Life Expectancy After Treatment of Metastatic Bone Disease: An International Trend Analysis

INTRODUCTION

The decision to treat metastatic bone disease (MBD) surgically depends in part on patient life expectancy. We are unaware of an international analysis of how life expectancy among these patients has changed over time. Therefore, we asked (1) how has the life expectancy for patients treated for MBD changed over time, and (2) which, if any, of the common primary cancer types are associated with longer survival after treatment of MBD?

METHODS

We reviewed data collected from 2000 to 2022 in an international MBD database, as well as data used for survival model validation. We included 3,353 adults who underwent surgery and/or radiation. No patients were excluded. Patients were grouped by treatment date into period 1 (2000 to 2009), period 2 (2010 to 2019), and period 3 (2020 to 2022). Cumulative survival was portrayed using Kaplan-Meier curves; log-rank tests were used to determine significance at P < 0.05. Subgroup analyses by primary cancer diagnosis were performed.

RESULTS

Median survival in period 2 was longer than in period 1 ( P < 0.001). Median survival (at which point 50% of patients survived) had not been reached for period 3. Median survival was longer in period 2 for all cancer types ( P < 0.001) except thyroid. Only lung cancer reached median survival in period 3, which was longer compared with periods 1 and 2 ( P < 0.001). Slow-growth, moderate-growth, and rapid-growth tumors all demonstrated longer median survival from period 1 to period 2; only rapid-growth tumors reached median survival for period 3, which was longer compared with periods 1 and 2 ( P < 0.001).

DISCUSSION

Median duration of survival after treatment of MBD has increased, which was a consistent finding in nearly all cancer types. Longer survival is likely attributable to improvements in both medical and surgical treatments. As life expectancy for patients with MBD increases, surgical methods should be selected with this in mind.

LEVEL OF EVIDENCE

VI.

Case report and review: Angiosarcoma with thrombocytopenia after total hip arthroplasty

Total hip arthroplasty (THA) is a common treatment for osteoarthritis and is also performed for other conditions, such as secondary arthritis due to developmental dysplasia of the hip. Various THA types may be complicated by osteolysis and an inflammatory pseudotumor due to an adverse reaction to metal debris. Rarely, THA has been associated with malignant tumors, but their causality remains unclear. In this case report, we describe a female patient with developmental dysplasia of the hip. She had undergone left metal-on-polyethylene THA, acetabular revision of the THA, and left total knee arthroplasty. In addition, she had a history of dyslipidemia and telangiectasia of the eyes, anemia, hiatal hernia, and pleuritis. A THA-associated mass (suspected to be a pseudotumor) had been detected during a previous hospital admission due to pleuritis. She was hospitalized due to swelling in her left lower limb, fatigue, and bruises. A clinical examination revealed anemia, thrombocytopenia, and growth of the suspected pseudotumor. Within 6 weeks, she presented with bleeding of the oral mucosa, hemoptysis, melena, severe thrombocytopenia that did not respond to treatment, elevated D-dimer and C-reactive protein levels, severe pain, increased osteolysis, and fractures around the THA. Infection or malignancy was suspected, but two trocar biopsies suggested an inflammatory pseudotumor. Since her anemia and thrombocytopenia were considered to have been caused by an inflammatory process within the suspected pseudotumor, her suspected pseudotumor and all THA components were surgically removed. However, she developed severe alveolar hemorrhaging and hypoxia and died 2 weeks after her surgery. Histopathological analysis of her surgical and autopsy samples revealed highly malignant angiosarcoma. Although individual cases of malignancies associated with THA have been reported, the literature lacks a clear association between THA and increased cancer risk. Most pseudotumors are non-malignant. The patient's case presented in this report exemplifies the challenges to the differential diagnosis of a THA-associated pseudotumor and rare angiosarcoma. Atypically rapid tumor growth, severe osteolysis, and deterioration in the general wellbeing suggest a malignant disease.

Preoperative coagulation biomarkers associate with survival and pulmonary embolism after surgical treatment of non-spinal skeletal metastases

BACKGROUND

Thrombotic complications are synergistic and associated with orthopedic procedures, trauma, and malignancy. Because cancer enhances coagulation activity and vice versa, we assessed preoperative biomarkers for survival and complications after treatment of pathologic fractures in non-spinal skeletal metastases.

PATIENTS/METHODS

Our study population comprised 113 actual or impending pathologic fractures in 100 patients admitted to two referral centers. Laboratory variables were collected retrospectively from patient records and analyzed related to incidence of pulmonary embolism (PE) and mortality (Kaplan-Meier and Cox regression analyses and biomarker quartiles).

RESULTS

Preoperative coagulation variables were high without exceptions. PE occurred in 12 patients at 36 post-operative days at incidence of 11% in the lower and 13% in the upper extremity fractures. Patients with fibrinogen exceeding 5 g/l (log-rank 0.022) developed PE earlier (5 to 15 days postoperatively) than others. Also, mean patient survival with normal fibrinogen range (2-4 g/l) was 34 months, whereas it halved upon elevated fibrinogen (log-rank p = 0.009). Survival in patients with FVIII levels under 326 IU/dl (Q3) was 22 months, but only 7 months if FVIII exceeded 326 IU/dl (log-rank p = 0.002). Combined elevated fibrinogen and FVIII predicted survival: for patients with levels below threshold limits was 22 months versus only 7 months when both variables exceeded the ranges (log-rank p < 0.001). Multivariate analysis to control confounders supported an independent role of fibrinogen and FVIII for survival.

CONCLUSIONS

Our study has established fibrinogen and FVIII as potential preoperative contributors of survival and complications after treatment of metastatic fractures. These results highlight the need for novel anticoagulation and thromboprophylaxis strategies among these patients.

Correction: Effect of the orientation and fluid flow on the accumulation of organotin compounds to Chemcatcher passive samplers

Correction for 'Effect of the orientation and fluid flow on the accumulation of organotin compounds to Chemcatcher passive samplers' by H. Ahkola et al., Environ. Sci.: Processes Impacts, 2015, 17, 813-824, https://doi.org/10.1039/C4EM00585F.

Development and external validation of nomograms to predict sarcoma-specific death and disease progression after surgical resection of localized high-grade conventional primary central chondrosarcoma and dedifferentiated chondrosarcoma

AIMS

Our aim was to develop and validate nomograms that would predict the cumulative incidence of sarcoma-specific death (CISSD) and disease progression (CIDP) in patients with localized high-grade primary central and dedifferentiated chondrosarcoma.

METHODS

The study population consisted of 391 patients from two international sarcoma centres (development cohort) who had undergone definitive surgery for a localized high-grade (histological grade II or III) conventional primary central chondrosarcoma or dedifferentiated chondrosarcoma. Disease progression captured the first event of either metastasis or local recurrence. An independent cohort of 221 patients from three additional hospitals was used for external validation. Two nomograms were internally and externally validated for discrimination (c-index) and calibration plot.

RESULTS

In the development cohort, the CISSD at ten years was 32.9% (95% confidence interval (CI) 19.8% to 38.4%). Age at diagnosis, grade, and surgical margin were found to have significant effects on CISSD and CIDP in multivariate analyses. Maximum tumour diameter was also significantly associated with CISSD. In the development cohort, the c-indices for CISSD and CIDP at five years were 0.743 (95% CI 0.700 to 0.819) and 0.761 (95% CI 0.713 to 0.800), respectively. When applied to the validation cohort, the c-indices for CISSD and CIDP at five years were 0.839 (95% CI 0.763 to 0.916) and 0.749 (95% CI 0.672 to 0.825), respectively. The calibration plots for these two nomograms demonstrated good fit.

CONCLUSION

Our nomograms performed well on internal and external validation and can be used to predict CISSD and CIDP after resection of localized high-grade conventional primary central and dedifferentiated chondrosarcomas. They provide a new tool with which clinicians can assess and advise individual patients about their prognosis. Cite this article: Bone Joint J 2020;102-B(12):1752-1759.

