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Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_1 | Pages 15 - 15
1 Jan 2022
Tamboowalla KB Gandbhir V Nagai H Wynn-Jones H Talwalker S Kay P
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Abstract

Background

The COVID-19 pandemic has strongly impacted elective orthopaedic surgery. At our trust, a geographically discrete elective site deals with planned orthopaedic surgery. There was a need to define a green pathway to deliver surgical care safely and efficiently, and tackle mounting waiting lists.

Methods

Records of patients operated at our elective site, between 1st July 2020 and 14th January 2021, under a green pathway, including pre-operative self-isolation, COVID screening and segregating perioperative patients, were reviewed, and analysed retrospectively. Patients who did not attend (DNA) their post-operative follow-up appointments were identified. Finally, regional COVID incidence was compared with that in our centre.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_10 | Pages 34 - 34
1 Aug 2021
Ramavath A Leong J Siney P Kay P Divecha H Board T
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Principles of bone preservation and restoration of biomechanical alignment should be followed during revision total hip arthroplasty (THA). Where possible, conservative femoral revision techniques and even reconstructive de-escalation involving using primary stems should be considered. This study aims to investigate the outcome of patients who have undergone conservative femoral revision THA in our Institution.

We retrospectively identified patients from our Institution's revision arthroplasty database who had cemented, or un-cemented primary stems implanted during revision THA of a previous stemmed femoral implant. Our primary outcome measure was all-cause re-revision THA with a secondary outcome measure of improvement in Oxford hip score (OHS). Radiographic evidence of stem loosening and post-op complications were recorded.

Between 02/12/2014 to 12/12/2019, there were 226 patients identified with a mean follow up of 2 years (1–5 years). The majority of cases were represented by Paprosky type 1 (63%) and type 2 (25%) femoral defects. There were 45 patients (20%) who underwent impaction bone grafting (IBG) and 43 patients (19%) who had a cement in cement (CinC) femoral revision and cemented primary stem in 137 (60%), 1 uncemented stem with no IBG or CinC revision. Kaplan Meier survival for all-cause re-revision THA was 93.7% (95% CI: 88.3 – 100) at 3 years. The reasons for re-revision included 4 periprosthetic fractures, 4 dislocations, 1 deep infection, 1 loosening of femoral component and 1 loosening of acetabular component. Pre- and post-operative OHS scores were available in 137 hips (60%) with a mean improvement of 13. Radiographic review revealed 7% of cases with evidence of loosening in 1 or more Gruen zones.

Our early results support the use of conservative femoral revision THA techniques where appropriate, with low complication and re-revision rates. Revisions using primary femoral components, where appropriate, should be considered in surgical planning to avoid unnecessary reconstructive escalation.


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_6 | Pages 21 - 21
1 May 2019
Syam K Saraogi A Siney P Jones H Purbach B Nagai H Kay P
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Background

Revision total hip arthroplasty (THA) is a challenging scenario following complex primary THA for developmental dysplasia of hip (DDH). This study envisages the long-term outcomes of revision DDH and the role of lateral structural support in socket fixation in these young patients who may require multiple revisions in their life-time.

Materials and methods

Hundred and eighteen consecutive cemented revision THAs with minimum follow up of 5 years following primary diagnosis of DDH operated by a single unit between January 1974 and December 2012 were analysed for their clinical and radiological outcomes.


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_3 | Pages 11 - 11
1 Apr 2019
Syam K Saraogi A Siney P Nagai H WynnJones H Purbach B Kay P
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Revision total hip arthroplasty (THA) is a challenging scenario following complex primary THA for developmental dysplasia of hip (DDH). Our study envisages the long-term outcomes of revision DDH and the role of lateral structural support in socket fixation in these young patients who may require multiple revisions in their life-time.

Hundred and eighteen consecutive cemented revision THAs with minimum follow up of 5 years following primary diagnosis of DDH operated between January 1974 and December 2012 were analysed for their clinical and radiological outcomes.

