatment of three- or four-part fractures of the humeral head.