Navigation-assisted pelvic resections and reconstructions for periacetabular chondrosarcomas

OBJECTIVES

Survival in patients with chondrosarcomas has not improved over 40 years. Although emerging evidence has documented the efficacy of navigation-assisted surgery, the prognostic significance in chondrosarcomas remains unknown. We aimed to assess the clinical benefit of navigation-assisted surgery for pelvic chondrosarcomas involving the peri-acetabulum.

METHODS

We studied 50 patients who underwent limb-sparing surgery for periacetabular chondrosarcomas performed with navigation (n = 13) without it (n = 37) at a referral musculoskeletal oncology centre between 2000 and 2015.

RESULTS

The intralesional resection rates in the navigated and non-navigated groups were 8% (n = 1) and 19% (n = 7), respectively; all bone resection margins were clear in the navigated group. The 5-year cumulative incidence of local recurrence was 23% and 56% in the navigated and non-navigated groups, respectively (p = 0.035). There were no intra-operative complications related to use of navigation. There was a trend toward better functional outcomes in the navigated group (mean MSTS score, 67%) than the non-navigated group (mean MSTS score, 60%; p = 0.412). At a mean follow-up of 63 months, the 5-year disease-specific survival was 76% and 53% in the navigated and non-navigated group, respectively (p = 0.085), whilst the 5-year progression-free survival was 62% and 28% in the navigated and non-navigated group, respectively (p = 0.032).

CONCLUSION

This study confirmed improved local control and progression-free survival with the use of computer navigation in patients with limb-salvage surgery for periacetabular chondrosarcomas, although the advancement in other treatment modalities is required for improvement of disease-specific survival.

Angiosarcoma of bone: A European Muscoloskeletal Oncology Society (EMSOS) multicenter, retrospective study

11046

Background: Angiosarcoma of bone (B-AS) is an exceedingly rare malignant tumor of vascular origin. The aim of this EMSOS retrospective study is to report on natural history, type of treatment and prognosis of B-AS. Methods: Patient data were collected according to the national rules for observational studies through electronic dataset available on EMSOS WEBsite. Results: 80 patients (51 male and 29 female, median age 54 years, range 17 to 92 years, 56% with localized disease, 44% metastatic) from 8 EMSOS Centers were collected. Surgery of the primary tumor was performed in 76% of patients (amputation in 30%), with intralesional margins in 26%. A surgical complete remission status (SCR) was achieved in 47% of the patients. Radiotherapy (RT) was delivered in 41% of the patients (in 15 patients as definitive local treatment), chemotherapy (CT) in 47% (56% in metastatic and 41% in localized cases). With a median follow-up of 31 months (range 40 to 309 months), 68% of patients died, 16% were disease-free, 12% were alive with disease and 4% dead for other causes. The 5-year overall survival (OS) was 27% (95%CI 16-30): 41% (95%CI 25-56) for localized patients (45% SCR, 17% no SCR, p = 0.03) and 8% (95%CI 0-20) for metastatic patients (p = 0.002). Among metastatic patients, 29/35 have died, with a median time to death of 6 months (1-45), while 6 patients were alive with a median follow-up of 22 months (8-106). Improved survival was observed for male patients (30% vs 8%, p = 0.04), while type of treatment (surgery, chemotherapy, radiation), pattern of metastases and age did not affect outcome. In 18 metastatic patients who underwent chemotherapy partial respo nse (PR) was documented in 1/3 patients after paclitaxel (RR 33%), and stable disease (SD) in 5 patients (2/2 with gemcitabine, 2/8 with doxorubicin/ifosfamide, and 1/4 with osteosarcoma-like chemotherapy). In localized patients, the 5-year OS was significantly better for age ≤ 50 years (68% vs 34%, p = 0.02) and extremity and central tumor as compared with pelvis/sacral location (50% vs 58% vs 0%, p = 0.008), with improved disease-free survival (DFS) after chemotherapy (49% vs 33%, p = 0.04). Conclusions: Metastatic B-AS is a fatal disease and inclusion in experimental trials is warranted. In localized patients, a better probability of survival is expected in younger and surgically treated patients. The use of chemotherapy was associated with improved DFS.

Comparison of volar-flexion, ulnar-deviation and functional position cast immobilization in the non-operative treatment of distal radius fracture in elderly patients: a pragmatic randomized controlled trial study protocol

Background

Distal radius fractures (DRFs) are the second most common fractures, after hip fractures, seen in clinical practice. The high incidence of low-energy trauma DRFs in elderly patients raises questions about the best treatment method in terms of function, pain, and quality of life. Although the majority of these fractures are treated non-operatively with cast immobilization, valid scientific evidence of the optimal cast immobilization is lacking. In addition, several publications, including Cochrane review have outlined the need for more evidence to determine the most appropriate method of cast immobilization.

Methods

This study is a pragmatic, prospective, randomized, multi-centre trial. The trial is designed to compare two widely used cast positions (volar flexion-ulnar deviation position and functional position) for the non-operative treatment of DRF in patients over 64 years of age. The main hypothesis of the trial is that function position yields corresponding functional outcome, pain relief and quality of life when compared to the volar flexion-ulnar deviation position. The primary outcome measure is Patient Rated Wrist Evaluation (PRWE) score and the secondary outcome measures will be the Disabilities of the Arm, Shoulder and Hand (DASH) score, Visual Analogue Scale (VAS), 15-dimensional (15D) value and rate of surgical interventions. The results of the trial will be analysed after 1 and 2-years.

Discussion

This publication presents a prospective, pragmatic, randomized, national multi-centre trial study protocol. It provides details of patient flow, randomization, follow-up and methods of analysis of the material as well as publication plan.

Trial registration

ClinicalTrials.gov identifier: NCT02894983 22 August 2016.

Electronic supplementary material

The online version of this article (10.1186/s12891-017-1759-y) contains supplementary material, which is available to authorized users.

The Scandinavian Sarcoma Group Central Register: 6,000 patients after 25 years of monitoring of referral and treatment of extremity and trunk wall soft-tissue sarcoma

Purpose - We wanted to examine the potential of the Scandinavian Sarcoma Group (SSG) Central Register, and evaluate referral and treatment practice for soft-tissue sarcomas in the extremities and trunk wall (STS) in the Nordic countries. Background - Based on incidence rates from the literature, 8,150 (7,000-9,300) cases of STS of the extremity and trunk wall should have been diagnosed in Norway, Finland, Iceland, and Sweden from 1987 through 2011. The SSG Register has 6,027 cases registered from this period, with 5,837 having complete registration of key variables. 10 centers have been reporting to the Register. The 5 centers that consistently report treat approximately 90% of the cases in their respective regions. The remaining centers have reported all the patients who were treated during certain time periods, but not for the entire 25-year period. Results - 59% of patients were referred to a sarcoma center untouched, i.e. before any attempt at open biopsy. There was an improvement from 52% during the first 5 years to 70% during the last 5 years. 50% had wide or better margins at surgery. Wide margins are now achieved less often than 20 years ago, in parallel with an increase in the use of radiotherapy. For the centers that consistently report, 97% of surviving patients are followed for more than 4 years. Metastasis-free survival (MFS) increased from 67% to 73% during the 25-year period. Interpretation - The Register is considered to be representative of extremity and trunk wall sarcoma disease in the population of Scandinavia, treated at the reporting centers. There were no clinically significant differences in treatment results at these centers.

High blood metal ion levels in 19 of 22 patients with metal-on-metal hinge knee replacements

Background and purpose - There has been increasing alarm regarding metal-on-metal (MoM) joint replacements leading to elevated levels of metal ions and adverse reactions to metal debris (ARMDs). There is little information available concerning the prevalence of and risk factors for these adverse reactions, except with MoM hip joint replacements. We determined the levels of metal ions in blood and the rate of revision due to ARMDs in patients treated with MoM hinge total knee arthroplasty (TKA). Patients and methods - 22 patients with TKAs and MoM hinge connecting mechanisms were studied for whole-blood chromium and cobalt levels at 6 months, 1 year, and/or ≥2 years after surgery. Possible ARMDs were investigated by MRI. 12 patients with TKAs and metal-on-polyethylene (MoP) connecting mechanisms served as controls. Results - The cobalt levels were over 5 ppb in 19 of the 22 patients in the MoM group and in 1 of the 12 patients in the MoP group. The chromium levels were over 5 ppb in 11 of the 22 patients in the MoM group and in none of the 12 patients in the MoP group. Pseudotumors were operated in 4 of the 22 patients in the MoM group and in none of the patients in the MoP group. Interpretation - Our results clearly show that the MoM hinge TKA carries a high risk of increased levels of systemic metal ions and also local ARMD, leading to complicated knee revisions. We therefore discourage the use of MoM hinge TKA.