The mean follow-up of 118 patients was 11.0 years (5.1–39.6 years). The Kaplan Mier survivorship at 11 years with end point as revision for any reason was 89.8% (CI 81.1–98.4). Of 118 revisions, 88 acetabular revisions were for aseptic loosening. Out of the acetabular revisions, 21 had pre-existing structural bone grafts from primary surgery, of which only 3 needed structural re-grafting during revision. Amongst the remaining 18 hips, the lateral support from the previous graft facilitated revision with no requirement of additional structural graft. Sixty-three hips did not have any form of grafting during primary operation. Amongst them, 35 had bone grafting in revision surgery (18 structural grafting).

This study reports the largest number of revision THAs with primary diagnosis of DDH with the longest follow up. In our experience, the lateral support from the structural graft done in primary operation appears to have provided benefit in subsequent revision socket fixation.


The Bone & Joint Journal
Vol. 100-B, Issue 1 | Pages 20 - 27
1 Jan 2018
Sabah SA Moon JC Jenkins-Jones S Morgan CL Currie CJ Wilkinson JM Porter M Captur G Henckel J Chaturvedi N Kay P Skinner JA Hart AH Manisty C

Aims

The aim of this study was to determine whether patients with metal-on-metal (MoM) arthroplasties of the hip have an increased risk of cardiac failure compared with those with alternative types of arthroplasties (non-MoM).

Patients and Methods

A linkage study between the National Joint Registry, Hospital Episodes Statistics and records of the Office for National Statistics on deaths was undertaken. Patients who underwent elective total hip arthroplasty between January 2003 and December 2014 with no past history of cardiac failure were included and stratified as having either a MoM (n = 53 529) or a non-MoM (n = 482 247) arthroplasty. The primary outcome measure was the time to an admission to hospital for cardiac failure or death. Analysis was carried out using data from all patients and from those matched by propensity score.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_1 | Pages 11 - 11
1 Jan 2018
Saraogi A Lokikere N Siney P Nagai H Purbach B Raut V Kay P
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Introduction: Revision hip arthroplasty for aseptic loosening of femoral component is successfully treated with impaction bone grafting technique. Owing to easier technique and shorter operative time, distally fixed non-cemented long stems have gained popularity in the present era. However, use of long stems could make subsequent re-revision difficult due to further bone loss. The standard length stem has been often critiqued due to apprehension of peri-prosthetic fracture.

This study aims to determine the long-term outcomes of the impaction bone grafting of the femur for aseptic loosening in revision hip arthroplasty using standard length C-stems. 168 total hip revisions of 162 patients with impaction bone grafting and cemented standard C-stem (done with standardized technique) between 1995 and 2008 at a tertiary referral centre were included. Revisions for infection and segmental bone defects were excluded.

Mean follow-up of the 168 revision hips was 10.5 years (range 5 – 19.1 years). 14 patients (8.3%) were re-revised, reasons being, persistent deep infection (1.8%), repeated dislocations (1.2%), cup loosening (4.8%) and stem loosening (1.2%). Only 1 patient (0.6%) was re-revised due to stem loosening alone. No peri-prosthetic fractures (intra-operative or post-operative) or stem breakage were identified.

Use of standard stem length in hip revisions with impaction bone grafting does not increase the risk of peri-prosthetic fractures, instead, reconstitutes the bone stock. This questions the conventional principle of bypassing the distal cavitation of femur by 2 cortical diameters with the use of long stem. In our experience, a good proximal femur support is key to performance of standard length cemented stems in revision for aseptic loosening irrespective of grade of distal cavitation for cavitatory defects of femur when treated with impaction bone grafting.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_17 | Pages 10 - 10
1 Nov 2017
Sidharthan S Lokikere N Saraogi A Nagai H Wynn-Jones H Board T Shah N Porter M Kay P
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Background

One of the major concerns of hinge knees have been reported in literature is mechanical failure. Failure in the form of component fracture (2–10%) and hinge dislocation/ failure are worrisome. In addition, higher risk of aseptic loosening with hinge knee prosthesis has been attributed to stress transfer at bone cement interface.

