Primary total hip arthroplasty with a proximally HA-coated titanium femoral component: results at 10-15-year follow-up.

INTRODUCTION: Registries in both the United Kingdom and Sweden suggest that the popularity of uncemented femoral components is increasing. As this trend progresses, long-term survival data for such components are becoming increasingly more important. We present the results of a cohort of patients treated with the Omnifit (Stryker, Mahwah, NJ) femoral component with the follow-up of 10-15 years. METHODS: A prospective study was performed in our unit between 1996 and 2001. Patients were reviewed pre-operatively and then at 6, 12, 26 and 52 weeks post-operatively and annually thereafter. They were assessed clinically and radiographically, and the Merle d'Aubigne Postel (MDP) hip score was calculated at each visit. A visual analogue scale (VAS) score and satisfaction score were also recorded to assess patient satisfaction with their procedure. Specific enquiry was made regarding anterior thigh pain. Statistical calculations were performed using the Student's t test. Kaplan-Meier survival analysis was performed. RESULTS: One hundred and four patients (113 hips) were included (48 males, 56 females). Bilateral procedures were performed in nine patients. Mean age was 60.4 years (33-72 years). Mean follow-up was 12.9 years (10-15 years). Mean pre-operative MDP score was 8.8 (3-16) and VAS score 7.8 (1-10) with ten representing the most severe symptoms. At final follow-up, the average MDP and VAS scores were 16.9 (13-18) and 2.1 (0-6), respectively. High levels of satisfaction were reported by 96.1% of patients. Two dislocations and two cases of anterior thigh pain occurred. Four patients required revision surgery. Survival of the femoral component with revision for any reason as the end point was 96%. CONCLUSION: This prosthesis provides symptom relief, return to function and high levels of patient satisfaction in the long term. Survival of this component is comparable to the best results for primary total hip arthroplasty with any means of fixation.

Primary total hip arthroplasty with hydroxyapatite coated titanium femoral stems. Does design philosophy influence long term outcome?: Results of a prospective randomised controlled trial with follow-up of 10-15 years.

We present results of a prospective randomised controlled trial examining two cohorts of patients treated with proximally (Group A) and fully coated (Group B) femoral components with long term follow up. Patients were reviewed preoperatively and 6, 12, 26 and 52 weeks post operatively then annually. The Merle d'Aubigne Postel (MDP) hip score was used to assess clinical outcome. A Visual Analog Score (VAS) was also recorded. Statistical calculation was performed using the student's t- test and Kaplan Meier survival analysis. One hundred and four patients were included in group A and 103 patients in group B. Mean age was 60.4 years and 60.8 years respectively. Mean follow- up was 12.9 years. Mean pre-operative MDP scores were 8.8 and 9.5 in Groups A and B respectively. Mean pre-operative VAS score 7.8 and 7.4 respectively. At final follow up mean MDP and VAS were 16.9, 16.6 and 2.1, 2.4 respectively. Three femoral revisions occurred in Group A. Seven revisions occurred in Group B. Survival of the femoral component with revision for any reason as the end point was 96% in Group A and 94.8% in Group B. Both components produced symptomatic relief and similar revision rates. Thigh pain occurred only in Group A.

Primary total hip replacement with a Furlong fully hydroxyapatite-coated titanium alloy femoral component: Results at a minimum follow-up of 20 years.

We present the extended follow-up (≥ 20 years) of a series of fully hydroxyapatite-coated femoral components used in 72 primary total hip replacements (THRs). Earlier results of this cohort have been previously published. All procedures were performed between 1986 and 1991. The series involved 45 women and 15 men with 12 bilateral procedures. Their mean age at the time of surgery was 60 years (46 to 80) and the mean duration of follow-up was 22.5 years (20 to 25). At final follow-up, the mean Merle d'Aubigné and Postel hip scores were 5.5 (4.5 to 6), 3.8 (3.5 to 5) and 3.3 (3.0 to 5.0) for pain, mobility and function, respectively. Of the patients 92% were very satisfied at the time of final follow-up. There were seven revisions: six of the acetabular component for aseptic loosening and one of both the stem and the acetabular component for loosening due to deep infection. The survival of this prosthesis at 22.5 years with revision for any reason as the endpoint was 91.7% (95% confidence interval (CI) 84 to 99). Survival with aseptic loosening of the stem as the endpoint was 100% (95% CI 90 to 100). This prosthesis provides pain relief in the long term. Survival of this component is comparable to the best results for primary THR with any means of fixation.

