Arne Streitbürger

Incidence, predictive factors, and prognosis of chondrosarcoma in patients with Ollier disease and Maffucci syndrome: an international multicenter study of 161 patients.

BACKGROUND Enchondromatosis is characterized by the presence of multiple benign cartilage lesions in bone. While Ollier disease is typified by multiple enchondromas, in Maffucci syndrome these are associated with hemangiomas. Studies evaluating the predictive value of clinical symptoms for development of secondary chondrosarcoma and prognosis are lacking. This multi-institute study evaluates the clinical characteristics of patients, to get better insight on behavior and prognosis of these diseases. METHOD A retrospective study was conducted using clinical data of 144 Ollier and 17 Maffucci patients from 13 European centers and one national databank supplied by members of the European Musculoskeletal Oncology Society. RESULTS Patients had multiple enchondromas in the hands and feet only (group I, 18%), in long bones including scapula and pelvis only (group II, 39%), and in both small and long/flat bones (group III, 43%), respectively. The overall incidence of chondrosarcoma thus far is 40%. In group I, only 4 patients (15%) developed chondrosarcoma, in contrast to 27 patients (43%) in group II and 26 patients (46%) in group III, respectively. The risk of developing chondrosarcoma is increased when enchondromas are located in the pelvis (odds ratio, 3.8; p = 0.00l). CONCLUSIONS Overall incidence of development of chondrosarcoma is 40%, but may, due to age-dependency, increase when considered as a lifelong risk. Patients with enchondromas located in long bones or axial skeleton, especially the pelvis, have a seriously increased risk of developing chondrosarcoma, and are identified as the population that needs regular screening on early detection of malignant transformation.

The influence of elementary silver versus titanium on osteoblasts behaviour in vitro using human osteosarcoma cell lines.

Purpose. The antimicrobial effect of a silver-coated tumor endoprosthesis has been proven in clinical and experimental trials. However, in the literature there are no reports concerning the effect of elementary silver on osteoblast behaviour. Therefore, the prosthetic stem was not silver-coated because of concerns regarding a possible inhibition of the osseointegration. The aim of the present study was to investigate the effect of 5–25 mg of elementary silver in comparison to Ti-6Al-4V on human osteosarcoma cell lines (HOS-58, SAOS). Methods. Cell viability was determined by measuring the MTT proliferation rate. Cell function was studied by measuring alkaline phosphatase (AP) activity and osteocalcine production. Results. In the HOS-58 cells, the AP activity was statistically significant (P < 0.05) higher at a supplement of 5–10 mg of silver than of Ti-6 Al-4V at the same doses. For both cell lines, a supplement above 10 mg of silver resulted in a reduced AP activity in comparision to the Ti-6 Al-4V group, but a statistically significant difference (P < 0.05) was observed at a dose of 25 mg for the SAOS cells only. At doses of 20–25 mg in the HOS-58 cells and 10–25 mg in the SAOS cells, the reduction of the proliferation rate by silver was statistically significant (P < 0.05) compared to the Ti-6 Al-4V supplement. Discussion. In conclusion, elementary silver exhibits no cytotoxicity at low concentrations. In contrast, it seems to be superior to Ti-6 Al-4V concerning the stimulation of osteogenic maturation at these concentrations, whereas at higher doses it causes the known cytotoxic properties.

Endoprosthetic replacement after extra-articular resection of bone and soft-tissue tumours around the knee

We evaluated the clinical results and complications after extra-articular resection of the distal femur and/or proximal tibia and reconstruction with a tumour endoprosthesis (MUTARS) in 59 patients (mean age 33 years (11 to 74)) with malignant bone or soft-tissue tumours. According to a Kaplan-Meier analysis, limb survival was 76% (95% confidence interval (CI) 64.1 to 88.5) after a mean follow-up of 4.7 years (one month to 17 years). Peri-prosthetic infection was the most common indication for subsequent amputation (eight patients). Survival of the prosthesis without revision was 48% (95% CI 34.8 to 62.0) at two years and 25% (95% CI 11.1 to 39.9) at five years post-operatively. Failure of the prosthesis was due to deep infection in 22 patients (37%), aseptic loosening in ten patients (17%), and peri-prosthetic fracture in six patients (10%). Wear of the bearings made a minor revision necessary in 12 patients (20%). The mean Musculoskeletal Tumor Society score was 23 (10 to 29). An extensor lag > 10° was noted in ten patients (17%). These results suggest that limb salvage after extra-articular resection with a tumour prosthesis can achieve good functional results in most patients, although the rates of complications and subsequent amputation are higher than in patients treated with intra-articular resection.

