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Bone & Joint Open
Vol. 3, Issue 2 | Pages 107 - 113
1 Feb 2022
Brunt ACC Gillespie M Holland G Brenkel I Walmsley P

Aims

Periprosthetic joint infection (PJI) occurs in approximately 1% to 2% of total knee arthroplasties (TKA) presenting multiple challenges, such as difficulty in diagnosis, technical complexity, and financial costs. Two-stage exchange is the gold standard for treating PJI but emerging evidence suggests 'two-in-one' single-stage revision as an alternative, delivering comparable outcomes, reduced morbidity, and cost-effectiveness. This study investigates five-year results of modified single-stage revision for treatment of PJI following TKA with bone loss.

Methods

Patients were identified from prospective data on all TKA patients with PJI following the primary procedure. Inclusion criteria were: revision for PJI with bone loss requiring reconstruction, and a minimum five years’ follow-up. Patients were followed up for recurrent infection and assessment of function. Tools used to assess function were Oxford Knee Score (OKS) and American Knee Society Score (AKSS).


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_7 | Pages 2 - 2
1 May 2019
Holland G Brown G Goudie S Brenkel I Walmsley P
Full Access

Prosthetic joint infections provide complex management, due to often-difficult diagnosis, need for multiple surgeries and increased technical and financial requirements. “2 in 1” single stage approaches have been advocated due to reduction in risks, costs and complications. This study aimed to investigate the results of single stage revision using metaphyseal sleeves for infected primary Total Knee Replacement (TKR).

Prospective data was collected on all patients presenting with an infected primary TKR over an 8-year period (2009–17). All revision procedures were undertaken in a single stage using metaphyseal sleeves.

26 patients were included, 2 of which had previously failed 2 stage revision and 3 failed DAIR procedures. Mean age was 72.5. Mean BMI was 33.4. Median ASA 2. Mean time to revision was 3.5 years range 3 months to 12 years. Six patients had actively discharging sinuses at the time of surgery. Only 4 of the 26 patients had no positive microbiological cultures from deep tissue samples or joint aspirates.

Only one patient has a recurrence of infection. This patient did not require further surgery and is treated on long term antibiotic suppression and is systemically well.

There were statistically significant improvements in both the pain and function component of AKSS scores. There was no significant improvement in flexion, however mean extension and total range of movement both showed statistically significant improvements.

Using Metaphyseal sleeves in single stage revision for infected TKR are safe and lead to an improvement in pain, function and have excellent efficacy for eradication of infection.


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_12 | Pages 36 - 36
1 Oct 2018
Hamilton WG Brenkel I Barnett SL Allen PW Lesko J Dwyer K Kantor SR Clatworthy M
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Introduction

New implants for total knee arthroplasty (TKA) are frequently introduced with the promise of improved performance. Infrequently there is accompanying data to document relative performance. The goal of this study was to evaluate the outcomes of an implant widely used for decades (Existing TKA), compared to a new implant (New TKA) from the same manufacturer.

Methods

From October 2011-March 2015, 19 sites prospectively enrolled and implanted 752 Subjects with Existing TKA. Between November 2012 and May 2015, 23 sites (18 sites had enrolled Existing TKAs), implanted 1131 Subjects with the New TKA. Demographics were similar between groups. Subjects were seen preoperatively, <1-year, 1-year, and 2-years to collect patient reported outcome measures (PROMs), radiographs and any complications. PROMs consisted of Knee Injury and Osteoarthritis Outcome Score (KOOS) (permits WOMAC scoring), Oxford Knee Score (OKS), Patient's Knee Implant Performance (PKIP) and EQ5D-3L and a p-value of 0.01 was established for statistical significance for PROMs comparisons. Kaplan-Meier (KM) implant survivorship (revision of any component for any reason) estimates were calculated.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_4 | Pages 49 - 49
1 Feb 2017
Huey V Brenkel I Chang C Clatworthy M Hamilton W Howard J Kantor S Lesko J Nunley R Whittaker J Verdonk P
Full Access

Introduction

With the introduction of new technology in orthopaedics, surgeons must balance anticipated benefits in patient outcomes with challenges or complications associated with surgical learning curve for the technology. The purpose of this study was to determine whether the surgeon learning curve with a new multi-radius primary TKA system (primary TKA implant and instruments) designed for surgical team ease would impact clinical outcomes, surgical time and complications.

Materials & Methods

From November 2012 to July 2015, 2369 primary TKAs were prospectively enrolled in two multicenter studies across 50 sites in 14 countries with a new knee system (ATTUNE®) evenly balanced across four configurations: cruciate retaining or posterior stabilised with either fixed bearing or rotating platform (CRFB, CRRP, PSFB, PSRP). 2261 knees had a <1 year visit and 1628 had a greater than 1 year visit. These knees were compared to a reference dataset of 845 primary TKAs from three manufacturers in the same four configurations with currently available products (CURRENT-TKA). Demographics for ATTUNE and CURRENT-TKA were similar and typical for primary TKA. Operative times, clinical outcomes and a series of five patient reported outcomes were compared for ATTUNE vs. CURRENT-TKA. The first 10 ATTUNE subjects for each surgeon were defined as learning curve cases (N=520) and were compared to all later subjects (N=1849) and also with the CURRENT-TKA cases (N=845). Patient reported outcome measures and clinical outcome analyses were adjusted for covariates including patient demographics, pre-op assessment and days post-op.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_20 | Pages 88 - 88
1 Nov 2016
Howard J Brenkel I Chang C Clatworthy M Hamilton W Howard J Huey V Kantor S Lesko J Nunley R Verdonk P
Full Access

With the introduction of new technology in orthopaedics, surgeons must balance anticipated benefits in patient outcomes with challenges or complications associated with surgical learning curve for the technology. The purpose of this study was to determine whether surgeon learning curve with a new multi-radius primary TKA system and instruments designed to improve surgical team ease would impact clinical outcomes, surgical time, and complications.

From November 2012 to July 2015, 2369 primary TKAs were prospectively enrolled in two multicentre studies across 50 sites in 14 countries with a new knee system (NEW-TKA) evenly balanced across four configurations: cruciate retaining or posterior stabilised with either fixed bearing or rotating platform (CRFB, CRRP, PSFB, PSRP). 2128 knees had a<1 year visit and 1189 had a minimum 1 year visit. These knees were compared to a reference dataset of 843 primary TKAs from three manufacturers in the same four configurations with currently available products (CA-TKA). Demographics for NEW-TKA and CA-TKA were similar and typical for primary TKA. Operative times, clinical outcomes and a series of five patient reported outcomes were compared for NEW-TKA vs. CA-TKA. The first 10 New-TKA subjects for each surgeon were defined as learning curve cases (N=520) and were compared to all later subjects (N=1849). Patient reported outcome measure and clinical outcome analyses were covariate adjusted for patient demographics, pre-op assessment and days post-op.

Mean (SD) surgical time for NEW-TKA learning curve cases was 79.1 (24.3) minutes, which reduced thereafter to 73.6 (24.3) (p=0.002). Beyond 10 cases, there was a continued reduction in NEW-TKA surgical time (R-Squared = 0.031). After 10 cases, surgical time was on par with the mean (SD) 71.9 (21.6) for CA-TKA (p=0.078). PROM outcomes of the first 10 learning curve cases for NEW-TKA were not statistically different from later cases at less than 1 year or later when adjusted for relevant covariates including configuration, patient demographics, pre-op functional status, and time post-op (p-values > 0.01). PROM outcomes for NEW-TKA vs. CA-TKA under the same covariate adjustments showed a trend favoring KOOS ADL, Symptoms, and Sport and Recreation subscores at minimum 1 year (p-values < 0.01). The incidence of intraoperative operative site complications was 1.3% for the NEW-TKA learning curve cases which was similar to the 0.6% rate for historical CA-TKA (p=0.231) and the intraoperative complication rate for the NEW-TKA later cases was consistent with learning curve cases (p=0.158).

The introduction of new implants into the market place needs to have adequate data to support that they are safe and effective. Except for a minor increase in surgical time during the first 10 patients, this study found that surgeon learning curve with this new primary TKA system does not adversely affect patient short term outcomes and complication rates.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_12 | Pages 12 - 12
1 Jun 2016
Bucknall V Davidson E Chesney D Clayton R Short N Brenkel I
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Alcohol-based cutaneous disinfectant use is well established in the surgical environment. However, during scrubbing, volatile alcohols are inspired into the pulmonary system. With the recent reduction in the national drink driving limit, even low levels of detected breath alcohol can have legal implications. This study aimed to determine the extent to which passive inhalation of alcohol-based surgical hand disinfectant affects estimated percentage blood alcohol concentration (%BAC) on breathalyser testing.

Over a one week period (September 2015), 24 theatre team members (13 surgeons, 6 scrub staff and 5 anaesthetists) were prospectively recruited. The mean cohort age was 43.7 years (50% female). Participants were instructed to scrub for 90 seconds with an alcohol-based hand disinfectant comprising of the active ingredients (per 100g): propan-1-ol 30.0g, propan-2-ol 45.0g and mecetroniumetilsulphate 0.2g. Estimated %BAC was recorded immediately before and after scrubbing, and every five minutes thereafter until levels returned to 0.00%BAC. Results ≥ 0.05%BAC were deemed above the Scottish legal driving limit.

All participants exceeded the 0.05%BAC threshold on immediate post scrub testing. The mean peak %BAC was 0.12% (± 0.05) with a maximum BAC documented at ≥0.20% in four subjects. In all participants, the %BAC descended to zero over a period ranging from 10–30 minutes with a mean time to zero of 16.7 (± 4.8) minutes.

Following the use of alcohol-based surgical hand disinfectant, estimated blood alcohol concentrations detected on breath sampling can rise up to four times the Scottish driving limit which may have legal and professional ramifications.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_7 | Pages 51 - 51
1 May 2016
Brenkel I Graichen H Himden S Murphy J Parkinson R
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Introduction

Cross-linked polyethylene in total hip arthroplasty has demonstrated excellent long-term wear resistance, leading to its acceptance as the standard bearing used in hip replacement. Adoption in knee replacement has been tentative, as the cross-linking process can decrease the polyethylene mechanical properties. The current study's purpose was examining survivorship of a fixed bearing knee replacement system featuring a moderately cross-linked polyethylene (MXLK) bearing, a cobalt chrome (CoCr) tibial tray with a highly polished top surface, and a new polyethylene-to-tray locking mechanism. The MXLK is made of ultra-high molecular weight GUR1020 resin irradiated with 5 Mrad gamma radiation, followed by a free radical quenching remelting annealing process, above the 135 degree melting point, that provides wear and fatigue resistance, and oxidative stability.

Materials & Methods

From November 2005 to June 2008, 539 PFC Sigma primary total knee replacements (TKA's) were prospectively entered into this non-comparative, multicenter, multinational study. Average age at time of surgery was 67 years, 57% were female, average body mass index was 30.4 kg/m2, and the dominant diagnosis was osteoarthritis (97%). Kaplan-Meier (KM) survivorship was the primary endpoint with primary event definition being removal of any component for any reason. The time variable was one of the following: time to revision, time to death, or time to last follow-up. Additional endpoints included: American Knee Society scores (knee and function), Oxford Knee score (range 12 to 60), SF-12 scores; radiographically assessed rates of radiolucent lines (RLL's) and osteolysis. RLL's greater than 2mm were counted. Progressive RLL's were those increasing in width from an earlier follow-up interval. Adjacent RLL's were defined as RLL's in adjacent zones. Complete RLL's were defined as RLL's completely around a component. This report provides 5-year results in this ongoing study with a 10-year final endpoint.


Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_8 | Pages 24 - 24
1 Jun 2015
Heil K Wood A Brenkel I
Full Access

The PFC Sigma Cobalt Chrome Sigma (PFCSCC) was introduced in 2006, an update of the PFC Sigma designed to reduce backside wear. To help identify any significant early failures following its introduction, we prospectively identified all recipients over a one-year period. The patient's clinical, demographic and radiographic data, American Knee Society scores (AKSS), Oxford Knee scores (OKS) and SF-12 scores was recorded pre-operatively and at one, three and five years. 233 patients underwent 249 primary knee arthroplasties with the PFCSCC. Seventeen patients (19 knees) died and 29 patients (30 knees) were also lost to follow up at the five year point. The mean age was 66.6 (34–80) with 47.6% of the cohort being male. The mean five year follow-up was 1836 days (1530–2307). Five knees (2.2%) were revised for infection and three were revised for pain. The 5–year cumulative survival rate was 96.6% for any failure and 98.6% for aseptic failure. AKSS 32.6 (0–86.6) preoperatively, 80.7 (29–95) 5 years P < 0.001. OKS was 39.0 (22–53) preoperatively, 23.5 (4.7–42.3) 5 years P < 0.001. These results demonstrate a good early survivorship when compared to the old design PFC Sigma, however further follow-up to ten years is required.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_29 | Pages 28 - 28
1 Aug 2013
Brenkel I Sabnis B Walmsley P Maheshwari R
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Introduction:

Two-stage revision is a widely accepted and performed intervention for septic total knee arthroplasty (TKA), with an infection eradication rate exceeding 90% in most studies. The ‘2-in-1’ single stage revision has recently been reported to have favourable results.

Aim:

To evaluate the early clinical results of single-stage reimplantation of infected TKA using stepped metaphyseal femoral and tibial sleeves.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_29 | Pages 64 - 64
1 Aug 2013
Sabnis B Maheshwari R Walmsley P Brenkel I
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Blood loss following total hip replacement is a major contributor to increase morbidity and length of stay. Various techniques have been described to reduce its occurrence. We now follow a set protocol, combining rivaroxaban for thrombo-prophylaxis and tranexamic acid to reduce immediate postoperative bleeding.

Patients and methods:

Using data collected prospectively we looked at 2 groups of consecutive patients undergoing THR. The protocol was the only factor changed during the period studied. Initially we used subcutaneous dalteparin injections and continued use of aspirin in peri-operative period following total hip replacements (Group I–317 patients).

A new protocol was introduced involving rivaroxaban for thrombo-prophylaxis with its first dose at least 8 hours from skin closure and stopping aspirin at least 7 days before operation. In addition tranexamic acid was given in a dose of 500 mg (or 1 gm in obese patients) intravenously just prior to incision (Group II–348 patients).

We compared these two groups regards Hb drop at 24 hours and blood transfusion requirement.

Results:

The average Hb drop at 24 hours postop in group I was 3.08 gm/dl compared to 2.31 in group II. (p<0.001). 62 (19.6%) patients in group I required blood transfusion compared to 11 (3.2%) in group II. (p = 0.001) Perioperative blood loss and length of stay reduction was also significantly different.

There was no increase in number of DVT/PE, but the sample size was too small to assess this statistically.


The Bone & Joint Journal
Vol. 95-B, Issue 2 | Pages 177 - 180
1 Feb 2013
Arthur CHC Wood AM Keenan ACM Clayton RAE Walmsley P Brenkel I

We report ten-year clinical and radiological follow-up data for the Sigma Press Fit Condylar total knee replacement system (Sigma PFC TKR). Between October 1998 and October 1999 a total of 235 consecutive PFC Sigma TKRs were carried out in 203 patients. Patients were seen at a specialist nurse-led clinic seven to ten days before admission and at six and 18 months, three, five and eight to ten years after surgery. Data were recorded prospectively at each clinic visit. Radiographs were obtained at the five- and eight- to ten-year follow-up appointments. Of the 203 patients, 147 (171 knees) were alive at ten years and 12 were lost to follow-up. A total of eight knees (3.4%) were revised, five for infection and three to change the polyethylene insert. The survival at ten years with an endpoint of revision for any reason was 95.9%, and with an endpoint of revision for aseptic failure was 98.7%. The mean American Knee Society Score (AKSS) was 79 (10 to 99) at eight to ten years, compared with 31 (2 to 62) pre-operatively. Of 109 knee with radiographs reviewed, 47 knees had radiolucent lines but none showed evidence of loosening.

Cite this article: Bone Joint J 2013;95-B:177–80.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XLI | Pages 90 - 90
1 Sep 2012
Wood A Davis A Keenan A Arthur C Brenkel I
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Current literature comparing the effect on body mass index (BMI) on the outcome of total hip replacements (THR) is inconclusive. To describe the effect of BMI on THR over the first five years.

We prospectively recruited 1,617 patients undergoing primary THR for osteoarthritis and followed them up at 5 years, recording, dislocations, revisions, deep and superficial infections, Harris Hip scores (HHS) and SF-36. A multivariate analysis was performed to identify if BMI is an independent predictor of adverse outcome.

148 (9%) patients had a BMI >35. 6.8% of patients with a BMI >35 had a dislocation by 5 year post op compared with 3.2%BMI 30–34.9, 2% BMI 25–29.9 and 1.5% BMI<25 (p=0.03) Superficial infections 14.2% BMI >35, 4.4% BMI <25. In SF 36 scores only Mental Health and change in health had no significant differences with an increase in BMI having a statistically significant decrease in all other SF scores. HHS had a mean improvement of 45.1 at five years with an expected loss of 0.302 HHS points (95% CI0.440–0.163) per 1 point BMI increase. There was no significant difference in deep infections, mortality <3 months, revision rates or length of stay.

The most significant risk in increasing BMI is the dislocation rate, possibly representing increased technical difficulty in larger patients. Whilst increasing BMI has a reduced HHS and SF16 score, the overall benefit is still positive.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XLI | Pages 16 - 16
1 Sep 2012
Smith R Wood A Keenan A Sabnis B Walmsley P Brenkel I
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The risk of venous thrombo-embolism (VTE) is high in orthopedics. Oral direct factor Xa inhibitors have been introduced to help reduce the incidence of VTE. To reduce post-operative bleeding antifibrinolytics are used. We aimed to ascertain the effect of two drugs on post operative bleeding and transfusion requirements.

We prospectively recorded patient demographics, operative details, complications, transfusion incidence and VTE incidence in TKR patients. We also sent out questionnaires to patients asking about wound bleeding and VTE. All patients were given 10mg Rivaroxaban 8 hours post operatively and then OD for 14 or 35 days. Patients given tranexamic acid were given 500mg IV, 5 minutes prior to wound closure at the discretion of the surgeon. VTE was Deep Vein Thrombus or Pulmonary Embolism confirmed by Doppler or CTPA. Minor bleed was categorized as dressing soakage or reported wound leakage, major bleed as hematoma requiring revision within 30 days.

509 patients underwent TKR: 200 (39%) received Rivaroxaban only (Group 1), 296 (58%) also received tranexamic acid (Group 2). 13 (3%) patients had no data available. Five patients had a VTE: 4 (2%) in Group 1, 1 (0.3%) in Group 2 [P<0.05]. 39 patients had a minor bleed: 17 (8.5%) in Group 1, 22 (7.4%) in Group 2 [P=0.5]. 2 patients had major bleeds: 1(0.5%) in Group 1 and 1(0.33%) in Group 2 [P=0.69]. There were 30 blood transfusions: 21 (10.5%) in Group 1, 9 (3%) in Group 2 [P<0.0001].

We have demonstrated a reduced requirement for blood transfusions in the tranexamic acid group. However our results, whilst they show a trend towards decreased minor and major bleeding rates, are not significant and require larger studies looking at wound bleeding and leakage.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XLI | Pages 17 - 17
1 Sep 2012
Keenan A Wood A Arthur C Brenkel I
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We set out to demonstrate the 10-year survivorship of the PFC sigma TKA in a young patient group.

Demographic and clinical outcome data were collected prospectively at 6 months, 18 months, 3 years, 5 years and 8–10 years post surgery.

The data were analysed using Kaplan Meier survival statistics with end point being regarded as death or revision for any reason.

203 patients were found to be < 55 years at the time of surgery. Four patients required revision and four patients died. Another four patients moved away from the region and were excluded from the study.

A total of 224 knees in 199 patients (101 male and 98 females.) 168 patients had a diagnosis of Osteoarthritis and 28 with inflammatory arthritis. Average age 50.6 years range 28–55 years (median 51). Ten-year survivorship in terms of revision 98.2% at ten years 95% confidence interval.

Our results demonstrate that the PFC Sigma knee has an excellent survival rate in young patients over the first 10 years. TKR should not be withheld from patients on the basis of age.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXIX | Pages 40 - 40
1 Jul 2012
Arthur C Keenan A Clayton R Brenkel I Walmsley P
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This study reports the first 10-year clinical and radiological follow-up data for the Sigma PFC. The DuPuy Sigma total knee arthroplasty (TKA) is a modification of the well established Press Fit Condylar (PFC) TKA and is used extensively in the UK and worldwide. It is the most commonly used TKA in England and Wales, where it accounts for 34% of all primary TKA.

A total of 235 consecutive Sigma TKAs were performed in 203 patients between October 1998 and October 1999, in our unit. Patients were seen at a specialist nurse led clinic 7 to 10 days before admission and at 6 months, 18 months, 3 years, 5 years and 7-10 years after surgery. Data was recorded prospectively at each clinic visit. Radiographs were obtained at the 5 year and 8-10 year follow-up appointment.

Of 235 knees 171 (147 patients) were alive at 10 years. Twelve were lost to follow up. Nine knees (3.8%) were revised; five for infection and four underwent change of polyethylene insert. Ten-year survival with and end point of revision for any reason was 95.9%, and with and endpoint of revision for aseptic failure was 98.7%. The mean American Knee Society score was 62 at 8-10 years compared with 31 out of 100 pre-operatively. Of 109 radiographs, 47 knees had radiolucent lines but none showed radiological evidence of loosening.

Our results show that the PFC Sigma knee arthroplasty performs well over the first 10 years post implantation.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIII | Pages 12 - 12
1 Jul 2012
Waterson H Brenkel I Cook R
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The Oxford medial unicompartmental knee replacement has been shown to provide good long-tern results in numerous studies with survivorship at 10 years ranging from 82% to 100%. This prospective study describes the survival of 265 Oxford unicompartmental knee replacements implanted in one centre from 1995-2009. 8 were lost to follow up. 40 of the 265 knees were revised. For operation performed from1995-1999 the risk of revision at 5 years was 10%, operations from 2000-2004 the risk of revision was 15% and from 2005-2009 the risk of revision at 5 years was 36%.

This study demonstrates that since 2005 there has been a significant increase in early failure of the Oxford unicompartmental knee at this institution and discusses the possible reasons for this.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXIX | Pages 55 - 55
1 Jul 2012
Ahmed I Maheshwari R Walmsley P Brenkel I
Full Access

Introduction

Revision knee arthroplasty is an increasingly common procedure and can be challenging in the presence of bone defects, ligament instability and soft-tissue deficiencies. Current treatment options in addressing tibial and femoral bone loss in the revision setting include cement, morselised or structural allograft, metal wedges and augments and custom or hinge prosthesis. The aim of this study is to describe our early experience using unique femoral and tibial metaphyseal sleeves as an alternate for dealing with significant tibial and femoral bone loss.

Methods

Porous stepped metaphyseal sleeves were implanted during twenty revision total knee replacements in eleven men and nine women who had an average age of 73.3 years at the time of the procedure. The indications included aseptic loosening in nineteen cases and second stage reimplantation in one case. Bone defects in tibia and femur were classified intra operatively according to AORI classification. All patients were prospectively followed clinically and radiographically for a mean follow up of sixteen months (range 12-26 months).


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXII | Pages 2 - 2
1 Jul 2012
Arthur C Wood A Keenan A Clayton R Walmsley P Brenkel I
Full Access

The DuPuy Sigma total knee arthroplasty (TKA) is a modification of the well-established Press Fit Condylar (PFC) TKA and is used extensively in the UK and worldwide. This study reports the first 10-year clinical and radiological follow-up data for the Sigma PFC.

A total of 235 consecutive Sigma TKAs were performed in 203 patients between October 1998 and October 1999, in our unit. Patients were seen at a specialist nurse-led clinic 1 week before admission and at 6 months, 18 months, 3 years, 5 years and 7-10 years after surgery. Data was recorded prospectively at each clinic visit.

Of 235 knees, 171 (147 patients) were alive at 10 years. Twelve were lost to follow up. Eight knees (3.4%) were revised; four for infection and four underwent isolated change of polyethylene insert. Ten-year survival with an end point of revision for any reason was 95.9%, and with an endpoint of revision for aseptic failure was 98.7%. The mean American Knee Society score was 62 at 8-10 years compared with 31 out of 100 pre-operatively.