Methods

Retrospective review of clinical and radiological results of 71 consecutive patients operated at single centre using Smiles hinge knee (Stanmore implants) between 2010 and 2014. Data was collected till the latest follow up. Mechanical failure due to any reason was considered as primary end point. Radiological evidence of aseptic loosening was considered to be one of the surrogate end points.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_12 | Pages 20 - 20
1 Jun 2017
Lokikere N Saraogi A Nagai H Kay P
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In patients with primary hip replacement for previous infective arthritis the risk of recurrence of infection is of major concern. In addition, the safe time interval post infective arthritis for primary hip replacement is not known.

Clinical & radiological results of consecutive series of 80 primary hip replacements performed for septic / tuberculous arthritis at Wrightington hospital from 1970 to 2008. Data was collected till latest follow up. Re-infection or revision for any reason was considered as primary end point for survivorship.

Average age at primary hip replacement was 55.55 years (24 – 75). Mean follow up was 14.47 years (2–41). Twelve patients in septic hip group (n=42) needed revision out of which 6 (14%) were for infection. The survival rate for recent septic arthritis group (<10 years) was 60% at 7.5 years, whereas in old septic arthritis group (>10 years) it was 94.45% at 15.3 years, considering infection as end point. The survival rate was 60% for recent septic arthritis and 78.13% for old septic arthritis group over the same period of time considering revision for any reason as end point. In tuberculous group (n=38), the survival rate was 76.32% at 14.5 years of follow up, considering revision for any reason as end point.

Significantly high re-infection rate in patients with recent septic arthritis was noted. No recurrence of infection in patients with old septic arthritis. No reactivation of tuberculosis in tuberculous arthritis group.

This is the largest series with longest follow-up on primary total hip replacement for infective arthritis till date. Recent septic arthritis (<10Y) was a statistically high risk factor for recurrence of infection. Old septic arthritis is reasonably safe with 94.45% success rate at 15 years follow up. Old tuberculous arthritis is not a risk factor for hip replacement


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_14 | Pages 10 - 10
1 Jul 2016
Saraogi A Lokikere N Siney P Nagai H Purbach B Raut V Kay P
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The choice of stem length in total hip revision with impaction bone grafting of femur is essentially based upon the grade of cavitation of femur and surgeon's preference. The standard length stem has been often critiqued for the apprehension of peri-prosthetic fracture. Our study highlights the importance of proximal bone stock rather than distal cavitation in determining the length of femoral stem.

168 total hip revisions of 162 patients with impaction bone grafting and cemented standard C-stem (done with standardized technique) between 1995 and 2008 at a tertiary referral centre were included. Revisions for infection and segmental bone defects were excluded. Serial radiographs were retrospectively analysed by two people independently, using Endoklinik classification, Gruen zones and more and outcomes were analysed.

Mean follow-up of the 168 revision hips was 10.5 years (range 5 – 19.1 years). 14 patients (8.3%) were re-revised, reasons being, persistent deep infection (1.8%), repeated dislocations (1.2%), cup loosening (4.8%) and stem loosening (1.2%). Only 1 patient (0.6%) was re-revised due to stem loosening alone. No peri-prosthetic fractures or stem breakage were identified.

Use of standard stem length in hip revisions with impaction bone grafting doesn't increase the risk of peri-prosthetic fractures even during long term follow up period. This questions the principle of bypassing the distal cavitation of femur by 2 cortical diameters with the use of long stem. In our experience, a good proximal femur support aids in the performance of standard length cemented stems in revision for aseptic loosening irrespective of grade of distal cavitation for cavitory defects of femur treated with impaction bone grafting.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_14 | Pages 7 - 7
1 Jul 2016
Lokikere N Saraogi A Sonar U Porter M Kay P Wynn-Jones H Shah N
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Distal femoral replacement is an operation long considered as salvage operation for neoplastic conditions. Outcomes of this procedure for difficult knee revisions with bone loss of distal femur have been sparsely reported.

We present the early results of complex revision knee arthroplasty using distal femoral replacement implant, performed for severe osteolysis and bone loss.

