Characteristics and outcome of infections associated with tumor endoprostheses

Introduction: Infection associated with prosthesis used after tumor resection is a common and serious complication. The purpose of the current retrospective study was to describe the course of infection in patients with a tumor endoprosthesis and the determination of risk factors associated with failed limb salvage. Material and Methods: 30 patients with an infection associated with a tumor endoprosthesis were investigated with regard to treatment strategies, number and type of revision operations, duration of hospital stay, determination of risk factors associated with failed limb salvage and final outcome. Results: Limb salvage related to the complication infection was achieved in 19 patients (63.3%). Two-stage reimplantation of an endoprosthesis was successful in 14 patients but subsequently failed in one patient. Out of 11 patients where limb salvage failed, an amputation was performed in 6 patients, a rotationplasty in 4, and stump lengthening procedure in 1 patient. A poor soft tissue condition was a significant (P<0.05) risk factor for failed limb salvage. No patient receiving chemotherapy with a poor soft tissue condition had limb salvage surgery. The mean number of revision operations per patients was 2.6. The mean duration of hospital stay was 68 days. Conclusion: Infection associated with prosthesis is a serious complication and is involved with long hospitalization. Limb salvage failed mostly in the case of a poor soft tissue condition. In these cases repeated revision surgery should be avoided and ablative surgery recommended at an early stage. Rotationplasty is an alternative to amputation in the case of an infection of the proximal or distal part of the femur.     

Treatment and outcome of giant cell tumors of the pelvis: 20 cases followed for 1 to 11 years

Background and purpose Giant cell tumors (GCTs) of bone rarely affect the pelvis. We report on 20 cases that have been treated at our institution during the last 20 years.Methods 20 patients with histologically benign GCT of the pelvis were included in this study. 9 tumors were primarily located in the iliosacral area, 6 in the acetabular area, and 5 in the ischiopubic area. 8 patients were treated by intralesional curettage and 6 by intralesional resection with additional curettage of the margins. 3 patients with iliacal tumors were treated by wide resection. 2 patients were treated by a combination of external beam irradiation and surgery, and 1 patient solely by irradiation. In addition, 9 patients received selective arterial embolization one day before surgery. Of the 6 patients with acetabular tumors, 1 secondarily received an endoprosthesis and 1 was primarily treated by hip transposition. The patients were followed for a median time of 3 (1–11) years.Results 1 patient with a pubic tumor developed a local recurrence 1 year after intralesional resection and additional curettage of the margins. The recurrence presented as a small soft tissue mass within the scar tissue of the gluteal muscles and was treated by resection. No secondary sarcoma was detected and none of the patients developed pulmonary metastases or multicentricity. No major complication occurred during surgery.Interpretation We conclude that most GCTs of the pelvis can be treated by intralesional procedures. For tumors of the iliac wing, wide resection can be an alternative. Surgical treatment of tumors affecting the acetabular region often results in functional impairment. Pre-surgical selective arterial embolization appears to be a safe procedure that may reduce the risk of local recurrence.     

Proximal fibula resection in the treatment of bone tumours

Background and objectives

We present a large study of patients with proximal fibula resection. Moreover we describe a new classification system for tumour resection of the proximal fibula independent of the tumour differentiation.

Methods

In 57 patients the functional and clinical outcomes were evaluated. The follow-up ranged between six months and 22.2 years (median 7.2 years). The indication for surgery was benign tumours in ten cases and malignant tumours in 47 cases. In 13 of 45 patients, where a resection of the lateral ligament complex was done, knee instability occurred. In 32 patients a resection of the peroneal nerve with resulting peroneal palsy was necessary.

Results

Patients with peroneal resection had significantly worse functional outcome than patients without peroneal resection. An ankle foot orthosis was tolerated well by these patients. Three of four patients with pathological tibia fracture had local radiation therapy. There was no higher risk of tibia fracture in patients with partial tibial resection.

Conclusions

Resection of tumours in the proximal fibula can cause knee instability, peroneal palsy and in cases of local radiation therapy, a higher risk of delayed wound healing and fracture. Despite the risks of proximal fibula resection, good functional results can be achieved.     

