The NexGen LPS-flex to the knee prosthesis at a minimum of three years

We carried out a prospective study to assess the clinical outcome, complications and survival of the NexGen Legacy posterior-stabilised-Flex total knee replacement (TKR) in a consecutive series of 278 knees between May 2003 and February 2005. Mean follow-up for 259 TKRs (98.2%) was 3.8 years (3.0 to 4.8). Annual follow-up showed improvement in the Knee Society scores (paired t-test, p < 0.05). At the last follow-up, the mean maximum flexion was 135 degrees (110 degrees to 150 degrees). Two knees showed radiolucent lines, but revision was not required because the patients were asymptomatic. Revision was required in one case because of infection, but there were no prosthesis-related revisions. There were no other complications. The estimated survival rate at four years with revision for any reason and prosthesis-related problems was 99.6% and 100%, respectively. This relatively large study indicates that the legacy posterior stabilised-Flex design provides excellent short-term outcome but warrants ongoing evaluation to confirm the long-term durability and functioning of the implant.     

Acetabular reconstruction with a bipolar prosthesis. Five year results of the Dautry technique

We report the results of acetabular reconstruction using a bipolar prosthesis bearing on cancellous bone graft in 37 patients after a minimum of five years. There was a satisfactory clinical outcome in 58% when assessed by pain, range of movement and stability, with greater improvement in the pain score than of the other parameters. Radiological migration of the prosthesis was a frequent finding although this did not always correlate with symptoms. Better results were obtained in cases of primary or secondary protrusio acetabuli than after the revision of previous total arthroplasties.     

The total condylar knee prosthesis: the first 5 years

The total condylar knee prosthesis evolved from previous experience with other prostheses at the Hospital for Special Surgery. This evolution includes patellar resurfacing. Subsequent modifications have led to the total condylar knee prosthesis II (a cruciate substituting prosthesis), and the total condylar knee prosthesis III (a TCP II with increased constraint). The surgical technique requires ligamentous balance with correction of preoperative deformity by a soft-tissue release. Subsequently a standard operation is performed. Four hundred and sixty-one knees were reviewed with a minimum of one year follow-up and a maximum of 5 years. Seventy-five per cent were osteoarthritic knees. Using the Hospital for Special Surgery Knee Rating Scale, the results were excellent in 312 knees (68%), good in 109 knees (23.5%), fair in 18 knees (4%) and poor in 22 knees (4.5%). Osteoarthritic knees (excellent or good 93.5%) did slightly better than rheumatoid knees (excellent or good 87%). Complications include 6 infections, 6 subluxations and 10 cases of component loosening. There were 15 reoperations (3%). The results approach total hip arthroplasty in quality and so far have not deteriorated with time.     

Buechel-Pappas total ankle prosthesis: results in patients 5 to 7 years postimplantation

This article presents a sampling of patients who are 5 to 7 years post-Buechel-Pappas total ankle replacement. The implantations were performed during the Buechel-Pappas clinical trials in the United States that began in November 1998. The author implanted 78 patients from 12 states who were 15 to 83 years old at the time of surgery; 85% or more of these patients have minimal pain or are pain-free despite the appearance of the prosthesis on radiographs.     

Cemented bipolar hemiarthroplasty for displaced intracapsular fracture in the mobile active elderly patient

Fifty-three patients who were independently mobile outside their home at the time of a displaced intracapsular fractured neck of femur were reviewed at a mean follow-up of 32 months after treatment with a cemented bipolar hemiarthroplasty. Forty-four had no or mild pain. Eleven of the sixteen able to walk 1 mile before fracture were able to do so at review, once significant co-morbidity was excluded. There were no dislocations. Two had been revised, one for technical failure. These results are significantly better than would be expected with conventional hemiarthroplasty in this group of patients. They are comparable with results of total hip replacement (THR) but without the risk of dislocation. Patients able to walk 1 mile before fracture regained their pre-fracture mobility significantly better than those able to walk 500 yards. We suggest that ability to walk 1 mile should define the mobile active elderly for future studies and in guiding treatment.     

