Changes in Hip and Knee Muscle Strength in Patients Following Total Hip Arthroplasty

Objective: To investigate changes in hip and knee muscle strength in patients before and after total hip arthroplasty (THA) in comparison with that in healthy adults. Methods: The study included 21 women who underwent unilateral THA (THA group) and 21 age-matched healthy women (healthy group). Maximal isometric strengths of hip flexors, extensors, and abductors, and knee extensors and flexors were measured before surgery and at 4 weeks and 6 months after surgery. Results: Before surgery, muscle strength on both sides, except for hip flexors on the uninvolved side, was significantly lower in the THA group than the corresponding muscle strength in the healthy group. Up to 6 months after THA, strength of all muscle groups on both sides was significantly improved compared with their preoperative status, although the knee extensor strength on the involved side temporarily worsened at 4 weeks. However, the strength of hip extensors and knee extensors on the involved side, and hip abductors on both sides in the THA group remained below that in the healthy group. Conclusions: Our results suggest that rehabilitation specialists should consider increasing the focus on the uninvolved side and encourage patients to continue strength training beyond 6 months after surgery.     

老年人骨质疏松性髋部骨折的治疗初探

目的探讨老年骨质疏松性髋部骨折的临床诊治方法及疗效。方法自2005年4月～2010年3月共治疗70岁以上（70—96岁）骨质疏松性髋部骨折100例,其中男39例,女61例。骨折类型：股骨颈骨折71例,股骨粗隆间骨折29例。其中手术治疗92例,保守治疗8例。其中股骨粗隆间骨折DHS内固定20例,保守治疗8例,人工股骨头置换1例;股骨颈骨折71例人工股骨头置换33例,全髋置换38例。本组患者同时配合抗骨质疏松药物治疗。结果本组所有患者手术顺利进行,术后伤口均一期愈合。本组100例获得随访,随访时间6月～28月,平均14．2月。术后股骨头缺血坏死4例,内固定物松动、滑脱5例、断裂2例,人工股骨头下沉致疼痛5例,脱位2例,精神症状2例。本组病例无肺栓塞、深静脉血栓形成、感染等并发症发生。术后5月,患者均能下地行走,生活自理。平均Harris评分由术前的（45．4±10．7）分恢复到术后1年的（91．5±7．2）分,术后与术前Harris评分比较t=21．1674,P〈0．05。x线片检查示内植物位置良好。结论老年骨质疏松性髋部骨折需要积极的以手术为主的综合治疗。     

Finite element modeling of a generic stemless hip implant design in comparison with conventional hip implants

In this study, the finite element modeling and comparison of the stress and strain analyses were carried out for three different structures that are intact bone, stemless implant and stemmed one. Currently proposed stemless design studied here is the generic concept of stemless implant. This generic stemless implant reconstruction was numerically compared to the conventional stemmed implant and also to the intact bone as control solution. Two loading conditions were applied to the most proximal part of the models, while the most distal part was fixed for all degrees of freedom. The models were divided into two regions and studied along two paths of medial and lateral aspect. The results of this study showed that the stemless implant had less deviation from the control solution of the bone in all regions and in both loading conditions, comparing to the large deviation of the stemmed implant from the intact bone. However, it was shown that the fixation of this type of implant and its effect on sub-trochanter region must be carefully considered for designing the final product of any specific design of stemless implant.     

骨质疏松与老年人髋部骨折的关系

目的探讨老年髋部骨折与髋部骨密度（BMD）和股骨近端几何结构的关系。方法老年髋部骨质疏松骨折47例为骨折组,无骨折50例为对照组,测量两组股骨近端骨密度及股骨颈轴长（FNAL）、颈干角（NSA）（髋部骨折组对其健侧进行检测）,比较分析彼此间的相关性。结果老年髋部骨折组与对照组比较股骨近端骨密度明显降低,FNAL长于对照组,NSA较对照组大。结论股骨近端骨密度和FNAL及NSA可以提高对老年髋部骨质疏松骨折危险性的预测。     

High-resolution ICP–MS determination of Ti,V, Cr,Co, Ni,and Mo in human blood and urine of patients implanted with a hip or knee prosthesis

The main components (Ti, V, Cr, Co, Ni, and Mo) of metallic alloys currently used in hip and knee articular prostheses have been simultaneously determined in human whole blood and urine of implanted people by a (HR)-ICP–MS method previously developed in our laboratory. The determination of those elements has been carried out in patients with knee and hip prosthesis and in a group of pre-operation patients without any metallic device in their bodies, used as controls, demonstrating the usefulness of this technique to perform multielement analysis at ppt levels in complex matrices. The concentrations of V, Cr, Co, Ni, and Mo in urine and blood of implanted people turned out to be very similar to those obtained in control patients. However, raised Ti levels could be found both in urine and blood of patients with articular prostheses made or coated with a titanium alloy (Ti₆Al₄V).     