Retrospective review of clinic and radiological results of 25 consecutive patients operated at single centre between January 2010 and December 2014. All patients had single type of implant. All data was collected till the latest follow up. Re-revision for any reason was considered as primary end point.

Mean age at surgery was 72.2 years (range 51 – 85 years). Average number of previous knee replacements was 2.28 (range 1 to 6). Most common indications were infection, aseptic loosening and peri-prosthetic fracture. Average follow up was 24.5 months (range: 3–63 months). 1 patient died 8 months post-op due to unrelated reasons. Re-revision rate was 2/25 (8%) during this period. One was re-revised for aseptic loosening and one was revised for peri-prosthetic fracture of femur. Two other peri-prosthetic fractures were managed by open reduction and internal fixation. All 3 peri-prosthetic fractures occurred with low energy trauma.

It is noteworthy that there was no hinge or mechanical failures of the implant. Peri-prosthetic fracture in 12% of patients in this series is of concern. There are no similar studies to compare this data with. The length of the stem, type of fixation of the stem, weight of the distal femoral component of implant can be postulated as factors contributing to risk of peri-prosthetic fracture.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_11 | Pages 33 - 33
1 Jun 2016
Bhaskar D Nagai H Kay P
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Introduction

Limb Length discrepancy after total hip replacement has been reported to happen in 1–27% of cases with differences up to 70mm. Occasionally revision THR has been used to achieve limb length equalisation, especially when patients are symptomatic with hip/back pain, neurologic symptoms or instability. However, in presence of a well-functioning, pain free hip without hip symptoms, revision THR for shortening can lead to problems with decrease in offset or stability. An option in these cases would be a distal shortening osteotomy of femur.

Materials and Methods

From 2005 to 2014 five shortening osteotomies were done for LLD with limb lengthening of ipsilateral side following THR. All patients had well-functioning THRs with and no complications as dislocations or nerve symptoms.

A distal metaphyseal shortening osteotomy, fixed using a 95 degree blade plate, was chosen for better healing at this level and ease of surgery.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_13 | Pages 4 - 4
1 Jun 2016
Mohammed R Siney P Purbach B Kay P
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Structural bulk autografts restore the severe bone loss at primary hip arthroplasty in dysplastic hips and have shown to have good long term outcomes. There are only a few reports of revision arthroplasty for these sockets that fail eventually. We report on a series of such primary hips which underwent cemented revision of the socket for aseptic loosening and their outcomes.

A retrospective review was performed from our database to identify fifteen acetabular revisions after previous bulk autograft. The mean age at revision was 53.9 years (range 31–72.1). The mean duration between the primary and revision arthroplasty was 12.4 years (range 6.6 – 20.3). All procedures were done using trochanteric osteotomy and three hips also needed the femoral component revision. All fifteen hips needed re-bone grafting at the revision surgery to restore the new socket to the level of the true acetabulum. Of these ten hips had morsellised impaction allograft, and the remaining five also needing a structural bulk allograft.

Two sockets underwent re-revision at mean 7.5 years for aseptic loosening. One patient had a dislocation that was reduced closed. At a mean follow up of 5.7 years, one socket showed superior migration, but was stable and did not need further intervention. Two other sockets also showed radiological evidence of loosening, and are being closely monitored.

The medium term results of cemented acetabular revision in this younger age group are satisfactory, with repeat bone grafting being required to restore the true acetabular position. Though the primary arthroplasty with bulk bone graft recreates the acetabular bone stock, significant bone loss due to the mechanical loosening of the socket needs to be anticipated in revision surgery.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_11 | Pages 29 - 29
1 Jun 2016
Purbach B Siney P Jones HW Kay P Wroblewski B
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Introduction

Primary hip replacement in young active patients is on the increase. Due to the demands set by the patient, implants used in this patient group should have a proven long-term clinical and radiological outcome. We report our results in patients under the age of 50 using the C-Stem femoral component – a cemented triple tapered polished stem.

