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Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_7 | Pages 21 - 21
8 May 2024
Chen P Ng N Mackenzie S Nicholson J Amin A
Full Access

Background

Undisplaced Lisfranc-type injuries are subtle but potentially unstable fracture-dislocations with little known about the natural history. These injuries are often initially managed conservatively due to lack of initial displacement and uncertainty regarding subsequent instability at the tarsometatarsal joints (TMTJ). The aim of this study was to determine the secondary displacement rate and the need for delayed operative intervention in undisplaced Lisfranc injuries that were managed conservatively at initial presentation.

Methods

Over a 6-year period (2011 to 2017), we identified 24 consecutive patients presenting to a university teaching hospital with a diagnosis of an undisplaced Lisfranc-type injury that was initially managed conservatively. Pre-operative radiographs were reviewed to confirm the undisplaced nature of the injury (defined as a diastasis< 2mm at the second TMTJ). The presence of a ‘fleck’ sign (small bony avulsion of the second metatarsal) was also noted. Electronic patient records and sequential imaging (plain radiographs/CT/MRI) were scrutinized for demographics, mechanism of injury and eventual outcome.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_4 | Pages 1 - 1
8 Feb 2024
Gunia DM Pethers D Mackenzie N Stark A Jones B
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NICE Guidelines suggest patients should be offered a Total Hip Replacement (THR) rather than Hemiarthroplasty for a displaced intracapsular hip fracture. We investigated outcomes of patients aged 40–65 who received a THR or Hemiarthroplasty following a traumatic intracapsular hip fracture and had either high-risk (Group 1) or low-risk (Group 2) alcohol consumption (>14 or <14 units/week respectively).

This was a retrospective study (April 2008 – December 2018) evaluating patients who underwent THR or Hemiarthroplasty in Greater Glasgow and Clyde. Atraumatic injuries, acetabular fractures, patients with previous procedures on the affected side and those lost to follow up were excluded. Analysis of length of admission, dislocation risk, periprosthetic fractures, infection risk, and mortality was conducted between both cohorts.

Survival time post-operatively of Group 1 patients with a THR (61.9 months) and Hemiarthroplasty (42.3 months) were comparable to Group 2 patients with a THR (59 months) and Hemiarthroplasty(42.4 months). Group 1 patients with THR had increased risk of dislocation (12.9%; p=0.04) compared to those that received Hemiarthroplasty (2.5%). Group 1 Hemiarthroplasty patients had increased wound infection risk (11.6%) compared to Group 2 (3.7%).

In conclusion, we found that amongst our population the life expectancy of a post-operative patient was short irrespective of whether they had high or low-risk alcohol consumption. A hip fracture may represent increased frailty in our study population. The Group 1 THR cohort presented a higher risk of hip dislocation and periprosthetic fracture. With this in mind, Hemiarthroplasty is a more cost-effective and shorter operation which produces similar results.


Orthopaedic Proceedings
Vol. 106-B, Issue SUPP_4 | Pages 7 - 7
8 Feb 2024
Martin DH Ng N Armstong B Brennan J Feng T Lekuse K White TO Mackenzie SP
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Myriad protocols exist for isolated Weber B lateral malleolus fractures with a congruent tibiotalar joint on initial radiographs. Stress and weight-bearing radiographs, all at various timepoints, may be employed to identify those injuries that develop significant talar shift but consensus is elusive. This study outlines a safe and reproducible protocol for such injuries, utilising a removable orthosis, immediate weight bearing and standard supine radiographs.

A retrospective analysis of a prospective trauma database was analysed to identify patients with an isolated Weber B ankle fracture with adequate presentation radiographs demonstrating a congruent mortise. Patient records and radiographs were evaluated a minimum of 5 years after initial presentation to determine ankle stability, complications, and the burden on outpatient services.

Between 2014 and 2016, 657 patients were referred to the specialist trauma clinic from the emergency department. Of the 657, 52 patients had inadequate ED radiographs to determine ankle congruity. At the two-week assessment, 11 of the 52 demonstrated talar shift and required intervention. Therefore 646 patients demonstrated ankle congruity at two weeks after weight bearing. No patient demonstrated talar shift at the six-week assessment. Average number of follow up appointments was 2.4 with 3.5 radiographs. Our new treatment protocol advocates discharge after a single orthopaedic assessment after two weeks of weight bearing.