Our results show that the PFC Sigma knee arthroplasty performs well over the first 10 years post-implantation.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXII | Pages 18 - 18
1 Jul 2012
Keenan A Arthur C Wood A Jenkins P Walmsley P Brenkel I
Full Access

The aim of this study was to compare the long-term outcome from total knee replacement (TKR) in young versus old patients in terms of pain and functional outcome.

We used our arthroplasty database, which recorded prospectively pain and American Knee Society scores at regular intervals over ten years after TKR. The procedures used a modern, cemented resurfacing type cruciate retaining prosthesis. A cohort of young patients (≤55 years) was identified. A control group of patients ≥ 56 was identified, matching for ASA, body mass index and underlying condition. Change over time was analysed using a factorial repeated measures ANOVA test, which allowed for investigation of difference between groups. 40 Knees in 26 patients were identified. 2 patients died prior to follow up, 2 were revised within the study period (1 for infection at 2 years and one for change of poly at 7 years) and a further 4 were lost to follow up. 7 knees could not be matched and were excluded. This left a study group of 24 young and 24 older knees. Pain scores (p=0.025) and American Knee Society “Knee” (p<0.001) and “Function” (p<0.001) scores changed significantly over time. There were however no statistical differences over the 10-year period in pain (p=0.436) and knee performance (0.618) but overall function was higher throughout the period in the younger group (=0.004).

We conclude that Knee replacement in younger patients produces similar outcomes in terms of pain and function compared with older patients and TKR should not be withheld purely on account of age.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXIX | Pages 109 - 109
1 Jul 2012
Keenan A Walmsley P Arthur C Wood A Jenkins P Brenkel I
Full Access

The aim of this study was to compare the long-term outcome from total knee replacement (TKR) in young versus old patients in terms of pain and functional outcome.

We used our arthroplasty database which recorded prospectively pain and American Knee Society scores at regular intervals over ten years after TKR. The procedures used a modern, cemented resurfacing type cruciate retaining prosthesis. A cohort of young patients (≤55 years) were identified. A control group of patients > 56 was identified, matching for ASA, body mass index and underlying condition. Change over time was analysed using a factorial repeated measures ANOVA test, which allowed for investigation of difference between groups.

40 Knees in 26 patients were identified. 2 patients died prior to follow up, 2 were revised within the study period. (1 for infection at 2 years and one for change of poly at 7 years) and a further 4 were lost to follow up. 7 knees could not be matched and were excluded. This left a study group of 24 young and 24 older knees.

Pain scores (p=0.025) and American Knee Society “Knee” (p<0.001) and “Function” (p<0.001) scores changed significantly over time. There were however no statistical differences over the 10 year period in pain (p=0.436) and knee performance (0.618) but overall function was higher throughout the period in the younger group (=0.004).

Knee replacement in younger patients produces similar outcomes in terms of pain and function compared with older patients and TKR should not be withheld purely on account of age.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXII | Pages 32 - 32
1 Jul 2012
Wood A Smith R Keenan A Sabnis B Walmsley P Brenkel I
Full Access

The risk of venous thrombo-embolism (VTE) is high in orthopaedics. Oral direct factor Xa inhibitors have been introduced to help reduce the incidence of VTE. To reduce post-operative bleeding antifibrinolytics are used. We aimed to ascertain the effect of two drugs on post-operative bleeding and transfusion requirements.

We prospectively recorded patient demographics, operative details, complications, transfusion incidence and VTE incidence in TKR patients. We also sent out a questionnaire to patients asking about wound bleeding and VTE. All patients were given 10mg Rivaroxaban 8 hours post operatively and then once a day for 14 days. Patients given tranexamic acid were given 500mg IV, 5 minutes prior to wound closure at the discretion of the surgeon. VTE was confirmed by Doppler or CTPA as Deep Vein Thrombus or Pulmonary Embolism. Minor bleed was categorised as dressing soakage or reported wound leakage, major bleed as haematoma requiring revision within 30 days.

509 patients underwent TKR: 200(39%) only received Rivaroxaban (Group 1), 296(58%) also received tranexamic acid (Group 2). 13(3%) of patients had no data available. 5 patients had a VTE: 4 (2%) Group 1, 1 (0.3%) Group 2 (P<0.05). 39 patients had a minor bleed: 17 (8.5%) Group 1, 22 (7.4%) Group 2 (P=0.5). 2 patients had major bleeds: 1 (0.5%) Group 1, 1 (0.33%) Group 2 (P=0.69). Blood transfusions 21: (10.5%)Group 1, 9 (3%) Group 2 (P<0.0001).

We have demonstrated a reduced requirement for blood transfusions in the tranexamic acid group. However our results whilst they show a trend towards decrease bleeding rates in both the minor and major bleeds are not significant, requiring larger studies looking at wound bleeding and leakage.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_V | Pages 9 - 9
1 Mar 2012
Sabnis B Dunstan E Ballantyne J Brenkel I
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Rivaroxiban is a factor Xa inhibitor and is a newer oral alternative for thromboprophylaxis after joint replacements. Its major advantage is its oral administration and hence better patient compliance. However there are some doubts about its efficacy compared to dalteparin/heparin. We have recently changed over from using dalteparin injections to rivaroxiban tablets for thromboprophylaxis after hip replacements. We assessed our results to find efficacy and specificity of its action in patients undergoing THR.

504 patients underwent hip replacement in last 2 years. 316 were treated with dalteparin injections (fragmin) for thromboprophylaxis while 189 patients were treated with oral rivaroxiban for 35 days after their hip replacement.

Average haemoglobin drop at 24 hours postop was 2.79 in Rivaroxiban group compared to 3. 10 in dalteparin group. 19 patients (of 189 i.e. 10.05%) required postop blood transfusion in rivaroxiban group as against 60 (of 315 i.e. 19.04%) in Dalteparin group. This difference was statistically significant. Incidence of DVT was no different in either groups, but the number of patients was too small to compare this.

Rivaroxiban appears to be more specific in its action and our results suggest a significant reduction in postop blood transfusion following hip replacements without any increase in rate of Deep Vein Thrombosis. We would like to present our findings and discuss role of oral thromboprophylaxis after joint replacements.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_III | Pages 6 - 6
1 Feb 2012
Amin A Clayton R Patton J Gaston M Cook R Brenkel I
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Aim

To compare the results of total knee replacement in a consecutive series of morbidly obese patients (body mass index (BMI) > 40 kg/m2) with a matched group of non-obese (BMI< 30 kg/m2) patients.

Methods

41 consecutive total knee replacements performed in morbidly obese patients were matched pre-operatively with 41 total knee replacements performed in non-obese patients for age, sex, diagnosis, type of prosthesis, laterality, knee score and function score components of the Knee Society Score (KSS). All patients were prospectively followed up and the post-operative KSS, radiographs, complications (superficial wound infection, deep joint infection, deep venous thrombosis, peri-operative mortality) and five-year survivorship compared for the two groups. No patients were lost to follow-up (mean follow-up in morbidly obese: 38.5 (range 6-66) months; non-obese: 44 (range 6-67) months).


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_III | Pages 118 - 118
1 Feb 2012
Gaston M Amin A Clayton R Brenkel I
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Pre-operative co-morbidities such as known coronary artery disease have commonly deemed a patient at ‘high risk’ for primary elective Total Hip Arthroplasty (THA).

We prospectively collected data on 1744 patients who underwent primary elective THA between 1998 and 2004. 273 had a history of cardiac disease defined as a previous hospital admission with a diagnosis of angina pectoris or myocardial infarction. 594 patients had hypertension defined as that requiring treatment with antihypertensives. We also had data on pre-operative age, sex and body mass index (BMI).

There was no statistically significant increase in early mortality at 3 months with a history of cardiac disease or hypertension and this remained so when adjusting for the other factors in a multivariate analysis. Sex or BMI also did not have a statistically significant effect on the risk of death within 3 months. Increasing age was the only significant risk factor for early mortality (P<0.001).

Longer term mortality at 2 and 5 years in relation to these factors was also examined. Statistical analysis revealed that coronary history now showed a highly significant association (P<0.001) with long term mortality, in patients who survived more than 3 months. 95% confidence intervals for percentage mortality at 5 years were 9.7 - 21.7 with a cardiac history compared to 4.8 - 8.8 without a cardiac history. This remained significant (P=0.002) when adjusted for the other factors. Hypertension continued to have no effect, nor did BMI. Age remained a significant risk factor. Females had a slightly lower long term death rate than males, following THA.

The overall long term mortality following THA was less than expected from the normal population, even in the subgroup with a coronary history.

This study will assist clinicians when advising patients seeking primary elective THA, who have one of these common risk factors.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_III | Pages 20 - 20
1 Feb 2012
Chesney D Sales J Elton R Brenkel I
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Introduction

We report the results of a prospective study of 1349 patients undergoing 1509 total knee replacements, identifying factors increasing the risk of infection.

Methods

Data were collected prospectively between October 1998 and February 2002 by a dedicated audit nurse. Pre-operative demographic and medical details were recorded. Operative and post-operative complications were noted. The definitions of surgical-site infection were based on a modification of those published by the Centre for Disease Control (CDC) in 1992. A superficial wound infection had a purulent discharge or positive culture of organisms from aseptically-aspirated fluid, tissue, or from a swab. Deep infection was counted as an infection that required a secondary procedure. Patients were seen at 6, 18 and 36 months post-operatively in a dedicated knee audit clinic and infection details recorded. The association between infection and other factors was tested by chi-squared or Mann-Whitney tests for categorised or quantitative factors respectively.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_III | Pages 291 - 291
1 Jul 2011
Hunter N Clayton R Brenkel I
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The Depuy Sigma Total Knee Arthroplasty (TKA) was introduced in 1997 as a modification of the Pressed Fit Condylar (PFC) TKA. It is the most commonly used TKA in England and Wales, accounting for 34.9% of all primary TKAs performed in 2006. The PFC has reported 10-year survival rates of 90–95%. This study reports the first clinical and radiological outcomes at 7–9 years following TKA using the PFC Sigma prosthesis.

Three hundred and eighteen consecutive Sigma TKAs were performed in 275 patients between October 1998 and March 2000. Patients were prospectively followed up in a specialist nurse-led clinic. Final review was performed in December 2007 or January 2008, i.e. 7–9 years post surgery. Outcome measures included American Knee Society Scores, Radiographic Scores and Oxford Knee Scores. Survival analysis was performed using the life table method.

Of 318 Sigma knees, 225 (193 patients) were alive at 7–9 years. 6 knees in 5 patients were lost to follow up. 7 knees (2.2%) were revised: 6 for infection within the first two years and 1 at 59 months who underwent isolated change of polyethylene insert. The 9-year survival was 97.7% with revision for any reason as endpoint and 99.6% with revision for aseptic failure as endpoint. The mean American Knee Society Knee score was 84/100 at 7–9 years compared with 33/100 pre-operatively. 0f 140 radiographs, 48 knees had radiolucent lines but no knee showed radiological evidence of loosening.

These results suggest that the Sigma TKA gives excellent clinical results up to 9-years.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_I | Pages 64 - 64
1 Jan 2011
Schmied M Kelly M Ballantyne J Brenkel I
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Hip and knee arthroplasty account for over 95 000 hospital days annually in Scotland. The gross cost of over £81 million can be reduced by £10 million by decreasing length of stay by just one day per patient.

We performed a retrospective analysis of the data from the Scottish Arthroplasty Project (SAP). We specifically looked at length of stay in patients undergoing total hip and knee replacements between 1996 and 2007. We analysed the data on over

91000 total hip and knee replacements. In addition we looked at the influence of age, volume and day of admission on the 2007 data

Over the 11 year period there were significant variations in improved length of stay across the health boards. For the 2007 data, we found that patients treated in boards with high patient volume had shorter hospital stays. Admission policy and age of the patients affected the length of stay it did not account for the large differences between health boards.