Stem fracture with the Exeter prosthesis 3 of 27 hips followed for 10 years

We report the results of a 9-11-year clinical and radiographic follow-up of 27 Exeter prostheses in which cement pressurizing technique was employed. 3 stems fractured and 3 other stems and 1 cup underwent aseptic loosening. The remaining prostheses had satisfactory clinical and radiographic results. Stem subsidence was seen only as part of a loosening process. We suspect that the pronounced taper design is responsible for the poor results. While the slender and weak distal end is fixed in a thick cement mantle, the wide proximal part allows only a thin cement layer, easily subjected to mechanical disintegration. Proximal debonding increases both the stress on the distal part of the stem and the distal bone-cement interface shear stress. Hence, we believe that the same process underlies both the loosenings and the stem fractures. The presently employed Exeter stem is manufactured from the stronger Orthinox steel, which may diminish the risk for fracture, but it has retained the extreme taper design. It is not likely that a polished surface or improved cementing will prevent stem fracture. Therefore, one should still be concerned about late fractures of the Exeter stem.     

The medium-term results of the cemented Exeter femoral component in patients under 40 years of age

We evaluated the outcome of 104 consecutive primary cemented Exeter femoral components in 78 patients (34 men, 44 women) under the age of 40 years who underwent total hip replacement between October 1993 and May 2004. The mean age at operation was 31 years (16 to 39). No hip was lost to follow-up, but three patients (four hips) died. None of the deaths were related to the surgery. At a mean follow-up of 6.2 years (2 to 13), three femoral components had been revised for septic loosening. Using Kaplan-Meier survival analysis, the seven-year survival of the component with revision for any reason as the endpoint was 95.8% (95% confidence interval 86.67 to 98.7). The seven-year survival with aseptic femoral loosening as the endpoint was 100% (95% confidence interval 100). The cemented Exeter femoral component in patients under the age of 40 shows promising medium-term results. As it is available in a wide range of sizes and offsets, we could address all types of anatomical variation in this series without the need for custom-made components.     

Total hip arthroplasty with the porous-coated anatomic hip prosthesis: results at 11 to 18 years

The authors had previously reported good results with apparent fixation of a series of porous-coated anatomic hips at 2 to 4 years. In a larger series of 133 hips with porous-coated anatomic uncemented components, 91 hips in 82 patients were available for a follow-up of 11 years or greater. Although 3.1% of acetabular cups had migrated or had been revised at 2 to 4 years; at 11 to 18 years, there was 37% lysis, 21.7% migration, and 32.3% revision. For the femur at 2 to 4 years, there was 3.1% migration and 1.5% revision. At 11 to 18 years, there was 27.2% lysis (proximal only), 6.6% migration, and 3.2% revision. Survival analysis for migration or revision for the femoral was 94%, and for the acetabular component, 63%, deteriorating markedly after 10 years.     

The Exeter Trauma Stem: A radiographic follow-up at minimum of five years post implantation

IntroductionThe Exeter Trauma Stem (ETS) has been recommended by National Institute of Clinical Excellence (NICE) guidelines in the United Kingdom as a proven, cemented stem. A single laboratory study in the literature has raised possible concerns about the polished finish of the ETS and subsequent potential for accelerated loosening although there is little clinical evidence to support or refute this.MethodsThe aim of this study was to assess clinical outcomes of the ETS at a minimum of five years post implantation. Primary outcomes were radiological loosening at a minimum of five years along with survivorship of the implant. Patient demographics were prospectively collected and followed up.Results218 ETS’s (in 214 patients) were implanted from June 2002 until August 2008 in a single centre by a wide variety of surgeons of differing grades. Of these, 16 underwent revision surgery for fracture (2), dislocation (3), infection (1) and acetabular erosion (10) but there were no revisions for aseptic loosening of the implant. There were 64.0% (137/214) patients that had died by the time of this study. Of the remaining patients, 90 had radiographs of their hips at a minimum of 5 years with 36 of these at a minimum of 7 years post implantation. None of these had evidence of loosening.ConclusionThe ETS is a robust and suitable stem for implantation in patients with hip fractures. There are no clinical suspicions or increased rates of loosening with the ETS in our study. The concerns about surface finish are not borne out in our clinical study which shows no evidence of loosening at a minimum of five years post operation. It confers many advantages including ease of revision and it should continue to be used as per NICE guidelines.     