This study supports immediate weight-bearing of Weber B ankle fractures with a congruent mortise in an orthosis. Follow up beyond two weeks is unnecessary and our protocol offers a safe means of significantly reducing the outpatient burden.


Bone & Joint Open
Vol. 4, Issue 5 | Pages 299 - 305
2 May 2023
Shevenell BE Mackenzie J Fisher L McGrory B Babikian G Rana AJ

Aims

Obesity is associated with an increased risk of hip osteoarthritis, resulting in an increased number of total hip arthroplasties (THAs) performed annually. This study examines the peri- and postoperative outcomes of morbidly obese (MO) patients (BMI ≥ 40 kg/m2) compared to healthy weight (HW) patients (BMI 18.5 to < 25 kg/m2) who underwent a THA using the anterior-based muscle-sparing (ABMS) approach.

Methods

This retrospective cohort study observes peri- and postoperative outcomes of MO and HW patients who underwent a primary, unilateral THA with the ABMS approach. Data from surgeries performed by three surgeons at a single institution was collected from January 2013 to August 2020 and analyzed using Microsoft Excel and Stata 17.0.


Orthopaedic Proceedings
Vol. 105-B, Issue SUPP_8 | Pages 146 - 146
11 Apr 2023
Sneddon F Fritsch N Skipsey D Mackenzie S Rankin I
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The Royal College of Surgeons of England (RCS) Good Surgical Practice guidance identifies essential criteria for surgical operation note documentation. The current quality improvement project aims to identify if using pre-templated operation notes for documenting fractured neck of femur surgery results in improved documentation when compared to free hand orthopaedic operation notes.

A total of fourteen categories were identified from the RCS guidance as required across all the operations identified in this study. All operations for the month of October 2021 were identified and the operation notes analysed. Pre-templated operation notes were compared to free hand operation notes.

97 cases were identified, of which 74 were free hand operation notes and 23 were pre-templated fractured neck of femur operation notes. All fourteen categories were completed in 13 (57%) of the templated operation notes vs 0 (0%) in the free hand operation notes (odds ratio 0.0052, 95% CI 0.0003 to 0.0945, p < 0.001). The median total number of completed categories was significantly higher in the templated op-note group compared to the free hand op-note group (templated median 14, range 12-14, vs. free hand median 11, range 9 to 13, p < 0.001). Logistic regression analysis of operation notes written by Registrars or Consultants identified Registrars as more likely to document the antibiotic prophylaxis given (p = 0.025).

Use of pre-templated operation notes results in significantly improved documentation. Adoption of generic pre-templated operation notes to improve surgical documentation should be considered across all operations.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_13 | Pages 25 - 25
1 Dec 2022
Asma A Ulusaloglu A Shrader MW Mackenzie W Scavina M Heinle R Howard J
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Prior to the introduction of steroid management in Duchenne Muscular Dystrophy (DMD), the prevalence of scoliosis approached 100%, concomitant with progressive decreases in pulmonary function. As such, early scoliosis correction (at 20-25°) was advocated, prior to substantial pulmonary function decline. With improved pulmonary function and delayed curve progression with steroid treatment, the role of early surgery has been questioned. The purpose of this study was to compare the post-operative outcomes of early versus late scoliosis correction in DMD. We hypothesize that performing later surgery with larger curves would not lead to worse post-operative complications.

Retrospective cohort study. Patients with DMD who underwent posterior scoliosis correction, had pre-operative pulmonary function testing, and at least 1-year post-operative follow-up, were included; divided into 2 Groups by pre-operative curve angle – 1: ≤45°, 2: >45°. Primary outcome was post-operative complications by Clavien-Dindo (CD) grading. Secondary outcomes included: age at surgery, forced vital capacity (FVC), steroid utilization, fractional shortening (FS) by echocardiogram, surgery duration, blood transfusion requirements, ICU length of stay (LOS), days intubated post-operatively, hospital LOS, infection, curve correction. Two-tailed t-test and chi-square testing were used for analysis of patient factors and CD complication grade, respectively.

