Computer-assisted fluoroscopic navigation system for removal of distal femoral bone cement in revision total hip arthroplasty

Removal of the femoral bone cement in revision total hip arthroplasty with a high-powered drill or burr potentially has a risk of damage to the bone, resulting in perforation and fracture of the femur. Recently, we have used a computer-assisted fluoroscopic navigation system for the revision of cemented total hip arthroplasty with a high-powered burr and completely removed the distal femoral bone cement with no complications in 6 cases. Thus, a computer-assisted fluoroscopic navigation system is a useful tool for the improvement of the surgical technique in revision total hip arthroplasty.     

Resurfacing arthroplasty of the hip in osteopetrosis

A 34-year-old woman with a benign form of osteopetrosis developed osteoarthritis of the hip. In order to avoid the difficulties associated with inserting the femoral component of a conventional total hip arthroplasty, a hybrid metal-on-metal resurfacing was performed. There were several technical challenges associated with the procedure, including the sizing of the component, press-fit fixation of the acetabular component and femoral head preparation, as well as trying to avoid a fracture. No surgical complication occurred. After more than a year following surgery, the patient showed excellent clinical function and remained satisfied with the outcome. We conclude that the hybrid metal-on-metal resurfacing arthroplasty represents a valuable option for the treatment of patients with osteopetrosis and secondary hip osteoarthritis.     

Case report: A 10 years follow-up of periprosthetic femoral fracture after total hip arthroplasty in osteopetrosis

Osteopetrosis is an inherited disorder characterized by increased bone density and brittle bone quality. Degenerative changes often occur after the age of 40 in patients with osteopetrosis. Operative intervention is the primary treatment option if the clinical manifestation of secondary osteoarthritis is severe. A 44-year-old male suffering autosomal dominant osteopetrosis and progressive unilateral hip osteoarthritis required a total hip arthroplasty. However, there were several technical challenges associated with this procedure including creating a femoral medullary canal and developing a Vancouver type B2 periprosthetic femoral fracture postoperatively. To afford some experience for the management of similar cases, we here present our technical solutions to these problems.     

Long-term outcome of cemented total hip arthroplasty with the Charnley-type femoral stem made of titanium alloy

BackgroundTotal hip arthroplasty is a successful treatment for hip diseases including osteoarthritis, osteonecrosis of the femoral head, and rheumatoid arthritis. Various designs of cemented femoral stems made of stainless steel and titanium alloy have been used. Among them, Charnley-type femoral stems made of stainless steel have often been reported to have good long-term outcome. However, the long-term outcome of the Charnley-type femoral stem made of Ti alloy is yet to be reported. We conducted a retrospective study to assess the long-term outcome of cemented primary total hip arthroplasty with the Charnley-type femoral stem made of Ti alloy.MethodsBetween October 1988 and February 1997, 341 cemented primary total hip arthroplasties with the Charnley-type femoral stem made of Ti alloy were consecutively performed in our hospital. Among these, 164 patients (211 hips) who underwent this procedure were followed up for more than 12 years, and the surgical hips were analysed clinically and radiologically. The mean follow-up period was 20.6 years. Kaplan–Meier survival analyses were performed to assess femoral component survival. Factors affecting stem revision for aseptic loosening were also investigated using log-rank tests.ResultsIn the functional assessment, the preoperative Japanese Orthopaedic Association score significantly improved from 47.2 points preoperatively to 79.0 points at the final follow-up. Eventually, 33 femoral stems were revised, of which 12 were revised for aseptic loosening. In the Kaplan–Meier survival analysis, the 20-year survival rates with stem revision for aseptic loosening and radiological stem loosening at the end points were 95.9% and 97.1%, respectively. Original diagnosis (non-osteoarthritis) was the only significant factor for aseptic loosening of the femoral stem.ConclusionsCemented primary total hip arthroplasty with the Charnley-type femoral stem made of Ti alloy showed excellent outcomes for more than 20 years.     

