Pigmented villo-nodular synovitis and giant-cell tumor of tendon sheaths: a binational retrospective study.

AIM: Pigmented villonodular synovitis is rare. Thus, we initiated a retrospective multi-center study regarding symptoms, location, type of disease, type of surgery, number of recurrences, use of adjuvant therapies and functional outcome. RESULTS: Ten centers contributed. Data from 173 patients were sampled. The disease was seen predominantly in joints, less frequently in tendon sheaths and bursae. Patients with articular lesions suffered mainly from the diffuse type. In tendon sheaths, the relation "diffuse versus nodular" was nearly 50 % each, in bursae most often the nodular type was found. Anatomically, mostly the knee was affected. Institutions with more than 20 patients had a lower rate of recurrence than those with less than 20 cases. Regarding the knee, there were less recurrences in joints treated with open synovectomy than in those treated arthroscopically. CONCLUSIONS: Since the rate of recurrence has been rather high, the use of adjuvant treatments (radiosynoviorthesis or radiotherapy) is recommended. In our study, the rate of their application was quite low. Patients who received an adjuvant therapy after primary surgery did not show any recurrence. In 14 % of patients in whom an adjuvant therapy had been used, after at least one recurrence, further recurrences were observed. Functional results were excellent in 84 % of patients. LEVEL OF EVIDENCE: Prognostic multi-center study, Level III.

The influence of tumor- and treatment-related factors on the development of local recurrence in osteosarcoma after adequate surgery. An analysis of 1355 patients treated on neoadjuvant Cooperative Osteosarcoma Study Group protocols.

BACKGROUND: Local recurrence (LR) in osteosarcoma is associated with very poor prognosis. We sought to evaluate which factors correlate with LR in patients who achieved complete surgical remission with adequate margins. PATIENTS AND METHODS: We analyzed 1355 patients with previously untreated high-grade central osteosarcoma of the extremities, the shoulder and the pelvis registered in neoadjuvant Cooperative Osteosarcoma Study Group trials between 1986 and 2005. Seventy-six patients developed LR. RESULTS: Median follow-up was 5.56 years. No participation in a study, pelvic tumor site, limb-sparing surgery, soft tissue infiltration beyond the periosteum, poor response to neoadjuvant chemotherapy, failure to complete the planned chemotherapy protocol and biopsy at a center other than the one performing the tumor resection were significantly associated with a higher LR rate. No differences were found for varying surgical margin widths. Surgical treatment at centers with small patient volume and additional surgery in the primary tumor area, other than biopsy and tumor resection, were significantly associated with a higher rate of ablative surgery. CONCLUSIONS: Patient enrollment in clinical trials and performing the biopsy at experienced institutions capable of undertaking the tumor resection without compromising the oncological and functional outcome should be pursued in the future.

Medium to long-term results after reconstruction of bone defects at the knee with tumor endoprostheses.

BACKGROUND AND OBJECTIVES: Limb salvage and reconstruction with tumor endoprostheses is considered as therapeutic standard in the treatment of bone defects at the knee. Few studies report long-term results so far. METHODS: Seventy-seven patients who had a cementless or cemented MUTARS endoprosthesis implanted were followed-up for a mean period of 46 months (3-128 months). The defects were due to primary tumor lesions in 69 cases or metastases in 8 cases. The distal femur (n = 49) or the proximal tibia (n = 28) was reconstructed predominantly with cementless implants (femur: 69%, tibia: 92%). The resection of the tumor was intraarticular in 46 and extraarticular in 31 patients. RESULTS: After 10 years probability of limb salvage was 92% with a recurrence rate of 3%. Complications were frequent with a revision rate of 58% and lead to a cumulative probability of survival of the initially implanted prosthesis of 57% after 5 years. Locking mechanism failure (n = 15) and aseptic loosening (n = 13) were the most frequent failure modes. CONCLUSIONS: Regardless of achieving a low recurrence rate and satisfactory functional results, we found a high complication rate after implantation of a megaprosthesis. This was particularly evident for extraarticular resections and cemented fixation, which should be avoided when possible.

Can spinopelvic mobility be predicted in patients awaiting total hip arthroplasty? A prospective, diagnostic study of patients with end-stage hip osteoarthritis.

