Osteotomy of the tibial tubercle in complex primary total knee replacement

Objective  Stiffness and severe deformity pose a major challenge in total knee arthroplasty. Numerous techniques have been described to gain exposure and improve knee flexion. Tibial tubercle osteotomy provides excellent and safe exposure of the joint, although mechanical and wound complications have been reported. Materials and methods  We present a series of 32 consecutive complex primary total replacements where an osteotomy of the tibial tubercle was utilised. Results  The patients had a mean follow-up of 2 years and 11 months. Following the procedure, with the exception of one case complicated with deep infection, all of the patients had improved clinically. The mean postoperative range of motion had increased to 102° (give P value < 0.005) and there were no cases of delayed union or non-union. A mechanical complication related to technique occurred in one patient; there were no other cases with a postoperative extension lag. Conclusion  In this challenging population group, we have found a tibial tubercle tuberosity osteotomy to greatly facilitate exposure without compromising the clinical and radiographic outcome.     

28 mm Metasul™ bearings in primary total hip arthroplasty

Assessment of possible low-wear with some former metal-on-metal (MoM) total hip arthroplasties (THA) led to the reintroduction of metallic bearings in the late 80’s. The author reports on two studies of Metasul-28 mm cementless THA. In the first one in a general population, impingement has been the main cause of osteolysis and Co level survey has been a good indicator of Metasul bearing behaviour. In the second study, in a group of 83 less than 50-year-old and active patients, Metasul bearings showed good wear resistance at 7.2 years mean follow-up. In both studies, no general toxic effect could have been detected thus far. According to the current knowledge, it is always reasonable to expect low-wear and better THA longevity with use of MoM bearings under the following conditions: 1) use of a CoCr alloy with high carbide concentration; 2) reduce impingement risk (head without sleeve, slimmer as possible neck, perfectly adapted Morse cone from the same manufacturer, well — oriented components); and 3) prefer cementless acetabular fixation.     

Digital mucoid cyst excision by using the bilobed flap technique and arthroplastic resection

There are a number of proposed causes and treatment approaches for digital mucoid cysts. The described treatment outcomes for this cyst have been variable, with the highest success rate reported with complete excision and single-lobe skin flap closure. This report describes a bilobed flap reconstruction in conjunction with resection of the head of the middle phalanx. A retrospective review was undertaken to evaluate the recurrence rate, complications, and patient satisfaction with this combined procedure. Fifteen patients with an average follow-up of 4.6 years were evaluated. There were no recurrences, flap failures, or other major complications. The use of this flap allows for greater exposure than traditional semi-elliptical incisions while allowing the wide excisional defects to be closed primarily.     

Computerised and technical navigation in total knee-arthroplasty

Abstract The objective of the study was to evaluate the precision, concordance, practicability and the early clinical outcome of the use of a computerised navigation system in a comparative study with a group of 100 patients. Two groups of 50 patients each underwent implantation of a bicondylar knee prosthesis either by means of the freehand navigation system or by means of technical instrumentation. We found that the computerised navigation system provided a higher precision than the technically instrumented implantation: 94% of the prostheses implanted with the navigation system have an alignment within a range of -3° to 3° on of the Mikulicz line. Only 46% of the patients operated by means of the technical instrumentation reached this aspired result. Furthermore, the navigation system showed smaller ranges in the deviation of the aspired alignment. The radiological and computer-modeled alignment values differed both pre- and postoperatively, but to a larger extent before surgery. The varus or valgus deviations of the axis were more distinct radiologically under the weight of the patient’s body than in the computer model. The clinical outcome examined by the use of the HSS score after a mean followup of 7 months is good in both groups, and without significant differences. On average, the duration of surgery was 13 minutes longer in the computerised navigation group. We conclude that the benefit of the computerised navigation system is represented by the high improvement of precision. Achieving early clinical results identical to those in the technical instrumentation group, we expect a reduction of aseptic loosening in the computerised navigation group.     

Trapeziometacarpal joint osteoarthritis: a retrospective study comparing arthrodesis to tendon interposition arthroplasty

Abstract Surgical management of trapeziometacarpal joint osteoarthritis (OA) is still controversial. The aim of this study was to evaluate and compare results of trapeziometacarpal arthrodesis and of tendon interposition arthroplasty. One hundred twenty-six patients suffering from trapeziometacarpal OA underwent surgery between 1996 and 2001. Of these patients, 62 (78 thumbs) treated with joint arthrodesis and 33 (41 thumbs) treated with tendon interposition arthroplasty with abductor pollicis longus (APL) have been evaluated at follow-up and therefore entered this study. Mean age was 53 years, while the mean follow-up was 36 months. Overall results were satisfactory in 84 patients with good pain improvement. Patients treated with arthrodesis showed better functional ability in bi-digital pinch and grip strength. First finger opposition motion, however, was better conserved in patients treated with interposition arthroplasty. Fusions had an 11.5% complication rate (9 thumbs) with nonunions, whereas 14.8% (6 thumbs) of patients treated with interposition arthroplasty developed 1 first metacarpal base collapse, resulting in 1 first ray length reduction. Despite complications, however, patients did not report unsatisfactory results and generally experienced marked pain reduction. This study shows that arthrodesis can be considered the treatment of choice in patients suffering from trapeziometacarpal OA at Eaton stage III or less, whatever the age and when a good pinch strength is needed.     