The data from the Scottish Arthroplasty Project shows that higher surgical volume correlates with reduced length of stay in arthroplasty patients. The reasons for this are likely to be multifactorial but generalisable and need to be examined more closely with another study.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_I | Pages 41 - 41
1 Jan 2011
Dall G Ohly N Ballantyne J Brenkel I
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Whilst clinical pathways have reduced the length of inpatient stay (LOS) and costs associated with total hip replacement (THR), it would be useful to be able to predict which factors affect the LOS following THR. In this way units could improve patient flow, and thus increase efficiency, by optimising case loads and staffing levels in all related departments. We hypothesised that there were pre-operative factors that will predict the length of inpatient stay following a unilateral primary THR.

Prospective data from 2302 patients who underwent primary unilateral THR for osteoarthritis during a nine-year period from January 01 1998 were included. The relationship between each prospectively recorded factor and LOS was analyzed separately using t-tests or Pearson correlation. Multiple linear regression was used to analyze the effect of each significant factor adjusted for others.

Length of stay varied from 3 to 58 days, with a mean of 8.1 and a median of 7.0. The pre-operative factors that were not significantly associated with the LOS were BMI, Scottish Index of Multiple Deprivation, disabling knee, back or contra-lateral hip pain. A number of pre-operative factors were found to be highly significant predictors of LOS when subjected to univariate analysis, but not significant after multivariate analysis. These were smoking, heart disease, diabetes, pre-operative aspirin, pre-operative haemoglobin and overall Short Form (SF-36) score. Pre-operative factors that were significantly associated with LOS after adjusting for the effect of others were age, sex, pre-operative NSAIDs, consultant surgeon, combined function/activity dimension to Harris hip score, general health perception (GHP) dimension of SF-36, the day of the week and the year of surgery.

Younger age, male sex, higher combined Harris hip function and activity score, higher GHP dimension of SF-36 score and NSAID use are all significantly associated with reduced length of inpatient stay following primary THR for osteoarthritis.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_I | Pages 64 - 65
1 Jan 2011
Cowie J Butler S Brenkel I
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Despite increasing scientific investigation, the best method for preventing post-operative deep vein thrombosis remains unclear in patients undergoing a total hip replacement. In the wake of the recent controversial National Institute for Health and Clinical Excellence Clinical Guidelines on the prevention of thrombo-embolism, we felt it was timely to survey current Scottish Surgeons thrombo-prophylactic practice when performing total hip replacements.

E-mail questionnaires were sent to all Scottish Orthopaedic consultants. They were asked about routine pharmacological and mechanical prophylaxis in patients undergoing total hip replacement. Comparison was made with a previous survey done in 2003.

The response rate was 75%. The survey showed an increased use of pharmacological prophylaxis from 93% to 100%. This was due to the increased use of aspirin, from 51% to 64%. The use of Low molecular weight heparin had remained the same at 51%. No surgeons routinely use Warfarin, low dose heparin or Fondaparinux. Use of graded compression stockings has increased from 59% to 70%.

There is increasing evidence that patients undergoing total hip replacement should receive extended prophylaxis for up to 35 days. This could explain why aspirin is commonly used. Most guidelines, however, do not recommend this drug. With the recent launch of two new oral agents we may see a huge change in prophylaxis in Scotland, as 94% of surgeons said they would use extended prophylaxis if a safe oral agent was found.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_I | Pages 63 - 63
1 Jan 2011
Macpherson G Rewhorn M Brenkel I Dunstan E Ballantyne J
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Our aim was to identify intra-operative and post-operative factors that predict those patients most at risk of dislocation.

Data was prospectively collected on a consecutive series of 2899 total hip replacements undertaken between July 1997 and December 2007. All operations were undertaken in one institution by fourteen orthopaedic consultants. In order to ensure accuracy, our regional database was cross-referenced with the Scottish Arthroplasty Project. Age; sex; BMI; surgeon; surgical approach; monthly caseload per surgeon; and the head size of the implanted prosthesis were analyzed using chi-squared tests for categorised factors and t-tests for quantitative factors.

Of the 2899 patients, 78 (2.7%) were found to have had one or more dislocation. BMI > 35kg/m2 was a significant pre-operative predictor of dislocation (P< 0.001). BMI < 35kg/m2 had a dislocation rate of 2.3% compared with a rate of 6.7% in those > 35kg/m2. Operating surgeon was the only intra-operative factor predictive of dislocation (P< 0.001). Head size was found to be insignificant.

Three surgeons with an overall dislocation rate of < 1% had a dislocation rate of 0.8% for patients with a BMI < 35kg/m2 and 2.0% for BMI > 35kg/m2. In comparison, the remainder of the surgeons had rates of 3.3% for BMI < 35kg/m2 and 9.6% for BMI > 35kg/m2.

Analysis of this consecutive series has shown that a BMI > 35kg/m2 is associated with a significant increase in rates of dislocation. The operating surgeon is also a significant factor and the highest risk is seen in surgeons with a > 1% overall dislocation rate operating on obese patients.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_I | Pages 14 - 14
1 Jan 2011
Smith I Elton R Ballantyne J Brenkel I
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In Scotland, the number of primary total knee replacements (TKRs) performed annually has been steadily increasing. Data from the Scottish Arthroplasty Project has recently demonstrated that the number of knee replacements performed annually has now outstripped the number of hip replacements. The price of the implant is fixed but the length of hospital stay (LOHS) is variable. An understanding of what currently influences LOHS may therefore be of paramount importance in order that we can influence some of these parameters, with resulting benefit to our patients as well as contributing significantly and favourably towards the health economics of this procedure. This study investigates the influence of intra- and post-operative variables on LOHS.

All patients who underwent primary unilateral TKR in the region of Fife, Scotland, United Kingdom, during the period December 1994 to February 2007 were prospectively investigated. The following intra and postoperative details were recorded: length of operation, need for urinary catheterisation, patella resurfacing, lateral release, blood transfusion, the presence of superficial or deep infection, day 1 post-operative haemoglobin and haemoglobin drop (haemoglobin drop between admission haemoglobin and day 1 post-operative haemoglobin). The data was analysed using univariate and multiple linear regression statistical analysis.

Data on LOHS was available from a total of 2105 primary unilateral TKRs. The median LOHS was 8.0 days. The highly significant intra and post-operative factors associated with an increased LOHS were lateral release, post-operative haemoglobin, blood transfusion, urinary catheterisation, deep and superficial infection. An awareness and understanding of these factors may enable us to influence them favourably with resulting reduction in the LOHS and, therefore, the associated costs.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_II | Pages 311 - 311
1 May 2010
Savaridas T Brenkel I Ballantyne J
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Introduction: Total Hip Replacement (THR) is an effective procedure that improves Quality of Life (QoL) in patients with hip arthritis. Co-existing back pain is common in these patients. We assessed the impact of back pain on the medium term outcomes of patients undergoing unilateral THR using a disease specific measure, Harris Hip Score (HHS) and a general health questionnaire, Short Form-36 Health Evaluation (SF-36). The SF-36 generates scores on 8 dimensions of QoL; physical functioning (PF), role limitation due to physical problems (RP), role limitation due to emotional problems (RE), social functioning (SF), mental health (MH), energy/vitality (EV), bodily pain (Pain) and general health perception (GHP). It also contains an item requesting information on perceived health change over the past year (CH).

Methods: Between 4th January 1998 and 22nd July 2001, 909 consecutive patients undergoing unilateral THR were entered into a regional arthroplasty database. An audit nurse collected data prospectively. Patients were assessed pre-operatively and demographic details recorded. Patients were asked specifically about the presence or not of back pain. Post-operative follow up was at 6 mnths, 18 mnths, 3 yrs and 5 yrs. At each point the HHS and SF-36 were measured.

There were more females in our study population (61.2% v 38.8%). Statistical analysis was performed for males and females after adjusting for age, body mass index and pre -op scores.

Results: Pre-op, mean HHS and SF-36 score were lower for patients with back pain. Post-THR, patients had overall better outcome scores. Male patients with back pain had significantly lower (P< 0.01) post-THR outcome scores at all time points for HHS, PF, SF and Pain compared to their male peers without back pain. These changes persisted to 5 yrs. This effect was not demonstrated in female patients. The only exception was in the Pain domain of SF-36 where female patients with back pain had lower scores (P< 0.01) than those without back pain.

Conclusion: Patients with back pain obtain significant benefit from unilateral THR in the medium term and this is maintained at 5 yrs. Despite the clinical benefit to the group as a whole, the absolute scores for males with pre-op back pain remain significantly lower than their peers without back pain. Pre-op back pain did not significantly affect outcome in females.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_II | Pages 306 - 307
1 May 2010
Ohly N Dall G Ballantyne J Brenkel I
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Introduction: Increasingly, clinical pathways and fast-track protocols are reducing hospital in-patient stay following elective joint replacement surgery. In order to improve efficiency in our unit, we undertook a prospective observational study to identify pre–and peri-operative factors associated with increased length of stay.

Methods: From our prospective primary hip arthroplasty database we analysed data from 2678 consecutive patients over a 9-year period from 1998–2007. Patients were excluded who had bilateral hip replacement, died within 30 post-operative days, or had surgery for a diagnosis other than primary osteoarthritis. This left 2302 patients who were analysed using multiple logistic regression analysis

Results: Length of stay varied from 3 to 58 days, with a mean of 8.1 days, and median 7 days. After multivariate analysis, factors that were found to be significantly associated with shorter length of stay were younger age (p< 0.001), male sex (p< 0.001), more recent year of admission (p=0.008), regular non-steroidal anti-inflammatory medication (p< 0.001), lower Harris Hip Score (p< 0.001), and higher General Health Perception dimension score on SF-36 questionnaire (p< 0.001). In addition, the absence of blood transfusion during admission (p< 0.001) and absence of post-operative urinary catheter (p< 0.001) were also associated with shorter length of stay. The following factors, in particular, were not found to be significantly associated with increased length of stay: obesity, diabetes, smoking, medical comorbidity, other disabling joint condition, use of wound drain post-operatively.

Conclusions: We have identified a number of pre-operative factors that predict likely length of stay in a large cohort of patients undergoing primary hip replacement. This data could be used in the future for resource allocation and to improve efficiency in this significant area of healthcare.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_II | Pages 328 - 328
1 May 2010
Smith I Elton R Brenkel I
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Introduction: In Scotland, the number of primary total knee replacements has been steadily increasing since 1992. It has been predicted that the number of total knee replacements performed annually will soon outstrip the number of hip replacements. The price of the implant is fixed but the length of hospital stay, and associated cost, is variable. An understanding of what currently influences length of hospital stay may be of paramount importance in order that we can influence some of these parameters, with resulting benefit to our patients as well as contributing significantly and favourably towards the health economics of this procedure.

Materials and Methods: All patients who underwent primary unilateral total knee replacement in the region of Fife, Scotland, UK, during the period December 1994 to February 2007 were prospectively investigated. The following information was gathered: age, sex, body mass index (BMI), year of operation, day of operation, diagnosis, surgeon grade, consultant performing the operation, walking score, walking aids score, stair score, American Knee Society score (pain, stability and range of motion), length of operation, need for lateral release, patella replacement, urinary catheterisation, blood transfusion, presence of deep or superficial infection, pre and post-operative haemoglobin values, haemoglobin drop, and length of hospital stay. All the data was analysed using univariate and multiple linear regression statistical analysis.

Results: Data on length of hospital stay was available from a total of 2105 unilateral total knee replacements. Length of stay varied from 4 to 70 days, with a mean of 9.4 and a median of 8.0. There were numerous highly significant predictors of increased length of hospital stay, when considered separately. Many of these independently significant factors remained significant when adjusted for the effects of the others. These included age of the patient, year of admission, consultant performing the operation, use of a walking aid, lateral release, deep and superficial infection, pre and post-operative haemoglobin values, urinary catheterisation and blood transfusion. Of note, the day of operation and high BMI did not influence the length of stay.