Experience with bipolar prosthesis in femoral neck fractures in the elderly and debilitated

Eighty-eight bipolar Bateman hip endoprostheses for medial femoral neck fractures were implanted. The average age of the patients was 75 years. Intrahospital results proved the morbidity and mortality rates to be well within acceptable limits. Thirty patients were followed during periods of 12-74 months (median, 33 months). According to Charnley evaluation, mobility was excellent and very good in 20 patients (86%). Good function was present in 63% of patients. The majority of patients belonged to category C as defined by Charnley. Mild pain was present in 19 patients (63%); in only two cases, involving severe rheumatoid arthritis, pain was clearly related to sinkage. Radiographically, no visible protrusion or socket wear was present. Periarticular ossification occurred in 19 patients, but this did not impair function.     

The AGC total knee prosthesis at average 11 years

A retrospective study of a series of 126 consecutive primary cemented total knee replacements using the AGC prosthesis is reported. Sixty-two knees were available for long-term review with an average clinical follow-up of 11.4 years (range, 8.4-13.6 years). The survivorship was 95%, defining the endpoint as revision of all components for any reason except sepsis. The average knee flexion was 110.9 degrees. The average Knee Society score was 91, and the average Knee Society Functional score was 67. There was no finding of tibial polyethylene failure, wear debris-generated osteolysis, or tibial or femoral loosening. Seven metal-backed patellae developed wear-through at an average of 80.4 months (7 of 126 for a 5.5% failure rate), with 3 (2.3%) resulting in complete revision. The authors continue to use the AGC prosthesis with an all-polyethylene patella. Compared with historical controls, the AGC has comparable survivorship.     

The long-stem bipolar prosthesis in surgery of the hip

More than 500 hips, with either displaced fractures of the femoral neck or primary or revision total hip arthroplasty, were treated by a straight, long-stem (305-mm), Bateman-type bipolar model (BBM). The BBM was not porous coated, and it is not cemented in place. The femoral component is secured in the femoral canal by means of biomechanical fixation. It is biologic by bone ingrowth through the fenestration in the proximal neck. It is mechanical by a snug fit in the isthmus and by three-point fixation within the shaft. The removed femoral head is morselized in the bone mill and packed into the prepared femoral canal to enhance a tight fit. The collar of the BBM transfers stress to the calcar. Postoperative roentgenograms show incorporation of bone graft within the fenestration of the prosthesis and no stress shielding of the calcar. The acetabulum requires reaming only if it is shallow or asymmetric. It usually presents no problem except in revision total hip arthroplasty. The present authors have used the BBM almost exclusively since 1981. After eight years, the BBM has stood up well to the test of time and presented few major problems.     

Bicentric bipolar hip prosthesis: A radiological study of movement at the interprosthetic joint

Background:

The bipolar hip prostheses after some time functions as a unipolar device. There is a need to change the design of bipolar hip prostheses to make it function as a bipolar device over a prolonged period of time. A bicentric bipolar hip prosthesis was used as an implant for various conditions of the hip. We evaluated the movement of this newly developed prosthesis at the interprosthetic joint radiologically at periodic intervals.

Materials and Methods:

Fifty two cases were operarted with the Bicentric bipolar prosthesis for indications like fracture neck of femur and various other diseases of the hip and were followed up with serial radiographs at periodic intervals to evaluate, what fraction of the total abduction at the hip was occurring at the interprosthetic joint.