31 patients met the inclusion criteria, with a mean total follow-up of 8.3±3.2 years. Steroid treatment (prednisone, deflazacort) was utilized for 21 (67.7%) patients, for a mean duration of 8.2±4.0 years. Groups were comparable for steroid use, FVC, echo FS, and age at surgery (p>0.05). Primary curve angle was 31.7±10.4° and 58.3±11.1° for Groups 1 and 2, respectively (p 0.05). Surgery duration, ICU LOS, days intubated, hospital LOS, were also not different between Groups. For the entire cohort, however, the overall complication rate was higher for patients with steroid treatment [61.9% vs 10%, respectively (p=0.008)], the majority being CDII. Neither FVC nor echo FS were different between Groups at final follow-up (p=0.6; p=0.4, respectively).

Post-operative complication rates were not different for early and late scoliosis correction in DMD. In general, however, patients undergoing steroid treatment were at higher risk of blood transfusion and deep infection. Delaying scoliosis correction in DMD while PF is favourable is reasonable, but patients with prior steroid treatment should be counseled regarding the higher risk of complications.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_6 | Pages 5 - 5
1 Jun 2022
Riddoch F Martin D McCann C Bayram J Duckworth A White T Mackenzie S
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The Trauma Triage clinic (TTC) is a Virtual Fracture clinic which permits the direct discharge of simple, isolated fractures from the Emergency Department (ED), with consultant review of the clinical notes and radiographs. This study details the outcomes of patients with such injuries over a four-year period.

All TTC records between January 2014 and December 2017 were collated from a prospective database. Fractures of the radial head, little finger metacarpal, fifth metatarsal, toe phalanges and soft tissue mallet finger injuries were included. Application of the direct discharge protocol, and any deviations were noted. All records were then re-assessed at a minimum of three years after TTC triage (mean 4.5 years) to ascertain which injuries re-attended the trauma clinic, reasons for re-attendance, source of referral and any subsequent surgical procedures.

6709 patients with fractures of the radial head (1882), little finger metacarpal (1621), fifth metatarsal (1916), toe phalanges (920) and soft tissue mallet finger injures (370) were identified. 963 (14%) patients were offered in-person review after TTC, of which 45 (0.6%) underwent a surgical intervention. 299 (4%) re-attended after TTC direct discharge at a mean time after injury of 11.9 weeks and 12 (0.2%) underwent surgical intervention. Serious interventions, defined as those in which a surgical procedure may have been avoided if the patient had not undergone direct discharge, occurred in 1 patient (0.01%).

Re-intervention after direct discharge of simple injuries of the elbow, hand and foot is low. Unnecessary deviations from protocol offer avenues to optimise consumption of service resources.


Orthopaedic Proceedings
Vol. 104-B, Issue SUPP_6 | Pages 1 - 1
1 Jun 2022
Oliver W Mackenzie S Lenart L McCann C Mackenzie S Duckworth A Clement N White T Maempel J
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The aim of this study was to identify factors independently associated with symptomatic venous thromboembolism (VTE) following acute Achilles tendon rupture (ATR), and to suggest a clinical VTE risk assessment tool for patients with ATR.

From 2010–2018, 984 consecutive adults (median age 47yrs, 73% male) sustaining an ATR were retrospectively identified. There were 95% managed non-operatively (below-knee cast 52%, n=507/984; walking boot 44%, n=432/984), with 5% (n=45/984) undergoing primary operative repair (<6wks). VTE was diagnosed using medical records and national imaging archives, reviewed at a mean of 5yrs (1–10) post-injury. Regression was performed to identify factors independently associated with VTE.

Incidence of VTE within 90 days of ATR was 3.6% (n=35/984; deep vein thrombosis 2.1% [n=21/984], pulmonary embolism 1.9% [n=19/984]). Age ≥50yrs (adjusted OR [aOR] 2.3, p=0.027), personal history of VTE/thrombophilia (aOR 6.1, p=0.009) and family history of VTE (aOR 20.9, p<0.001) were independently associated with VTE. These non-modifiable risk factors were incorporated into a VTE risk assessment tool. 23% of patients developing VTE (n=8/35) had a relevant personal or family history, but incorporating age into the tool identified 69% of patients with VTE (n=24/35). Non weight-bearing ≥2wks after ATR was also independently associated with VTE (aOR 3.2, p=0.026).