Individualised risk assessment for local recurrence and distant metastases in a retrospective transatlantic cohort of 687 patients with high-grade soft tissue sarcomas of the extremities: a multistate model

OBJECTIVES

This study investigates the effect of surgical margins and radiotherapy, in the presence of individual baseline characteristics, on survival in a large population of high-grade soft tissue sarcoma of the extremities using a multistate model.

DESIGN

A retrospective multicentre cohort study.

SETTING

4 tertiary referral centres for orthopaedic oncology.

PARTICIPANTS

687 patients with primary, non-disseminated, high-grade sarcoma only, receiving surgical treatment with curative intent between 2000 and 2010 were included.

MAIN OUTCOME MEASURES

The risk to progress from 'alive without disease' (ANED) after surgery to 'local recurrence' (LR) or 'distant metastasis (DM)/death'. The effect of surgical margins and (neo)adjuvant radiotherapy on LR and overall survival was evaluated taking patients' and tumour characteristics into account.

RESULTS

The multistate model underlined that wide surgical margins and the use of neoadjuvant radiotherapy decreased the risk of LR but have little effect on survival. The main prognostic risk factors for transition ANED to LR are tumour size (HR 1.06; 95% CI 1.01 to 1.11 (size in cm)) and (neo)adjuvant radiotherapy. The HRs for patients treated with adjuvant or no radiotherapy compared with neoadjuvant radiotherapy are equal to 4.36 (95% CI 1.34 to 14.24) and 14.20 (95% CI 4.14 to 48.75), respectively. Surgical resection margins had a protective effect for the occurrence of LR with HRs equal to 0.61 (95% CI 0.33 to 1.12), and 0.16 (95% CI 0.07 to 0.41) for margins between 0 and 2 mm and wider than 2 mm, respectively. For transition ANED to distant metastases/Death, age (HR 1.64 (95% CI 0.95 to 2.85) and 1.90 (95% CI 1.09 to 3.29) for 25-50 years and >50 years, respectively) and tumour size (1.06 (95% CI 1.04 to 1.08)) were prognostic factors.

CONCLUSIONS

This paper underlined the alternating effect of surgical margins and the use of neoadjuvant radiotherapy on oncological outcomes between patients with different baseline characteristics. The multistate model incorporates this essential information of a specific patient's history, tumour characteristics and adjuvant treatment modalities and allows a more comprehensive prediction of future events.

Ewing’s sarcoma

Aims

The purpose of this study was to review a large cohort of patients and further assess the correlation between the histological response to chemotherapy in patients with Ewing’s sarcoma with the overall (OS) and event-free survival (EFS).

Patients and Methods

All patients treated for Ewing’s sarcoma between 1980 and 2012 were reviewed. Of these, 293 patients without metastases at the time of diagnosis and treated with chemotherapy and surgery were included. Patients were grouped according to the percentage of necrosis after chemotherapy: Group I: 0% to 50%, Group II: 51% to 99% and Group III: 100%.

Results

The mean age at diagnosis was 16 years (1 to 62) and the mean follow-up was 9.1 years (six months to 32.6 years). The OS and EFS for the series were 75% and 65% at five years. There were significant differences in survival between the groups of necrosis: 0% to 50% (OS: 49% and EFS: 45% at five years, respectively) compared with 51% to 99% (OS: 72% and EFS: 59% at five years, respectively) and 100% (OS: 94% and EFS: 81% at five years, respectively) (p <  0.001). There were no significant differences in survival between patients treated between 1980 and 1989 compared with those treated between 1990 and 1999, and those treated between 2000 and 2012 (p = 0.55).

Conclusion

Only patients with 100% necrosis after chemotherapy should be classified as having a good response to chemotherapy because they have significantly better rates of survival compared with those with any viable tumour in the surgical specimen. Cite this article: Bone Joint J 2016;98-B:1138–44.

Osteosarcoma of the pelvis

Aims

Osteosarcoma of the pelvis is a particularly difficult tumour to treat as it often presents late, may be of considerable size and/or associated with metastases when it presents, and is frequently chondroid in origin and resistant to chemotherapy. The aim of this study was to review our experience of managing this group of patients and to identify features predictive of a poor outcome.

Patients and Methods

Between 1983 and 2014, 121 patients, (74 females and 47 males) were treated at a single hospital: 74 (61.2%) patients had a primary osteosarcoma and 47 (38.8%) had an osteosarcoma which was secondary either to Paget’s disease (22; 18.2%) or to previous pelvic irradiation (25; 20.7%). The mean age of those with a primary osteosarcoma was 29.3 years (nine to 76) and their mean follow-up 2.9 years (0 to 29). The mean age of those with a secondary sarcoma was 61.9 years (15 to 85) and their mean follow-up was one year (0 to 14). A total of 22 patients with a primary sarcoma (52.4%) and 20 of those with a secondary sarcoma (47.6%) had metastases at the time of presentation.

Results

The disease-specific survival at five years for all patients was 27.2%. For those without metastases at the time of diagnosis, the five-year survival was 32.7%. Factors associated with a poor outcome were metastases at diagnosis and secondary tumours. In primary osteosarcoma, sacral location, surgical margin and a diameter > 10 cm were associated with a poor outcome.

Conclusion

In this, the largest single series of patients with an osteosarcoma of the pelvis treated in a single hospital, those with secondary tumours and those with metastases at presentation had a particularly poor outcome. For those with a primary sarcoma, sacral location, an intralesional margin and a diameter of > 10 cm were poor prognostic indicators. Cite this article: Bone Joint J 2016;98-B:555–63.

Surgery of non-spinal skeletal metastases in renal cell carcinoma: No effect of preoperative embolization?

BACKGROUND AND PURPOSE

Surgery for metastases of renal cell carcinoma has increased in the last decade. It carries a risk of massive blood loss, as tumors are hypervascular and the surgery is often extensive. Preoperative embolization is believed to facilitate surgery. We evaluated the effect of preoperative embolization and resection margin on intraoperative blood loss, operation time, and survival in non-spinal skeletal metastases of renal cell carcinoma.

PATIENTS AND METHODS

This retrospective study involved 144 patients, 56 of which were treated preoperatively with embolization. The primary outcome was intraoperative blood loss. We also identified factors affecting operating time and survival.

RESULTS

We did not find statistically significant effects on intraoperative blood loss of preoperative embolization of skeletal non-spinal metastases. Pelvic localization and large tumor size increased intraoperative blood loss. Marginal resection compared to intralesional resection, nephrectomy, level of hemoglobin, and solitary metastases were associated with better survival.

INTERPRETATION

Tumor size, but not embolization, was an independent factor for intraoperative blood loss. Marginal resection rather than intralesional resection should be the gold standard treatment for skeletal metastases in non-spinal renal cell carcinoma, especially in the case of a solitary lesion, as this improved the overall survival.

Venous thromboembolism after surgical treatment of non-spinal skeletal metastases - An underdiagnosed complication

INTRODUCTION AND AIM

Venous thromboembolism (VTE) is a severe complication associated both with major orthopaedic surgery and cancer. However, survival and postoperative complications of skeletal metastases despite their thrombogenic potential, have received little attention in both the clinical management and research setting. This single-centre observational cohort study aimed to evaluate the incidence and impact of VTE in association with cancer surgery targeted to the management of fractures secondary to skeletal metastases.

METHODS

Data were collected retrospectively from the medical database. We included consecutive 306 patients operated for 343 non-spinal skeletal metastases during a 15-year period (1999-2014). The incidence of VTE and its risk factors were assessed using binary logistic regression analysis. Kaplan-Meier and Cox regression analyses were used to evaluate variables affecting survival.