Modular Endoprosthetic Reconstruction in Malignant Bone Tumors: Indications and Limits

Modular tumor prostheses are well established today for the reconstruction of osseous defects after resection of malignant bone tumors. Almost every joint and even total bones (e.g., total femur or humerus) can be replaced with promising functional results, dramatically reducing the need for ablative procedures. Although the complication rate with the use of modern modular endoprostheses is constantly decreasing, the need for revision surgery is still significantly higher than in primary joint arthroplasty. In this review we present the modular endoprosthesis system developed in our institution, summarize the postoperative management, and discuss the indications, limits, and complications as well as the functional results.

Reconstruction after wide resection of the entire distal fibula in malignant bone tumours

In this study we present a series of patients (n = 11) with resection of the entire distal fibula in the case of sarcoma or metastasis. Moreover, we describe a new method to restore ankle stability with a tibiotalocalcaneal arthrodesis using a retrograde hindfoot nail (n = 4) in contrast to tibiotalar arthrodesis with screws (n = 5). The screw fixation failed in two patients due to osteopoenic bone. The crucial benefits of an arthrodesis with a retrograde nail are a stable arthrodesis, intramedullary stabilisation of the tibia and avoidance of extrinsic material in the wound area. An arthrodesis with a retrograde nail is a good alternative for reconstruction after a wide distal fibula resection. The additional arthrodesis of the subtalar joint was not associated with worse functional results in the MSTS and TESS scores.

Surgical difficulties encountered with use of modular endoprosthesis for limb preserving salvage of failed allograft reconstruction after malignant tumor resection.

We reviewed outcomes and discussed surgical difficulties encountered in 10 patients who had modular endoprosthesis for limb preserving salvage of failed allograft reconstruction after malignant tumor resection. Mean allograft survival time before failure was 127.4 months (range, 14-264 months). Mean length of follow-up since endoprosthesis revision surgery was 62.8 months (range, 16-132 months). There was one endoprosthesis failure, resulting in a mean endoprosthesis survival time of 56.9 months (range, 16-132). Complications included arterial laceration, nerve injury, periprosthetic crack fracture, aseptic loosening, and infection. Modular endoprosthesis remain a viable option that should be considered in any limb preserving salvage of failed allograft reconstructions. However, altered anatomy, poor/short remnant host bone, periprosthetic fractures, inadequate soft tissue coverage and infection remain important difficulties encountered.

LUMiC(®) Endoprosthetic Reconstruction After Periacetabular Tumor Resection: Short-term Results.