Age ≥50 years, personal history of VTE/thrombophilia and a positive family history were independently associated with VTE following ATR. Incorporating age into our suggested VTE risk assessment tool enhanced sensitivity in identifying at-risk patients. Early weight-bearing in an appropriate orthosis may be beneficial in VTE risk reduction.


Orthopaedic Proceedings
Vol. 103-B, Issue SUPP_7 | Pages 3 - 3
1 May 2021
Chen P Ng N Snowden G Mackenzie SP Nicholson JA Amin AK
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Open reduction and internal fixation (ORIF) with trans-articular screws or dorsal plating is the standard surgical technique for displaced Lisfranc injuries. This aim of this study is to compare the clinical outcomes of percutaneous reduction and internal fixation (PRIF) of low energy Lisfranc injuries with a matched, control group of patients treated with ORIF.

Over a seven-year period (2012–2019), 16 consecutive patients with a low energy Myerson B2-type injury were treated with PRIF. Patient demographics were recorded within a prospectively maintained database at the institution. This study sample was matched for age, sex and mechanism of injury to a control group of 16 patients with similar Myerson B2-type injuries treated with ORIF. Clinical outcome was compared using the American Orthopaedic Foot and Ankle Society (AOFAS) midfoot score and Manchester Oxford Foot Questionnaire (MOXFQ).

At a mean follow up of 43.0 months (95% CI 35.6 – 50.4), both the AOFAS and MOXFQ scores were significantly higher in the PRIF group compared to the control ORIF group (AOFAS 89.1vs 76.4, p=0.03; MOXFQ 10.0 vs 27.6, p=0.03). There were no immediate postoperative complications in either group. At final follow up, there was no radiological evidence of midfoot osteoarthritis in any patient in the PRIF group. Three patients in the ORIF group developed midfoot osteoarthritis, one of whom required midfoot fusion.

PRIF is a technically simple, less invasive method of operative stabilisation of low energy Lisfranc injures which also appears to be associated with better mid-term clinical outcomes compared to ORIF.


Bone & Joint Open
Vol. 2, Issue 3 | Pages 211 - 215
1 Mar 2021
Ng ZH Downie S Makaram NS Kolhe SN Mackenzie SP Clement ND Duckworth AD White TO

Aims

Virtual fracture clinics (VFCs) are advocated by recent British Orthopaedic Association Standards for Trauma and Orthopaedics (BOASTs) to efficiently manage injuries during the COVID-19 pandemic. The primary aim of this national study is to assess the impact of these standards on patient satisfaction and clinical outcome amid the pandemic. The secondary aims are to determine the impact of the pandemic on the demographic details of injuries presenting to the VFC, and to compare outcomes and satisfaction when the BOAST guidelines were first introduced with a subsequent period when local practice would be familiar with these guidelines.

Methods

This is a national cross-sectional cohort study comprising centres with VFC services across the UK. All consecutive adult patients assessed in VFC in a two-week period pre-lockdown (6 May 2019 to 19 May 2019) and in the same two-week period at the peak of the first lockdown (4 May 2020 to 17 May 2020), and a randomly selected sample during the ‘second wave’ (October 2020) will be eligible for the study. Data comprising local VFC practice, patient and injury characteristics, unplanned re-attendances, and complications will be collected by local investigators for all time periods. A telephone questionnaire will be used to determine patient satisfaction and patient-reported outcomes for patients who were discharged following VFC assessment without face-to-face consultation.


Bone & Joint Open
Vol. 1, Issue 6 | Pages 182 - 189
2 Jun 2020
Scott CEH Holland G Powell-Bowns MFR Brennan CM Gillespie M Mackenzie SP Clement ND Amin AK White TO Duckworth AD

Aims

This study aims to define the epidemiology of trauma presenting to a single centre providing all orthopaedic trauma care for a population of ∼ 900,000 over the first 40 days of the COVID-19 pandemic compared to that presenting over the same period one year earlier. The secondary aim was to compare this with population mobility data obtained from Google.

