With greater numbers of younger patients undergoing
total hip replacement (THR), the effect of patient age on the diameter
of the femoral canal may become more relevant. This study aimed
to investigate the relationship between the diameter of the diaphysis
of the femoral canal with increasing age in a large number of patients
who underwent THR. A total of 1685 patients scheduled for THR had
their femoral dimensions recorded from calibrated radiographs. There
were 736 males and 949 females with mean ages of 67.1 years (34
to 92) and 70.2 years (29 to 92), respectively. The mean diameter
of the femoral canal was 13.3 mm (8.0 to 23.0) for males and 12.7
mm (6.0 to 26.0) for females. There was a poor correlation between
age and the diameter of the canal in males (r = 0.071, p = 0.05)
but a stronger correlation in females (r = 0.31, p <
0.001). The diameter of the femoral canal diameter of a female patient
undergoing THR could be predicted to increase by 3.2 mm between
the ages of 40 and 80 years, in contrast a male would be expected
to experience only a 0.6 mm increase during the same period. This
increase in the diameter of the canal with age might affect the
long-term survival of the femoral component in female patients. Cite this article:
We describe a new technique of reconstruction of the deficient acetabulum in cementless total hip arthroplasty. The outer iliac table just above the deficient acetabulum is osteotomised and slid downwards. We have termed this an iliac sliding graft. Between October 1997 and November 2001, cementless total hip arthroplasty with an iliac sliding graft was performed on 19 patients (19 hips) with acetabular dysplasia. The mean follow-up was 3.4 years (2 to 6). The mean pre-operative Harris hip score was 45.1 which improved significantly to 85.3 at the time of the final follow-up. No patient had post-operative abductor dysfunction. Incorporation of the graft was seen after two to three months in all patients. Resorption of the graft and radiolucencies were infrequent. This technique is a useful alternative to femoral head autografting when the patient’s own femoral head cannot be used.
In this paper, we will consider the current role
of metal-on-metal bearings by looking at three subtypes of MoM hip
arthroplasty separately: Hip resurfacing, large head (>
36 mm) MoM
THA and MoM THA with traditional femoral head sizes.
The December 2012 Hip &
Pelvis Roundup360 looks at: swimming against the tide with resurfacing; hip impingement surgery; the relationship between obesity and co-morbidities and joint replacement infection; cemented hips; cross-linked polyethylene notching; whether cement is necessary in oncological arthroplasty; and how total hip replacement may result in weight gain.
We report the use of an allograft prosthetic composite for reconstruction of the skeletal defect in complex revision total hip replacement for severe proximal femoral bone loss. Between 1986 and 1999, 72 patients (20 men, 52 women) with a mean age of 59.9 years (38 to 78) underwent reconstruction using this technique. At a mean follow-up of 12 years (8 to 20) 57 patients were alive, 14 had died and one was lost to follow-up. Further revision was performed in 19 hips at a mean of 44.5 months (11 to 153) post-operatively. Causes of failure were aseptic loosening in four, allograft resorption in three, allograft nonunion in two, allograft fracture in four, fracture of the stem in one, and deep infection in five. The survivorship of the allograft-prosthesis composite at ten years was 69.0% (95% confidence interval 67.7 to 70.3) with 26 patients remaining at risk. Survivorship was statistically significantly affected by the severity of the pre-operative bone loss (Paprosky type IV; p = 0.019), the number of previous hip revisions exceeding two (p = 0.047), and the length of the allograft used (p = 0.005).
Migration of the acetabular component may give rise to oval-shaped bone defects in the acetabulum. The oblong implant is designed to fill these defects and achieve a stable cementless anchorage with no significant bone loss. We prospectively reviewed 133 oblong long oblique revision components at a mean follow-up of 9.74 years (0.6 to 14). All had been used in revisions for defects of type IIB to IIIB according to Paprosky. Aseptic loosening was the reason for revision in 11 cases (8.3%) and deep infection in seven (5.3%). The probability of implant survival over a 12-year follow-up estimated by the Kaplan-Meier method gave a survival rate of 0.85% respectively 0.90% when deep infection was excluded as the endpoint. Our study supports the use of these components in defects from IIB to IIIA. The main precondition for success is direct contact of more than half of the surface of the implant with the host acetabular bone.