RESULTS

The rate of symptomatic VTE was 10% (30/306) during the 3-month postoperative period, while 79% received thromboprophylaxis. Fatal pulmonary embolism (PE) rate was high, 3.3% (10/306) after surgery. Intraoperative oxygen saturation drop, pulmonary metastases and intramedullary nailing were independent risk factors for VTE. Indicators of decreased survival were lung cancer, intramedullary nailing, multiple skeletal and pulmonary metastases, anaemia, leukocytosis, and PE.

CONCLUSION

Relationship between fractures secondary to skeletal metastases and VTE needs further clinical attention. Whether the survival of patients with fractures secondary to skeletal metastases can be improved by targeted thromboprophylactic means should be studied further.

Do Treatment Policies for Proximal Humerus Fractures Differ among Three Nordic Countries and Estonia? Results of a Survey Study

BACKGROUND AND PURPOSE

Proximal humerus fractures are common fragility injuries. The incidence of these fractures has been estimated to be 82-105 per 105 person-years. Treatment of this fracture, especially in the elderly, is controversial. Our study group published a systematic review of the available literature and concluded that non-operative methods are favored over operative methods in three- and four-part fractures. The aim of this multinational study was to compare treatment policies for proximal humerus fractures among the Nordic countries and Estonia.

MATERIALS AND METHODS

The study was conducted as a questionnaire-based survey, using the Internet-based program, Webropol(®) (webropol.com). The questionnaire link was sent to the surgeons responsible for treating proximal humerus fractures in major public hospitals in Estonia, Finland, Norway, and Sweden. Questionnaire included questions regarding the responder's hospital, patient characteristics, and examinations taken before decision making. Clinical part included eight example patient cases with treatment options.

RESULTS

Of the 77 recipients of the questionnaire, 59 responded; consequently, the response rate was 77%. Based on the eight presented displaced fracture examples, in both Estonia and Norway and in Finland, 41% and 38%, respectively, preferred surgical treatment with locking plate. In Sweden, the percentage was 28%. The pre- and post-operative protocols showed a similarity in all participant countries.

CONCLUSION

Our survey revealed a remarkable uniformity in the current practice of operative treatments and rehabilitation for proximal humerus fractures in the participant countries.

The prognostic and therapeutic factors which influence the oncological outcome of parosteal osteosarcoma

The aim of this study was to evaluate the prognostic and therapeutic factors which influence the oncological outcome of parosteal osteosarcoma.

A total of 80 patients with a primary parosteal osteosarcoma were included in this retrospective study. There were 51 females and 29 males with a mean age of 29.9 years (11 to 78).

The mean follow-up was 11.2 years (1 to 40). Overall survival was 91.8% at five years and 87.8% at ten years. Local recurrence occurred in 14 (17.5%) patients and was associated with intralesional surgery and a large volume of tumour. On histological examination, 80% of the local recurrences were dedifferentiated high-grade tumours. A total of 12 (14.8%) patients developed pulmonary metastases, of whom half had either a dedifferentiated tumour or a local recurrence. Female gender and young age were good prognostic factors. Local recurrence was a poor prognostic factor for survival. Medullary involvement or the use of chemotherapy had no impact on survival.

The main goal in treating a parosteal osteosarcoma must be to achieve a wide surgical margin, as inadequate margins are associated with local recurrence. Local recurrence has a significant negative effect on survival, as 80% of the local recurrences are high-grade dedifferentiated tumours, and half of these patients develop metastases.

The role of chemotherapy in the treatment of parosteal osteosarcoma is not as obvious as it is in the treatment of conventional osteosarcoma. The mainstay of treatment is wide local excision.

Cite this article: Bone Joint J 2015;97-B:1698–1703.

Genetic alterations in periprosthetic soft-tissue masses from patients with metal-on-metal hip replacement

Adverse soft tissue reactions in patients with metal-on-metal (MoM) hip replacement are associated with cobalt (Co) and chromium (Cr) particles released from the implant. Exposing the patients to long periods of increased metal ions concentrations resulting from the wear of these implants poses an increased risk of genotoxicity/mutagenicity. A variable proportion of patients develop periprosthetic soft-tissue masses or pseudotumors at the site of the implant. There is a concern that exposure to increased metal ions could increase the risk of cancer. In order to investigate whether the periprosthetic soft-tissue mass harbours any cancer- related genetic alterations, we studied DNA isolated from periprosthetic tissues of 20 patients with MoM hip replacement, for copy number alterations and mutations in hotspot regions of 50 cancer genes using aCGH and amplicon-based next generation sequencing. Our results showed copy number gains at 12q14.3 and 21q21.1in tumour from patient diagnosed with liposarcoma. Copy number alterations in periprosthetic tissues were seen in three other patients, one had a region of gain at 9q24.1 affecting JAK2 and INSL6, and two patients had region of gain at 6p21.1, affecting RUNX2. Mutation analysis showed V1578del mutation in NOTCH1 in two patients. The copy number alterations and mutations seen in periprosthetic soft-tissue masses are earlier reported in either haematological malignancies or in osteoblast related bone dysplasia. The presence of genetic anomalies was associated with longer in-situ time of the implant. Our findings warrant the need of similar studies in larger patient cohorts to evaluate the risk of development of neoplastic alterations in periprosthetic tissues of patients with MoM hip replacement.

Primary flap reconstruction of tissue defects after sarcoma surgery enables curative treatment with acceptable functional results: a 7-year review

Background

Sarcomas, a heterogeneous group of tumors, are challenging to treat and require multidisciplinary cooperation and planning. We analyzed the efficacy of flap reconstruction in patients with bone and soft tissue sarcoma.

Methods

Patient charts and operative records were retrospectively reviewed from January 2006 through October 2013 to identify sarcoma patient characteristics, postoperative complications, revisions, recurrences, and survival. Pedicled and/or free flap reconstruction was performed in 109 patients. Flap selection was based on defect size, and exposure of anatomically critical structures or major orthopedic implants.

Results

Of 109 patients, 71 (65.1 %) were men, and mean age was 56.4 years. Tumors most frequently located in a lower extremity (38.7 %). Primary sarcomas comprised 79.2 % and recurrences occurred in 18.9 %. Wide resection was performed for 65.7 %, and there were 10 planned amputations combined with flap reconstruction. A total of 111 tumors received 128 flaps: 76 pedicled flaps, 42 free flaps, and 5 combined (10 total) pedicled + free-flaps. The success rate was 94 % for the pedicled flap group, 97 % for the free-flap group, and 100 % for the pedicle + free-flap group. Of 35 patients, 5 developed deep prosthetic infections. Only one amputation due to disease progression was performed. Satisfactory functional outcome was achieved in 69 %. Survival rate during a mean (standard deviation) 3(2) year follow-up was 83.5 %.

Conclusions

Primary flap reconstruction after sarcoma surgery satisfies oncologic goals. Large tumors in difficult areas can be removed and complete tumor resection achieved. Our findings indicate a high survival rate after sarcoma surgery utilizing flap reconstruction and a low recurrence rate.

Treatment of proximal humerus fractures in the elderly: a systemic review of 409 patients

BACKGROUND AND PURPOSE

There is no consensus on the treatment of proximal humerus fractures in the elderly.

PATIENTS AND METHODS

We conducted a systematic search of the medical literature for randomized controlled trials and controlled clinical trials from 1946 to Apr 30, 2014. Predefined PICOS criteria were used to search relevant publications. We included randomized controlled trials involving 2- to 4-part proximal humerus fractures in patients over 60 years of age that compared operative treatment to any operative or nonoperative treatment, with a minimum of 20 patients in each group and a minimum follow-up of 1 year. Outcomes had to be assessed with functional or disability measures, or a quality-of-life score.

