Osteosarcoma pre-diagnosed as another tumor: a report from the Cooperative Osteosarcoma Study Group (COSS).

PURPOSE: The course of osteosarcoma patients primarily treated as such has been well described. Little, however, is known about patients who were primarily treated assuming a different tumor diagnosis. METHODS: The database of the Cooperative Osteosarcoma Study Group COSS was searched (4.435 primary high-grade central osteosarcomas registered prior to 01/01/21). A different tumor entity had to have been assumed for at least one month after the initial diagnostic procedure before the correct diagnosis of osteosarcoma was finally made. Identified patients were analyzed for demographic, tumor-, and treatment-related factors as well as for survival outcomes. RESULTS: 37 patients were identified. They were a median of 19.7 (2.7-60.4) years old at first presentation and were more likely to be females than males (23:14). Bone cysts (n = 8), giant cell tumor of bone (n = 6), and osteoblastoma (n = 6) were the most frequent of 29/37 (78%) benign, chondrosarcoma and its variants (n = 6) the most frequent of 8/37 (22%) malignant original diagnoses. Tumors affected the extremities in 23 (62%), the trunk in 11 (30%), and the craniofacial bones in 3 (8%). Only one patient received systemic treatment while assuming the different diagnosis (1/37, 3%). The median time until the correct diagnosis of osteosarcoma was made was 8 months (range: 1 month-14.1 years). At that time, 6/37 (16%) presented with metastatic disease. All patients went on to receive chemotherapy, 17/37 (46%) neo-adjuvantly. Histologic response was only evaluated in 13/17 (76%) patients and was good (< 10% viable tumor) in only 4/13 (31%) patients. In 31/37 (84%) patients, a surgically complete resection of all macroscopically identified tumor manifestations could be achieved. Five-year overall and event-free survival rates at 5 years were 50.2% (standard error: 8.6%) and 42.6% (8.5%), respectively. CONCLUSION: Osteosarcoma may initially be misdiagnosed and hence subjected to inappropriate treatment including misguided surgery. Once diagnosed correctly, some of the affected patients may still be cured if finally treated according to modern osteosarcoma standards.

Extraosseous osteoblastoma: A rare cause of breast mass in a prepubertal girl.

Extraosseous osteoblastoma of the breast, a rare disease, was diagnosed in a prepubertal girl. After tumor excision, the patient recovered well and an optimal cosmetic result was achieved. Interdisciplinary discussions about the case are essential.

Survival and prognosis with osteosarcoma: outcomes in more than 2000 patients in the EURAMOS-1 (European and American Osteosarcoma Study) cohort.

BACKGROUND: High-grade osteosarcoma is a primary malignant bone tumour mainly affecting children and young adults. The European and American Osteosarcoma Study (EURAMOS)-1 is a collaboration of four study groups aiming to improve outcomes of this rare disease by facilitating randomised controlled trials. METHODS: Patients eligible for EURAMOS-1 were aged ≤40 years with M0 or M1 skeletal high-grade osteosarcoma in which case complete surgical resection at all sites was deemed to be possible. A three-drug combination with methotrexate, doxorubicin and cisplatin was defined as standard chemotherapy, and between April 2005 and June 2011, 2260 patients were registered. We report survival outcomes and prognostic factors in the full cohort of registered patients. RESULTS: For all registered patients at a median follow-up of 54 months (interquartile range: 38-73) from biopsy, 3-year and 5-year event-free survival were 59% (95% confidence interval [CI]: 57-61%) and 54% (95% CI: 52-56%), respectively. Multivariate analyses showed that the most adverse factors at diagnosis were pulmonary metastases (hazard ratio [HR] = 2.34, 95% CI: 1.95-2.81), non-pulmonary metastases (HR = 1.94, 95% CI: 1.38-2.73) or an axial skeleton tumour site (HR = 1.53, 95% CI: 1.10-2.13). The histological subtypes telangiectatic (HR = 0.52, 95% CI: 0.33-0.80) and unspecified conventional (HR = 0.67, 95% CI: 0.52-0.88) were associated with a favourable prognosis compared with chondroblastic subtype. The 3-year and 5-year overall survival from biopsy were 79% (95% CI: 77-81%) and 71% (95% CI: 68-73%), respectively. For patients with localised disease at presentation and in complete remission after surgery, having a poor histological response was associated with worse outcome after surgery (HR = 2.13, 95% CI: 1.76-2.58). In radically operated patients, there was no good evidence that axial tumour site was associated with worse outcome. CONCLUSIONS: In conclusion, data from >2000 patients registered to EURAMOS-1 demonstrated survival rates in concordance with institution- or group-level osteosarcoma trials. Further efforts are required to drive improvements for patients who can be identified to be at higher risk of adverse outcome. This trial reaffirms known prognostic factors, and owing to the large numbers of patients registered, it sheds light on some additional factors to consider.