Conclusion: Prolonged hospital stay following total knee replacement is associated with demographic, preoperative, intra-operative and post-operative factors. An awareness of these factors gives us the opportunity to make attempts to influence them favourably with resulting reduction in length of hospital stay and, therefore, the associated costs.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 56 - 57
1 Mar 2010
Murray D Bush P Brenkel I Hall* A
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Chondrocytes are responsible for the mechanical resilience of cartilage by controlling the synthesis/degradation of the extracellular matrix. In osteoarthritis (OA), increased activity of cytokines/degradative enzymes (e.g. IL-1beta, MMP-13) play a key role leading to matrix breakdown/cartilage loss. Studying early events in OA might identify targets for limiting the deleterious changes to cartilage stability. Human chondrocyte shape in situ is normally elipsoidal/spheroidal however abnormal forms within otherwise macroscopically normal cartilage are present. Changes to cell shape can alter ECM metabolism and thus these abnormal forms might be an early event in OA. We have investigated whether levels of IL-1beta and MMP-13 are altered in human chondrocytes of abnormal morphology.

Tibial plateau cartilage was obtained from patients undergoing knee arthroplasty and only areas graded 0 or 0–1 studied. The shape of fluorescently-labelled in situ chondrocytes was classified by confocal scanning laser microscopy with cartilage depth, and cells characterised as normal (no cytoplasmic processes) or abnormal (one/more cytoplasmic process). Within grade 0 cartilage about 40% of the cells demonstrated abnormal morphology with a reduced proportion in deep zones. Fluorescence immunohistochemistry of antibodies for IL-1beta or MMP-13 was studied in the same cells and quantified. There was an increase in IL-1beta fluorescence with abnormal chondrocytes within the superficial (p=0.033; 21 joints > 190 cells) and deep zones (p=0.001; 8 joints > 100 cells). There were no differences between MMP-13 labelling of normal compared to abnormal chondrocytes within either the superficial or deep zones.

Our results suggest that in relatively non-degenerate cartilage, a proportion of the chondrocyte population demonstrated abnormal morphology and that these cells have elevated levels of IL-1beta but not MMP-13. However, we do not know if chondrocyte shape alters cytokine levels, or vice versa. Additionally, the role of cartilage age is unclear, as although the cartilage samples were relatively normal they were obtained from aged individuals. Nevertheless these results show changes to chondrocyte morphology and increased levels of IL-1beta, and thus presumably matrix catabolism - in relatively normal human articular cartilage, raising the possibility that this is an early event in cartilage degeneration.

Supported by the Wellcome Trust (075753).


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_I | Pages 19 - 19
1 Mar 2009
Rainey G Khan S Brenkel I
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Loss of blood is inevitable during knee replacement surgery, sometimes requiring transfusion. Allogenic blood leads to a risk of disease transmission and immunological reaction. There are various practices used. There is still a risk of bacterial transmission with stored blood and haemolytic transfusion reactions can still occur. Data was collected between 1998 and 2006. There was data on transfusion in 1532 patients undergoing primary knee replacements. There were 1375 unilateral TKRs and 157 bilateral TKRs. After reducing the bilateral cases to one record per patient, it was agreed to restrict the main analysis to 1532 patients. Data was collected prospectively at a pre-admission clinic 3 weeks prior to surgery. Haemoglobin was checked and body demographics including BMI were obtained. Each patient also had a knee score assessed. All patients received a LMWH pre-op until discharge. A tourniquet was used in each case and all patients had a medial para-patellar approach. No drains were used and operation details such as a lateral release were recorded. As per unit protocol, patients with a post-op haemoglobin less than 8.5g/dl were transfused as were symptomatic patients with haemoglobin between 8.5g/dl and 10g/dl. Each of the possible predictive factors was tested for significant association with transfusion using chi-squared or t-tests as appropriate. Multiple logistic regression was used to test for the independent predictive of factors after adjusting for one another. Results show that transfusion was more likely if the patient was older, female, short, light or thin. Among peri-operative factors, the chance of a transfusion was increased for bilateral patients, those with low knee scores and those with high ASA scores. Also patients undergoing a lateral release, those with low pre-op haemoglobin and those with a large post-op drop were more likely to be transfused. All the significant variables were entered into a forward stepwise multiple logistic regression. Transfusion was significantly more likely in those undergoing a bilateral procedure, with a low BMI, low pre-op haemoglobin and those with a large post-op drop (> 3g/dl). Allogenic transfusion is associated with immune-related reactions, from pyrexia to urticaria to haemolytic transfusion reactions, which can be life threatening. There is also the risk of viral pathogen transmission. Women were shown to be almost twice as likely to need transfusion. This has been shown in previous studies and is thought to be due to women having a lower weight and pre-op haemoglobin, both of which were shown to be significant independent factors in increasing the risk of transfusion. A pre-operative haemoglobin of less than 13g/dl, a BMI less than 25, and undergoing a bilateral procedure were shown to have an increased risk of transfusion. For patients falling into these categories, measures can be planned to try and reduce this risk.


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_I | Pages 103 - 103
1 Mar 2009
Gaston M Amin A Clayton R Brenkel I
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Preoperative co-morbidities such as known coronary artery disease have commonly deemed a patient at ‘high risk’ for primary elective Total Hip Arthroplasty (THA). We prospectively collected data on 1744 patients who underwent primary elective THA between 1998 and 2004. 273 had a history of cardiac disease defined as a previous hospital admission with a diagnosis of angina pectoris or myocardial infarction. 594 patients had hypertension defined as that requiring treatment with antihypertensives.

We also had data on preoperative age, sex and body mass index (BMI).

There was no statistically significant increase in early mortality at 3 months with a history of cardiac disease or hypertension and this remained so when adjusting for the other factors in a multivariate analysis. Sex or BMI also did not have a statistically significant effect on the risk of death within 3 months. Increasing age was the only significant risk factor for early mortality (P< 0.001).

Longer term mortality at 2 and 5 years in relation to these factors was also examined. Statistical analysis revealed that coronary history now showed a highly significant association (P< 0.001) with long term mortality, in patients who survived more than 3 months. 95% confidence intervals for percentage mortality at 5 years were 9.7 – 21.7 with a cardiac history compared to 4.8 – 8.8 without a cardiac history. This remained significant (P=0.002) when adjusted for the other factors. Hypertension continued to have no effect, as did BMI. Age remained a significant risk factor. Females had a slightly lower long term death rate than males, following THA.

The overall long term mortality following THA was less than expected from the normal population, even in the subgroup with a coronary history.

This study will assist clinicians when advising patients seeking primary elective THA, who have one of these common risk factors.


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_I | Pages 134 - 134
1 Mar 2009
cowie J Khan L Ballantyne J Brenkel I
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Aim: To study the effect of smoking on the rate of complications and functional outcome after Total Hip Replacement (THR).

Methods: Data was prospectively collected for all patients undergoing a unilateral, primary THR in one hospital during the period 1998 to 2006 Data was collected at pre-operative assessment, in the peri-operative period and at 6 months, 18 months, 3 years and 5 years. Patients were placed in one of three groups; smokers, ex-smokers and those who had never smoked.

Outcome measures included rate of complications: infection, DVT, PE, length of hospital stay and Harris Hip Score (HHS).

Statistical analysis was undertaken to determine any correlation between smoking and these outcome measures using chi-squared tests, t-tests and multiple regression adjusting for confounding factors.

Results: 1765 patients underwent THR during the study period, of whom 635 were males and 1130 females, with a mean age at operation of 69.

268 patients (15%) were smokers, 582 patients (33%) were ex-smokers and 917 patients (52%) had never smoked. As there was little data available on when the ex-smokers had stopped smoking we studied current smokers compared to patients that had never smoked

There were no significant differences in complications such as DVT, PE, Deep infection and Superficial infection, these were all rare events. Neither was there any significant difference in hospital stay times. After adjusting for pre-operative HHS, age, sex and ASA status current smokers had significantly lower HHS at 6 months (p< 0.001, 95% confidence interval for effect size 1.6 to 5.3), and also showed a lower HHS at 18 months, 3 years and 5 years although not significantly so.

Conclusion: Current smokers have a significantly lower HHS post-operatively in comparison to non-smokers. In a health system where more and more patients wish to know the risk associated with potential operative interventions, we can now say that patients who smoke will have a poorer outcome post Total Hip Replacement. This may also allow us to discourage some patients wishing to have THR whom are poor operative candidates.

We plan to further analysis the data to try and ascertain why this is the case.


Introduction: Pharmacological and mechanical methods are recommended to prevent venous thromboembolism (VTE) following hip replacement (THR). However, data on mechanical methods such as graduated compressive stockings (GCS) are limited. This study examined the efficacy and safety of GCS when added to fondaparinux.

Methods: The randomised treatments were 2.5 mg fondaparinux for 5–9 days starting postoperatively alone or with GCS for 42±7 days. The primary efficacy outcome was VTE or sudden death prior to Day 42±7. All patients were to have duplex USS at day 42 + 7. VTE was defined by verified symptomatic VTE or asymptomatic proximal DVT. The main safety outcomes were major and minor bleeding and VTE death.

Results: 856 patients were randomised, of which 799 were THR patients. Of these 756 (95%) were evaluable, 377 in the fondaparinux and 379 in the fondaparinux plus GCS groups. Risk factors for thrombosis were recorded (age > 75 in 20%, history of obesity in 21%, cancer in 6% and VTE in 3%). Compliance with GCS was high, with 85% wearing them continuously. The primary efficacy outcome of VTE or sudden death in THR patients was similar in each treatment group, the results were 5.5% in the fondaparinux only group and 5.3% in the fondaparinux with GCS group; odds ratio was 0.96, 95% confidence interval 0.50–1.83, p=0.91. Outcomes were not different for long-length and short-length stockings. Major bleeding occurred in one patient (< 1%), minor bleeding in 6.7%. No VTE deaths were reported.

Discussion: The addition of GCS to fondaparinux showed no benefit in thromboprophylaxis over fondaparinux alone in this large study of THR patients. Therefore GCS may not be indicated in patients receiving fondaparinux. Graduated compression stockings are time consuming to measure and fit, inconvenient and expensive; therefore we recommend a reconsideration of this current and commonly used practice in THR.


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_I | Pages 168 - 168
1 Mar 2009
Sabnis B Sales J Brenkel I
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Background: Intracapsular neck of femur fracture (# ICNOF) is one of the most common fractures in the elderly. In octa and nonagenarians, with age associated and other co morbidities, achieving a pre injury status of mobility is the deemed result. The physiological age, rather than the chronological one is an important factor determining the type of joint used and results in these patients.

Aim: We present here, a study of 349 patients in the age group of 80 to 100, who underwent hemiarthroplasty as primary treatment for # ICNOF.

Patients and Methods: We studied the data from a prospective hip database of patients undergoing hemiarthroplasty for # ICNOF between Jan 2000 and Jan 2005. All patients admitted with # ICNOF in our centre are assessed by a Hip audit nurse. Pre and post operative data is collected in a specific format. Patients undergo hemi-arthroplasty usually within 24 hours of admission. The type of joint used in decided by the operating surgeon. Patients were reviewed at the 4 month mark after the surgery. They were assessed for pain, mobility and complications. Seven outcomes and eight possible confounding factors were considered and statistical comparison was done to find specific correlation between these factors.

Results: 613 patients underwent hemiarthroplasty during the said period. 349 of these were more than 80 years of age. The mortality and mobility in this group was studied and various factors determining the outcome were assessed and statistical correlation tested. The mortality was expectedly higher in elderly population. Post operative mobility was mainly related to the preoperative functional status. In addition, age, other co-morbidities, ASA grade and joint type also had bearing on the Results:

Discussion: We are a busy District General Hospital in Scotland and hemiarthroplasty for # ICNOF is one of the routinely performed surgeries with more than 100 patients undergoing this procedure in a year. We have a dedicated Hip audit nurse who is responsible for maintaining a database for all these patients.

With increasing age of the population, # ICNOF in over 80s has evolved into a commonly encountered problem. Early mobilisation and aiming for pre injury functional status is an achievable goal in most. ‘The better they walked before, the better they will walk after’ is the golden rule to predict outcome. We use uncemented Austin Moore prosthesis for all patients but prefer to use a bipolar uncemented HAP coated prosthesis (JRI Furlong prosthesis) for patients who are relatively active and independent, regardless their age. The early results in this second group of patients are predictably better, but it will require further detailed study to determine whether these hold true in long term as well.


The Journal of Bone & Joint Surgery British Volume
Vol. 90-B, Issue 11 | Pages 1536 - 1536
1 Nov 2008
COHEN AT SKINNER JA WARWICK D BRENKEL I


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_III | Pages 572 - 572
1 Aug 2008
Rainey G Brenkel I Gilani S Elton R
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As blood transfusion is associated with various risks, a prospective study was carried out to see if it was possible to predict patients more likely to require transfusion following TKR.