RESULTS

After 2 independent researchers had read 777 abstracts, 9 publications with 409 patients were accepted for the final analysis. No statistically significant differences were found between nonoperative treatment and operative treatment with a locking plate for any disability, for quality-of-life score, or for pain, in patients with 3- or 4-part fractures. In 4-part fractures, 2 trials found similar shoulder function between hemiarthroplasty and nonoperative treatment. 1 trial found slightly better health-related quality of life (higher EQ-5D scores) at 2-year follow-up after hemiarthroplasty. Complications were common in the operative treatment groups (10-29%).

INTERPRETATION

Nonoperative treatment over locking plate systems and tension banding is weakly supported. 2 trials provided weak to moderate evidence that for 4-part fractures, shoulder function is not better with hemiarthroplasty than with nonoperative treatment. 1 of the trials provided limited evidence that health-related quality of life may be better at 2-year follow-up after hemiarthroplasty. There is a high risk of complications after operative treatment.

Effect of the orientation and fluid flow on the accumulation of organotin compounds to Chemcatcher passive samplers

Monitoring of harmful substances in an aquatic environment is based on spot sampling which is the only sampling technique accepted by environmental authorities in the European Union. Still the implementation of the European Union Water Framework Directive (WFD) requires novel sampling tools for monitoring priority pollutants since their concentrations in natural waters can often remain below the limit of detection when using the conventional spot sampling method. However, this does not necessarily mean that the pollutant is not present in the aquatic environment. Many chemicals that are considered to be harmful are bioaccumulative and can affect, e.g., reproduction of aquatic organisms even at very low concentration levels. Also the timing is crucial since with spot sampling the pulse of harmful substances can easily be missed. Passive samplers collect the compounds for a certain amount of time which allows the concentrations in the sampler to rise to the measurable level where they are easy to detect. Organotin compounds (OTCs) have been widely used as plastic stabilizers and antifouling agents in ship paints and in many industrial processes. Among the OTCs, tributyltin is listed as a WFD priority substance. In this study a small-scale flow simulation around the Chemcatcher passive sampler was performed to visualize the flow streamlines in the vicinity of the sampler and to study the pressure experienced by the receiving phase in different sampler positions. With laboratory experiments the sampling rates for each OTC were determined and the effect of the flow velocity and sampler orientation on the accumulation of OTCs is discussed. The pressure changes were observed on the surface of the receiving phase in simulations with varying sampler orientations. Despite that, the laboratory experiments discovered no difference in the accumulation of compounds when varying the sampler orientation. The concentrations of OTCs in the surrounding water calculated from the passive sampling results were equivalent to the spot sampling ones. Hence, the Chemcatcher passive sampler provides a practical tool for the implementation of WFD.

Epidemiology of proximal humerus fractures

There are only a few previous population-based studies that include both inpatient and outpatient treatment data. The aim of this study was to investigate the epidemiology of proximal humerus fractures. The incidence of proximal humerus fractures increases with age, and we observe a seasonal variation strongly favoring winter months.

PURPOSE

Proximal humerus fractures are the third most common osteoporotic fracture type observed in elderly patients, after wrist and hip fractures. However, few previous population-based studies include both inpatient and outpatient treatment data. The aim of this study was to investigate the incidence, fracture morphology, and treatment method provided in cases of proximal humerus fractures.

METHODS

We retrospectively studied patient records from a mid-sized town in Finland between the years 2006 and 2010. The following data were collected from the medical records: age, sex, date of the fracture, laterality of the fracture, mechanism of injury, treatment method, and other associated fractures at the time of the original injury. Sex and age distributions of the patient population at risk (>18 years old) were calculated for the study period.

RESULTS

A total of 678 patients (females n = 503, 73 %) with 692 proximal humerus fractures were identified. The unadjusted incidence was 82 (95 % CI 76 to 88) per 100,000 person-years, 114 (95 % CI 104 to 124), and 47 (95 % CI 41 to 54) per 100,000 person-years in females and males, respectively. Incidence increased toward the older age groups. Clear seasonal variation was observed, two-part fractures were most common (428, 62 %), the majority of the fractures (n = 539, 78 %) were treated nonoperatively with a sling.

CONCLUSION

The incidence of proximal humerus fractures increases with age, and we observe a seasonal variation strongly favoring winter months. It is evident that proximal humerus fractures cause considerable morbidity among elderly people and consume health care resources.

Prognostic role of en-bloc resection and late onset of bone metastasis in patients with bone-seeking carcinomas of the kidney, breast, lung, and prostate: SSG study on 672 operated skeletal metastases

BACKGROUND AND OBJECTIVES

In metastatic disease, decisions regarding potential surgery require reliable data about the patient's survival. In this study, we evaluated different prognostic factors and their impact in four common primary tumors causing bone metastases.

METHODS

Data were acquired from the Scandinavian Sarcoma Group (SSG) metastasis registry. The patients underwent surgery between July 1999 and July 2009. This study included breast, prostate, lung, and kidney cancer cases, with a total of 672 operated non-spinal metastases. Differences in prognostic factors were evaluated using the Kaplan-Meier method with long-rank test. Cox regression multivariate analysis was performed to identify statistically independent prognostic factors.

RESULTS

Significant factors affecting survival were the presence of organ metastases, overall heath status, and disease load. In kidney cancer, en bloc resection of solitary metastases was associated with a significant fourfold longer survival compared to intralesional surgery. Preoperative radiotherapy was associated with higher complication and reoperation rates.

CONCLUSIONS

This data summary is important tool for clinicians to evaluate survival and choose treatment options for patients suffering from metastatic bone disease.

Orthopaedic reconstruction of complex pelvic bone defects. Evaluation of various treatment methods

Despite major developments in the field of revision surgery in recent decades, the management of severe acetabular deficiency at revision arthroplasty, complex primary total hip replacement or after pelvic tumour resection remains a complex problem. The options available for the management of severe bone loss include the use of uncemented press-fit cups with or without metal augments, impaction allografts, allograft-prosthesis composites, custom-made triflange cups, hip transposition, reconstruction prostheses or various combinations of these. This paper describes defect classification, various treatment options, clinical outcomes, survival of reconstruction, and typical complications in relation to treatment.

Insight opinion to surgically treated metastatic bone disease: Scandinavian Sarcoma Group Skeletal Metastasis Registry report of 1195 operated skeletal metastasis

The number of cancer patients living with metastatic disease is growing. The increased survival has led to an increase in the number of cancer-induced complications, such as pathologic fractures due to bone metastases. Surgery is most commonly needed for mechanical complications, such as fractures and intractable pain. We determined survival, disease free interval and complications in surgically treated bone metastasis. Data were collected from the Scandinavian Skeletal Metastasis Registry for patients with extremity skeletal metastases surgically treated at eight major Scandinavian referral centres between 1999 and 2009 covering a total of 1195 skeletal metastases in 1107 patients. Primary breast, prostate, renal, lung, and myeloma tumors make up 78% of the tumors. Number of complications is tolerable and is affected by methods of surgery as well as preoperative radiation therapy. Overall 1-year patient survival was 36%; however, mean survival was influenced by the primary tumor type and the presence of additional visceral metastases. Patients with impending fracture had more systemic complications than those with complete fracture. Although surgery is usually only a palliative treatment, patients can survive for years after surgery. We developed a simple, useful and reliable scoring system to predict survival among these patients. This scoring system gives good aid in predicting the prognosis when selecting the surgical method. While it is important to avoid unnecessary operations, operating when necessary can provide benefit.

External validation of the Bayesian Estimated Tools for Survival (BETS) models in patients with surgically treated skeletal metastases

Background

We recently developed two Bayesian networks, referred to as the Bayesian-Estimated Tools for Survival (BETS) models, capable of estimating the likelihood of survival at 3 and 12 months following surgery for patients with operable skeletal metastases (BETS-3 and BETS-12, respectively). In this study, we attempted to externally validate the BETS-3 and BETS-12 models using an independent, international dataset.

Methods

Data were collected from the Scandinavian Skeletal Metastasis Registry for patients with extremity skeletal metastases surgically treated at eight major Scandinavian referral centers between 1999 and 2009. These data were applied to the BETS-3 and BETS-12 models, which generated a probability of survival at 3 and 12 months for each patient. Model robustness was assessed using the area under the receiver-operating characteristic curve (AUC). An analysis of incorrect estimations was also performed.