Inter-observer reliability of detecting Dynesys pedicle screw using plain X-rays: a study on 50 post-operative patients.

Dynamic stabilisation system for the spine (Dynesys) relies on titanium screw purchase within the pedicle. Decision on osseointegration is important especially when the patient becomes symptomatic following initial good outcome. Loose screws make the construct non-functional especially in symptomatic patients. Removal of Dynesys may become necessary to control patient's symptoms. In this study, we report interobserver reliability of X-ray for the interpretation of Dynesys pedicle screw osseointegration based on the diagnosis of "halo zone" and "Double halo zones" surrounding loose screw. Lumbar spine X-ray images of 50 patients in two views (AP and lateral) were selected from a random sample of 420 Dynesys patients. The total number of pedicle screws reviewed in this study was 260. The investigators (observers) were asked to state whether or not each pedicle screw is loose using "radiolucent zone sign". Observers were two expert orthopaedic spine consultant surgeons and one expert consultant radiologist and four specialist registrars (SpR) in orthopaedics and radiology. SpR assessments were repeated after 4 months with instructions to use "double-halo sign" for loose screws. The evaluation of interobserver agreement was performed by obtaining a Kappa (K) index. Using "radiolucent zone sign", Kappa Index (KI) among three consultants was 0.2198 at 95% CI (0.0520, 0.4916) while for all of the seven assessors (3 consultants and 4 SpR), KI was 0.1462 at 95% CI (0.0332, 0.2592). The use of "double-halo sign" was associated with KI of 0.666 at 95% CI (SE 0.83) among all of the 4 SpR. Based on plain X-ray "radiolucent zone sign", the inter-observer reliability of detecting loose Dynesys pedicle screw was poor (Kappa index of 0.2). On the other hand, using plain X-ray "double-halo sign" was associated with improved inter-observer reliability and validity.

Standardised consent forms on the website of the British Orthopaedic Association.

The British Orthopaedic Association has endorsed a website, www.orthoconsent.com, allowing surgeons free access to a bank of pre-written consent forms. These are designed to improve the level of information received by the patient and lessen the risk of successful litigation against surgeons and Health Trusts.

Long-term results of a hydroxyapatite-coated femoral component in total hip replacement: a 15- to 21-year follow-up study.

Between 1986 and 1991 we implanted 331 consecutive Furlong hydroxyapatite-coated femoral components of a total hip replacement in 291 patients. A cemented acetabular prosthesis was used in 217 hips and a hydroxyapatite-coated component in 114. We describe the long-term clinical and radiological survival of the femoral component at a mean follow-up of 17.5 years (15 to 21). Only two patients (0.68%) were lost to follow-up. With revision of the femoral component for any reason as the endpoint, the survival at a mean of 17 years was 97.4% (95% confidence interval 94.1 to 99.5), and with revision for aseptic loosening as the endpoint it was 100%. The survival at a maximum of 21 years with revision of the femoral component for any reason as the endpoint was 97.4% (95% confidence interval 81.0 or 99.5). These results compare favourably with the best long-term results of cemented or uncemented femoral components used in total hip replacement.

A hydroxyapatite-coated Insall-Burstein II total knee replacement: 11-year results.

We report the clinical and radiographic outcome of a consecutive series of 138 hydroxyapatite-coated total knee replacements with a mean follow-up of 11 years (10 to 13). The patients were entered into a prospective study and all living patients (76 knees) were evaluated. The Hospital for Special Surgery knee score was obtained for comparison with the pre-operative situation. No patient was lost to follow-up. Radiographic assessment revealed no loosening. Seven prostheses have been revised, giving a cumulative survival rate of 93% at 13 years. We believe this to be the longest follow-up report available for an hydroxyapatite-coated knee replacement and the first for this design of Insall-Burstein II knee.