BackgroundReconstruction of periacetabular defects after pelvic tumor resection ranks among the most challenging procedures in orthopaedic oncology, and reconstructive techniques are generally associated with dissatisfying mechanical and nonmechanical complication rates. In an attempt to reduce the risk of dislocation, aseptic loosening, and infection, we introduced the LUMiC® prosthesis (implantcast, Buxtehude, Germany) in 2008. The LUMiC® prosthesis is a modular device, built of a separate stem (hydroxyapatite-coated uncemented or cemented) and acetabular cup. The stem and cup are available in different sizes (the latter of which is also available with silver coating for infection prevention) and are equipped with sawteeth at the junction to allow for rotational adjustment of cup position after implantation of the stem. Whether this implant indeed is durable at short-term followup has not been evaluated.Questions/purposes(1) What proportion of patients experience mechanical complications and what are the associated risk factors of periacetabular reconstruction with the LUMiC® after pelvic tumor resection? (2) What proportion of patients experience nonmechanical complications and what are the associated risk factors of periacetabular reconstruction with the LUMiC® after pelvic tumor resection? (3) What is the cumulative incidence of implant failure at 2 and 5 years and what are the mechanisms of reconstruction failure? (4) What is the functional outcome as assessed by Musculoskeletal Tumor Society (MSTS) score at final followup?MethodsWe performed a retrospective chart review of every patient in whom a LUMiC® prosthesis was used to reconstruct a periacetabular defect after internal hemipelvectomy for a pelvic tumor from July 2008 to June 2014 in eight centers of orthopaedic oncology with a minimum followup of 24 months. Forty-seven patients (26 men [55%]) with a mean age of 50 years (range, 12–78 years) were included. At review, 32 patients (68%) were alive. The reverse Kaplan-Meier method was used to calculate median followup, which was equal to 3.9 years (95% confidence interval [CI], 3.4–4.3). During the period under study, our general indications for using this implant were reconstruction of periacetabular defects after pelvic tumor resections in which the medial ilium adjacent to the sacroiliac joint was preserved; alternative treatments included hip transposition and saddle or custom-made prostheses in some of the contributing centers; these were generally used when the medial ilium was involved in the tumorous process or if the LUMiC® was not yet available in the specific country at that time. Conventional chondrosarcoma was the predominant diagnosis (n = 22 [47%]); five patients (11%) had osseous metastases of a distant carcinoma and three (6%) had multiple myeloma. Uncemented fixation (n = 43 [91%]) was preferred. Dual-mobility cups (n = 24 [51%]) were mainly used in case of a higher presumed risk of dislocation in the early period of our study; later, dual-mobility cups became the standard for the majority of the reconstructions. Silver-coated acetabular cups were used in 29 reconstructions (62%); because only the largest cup size was available with silver coating, its use depended on the cup size that was chosen. We used a competing risk model to estimate the cumulative incidence of implant failure.ResultsSix patients (13%) had a single dislocation; four (9%) had recurrent dislocations. The risk of dislocation was lower in reconstructions with a dual-mobility cup (one of 24 [4%]) than in those without (nine of 23 [39%]) (hazard ratio, 0.11; 95% CI, 0.01–0.89; p = 0.038). Three patients (6%; one with a preceding structural allograft reconstruction, one with poor initial fixation as a result of an intraoperative fracture, and one with a cemented stem) had loosening and underwent revision. Infections occurred in 13 reconstructions (28%). Median duration of surgery was 6.5 hours (range, 4.0–13.6 hours) for patients with an infection and 5.3 hours (range, 2.8–9.9 hours) for those without (p = 0.060); blood loss was 2.3 L (range, 0.8–8.2 L) for patients with an infection and 1.5 L (range, 0.4–3.8 L) for those without (p = 0.039). The cumulative incidences of implant failure at 2 and 5 years were 2.1% (95% CI, 0–6.3) and 17.3% (95% CI, 0.7–33.9) for mechanical reasons and 6.4% (95% CI, 0–13.4) and 9.2% (95% CI, 0.5–17.9) for infection, respectively. Reasons for reconstruction failure were instability (n = 1 [2%]), loosening (n = 3 [6%]), and infection (n = 4 [9%]). Mean MSTS functional outcome score at followup was 70% (range, 33%–93%).ConclusionsAt short-term followup, the LUMiC® prosthesis demonstrated a low frequency of mechanical complications and failure when used to reconstruct the acetabulum in patients who underwent major pelvic tumor resections, and we believe this is a useful reconstruction for periacetabular resections for tumor or failed prior reconstructions. Still, infection and dislocation are relatively common after these complex reconstructions. Dual-mobility articulation in our experience is associated with a lower risk of dislocation. Future, larger studies will need to further control for factors such as dual-mobility articulation and silver coating. We will continue to follow our patients over the longer term to ascertain the role of this implant in this setting.Level of EvidenceLevel IV, therapeutic study.

Pelvic reconstruction with compound osteosynthesis following hemipelvectomy

To date, all surgical techniques used for reconstruction of the pelvic ring following supra-acetabular tumour resection produce high complication rates. We evaluated the clinical, oncological and functional outcomes of a cohort of 35 patients (15 men and 20 women), including 21 Ewings sarcomas, six chondrosarcomas, three sarcomas not otherwise specified, one osteosarcoma, two osseous malignant fibrous histiocytomas, one synovial cell sarcoma and one metastasis. The mean age of the patients was 31 years (8 to 79) and the latest follow-up was carried out at a mean of 46 months (1.9 to 139.5) post-operatively. We undertook a functional reconstruction of the pelvic ring using polyaxial screws and titanium rods. In 31 patients (89%) the construct was encased in antibiotic-impregnated polymethylmethacrylate. Preservation of the extremities was possible for all patients. The survival rate at three years was 93.9% (95% confidence interval (CI) 77.9 to 98.4), at five years it was 82.4% (95% CI 57.6 to 93.4). For the 21 patients with Ewings sarcoma it was 95.2% (95% CI 70.7 to 99.3) and 81.5% (95% CI 52.0 to 93.8), respectively. Wound healing problems were observed in eight patients, deep infection in five and clinically asymptomatic breakage of the screws in six. The five-year implant survival was 93.3% (95% CI 57.8 to 95.7). Patients were mobilised at a mean of 3.5 weeks (1 to 7) post-operatively. A post-operative neurological defect occurred in 12 patients. The mean Musculoskeletal Tumor Society score at last available follow-up was 21.2 (10 to 27). This reconstruction technique is characterised by simple and oncologically appropriate applicability, achieving high primary stability that allows early mobilisation, good functional results and relatively low complication rates.

