Arthroscopic loose-body removal in posterior compartment of the knee joint: a technical note

The arthroscopic removal of loose bodies in the knee joints is a relatively common procedure. Quite often intra-articular loose bodies tend to localize at the posterior compartment due to gravity effect. However, it is often technically demanding to find and remove loose bodies located at the posterior compartment of the knee joint arthroscopically. We present the technical aspects of arthroscopic removal of the loose bodies located in the posterior compartment of the knee joint. Loose bodies at posterior compartment were subdivided into six regions in posterior knee compartment with preoperative MRI and arthroscopic findings. Each section needs slight different application of arthroscopic techniques for removal. We retrospectively studied 52 knees in 50 patients who underwent arthroscopic loose-body removal in posterior compartment, in 28 knees, additional posterior trans-septal portal was needed for removal of loose bodies. With the help of trans-septal portal, we have successfully removed the loose bodies even from the most difficult locations in posterior compartment.     

An <Emphasis Type="Italic">en bloc</Emphasis> avulsion fracture of tibial tuberosity and Gerdy’s tubercle in an adolescent basketball player: a case report

We report a case of en bloc avulsion fracture of tibial tuberosity and Gerdy’s tubercle, which has never been reported. A 14-year-old boy suffered from an acute pain in his left knee during running just before a jump. Simple radiographs showed an avulsion of the tibial tuberosity. On CT scans, the fractured fragment was attached not only to patellar tendon but also to iliotibial band (ITB) via Gerdy’s tubercle. MRI evaluation revealed no intra-articular associated pathology. Open reduction and internal fixation with three cannulated screws were performed under lateral parapatellar approach to expose both the tibial tuberosity with patellar tendon and Gerdy’s tubercle with ITB. At postoperative 1 year, he could walk, run, squat, and complained of no difficulty in activities on daily living with full range-of-motion of the knee. Radiographs showed well-healed fracture in situ. Gradually, he returned to sports activity. We believe that the injury was caused by the dynamic pull of quadriceps muscle via patellar tendon onto tibial tuberosity and the mostly static pull of ITB onto Gerdy’s tubercle, both of which took a part in the fracture of the anterolateral portion of the unfused epiphysis of proximal tibia. The pes anserinus attaching on the anteromedial metaphysis of proximal tibia might exert the opposing deforming force. Preoperative planning including the determination of the extent of fracture and recognition of concomitant injury is a prerequisite for appropriate treatment.     

How to make a machine think in art psychotherapy: An expert system's reasoning process

In making decisions, a human being considers all of the factors concerning the situation in a comprehensive and intuitive manner by using all of his or her experience and knowledge. Due to the inherent nature of human decision making, the reasoning process from confronting the problem to finding a solution is too complicated to be explicitly represented. In this paper, we implement an expert system for the diagnosis process of art psychotherapists. We model the complicated mechanism of this process as several procedural stages and feedbacks. We devise a suitable method of maintaining consistency among numerous decisions derived from the system. We also provide the system with a learning facility to improve its intelligence. Finally, we demonstrate the usefulness and suitability of the proposed system through a case study.     

应用双极人工股骨头和骨移植进行髋臼假体翻修术

目的分析双极人工股骨头和嵌压植骨联合应用对合并巨大骨缺损的髋臼侧假体进行翻修术的临床疗效.方法 1988年3月～2000年11月期间利用双极人工股骨头对合并巨大骨缺损的23例24髋进行髋臼侧假体翻修术.其中男15例,女8例,平均年龄48岁,平均随访6.4年.翻修术的原因中假体松动21髋,骨溶解2髋,感染1髋.髋臼骨缺损根据AAOS分类,Ⅰ型3髋,Ⅱ型6髋,Ⅲ型15髋.自体骨移植2髋,异体骨移植8髋,混合移植14髋.临床评价采用Harris评分,并在X线片上对髋臼假体的移位、移植骨的愈合与吸收、髋臼形态的塑形以及再次翻修等进行分析.结果 Harris评分术前为49分,术后1年为78分,最后随访时间为76分.髋臼假体向上内方向移位19髋,向上外方向移位5髋.并发症中异位骨化12髋,感染1髋,复发性脱位1髋.因感染和髋臼假体严重移位采用非骨水泥型髋臼假体行再次翻修术2髋.结论双极人工股骨头和嵌压植骨联合应用对合并巨大骨缺损的髋臼侧假体进行翻修术具有髋臼形态塑形良好、移植骨愈合率高以及髋臼假体不需要坚强内固定等优点,可作为一种特殊情况下的髋臼侧假体翻修术;其缺点是髋臼假体移位.     