A comparative study of intraoperative frozen section and alpha defensin lateral flow test in the diagnosis of periprosthetic joint infection.

Background and purpose - For decision-making (aseptic vs. septic), surgeons rely on intraoperatively available tests when a periprosthetic joint infection (PJI) cannot be confirmed or excluded preoperatively. We compared and evaluated the intraoperative performances of the frozen section and the alpha defensin lateral flow test in the diagnosis of PJI. Patients and methods - In this prospective study, consecutive patients with indicated revision surgery after arthroplasty were included. Patients were classified as having PJI using the MusculoSkeletal Infection criteria. The presence of alpha defensin was determined using the lateral flow test intraoperatively. During revision surgery, tissue samples were harvested for frozen and permanent section. Analysis of diagnostic accuracy was based on receiver-operating characteristics. Results - 101 patients (53 hips, 48 knees) were eligible for inclusion. Postoperatively, 29/101 patients were diagnosed with PJI, of which 8/29 cases were definitely classified as septic preoperatively. Of the remainder 21 septic cases, the intraoperative alpha defensin test and frozen section were positive in 13 and 17 patients, respectively. Sensitivities of the alpha defensin test and frozen section were 69% and 86%, respectively. The area under the curves of both tests showed a statistically significant difference (p = 0.006). Interpretation - The frozen section showed a significantly higher performance compared with the alpha defensin test and a near perfect concordance with the definitive histology, and therefore remains an appropriate intraoperative screening test in diagnosing PJI. Although the sensitivity of the alpha defensin test was lower compared with that of frozen section, this test is highly specific for confirming the diagnosis of PJI.

High-Grade Osteosarcoma of the Foot: Presentation, Treatment, Prognostic Factors, and Outcome of 23 Cooperative Osteosarcoma Study Group COSS Patients.

Osteosarcoma of the foot is a very rare presentation of a rare tumor entity. In a retrospective analysis, we investigated tumor- and treatment-related variables and outcome of patients registered in the Cooperative Osteosarcoma Study Group (COSS) database between January 1980 and April 2016 who suffered from primary high-grade osteosarcoma of the foot. Among the 23 eligible patients, median age was 32 years (range: 6-58 years), 10 were female, and 13 were male. The tarsus was the most commonly affected site (n=16). Three patients had primary metastases. All patients were operated: 5 underwent primary surgery and 18 received surgery following preoperative chemotherapy. In 21 of the 23 patients, complete surgical remission was achieved. In 4 of 17 patients, a poor response to neoadjuvant chemotherapy was observed in the resected primary tumors. Median follow-up was 4.2 years (range: 0.4-18.5). At the last follow-up, 15 of the 23 patients were alive and 8 had died. Five-year overall and event-free survival estimates were 64% (standard error (SE) 12%) and 54% (SE 13%), which is similar to that observed for osteosarcoma in general. Event-free and overall survival correlated with primary metastatic status and completeness of surgery. Our findings show that high-grade osteosarcoma in the foot has a similar outcome as osteosarcoma of other sites.

