Biomedical subjects

J G Horne

Publications and source records attributed to J G Horne.

At least 19 recordsLinked to original sources

PubMed2005

Waiting for hip arthroplasty: economic costs and health outcomes.

This prospective cohort study of 153 patients aimed to determine the economic and health costs of waiting for total hip arthroplasty (THA). Health-related quality of life, using self-completed WOMAC and EQ-5D questionnaires, was assessed monthly from enrolment preoperatively to 6 months postsurgery. Monthly cost diaries were used to record costs. The mean waiting time was 5.1 months and mean total cost of waiting for surgery was NZ 4305 dollars(US 2876 dollars) per person (pp) (NZ 1 dollar = US 0.668 dollar). Waiting more than 6 months was associated with a higher total mean cost (NZ 4278 dollars/US 2858 dollars pp) than waiting less than 6 months (NZ 2828 dollars/US 1889 dollars pp; P < .01). Improvements from preoperative to postoperative WOMAC and EQ-5D scores were identified (P < or = .01). Waiting longer led to poorer physical function preoperatively (P < or = .01). Those with poor initial health status showed greater improvement in WOMAC (P = .0001) and EQ-5D (P = .003) measures by 6 months after surgery. Longer waits for total hip arthroplasty incur greater economic costs and deterioration in physical function while waiting.

Adult↗

PubMed2003

An assessment of sleep disturbance in patients before and after total hip arthroplasty.

Patients with osteoarthritis commonly complain of sleep disturbance that may be due to pain. Osteoarthritic hip pain is commonly alleviated by total hip arthroplasty (THA). Forty-eight patients waiting for THA completed a sleep questionnaire and were monitored using actigraphy and sleep diaries for 4 to 5 nights, 1 month before and 3 months after surgery. For the group as a whole, significant improvements were seen in subjective and objective measures of sleep after THA. In this study, 75% of participants reported that their sleep was never or rarely disturbed by hip pain after surgery. Actigraphy indicated significant reductions in time in bed and activity during sleep, more efficient sleep and less fragmented (restless) sleep. Differences between patients aged < 65 and > or = 65 years were observed. These findings support the hypothesis that relief from the pain of osteoarthritis as a result of THA improves sleep quality. Improvements in sleep contribute to the improved quality of life and day-to-day functioning seen after THA.

Adult↗

PubMed2002

The effect of different cement insertion techniques on the bone-cement interface.

Since the introduction of cemented total hip arthroplasty, the method of cement usage has evolved through several generations. These changes may have been responsible for an improvement in femoral component longevity. The nature of the bone-cement interface in first-generation cementing techniques has been described, but the bone-cement interface in more recent cementing techniques has not. This article describes the bone-cement interface after 2 different cementing techniques in a canine total hip arthroplasty model.

Animals↗

PubMed1999

Donor site morbidity in the iliac crest bone graft.

BACKGROUND: Open iliac crest bone grafting is a common surgical procedure with recognized short-term complications. The present paper documents the medium- to long-term complications and level of patient satisfaction following the procedure. METHODS: Seventy-three patients undergoing an open iliac crest bone graft over the past 6 years at Wellington Hospital were retrospectively reviewed. All patients completed a postal questionnaire which assessed their current pain, sensory changes in and below the scar, scar appearance and overall appearance with the bone graft donor site. RESULTS: Sixteen patients (21.9%) reported pain, 11 patients (15%) stated that their scar was sensitive to touch and 19 patients (22%) reported a degree of sensory change below the scar. Six patients (8.2%) felt that the scar appearance was totally unacceptable. Overall satisfaction, however, was high with 70 patients (95.8%) 'fairly satisfied' or 'totally satisfied' with their iliac crest donor site. CONCLUSIONS: Bone grafting from the iliac crest is a relatively benign procedure in terms of patient satisfaction, and the most significant morbidity is pain.

Adolescent↗

PubMed1999

Assessment of polyethylene wear in total hip replacement.