应用S-ROM全髋关节置换术治疗Crowe Ⅳ型髋臼发育不良

目的总结采用粗隆下截骨和生物固定型带股骨柄模块的人工关节假体治疗CroweⅣ型髋臼发育不良伴骨关节炎的效果及经验。方法回顾从2004年2月到2009年4月对12例21髋CroweⅣ型髋臼发育不良伴骨关节炎患者治疗的详细过程及疗效,记录所有的并发症。全部采用粗隆下截骨和S-ROM生物固定型人工关节假体置换术进行治疗。髋臼杯假体均植入真臼位置,7例13髋采用自体股骨头于髋臼外上方作结构性植骨,均作了粗隆下缩短截骨术,平均截骨长度为39.4 mm(35~50 mm)。结果平均随访30.8个月(6~62个月)。髋关节Harris评分明显改善(t=24.862,P0.01),从术前的平均(38.2±6.4)分(28~48分)到术后平均(82.1±8.6)分(62~94分)。术后肢体均得到不同程度的延长(t=12.099,P0.01),平均(33.5±12.7)mm(11~65 mm)。术前所有患者均有明显跛行,术后4例有轻度跛行,2例仍需扶双拐行走。19髋股骨截骨处愈合良好,2髋截骨处延迟愈合。在最后一次回访时显示髋臼假体和股骨柄假体位置均良好,无松动、下沉、断钉、骨溶解及异位骨化出现。髋关节中心平均下移了73.0 mm(46~105 mm)。结论利用S-ROM带股骨柄模块的生物固定型人工关节假体的高度适配性,加上在真臼位置加深髋臼,适当植骨,以及精确的粗隆下截骨,是治疗CroweⅣ型髋臼发育不良伴骨关节炎的良好选择。     

Outcomes of total hip arthroplasty are similar for patients with displaced femoral neck fractures and osteoarthritis

This study attempted to evaluate whether total hip arthroplasty for displaced femoral neck fractures had significantly different outcomes when compared with total hip arthroplasty for osteoarthritis. This is a retrospective study of 60 patients who had total hip arthroplasties between 1997 and 2001. Thirty patients (mean age, 79.7 years) had total hip arthroplasties for displaced femoral neck fractures; 30 patients (mean age, 76.9 years) were treated with total hip arthroplasties for osteoarthritis. The same surgeon used the modified lateral approach for all surgeries. All patients had radiographic assessment, physical examination, and evaluation with the Harris hip score. The mean followup was 38 months. The mean Harris hip score for the 25 patients treated with a total hip arthroplasty for a femoral neck fracture was 81 points; the mean hip score for the 27 patients treated with a total hip arthroplasty for osteoarthritis was 87 points. No statistically significant differences between these groups were observed. Patients who were treated with a total hip arthroplasty for a femoral neck fracture did not have increased perioperative morbidity compared with patients who had a total hip arthroplasty for osteoarthritis. This study suggests that the outcomes for total hip arthroplasties in this consecutive series of patients treated for displaced femoral neck fractures and osteoarthritis are comparable.     

Computer-assisted guidewire insertion for hip fracture fixation

OBJECTIVE:: This study was designed to test in a laboratory setting a novel computer-assisted fluoroscopic technique and a conventional fluoroscopic technique for open reduction and internal fixation (ORIF) of hip fractures. Our hypothesis is that a novel computer-assisted fluoroscopic technique will achieve acceptable guidewire placement in one pass, with decreased fluoroscopic time and with accuracy and precision better than conventional technique. DESIGN: Prospective, randomized trials. SETTING: Laboratory. PARTICIPANTS: Thirty, Sawbone, femur phantoms. INTERVENTION: Dynamic hip screw guidewires were inserted into 15 femur phantoms under fluoroscopic guidance by using computer-assisted fluoroscopic ORIF technique, and 15 femurs were inserted by using a conventional fluoroscopic-assisted ORIF technique. MAIN OUTCOME MEASUREMENTS: Ideal guidewire placement was defined as the center of the femoral head, 5 mm from the apical bone edge on anteroposterior and lateral views. Accuracy was measured as distance to ideal placement, and the number of passes and fluoroscopic time were noted for each trial. RESULTS: The computer-assisted technique achieved an average guidewire placement that was as accurate as the conventional technique in fewer passes, 1.1 +/- 0.2 (mean +/- standard deviation) compared with 2.4 +/- 1.1 (P < 0.0001), respectively, and with fewer fluoroscopic images, 2 +/- 0 compared with 13.5 +/- 3 (P < 0.0002), respectively. Guidewire placement in both groups was within the tip-apex distance defined by Baumgaertner et al. CONCLUSIONS: The computer-assisted technique was significantly more accurate and precise than conventional technique. It also required fewer drill tracks through the femur and exposed the patient and the surgical team to significantly less ionizing radiation.     