C-reactive protein: An independent predictor for dedifferentiated chondrosarcoma.

Dedifferentiated chondrosarcoma is a rare primary bone malignancy with a very poor prognosis. The aim of the study was to identify pretreatment serum markers as prognostic factors for the overall survival (OS) of patients with dedifferentiated chondrosarcoma. We retrospectively reviewed 33 patients with histologically confirmed dedifferentiated chondrosarcoma treated at our department from 1977 to 2015. Kaplan-Meier estimation, uni- and multivariable Cox proportional hazard model were performed to evaluate the association between serum markers such as the C-reactive protein and OS. In univariable analysis, CRP was strongly associated with OS (HR 1.35; 95%CI 1.13-1.61; p = 0.001). This association prevailed after adjustment for AJCC tumor stage (HR 1.31; 95%CI 1.02-1.57; p = 0.031) in multivariable analysis. In conclusion, our data gave evidence that baseline CRP is an independent predictor for OS in patients with dedifferentiated chondrosarcoma. CRP could be exploited for the clinical prediction of this disease in the future. © 2018 The Authors. Journal of Orthopaedic Research® Published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society. J Orthop Res 36:2797-2801, 2018.

Matrix-associated chondrocyte transplantation for reconstruction of articulating surfaces in the temporomandibular joint: a pilot study covering medium- and long-term outcomes of 6 patients.

OBJECTIVE: Matrix-associated chondrocyte transplantation is routinely used in joints of the extremities but not in the temporomandibular joint (TMJ). STUDY DESIGN: We report the first case series in 7 patients of a tissue engineering approach to regenerate severely degraded articulating surfaces in the TMJ by simultaneously completely resurfacing both the mandibular condyle and the articular eminence/glenoid fossa with a commercially available collagen sponge seeded with autologous cells stabilized within a fibrin matrix. To facilitate healing, we temporarily employed a silicone membrane to protect the engineered tissues. The indications for surgery were posttraumatic fibro-osseous ankylosis, ankylosing osteoarthritis, or late-stage osteoarthritis. RESULTS: Six of the patients were recalled for follow-up after 3 years 6 months to 12 years 1 month. The maximum incisal opening was 18.2 ± 9.2 mm (range, 9-33 mm) before and 31.2 ± 13.6 mm (range, 12-47 mm) at the latest follow-up. Histologic specimens taken at 4 months showed beginning differentiation of fibrocytes into chondrocytes, whereas at 3 and 11 years, mature hyaline cartilage-not typical for the TMJ-was present. CONCLUSIONS: We conclude that the reconstruction of TMJ surfaces by matrix-associated chondrocyte transplantation may become a routine method for cartilage regeneration in the TMJ in the future.

Increased zinc accumulation in mineralized osteosarcoma tissue measured by confocal synchrotron radiation micro X-ray fluorescence analysis.

Abnormal tissue levels of certain trace elements such as zinc (Zn) were reported in various types of cancer. Little is known about the role of Zn in osteosarcoma. Using confocal synchrotron radiation micro X-ray fluorescence analysis, we characterized the spatial distribution of Zn in high-grade sclerosing osteosarcoma of nine patients (four women/five men; seven knee/one humerus/one femur) following chemotherapy and wide surgical resection. Levels were compared with adjacent normal tissue. Quantitative backscattered electron imaging as well as histological examinations was also performed. On average, the ratio of medians of Zn count rates (normalized to calcium) in mineralized tumor tissue was about six times higher than in normal tissue. There was no difference in Zn levels between tumor fraction areas with a low fraction and a high fraction of mineralized tissue, which were clearly depicted using quantitative backscattered electron imaging. Moreover, we found no correlation between the Zn values and the type of tumor regression according to the Salzer-Kuntschik grading. The underlying mechanism of Zn accumulation remains unclear. Given the emerging data on the role of trace elements in other types of cancer, our novel results warrant further studies on the role of trace elements in bone cancer. Copyright © 2016 The Authors. X-Ray Spectrometry published by John Wiley & Sons Ltd.

