During open reduction of an irreducible anterior dislocation of a total hip replacement with an Oxinium femoral head, it was observed that the head had been significantly damaged. Gross and scanning electron microscopic examination revealed cracking, gouging, and delamination of the surface. Because of the risk which this poses for damaging the polyethylene acetabular liner, it is strongly recommended that patients with this type of prosthetic head be carefully monitored after a dislocation.
Acetabular component orientation in total hip arthroplasty (THA)
influences results. Intra-operatively, the natural arthritic acetabulum
is often used as a reference to position the acetabular component.
Detailed information regarding its orientation is therefore essential. The
aim of this study was to identify the acetabular inclination and
anteversion in arthritic hips. Acetabular inclination and anteversion in 65 symptomatic arthritic
hips requiring THA were measured using a computer navigation system.
All patients were Caucasian with primary osteoarthritis (29 men,
36 women). The mean age was 68 years (SD 8). Mean inclination was
50.5° (SD 7.8) in men and 52.1° (SD 6.7) in women. Mean anteversion
was 8.3° (SD 8.7) in men and 14.4° (SD 11.6) in women. Objectives
Methods
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.
The Motec cementless modular metal-on-metal ball-and-socket
wrist arthroplasty was implanted in 16 wrists with scaphoid nonunion
advanced collapse (SNAC; grades 3 or 4) and 14 wrists with scapholunate
advanced collapse (SLAC) in 30 patients (20 men) with severe (grades
3 or 4) post-traumatic osteoarthritis of the wrist. The mean age of
the patients was 52 years (31 to 71). All prostheses integrated
well radiologically. At a mean follow-up of 3.2 years (1.1 to 6.1)
no luxation or implant breakage occurred. Two wrists were converted
to an arthrodesis for persistent pain. Loosening occurred in one
further wrist at five years post-operatively. The remainder demonstrated close
bone–implant contact. The clinical results were good, with markedly
decreased Disabilities of the Arm Shoulder and Hand (DASH) and pain
scores, and increased movement and grip strength. No patient used
analgesics and most had returned to work. Good short-term function was achieved using this wrist arthroplasty
in a high-demand group of patients with post-traumatic osteoarthritis.
Dislocation is a common and well-studied complication after total hip replacement. However, subluxation, which we define as a clinically recognised episode of incomplete movement of the femoral head outside the acetabulum with spontaneous reduction, has not been studied previously. Out of a total of 2521 hip replacements performed over 12 years by one surgeon, 30 patients experienced subluxations which occurred in 31 arthroplasties. Data were collected prospectively with a minimum follow-up of two years. Subluxation occurred significantly more frequently after revision than after primary hip replacement, and resolved in 19 of 31 cases (61.3%). In six of the 31 hips (19.4%) the patient subsequently dislocated the affected hip, and in six hips (19.4%) intermittent subluxation continued. Four patients had a revision operation for instability, three for recurrent dislocation and one for recurrent subluxation. Clinical and radiological comparisons with a matched group of stable total hips showed no correlation with demographic or radiological parameters. Patients with subluxing hips reported significantly more concern that their hip would dislocate, more often changed their behaviour to prevent instability and had lower postoperative Harris hip scores than patients with stable replacements.
The aim of this study was to find anatomical
landmarks for rotational alignment of the tibial component in total knee
replacement (TKR) in a CT-based study. Pre-operative CT scanning
was performed on 94 South Korean patients (nine men, 85 women, 188
knees) with osteoarthritis of the knee joint prior to TKR. The tibial
anteroposterior (AP) axis was defined as a line perpendicular to
the femoral surgical transepicondylar axis and passing through the centre
of the posterior cruciate ligament (PCL). The angles between the
defined tibial AP axis and anatomical landmarks at various levels
of the tibia were measured. The mean values of the angles between
the defined tibial AP axis and the line connecting the anterior
border of the proximal third of the tibia to the centre of the PCL
was -0.2° (-17 to 14.1, Cite this article:
There are no recent studies comparing cable with
wire for the fixation of osteotomies or fractures in total hip replacement
(THR). Our objective was to evaluate the five-year clinical and
radiological outcomes and complication rates of the two techniques.
We undertook a review including all primary and revision THRs performed
in one hospital between 1996 and 2005 using cable or wire fixation.
Clinical and radiological evaluation was performed five years post-operatively.
Cables were used in 51 THRs and wires in 126, and of these, 36 THRs
with cable (71%) and 101 with wire (80%) were evaluated at follow-up.
The five-year radiographs available for 33 cable and 91 wire THRs
revealed rates of breakage of fixation of 12 of 33 (36%) and 42
of 91 (46%), respectively. With cable there was a significantly
higher risk of metal debris (68% In conclusion, we found a higher incidence of complications and
a trend towards increased infection and foreign-body reaction with
the use of cables.