Methods

A cross-sectional study of consecutive adult (> 13 years) patients with musculoskeletal trauma referred as either in-patients or out-patients over a 40-day period beginning on 5 March 2020, the date of the first reported UK COVID-19 death, was performed. This time period encompassed social distancing measures. This group was compared to a group of patients referred over the same calendar period in 2019 and to publicly available mobility data from Google.


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_4 | Pages 2 - 2
1 Mar 2020
MacKenzie S Carter T MacDonald D White T Duckworth A
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Whilst emergency fasciotomy for acute compartment syndrome (ACS) of the leg is limb and potentially lifesaving, there remains a perception that such surgery may result in excessive morbidity, which may deter surgeons in providing expeditious care. There are limited long-term studies reporting on the morbidity associated with fasciotomy.

A total of 559 patients with a tibial diaphyseal fracture were managed at our centre over a 7-year period (2009–2016). Of these patients, 41 (7.3%) underwent fasciotomies for the treatment of ACS. A matched cohort of 185 patients who did not develop ACS were used as controls. The primary short-term outcome measure was the development of any complication. The primary long-term outcome measure was the patient reported EQ-5D.

There was no significant difference between fasciotomy and non-fasciotomy groups in the overall rate of infection (17% vs 9.2% respectively; p=0.138), deep infection (4.9% vs 3.8%; p=0.668) or non-union (4.9% vs 7.0%; p=1.000). There were 11 (26.8%) patients who required skin grafting of fasciotomy wounds. There were 206 patients (21 ACS) with long-term outcome data at a mean of 5 years (1–9). There was no significant difference between groups in terms of the EQ-5D (p=0.81), Oxford Knee Score (p=0.239) or the Manchester-Oxford Foot Questionnaire (p=0.629). Patient satisfaction on a linear analogue scale was reduced in patients who developed ACS (77 vs 88; p=0.039).

These data suggest that when managed with urgent decompressive fasciotomies, ACS does not appear to have a significant impact on the long-term patient reported outcome, although overall patient satisfaction is reduced.


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_4 | Pages 3 - 3
1 Mar 2020
Mackenzie S Hackney R Crosbie G Ruthven A Keating J
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Glenohumeral dislocation is complicated with a greater tuberosity fracture in 16% of cases. Debate regarding the safety of closed reduction in the emergency department exists, with concerns over fracture propagation during the reduction manoeuvre. The study aim was to report the results of closed reduction, identify complications and define outcome for these injuries.

188 consecutive glenohumeral dislocations with a tuberosity fracture were identified from a prospective database from 2014–2017. 182 had an attempted closed reduction under appropriate sedation using standard techniques, five were manipulated in theatre due to contra-indications to sedation. Clinical, radiographic and patient reported outcomes, in the form of the QuickDASH and Oxford Shoulder Score (OSS), were collected.

A closed reduction in the emergency department was successful in 162 (86%) patients. Two iatrogenic fractures of the proximal humerus occurred, one in the emergency department and one in theatre, representing a 1% risk. 35 (19%) of patients presented with a nerve lesion due to dislocation. Surgery was performed in 19 (10%) cases for persistent or early displacement (< 2 weeks) of the greater tuberosity fragment. Surgery resulted in QuickDASH and OSS scores comparable to those patients in whom the tuberosity healed spontaneously in an anatomical position (p=0.13). 18 patients developed adhesive capsulitis (10%).

Glenohumeral dislocation with greater tuberosity fracture can be safely treated by closed reduction within the emergency department with a low risk of humeral neck fracture. Persistent or early displacement of the tuberosity fragment will occur in 10% of cases and is an indication for surgery.


The Bone & Joint Journal
Vol. 101-B, Issue 10 | Pages 1285 - 1291
1 Oct 2019
MacKenzie SA Ng RT Snowden G Powell-Bowns MFR Duckworth AD Scott CEH

Aims

Currently, periprosthetic fractures are excluded from the American Society for Bone and Mineral Research (ASBMR) definition of atypical femoral fracture (AFFs). This study aims to report on a series of periprosthetic femoral fractures (PFFs) that otherwise meet the criteria for AFFs. Secondary aims were to identify predictors of periprosthetic atypical femoral fractures (PAFFs) and quantify the complications of treatment.