Data was collected prospectively on 1532 patients undergoing primary TKR between 1998 and 2006. This was collected at a preadmission clinic and various demographics were measured including haemoglobin, BMI, and a knee score. All patients had a tourniquet and the same approach. All received a LMWH until discharge. Patients with a post op haemoglobin less than 8.5 g/dl were transfused as were those less than 10 g/dl who were symptomatic as per unit protocol.

Each of the predictive factors was tested for significance using t-tests and chi-squared tests as appropriate. Multiple logistic regression was used to test for the independent predictive of factors after adjusting for one another.

Results show transfusion is more likely if the patient was older, female, short light or thin. Also those undergoing a lateral release or a bilateral procedure, having a low pre-op haemoglobin or a large post-op drop were more likely to be transfused. There was also a 2 fold difference between surgeons.

After regression analysis 4 important factors were identified. These were a bilateral procedure, low pre-op haemoglobin, a low BMI or having a post-op drop greater than 3g/dl.

Following this all patients with pre-op haemoglobin less than 11g/dl are postponed and investigated and treated as required. For those with the above predictive factors, measures can be taken to try and reduce the rate of transfusion such as pre-donation, cell salvage or tran-sexamic acid.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_II | Pages 314 - 314
1 Jul 2008
Ng C Ballantyne J Brenkel I
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Introduction: SF-36 is a validated 36-item questionnaire that measures eight dimensions of quality of life(QoL): physical functioning(PF), role physical(RP), role emotional(RE), social functioning(SF), mental health(MH), energy/vitality(EV), bodily pain(Pain) and general health perception(GHP). The primary aim of the study was to evaluate QoL outcomes after total hip replacement(THR) using SF-36.

Methods: From 5/1/1998 until 16/8/2005, we prospectively collected data on 569 patients who had THR in Fife. 30 of them had bilateral THR. Each patient was assessed pre-operatively and was reviewed at 6 months, 18 months, 3 years and 5 years post-operatively. A SF-36 was filled in at each appointment.

Results: During the period, 6 patients died, 4 had revision, 19 were lost to follow-up and 46 did not attend their 5-year review. Subsequently, 494 patients had a 5-year review but 46 of them did not fill in the questionnaire. Analysis was performed on the remaining 448 patients (male=179, female=269).

Mean scores of PF, RP, RE, SF, EV and Pain improved significantly following THR. The improvement remained significant throughout the follow-up (p< 0.0005). MH was the only dimension which did not change significantly after THR. There was a significant decline in GHP (p< 0.0005).

Females reported lower scores in all dimensions apart from GHP. They were also significantly older than the males (66.66±9.41 vs. 64.69±10.27 years; p< 0.037).

Patients who had unilateral or bilateral THR reported similar scores preoperatively and in the initial follow-up. Significant differences were only noted at 3 and 5 years with the bilateral group reported a higher score.

Discussion: THR improved QoL and the benefit was still evident at 5 years post-operatively. However the perception of general health continued to deteriorate, probably due to the effects of aging. More advanced age of females might partly contribute to their lower scores.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 24 - 24
1 Mar 2008
Moran M Walmsley P Gray A Brenkel I
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There is little evidence describing the influence of body mass index on the outcome of Total Hip Replacement (THR). There are concerns that an increasing BMI may lead to increased blood loss, infection and venous thromboembolism. 800 consecutive patients undergoing primary cemented THR were followed for a minimum of 18 months. The Harris Hip Score (HHS) and SF-36 were recorded pre-operatively and at 6 and 18 months post-operatively. In addition other significant events were noted, namely death, dislocation, re-operation, superficial and deep infection and blood loss. Multiple regression analysis was performed to identify whether BMI was an independently significant predictor of the outcome of THR.

No relationship was seen between the BMI of an individual and the development of any of the complications noted. The HHS was seen to increase dramatically post-operatively in all patients. BMI did predict for a lower HHS at 6 and 18 months, and a lower physical functioning component of the SF-36 at 18 months. This effect was small when compared with the overall improvements in these scores.

Conclusion: THR provides good symptomatic relief irrespective of BMI. On the basis of this study we can find no justification for withholding THR solely on the grounds of BMI.


The Journal of Bone & Joint Surgery British Volume
Vol. 89-B, Issue 7 | Pages 887 - 892
1 Jul 2007
Cohen AT Skinner JA Warwick D Brenkel I

Little is known about the efficacy of graduated compression stockings in preventing venous thromboembolism after hip surgery. We conducted a prospective, randomised single-blind study to determine whether the addition of compression stockings to fondaparinux conferred any additional benefit.

The study included 874 patients, of whom 795 could be evaluated (400 in the fondaparinux group and 395 in the fondaparinux plus compression stocking group). Fondaparinux was given post-operatively for five to nine days, either alone or combined with wearing stockings, which were worn for a mean 42 days (35 to 49).

The study outcomes were venous thromboembolism, or sudden death before day 42. Duplex ultrasonography was scheduled within a week of day 42. Safety outcomes were bleeding and death from venous thromboembolism.

The prevalence of deep-vein thrombosis was similar in the two groups 5.5% (22 of 400) in the fondaparinux group and 4.8 (19 of 395) in the fondaparinux plus stocking group (odds ratio 0.88, 95% confidence interval 0.46 to 1.65, p = 0.69). Major bleeding occurred in only one patient.

The addition of graduated compression stockings to fondaparinux appears to offer no additional benefit over the use of fondaparinux alone.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_III | Pages 392 - 392
1 Oct 2006
Huntley J Brenkel I McBirnie J Simpson A Hall A
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Autologous osteochondral cylinder transfer is a treatment option for small articular defects, especially those arising from trauma or osteochondritis dissecans. There are concerns about graft integration and the nature of tissue forming the cartilage-cartilage bridge. Chondrocyte viability at graft and recipient edges is thought to be an important determinant of quality of repair. The aim was to evaluate cell viability at the graft edge from ex vivo human femoral condyles, after harvest using conventional technique. With ethical approval and patient consent, fresh human tissue was obtained at total knee arthroplasty. Osteochondral plugs were harvested using the commercially available Acufex 4.5mm diameter mosaicplasty osteotome from regions of the lateral femoral condyle (anterior cut) that were macroscopically non-degenerate and microscopically non-fibrillated. Plugs were assessed for chondrocyte viability at the graft edge using confocal laser scanning microscopy (CLSM), fluorescent indicators and image analysis. The central portions of the plugs remained healthy, with > 99% cell viability (n=5). However, there was substantial marginal cell death, of thickness 382 ± 68.2 microm in the superficial zone (SZ). Demi-plugs were created by splitting the mosaicplasty explants with a fresh No. 11 scalpel blade. The margin of SZ cell death was 390.3 ± 18.8 microm at the curved edge of the Acufex, significantly (Mann-Whitney; P= 0.0286; n =4) greater than that at the scalpel cut (34.8 ± 3.2 microm). Findings were similar when the cartilage was breached but the bone left intact. In time-course experiments, the SZ marginal zone of cell death after Acufex harvest showed no increase over the time period 15 minutes to 2 hours. Mathematical modelling of the mosaicplasty surface shows that cell death of this magnitude results in a disturbing 33% of the superficial graft area being non-viable. In conclusion, mosaicplasty, though capable of transposing viable hyaline cartilage, is associated with an extensive margin of cell death that is likely to compromise lateral integration. There would appear to be considerable scope for improvement of osteochondral transplant techniques which may improve graft-recipient healing and clinical outcomes.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_II | Pages 253 - 253
1 May 2006
Clayton R Amin A Gaston M Brenkel I
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Introduction: The Depuy Pressed Fit Condylar (PFC) total knee arthroplasty (TKA) is well established with reported 10-year survival rates of 93–97%. The PFC was modified, leading to the introduction of the Sigma TKA in 1997. The theoretical advantages of the Sigma system include increased contact area between the femoral component and the tibial insert. We report the first 5-year clinical and radiographic follow-up data for the Sigma TKA.

Methods: Over a ten-month period, 211 Sigma TKAs were performed in 179 patients. Patients were seen at a specialist nurse-led clinic at admission and at 6 months, 18 months, 3 years and 5 years after surgery. Data were recorded prospectively at each visit. Radiographs were obtained at the 5-year follow-up appointment.

Results: Of 211 knees, 187 (150 patients) were alive at 5 years. 5 were lost to follow up. 5 knees (2.4%) were revised: 4 for infection and 1 underwent change of polyethylene insert at 4.9 years. 5-year survival with an endpoint of revision for any reason was 97.4%; with an endpoint of revision for aseptic loosening it was 99.5%. The median American Knee Society score was 93/100 at 5 years compared with 25/100 at admission. Of 145 radiographs, 17 (11.7%) showed radiolucent lines. None showed radiographic loosening of either component. 28 (19.3%) had alignment outside the range of 7±3° valgus.

Discussion: These results suggest that the Sigma TKA gives excellent clinical results after five years. Further follow-up studies are required to see if this performance is maintained in the long term.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_I | Pages 39 - 39
1 Mar 2006
Chan P Brenkel I Aderinto J
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An analysis on prospective data collected on our hip database was carried out on all patients undergoing primary cemented unilateral total hip arthroplasty in the last 5 years comparing the short term outcomes between diabetics and non-diabetics. There were 1220 non-diabetics and 77 diabetics identified from the database with at least 3 years follow up. (average 3.6 years). We found no significant difference with respect to age, sex and diagnosis between the 2 groups. Diabetics did have a significantly higher BMI (30.2 versus 27.7, p< 0.001) and higher incidence of coronary artery disease (31% versus 15%, p< 0.001) We found no increase in the rate of deep periprosthetic infection, superficial wound complications, dislocation, blood loss and DVT between diabetics and non-diabetics even after adjusting for potential confounders of age, sex, diagnosis, BMI and the presence of coronary artery disease. The only factor that was found to be significantly different between the 2 groups was length of stay (10.73 versus 9.56 days, p< 0.05). Further analysis of the diabetic group only showed no difference with regard the same outcomes between insulin-dependent, diet-controlled and diet and oral hypoglycaemic-controlled patient subsets. From this study we conclude that at the time of taking informed consent from diabetic patients undergoing total hip arthroplasty the only potential difference from non-diabetics is that the length of stay may be longer.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_I | Pages 100 - 100
1 Mar 2006
Amin A Patton J Cook R Gaston M Brenkel I
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Introduction To assess five-year survivorship and clinical outcome following unicompartmental knee replacement (UKR) and total knee replacement (TKR) in pre-operatively matched patient groups.

Methods From a prospective database of over 600 patients undergoing knee replacement for osteoarthritis, 70 primary Oxford UKRs (62 patients) were matched pre-operatively with 70 primary PFC TKRs (68 patients) for age, sex, body mass index, knee range of movement and Knee Society Score (KSS). The two groups were assessed at six, eighteen, thirty-six and sixty months following knee replacement and compared for survivorship of the prosthesis (with failure defined as revision for any reason or ‘worst-case’ assuming all patients lost to follow up are revised), post-operative ROM achieved and clinical outcome based on the KSS (reported as separate knee and function score).

Results Three (5 percent) patients in the UKR group and two (3 percent) in the TKR group were unavailable for follow-up at five years. Five-year survivorship based on revision for any reason was 90 percent (95 percent Confidence Interval (CI): 82 to 98) for UKR and 100 percent (95 percent CI: 100 to 100) for TKR (log rank test: p=0.009). The ‘worst-case’ five-year survivorship (assuming all patients lost to follow up are revised) was 85 percent (95 percent CI: 76 to 94) for UKR and 97 percent (95 percent CI: 93 to 100) for TKR (log rank test: p=0.02). The mean post-operative ROM achieved was 105.3 degrees following UKR and 98.3 degrees following TKR (difference 7.0 (95 percent CI 3.3 to 10.6), p< 0.001). There was no difference in the KSS between the two groups for the knee score (difference 0.1 (95 percent CI: −4.3 to 4.5), p=0.9) and function score (difference 2.6 (95 percent CI: −1.7 to 6.9), p=0.2).