Mutations of beta-catenin and AXIN I genes are a late event in human hepatocellular carcinogenesis.

BACKGROUND: Hepatocellular carcinoma (HCC) is a well-known cancer involving the Wnt pathway in its carcinogenesis. AIMS: However, it is not clear whether these genetic changes are early genetic events in hepatocarcinogenesis or not. METHOD: In this study, we performed mutational analysis of the beta-catenin and AXIN I genes, and immunohistochemistry for beta-catenin in a series of 114 hepatocellular nodular lesions, including premalignant lesions such as low-grade dysplastic nodules (LGDNs) and high-grade dysplastic nodules (HGDNs). RESULTS: In the present study, mutations of the beta-catenin and AXIN I genes were detected in 16% (13 out of 81) and 6.2% (five of 81) of the HCCs, respectively. However, no mutations were found in 14 LGDNs and 19 HGDNs. Moreover, abnormal nuclear beta-catenin immunostaining was observed in 30 of 81 HCCs, but not in dysplastic nodules. CONCLUSION: Taken together, our data suggest that beta-catenin stabilization because of either beta-catenin or AXIN I mutation might be a late event for malignant progression rather than an early genetic event involving the initiation of HCC development.     

A case of strangulated small bowel obstruction caused by Meckel's diverticulum in an adult

Meckel's diverticulum results from incomplete closure of the omphalomesenteric duct, and is the most common congenital anomaly of the small intestine. We present a case report of a 42-year-old patient who developed a strangulated intestinal obstruction as a complication of Meckel's diverticulum. The strangulated bowel obstruction was suggested by contrast-enhanced computed tomography. He recovered after a diverticulectomy and had no need for a small bowel resection.     

Acute renal infarction: a 10-year experience

The diagnosis of acute renal infarction (ARI) is often delayed or unrecognised because of its non-specific presentation and the rarity of the disease. We evaluated the clinical presentations, laboratory findings, underlying medical conditions and treatment of 18 Chinese patients with ARI who presented to the emergency department (ED) of a tertiary teaching hospital from 1995 to 2004. We identified 14 non-trauma and four trauma patients with ARI. The mean duration from the onset of symptoms to the diagnosis of ARI was 1.9 days. The prevalence of concurrent events was 39%. About 64.5% of non-trauma patients had histories of atrial fibrillation, structural heart diseases or previous embolic events. The laboratory characteristics were neither specific nor sensitive for the diagnosis of ARI. Conservative treatment, local intra-arterial thrombolytic and i.v. thrombolytic therapies were provided in nine, five and two patients respectively. Decreased effective renal plasma flow in affected kidneys was found in three of three patients. Serum creatinine (Cr) was normal or elevated not more than 25% of baseline in 16 cases. ARI may resemble many non-renal diseases; however, repeated evaluation and a high index of suspicion are required for early diagnosis. Concurrent injuries or thromboembolism in other foci should be noticed. Early contrast-enhanced computerized tomography scan should be considered for high-risk patients. Patients with ARI should be followed by functional studies rather than serum Cr level.     

Claudin-7 is highly expressed in chromophobe renal cell carcinoma and renal oncocytoma

Claudin-7 has recently been suggested to be a distal nephron marker. We tested the possibility that expression of claudin-7 could be used as a marker of renal tumors originating from the distal nephron. We examined the immunohistochemical expression of claudin-7 and parvalbumin in 239 renal tumors, including 179 clear cell renal cell carcinoma (RCC)s, 29 papillary RCCs, 20 chromophobe RCCs, and 11 renal oncocytomas. In addition, the methylation specific-PCR (MSP) of claudin-7 was performed. Claudin-7 and parvalbumin immunostains were positive in 3.4%, 7.8% of clear cell RCCs, 34.5%, 31.0% of papillary RCCs, 95.0%, 80.0% of chromophobe RCCs, and 72.7%, 81.8% of renal oncocytomas, respectively. The sensitivity and specificity of claudin-7 in diagnosing chromophobe RCC among subtypes of RCC were 95.0% and 92.3%. Those of parvalbumin were 80.0% and 88.9%. The expression pattern of claudin-7 was mostly diffuse in chromophobe RCC and was either focal or diffuse in oncocytoma. All of the cases examined in the MSP revealed the presence of unmethylated promoter of claudin-7 without regard to claudin-7 immunoreactivity. Hypermethylation of the promoter might not be the underlying mechanism for loss of its expression in RCC. Claudin-7 can be used as a useful diagnostic marker in diagnosing chromophobe RCC and oncocytoma.