Patients and Methods

This was a retrospective case control study of consecutive patients with periprosthetic femoral fractures between 2007 and 2017. Two observers identified 16 PAFF cases (mean age 73.9 years (44 to 88), 14 female patients) and 17 typical periprosthetic fractures in patients on bisphosphonate therapy as controls (mean age 80.7 years (60 to 86, 13 female patients). Univariate and multivariate analysis was performed to identify predictors of PAFF. Management and complications were recorded.


The Bone & Joint Journal
Vol. 100-B, Issue 7 | Pages 957 - 958
1 Jul 2018
Mackenzie SP Carter TH Jefferies JG Wilby JBJ Hall P Duckworth AD Keating JF White TO


The Bone & Joint Journal
Vol. 100-B, Issue 7 | Pages 959 - 965
1 Jul 2018
Mackenzie SP Carter TH Jefferies JG Wilby JBJ Hall P Duckworth AD Keating JF White TO

Aims

The Edinburgh Trauma Triage Clinic (TTC) streamlines outpatient care through consultant-led ‘virtual’ triage of referrals and the direct discharge of minor fractures from the Emergency Department. We compared the patient outcomes for simple fractures of the radial head, little finger metacarpal, and fifth metatarsal before and after the implementation of the TTC.

Patients and Methods

A total of 628 patients who had sustained these injuries over a one-year period were identified. There were 337 patients in the pre-TTC group and 289 in the post-TTC group. The Disabilities of the Arm, Shoulder and Hand Score (QuickDASH) or Foot and Ankle Disability Index (FADI), EuroQol-5D (EQ-5D), visual analogue scale (VAS) pain score, satisfaction rates, and return to work/sport were assessed six months post-injury. The development of late complications was excluded by an electronic record evaluation at three years post-injury. A cost analysis was performed.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_19 | Pages 5 - 5
1 Nov 2017
Mackenzie S Wallace R White T Murray A Simpson A
Full Access

Kirschner wires are commonly used in paediatric fractures, however, the requirement for removal and the possibility of pin site infection provides opportunity for the development of new techniques that eliminate these drawbacks. Bioabsorbable pins that remain in situ and allow definitive closure of skin at the time of insertion could provide such advantages.

Three concurrent studies were performed to assess the viability of bioabsorbable pins across the growth plate. (1) An epidemiological study to identify Kirschner wire infection rates. (2) A mechanical assessment of a bioabsorbable pin compared to Kirschner wires in a simulated supracondylar fracture. (3) The insertion of the implants across the physis of sheep to assess effects of the bioabsorbable implant on the growth plate via macroscopic, pathohistological and micro-CT analysis.

An infection rate of 8.4% was found, with a deep infection rate of 0.4%. Mechanically the pins demonstrated comparable resistance to extension forces (p=) but slightly inferior resistance to rotation (p=). The in vivo component showed that at 6 months: there was no leg length discrepancy (p=0.6), with micro-CT evidence of normal physeal growth without tethering, and comparable physeal width (p=0.3).

These studies combine to suggest that bioabsorbable pins do not represent a threat to the growth plate and may be considered for physeal fracture fixation.


The Bone & Joint Journal
Vol. 99-B, Issue 4 | Pages 503 - 507
1 Apr 2017
White TO Mackenzie SP Carter TH Jefferies JG Prescott OR Duckworth AD Keating JF

Aims

Fracture clinics are often characterised by the referral of large numbers of unselected patients with minor injuries not requiring investigation or intervention, long waiting times and recurrent unnecessary reviews. Our experience had been of an unsustainable system and we implemented a ‘Trauma Triage Clinic’ (TTC) in order to rationalise and regulate access to our fracture service. The British Orthopaedic Association’s guidelines have required a prospective evaluation of this change of practice, and we report our experience and results.