Bacillary angiomatosis presenting with facial tumor and multiple abscesses: A case report.

BACKGROUND: The clinical manifestation of bacillary angiomatosis (BA) can be limited to one organ, most commonly the skin, but systemic courses can also occur. We report a human immunodeficiency virus (HIV)-positive patient with a systemic manifestation of BA caused by Bartonella quintana, diagnosed in Vienna, Austria. The pathogen was detected in multiple organs including a facial tumor which is an unusual finding for BA. Furthermore, infections with B quintana are rare in our area and no other autochthonous cases have been reported. METHODS AND RESULTS: The clinical manifestation included multiple papules and nodules on the entire body, several organic abscesses, and a facial tumor influencing the patient's view.The main laboratory finding indicated HIV infection combined with severe immunosuppression with 47 CD4 cells/µL. Contrast-enhanced computed tomography of the chest and the abdomen showed multiple and abscesses. Histological examination of the facial tumor confirmed inflammatory process. Bartonella quintana was detected by PCR in blood and in the facial tumor as well as by culture in the skin tissue. Antibiotic treatment with doxycycline and antiretroviral therapy resulted in clinical improvement. CONCLUSION: Our case shows that rare opportunistic, vector-borne infections, usually associated with poverty, can lead to diagnosis of HIV even in well-developed countries. Furthermore, we provide details on clinical manifestation and diagnostic work-up which might expand the knowledge on disseminated infections with B quintana. As far, tumorous deformations have rarely been reported as consequence of BA. In our patient the pathogen was detected in the facial tumor using PCR techniques.

Multiple relapses in high-grade osteosarcoma: when to stop aggressive therapy?

The prognosis after relapse of high-grade osteosarcoma is poor and complete resection of all tumors is essential for survival. A 6-year old was diagnosed with high-grade osteosarcoma and treated according to the COSS-96 protocol. Within 5 years from initial diagnosis, five osteosarcoma relapses occurred and every time it was possible to achieve complete surgical remission. Additional treatments included chemotherapy and dendritic cell-based cancer immune therapy. Since the end of therapy of the 5th relapse, he is alive for 11½ years. Our experience further supports that aggressive surgery can help to achieve long-term survival even in patients with multiple osteosarcoma relapses.

Tumour response of osteosarcoma to neoadjuvant chemotherapy evaluated by magnetic resonance imaging as prognostic factor for outcome.

PURPOSE: This study evaluated the feasibility of computed magnetic resonance imaging (MRI) volumetry in conventional osteosarcomas. Secondly, we investigated whether computed volumetry provides new prognostic indicators for histological response of osteosarcomas after neoadjuvant chemotherapy. METHODS: In a retrospective cohort study, data from the Vienna Bone Tumour Registry was used. MR images from 14 patients (male:female = 1.8, mean age 19 years) were analysed prior to and after neoadjuvant chemotherapy according to current therapy regimens. Histological response to chemotherapy was graded according to the Salzer-Kuntschik classification. Computed volumetry was performed for the intraosseous part, as well as the soft-tissue component and the tumour as a whole. RESULTS: In a setting of appropriate radiological equipment, the method has been considered to be well implementable into clinical routine. The mean tumour volume prior to chemotherapy was 321 (±351) ml. In good responders (n = 6), overall tumour volume decreased by 47% (p = 0.345), whereas poor responders (n = 8) showed a 19% decrease (p = 0.128). Neoadjuvant multidrug therapy remarkably changed the tumour composition. This is seen in a decrease of the mean ratio of soft-tissue to intraosseous tumour volume from 8.67 in poor responders and 1.15 in good responders to 1.26 and 0.45 (p = 0.065), respectively. Interestingly, the bony compartment of good responders showed a volume increase during neoadjuvant chemotherapy (p = 0.073). However, we did not find prognostic markers for histological tumour response to pre-operative chemotherapy. CONCLUSIONS: Separated volumetry of tumour segments revealed interesting insights into therapy-induced growth patterns. If verified in a larger study population, these results should be taken into account when planning ablative surgery.