The three-dimensional technique is a method for the measurement of polyethylene wear in patients with total hip joint replacement. Application of image processing technology allows automation of point selection from digital images of radiographs scanned into the computer. Validation of image processing modifications reveals a three-fold increase in accuracy and a 40-fold increase in reproducibility compared with manual input of points from a digitizer during bench testing. A review of three-dimensional technique application to clinical patients gives information on the factors that influence polyethylene wear. Increasing age, activity level, femoral head size, decreasing polyethylene thickness, and insertion of total hip prostheses without cement all increase polyethylene wear. Restoration of femoral offset during total hip replacement seems to decreases polyethylene wear. No apparent difference in polyethylene wear rate could be found between two groups of patients, one group had a stainless steel-polyethylene articulation and the other had a ceramic-polyethylene articulation. Measurement of the serial polyethylene wear of individual patients reveals a high rate of femoral head penetration during the first 2 years after total hip replacement using metal-backed acetabular components inserted without cement. Interpretation of this femoral head penetration as true polyethylene wear may be erroneous, however, because creep of the polyethylene and acetabular liner movement within its metal shell cannot be measured.

Arthroplasty, Replacement, Hip↗

PubMed1997

Three-dimensional polyethylene wear of a press-fit titanium prosthesis. Factors influencing generation of polyethylene debris.

Between 1985 and 1990, 108 consecutive Harris-Galante I (Zimmer, Warsaw, IN) total hip arthroplasties were performed by four surgeons at a single hospital. At the time of follow-up evaluation, 80 hips were available for review. The mean rate of linear wear was 0.15 mm/y, mean rate of three-dimensional femoral head displacement was 0.21 mm/y, and mean rate of volumetric wear was 121 mm3/y. Eight hips (10%) in this series had radiologic osteolysis around either the femoral or acetabular component. A significantly greater volumetric wear rate was found in patients who were younger, those with a higher activity level, those who received a 32-mm-diameter femoral head, and those with vertical orientation of their acetabular component. No relationship could be made with patient weight, gender, Harris hip score, or cup diameter.

Adult↗

PubMed1997

Measurement of polyethylene wear in acetabular components inserted with and without cement. A randomized trial.

We measured the three-dimensional wear of polyethylene after total hip arthroplasty with a titanium metal-backed Mallory-Head prosthesis that was inserted with cement in sixty-nine patients (sixty-nine hips) and with a press-fit titanium metal-backed Mallory-Head prosthesis that was inserted without cement in seventy patients (seventy hips). A modular titanium femoral head was used in all of the hips. The patients in the present study were part of a larger double-blind randomized trial comparing the result of total hip arthroplasty performed with cement with that of the same procedure performed without cement in 250 patients. The criterion for inclusion in the study of polyethylene wear was a minimum duration of follow-up of four years, which was met by 148 patients. As adequate radiographs for digitization were not available for nine patients, 139 patients were included in the present study. The age of the patient, the postoperative Harris hip score, the diameter of the femoral head, the thickness of the liner in the polar region of the acetabular component, and the duration of follow-up were similar for the two groups. The mean rate of volumetric wear of the polyethylene was significantly greater in the prostheses that had been inserted without cement than in those that had been inserted with cement (155.1 cubic millimeters per year compared with 98.5 cubic millimeters per year; p = 0.000008). Thirty-four (49 per cent) of the seventy hips in which the prosthesis had been inserted without cement had evidence of osteolysis on radiographs, compared with twelve (17 per cent) of the sixty-nine hips in the other group (p = 0.0002). Osteolysis was associated with an increased rate of polyethylene wear only in the hips in which the prosthesis had been inserted without cement.

Acetabulum↗

PubMed1995

The posteroanterior 45 degrees flexion weight-bearing radiograph of the knee.

Biomechanical studies suggest that radiographs of the osteoarthritic knee taken in 30 degrees to 60 degrees of flexion more accurately demonstrate the true degree of articular cartilage loss than radiographs taken with the knee in full extension. Conventional anteroposterior weight-bearing full-extension radiographs were compared with posteroanterior 45 degrees flexion weight-bearing radiographs of 35 patients with 45 symptomatic knees (90 compartments) presenting with suspected osteoarthritis. In 35 compartments, there was a 2-mm or greater loss of joint space in the 45 degrees flexion views compared with those taken in full extension. Also, in 11 compartments (10 knees), there was a normal joint space on the full extension radiographs, but marked narrowing on the flexion view. Both results are statistically significant. It is concluded that the posteroanterior 45 degrees flexion weight-bearing radiograph is a useful additional tool in the assessment of knees with early degenerative change.