Computer-assisted two-dimensional preoperative planning for total hip arthroplasty: clinical evaluation

The purpose of this study is to clinically validate a new two-dimensional preoperative planning software for cementless total hip arthroplasty (THA). Manual and two-dimensional computer-assisted planning were compared by an independent observer for each of the 30 patients with osteoarthritis who underwent THA. This study showed that there were no statistical differences between the results of both preoperative plans in terms of stem size and neck length (<1 size) and hip rotation center position (<5 mm). Two-dimensional computer-assisted preoperative planning provided successful results comparable to those using the manual procedure, thereby allowing the surgeon to simulate various stem designs easily.     

Total Hip Arthroplasty in Patients With Osteopetrosis

BackgroundOsteopetrosis is an inherited bone disease associated with high risk of osteoarthritis and fracture non-union, which can lead to total hip arthroplasty (THA). Bone quality and morphology are altered in these patients, and there are limited data on results of THA in these patients. The goals of this study were to describe implant survivorship, clinical outcomes, radiographic results, and complications in patients with osteopetrosis undergoing primary THA.MethodsWe identified 7 patients (9 hips) with osteopetrosis who underwent primary THA between 1970 and 2017 utilizing our total joint registry. The mean age at index THA was 48 years and included two males and five females. The mean follow-up was 8 years.ResultsThe 10-year survivorship free from any revision or implant removal was 89%, with 1 revision and 1 resection arthroplasty secondary to periprosthetic femoral fractures. The 10-year survivorship free from any reoperation was 42%, with 4 additional reoperations (2 ORIFs for periprosthetic femoral fractures, 1 sciatic nerve palsy lysis of adhesions, 1 hematoma evacuation). Harris hip scores significantly increased at 5 years (P = .04). Five hips had an intraoperative acetabular fracture, and 1 had an intraoperative femur fracture. All postoperative femoral fractures occurred in patients with intramedullary diameter less than 5 mm at a level 10 cm distal to the lesser trochanter.ConclusionPrimary THA in patients with osteopetrosis is associated with good 10-year implant survivorship (89%), but a very high reoperation (58%) and periprosthetic femoral fracture rate (44%). Femoral fractures appear associated with smaller intramedullary diameters.     

In vivo comparison of hip separation after metal-on-metal or metal-on-polyethylene total hip arthroplasty

BACKGROUND: Twenty subjects were analyzed in vivo with use of video fluoroscopy to determine if the femoral head separates from the acetabular component during normal gait and to determine if the amount of separation differs between metal-on-metal and metal-on-polyethylene total hip prostheses. METHODS: Ten subjects had been treated with a metal-on-metal total hip arthroplasty and ten, with a metal-on-polyethylene total hip arthroplasty. All of the prostheses were implanted by the same surgeon utilizing the same surgical technique, and all were judged to be clinically successful (a Harris hip score of >90 points). Each subject walked with a normal gait on a level treadmill while under fluoroscopic surveillance. The two-dimensional fluoroscopic videotapes were then converted into three-dimensional images with use of a computer-automated model-fitting technique. Each implant was analyzed at various flexion angles to assess the amount of femoral head sliding. RESULTS: No femoral head sliding was observed in the subjects with a metal-on-metal implant, whereas all ten subjects with a metal-on-polyethylene implant had sliding that was greater than our threshold value of 0.75 mm. The average amount of femoral head sliding in these subjects was 2.0 mm, and the sliding was observed during the swing phase of gait. The sliding was typically seen medially while the femoral head remained in contact with the acetabular component superolaterally. CONCLUSIONS: Femoral head sliding commonly occurred following traditional metal-on-polyethylene total hip arthroplasty but not after metal-on-metal arthroplasty. These kinematic data may be of value in future hip-simulation studies to better duplicate wear patterns observed in retrieval analyses, assist in the understanding of the lubrication and wear rates of metal-on-metal designs, and facilitate designing of prosthetic components that minimize wear and optimize hip kinematics.     