The long-term results of grafting with hydroxyapatite granules for acetabular deficiency in revision total hip replacement are not well known. We have evaluated the results of revision using a modular cup with hydroxyapatite grafting for Paprosky type 2 and 3 acetabular defects at a minimum of ten years’ follow-up. We retrospectively reviewed 49 acetabular revisions at a mean of 135 months (120 to 178). There was one type 2B, ten 2C, 28 3A and ten 3B hips. With loosening as the endpoint, the survival rate was 74.2% (95% confidence interval 58.3 to 90.1). Radiologically, four of the type 3A hips (14%) and six of the type 3B hips (60%) showed aseptic loosening with collapse of the hydroxyapatite layer, whereas no loosening occurred in type 2 hips. There was consolidation of the hydroxyapatite layer in 33 hips (66%). Loosening was detected in nine of 29 hips (31%) without cement and in one of 20 hips (5%) with cement (p = 0.03, Fisher’s exact probability test). The linear wear and annual wear rate did not correlate with loosening. These results suggest that the long-term results of hydroxyapatite grafting with cement for type 2 and 3A hips are encouraging.
We prospectively followed 191 consecutive collarless
polished tapered (CPT) femoral stems, implanted in 175 patients
who had a mean age at operation of 64.5 years (21 to 85). At a mean
follow-up of 15.9 years (14 to 17.5), 86 patients (95 hips) were
still alive. The fate of all original stems is known. The 16-year
survivorship with re-operation for any reason was 80.7% (95% confidence
interval 72 to 89.4). There was no loss to follow-up, with clinical
data available on all 95 hips and radiological assessment performed
on 90 hips (95%). At latest follow-up, the mean Harris hip score
was 78 (28 to 100) and the mean Oxford hip score was 36 (15 to 48).
Stems subsided within the cement mantle, with a mean subsidence
of 2.1 mm (0.4 to 19.2). Among the original cohort, only one stem
(0.5%) has been revised due to aseptic loosening. In total seven
stems were revised for any cause, of which four revisions were required
for infection following revision of the acetabular component. A
total of 21 patients (11%) required some sort of revision procedure;
all except three of these resulted from failure of the acetabular
component. Cemented acetabular components had a significantly lower
revision burden (three hips, 2.7%) than Harris Galante uncemented
components (17 hips, 21.8%) (p <
0.001). The CPT stem continues to provide excellent radiological and
clinical outcomes at 15 years following implantation. Its results
are consistent with other polished tapered stem designs.
We have reviewed the rate of revision of fully cemented, hybrid and uncemented primary total hip replacements (THRs) registered in the New Zealand Joint Registry between 1999 and December 2006 to determine whether there was any statistically significant difference in the early survival and reason for revision in these different types of fixation. The percentage rate of revision was calculated per 100 component years and compared with the reason for revision, the type of fixation and the age of the patients. Of the 42 665 primary THRs registered, 920 (2.16%) underwent revision requiring change of at least one component. Fully-cemented THRs had a lower rate of revision when considering all causes for failure (p <
0.001), but below the age of 65 years uncemented THRs had a lower rate (p <
0.01). The rate of revision of the acetabular component for aseptic loosening was less in the uncemented and hybrid groups compared with that in the fully cemented group (p <
0.001), and the rate of revision of cemented and uncemented femoral components was similar, except in patients over 75 years of age in whom revision of cemented femoral components was significantly less frequent (p <
0.02). Revision for infection was more common in patients aged below 65 years and in cemented and hybrid THRs compared with cementless THRs (p <
0.001). Dislocation was the most common cause of revision for all types of fixation and was more frequent in both uncemented acetabular groups (p <
0.001). The experience of the surgeon did not affect the findings. Although cemented THR had the lowest rate of revision for all causes in the short term (90 days), uncemented THR had the lowest rate of aseptic loosening in patients under 65 years of age and had rates comparable with international rates of aseptic loosening in those over 65 years.
Our study aimed to examine not only the incidence but also the
impact of noise from two types of total hip replacement articulations:
ceramic-on-ceramic and ceramic-on-polyethylene. We performed a case-controlled study comparing subjective and
objective questionnaire scores of patients receiving a ceramic-on-ceramic
or a ceramic-on-polyethylene total hip replacement by a single surgeon.Objectives
Methods
Revision total hip replacement (THR) for young
patients is challenging because of technical complexity and the potential
need for subsequent further revisions. We have assessed the survivorship,
functional outcome and complications of this procedure in patients
aged <
50 years through a large longitudinal series with consistent treatment
algorithms. Of 132 consecutive patients (181 hips) who underwent
revision THR, 102 patients (151 hips) with a mean age of 43 years
(22 to 50) were reviewed at a mean follow-up of 11 years (2 to 26)
post-operatively. We attempted to restore bone stock with allograft
where indicated. Using further revision for any reason as an end point,
the survival of the acetabular component was 71% ( This overall perspective on the mid- to long-term results is
valuable when advising young patients on the prospects of revision
surgery at the time of primary replacement. Cite this article:
The highly cross-linked polyethylene Exeter RimFit flanged cemented
acetabular component was introduced in the United Kingdom in 2010.