Results

Our dataset contained 815 records with adequate follow-up information to establish survival at 12 months. All records were missing data including the surgeon’s estimate of survival, which was previously shown to be a first-degree associate of survival in both models. The AUCs for the BETS-3 and BETS-12 models were 0.79 and 0.76, respectively. Incorrect estimations by both models were more commonly optimistic than pessimistic.

Conclusions

The BETS-3 and BETS-12 models were successfully validated using an independent dataset containing missing data. These models are the first validated tools for accurately estimating postoperative survival in patients with operable skeletal metastases of the extremities and can provide the surgeon with valuable information to support clinical decisions in this patient population.

Production of pure samples of 131mXe and 135Xe

Pure samples of (131m)Xe, (133m)Xe, (133)Xe and (135)Xe facilitate the calibration and testing of noble gas sampler stations and related laboratory instrumentation. We have earlier reported a Penning trap-based production method for pure (133m)Xe and (133)Xe samples. Here we complete the work by reporting the successful production of pure (131m)Xe and (135)Xe samples using the same technique. In addition, we present data on xenon release from graphite.

Pathological subtrochanteric fractures in 194 patients: a comparison of outcome after surgical treatment of pathological and non-pathological fractures

BACKGROUND

The surgical treatment of pathological subtrochanteric fractures has been associated with technical difficulties and frequent failures. We analyzed survival, risk factors for death, and outcome after surgical treatment.

METHODS

The study group consisted of 194 patients with pathological subtrochanteric femur fractures operated during 1999-2009. Cox multiple-regression analysis was performed to study risk factors and results were expressed as hazard ratios (HR). We included a control group with non-pathological subtrochanteric fractures (n = 87) for comparison.

RESULTS

The median age at surgery was 68 (29-96) years in the study group and 82 (66-101) in the controls. The 1-year survival rate after surgery was 33% (95% CI: 26-40) in the study group and 85% (79-93) in the controls. In the study group, the risk of death after surgery was increased for patients ≥65 years of age (HR 1.5, 95% CI: 1.1-2.1), with a moderate (HR 2.2, 1.5-3.4) and poor (HR 2.9, 1.6-5.2) Karnofsky score, with visceral metastases (HR 1.6, 1.1-2.3), and perioperative hemoglobin levels <100 g/L (HR 2.2, 1.3-3.7). In patients with pathological fractures, there was no statistically significant difference concerning reoperation rates comparing intramedullary nails (9%) with endoprostheses (6%; P = 0.3).

CONCLUSIONS

Surgery for pathological subtrochanteric femur fractures is a relatively safe and effective procedure.

Conservative treatment, plate fixation, or prosthesis for proximal humeral fracture. A prospective randomized study

Background

Proximal humerus fracture is the third most common fracture type after hip and distal radius fracture in elderly patients. A comprehensive study by Palvanen et al. demonstrated an increase in the annual fracture rate of 13.7% per year over the past 33 years. Should this trend continue, the fracture rate would triple over the next three decades. The increasing incidence of low-energy fractures raises questions about the optimal treatment in terms of functional outcome, pain, and rehabilitation time, as well as the economical impact. Despite the high incidence and costs of proximal humerus fractures, there is currently no valid scientific evidence for the best treatment method. Several publications, including a Cochrane review outline the need for high-quality, well-designed randomized controlled trials.

Methods/Design

The study is a prospective, randomized, national multi-center trial. The hypothesis of the trial is that surgical treatment of displaced proximal humerus fractures achieves better functional outcome, pain relief, and patient satisfaction compared to conservative treatment. The trial is designed to compare conservative and surgical treatment of proximal humerus fractures in patients 60 years and older. The trial includes two strata. Stratum I compares surgical treatment with locking plates to conservative treatment for two-part fractures. Stratum II compares multi-fragmented fractures, including three- and four-part fractures. The aim of Stratum II is to compare conservative treatment, surgical treatment with the Philos locking plate, and hemiarthroplasty with an Epoca prosthesis. The primary outcome measure will be the Disabilities of the Arm, Shoulder and Hand (DASH) score and the secondary outcome measures will be the EuroQol-5D (EQ-5D) value, OSS, Constant-Murley Score, VAS, and 15D.

Recruiting time will be 3 years. The results will be analyzed after the 2-year follow-up period.

Discussion

This publication presents a prospective, randomized, national multi-center trial. It gives details of patient flow, randomization, aftercare and also ways of analysis of the material and ways to present and publish the results.

Trial registration

ClinicalTrials.gov identifier: NCT01246167

Complications and survival after surgical treatment of 214 metastatic lesions of the humerus

BACKGROUND

The humerus is the second most common long-bone site of metastatic bone disease. We report complications, risk factors for failure, and survival of a large series of patients operated on for skeletal metastases of the humerus.

MATERIALS AND METHODS

This study was based on 208 patients treated surgically for 214 metastatic lesions of the humerus. Reconstructions were achieved by intramedullary nails in 148, endoprostheses in 35, plate fixation in 21, and by other methods in 10.

RESULTS

The median age at surgery was 67 years (range, 29-87 years). Breast cancer was the primary tumor in 31%. The overall failure rate of the surgical reconstructions was 9%. The reoperation rate was 7% in the proximal humerus, 8% in the diaphysis, and 33% in the distal part of the bone. Among 36 operations involving an endoprosthesis, 2 were failures (6%) compared with 18 of 178 osteosynthetic devices (10%). In the osteosynthesis group, intramedullary nails failed in 7% and plate fixation failed in 22%. Multivariate Cox regression analysis showed that prostate cancer was associated with an increased risk of failure after surgery (hazard ratio, 7; P < 0.033). The cumulative survival after surgery was 40% (95% confidence interval [CI] 34-47) at 1 year, 21% (95% CI, 15-26) at 2 years, and 16% (95% CI, 12-19) at 3 years.

CONCLUSIONS

Our method of choice is the cemented hemiprosthesis for pathologic proximal humeral fractures and interlocked intramedullary nail for lesions in the diaphysis. Pathologic fractures in the distal humerus are uncommon and associated with a very high reoperation rate.

Rat Skeletal Muscle Myoblasts are Target Cells for the Action of Native Bone Morphogenetic Protein

Bone morphogenetic proteins (BMPs) are multifunctional proteins capable of inducing an osteogenic phenotype in various cell lines and providing alternatives to bone grafts in the field of orthopaedics. Study was carried out here of the specific binding and stimulation of markers of bone metabolism by highly purified native bovine BMP in rat skeletal myoblasts (L6). Binding studies using 125I-labeled BMP and various concentrations of unlabeled BMP showed the existence of a single-class, one-binding-site BMP receptor. The binding was time-, temperature- and dose-dependent in various experiments. In assessing the capacity of BMP to induce myoblasts to differentiate into the osteoblast lineage, osteocalcin production was initiated, alkaline phosphatase activity increased approximately four-fold and calcium uptake almost three-fold compared with control cells during four days culturing with 12.5 μg/ml of BMP. These results indicate that the L6 myoblast is a target cell for the action of native BMP, and under the influence of BMP L6 myoblasts are capable of differentiating in the direction of osteoblasts. This BMP-induced differentiation of myoblasts offers a novel assay system for in vitro detection of osteoinductivity and investigation of the mechanism of ectopic bone formation.

Soluble Factors from Human Saos-2 Osteosarcoma Cells Induce Ectopic Bone Formation and Osteoblastic Differentiation of Cultured Mesenchymal Cells

Freeze-dried cells of the human osteosarcoma cell line Saos-2 have the capacity to induce bone formation. We studied the bone-inductive capacity of factors expressed by Saos-2 cells and secreted to a growth medium. When lyophilized Saos-2-conditioned medium was implanted in a mouse hamstring muscle pouch, new bone formation was observed. Unlike the radially symmetric cartilage usually seen in induced ossicles, an asymmetric morphology of the newly formed bone was observed, with hyaline cartilage on one side and fibrocartilage on the other side. The new bone area resembled histologically osteochondroma, a benign bone tumor, with flat chondrocyte-like cells arranged in rows, endochondral ossification and red bone marrow. Osteoinductivity was further confirmed in in vitro tests with mesenchymal cell lines. A serum-free ten-fold concentrated Saos-2 growth medium increased mineralization, measured as 45Ca incorporation, and also stimulated alkaline phosphatase activity in cultured rat myoblasts and mouse embryo cells. These in vitro results indicate that Saos-2 cells secrete factors, among which is BMP-2/4, which stimulate mesenchymal cell differentiation to osteoblastic lineage.