Vacuum inversion and securing of distal colonic pseudodiverticula with novel spiked O-rings.

BACKGROUND: Diverticular disease is increasingly prevalent in Western societies and is associated with significant morbidity. OBJECTIVE: Two-stage endoscopic device development for inversion and secured ligation of colonic diverticula; first, human cadaver studies were performed to measure forces required for diverticular inversion; second, a novel set of devices (elastic spiked O-ring with delivery system) was tested in animals. DESIGN: Prospective, observational study of human cadavers and prospective, interventional study of a porcine model. SETTING: University hospital pathology laboratory and animal facility. INTERVENTION: Full-thickness inversion of the colonic wall with a pipelike delivery instrument to produce an inverted pseudodiverticulum that was secured with a spiked O-ring. MAIN OUTCOME MEASUREMENTS: The forces required for diverticular inversion, the secured closure of inverted pseudodiverticula, and the time until necrotic tissue falls off. RESULTS: A total of 248 of 248 of cadaveric sigmoid diverticula could be inverted by means of vacuum or forceps. The forces required for inversion ranged from 0.28 to 0.47 N (median, 0.37 N). Twenty-four spiked O-rings were delivered in 6 living pigs to produce 24 inverted pseudodiverticula. One animal died the day after the procedure of a pulmonary thromboembolism. In the remaining 5 pigs, all delivered spiked O-rings remained in place for 7 to 22 days. At necropsy, none of the inverted sites showed signs of perforation but rather full-thickness reparative scarring with ingrowth of connective tissue. LIMITATIONS: Animal model, stiff pipelike delivery instrument, variations in diverticular location, diameter, and size. CONCLUSIONS: Endoluminal inversion and securing of colonic diverticula induces tissue necrosis, diverticular sloughing, and full-thickness scarring.

Surgical treatment of the haemophilic pseudotumour: a single centre experience.

PURPOSE: Haemophilic pseudotumour was defined by Fernandez de Valderrama and Matthews as a progressive cystic swelling involving muscle, produced by recurrent haemorrhage into muscles adjacent to the bone. The pseudotumour mainly occurs in the long bones and the pelvis. The treatment of the haemophilic pseudotumour poses a challenge, and extensive clinical experience is essential to appropriately address this serious complication in patients with haemophilia. Consequently, the aim of this study is to present our own clinical experience and treatment results of the haemophilic pseudotumour. METHODS: We retrospectively reviewed the records of 87 patients with bleeding disorders treated between 1967 and 2011 for musculoskeletal complications of congenital bleeding disorders. We identified six patients with a haemophilic pseudotumour who were treated at our department. RESULTS: The mean age at surgery was 45.9 (range, 40-61) years. The iliac bone was affected in three patients (one right, two left), the right tibia (distal diaphysis) in one, the right thigh in two and the right ulna (proximal part) in one patient. One patient had two pseudotumours. The perioperative course was easily controllable with adequate factor VIII substitution. At the latest follow-up after 8.4 (range, 4-24) years, normal healing with no recurrence was observed. CONCLUSIONS: The haemophilic pseudotumour is a rare but severe complication of hereditary bleeding disorders. In the international literature the resection and postoperative course are described as challenging and difficult, requiring detailed preoperative planning. It is advisable to perform such operations in specialised centres with close co-operation between surgeons and haematologists.

Growth potential of different zones of the growth plate-an experimental study in rabbits.