We identified five (2.3%) fractures of the stem in a series of 219 revision procedures using a cementless, cylindrical, extensively porous-coated, distally-fixed femoral stem. Factors relating to the patients, the implant and the operations were compared with those with intact stems. Finite-element analysis was performed on two of the fractured implants. Factors associated with fracture of the stem were poor proximal bone support (type III–type IV; p = 0.001), a body mass index >
30; (p = 0.014), a smaller diameter of stem (<
13.5 mm; p = 0.007) and the use of an extended trochanteric osteotomy (ETO 4/5: p = 0.028). Finite-element analysis showed that the highest stresses on the stem occurred adjacent to the site of the fracture. The use of a strut graft wired over an extended trochanteric osteotomy in patients lacking proximal femoral cortical support decreased the stresses on the stem by 48%. We recommend the use of a strut allograft in conjunction with an extended trochanteric osteotomy in patients with poor proximal femoral bone stock.
Failure of total hip arthroplasty with acetabular deficiency occurred in 55 patients (60 hips) and was treated with acetabular revision using morsellised allograft and a cemented metal-backed component. A total of 50 patients (55 hips) were available for clinical and radiological evaluation at a mean follow-up of 5.8 years (3 to 9.5). No hip required further revision of the acetabular component because of aseptic loosening. All the hips except one had complete incorporation of the allograft demonstrated on the radiographs. A complete radiolucent line of >
1 mm was noted in two hips post-operatively. A good to excellent result occurred in 50 hips (91%). With radiological evidence of aseptic loosening of the acetabular component as the end-point, the survivorship at a mean of 5.8 years after surgery was 96.4%. The use of impacted allograft chips in combination with a cemented metal-backed acetabular component and screw fixation can achieve good medium-term results in patients with acetabular bone deficiency.
Immunosuppression following intra-articular injections of steroid into the hip may interfere with asepsis in a subsequent total hip arthroplasty (THA). We have undertaken a retrospective, matched, cohort study of infective complications after THA, in 40 patients who had received such an injection and 40 who had not. In the injection group there were five revisions, four of which were for deep infection. There were none in the matched group. The overall rate of revision in our database of 979 primary THAs was 1.02%. Six additional patients who had received injections underwent investigation for infection because of persistent problems in the hip as compared with one in the control group.
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We investigated the antibiotic concentration in fresh-frozen femoral head allografts harvested from two groups of living donors. Ten samples were collected from patients with osteoarthritis of the hip and ten from those with a fracture of the neck of the femur scheduled for primary arthroplasty. Cefazolin (1 g) was administered as a pre-operative prophylactic antibiotic. After storage at −80°C for two weeks the pattern of release of cefazolin from morsellised femoral heads was evaluated by an We concluded that allografts of morsellised bone from the femoral head harvested from patients undergoing arthroplasty of the hip contained cefazolin, which had been administered pre-operatively and they exhibited inhibitory effects against bacteria
Between 1988 and 1998 we implanted 318 total hip replacements (THRs) in 287 patients using the Plasmacup (B. Braun Ltd, Sheffield, United Kingdom) and a conventional metal-on-polyethylene articulation. The main indications for THR were primary or secondary osteoarthritis. At follow-up after a mean 11.6 years (7.6 to 18.4) 17 patients had died and 20 could not be traced leaving a final series of 280 THRs in 250 patients. There were 62 revisions (22.1%) in 59 patients. A total of 43 acetabular shells (15.4%) had been revised and 13 (4.6%) had undergone exchange of the liner. The most frequent indications for revision were osteolysis and aseptic loosening, followed by polyethylene wear. The mean Kaplan-Meier survival of the Plasmacup was 91% at ten years and 58% at 14 years. Osteolysis was found around 36 (17.1%) of the 211 surviving shells. The median annual rate of linear wear in the surviving shells was 0.12 mm/year and 0.25 mm/year in those which had been revised (p <
0.001). Polyethylene wear was a strong independent risk factor for osteolysis and aseptic loosening. The percentage of patients with osteolysis increased proportionately with each quintile of wear-rate. There is a high late rate of failure of the Plasmacup. Patients with the combination of this prosthesis and bearing should be closely monitored after ten years.