Total joint arthroplasty in patients with osteopetrosis: a report of 5 cases and review of the literature

Osteopetrosis, an inherited disorder of bone metabolism, is associated with multiple musculoskeletal complications. Two of these problems, osteoarthritis and periarticular nonunions, may be considered for treatment with total joint arthroplasty. However, there is little information on the early and longer-term results, complications, and technical difficulties related to performing arthroplasty in patients with osteopetrosis. We report the results of 3 total hip arthroplasties and 2 total knee arthroplasties in patients with osteopetrosis. These cases in combination with a literature review provide further insight into results, complications, and technical challenges of performing total joint arthroplasty in patients with osteopetrosis.     

Uncemented total hip arthroplasty with subtrochanteric derotational osteotomy for severe femoral anteversion.

Total hip joint arthroplasty (THA) in the presence of severe femoral anteversion (>50 degrees) is technically demanding. This problem is often encountered in patients with osteoarthritis secondary to hip joint dysplasia or congenital dislocation. We describe a method of THA in which an uncemented femoral prosthesis is used in conjunction with subtrochanteric derotational osteotomy. This technique allows the restoration of the normal proximal femoral anatomy, including the abductor muscle lever arm without resorting to greater trochanteric transfer. Correction of the excessive femoral anteversion avoids the tendency for postoperative anterior instability. The osteotomy site may also serve as the site for femoral shortening or angular correction when required, which preserves the normal femoral flare. The prostheses used were custom CAD/CAM (computer-assisted design/computer-assisted manufacturer) in design and had the following features: a close intramedullary proximal fit, with collar, lateral flare, and hydroxyapatite coating to achieve early proximal fixation, and longitudinally cutting fluted stem to provide immediate rotational stability across the osteotomy site. Although we used CAD/CAM custom prostheses, off-the-shelf uncemented hip prostheses with similar design features have become available. We report on 7 patients who underwent THA using this technique. The average patient age was 49 years (range, 34-61 years) with a mean follow-up period of 31 months (range, 16-60 months). To date, all cases have had a satisfactory outcome with evidence of union at the osteotomy site. Harris hip scores improved from an average of 44 preoperatively to 91 by the end of follow-up period. One case was complicated by delayed union at the osteotomy site, which was successfully corrected with bone grafting and temporary plate stabilization.     

Contemporary total hip arthroplasty with and without cement in patients with osteonecrosis of the femoral head

BACKGROUND: The rate of failure of primary total hip arthroplasty in patients with osteonecrosis of the femoral head is higher than that in patients with osteoarthritis. The purpose of this prospective study was to document the clinical and radiographic results of arthroplasty with so-called third-generation cementing and the results of second-generation cementless total hip arthroplasty in ninety-eight consecutive patients with osteonecrosis of the femoral head. METHODS: Fifty patients who had had simultaneous bilateral total hip arthroplasty with a cemented stem in one hip and a cementless stem in the other and forty-eight patients who had had a unilateral total hip arthroplasty with a cementless stem were included in the study. A cementless acetabular component was used in all hips. The presumed cause of the osteonecrosis was ethanol abuse in fifty-seven patients, unknown in twenty-seven, fracture of the femoral neck in nine, and steroid use in five. There were eighty men and eighteen women. The mean age at the time of the arthroplasty was 47.3 years (range, twenty-six to fifty-eight years). Clinical and radiographic evaluations were performed preoperatively; at six weeks; at three, six, and twelve months; and yearly thereafter. The average duration of follow-up was 9.3 years. RESULTS: The average Harris hip scores in the group treated with unilateral arthroplasty (97 points) and the group treated with bilateral arthroplasty (94 points) were similar at the time of final follow-up. They were also similar between the group treated with cement (mean, 96 points) and that treated without cement (95 points). No component had aseptic loosening in either group. In one hip, a cemented femoral stem (2%) and a cementless cup were revised because of infection. Two cementless stems (2%) were revised because of fracture of the proximal part of the femur with loosening of the stem. Annual wear of the polyethylene liner averaged 0.22 mm in the group treated with cement (a zirconia head) and 0.14 mm in the group treated without cement (a cobalt-chromium head). The prevalence of osteolysis in zones 1 and 7 of the femur was 16% in the group treated with cement and 24% in the group treated without cement. CONCLUSIONS: Advancements in surgical technique and better designs have greatly improved the long-term survival of cemented and cementless implants in young patients with osteonecrosis of the femoral head. Although there was no aseptic loosening of the components, a high rate of linear wear of the polyethylene liner and a high rate of osteolysis in these high-risk young patients remain challenging problems.     