成人正常股骨解剖测量及其在膝关节置换的临床意义

[目的]为膝关节置换准确截骨和获得良好的下肢力线，对中原地区成人股骨干进行相关测量。[方法]（1）选取47根成人正常股骨标本，拍摄正、侧位数码照片，进行定点、划线、测量五角。（2）实体上确定股骨髓内定位杆进针点的位置：[结果]（1）各角度值反映了股骨远端在冠状位和矢状位的解剖形态。（2）进针点与股骨滑车中心水平距离平均为6．21mm，与后交叉韧带止点前缘距离平均为6．70mm。[结论]（1）股骨远端1／3段与股骨近端1／3段向外侧、前侧成角，且前倾角度大于外翻角度。所以股骨远端在决定股骨髓内定位杆的位置时，冠状面上的力线对位和矢状面上的对位均很重要。（2）全膝关节置换术中确定进针点可参考股骨滑车中心和股骨髁后交叉韧带止点的位置。     

Catastrophic failure of modular Zirconia—Ceramic femoral head components after total hip arthroplasty

Catastrophic failure of two zirconia—ceramic modular femoral heads occurred, despite the theoretical improved toughness of zirconia—ceramic relative to alumina—ceramic. This experience led the authors to return to cobalt—chromium as the metal of choice for articulation against polyethylene in total hip arthroplasty.     

The role of primary total hip replacement for the treatment of the displaced femoral neck fractures

Summary The management of displaced intracapsular fractures of the hip is still controversial because of the high incidence of complications after internal fixation or hemiarthroplasty. To avoid some of these complications we have used primary total hip replacement for independently mobile patients over 65 years of age.Of 49 patients who were interviewed an average of 4.6 years after total hip replacement, 81.6% had excellent or good results as assessed by the Harris Hip Score. At that time two hips had been revised and another converted to Girdlestone due to deep infection. The survival of the prostheses was at 5 years 91.3%.It is concluded that total hip replacement is an established method of management for a selected group of patients with this injury, but further prospective studies are needed in order to define the groups of patients that benefit the most.     

全髋置换术对下肢短缩的治疗

目的：探讨全髋关节置换术对肢体短缩的纠正。方法：2000年2月～2002年12月,将30例接受单侧全髋关节置换术的患进行了研究：男19例,女12例。术前通过临床及对骨盆前后位X线片的测量评估双下肢不等长的程度,然后利用模板预测髋臼及股骨假体的置入位置，估计股骨颈的截骨水平以维持双下肢等长。术中先标记并测量股骨近端至髋臼上方两标记之间的距离，而后在术前估计的位置进行股骨颈截骨。置入假体试模之后再次测量两标记之间的距离和检查髋周软组织的张力、关节活动和drop-kick试验。最后通过调整股骨头假体颈部或头部长度进一步进行纠正。结果：22例肢体短缩2cm以上的病人中。术后双下肢等长(双下肢相差在1cm内)20例，2例仍有短缩，1例短3cm，另1例短1．5cm。8例肢体短缩在1～2cm的病人术后肢体完全等长。全部病人没有髋关节的僵硬和疼痛，活动范围恢复75％以上26例，恢复50％～75％4例。结论：通过术前测量评估，术中定位测量。术中软组织充分松解，置入假体试模后再次测量和检查髋周软组织的张力、关节活动和drop-kick试验,可以有效地治疗下肢的短缩。     

珊瑚型人工髋关节置换术的临床随访及松动原因的分析

自１９８３年至今应用珊瑚型人工髋关节置换术共５４例６０髋。其中人工全髋关节置换术３４例４０髋，人工股骨头置换术２０例２０髋。在５４例６０髋珊瑚型人工髋关节置换术中，有３７髋随访６个月～１３年，平均随访时间约７年，疗效满意率为８５．１％，其中假体松动４例占１４．８％，髋臼松动２例７．４％。假体松动原因是假体与股骨负重界面之间没有达到稳定接触，假体与髓腔形状不相匹配，修整髓腔松质骨时，髓腔扩大器应比假体小一号，避免假体与界面存留缝隙。对于髋臼发育不良的患者应避免髋关节旋转中心向外侧移位，应向内上方加深髋臼以减少水平移位距离，其次髋臼植骨加盖勿在负重区。