A retrospective clinical and radiographic review of 173 hydroxyapatite-coated screw cups with 5- to 10-year follow-up, showing low revision rates for fixation failure.

We reviewed the midterm results of 173 hydroxyapatite-coated screw cups. The average follow-up was 6.5 years (range, 5-9 years). The follow-up rate was 93%. Patients were assessed using the Merle D'Aubigne-Postel clinical scoring scale and by radiographic review. Two patients had revision surgery for recurrent dislocation (1.2%), 3 patients were revised for aseptic loosening (1.7%), 1 patient underwent revision surgery because of deep prosthetic infection (0.6%), and 2 patients were revised for polyethylene wear without loosening (1.2%), which gave a total revision rate of 4.7%. The average postoperative Merle D'Aubigne-Postel scores were 5.7 for pain, 5.5 for range of motion, and 5.4 for function.

Bracing for loss.

People find unexpected bad news aversive and often brace themselves by predicting the worst. Three experiments examined whether the pessimism is influenced by personal need. Students who differed in financial need learned that a billing error meant that some students would receive an additional bill from their university. Financially needy students were consistently pessimistic in predicting their likelihood of receiving a bill, whereas non-needy students were not. In addition, the experiments reveal that (a) the pessimism occurred for potential losses but not potential gains, (b) needy students were pessimistic about their own chances but not the chances of a friend, (c) the pessimism was not attributable to needy students' being more readily primed by the news of a possible bill or to needy students' having more experience with billing errors, and (d) the pessimism was specific to monetary losses and did not generalize to other events.

The results at nine to twelve years of the use of a hydroxyapatite-coated femoral stem.

We describe the clinical and radiological outcome of 100 consecutive total hip replacements in 86 patients using the JRI Furlong hydroxyapatite-coated femoral component. The follow-up was 100% at a mean of ten years (9.0 to 12.0). All 54 living patients (62 hips) were examined annually. Their mean Merle d'Aubigné score was 5.8/5.6/4.6. A total of 32 patients had died. Their notes at the last annual assessment recorded a similar outcome to that of the living patients. Radiographs showed no radiolucent lines around any femoral component and there were no signs of impending failure. One patient required excision arthroplasty, but the femoral component had been bonded satisfactorily. There have been no other revisions of femoral components. Our findings suggest that the hydroxyapatite coating gives a satisfactory prosthesis-bone interface which is preferable to any other system.

Successful 1-stage exchange total knee arthroplasty for fungal infection.

The case of a 75-year-old woman treated by 1-stage exchange arthroplasty for fungal infection of a total knee arthroplasty is reported.

The short form-36 health survey questionnaire in spine surgery.

The Short Form-36 (SF-36) health questionnaire has been put forward as a general measure of outcome in health care and has been evaluated in several recent studies in the UK. We report its use in three groups of patients after spinal operations and have compared it with the Oswestry and Low Back Pain disability scales. There was a significant correlation between all variables of the SF-36 and the low-back scores. The mental-health items had the weakest correlation. Our study shows that the SF-36 questionnaire is valid and has internal consistency when applied to these patients.

An in vitro study of the biomechanical effects of flexible stabilization on the lumbar spine.

STUDY DESIGN: Lumbar motion segments were tested in vitro to examine biomechanical changes after posterior fixation by a flexible device. OBJECTIVES: To assess changes in load distribution and conformation of vertebral structures after a flexible stabilization. This should provide the foundations for a scientific understanding of the immediate effects of this surgical procedure. METHODS: Hooks were placed over the proximal spinous process and the distal laminas of a motion segment and connected by a polyester braid. Tension applied to the braid then generated a compression of the posterior elements. The force between the articular facets, the displacement of the posterior anulus fibrosus of the intervertebral disc, and the change in the relative position of the adjacent vertebrae were measured as the applied tension was increased. RESULTS: Facet joint force, disc bulge, and vertebral angulation increased with applied tension until a position of "locking" was achieved, apparently when the bony margin of the superior half of the facet joint contacted the inferior pars interarticularis. A tension of between 50 to 100 N in the braid was required for this. Facet joint force was less than 40% of this, and disc bulge was only 0.15 mm. The extension of the motion segment was between 2 degrees and 8 degrees. CONCLUSIONS: The results suggest that if such a system is applied surgically, stabilization is produced by compaction of the bony margins of the facet joints. Only a relatively small proportion of the posteriorly applied load is carried by the facet joints themselves, and little angulatory change is expected with minimal disc bulge.