计算机导航系统辅助下全髋关节表面置换的初步经验

目的 初步评估计算机辅助下行全髋关节表面置换的手术方法及假体植入的精确性.方法 对40例患者分成导航组(20例)和对照组(20例),分别采用计算机导航系统辅助和标准常规技术完成全髋关节表面置换术.比较两组手术时间、术中失血量、Harris髋关节评分(HHS),以及髋臼杯外展角和前倾角的偏移度及股骨假体柄干角和前倾角的偏移度.结果 手术时间导航组较对照组长38.7min(P＜0.05),术中平均出血量导航组较对照组多109.4 ml(P＜0.05).随访平均14.5个月,HHS评分两组比较差异无统计学意义(P＞0.05).对照组髋臼杯外展角偏移度(7.3°±4.3°)大于导航组(1.9°±1.3°)(P＜0.05),对照组髋臼杯前倾角偏移度(3.9°±2.3°)大于导航组(2.4°±1.5°)(P＜0.05).导航组股骨假体柄干角偏移度(1.5°±1.0°)小于对照组(11.3°±1.3°)(P＜0.05),导航组股骨假体前倾角偏移度(1.8°±2.3°)小于对照组(6.5°±5.3°)(P＜0.05).结论 计算机导航系统辅助下行全髋关节表面置换术可以提高假体植入的精确性,避免股骨颈皮质骨切迹,降低股骨颈骨折的风险.     

Life expectancy after total hip arthroplasty.

The 6-year survival rate was investigated in 646 patients undergoing total hip arthroplasty for osteoarthritis, rheumatoid arthritis, or complications following femoral neck fracture between 1978 and 1982. A comparison of mortality was done between patients treated by osteosynthesis for fresh femoral neck fracture and a matched general population. The mortality was lower than that of the matched general population after total hip arthroplasty and even lower for patients treated for fresh femoral neck fracture. Patients undergoing total hip arthroplasty for osteoarthritis had the highest survival rate, followed by patients with rheumatoid arthritis and complications after femoral neck fractures.     

Cemented total hip arthroplasty: still relevant in the new millennium?

Total hip arthroplasty can be performed successfully using cement or cementless technology. Cemented femoral stems can achieve enduring long-term suvivorship as long as meticulous surgical technique is utilized and patient selection is appropriate. Cemented acetabular components should only be utilized in patients with less than 10 years of remaining life expectancy. Critical risk factors for cemented total hip arthroplasty include atrophic osteoarthrtis on the acetabular side and unfavorable femoral geometry for the femoral stem such as "the stove-pipe" canal. Rapid polyethylene wear and osteolysis are rarely seen in contemporary cemented total hip arthroplasty performed with a smooth, tapered, collarless femoral stem with a highly polished head and a well-designed acetabular component.     