The Effect of Cyclosporine a On Xenogeneic Moose (Alces Alces) Bone Morphogenetic Protein-Induced Immune Inhibition of Heterotopic Osteoinduction in the Rat Guided Muscle Island Flap Bioassay Model

Experimental heterotopic osteoinduction can be induced to take place in a pre-determined intramuscular space using a standard-sized membrane cylinder around a vascular muscle island flap, and implanting an osteoinductive agent such as bone morphogenetic protein (BMP) and demineralized bone matrix (DBM) inside the flap. This kind of newly introduced guided muscle assay method, analyzed by radiomorphometry and histology, was used to study quantitative differences in the osteoinductive activities of xenogenic moose BMP (mBMP) and allogeneic DBM in the Wistar rat, as well as the effect of cyclosporine A (CyA).

Calcified tissue in the flaps was quantified by computerized radiomorphometry at 21 days from implantation in five experimental groups: 1) partially purified mBMP; 2)mBMP with CyA treatment; 3) mBMP Plus active allogeneic DBM with CyA; 4) active allogeneic DBM alone; and 5) inactive DBM (control). The results were presented as radiopacity percentages of normal rat femoral bone values (=100). New bone formation was confirmed by microscopy of hematoxylin-eosin and azure II-stained samples.

The mean radiopacity, compared to mean rat femoral bone values (=100%), in the mBMP group was 20%. This did not significantly exceed the result in the control flaps with inactive DBM. When CyA was administered perorally to mBMP-implanted animals, the radiopacity increased from 20% to 35% ( p =0.026). When active allogeneic DBM was added to this combination, the increase was up to 53% ( p =0.002). Implantation of active allogeneic DBM alone gave 60%. In microscopy, cartilage was the main sign of tissue transformation in the mBMP-implanted groups without DBM, and new bone with marrow in the active allogeneic DBM-implanted groups. In the control flaps with inactive DBM, no bone or cartilage developed.

The quantity of new bone formation with mBMP could be significantly improved with CyA, but not to the superior level induced by active allogeneic DBM. The findings were explained by the marked immunogenicity of xenogeneic partially purified BMP.

The advantage of the new model, compared to the conventional intramuscular assays, is a reduction of variability in soft tissue intensities of the measured objects. The standard volume reserved for osteoinduction to take place will make the model also eminently suitable for histomorphometry.

Expression of matrix metalloproteinases-2, -8, -13, -26, and tissue inhibitors of metalloproteinase-1 in human osteosarcoma

Osteosarcoma (OS) is among most common malignant tumour of bone. Matrix metalloproteinases (MMPs) are predominantly associated with poor prognosis of several cancers, although some of them, like MMP-8, seem to have a protective role in some cancers. We analyzed the distribution patterns of MMP-2, -8, -13, -26, and tissue inhibitor of matrix metalloproteinase (TIMP)-1 in 25 OS patients. MMP-2, -8, -13, -26 and TIMP-1 were mostly detected in sarcoma cells. Response to chemotherapy affected the amount of MMP-2, -8, and -13 in resection sections when compared to biopsies: patients with excellent or good response had less positivity to MMP-2 in chemotherapy samples than those with moderate or poor response. We conclude that MMP-2, -8, -13, -26, and TIMP-1 are expressed in OS tissue, and all, except protective MMP-8, were also found in metastases indicating that MMPs and TIMP-1 can participate in the OS progression.

Lipid oxidation may reduce the quality of a fresh-frozen bone allograft. Is the approved storage temperature too high?

BACKGROUND

International standards indicate that bone allografts for human use should be stored in a -40 degrees C or colder environment and the storage time should be up to 5 years. Bone allografts contain lipids which oxidate and become toxic with time.

MATERIAL AND METHODS

We determined lipid oxidation in femoral head bone allografts by headspace gas chromatography at different storage temperatures and storage times.

RESULTS

We found that lipid oxidation in fresh-frozen bone allograft was influenced by storage temperature and storage time. Lipid oxidation was significantly more rapid at -30 degrees C than at -70 degrees C. Even at -70 degrees C, however, some oxidation occurred but it was quite minimal after 3 years.

INTERPRETATION

Because of the negative effects of lipid oxidation, we recommend a storage temperature of -70 degrees C or lower for bone allografts.

Aneurysmal bone cyst of the index sesamoid

Sesamoid bone disorders are rare and usually are a result of trauma or degenerative causes. Tumors of the sesamoid bones of the hand are encountered less frequently. We report a case of an aneurysmal bone cyst of the radial index sesamoid of the hand. The tumor was treated successfully by sesamoid bone resection.

Treatment of primary malignant bone tumours of the distal tibia

We treated 15 patients with primary malignant bone tumours of the distal tibia of which 14 were treated by limb salvage surgery. Reconstructions were done by allografts with or without microvascular fibula transfer, by bone transport, by fibula transfer alone or by endoprosthetic replacement. The most successful methods were bone transport and endoprosthetic replacement. However, serious complications with deep infections leading to secondary amputation occurred in four patients and in all reconstruction groups. After a mean follow up of 7 years, no local recurrence occurred, and all patients were alive and free of disease. After radical resection, bone transport in defects less than 15 cm is a viable option. In larger defects in children, allograft with vascularised fibula is an acceptable alternative, but amputation still has a role in this group. In adults, endoprosthetic replacement with proper soft tissue coverage is a viable option in cases with large bony defects.

Oocyte-expressed genes affecting ovulation rate

From examination of inherited patterns of ovulation rate in sheep, several breeds have been identified with point mutations in two growth factor genes (BMP15 and GDF9) and a related receptor (ALK6) that are expressed in oocytes. Five different point mutations have been identified in the BMP15 gene, one in GDF9 and one in ALK6. Animals heterozygous for these mutations or heterozygous for two of these mutations or homozygous for the ALK6 mutation have higher ovulation rates (i.e. +0.6-10) than their wild-type contemporaries. Animals homozygous for the BMP15 or GDF9 mutations are sterile due to arrested follicular development from the primary stage of growth. The BMP15 and GDF9 mutations are thought to result in reduced levels of mature protein or altered binding to cell-surface receptors. In sheep, GDF9 mRNA is present in germ cells before and after ovarian follicular formation as well as throughout follicular growth, whereas BMP15 mRNA is found in oocytes only from the primary stage of growth. Also ALK6 together with related cell-surface receptors such as ALK5 and BMPRII mRNA are present in oocytes at most, if not all, stages of follicular growth. Both GDF9 and BMP15 proteins are present in follicular fluid indicating that they are secreted products. Immunisation of sheep with GDF9 or BMP15 peptides shows that both growth factors are essential for follicular development, ovulation and/or corpus luteum formation. In animals with the ALK6 mutation, ovarian follicles undergo precocious maturation leading to three to seven follicles ovulating at smaller diameters without any increase above wild-types in the ovarian secretions of steroid or inhibin. One important consequence of the ALK6 mutation appears to be a decreased ability of some BMPs to inhibit differentiation of follicular cells. Current findings in sheep suggest that BMP15, GDF9 and ALK6 are targets for new methods of fertility regulation in some mammals.