Patients and Methods

We review the management of all 12 069 patients referred to our service in the calendar year 2014, with a minimum of one year follow-up during the calendar year 2015.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_2 | Pages 8 - 8
1 Jan 2013
Jenkins P Bulkeley M Mackenzie S Simpson H
Full Access

Introduction

The Taylor Spatial Frame (TSF) is an hexapod external ring fixation system that can move with six degrees of freedom to correct complex limb deformities. The lengths of the struts between the rings are independently adjusted to correct the deformity. The struts form an acute and obtuse “ring-strut” angle with the ring with the sum of these angles totalling 180°. In the course of a correction schedule a strut may need to be exchanged for one of longer or shorter length. The manufacturer's instructions direct that a temporary seventh strut can be placed in any orientation to ensure stability during the exchange. We have noted several episodes of temporary frame instability during this procedure resulting in discomfort. The aim of this study was to investigate which temporary strut positions gave maximal stability.

Methods

A TSF frame was constructed in a neutral alignment with a neutral strut height of 130mm. Strut 1 (red) was identified for exchange. There were 169 theoretical placement options for the temporary strut that were sequentially tested. Fast-FX™ struts were used. Strut 1 was released and the shortening that occurred was recorded using the strut length gauge. Shortening of over 10mm was considered grossly unstable.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIX | Pages 206 - 206
1 Sep 2012
Cashman J MacKenzie J Parvizi J
Full Access

Background

The diagnosis of Periprosthetic Joint Infection (PJI) is a considerable challenge in total joint arthroplasty. The mainstay for diagnosis of PJI is a combination of serological markers, including C-reactive protein (CRP), along with joint aspirate for white cell count, differential and culture. The aim of this study was to examine the use of synovial fluid CRP in the diagnosis of PJI.

Material & Methods

Synovial fluid samples were collected prospectively from patients undergoing primary and revision knee arthroplasty. Samples were assessed for CRP, cell count and differential. Three groups were analyzed; those undergoing primary knee arthroplasty, aseptic knee arthroplasties and infected arthroplasties. Demographic data, along with associated medical co-morbidities, were collected,. Statistical analysis was performed. Synovial fluid CRP was correlated with serum CRP values. Sensitivity and specificity were calculated.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVIII | Pages 40 - 40
1 Sep 2012
Oliver MC Railton P Faris P Kinniburgh D Parker R MacKenzie J Werle J Powell J
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Purpose

Elevated blood metal ions are associated with the early failure of the Hip Resurfacing Arthroplasty. The aim of this study was to analyse our prospective database of Hip Resurfacing Arthroplasty patients, to independently review the outliers with elevated blood metal ions and to determine whether a screening program would be of value at our institution.

Method

In 2004 a ten year prospective longitudinal study was set up to evaluate the clinical effectiveness and safety of Metal on Metal Hip Resurfacings in young, active adults with degenerative hip disease.

Six hundred and four patients have enrolled in this multi-surgeon prospective study with strict inclusion criteria for Hip Resurfacing Arthroplasty. All have received the same implant design. All have completed validated functional outcome questionnaires at baseline, three and six months, then annually. A sub-cohort of 196 patients underwent whole blood chromium and cobalt analysis at the same time periods.

Metal on metal bearings have a running in period of a minimum of six months before a steady state wear pattern is attained. We chose five parts per billion for Cobalt or Chromium as our threshold value. This value corresponds to the workplace exposure limit in the United Kingdom to Cobalt in whole blood. Therefore patients with ion levels greater than five parts per billion after six months were recalled for independent review, including further metal ion analysis.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_III | Pages 10 - 10
1 Feb 2012
Mackenzie D Muir R Wild S
Full Access

Background

Hip fracture in the elderly has high morbidity and mortality. National guidelines have recommended low molecular weight (LMW) heparin or aspirin for thromboprophylaxis in hip fracture. Unlike other types of major surgery, there is a lack of trial evidence for graduated elasticated compression (GEC) stockings in hip fracture patients.

Objective

To explore the effect of thromboprophylaxis on survival in hip fracture patients.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_III | Pages 2 - 2
1 Feb 2012
Walley G Bridgman S Clement D Griffiths D MacKenzie G Maffulli N
Full Access

Introduction

Fifty thousand knee replacements are performed annually in the UK at an estimated cost of £150 million. However, there is uncertainty as to the best surgical approach to the knee joint for knee arthroplasty. We undertook a randomised controlled trial to compare a standard medial parapatellar arthrotomy with sub-vastus arthrotomy for patients undergoing primary total knee arthroplasty in terms of short and long term knee function.