Conclusion In comparable patients with osteoarthritis of the knee, survivorship remains superior for TKR at five years. The ROM achieved is greater for UKR but there is no difference in the overall clinical outcome following UKR or TKR. We believe that UKR should only be performed in carefully selected cases because mid-term clinical outcome is similar following UKR or TKR and the complication rate may be higher for UKR.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_I | Pages 28 - 28
1 Mar 2006
Elson D Brenkel I
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Introduction: Pain is one of the most important outcome measures that contributes to patient dissatisfaction following total knee arthroplasty (TKA) and unexplained pain poses a difficult problem to manage. This paper focuses on a group of patients with unexplained knee pain post arthroplasty to identify any predictors of a poor pain outcome.

Methods: A prospective study of 622 primary TKAs performed on 512 patients using cemented press fit condylar prosthesis was the basis to examine a group of patients that reported moderate or severe pain at 5 years. Demographic and operative variables as well as American Knee Society Scores were collected prospectively. Data was available for 462 knees at 5 years. After exclusion of patients with mild pain, two groups were generated; 374 with no pain and 28 with moderate or severe unexplained pain. Univariate linear analysis was performed to identify possible predictors of poor outcome and this was further refined using multiple regression analysis to remove the effect of confounding factors.

Results: Comparison of the pain and no pain group found the following to be significant predictors of poor outcome: Staged approach to bilateral disease when compared to simultaneous bilateral surgery (13% vs 2%, P< 0.01), age below 60 (17% vs 7%, P< 0.01) and performing lateral release (13% vs 5%, P< 0.01). Other factors which had no predictive effect were gender, body mass index, operating surgeon, patella component, instability and range of motion.

Conclusions: Avoiding surgery in patients aged below 60 and performing simultaneous bilateral TKA instead of a staged approach to bilateral disease, should aid selection of patients for improved outcome in terms of pain. Good surgical technique to avoid lateral release is also recommended to improve outcome.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_I | Pages 89 - 89
1 Mar 2006
Amin A Patton J Cook R Brenkel I
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Aim To compare clinical outcome and complication rates in obese and non-obese patients five years following primary Total Knee Replacement (TKR) for osteoarthritis.

Methods 328 primary TKRs (283 patients) performed between 1995–1999 at a single institution, were followed up prospectively at intervals of 6, 18, 36 and 60 months following surgery and the clinical outcome based on the Knee Society Clinical rating system (subdivided into a Knee Score (KS) and Function score (FS)) recorded at each follow-up interval. The following complications were also recorded: peri-operative mortality, superficial wound infection, deep wound infection, deep vein thrombosis, and revision rate. Three separate comparisons were undertaken by subdividing the study sample into two sub-groups: (1) Group A comprised two subgroups based on body mass index (BMI) – Non-obese (BMI 15–30, 181 TKRs) or Obese (BMI> 30, 147 TKRs). (2) Group B comprised only female patients divided into two sub-groups based on BMI – ‘Non-obese females’ (BMI 15–30, 84 TKRs) or Obese females (BMI> 30, 87 TKRs). (3) Group C comprised two sub-groups based on body weight alone – weight < 100kg (300 TKRs) or weight > 100kg (28 TKRs). A repeated measures split-plot analysis of variance (SPANOVA) was used to evaluate the difference in the clinical outcome at five years between the sub-groups in Group A, B and C. The complication rates were also compared.

Results There was no significant difference in the KS at five years between sub-groups in Group A (p=0.2), B (p=0.2) or C (p=0.3). There was a statistically significant difference in the FS between the subgroups in Group A (p=0.01) and B (p=0.02) but the effect size (relative magnitude of the difference between means) was small (partial eta squared = 0.02 and 0.03, for Group A and B respectively). There was no significant difference in the FS between sub-groups in Group C (p=0.5). There was no significant difference in the complication rate between the sub-groups in Group A, B or C (p> 0.2 for all complications).

Conclusion Obesity does not influence clinical outcome, peri-operative mortality and complication rates five years following TKR. Further studies are required to determine the long-term success of TKR in obese patients.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_I | Pages 48 - 48
1 Mar 2006
Gray A Walmsley P Moran M Brenkel I
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This prospective study aimed to establish if octogenarians undergoing primary hip arthroplasty experienced a similar clinical outcome and complication rate as younger patients.

A total of 585 patients were recruited over a 4-year period. Patients aged 70–79 years and 80–89 years (octogenarians) were placed into separate groups.

Harris hip and SF-36 scores were obtained before and at 6 and 18 months following surgery. Other measurements included: blood loss; blood transfusion rate; wound infection; thromboembolism; dislocation and 90-day mortality.

Statistical analysis included a two-sample t-test and chi-squared analysis with Yates correction to compare results in each group. Analysis of covariance was used to calculate confidence limits for the effect of age group on Harris hip and SF-36 scores at 6 and 18 months after adjusting for levels recorded prior to surgery. Multiple logistic regression analysis was performed to determine any predictive factors for a noted difference in blood transfusion rates between patient cohorts.

A significantly better (P=0.019) improvement in mean Harris Hip score (SD) was seen 18-months after surgery in the younger cohort (43.4 (13.8) compared to 39.8 (10.6)). Length of hospital stay was longer (P< 0.001) in the octogenarians (12.9 (SD 7.0) days versus 10.1 (SD 4.7)) with a higher blood transfusion rate of 40% compared to 28% (P = 0.009). Lower pre-operative haemoglobin levels strongly correlated with the need for blood transfusion. No significant differences in infection, dislocation, thromboembolism or 90-day mortality rates were found.

Conclusions: Octogenarians are more likely to require blood transfusion and a longer hospital stay, with less improvement in clinical outcome at 18 months after primary hip arthroplasty.


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 10 | Pages 1397 - 1401
1 Oct 2005
Walmsley PJ Kelly MB Hill RMF Brenkel I

The routine use of surgical drains in total hip arthroplasty remains controversial. They have not been shown to decrease the rate of wound infection significantly and can provide a retrograde route for it. Their use does not reduce the size or incidence of post-operative wound haematomas. This prospective, randomised study was designed to evaluate the role of drains in routine total hip arthroplasty.

We investigated 552 patients (577 hips) undergoing unilateral or bilateral total hip arthroplasty who had been randomised to either having a drain for 24 hours or not having a drain. All patients followed standardised pre-, intra-, and post-operative regimes and were independently assessed using the Harris hip score before operation and at six, 18 and 36 months follow-up.

The rate of superficial and deep infection was 2.9% and 0.4%, respectively, in the drained group and 4.8% and 0.7%, respectively in the undrained group. One patient in the undrained group had a haematoma which did not require drainage or transfusion. The rate of transfusion after operation in the drained group was significantly higher than for undrained procedures (p < 0.042). The use of a drain did not influence the post-operative levels of haemoglobin, the revision rates, Harris hip scores, the length of hospital stay or the incidence of thromboembolism. We conclude that drains provide no clear advantage at total hip arthroplasty, represent an additional cost, and expose patients to a higher risk of transfusion.


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 10 | Pages 1446 - 1446
1 Oct 2005
BRENKEL I


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 301 - 302
1 Sep 2005
Walmsley P Cook R Brenkel I
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Introduction and Aims: Venous Thromboembolism is a common complication following a hip replacement. Recently the pulmonary embolism prevention study was published. It reported that aspirin decreased the fatal pulmonary embolism rate in patients admitted with a fracture neck of femur. In addition, new products (synthetic factor X inhibitor-Fondaparinux, and a direct thrombin inhibiter-Desirudin) have been reported to be more effective than low molecular weight heparin in preventing asymptomatic deep vein thrombosis. We felt it was important to repeat a survey, done in 1997, on the use of thromboembolism prophylaxis among British Orthopaedic Surgeons.

Method: A single page questionnaire was sent out to all 1308 consultants – orthopaedic surgeons who were members of the British Orthopaedic Association. Those who did not respond were sent a reminder letter.

Results: We achieved a 72% response rate. All surgeons use some form of prophylaxis. Eighty-five percent of surgeons use pharmacological prophylaxis. Low molecular weight heparin is used by 55% of surgeons. Twenty percent of surgeons use aspirin as their only form of pharmacological prophylaxis. Less than 1% (five consultants) use early mobilisation alone and nearly 2% (13 consultants) use graded stockings and early mobilisation as their only form of prophylaxis. Seventy-four percent of surgeons have a unit policy. Thirty percent have changed their regime in the last three years.

Conclusion: The majority of British orthopaedic surgeons still use pharmacological thromboprophylaxis. There has been a significant increase in the use of Aspirin, from 5% to 30%. Aspirin is often combined with a mechanical prophylaxis. This has led to an increase in the use of intermittent calf compression (3% to 22%), and foot pumps (12% to 19%). Low molecular weight heparin use has fallen by 10%.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 277 - 278
1 Sep 2005
Aderinto J Brenkel I
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The identification of preoperative risk factors for blood transfusion following total joint arthroplasty facilitates the selection of patients for blood-conservation strategies such as preoperative autologous blood donation. We reviewed prospective data on 1016 unilateral THRs to establish the preoperative risk factors associated with peri-operative blood transfusion.

On average, transfused patients were older, with lower preoperative haemoglobin, weight, height and body mass indices than patients who were not transfused. When the relationship between variables and transfusion was examined by multivariate analysis with multiple logistic regressions, only preoperative haemoglobin and weight were identified as significant independent factors increasing the risk of transfusion (p < 0.001). A threefold increase in transfusion risk was associated with haemoglobin below 12.

Patients of low weight or with haemoglobin below 12 should be considered for blood-conserving interventions.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 278 - 278
1 Sep 2005
Ballantyne A Brenkel I
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In consecutive patients undergoing unilateral TKA in a single institution, we undertook an audit of blood transfusion practices before and after introduction of a blood transfusion protocol.

Before and after the introduction of the protocol, 393 patients (group I) and 295 patients (group II) respectively were audited. The protocol stated that only patients with preoperative haemoglobin of less than 11 were cross-matched before surgery. The criterion for postoperative transfusion was a postoperative haemoglobin of less than 8.5 or a symptomatic patient with a haemoglobin greater than 8.5. The introduction of the protocol reduced the transfusion rates from 31% in group I to 11.9% in group II (CI 13.1% to 24.9%). The length of stay was reduced from 11.4 to 9.3 days (CI 1.4 to 2.9).

There were no adverse outcomes related to the introduction of the protocol.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 277 - 277
1 Sep 2005
Brenkel I Cook R
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Venous thrombo-embolism is a common complication following hip replacement. The recently-published pulmonary embolism prevention study reported that aspirin decreased the fatal pulmonary embolism rate in patients with femoral neck fractures. In addition, new products (synthetic factor X-inhibitor Fondaparinux and direct thrombin-inhibiter Desirudin) have been reported to be more effective than low-molecular-weight heparin in preventing asymptomatic DVT. We thought it important to update the 1997 survey on thrombo-embolism prophylaxis by British Orthopaedic Surgeons.

A single page questionnaire was sent to 1308 members of the British Orthopaedic Association who are consultant orthopaedic surgeons. Those who did not respond received a reminder. We had a 72% response rate.

All surgeons use some form of prophylaxis, with 85% using pharmacological agents. Low-molecular-weight heparin is used by 55% of surgeons, while 20% use only aspirin. Fewer than 1% (five consultants) use early mobilisation and nearly 2% (13 consultants) use graded stockings and early mobilisation as their only prophylactic measures. Unit policies govern 74% of surgeons. In the last 3 years, 30% have changed their regime.

Most British orthopaedic surgeons still use pharmacological thromboprophylaxis. The use of aspirin has increased from 5% to 30%. Aspirin is often combined with a mechanical prophylactic. The use of intermittent calf compression has increased from 3% to 22% and of foot pumps from 12% to 19%. The use of low-molecular-weight heparin has fallen by 10%.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 280 - 280
1 Sep 2005
Murray A Brenkel I
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Previous studies have suggested that bilateral TKR is a safe and economically advantageous procedure. However, because of persistent concerns about complications and patients’ ability to rehabilitate, it has not yet become routine practice.

Using data from the Scottish Arthroplasty Project, which has centrally collated data gathered prospectively between 1989 and 1999, we analysed 19 247 patients who underwent primary knee replacement. Any subsequent admission for TKR was noted. Deaths following an index procedure were identified from the General Register of Deaths.