The oocyte and its role in regulating ovulation rate: a new paradigm in reproductive biology

Ovulation rate in mammals is determined by a complex exchange of hormonal signals between the pituitary gland and the ovary and by a localised exchange of hormones within ovarian follicles between the oocyte and its adjacent somatic cells. From examination of inherited patterns of ovulation rate in sheep, point mutations have been identified in two oocyte-expressed genes, BMP15 (GDF9B) and GDF9. Animals heterozygous for any of these mutations have higher ovulation rates (that is, + 0.8–3) than wild-type contemporaries, whereas those homozygous for each of these mutations are sterile with ovarian follicular development disrupted during the preantral growth stages. Both GDF9 and BMP15 proteins are present in follicular fluid, indicating that they are secreted products.In vitrostudies show that granulosa and/or cumulus cells are an important target for both growth factors. Multiple immunisations of sheep with BMP15 or GDF9 peptide protein conjugates show that both growth factors are essential for normal follicular growth and the maturation of preovulatory follicles. Short-term (that is, primary and booster) immunisation with a GDF9 or BMP15 peptide-protein conjugate has been shown to enhance ovulation rate and lamb production. In summary, recent studies of genetic mutations in sheep highlight the importance of oocyte-secreted factors in regulating ovulation rate, and these discoveries may help to explain why some mammals have a predisposition to produce two or more offspring rather than one.

The Scandinavian Sarcoma Group Skeletal Metastasis Register. Survival after surgery for bone metastases in the pelvis and extremities

INTRODUCTION

The assessment of the prognosis for the individual patient is important for the choice of surgical treatment of skeletal metastases. In 1999 the Scandinavian Sarcoma Group (SSG) initiated the Skeletal Metastasis Register as a multicentric, prospective study to provide a scientific basis for treatment recommendations. To improve prognostication we analyzed the survival of patients with skeletal metastases surgically treated at 9 SSG centres.

PATIENTS AND METHODS

460 patients with an average age of 64 years underwent 501 operations for non-spinal skeletal metastases. 7% were operated for more than one metastasis. Carcinoma of the breast, prostate, kidney and lung were the dominating primary tumors.

RESULTS

The survival rate was 0.4 at 1 year, 0.3 at 2 years and 0.2 at 3 years. Univariate analysis showed that survival was related to bone localization, skeletal metastatic load, presence of visceral metastases, Karnofsky performance score, primary tumor type, presence of a complete pathological fracture and preoperative hemoglobin content. Multivariate regression analysis showed that pathological fracture, visceral metastases, haemoglobin content < 7 mmol/L and lung cancer were negative prognostic factors for survival. Myeloma was the sole positive prognostic factor for survival.

Cefuroxime, rifampicin and pulse lavage in decontamination of allograft bone

The risk of bacterial infection through allogenic bone transplantation is one of the major problems facing tissue banks. Different screening methods and decontamination procedures are being used to achieve a safe surgical result. The purpose of this study was to investigate the contamination rate in fresh frozen bone allografts after treating them with different decontamination methods. The allografts were contaminated by rubbing on the operating theatre floor for 60 min, after which they were rinsed either with sterile physiological saline, cefuroxime or rifampicin solution or they were washed with low-pressure pulse lavage of sterile physiological saline. Our findings show that low-pressure pulse lavage with sterile saline solution is very effective in removing bacteria from bone allograft, when compared with the antibiotic solutions tested.

Inhibition of matrix metalloproteinase-14 in osteosarcoma cells by clodronate

BACKGROUND

Bisphosphonates reduce the bone metastasis formation and angiogenesis but the exact molecular mechanisms involved are unclear. Progelatinase A (proMMP-2; 78 KDa) is activated up during the tumor spread and metastasis by a cell surface-associated matrix metalloproteinase (membrane-type matrix metalloproteinase [MT1-MMP] or MMP-14).

MATERIAL AND METHODS

We evaluated the effects of a bisphosphonate (clodronate) on MT1-MMP mRNA expression and protein production, catalytic activity and proteolytic activation of proMMP-2 by cultured human MG-63 osteosarcoma cells.

RESULTS

Clodronate, at therapeutically attainable noncytotoxic concentrations, dose-dependently inhibited phorbol myristic acetate (PMA)-induced proteolytic activation of proMMP-2 by human MG-63 osteosarcoma cells. Clodronate also downregulated the PMA-induced expression of MT1-MMP mRNA and protein production in human MG-63 osteosarcoma cells, as evidenced by Northern analysis and fluorescent immunohistochemistry. Furthermore, clodronate inhibited directly and dose-dependently MT1-MMP activity, and the MT1-MMP inhibition by clodronate was reduced in the presence of an increased (5 mM) Ca(2+) concentrations when compared to physiological (1 mM) Ca(2+) concentrations.

CONCLUSION

We conclude that (1) the extracellular/cell-associated mechanism of bisphosphonate involves inhibition of MT1-MMP catalytic activity eventually by chelation, and that (2) intracellular mechanism involves downregulation of induced MT1-MMP mRNA and protein expression. The inhibition and downregulation of MT1-MMP by clodronate can be related to their ability to reduce MG-63 osteosarcoma cell invasion and spread. These findings may, at least in part, explain at molecular level the antitumor and antibone resorption activities of clodronate observed in clinical studies.

Survival of 25 osteoarticular allografts followed more than 10 years

An evaluation of the long-term survival rate of 25 osteoarticular allografts was made. Clinical analysis was based on the Mankin scale and the Musculoskeletal Tumor Society (MSTS) Grading system. After a mean follow-up time of 15 years 76% of the osteoarticular allografts had good or excellent rating. The MSTS scale revealed a mean score of 89% for those 20 grafts still functioning according to their primary purpose. Allograft related complications occurred in 32% of the cases being most common among malignant cases. Due to the rather good long-term results, osteoarticular allografts can still be recommended for hemicondylar allograft reconstruction in benign lesions.

Pulse lavage washing in decontamination of allografts improves safety

We analyzed the bacterial contamination rate of 140 femoral head allografts after rinsing the allografts in different decontamination solutions. Bacterial screening methods and cleansing effect of antibiotics (cefuroxime and rifampicin) and pulse lavage were compared. Swabbing and taking small pieces of bone for culture were the screening methods used. Both methods proved to be quite unreliable. Approximately one-fourth of the results were false negative. Culturing small pieces of bone gave the most accurate and reliable results and, therefore, can be recommended as a bacterial screening method. The use of antibiotics in allograft decontamination is controversial. In prophylactic use antibiotics include risks of allergic reactions and resistant development and our results in the present study show that antibiotics do not improve the decontamination any better than low-pressure pulse lavage with sterile saline solution. Therefore, pulse lavage with sterile saline solution can be recommended for allograft decontamination. Our results demonstrate that it decreases bacterial bioburden as effectively as the antibiotics without persisting the disadvantages.

Bisphosphonates inhibit stromelysin-1 (MMP-3), matrix metalloelastase (MMP-12), collagenase-3 (MMP-13) and enamelysin (MMP-20), but not urokinase-type plasminogen activator, and diminish invasion and migration of human malignant and endothelial cell lines

Bisphosphonates (clodronate, alendronate, pamidronate and zoledronate) at therapeutically attainable non-cytotoxic concentrations inhibited MMP-3, -12, -13 and -20 as well as MMP-1, -2, -8 and -9, but not urokinase-type plasminogen activator (uPA), a serine proteinase and a pro-MMP activator. Dose-dependent inhibition was shown by three independent MMP assays. The inhibition was reduced in the presence of an increased concentration of Ca(2+) when compared to physiologic Ca(2+) concentration. Alendronate inhibited the in vitro invasion (Matrigel) of human HT1080 fibrosarcoma and C8161 melanoma cells, and the random migration of these malignant and endothelial cell lines capable of expressing MMPs and uPA. The concentration of alendronate required to inhibit 50% of the activity (IC(50)=40-70 microM) of MMPs corresponded to the IC(50) of down-regulation of in vitro invasion and migration. The ability of bisphosphonates to down-regulate the in vitro invasion and random migration was comparable or slightly better in relation to the selective gelatinase inhibitor CTTHWGFTLC peptide. Alendronate but not CTTHWGFTLC peptide promoted the adhesion of HT1080 fibrosarcoma and C8161 melanoma cell lines on fibronectin. Bisphosphonates are broad-spectrum MMP inhibitors and this inhibition involves cation chelation. Bisphosphonates further exert antimetastatic, anti-invasive and cell adhesion-promoting properties, which may prevent metastases not only into hard tissues but also to soft tissues.