Dysphoria as a moderator of the relationship between perceived effort and perceived ability.

Although Heiderian logic (F. Heider, 1958) proposes an inverse relationship between ability and effort, research has uncovered dramatic individual differences in the judged relationship between the two. Some view ability and effort as positively related; others view them as negatively related. Study 1 explored dysphoria as a moderator of this relationship by gathering dysphoric and nondysphoric individuals' perceptions of their effort and ability on daily activities. Although ability and effort generally were positively related, dysphorics reported lower ability on high effort tasks. In Study 2, Ss rated their effort as high or low. Dysphorics discounted ability when effort was high; nondysphorics reported the greatest ability when they expended the greatest effort. Collectively, there was no support for an inverse relationship between ability and effort. However, dysphorics infer less ability than nondysphorics following high effort.

Antithrombotic properties of dermatan sulphate (MF 701) in haemodialysis for chronic renal failure.

The therapeutic potential of the glycosaminoglycan (GAG), dermatan sulphate (DS), as an antithrombotic agent in humans has yet to be established. We have performed dose ranging studies of DS to determine its effectiveness as an antithrombotic agent in patients (n = 6-8) undergoing haemodialysis for chronic renal failure. In an initial study, Study 1, i.v. bolus doses of 2-4 mg/kg and 5-6 mg/kg DS were given to patients dialysing with polyacrylonitrile hollow fibre (PAN HF) membranes. In a second crossover study, Study 2, performed using cuprophane hollow fibre (CHF) membranes, i.v. bolus doses of 3 mg/kg and 6 mg/kg DS were compared to a standard unfractionated heparin (UFH) regime that has been shown previously to inhibit fibrin formation. Further infusion studies, Study 3 and Study 4 evaluated the antithrombotic efficacy of an i.v. DS bolus of 3 mg/kg plus an i.v. infusion of DS 0.6 mg kg-1 h-1 and a DS bolus of 5 mg/kg plus an infusion of 1 mg kg-1 h-1 over 5 h, respectively. These studies were compared to standard UFH regimes in a randomised crossover design. Plasma levels of fibrinopeptide A (FPA) and thrombin-antithrombin (TAT) were used as markers of fibrin formation and thrombin generation during dialysis using both membranes. The changes in DS concentration following administration of the different doses were similar in Studies 1 and 2. However, the effectiveness of DS as an anticoagulant appeared to depend markedly on the different dialyser types used in the two studies.(ABSTRACT TRUNCATED AT 250 WORDS)

Pelvic underpinning: eight years' experience.

A new method to reconstruct major acetabular floor defects is described. It relies on the placement of special nails into each of the three bones of the hemipelvis. Curved lugs attached to the nails are coalesced using bone cement forming a platform onto which a standard acetabular prosthesis is located. Forty-seven cases are reported with a mean follow-up of 4.4 years (1 to 8). No loosening of an acetabular cup or migration of the device has occurred.

The relationship of hardiness, gender, and stress to health outcomes in adolescents.

The present study examined the relationship between the hardiness components of commitment, control, and challenge, and the experience of physical and psychological symptoms in a sample of 150 (75 male, 75 female) adolescents. A measure of psychosocial stress was included to permit an examination of whether the hardiness components interact with stress in predicting health outcomes. Analyses revealed main effects of stress, gender, and the hardiness components of commitment and control for several of the health measures. More important was the finding of a consistent interaction of stress, gender, and hardiness for several of the health measures. Whereas low-stress males experienced few physical and psychological symptoms regardless of their levels of commitment and control, high-stress males experienced more problems when they were low rather than high in either commitment or control. The hardiness components did not interact with stress in the prediction of health outcomes among females.