髋关节置换术中股骨假体周围骨折危险因素的分析

目的分析髋关节置换术中股骨假体周围骨折的发生情况和危险因素。方法选择本组自2002年1月至2008年12月所有行初次和翻修髋关节置换术患者共3021髋(初次置换术2718髋,翻修术294髋),分析术中股骨假体周围骨折的发生情况,并用Logistic回归分析骨折发生的相关因素,包括性别、年龄、术前诊断、假体类型、固定方式。用2检验进行初次置换和翻修术中发生骨折的差异性检验。结果总的术中股骨假体周围骨折发生率为5.7%(173/3021),其中初次置换发生率为4.0%(110/2718),翻修术发生率为21.4%(63/294)。初次置换应用骨水泥股骨假体术中骨折发生率为1.9%(8/429),非骨水泥股骨假体术中骨折发生率为4.5%(102/2289),初次置换术中骨折82.7%(91/110)发生于干骺端;翻修术应用骨水泥股骨假体术中骨折发生率为18.8%(21/112),非骨水泥股骨假体术中骨折发生率为23.1%(42/182),翻修术术中骨折62%(39/63)发生于骨干部。Logistic回归分析显示:初次髋关节置换术中骨折的危险因素包括性别、术前诊断、固定方式、假体类型;翻修术性别、年龄、假体固定方式不是引起术中骨折的危险因素。应用2检验,翻修术中股骨假体骨折的风险与初次置换相比差异有统计学意义(P0.000),OR值为6.5,95%CI(4.6,9.1)。结论初次髋关节置换术中股骨假体周围骨折的发生率为4.0%,主要发生于干骺端(83.6%),女性、髋关节发育不良、髋部骨折、高位脱位、非骨水泥固定是术中骨折的危险因素;髋关节翻修术中股骨假体周围骨折的发生率(21.4%),远高于初次髋关节置换术,主要发生于骨干部(61.9%),骨折的发生与否可能主要取决于翻修时的骨质情况,性别、年龄、假体固定方式并不是主要的影响因素。     

Total hip arthroplasty in the treatment of arthrosis with coexistent high developmental hip dislocation

The question if total hip arthroplasty ought to be advised for patients with high developmental hip dislocation is still actual. The subject of hip arthroplasty, as a method of surgical treatment of high developmental hip dislocation, was analyzed on the base of follow up of seven patients, who underwent this procedure. The mean age of patients was 44.5 (+/- 12.6) years. The mean time of follow up was 64.4 (21.6) months. Initial three patients were treated in two stage regime. In first stage, a surgical hip liberalization and skeletal traction through 3 weeks was performed. In 2nd stage we did total hip replacement with simultaneous shortening of the femoral shaft just below the lesser trochanter. In next four patients we performed total hip arthroplasty with simultaneous shortening of the femoral shaft in one stage. Protection of undesirable rotational instability after osteotomy was done by means of different ways of osteotomy fixation describe in paper. Applied surgical treatment allowed for implanting a cup of prosthesis in original place of acetabulum and reduction of the big anteversion of the femoral neck. The hip congruency was improved in all patients. Score in functional Harris hip scale increased from mean value of 50 points before hip arthroplasty to mean value of 85 points after surgery. The symptoms of late consolidation of osteotomy were observed in one patient with transverse osteotomy without anty-rotational fixation. Total hip replacement with simultaneous "Z" shortening osteotomy of the femoral shaft give good such clinical as radiological results in the treatment of hip osteoarthritis in accordance to high developmental hip dislocation.     

Removal of a well-fixed femoral stem: Tour de force

Revision total hip arthroplasty often requires removal of a well-fixed femoral implant. Ease of implant removal is dependent on the stem design, geometry, and location/extent of porous ingrowth surface. In an effort to preserve the proximal femoral bone, many different surgical exposures and techniques are available. The intent of this review article is to briefly review the most popular techniques and their indications for use revision total hip, well-fixed femoral stem, femoral stem design.     

Osteoarthritis associated with osteopetrosis treated by total knee arthroplasty. Report of a case

Osteopetrosis is due to a defect in osteoclastic cell function and results in osteosclerosis and progressive obliteration of the marrow spaces. Early onset osteoarthritis is associated with osteopetrosis. The authors describe a case of early onset osteoarthritis associated with osteopetrosis treated by total knee arthroplasty. The marblelike quality of osteopetrotic bone makes surgical treatment of these patients technically challenging and requires modification of standard surgical technique.