Despite the increasing interest and subsequent published literature on hip resurfacing arthroplasty, little is known about the prevalence of its complications and in particular the less common modes of failure. The aim of this study was to identify the prevalence of failure of hip resurfacing arthroplasty and to analyse the reasons for it. From a multi-surgeon series (141 surgeons) of 5000 Birmingham hip resurfacings we have analysed the modes, prevalence, gender differences and times to failure of any hip requiring revision. To date 182 hips have been revised (3.6%). The most common cause for revision was a fracture of the neck of the femur (54 hips, prevalence 1.1%), followed by loosening of the acetabular component (32 hips, 0.6%), collapse of the femoral head/avascular necrosis (30 hips, 0.6%), loosening of the femoral component (19 hips, 0.4%), infection (17 hips, 0.3%), pain with aseptic lymphocytic vascular and associated lesions (ALVAL)/metallosis (15 hips, 0.3%), loosening of both components (five hips, 0.1%), dislocation (five hips, 0.1%) and malposition of the acetabular component (three hips, 0.1%). In two cases the cause of failure was unknown. Comparing men with women, we found the prevalence of revision to be significantly higher in women (women = 5.7%; men = 2.6%, p <
0.001). When analysing the individual modes of failure women had significantly more revisions for loosening of the acetabular component, dislocation, infection and pain/ALVAL/metallosis (p <
0.001, p = 0.004, p = 0.008, p = 0.01 respectively). The mean time to failure was 2.9 years (0.003 to 11.0) for all causes, with revision for fracture of the neck of the femur occurring earlier than other causes (mean 1.5 years, 0.02 to 11.0). There was a significantly shorter time to failure in men (mean 2.1 years, 0.4 to 8.7) compared with women (mean 3.6 years, 0.003 to 11.0) (p <
0.001).
Between 1990 and 2000, 123 hips in 110 patients were reconstructed for aseptic loosening using impaction bone grafting with frozen, irradiated, morsellised femoral heads and cemented acetabular components. This series was reported previously at a mean follow-up of five years. We have extended this follow-up and now describe the outcome of 86 hips in 74 patients at a mean of ten years. There have been 19 revisions, comprising nine for infection, seven for aseptic loosening and three for dislocation. In surviving acetabular reconstructions, union of the graft had occurred in 64 of 67 hips (95.5%). Survival analysis for all indications at ten years was 83.3% (95% confidence interval (CI) 68 to 89) and 71.3% (95% CI 58 to 84) at 15 years. Acetabular reconstruction using irradiated allograft and a cemented acetabular component is an effective method of reconstruction, providing results in the medium- to long-term comparable with those of reported series where non-irradiated freshly-frozen bone was used.
The hip joint is commonly involved in multiple epiphyseal dysplasia and patients may require total hip replacement before the age of 30 years. We retrospectively reviewed nine patients (16 hips) from four families. The diagnosis of multiple epiphyseal dysplasia was based on a family history, genetic counselling, clinical features and radiological findings. The mean age at surgery was 32 years (17 to 63), with a mean follow-up of 15.9 years (5.5 to 24). Of the 16 hips, ten required revision at a mean of 12.5 years (5 to 15) consisting of complete revision of the acetabular component in three hips and isolated exchange of the liner in seven. No femoral component has loosened or required revision during the period of follow-up. With revision for any reason, the 15-year survival was only 11.4% (95% confidence interval 1.4 to 21.4). However, when considering revision of the acetabular shell in isolation the survival at ten years was 93.7% (95% confidence interval 87.7 to 99.7), reducing to 76.7% (95% confidence interval 87.7 to 98.7) at 15 and 20 years, respectively.