[Bone defect reconstruction in bone sarcoma surgery: tumour endoprosthesis versus biological reconstruction].

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.ZusammenfassungHintergrundKnochensarkome kommen sowohl gehäuft im Kindes und Jugendalter aber auch in jedem Erwachsenenalter vor. Hauptlokalisation sind die langen Röhrenknochen der Extremitäten sowie das Beckenskelett. Meta-/diaphysär lokalisierte Tumoren, deren Entfernung einen Gelenkersatz notwendig macht, überwiegen gegenüber rein diaphsyär lokalisierten Tumoren.FragestellungLokalisationsabhängig kommen sowohl endoprothetische oder auch biologische Rekonstruktionsverfahren zu Anwendung. Alle Verfahren bieten verfahrensspezifische Vor- und Nachteile.ErgebnisseBei der Wahl des geeigneten Verfahrens müssen eine Vielzahl von Einflussfaktoren berücksichtigt werden. So sind grundlegende Erwägungen wie das Alter des Patienten (Weichteilsituation/Restwachstum/biologisches Potential), die Therapieintention im onkologischen Kontext (Palliation/Kuration), die Lokalisation (obere/untere Extremität) als auch die Tumorausdehnung im Knochen (Diaphyse/Metaphyse) oder auch die onkologische Gesamttherapie (Chemotherapie/lokale Strahlentherapie) zu berücksichtigen. Alle diese Faktoren beeinflussen die Wahl des Rekonstruktionsverfahrens ebenso wie das zu erwartende Gesamtergebnis.SchlussfolgerungDie Knochensarkomchirurgie bedarf einer breiten operativen Erfahrung des onkologischen Chirurgen. Nur durch Kenntnis der einzelnen Operationsverfahren kann das gesamte Spektrum der aktuellen Rekonstruktionsformen angeboten werden um das bestmögliche onkologische und funktionale Ergebnis für den individuellen Patienten zu erzielen.AbstractBackgroundPrimary 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.AimIn the treatment of these tumours, both endoprosthetic replacement and biological reconstruction techniques are used. Each technique has method-specific advantages and disadvantages.ResultsTo 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.ConclusionSurgical 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.

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.ZusammenfassungHintergrundKnochensarkome kommen sowohl gehäuft im Kindes und Jugendalter aber auch in jedem Erwachsenenalter vor. Hauptlokalisation sind die langen Röhrenknochen der Extremitäten sowie das Beckenskelett. Meta-/diaphysär lokalisierte Tumoren, deren Entfernung einen Gelenkersatz notwendig macht, überwiegen gegenüber rein diaphsyär lokalisierten Tumoren.FragestellungLokalisationsabhängig kommen sowohl endoprothetische oder auch biologische Rekonstruktionsverfahren zu Anwendung. Alle Verfahren bieten verfahrensspezifische Vor- und Nachteile.ErgebnisseBei der Wahl des geeigneten Verfahrens müssen eine Vielzahl von Einflussfaktoren berücksichtigt werden. So sind grundlegende Erwägungen wie das Alter des Patienten (Weichteilsituation/Restwachstum/biologisches Potential), die Therapieintention im onkologischen Kontext (Palliation/Kuration), die Lokalisation (obere/untere Extremität) als auch die Tumorausdehnung im Knochen (Diaphyse/Metaphyse) oder auch die onkologische Gesamttherapie (Chemotherapie/lokale Strahlentherapie) zu berücksichtigen. Alle diese Faktoren beeinflussen die Wahl des Rekonstruktionsverfahrens ebenso wie das zu erwartende Gesamtergebnis.SchlussfolgerungDie Knochensarkomchirurgie bedarf einer breiten operativen Erfahrung des onkologischen Chirurgen. Nur durch Kenntnis der einzelnen Operationsverfahren kann das gesamte Spektrum der aktuellen Rekonstruktionsformen angeboten werden um das bestmögliche onkologische und funktionale Ergebnis für den individuellen Patienten zu erzielen.AbstractBackgroundPrimary 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.AimIn the treatment of these tumours, both endoprosthetic replacement and biological reconstruction techniques are used. Each technique has method-specific advantages and disadvantages.ResultsTo 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.ConclusionSurgical 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.