Results:

In cases of intracapsular fracture neck of femur, the percentage of total abduction occurring at the interprosthetic joint at 3 months follow-up was 33.74% (mean value of all the patients), which fell to 25.66% at 1.5 years. In indications for bipolar hemireplacement other than fracture neck of femur, the percentage of total abduction occurring at the interprosthetic joint at 3 months follow-up was 71.71% (mean value) and at 1.5 years it was 67.52%.

Conclusion:

This study shows the relative preservation of inner bearing movement in the bipolar hip prosthesis with time probably due its refined design. Further refinements are needed to make the prosthesis work better in patients of intracapsular fracture neck femur.     

The Angelchik prosthesis: results and complications

Fifty-four patients who had the Angelchik antireflux prosthesis inserted during the period March 1981 to May 1985 were sent a questionnaire and their medical records were reviewed. Forty-four patients replied: 68% said that they were cured, 25% said they were improved and two patients (4.5%) said they were worse after the operation. Of those who replied, 93% would recommend the procedure to others with a similar condition, 89% have had no further heartburn, and 72% have had no further regurgitation. However, it would appear from the responses that eight patients (18% of those who replied) have significant dysphagia not present before operation, at times varying from 8 months to 4 years and 10 months from operation (mean 38.5 months). Six additional patients (14%) had temporary dysphagia, now resolved and five patients (11%) have persisting minor dysphagia not present pre-operatively. Five respondents are known to have postoperative heartburn, two of whom are known to have persisting oesophagitis with ulceration. Nine patients (20%) continue to experience regurgitation, related to dysphagia in eight. Three prostheses have been removed without replacement; one after an oesophageal leak (believed to be related to a simultaneous parietal cell vagotomy), one for severe dysphagia and one which was unsuccessfully used to hold reduced a very large hiatus hernia. Two prostheses have been replaced after they slipped down the stomach wall, one with the tapes detached. (This latter prosthesis was one of the original ones with the tapes attached to the ends of the prosthesis only--a problem which has since been rectified by the manufacturer.) General surgical complications are listed for completeness.     

The cemented retentive cup: preliminary results at three years

Some patients with grossly deficient soft-tissue attachments or neurologic impairment are often submitted to recurrent dislocation after total hip arthroplasty. This multifactorial complication is difficult to treat. For theses indications, we have developed a cemented constrained cup using a mobile retentive ring in a groove bellows the head equatorial plane. According to a retrospective series of 113 patients (40 for revision surgery and 73 for primary surgery) with 33.7 months of average clinical follow-up, we use this retentive cup to restore and maintain hip stability. This preliminary study needs to be continued for a longer period in order to obtain further information on development of radiolucent lines.     

Postoperative analgesia with minidose intrathecal morphine for bipolar hip prosthesis in extremely elderly patients

Purpose

It is known that an optimal dose of intrathecal morphine for analgesia after total hip arthroplasty in older patients is 0.1 mg. On the other hand, minidose intrathecal morphine (0.05 mg) is useful for analgesia after the transurethral resection of the prostate in elderly patients. We evaluated the postoperative analgesic effect of minidose intrathecal morphine after bipolar hip prosthesis in seniors (age 85 years or more) undergoing spinal anesthesia.

Methods

Twenty seniors undergoing bipolar hip prosthesis under spinal anesthesia were randomly allocated to one of two groups. Group A (n = 10) received intrathecal injection of 0.5% isobaric bupivacaine, 2.8 ml, and group B (n = 10) received intrathecal injection of 0.5% isobaric bupivacaine, 2.8 ml, plus morphine, 0.05 mg. Pain, nausea, and itching were evaluated using a numerical rating scale, ranging from 0 to 10, at 0, 4, 8, 12, and 24 h after the operation.

Results

The values on the numerical rating scale for pain in group B were significantly lower than those in group A at 4, 8, and 12 h after the operation. There were no significant differences between the groups in the values on the numerical rating scale for nausea or itching throughout the time course of the study. No patient in either group showed hypoxemia or respiratory depression throughout the time course.

Conclusion

The results show that minidose intrathecal morphine provides a good analgesic effect without side effects, and it would be an effective and safe procedure for bipolar hip prosthesis in seniors.