Adult↗

PubMed1995

Measurement of polyethylene wear in metal-backed acetabular cups. I. Three-dimensional technique.

A new technique, the 3-dimensional technique, has been developed. Using a digitzer, points taken from anteroposterior and lateral radiographs are input into a personal computer. A 3-dimensional solid model of the prosthesis is created using custom software. Tilt and anteversion of the acetabular cup are measured, and the model is rotated to a standard frontal view, allowing measurement of femoral head displacement from the center of the acetabular cup. Comparing serial radiographs of the same patient gives the direction and distance of femoral head displacement over time, and this value is used to calculate the minimum volume of polyethylene debris generated. The 3-dimensional technique has been validated by construction of a precision acrylic phantom, and milling of a metal-backed acetabular cup to simulate polyethylene wear. Three-dimensional measurement of femoral head displacement using this technique has an accuracy of +/- 0.15 mm, and volume calculations are within 8% of the true amount of polyethylene removed from the cup. The 3-dimensional technique gives previously unavailable information, and can be used for clinical evaluation of polyethylene wear and evaluation of new prosthetic designs and bearing surfaces.

Acetabulum↗

PubMed1993

The relationship between proximal femoral anatomy and osteoarthrosis of the hip.

Proximal femoral anatomy in the anteroposterior plane was assessed by analysis of roentgenograms and the relationship between the anatomy and the pattern of osteoarthrosis of the hip was explored. The neck-shaft angle, the height of the femoral head, and the offset of the femoral head were analyzed and the type of osteoarthrosis classified according to Cameron and McNab. There was a significantly greater neck-shaft angle and a greater head height in the upward and outward migratory group. Patients being treated with total hip arthroplasty who exhibit certain types of proximal femoral anatomy might be expected to have increased acetabular loading and thus greater acetabular and femoral head wear. These data may have significance in the design of femoral components and the choice of implants in patients being treated with hip arthroplasty.

Femur↗

PubMed1990

Heterotopic ossification following uncemented total hip arthroplasty.

Heterotopic ossification following an uncemented total hip arthroplasty should theoretically demonstrate a higher incidence than a cemented arthroplasty. This is due to increased production of bone debris following vigorous femoral canal and pelvic reaming, which should provide increased stimulatory factors for ectopic bone production. The authors examined 196 consecutive primary total hip arthroplasties prospectively for 1 year. The overall incidence of heterotopic ossification was 26% with only one patient having a Grade III (severe) amount of ectopic bone. This incidence is consistent with those reported in cemented total hip arthroplasties. This paper does not support Puzas et al theory of bone dust providing a stimulatory factor for the production of heterotopic bone.

Aged↗

PubMed1990

A prospective randomized trial of external fixation and plaster cast immobilization in the treatment of distal radial fractures.

Distal radial fractures are common, and many methods of treatment have been reported but there are no studies that compare the different treatment methods. This randomized prospective study demonstrated no advantage in using an external fixator to immobilize reduced distal radial fractures over closed reduction and plaster cast immobilization in patients less than 60 years of age. The external fixator group had a significant complication rate.

Aged↗

PubMed1990

Hip fractures: a future epidemic?

Recent studies from the United Kingdom and Sweden have demonstrated a dramatic rise in the number of people with hip fractures. It is our hypothesis that New Zealand is experiencing a similar rise in the number of hip fractures. The number of elderly people (over age 65 years) admitted to public hospitals in New Zealand over a 38-year period was reviewed. In people over age 75 years, we observed a disproportionate increase in the number of fractures compared with the increase in population. The highest risk group was women over age 85 years. Because of the differing age-specific fracture rates, the proportion of females over age 85 increased from 17% in 1950 to 40% by 1987. Through weighted regression analysis of fracture rate and population predictions, the projected number of fractures in the year 2001 and 2011 was predicted. By 2011 the number of people sustaining hip fractures will more than double. The proportion of the very elderly (85+) will increase from 40 to 65%.