Despite clinical efforts to treat growth disturbances only little is known about the growth potential of the different zones of the growth plate. The aim of this study was to investigate the growth potential of different zones of the growth plate. A total of 20 New Zealand White rabbits were used for this experiment. The right and left ulna of each animal were used resulting in a total of 40 ulnae. Animals were assigned into five groups. In groups I and II resection of the metaphyseal (n = 12) or the epiphyseal (n = 6) segment of the growth plate was performed. In group III resection of the growth plate and re-implantation was performed (n = 6). In group IV the growth plate was resected and re-implanted after a 180° rotation (n = 6). Animals in group V served as controls. Histologic and radiologic examinations were performed to evaluate the growth process at 1, 2, 4, and 12 weeks following surgery. In group I, III, and IV temporary growth disturbance which was compensated within a short time was observed. Resection of the epiphyseal part resulted in growth arrest of the distal ulna in combination with normal growth of the radius which led to and valgus deformity of the limb. The results of this study indicate the importance of the reserve zone for the functioning of the growth plate.

The effect of drilling and screw fixation of the growth plate--an experimental study in rabbits.

Injury of the growth plate is a specific problem in traumatology and can cause limb deformity and length discrepancy as a result of growth arrest. The purpose of this study was to evaluate alterations of the growth plate after artificially created injuries. A total of 14 New Zealand White rabbits were used for this experiment. The right and left ulna of each animal was used resulting in a total of 28 ulnae. In six animals drill holes were driven into the growth plate either from the distal/epiphyseal side or from the proximal/metaphyseal side of the physis. In six animals a fracture of the distal ulna corresponding to a Salter-Harris fracture type IV was created. This fracture was fixed by screws from either the epiphyseal or the metaphyseal side. Two animals served as controls. Histologic and radiologic examinations were performed to evaluate the growth process at 1, 2, 4, and 12 weeks following surgery. Drilling or fixation of the growth plate from the metaphyseal side resulted in temporary growth disturbance which was compensated within a short time. In contrast fixation from the epiphyseal side caused severe growth disturbances. Based on our findings K-wires or screws should be inserted from the metaphyseal side and be placed in the center of the growth plate.

Low-grade chondrosarcoma of bone: experiences from the Vienna Bone and Soft Tissue Tumour Registry.

In a retrospective single-centre study, 70 low-grade chondrosarcoma (LCS) (31 female/39 male patients with a mean age of 40 years) were reviewed to evaluate surgical management. The mean overall follow-up was 81 months (median: 73 months, range: 6-317 months). Seventeen lesions (24.3%) in the trunk and 53 (75.7%) in the extremities were treated by curettage (48.6%) or resection (51.5%). Local recurrence occurred in eight patients (11.4%) 18 months postoperatively (median: 18 months, range: 0-41 months). Recurrence-free survival was significantly better for patients with extremity lesions compared to truncal lesions, but was not affected by resection margin. The anatomical site "trunk" and an "intralesional" resection margin had a significant independent prognostic influence in multivariate analysis. Curettage with local adjuvants is a viable treatment option for most extremity LCS. In truncal LCS wide resection is recommended despite a potentially higher complication rate.

Osteosarcoma in very young children: experience of the Cooperative Osteosarcoma Study Group.

BACKGROUND: This study was conducted to investigate presentation, treatment, and outcome in very young children with osteosarcoma. METHODS: The authors retrospectively analyzed the data of 2706 consecutive COSS patients with newly diagnosed osteosarcoma and identified 28 (1.0%) patients aged younger than 5 years at diagnosis. Demographic, diagnostic, tumor, treatment-related variables, response, and survival data were analyzed. RESULTS: Of the 28 preschoolers, 27 presented with high-grade central osteosarcoma of an extremity, and 1 had a secondary osteosarcoma of the orbit. This analysis focused on the 27 patients with extremity tumors. The size of the primary was large (≥one-third of the involved bone) in 20 of 27 patients. Primary metastases were detected in 4 of 27 children. All patients received multiagent chemotherapy, and 11 of 18 analyzed tumors responded well (>90% necrosis) to neoadjuvant chemotherapy. Limb-sparing surgery was performed in 9 cases, ablative procedures were performed in 15, and, in 3 cases, no local surgery was performed. With a median follow-up of 4 years (6.2 years for survivors), 13 patients were alive. Four patients never achieved a complete remission, and 11 developed recurrences; 14 of these 15 patients died. Five-year overall and event-free survival probabilities were 51% (standard error of the mean [SE], 10%) and 48% (SE, 10%). Better survival was correlated with good response to chemotherapy and later time period of diagnosis. CONCLUSIONS: Osteosarcoma is extremely rare in preschool children. These patients often have large tumors that may require mutilating resections. Prognosis is in the range of that reported for older patients.

