Effects of electromagnetic fields on bone regeneration in experimental and clinical studies: a review of the literature / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To assess the experimental and clinical data regarding the effects of electromagnetic fields (EMFs) on fracture non-union.</p><p><b>DATA SOURCES</b>The English language literature regarding EMFs on fracture non-union were searched using MEDLINE, Web of Science and Embase, for the period January 2006 to June 2011. The search terms were electromagnetic fields and non-union/bone marrow stem cells (BMSCs)/bone.</p><p><b>STUDY SELECTION</b>Articles were included in the review if they were related to the use of EMFs on BMSCs or bone tissue. Papers without full manuscripts available were excluded.</p><p><b>RESULTS</b>The basic and clinical research in this field, while somewhat limited, supports the insightful application of EMFs to ameliorate disability due to fracture non-union.</p><p><b>CONCLUSIONS</b>Further basic and clinical research to validate the use of EMFs in facilitating function and bone reparative processes in fracture non-union is required.</p>

A preliminary report of patellofemoral arthroplasty in isolated patellofemoral arthritis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Isolated patellofemoral osteoarthritis is not uncommon. Surgical treatment of isolated patellofemoral arthritis remains controversial and poses a challenging treatment dilemma. The present study aimed to evaluate the short-term results of patellofemoral arthroplasty for patients with isolated patellofemoral osteoarthritis.</p><p><b>METHODS</b>We analyzed 11 patellofemoral arthroplasties performed from March 2006 to September 2009 in 11 patients with isolated patellofemoral arthritis. The patients comprised 2 males and 9 females with an average age of 53.7 years (range, 46 - 74 years). Standard weightbearing radiographs were taken in the anteroposterior, lateral, and 45° axial views. The knee pain and functional status were evaluated by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scales and American Knee Society (AKS) scores. For comparison, 23 total knee arthroplasties in 23 patients with primary tibiofemoral osteoarthritis were matched according to age, gender, bilaterality and body mass index. The duration of follow-up was 23.7 months (range, 12 - 47 months).</p><p><b>RESULTS</b>The majority of the 11 patients experienced improvement in their patellofemoral symptoms after patellofemoral arthroplasty. The WOMAC scores improved considerably by 7.4 points with respect to pain and by 5.2 points with respect to function. The AKS scores also improved considerably by 23.9 points with respect to pain and 44.3 points with respect to function. Although the clinical outcomes after patellofemoral arthroplasty were not better than those after total knee arthroplasty, patellofemoral arthroplasty exhibited advantages in the shorter operation time, lower blood loss and increased postoperative range of motion. At the latest follow-up, there was no clinical or radiographic evidence of patellofemoral maltracking, loosening or wear.</p><p><b>CONCLUSIONS</b>On the basis of our experience in this relatively small series of patients with a short-term follow-up, patellofemoral arthroplasty is an effective treatment alternative to total knee arthroplasty in isolated patellofemoral arthritis. MRI and arthroscopy may contribute to define those patients with isolated patellofemoral degeneration.</p>

Selection of allografts for impaction bone grafting for bone defect reconstruction on the acetabular side / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To review the choices of allografts for bone defect reconstruction in acetabular revision surgery using the technique of impaction bone grafting.</p><p><b>DATA SOURCES</b>The data cited in this review were mainly obtained from articles listed in PubMed that were published from January 1993 to July 2009. The search terms were "impaction bone grafting", "particle size", "mechanical property" and "biological behavior".</p><p><b>STUDY SELECTION</b>Articles relevant to the choices of allografts and their results for bone defect reconstruction on the acetabular side were selected.</p><p><b>RESULTS</b>Different choices of allografts, including the particle size, process of irradiation or fat reduction, composition and particle grade, are made to improve the survival rate of a prosthesis in acetabular revision surgery. This review, which compares both mechanical and biological factors, summarizes the experimental and clinical results for different techniques.</p><p><b>CONCLUSIONS</b>Fresh frozen cancellous allografts with particle sizes ranging from 7 to 10 mm are a favorable choice for reconstruction of bone defects of American Academy of Orthopedic Surgeons (AAOS) types II (cavitary defect) and III (combined cavitary and segmental defect) on the acetabular side. A fat-reducing procedure with saline or solvent/detergent is controversial. Adding autologous marrow into irradiated allografts, which provides reliable mechanical stability and biological safety, may be a substitute for fresh frozen allografts. Cortical bone can be a supplementary material in cases of insufficiency of cancellous allografts. Cartilage should be excluded from the graft material. Further research is required to demonstrate the best particle grade, and randomized controlled trials in clinical practice are required to obtain more information about the selection of allografts.</p>