In 30% of patients a contralateral TKR was done within 5 years. The overall hospital stay for both unilateral and bilateral TKR has been comparable since 1993. The mortality rate following simultaneous bilateral TKR (1%) is similar to that following unilateral TKR (1.2%).

Only 25% of Scottish Surgeons perform simultaneous bilateral TKR. However, bilateral knee arthritis is common and bilateral TKR carries no significantly increased cumulative risk of death, deep infection or need for revision. The increased likelihood of blood transfusion should be offset against the definite advantages of one anaesthetic, a reduced hospital stay and good early outcome.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 343 - 343
1 Sep 2005
Patton J Amin A Gaston M Cook R Brenkel I
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Introduction and Aims: Several non-comparative studies for uni-compartmental knee replacement (UKR) and total knee replacement (TKR) have been published, but few provide a direct comparison in well-matched patients. The aim of this study was to assess five-year survivorship and the quality of outcome following UKR and TKR in pre-operatively matched patient groups.

Method: From a prospective database of over 600 patients undergoing knee replacement for osteoarthritis, 70 primary medial Oxford UKRs (62 patients) were matched pre-operatively with 70 primary Kinematic TKRs (68 patients) for age, sex, body mass index, active range of movement (ROM) and Knee Society Score (KSS). The two groups were assessed at six, 18, 36 and 60 months following knee replacement and compared for survivorship of the prosthesis (with failure defined as revision for any reason or ‘worst-case’ assuming all patients lost to follow-up are revised), quality of outcome based on the KSS (reported as separate knee and function score) and the ROM achieved.

Results: Three (4%) patients in the UKR group and two (3%) in the TKR group were unavailable for follow-up at five years. Five-year survivorship (Kaplan-Meier methodology) was significantly different for the two groups using revision for any reason as an endpoint – 90% for UKR, 100% for TKR (log-rank test, p=0.01). Assuming all patients lost to follow-up were revised, the ‘worst-case’ five-year survivorship was also significantly different for the two groups – 85% for UKR, 97% for TKR (log-rank test, p=0.02). Analysis of the KSS at six, 18, 36 and 60 months showed no significant difference between the two groups for the knee score (p=0.48) and the function score (p=0.1). The ROM achieved at five years was greater for the UKR group and the difference was statistically significant (UKR: Least square mean 105 degrees, standard error 1.2; TKR: Least square mean 98 degrees, standard error 1.2, p< 0.001).

Conclusion: In comparable patients with osteoarthritis of the knee, survivorship remains superior for TKR at five years. The ROM achieved is greater for UKR, but there is no difference in the overall quality of outcome following UKR or TKR. We believe that UKR should only be performed in carefully selected cases because mid-term functional outcome is similar following UKR or TKR and the complication rate may be higher for UKR.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_II | Pages 155 - 155
1 Apr 2005
Walmsley P Gray A Moran M Brenkel I
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Aim: To assess the results of total knee arthroplasty in a cohort of patients aged 80–89 years and compare them to a similar group of patients aged 70–79

Introduction: With the average age of the population steadily rising, more patients are likely to present with arthritis over 80 years of age. The benefits of Total Knee Arthroplasty (TKA) in the treatment of osteoarthritis are widely known, but there are few studies which examine the results of TKA in octogenarians.

Methods: Data was collected prospectively from 1995–2002 on 115 patients undergoing TKA aged 80–89 years and compared to 411 patients who were aged 70–79 undergoing TKA during the same period. Patients undergoing unicompartmental, revision or bilateral TKA were excluded. Patients were seen pre-operatively and scores for SF-36, American Knee Society (AKS) score and haemoglobin were taken along with demographic data. The outcome measurements used were SF-36 score, AKS score, blood loss, length of stay, mortality and post-operative complications. These were collected during the first week post-surgery and at 6 and 18 months post-surgery.

Results: Both groups showed significant increases in AKS score at 6 months, (54.17 and 54.45, both p=0.0001). We continued to see improvement of the AKS score up to 18 months (mean 85.38 and 85.12, p= 0.55) with no significant difference between the two groups. Patients over 80 had lower pre-op Haemoglobin (Hb) (mean 13.56 and 12.23, p=0.0001) but experienced the same Hb drop post-procedure. There was no difference in postoperative complications, but the length of stay (8.3 days and 13.9 days, p=0.0001) and mortality rate (0.7% and 5%, p=0.0001) were higher.

Conclusions: Our early results show that TKA can be beneficial to patients over 80 years in terms of mobility and independence, but they have a longer in-patient hospital stay and attract a slightly higher mortality risk at 90 days.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_I | Pages 45 - 45
1 Mar 2005
Hannah H Gaston M Brenkel I
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Introduction: Previous studies have suggested that bilateral total hip replacement (THR) is a safe and economically advantageous procedure. It has not become routine practice in many centres due to persisting concerns about complications and the patients’ ability to rehabilitate. In this study we compare one group of patients who underwent bilateral THR with another group who had only a unilateral procedure despite osteoarthritis in both hips. They were assessed for complications and functional outcome.

Methods: All data collected prospectively between 1998 and 2002. All patients had osteoarthritis and were recruited during the same time period . Group A comprised 49 patients who were listed for bilateral THR. Group B consisted of 215 patients listed for unilateral THR, with both hips symptomatic. Pain and function were assessed using the Harris Hip Score preoperatively and at 6 months post operatively. All intra and postoperative complications were recorded.

Results: There was no statistical difference between the groups for sex , pathology, body mass index or American Society of Anaesthetists (ASA) scores.

There is a difference in age between the two groups with the bilateral group being younger (p< 0.01).

Although group A had a higher death rate, it was not statistically significant. The deep infection and revision rate was similar for both groups. The average length of stay for group A was 13 days compared to 8 days for group B.There was a significant difference in the likelihood of blood transfusion with a transfusion rate of 78% in group A and 22% in group B (p< 0.001).

Conclusion: This study has demonstrated no significant increased risk of death, deep infection or need for revision with bilateral hip replacements. The increased likelihood of blood transfusion should be offset against the definite economic advantages and the good early outcome from performing bilateral total hip replacements.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_I | Pages 75 - 75
1 Jan 2004
Gray A Walmsley P Moran M Brenkel I
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Background: Previous studies have reported mixed findings with regards to post operative complication rates and overall outcome in elderly patients undergoing total hip arthroplasty. The aim of this study was a prospective comparison of physical and functional outcome measurements following primary hip arthroplasty in patients aged 80–90 years to those aged 70–79.

Methods: Data was prospectively recorded from 1998–2002. 144 patients aged 80–90 years underwent primary hip arthroplasty compared to 441 aged 70–79. A pre-operative Harris Hip Score was obtained on all patients and a standardized follow up regimen was used for assessment at 6, 18 and 36 months post surgery. Data collection included: intraoperative blood loss; post operative transfusion rate; incidence of wound infection, DVT and pulmonary embolus; dislocation and mortality rates. Statistical analysis involved two-sample t-test and chi-squared with Yates correction.

Results: Pre-operative Harris Hip Scores were 41.6 (SD 11.2) in the younger cohort and 39.3 (SD 12.4) in the octogenarian (P = 0.04). This score had improved by 39.3 and 38.1 points respectively (P = 0.5) at 6 months; 42.3 and 37.7 at 18 months (P = 0.02); 43.4 and 39.8 at 36 months (P = 0.24).

The mortality rate at 3 months following surgery was 4% in our octogenarian group compared to 1% (P=0.02). Mean length of hospital stay was significantly (P< 0.001) longer at 12.9 (SD 7.0) days compared to 10.1 (SD 4.7). The transfusion rate in our octogenarian group was 40% compared to 28% (P = 0.009). The incidence of deep infection was 1.4% in the older group compared to 0.5% (NS). Each group had a dislocation rate of 1%. and an incidence of DVT and pulmonary embolus that was comparable.

Discussion: Total hip arthroplasty can be performed safely in octogenarians with excellent relief of pain and improved function.


Orthopaedic Proceedings
Vol. 85-B, Issue SUPP_II | Pages 104 - 104
1 Feb 2003
Hill RMF Brenkel I
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Although drains date back to the Hippocratic era, their routine use remains controversial in total hip arthroplasty. The literature suggests that they can provide a retrograde route for infection as well as decreasing the organism count required to develop an infection. The use of drains has not decreased the size of wound haematomas at day five on ultrasound or the incidence of massive wound haematomas. Neither have they been shown to significantly decrease wound infections. This consecutive prospective randomised study was designed to evaluate what role drains have in the management of patients undergoing hip arthroplasty.

A total of 577 patients undergoing unilateral or bilateral hip arthroplasty were evaluated in a randomised prospective trial of drain versus no drain, between September 1997 and December 2000. All patients had a standardised pre, inter and post operative regime and were independently assessed using the Harris hip score and SF36 pre-operatively, at discharge and at six months post surgery.

The superficial and deep infection rate of 6. 4% and 0. 4% was seen in those drained and 7. 1% and 0. 7% in the non-drained group. Only one patient sustained a clinical haematoma that did not requiring drainage or transfusion in the non-drain group. The transfusion rate in those drained was 33. 0% compared to 26. 4% in those not drained. There was no statistical advantage in using a drain P> 0. 05 regarding these variables or in the length of stay, SF36 or Harris hip scores at pre-op and six months. Using a drain did significantly increase the likelihood of requiring a transfusion P< 0. 05.

In conclusion drains provide no statistical advantage whilst represent an additional cost and expose hip arthroplasty patients to an unacceptable risk of infection and transfusion.


The Journal of Bone & Joint Surgery British Volume
Vol. 71-B, Issue 2 | Pages 307 - 310
1 Mar 1989
Dias J Brenkel I Finlay D

Eighty-two of 85 patients who had sustained a fracture of the waist of the scaphoid in 1985 were reviewed more than one year after injury. The incidence of nonunion, defined as a clear gap at the fracture site one year after injury, was 12.3%. This was much higher than expected. Most of the patients with nonunion had symptoms and had appreciable restriction of wrist movement. In a further 25% of the patients at review, the site of the fracture could be easily identified although it appeared to have healed. These patients were older and more of them were women. Three-quarters of these patients had symptoms but their wrist movement was essentially normal.


The Journal of Bone & Joint Surgery British Volume
Vol. 71-B, Issue 1 | Pages 33 - 38
1 Jan 1989
Brenkel I Dias J Davies T Iqbal S Gregg P

In 15 consecutive patients with slipped capital femoral epiphysis we recorded height, weight and skeletal maturity. Sexual maturity was assessed clinically and biochemically, and Harris's hypothesis that there is an increased ratio of serum growth hormone to oestrogen was tested in comparison with 15 age and sex matched controls. We found no difference in skeletal or sexual maturity between the groups, or any overt endocrine abnormality in the patients. However almost half the patients with slipped epiphysis were over the 90th weight percentile, suggesting that mechanical factors such as obesity are more important aetiologically than endocrine abnormalities.


The Journal of Bone & Joint Surgery British Volume
Vol. 70-B, Issue 2 | Pages 299 - 301
1 Mar 1988
Dias J Taylor M Thompson J Brenkel I Gregg P

Inter-observer agreement and reproducibility of opinion were assessed for the radiographic diagnosis of union of scaphoid fractures on films taken 12 weeks after injury. Weighted kappa statistics were used to compare the opinions of eight senior observers reviewing 20 sets of good quality radiographs on two occasions separated by two months. There was poor agreement on whether trabeculae crossed the fracture line, whether there was sclerosis at or near the fracture and on whether the proximal part of the scaphoid was avascular. As a consequence, agreement on union also was poor; it appears that radiographs taken 12 weeks after a scaphoid fracture do not provide reliable and reproducible evidence of healing.


The Journal of Bone & Joint Surgery British Volume
Vol. 70-B, Issue 2 | Pages 247 - 250
1 Mar 1988
Lowrie I Finlay D Brenkel I Gregg P

Thirty-six patients with 39 fresh fractures of the calcaneus were investigated by standard radiography and by computerised tomography. It was found that the size and disposition of the fracture fragments and the degree of involvement of the posterior facet of the subtalar joint were more clearly shown by CT scanning. We recommend this technique for assessment and particularly for pre-operative planning.