We describe a case of symptomatic focal femoral osteolysis around a screw hole distal to the hydroxyapatite-coated portion of a cannulated femoral component in a revision hip replacement. No locking screw had been inserted into this, the most proximal of the three distal holes for locking screws. The presence of polyethylene wear debris in the tissue excised from the lesion suggested that it had passed through the cannulated portion of the stem and out of the proximal unfilled distal locking hole, initiating an osteolytic reaction in an otherwise well-fixed stem. This case highlights an important design characteristic of such cannulated, uncemented femoral components. We recommend that the proximal aperture of these cannulated stems be occluded at implantation.
Surgical dislocation of the hip in the treatment of acetabular fractures allows the femoral head to be safely displaced from the acetabulum. This permits full intra-articular acetabular and femoral inspection for the evaluation and potential treatment of cartilage lesions of the labrum and femoral head, reduction of the fracture under direct vision and avoidance of intra-articular penetration with hardware. We report 60 patients with selected types of acetabular fracture who were treated using this approach. Six were lost to follow-up and the remaining 54 were available for clinical and radiological review at a mean follow-up of 4.4 years (2 to 9). Substantial damage to the intra-articular cartilage was found in the anteromedial portion of the femoral head and the posterosuperior aspect of the acetabulum. Labral lesions were predominantly seen in the posterior acetabular area. Anatomical reduction was achieved in 50 hips (93%) which was considerably higher than that seen in previous reports. There were no cases of avascular necrosis. Four patients subsequently required total hip replacement. Good or excellent results were achieved in 44 hips (81.5%). The cumulative eight-year survivorship was 89.0% (95% confidence interval 84.5 to 94.1). Significant predictors of poor outcome were involvement of the acetabular dome and lesions of the femoral cartilage greater than grade 2. The functional mid-term results were better than those of previous reports. Surgical dislocation of the hip allows accurate reduction and a predictable mid-term outcome in the management of these difficult injuries without the risk of the development of avascular necrosis.
We reviewed the results at nine to 13 years of 125 total hip replacements in 113 patients using the monoblock uncemented Morscher press-fit acetabular component. The mean age at the time of operation was 56.9 years (36 to 74). The mean clinical follow-up was 11 years (9.7 to 13.5) and the mean radiological follow-up was 9.4 years (7.7 to 13.1). Three hips were revised, one immediately for instability, one for excessive wear and one for deep infection. No revisions were required for aseptic loosening. A total of eight hips (7.0%) had osteolytic lesions greater than 1 cm, in four around the acetabular component (3.5%). One required bone grafting behind a well-fixed implant. The mean wear rate was 0.11 mm/year (0.06 to 0.78) and was significantly higher in components with a steeper abduction angle. Kaplan-Meier survival curves at 13 years showed survival of 96.8% (95% confidence interval 90.2 to 99.0) for revision for any cause and of 95.7% (95% confidence interval 88.6 to 98.4) for any acetabular re-operation.
We reviewed the long-term results at ten to 12 years of 118 total hip replacements in 109 patients using a second-generation hemispherical cementless acetabular component (Reflection) designed to address the problem of backside wear. Five patients (five hips) died and six patients (seven hips) were lost to follow-up. The remaining 98 patients (106 hips) had a mean age of 62.9 years (34.0 to 86.2) A rate of revision for aseptic loosening of 0.9%, and predictable results were found with respect to radiological evidence of fixation, lack of pain, walking ability, range of movement and function. One component was revised for aseptic loosening, and of the 101 hips (95.2%) that did not have a revision, minor osteolytic lesions of the pelvis were seen in six (5.9%). Kaplan-Meier survival analysis for the total cohort of 118 hips revealed a 96.4% survival at both ten (95% confidence interval 90 to 98) and 12 years (95% confidence interval 86 to 98).