The influence of the alloy of megaprostheses on infection rate

We retrospectively reviewed 197 patients who underwent reconstruction with a megaprosthesis of the lower extremity. A cobalt-chrome alloy system was used in 77 patients and a titanium alloy system in 120 patients. The overall infection rate was 20.8% (n = 41). Separated into the 2 prosthesis systems used, an infection rate of 31.2% was found in the patients with a cobalt-chrome-alloy prosthesis and 14.2% in the titanium alloy group of patients (P < .01). Early infection occurred in 5.1% (n = 10) and late infection in 15.7% (n = 31). Selecting 2 identical subgroups for further analysis, the cobalt-chrome alloy prostheses were associated with a significantly higher infection rate, with 5 infections of 26 megaprostheses vs 1 infection of 36 titanium megaprostheses (P < .05).     

The Burch–Schneider cage for reconstruction after metastatic destruction of the acetabulum: outcome and complications

Introduction  

The Burch–Schneider cage is an established implant in revision surgery after hip arthroplasty that is used for reconstructing osseous defects in the acetabulum. However, there are only a few reports about the use of cages in patients with metastatic destruction of the acetabulum. The aim of this retrospective study was to assess the outcome and complications of this procedure.     

Benigne Knorpeltumoren

Background

The majority of benign bone tumors are cartilage tumors. Most common are enchondroma and osteochondroma. Often they represent incidental findings in radiological diagnostics. Thus, the incidence of cartilage tumors is unknown, as most of them are never diagnosed due to the absence of any symptoms.

Objectives

This article describes the diagnostic and therapeutic approach of benign cartilage tumors, focusing on incidental findings.

Methods

The current knowledge and our own experience in the diagnostics and treatment of benign condroid tumors are presented.

Results

As enchondroma represent most often the classic incidental finding without any symptoms or clinical findings, osteochondroma are often diagnosed in young patients by clinical examination showing a painless swelling that can increase in size according to skeletal growth. Most of these asymptomatic enchondroma and osteochondroma are so called “leave me alone lesions” and do not need any treatment, while other benign tumors (e.g., atypical cartilage tumors, chondroblastoma, chondromyxoidfibroma or osteochondroma with a cartilage cap of over 2 cm) need surgical treatment. These active or local aggressive tumors must be differentiated from the “leave me alone lesions”. Additionally, patients with syndromes like Ollier disease (enchondromatosis), Maffucci syndrome or hereditary multiple exostosis must be examined and checked carefully as malignant degradation is possible.

Conclusion

As most cartilage tumors are benign and remain benign, inappropriate diagnostics or operative treatment just to provide security is obsolete. Plain X-ray is often enough for follow-up and other modalities only become necessary when symptoms occur.     

Rekonstruktion knöcherner Defekte in der Knochensarkomchirurgie

Background

Primary bone sarcomas typically arise in the long bones and the pelvis of children and adolescence but may also occur in adults. Meta/diaphysial tumour involvement resulting in the necessity of a joint replacement is more common than diaphysial tumour sites.

Aim

In the treatment of these tumours, both endoprosthetic replacement and biological reconstruction techniques are used. Each technique has method-specific advantages and disadvantages.

Results

To choose the appropriate surgical method, a multitude of influencing parameters need to be considered. The age at treatment (soft tissue situation/estimated growth/biological potential of the bone), therapeutic concept (palliative vs. curative), the tumour site (upper/lower extremity), tumour expansion (diaphysis/metaphysis) and oncological treatment concept (chemotherapy/radiotherapy) are key factors significantly influencing the surgical technique in terms of functional outcome and longevity of the reconstruction.

Conclusion

Surgical treatment of bone sarcoma requires broad-based experience of the oncological surgeon. Knowledge of the different surgical technics and reconstruction methods is decisive to offer the individual patient the best oncological and functional outcome.     

Knorpelbildende Knochentumore

Primary malignant bone tumours are rare. The annual incidence of these tumours is 10 per 1 million. Nearly 30% of the primary malignant bone tumours are malignant cartilage tumours. The frequency of benign cartilage tumours cannot be definitely estimated because these tumours are normally clinically inapparent and therefore often diagnosed as an incidental finding. The cartilage tumours appear as benign lesions (e.g. chondroma), as borderline tumours (proliferative chondroma vs grade I chondrosarcoma) or as highly malignant chondrosarcoma (e.g. dedifferentiated chondrosarcoma). Commensurate with the different clinical and oncological manifestations of the cartilage tumours, there are wide differences in the treatment and clinical course of the individual tumour. This article discusses the problems in the diagnosis and treatment of cartilage tumours from an orthopaedic point of view.