Aged↗

PubMed1989

Rhodococcus equi: an emerging opportunistic pathogen?

Human infection with Rhodococcus equi is apparently rare with most published reports describing the development of lung abscesses in immunocompromised hosts. Of only 18 cases of infection previously recorded, four have recently occurred in patients with the acquired immune deficiency syndrome (AIDS). In Australasia, R. equi has frequently been isolated from soil and infected farm animals yet no human infections have been reported thus far. Three cases of R. equi infection have occurred in New Zealand and, collectively, they cover a wider spectrum of disease than that previously recognised. The natural history of R. equi infections, their clinical features and treatment are described in the light of our recent experience.

Acquired Immunodeficiency Syndrome↗

PubMed1988

The outcome of fractures of the distal radius in young adults.

Fractures of the distal radius in young adults are not uncommon, but have received little attention in the literature. This paper reports a series of 40 fractures of the distal radius. The quality of reduction was found to relate directly to the final result. The authors suggest that open reduction and internal fixation be used more frequently in the management of this fracture.

Adolescent↗

PubMed1987

Candida albicans vertebral osteomyelitis in chronic renal failure.

Invasive candidal infections are encountered with increasing frequency in compromised hosts but bone infection is uncommon. A woman with systemic lupus erythematosus and end-stage renal failure managed by continuous ambulatory peritoneal dialysis developed a painful thoracic kyphosis and a lytic lesion in the vertebral bodies of T10 and T11. Blood cultures were sterile but bone biopsy material contained Candida albicans which also grew on culture. Circulating immune complexes were measured in high levels and contained candida antigens and specific anti-candida antibody as determined by isoelectric focusing, immunoblotting and immunoprinting techniques. Pain persisted after anti-fungal therapy had sterilized the lesion necessitating surgical excision of affected vertebrae, kyphosis correction and iliac crest bone grafting. The titres of circulating immune complexes and anti-candidal precipitins closely paralleled the clinical course.

Adult↗

PubMed1982

The assessment of skin viability using fluorescein angiography prior to amputation.

Fluorescein angiography was used for the preoperative assessment of skin viability and the determination of the level of amputation in patients with peripheral vascular disease. In twenty-two patients requiring twenty-seven lower-extremity amputations (including five revisions), a retrospective comparison was made between the surgeon's choice of amputation level based on clinical criteria and that based on the fluorescein angiogram. As was evident by the failure of the amputation to heal, the surgeon's prediction was too distal in nine (33 per cent) of twenty-seven amputations and revisions. The assessor of fluorescein angiograms predicted five of these nine failures; therefore, the failure rate could have been reduced to four (15 per cent) of twenty-seven amputations. The amputation level predicted on the basis of the fluorescein angiogram was unnecessarily high in three lower limbs (11 per cent). These three amputations healed at the level chosen by the surgeon, but did so by prolonged secondary healing. Fluorescein angiography is a simple, safe, and useful preoperative bedside technique for the assessment of skin viability and the determination of amputation level in patients with peripheral vascular disease.

Aged↗

PubMed1981

Olecranon fractures: a review of 100 cases.

Olecranon fractures in the adult are a common upper extremity injury. There is still no universally accepted classification of these fractures and no uniformity of treatment. Results stated vary considerably, and support can be found in the literature for any of several forms of operative treatment. A review of the literature on olecranon fractures is presented. A system of classification of these fractures based on lateral roentgenograms is proposed; Type I, IIa, IIb, and III (depending on location in the olecranon). An assessment of the results of treatment of 100 patients with such fractures treated by surgical methods is presented. Open reduction and internal fixation with tension band, screws, plate and screws, or band, plate, and screws can be relied upon for satisfactory end results. Type I fractures can be treated by anatomic reduction and tension band wiring; all Type II fractures by tension band technique; Type III fractures with a plate and screws.

Adolescent↗