Clinical course of masticatory function recovery following arthrocentesis in patients with unilateral mandibular condyle head fracture

The aim of this study was to investigate the clinical course of masticatory function recovery following arthrocentesis. Patients with a unilateral condylar head fracture who underwent arthrocentesis for therapeutic reasons were evaluated and compared with patients with a unilateral condylar head fracture who did not undergo arthrocentesis. At 3 months after treatment, the occlusal contact area and maximum bite force in patients with a fracture treated with arthrocentesis were greater than in those who did not receive arthrocentesis at the same time points, although the differences were not significant. Moreover, at 1 and 3 months following arthrocentesis, mean (±SD) occlusal contact area (1 month: 1.99 ± 0.55 mm², p = 0.01; 3 months: 2.90 ± 1.36 mm², p = 0.03) and maximum bite force (1 month: 82.45 ± 15.04 N, p = 0.01; 3 months: 101.11 ± 14.53 N, p = 0.01) on the fractured side in patients who underwent that treatment were significantly reduced when compared with those on the non-fractured side. The authors conclude that if the priority is to avoid open reduction and internal fixation, then the arthrocentesis approach might be a less invasive alternative, albeit with the price of a prolonged healing interval.     

Synovial sarcoma of the mandible

The term synovial sarcoma was first proposed for the histologically well defined entity by Knox in 1936. The name was proposed due to the fact that at least the cases reported in the early part showed some resemblance of the tumour to normal synovial tissue histologically. Thereafter, tumours have been diagnosed from areas without synovial tissue. The diagnosis of monophasic tumours can be difficult and immunostains appear to be a good diagnostic tool in those cases. The occurrence in the mandible is extremely rare. This is a case of synovial sarcoma arising in the condyle involving most of the ramus. The tumour was diagnosed as synovial sarcoma with predominant spindle cell component by correlation of histopathology with immunostains (cytokeratin, epithelial membrane antigen, actin and desmin). The patient has been treated with surgery and radiotherapy.     

X线透视导航下动力髋(髁)螺钉治疗股骨转子间骨折

目的探讨X线透视导航技术在动力髋(髁)螺钉系统治疗股骨转子间骨折中的临床应用。方法应用连接在标准动力髋(髁)器械上的适配器,X线透视导航辅助完成术中松质骨拉力螺钉在股骨颈通道内的入点选择及拉力螺钉的置入。结果8例股骨转子间骨折的应用结果令人满意。手术时间平均为48.8min,X线图像采集平均3.4次。术中和术后无并发症发生。结论肯定了X线透视导航技术在动力髋(髁)螺钉系统治疗股骨转子间骨折中应用的可行性。术中只需1次X线成像就能做出虚拟的手术环境和路径;导航的瞬时追踪功能使术者能实时监测,减少了X线辐射量,缩短了手术时间,提高了拉力螺钉置入的准确度,减小了手术创伤。     

老年股骨髁部骨折的治疗分析

目的探讨治疗老年股骨髁部骨折的内固定器选择及应用要点。方法治疗82例老年股骨髁部骨折,A型26例,B型17例,C型39例。分别采用95°角翼钢板(19例)、T型钢板(5例)、AO股骨髁支持钢板(11例)、动力髁螺钉(dynamiccondylarscrew,DCS)(23例)、股骨髁上带锁髓内钉(greenseligsenhenry,GSH)(24例)进行治疗,共28例采用自体髂骨或同种异体骨植骨。结果经平均14.6个月随访,按Merchan等评分标准评定膝关节功能,总优良率为90.2%。结论老年股骨髁部骨折具有特殊性,针对骨折类型选择内固定器是治疗的重要环节。手术的关键在于保持股骨髁关节面的完整性和牢固固定。     

Safety of, and biological and functional response to, a novel metallic implant for the management of focal full-thickness cartilage defects: Preliminary assessment in an animal model out to 1 year.