AIMS: This study of patients with osteoarthritis (OA) of the hip aimed to: 1) characterize the contribution of the hip, spinopelvic complex, and lumbar spine when moving from the standing to the sitting position; 2) assess whether abnormal spinopelvic mobility is associated with worse symptoms; and 3) identify whether spinopelvic mobility can be predicted from static anatomical radiological parameters. PATIENTS AND METHODS: A total of 122 patients with end-stage OA of the hip awaiting total hip arthroplasty (THA) were prospectively studied. Patient-reported outcome measures (PROMs; Oxford Hip Score, Oswestry Disability Index, and Veterans RAND 12-Item Health Survey Score) and clinical data were collected. Sagittal spinopelvic mobility was calculated as the change from the standing to sitting position using the lumbar lordosis angle (LL), sacral slope (SS), pelvic tilt (PT), pelvic-femoral angle (PFA), and acetabular anteinclination (AI) from lateral radiographs. The interaction of the different parameters was assessed. PROMs were compared between patients with normal spinopelvic mobility (10° ≤ ∆PT ≤ 30°) or abnormal spinopelvic mobility (stiff: ∆PT < ± 10°; hypermobile: ∆PT > ± 30°). Multiple regression and receiver operating characteristic (ROC) curve analyses were used to test for possible predictors of spinopelvic mobility. RESULTS: Standing to sitting, the hip flexed by a mean of 57° (sd 17°), the pelvis tilted backwards by a mean of 20° (sd 12°), and the lumbar spine flexed by a mean of 20° (sd 14°); strong correlations were detected. There was no difference in PROMs between patients in the different spinopelvic mobility groups. Maximum hip flexion, standing PT, and standing AI were independent predictors of spinopelvic mobility (R2 = 0.42). The combined thresholds for standing was PT ≥ 13° and hip flexion ≥ 88° in the clinical examination, and had 90% sensitivity and 63% specificity of predicting spinopelvic stiffness, while SS ≥ 42° had 84% sensitivity and 67% specificity of predicting spinopelvic hypermobility. CONCLUSION: The hip, on average, accounts for three-quarters of the standing-to-sitting movement, but there is great variation. Abnormal spinopelvic mobility cannot be screened with PROMs. However, clinical and standing radiological features can predict spinopelvic mobility with good enough accuracy, allowing them to be used as reliable screening tools. Cite this article: Bone Joint J 2019;101-B:902-909.

Knock-down of oncohistone H3F3A-G34W counteracts the neoplastic phenotype of giant cell tumor of bone derived stromal cells.

Giant cell tumors of bone (GCTB) are semi-malignant tumors associated with extensive osteolytic defects and massive bone destructions. They display a locally aggressive behavior and a very high recurrence rate. Recently, a single mutation has been identified in GCTB affecting the H3F3A gene coding for the histone variant H3.3 (H3.3-G34W). The aim of this study was to investigate whether H3.3-G34W is sufficient to drive tumorigenesis in GCTB. Initially, we confirmed the high frequency of this mutation in 94% of 84 analyzed tissue samples. Using a siRNA based approach we could selectively knockdown H3.3-G34W in primary neoplastic stromal cells isolated from tumor tissue (GCTSC). H3.3-G34W knockdown caused a significant inhibition of cell proliferation, migration and colony formation capacity in vitro. Xenotransplantation of GCTSCs onto the chorioallantoic membrane of fertilized chicken eggs further demonstrated a significant impact of H3.3-G34W knockdown on tumor engraftment and growth in vivo. Our data indicate that H3.3-G34W is sufficient to drive tumorigenesis in GCTB. Apart from the application of H3.3-G34W screening as diagnostic tool, our data suggest that H3.3-G4W represents a promising target for the development of new GCTB therapies.

[Current short- and long-term results of lumbar disc replacement : update 2008]. / Lumbale Bandscheibenendoprothetik - Update 2008 : Metaanalyse der Kurz- und Langzeitergebnisse.

Lumbar total disc replacement is an increasingly common way of treating degenerative lumbar disc disease while preserving mobility. The aim of this analysis was to survey evidence-based data to classify the procedure. Based on a MEDLINE inquiry, 38 clinical trials dealing with lumbar total disc replacement were selected and analyzed by the criteria of indication, preoperative procedure, and clinical follow-up. These data represent 3,180 patient-related evaluations with follow-up of 5.9 to 204 months. We also included ten retrospective studies. Patient satisfaction was a mean of 90.73%, and the Oswestry Disability Index and Visual Analog Scale were significantly lower. High rates of revision surgery, explantation surgery, and secondary fusions are linked to wrong preoperative indication. According to evidence criteria, the results show that lumbar total disc replacement is a safe procedure with a high rate of success. There is clear evidence that both imprecise indication and the choice of too-small implants significantly reduce the prospect of surgical success and increase the rates of reintervention.

[Experience in orthopaedic surgery with minimum provider volumes]. / Erfahrungen mit Mindestmengen in der Orthopädie.

The implementation of minimum provider volumes in orthopaedic surgery appears to be logically evident. A general volume outcome relationship could be found for total knee and hip replacement on a high level of evidence, but no definite threshold value could be identified. For other orthopaedic procedures the evaluated data hint at a volume outcome relationship but do not prove one. Preliminary model calculations on the effects of a regulation based on volume outcome considerations concerning medical care in Germany show that, though for total hip and knee replacement quite a large number of hospitals would be excluded from medical care, the number of patients to be reallocated would be small. Since 1 January 2007 a minimum provider volume of 50 total knee replacements per year per hospital has been mandatory in Germany. The further application of a minimum requirement regulation based on volume outcome considerations in the German health care system must be performed very carefully, because significant effects are to be expected.