Intimal sarcoma of the pulmonary valve.

Pulmonary artery intimal sarcoma is a rare tumor of the cardiovascular system. Intimal sarcoma of the pulmonary valve itself has not been described. Embolization into pulmonary arteries originating from the pulmonary valve intimal sarcoma can mimic chronic thromboembolic pulmonary hypertension and mislead the diagnosis. We present and discuss a patient initially diagnosed as chronic thromboembolic pulmonary hypertension, treated by pulmonary endarterectomy. After 24 months, a tumor of the pulmonary valve was detected by echocardiography. The patient underwent removal and replacement of the pulmonary valve. Histology revealed pulmonary valve intimal sarcoma.

Histological evaluation of the healing potential of the anterior cruciate ligament by means of augmented and non-augmented repair: an in vivo animal study.

The purpose of this animal study was to investigate the healing potential of the anterior cruciate ligament following transaction at the femoral end, by means of both the augmented and the nonaugmented primary repair, focusing on the histological changes during a 12-month postoperative observation period with respect to necrosis and the loss of normal structures during the healing period. Twenty sheep were randomly assigned to nonaugmented primary ACL repair, or to augmented ACL repair using a polyethylene terephthalate (PET) band. At 2, 6, 16, 26 and 52 weeks postoperatively four sheep out of each group were sacrificed. Histological healing was achieved after 16 weeks for the augmented repair group and after 26 weeks for the nonaugmented repair group. The main difference between the two techniques was that the PET augmentation device protected the ligament from necrosis and ligamentization. In this group a consistently normal ligament was seen histologically during the entire postoperative observation period. The nonaugmented repaired ACLs underwent the processes of necrosis and ligamentization.

Running has a negative effect on bone metabolism and proinflammatory status in male aged rats.

Animal models for male osteoporosis are scarce. This study aimed at identifying the impact of different living conditions on bone structure and metabolism as well as the inflammatory status in a rat model of age-related male osteoporosis. Bone mineral density, bone histomorphometric data, ex vivo osteoclast generation, and bone metabolism serum marker as well as intracellular cytokine expressions were evaluated in 23-month-old male Sprague-Dawley rats subjected to different housing conditions from the age of 5 months. Running rats were housed individually and were exercised voluntarily in running wheels attached to their cages. Dieting rats were housed individually, too, but were fed to pair weight with the running rats. Walking rats were exercised mildly by use of a treadmill (800m/day, 5 days a week) and social rats were kept as four in a cage and fed ad libitum. Whereas no marked differences could be found for bone mineral density, trabecular bone volume as well as trabecular bone surface were diminished in walking rats. The ex vivo osteoclast generation assay revealed no significant differences between groups. Osteoblasts of running rats were not only decreased in number, but displayed also a lower activity as indicated by decreased serum osteocalcin levels. Osteoclast activity was increased in the same group as indicated by elevated CTX (c-terminal telopeptide of type I collagen) levels. Additionally, production of tumor necrosis factor (TNF)-alpha and interferone (IFN)-gamma by CD8(+) T cells was elevated in running rats. In conclusion, running has a negative effect on bone metabolism and proinflammatory status in male aged rats.