Focal full-thickness cartilage lesions of the human medial femoral condyle (MFC) can cause pain and functional impairment. Affected middle-aged patients respond unpredictably to existing treatments and knee arthroplasty may be required, prompting risk of revision. This study assesses the safety of, and biological and functional response to, a metallic resurfacing implant which may delay or obviate the need for traditional arthroplasty. The anatomic contour of the surgically exposed MFC of six adult goats was digitally mapped and an 11 mm diameter full-thickness osteochondral defect was created. An anchor-based Co-Cr resurfacing implant, matching the mapped articular contour, was implanted. Each goat's contralateral unoperated femorotibial joint was used as a control. Postoperative outcome was assessed by lameness examination, radiography, arthroscopy, synoviocentesis, necropsy, and histology up to 26 (n = 3) or 52 (n = 3) weeks. By postoperative week (POW) 4, goats demonstrated normal range of motion, no joint effusion, and only mild lameness in the operated limb. By POW 26 the animals were sound with only occasional very mild lameness. Arthroscopy at POW 14 revealed moderate synovial inflammation and a chondral membrane extending centrally across the implant surface. Radiographs at POWs 14 to 52 implied implant stability in the operated joints, as well as subchondral bone remodeling and mild exostosis formation in the operated and contralateral unoperated joints of some goats. By POW 26, histology revealed new trabecular bone abutting the implant. At POWs 26 and 52 MFC cartilage was metachromatic and intact in the operated and unoperated femorotibial joints. Proximal tibiae of some operated and unoperated limbs demonstrated limited subchondral bone remodeling and foci of articular cartilage fibrillation and thinning. The chondral membrane crossing the prosthesis possessed a metachromatic matrix containing singular and clustered chondrocytes. Our data imply the safety, biocompatibility, and functionality of the implant. Focal articular damage was documented in the operated joints at POWs 26 and 52, but lesions were much reduced over those previously reported in untreated defects. Expanded animal or preclinical human studies are justified.     

下颌骨髁状突骨折的CT诊断

通过对比下颌骨髁状突骨折患者的普通Ｘ线和ＣＴ检查结果，着重提出ＣＴ诊断下颌骨髁状突骨折的方法及重要意义。     

颞下颌关节的三维有限元法研究

本研究利用颞下颌关节ＣＴ扫描资料和计算机图像分析处理技术以及三维有限元方法相结合建立了髁状突的三维有限元模型，结果表明，此方法在技术上是可行的并将有助于颞下颌关节的临床和基础研究。     

Phenotypic switching of in vitro mandibular condylar cartilage during matrix mineralization

In order to analyze the phenotypic conversion of chondrocytes, mandibular condyles of mice and rabbits were cultured under cell and organ culture systems, and then examined by a combination of morphological and biochemical procedures. In organ culture, mandibular condylar cartilage (MCC) obtained from newborn mice began to mineralize from the central zone and then progressively widened towards the peripheral zone. Electron microscopic observations showed that with the increasing duration of the organ culture, chondrocytes at the central zone converted into spindle-shaped osteoblastic cells accompanying the formation of the bone type of thick-banded collagen fibrils. To obtain a better understanding of the chondrocytic conversion, immunolocalizations for type I and type X collagens and osteocalcin (OC) were examined in mouse MCC cells in cell culture. Type X collagen and OC were expressed almost simultaneously at the late stage of culture, and type I collagen was detected along the calcified nodues after the production of these proteins. Northern blot analysis in cell cultures of rabbit MCC indicated that type II collagen and alkaline phosphatase (ALPase) messenger ribonucleic acids (mRNAs) were highly expressed at day 7, but subsequently decreased. In contrast, mRNA for type I collagen was expressed at a low level on day 7 and peaked on day 12. The present results suggest that, morphologically and biochemically, cellular modification in MCC cells under culture conditions occurs at a cellular morphological level and also at marker-gene-expression level.     

下颌骨髁突骨折治疗的临床评价

目的：评价下颌骨髁突骨折的治疗方法,探讨其优缺点。方法：根据X线及临床表现,采取非手术治疗34例,手术治疗8例,42例随访1a以上。结果：治疗效果与患者的年龄,骨折移位程度相关,手术治疗和非手术治疗无明显差异。结论：依据检查指标选择有效的治疗方法,可获得满意疗效。     

带血管蒂髌骨移位修复膝关节面缺损的应用解剖

目的：研究用带血管蒂髌骨移位的方法修复股骨髁和胫髁关节面缺损。方法：用37例经动脉红色乳胶灌注的下肢标本,经解剖、厚切片和铸型研究髌骨的血供。观察30块髌骨和胫骨内外侧髁关节面的形态和面积。结果：供应髌骨的各支动脉在先在髌骨周围吻合成髌周动脉环,再由该环发支进入髌骨;参与形成髌周动脉环的主要动脉有膝上外动脉、膝下外动脉、膝降动上支,膝降动脉髌下支和膝下内动脉;髌骨关节面与股骨内外侧髁下关节面、胫骨内外侧形态大小相似。结论：带血管蒂骨可以移位至股骨内外侧髁、或胫骨内外侧髁,利用髌骨的关节面修复股骨髁或胫骨髁关节面缺损,以期最大限度地保留膝关节的功能。