This study aimed to examine the rates of emergence of radiolucent
lines observed when the Rimfit acetabular component was implanted
at total hip arthroplasty (THA) using two different techniques: firstly,
the ‘rimcutter’ technique in which the flange sits on a pre-prepared
acetabular rim; and secondly, the ‘trimmed flange’ technique in
which the flange is trimmed and the acetabular component is seated
inside the rim of the acetabulum. The radiographs of 150 THAs (75 ‘rimcutter’, 75 ‘trimmed flange’)
involving this component were evaluated to assess for radiolucencies
at the cement/bone interface by three observers. Aims
Patients and Methods
In 2005, we demonstrated that the polished triple-tapered
C-stem at two years had migrated distally and rotated internally.
From that series, 33 patients have now been followed radiologically,
clinically and by radiostereometric analysis (RSA) for up to ten
years. The distal migration within the cement mantle had continued
and reached a mean of 2 mm (0.5 to 4.0) at ten years. Internal rotation,
also within the cement mantle, was a mean 3.8° (external 1.6° to
internal 6.6°) The cement mantle did not show any sign of migration
or loosening in relation to the femoral bone. There were no clinical
or radiological signs indicating that the migration or rotation
within the cement mantle had had any adverse effects for the patients. Cite this article:
This retrospective study evaluated the midterm clinical and radiographic outcomes of a second-generation total knee replacement system. In a multicentre consecutive series of 1512 patients, 1970 knees were treated with the PFC Sigma knee system (Depuy, Warsaw, Indiana). The patients were reviewed for functional outcome, and underwent independent radiographic evaluation at a mean follow-up of 7.3 years (5 to 10). A total of 40 knees (2%) required revision, 17 (0.9%) for infection. The incidence of osteolysis was 2.2%. The ten-year survival with revision for any cause other than infection as the endpoint was 97.2% (95% CI 95.4 to 99.1). The PFC Sigma knee system appears to provide excellent results in the medium term.
Mechanical alignment has been a fundamental tenet of total knee arthroplasty (TKA) since modern knee replacement surgery was developed in the 1970s. The objective of mechanical alignment was to infer the greatest biomechanical advantage to the implant to prevent early loosening and failure. Over the last 40 years a great deal of innovation in TKA technology has been focusing on how to more accurately achieve mechanical alignment. Recently the concept of mechanical alignment has been challenged, and other alignment philosophies are being explored with the intention of trying to improve patient outcomes following TKA. This article examines the evolution of the mechanical alignment concept and whether there are any viable alternatives.
There have been several reports of good survivorship and excellent function at ten years with fixed-bearing unicompartmental knee replacement. However, little is known about survival beyond ten years. From the Bristol database of over 4000 knee replacements, we identified 203 St Georg Sled unicompartmental knee replacements (174 patients) which had already survived ten years. The mean age of the patients at surgery was 67.1 years (35.7 to 85) with 67 (38.5%) being under 65 years at the time of surgery. They were reviewed at a mean of 14.8 years (10 to 29.4) from surgery to determine survivorship and function. There were 99 knees followed up for 15 years, 21 for 20 years and four for 25 years. The remainder failed, were withdrawn, or the patient had died. In 58 patients (69 knees) the implant was in situ at the time of death. Revision was undertaken in 16 knees (7.9%) at a mean of 13 years (10.2 to 21.6) after operation. In seven knees (3.4%) this was for progression of arthritis, in three (1.5%) for
We evaluated 31 patients with bilateral dysplastic hips who had undergone periacetabular osteotomy for early (Tönnis grade 0 or 1) or moderate (Tönnis grade 2) osteoarthritis in one hip and total hip replacement for advanced (Tönnis grade 3) osteoarthritis in the other. At a mean follow-up of 5.5 years (2 to 9) after periacetabular osteotomy and 6.7 years (3 to 10) after total hip replacement, there was no difference in the functional outcome in hips undergoing osteotomy for early or moderate osteoarthritis and those with a total hip replacement, as determined by the Merle d’Aubigné and Postel score and the Western Ontario and McMaster Universities osteoarthritis index. More patients preferred the spherical periacetabular osteotomy to total hip replacement (53% vs 23%; p = 0.029). Osteoarthritis secondary to hip dysplasia is often progressive. Given the results, timely correction of dysplasia by periacetabular osteotomy should be considered whenever possible in young patients since this could produce a favourable outcome which is comparable with that of total hip replacement.
In 2004 we described the ten-year prospective results of 38 total hip replacements using the Furlong hydroxyapatite-ceramic-coated femoral component in 35 patients <
50 years old. We have now reviewed the surviving 35 arthroplasties in 33 patients at a mean of 16 years (10.3 to 19.9). The mean age of the surviving patients at the time of operation was 41.3 years (26.0 to 49.0). Of these, eight have undergone revision of their acetabular component for aseptic loosening. None of the femoral components has had revision for aseptic loosening giving a survival rate of 100% at 16 years (95% confidence interval 89% to 100%). The Furlong hydroxyapatite-ceramic-coated femoral component gives excellent long-term survival in young and active patients.