全髋关节置换术治疗成人先天性髋关节脱位伴骨性关节炎

目的 探讨全髋关节置换术治疗成人先天性髋关节脱位伴骨性关节炎的疗效。方法 2000年6月～2006年3月,对24例（30髋）成人先天性髋关节脱位伴骨性关节炎患者进行了全髋关节置换。其中双侧6例,单侧18例。年龄45～67岁。并对其疗效进行分析,疗效评价根据Harris评分而分为优、良、可、差四级。结果 所有患者手术顺利进行,术后伤口均一期愈合。术后5月,患者均能下地行走,生活自理且恢复日常工作。平均Harris评分由术前的（46．2±8．7）分恢复到术后1年的（90．5±7．4）分,术后与术前Harris评分比较t=17．6714（P〈0．05）,其中评定为优13髋、良14髋、可2髋、差1髋,术后优良率达90．00％。术后髋关节脱位1例。本组病例无肺栓塞、深静脉血栓形成、感染等并发症发生。随访6～49月,X线检查示假体位置良好。结论 全髋关节置换术是治疗成人先天性髋关节脱位伴骨性关节炎的一种有效方法。     

第三代骨水泥技术在人工全髋置换术中的应用

目的探讨第三代骨水泥技术在人工全髋置换术中的临床应用。方法自2000年6月-2006年1月采用第三代骨水泥技术进行全髋关节置换术临床应用37例44髋，并分析其手术时间、总出血量、总输血量、术前与术后Harris评分及术周、术后并发症等。结果所有患者手术顺利进行，手术时间（84．5±6．3min），总出血量（558．4±46．5ml），平均输血量（332．5±21．5m1），术前Harris评分（37．2±12．5），术后Harris评分（90．5±11．5），术后与术前Harris评分比较t=16．541，P〈0．05。术后并发症，脱位1例，精神症状1例。本组病例无肺栓塞、深静脉血栓形成、感染等并发症发生。术后随访6．4～27．2月，平均12．6月，X线检查示假体位置良好。结论第三代骨水泥技术在人工全髋置换术中应用效果令人较为满意。     

股骨近端骨密度结合其几何参数在老年人骨质疏松性髋部骨折诊治中的临床意义

目的探讨股骨近端骨密度与几何结构参数在老年人骨质疏松性髋部骨折诊治中的临床意义。方法将65例髋部骨折患者作为实验组。同期健康体检的60例老年志愿者为对照组。在骨盆片上测量股骨近端几何参数,在股骨颈、Ward’S三角和转子处测量BMD值（髋部骨折组对其健侧进行检测）,对结果进行比较分析。结果实验组的BMD值低于对照组（P〈0．05）;股骨颈骨皮质厚度与股骨颈BMD值有相关性（r=0．54,P〈0．05）;股骨距内侧皮质厚度、转子处BMD值、颈干角和Ward’s三角BMD值相结合在预测髋部骨折中价值较大（r=0．78,r2=0．57,P〈0．05）。结论股骨近端骨密度结合其几何结构参数在骨质疏松性髋部骨折的诊治中具有较大的临床意义。     

全髋关节置换术后并发症分析及处理

目的 探讨髋关节人工假体置换术后并发症产生的原因及防治措施。方法回顾调查1995年1月～2002年12月我院进行人工全髋关节置换术246例（255髋）。股骨颈骨折109例，股骨头缺血坏死78例，骨关节病45例，强直性脊柱炎5例，股骨上段肿瘤9例。结果246例（255髋）患者其中7例已死亡，失访8例，其余231例（235髋）患者随访2．0～9．0年，平均5．5年：发现术后并发症46例，髋关节脱位6例，伤口感染4例，假体松动下沉6例，下肢静脉怆塞3例，股骨骨折1例，疼痛26例。结论合理选择人工假体，术中严格操作，术后加强护理，可降低人工假体置换术后并发症的发生率。     

Ion Implantation on Ultra High Molecular Weight Polyethylene (Uhmwpe) for Medical Prosthesis

In order to improve the wear resistance of ultra high molecular weight polyethylene (UHMWPE), a surface modification is induced by ion implantation of different ions at 300 keV energy with doses ranging between 10¹⁴ -10¹⁷ ions/cm². Wear measurements, in terms of weight loss, are performed with a “pin on disc” friction machine; these tests measure the wear properly of the UHMWPE against a metallic probe before and after the ion implantation treatment. Results demonstrate that in the implanted samples the wear resistance increases by about 76% with respect to the non-irradiated samples. The irradiated polymeric layer was characterized with the mass quadrupole spectrometry, Raman spectroscopy, infrared absorption analysis, scanning electron microscopy, atomic force microscopy and calorimetric analysis. The results suggest that wear decrease effect can be attributed to the ion bombardment inducing a high carbon surface concentration and cross-linking effects in the irradiated polymeric layer. The irradiated UHMWPE surfaces find special applications in the field of the mobile prosthesis such as hip joints.