Methods

Since the C-stem femoral component was introduced into clinical practice in 1993, 6906 C-stems have been used in primary hip replacements at our hospital. In this group, 896 patients were under the age of 50 at the time of surgery. We report the first 300 consecutive C-stems from this group. The surgical technique of using a bone block to allow subsidence and clearing of the calcar to increase loading of the proximal femur medially was routinely used together with a femoral cement gun and pressurizer.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_1 | Pages 167 - 167
1 Jan 2013
Morris C Kumar V Sharma S Morris M Raut V Kay P
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Financial impact and patient satisfaction with four different anticoagulants for hip and knee arthroplasty in patients with a previous history of VTE- A prospective randomised trial

Introduction

New generation oral anticoagulants (dabigatran/rivaroxaban) have recently become available for the prevention of venous thromboembolism (VTE) following hip and knee arthroplasty. Traditional therapies (warfarin/low molecular weight heparins) are less costly, but have several limitations.

The aim of this study was to evaluate the financial impact of substituting enoxaparin and warfarin with newer therapies dabigatran and rivaroxaban. A secondary objective was to investigate patient satisfaction with these treatments.

Methods

A randomised prospective study was conducted over a 12 month period. Patients with a history of VTE undergoing hip or knee replacement were randomised to receive one of four anticoagulants for five weeks post surgery. Information was gathered during the hospital stay and then post discharge, by telephone, for five weeks(35 days)to determine costs. The costs included cost of drug, nursing time, blood monitoring and transport costs. The patients were also asked to complete the Duke Anticoagulation Satisfaction Scale (DASS). The DASS is a 26 item questionnaire which has 7 responses for each question.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIX | Pages 170 - 170
1 Sep 2012
Nickinson R Fleming P Siney P Board T Purbach B Wroblewski M Kay P
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Introduction

We present the outcome of 297 acetabular revisions using bone grafting and cemented acetabular components in 297 patients, with a mean follow-up of 8 years 3 months (5–20 years).

Methods

All patients underwent acetabular revision with allograft bone grafting and insertion of cemented acetabular components. Of the 297 patients, 134 patients (45%) were male and 163 (55%) were female. The mean age of undergoing revision surgery with bone grafting was 60 years (25–87 years). The mean weight at revision surgery was 71.9 kg (40–128 kg). Post-operatively, all patients were reviewed regularly in out-patients, where they were examined clinically for any complications and their radiographs were examined for evidence of graft union, radiological lucency and cup migration.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIX | Pages 82 - 82
1 Sep 2012
Chandran P Patel K Kumar V Hamed Y Kay P Porter M
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Introduction

We aim to assess the functional outcome, patient perceived satisfaction and implant survival at a mean follow up of 13[10–16] years following revision knee replacement.

Patients and Methods

Between 1995 and 2001, 243 revision knee replacements were performed in 230 patients using Endolink [Link, Hamburg] or TC3 [Depuy, Leeds] prosthesis at Wrightington hospital, Wrightington, were consented to take part in this study. Data was collected prospectively which includes complications and functional assessment by Oxford knee score, WOMAC, HSS, UCLA, SF12 scores, and patient satisfaction questioner. The scores were obtained pre-operatively and post-operatively at 1 year, 5 years and at the latest follow-up. The mean age was 69 yrs, 51% were males, TC3 prosthesis as used in 175 and Endolink in 68, the revision was for Infection in 71[29%], 53 patients had intra-operative positive culture, 35 had 2 stage revision.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIX | Pages 9 - 9
1 Sep 2012
Purbach B Wroblewski B Siney P Fleming P Kay P
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The C-Stem in its design as a triple tapered stem, is the logical development of the original Charnley flat-back polished stem. The concept, design and the surgical technique cater for a limited slip of the stem within the cement mantle transferring the load more proximally.

Five thousand two hundred and thirty three primary procedures using a C-stem have been carried out since 1993. We reviewed all 621 cases that had their total hip arthroplasty before 1998.

Sixty nine patients (70 hips) had died and 101 hips had not reached a ten-year clinical and radiological follow-up and had not been revised. Thirty-two hips had been revised before 10 years, none were revised for aseptic stem loosening and no stems. The indications for revision were Infection in 4, dislocation in 3, aseptic cup loosening in 24 and unexplained pain in 1.

The remaining 418 hips had a mean follow-up of 12 years (range 10–15 years). There were 216 women and 173 men, and 34 patients had bilateral LFAs. The patients' mean age at surgery was 53 years (range 16–83 years). Thirty four hips had been revised at the time of review. The reasons for revision were infection in 5, dislocation in 2, aseptic cup loosening in 24 and 1 for neuralgia paraesthetica where the stem was well fixed. Two hips were revised for stem fracture.

There were no revisions for stem loosening but 2 stems were revised for fracture - both with a defective cement mantle proximally. The clinical results are very encouraging and they support the concept of the Charnley cemented low friction arthroplasty, but place a demand on the understanding of the technique and its execution at surgery.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIX | Pages 237 - 237
1 Sep 2012
Chandran P Patel K Kumar V Hamed Y Kay P Porter M
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Introduction

We aim to assess the functional outcome, patient satisfaction and implant survival at a mean follow up of 13[10–16] years following revision for infected total knee replacement.

Patients and Methods

Between 1995 and 2001, 71 revision knee replacements were performed for infection, at Wrightington hospital, Wrightington. Data was collected prospectively which includes intra-operative cultures, complications and functional assessment by Oxford knee score, WOMAC, HSS, UCLA, SF12 scores, and patient satisfaction questioner. The scores were obtained pre-operatively and post-operatively at 1 year, 5 years and at the latest follow-up. Mean age was 69 yrs, 70% were Females, 31[44%] had 2 stage revisions and intra-operative culture was positive in 53 patients. Most common organism was staphylococcus aureus in 30% and staphylococcus epidermides in 18%.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_III | Pages 50 - 50
1 Feb 2012
Young P Austin E Bobak P Gray E Kay P
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Introduction

Modern processing techniques in bone banking are thought to decrease the presence of allogenic material in bone. This project was performed to observe any changes in peripheral blood lymphocyte subsets in response to allografted bone used in revision hip replacement.

Methods

87 patients were entered into this prospective study and grouped according to whether impaction allograft was used or not. Samples were collected pre-operatively and at set time intervals up to one year post-operatively. Using flow cytometry, analysis of venous blood allowed counts of the following cells: Helper T-lymphocytes, cytotoxic T-lymphocytes, memory T-lymphocytes, naïve T-lymphocytes, Natural Killer cells and B-lymphocytes.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_II | Pages 64 - 64
1 Feb 2012
Malik M Gray J Kay P
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We describe the association between post-operative femoral stem radiological appearances and aseptic failure of THA (total hip arthroplasty) following a retrospective review of records and radiographs of all patients attending for follow-up between August 2002 and August 2003 who had a cemented Charnley femoral stem and either a cemented polyethylene acetabular cup inserted. Femoral stem aseptic loosening was defined either by findings at revision surgery, the definite radiographic loosening criteria of Harris or progressive endosteal cavitation across zones as described by Gruen. Well-fixed control THAs were defined as those that demonstrated none of the radiographic features of aseptic loosening or ‘at risk’ signs as described by Wroblewski. Parameters measured were: Alignment, Barrack grade of cementation, cement mantle width of the cement mantle and the presence and width of any radiolucent lines.

Sixty-three hips were entered into the aseptic failure group and 138 into the control group. The alignment of the femoral stem was not associated with failure (p=0.283). Thickness of the cement mantle was statistically associated with failure in Gruen zones 6 (p=0.040) and Gruen zone 7 (p=0.003). A significant association for the presence of radiolucent lines was found for Gruen zones 3 (p=0.0001) and 5 (p=0.0001). The grade of cementation as measured by the Barrack grade was strongly associated with failure for grades C (p=0.001) and D (p=0.001).

This study has demonstrated that easily applied radiological criteria can be used to identify ‘at risk’ Charnley THAs from the immediate post-operative AP radiograph.