Methods

Two hundred and thirty-one patients undergoing primary total knee arthroplasty during 2001-2003 were recruited into the study. Patients were randomised into subvastus (116) or medial parapatellar (115) approaches to knee arthroplasty. The primary outcome measures were the American Knee Society and WOMAC Scores. The secondary outcome measures were patient-based measures of EuroQol and SF-36. All outcomes were measured pre-operatively and 1, 6, 12 and 52 weeks post-operatively. We also looked at a pain diary, analgesia diary, ease of surgical exposure, and complications.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_I | Pages 14 - 14
1 Jan 2011
Bridgman S Walley G Griffiths D dos Remedios I Clement D Mackenzie G Maffulli N
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Orthopaedic surgeons vary in their surgical approaches to total knee arthroplasty. The aim of this investigation was to compare outcomes after two different surgical approaches. The study was a prospective single-centre longitudinal randomized controlled trial. A sub-vastus approach was compared with a medial para-patellar approach. Participating surgeons elected to randomize their patients to one of the two types of approach. Outcomes included the Knee Society (KS) Clinical Rating System, WOMAC Osteoarthritis Index, SF-36, and EuroQol (measured at 1, 6, 12 and 52 weeks post-operatively compared to baseline) complications, surgeon rated ease of exposure, and proportion of patients who had a lateral release.

Two hundred and thirty one patients were randomized to the two approaches. One hundred and sixteen patients were randomized to the sub-vastus approach. At one week compared to baseline, range of motion, KS global, KS knee, and KS pain scores were significantly better in the sub-vastus group. At six weeks, the medial para-patellar group tended to have better outcomes, but not statistically significantly. At fifty-two weeks compared to baseline, the WOMAC global and pain scores, the SF36 physical function and role-physical scores, and the EuroQol utility and pain score were significantly better in the sub-vastus group. Surgeons reported the ease of exposure in the sub-vastus group was significantly worse on average.

This trial is the largest of its kind to date, and the first, so far as we are aware, to compare clinical outcomes of different surgical approaches at one year post-operatively. The sub-vastus approach to total knee arthroplasty was more effective than a medial para-patellar approach at both one week and fifty-two weeks post-operatively in patients whose surgeons considered either approach would be suitable. However, surgeons reported worse ease of exposure in the sub-vastus group.


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_II | Pages 223 - 223
1 May 2009
Mackenzie G Chess D Deshpande S Johnson J Kedgley A
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Optimal soft tissue tension maximises function following total knee arthroplasty. Excessive tension may lead to stiffness and or pain, while inadequate tension can lead to instability. Composite component thickness is a prime determinant of this soft tissue tension. The variable component thickness provided by polyethylene inserts generally allows for 2–3mm incremental change. This study analyzed the effect of 1-mm incremental changes in polyethylene thickness on soft tissue tension. Our hypothesis was that soft tissue tension would be markedly affected by increases in insert thickness.

Computer assisted TKA was performed on eight cadaveric knee specimens (four pairs). The knees were passively moved through full flexion-extension range of motion, for each tibial construct thickness. Kinematics were recorded using the computer navigation software. Soft tissue tension was analyzed by measuring compartmental loads. A validated load cell instrumented tibial insert was used to measure medial and lateral compartmental loads independently. The effect of 1-mm increments in polyethylene thickness on compartmental loads was evaluated.

An increase in compartmental loads was measured with increasing insert thickness. Loading in contralateral compartments showed differing behaviour, reflecting varying tension in the medial and lateral sides. Many generated loads showed a reduction after reaching a maximal level with further increase in insert thickness (seven of eight specimens), indicative of tissue failure, although there were no overt indications of failure during the procedure. With a 1-mm increase in insert thickness, six of eight specimens showed an increase in peak loads greater than 100N at some point in the testing procedure, although not always with the same shim thickness.

Compartmental loads varied as a function of insert thickness. Most specimens showed signs of soft tissue “micro-failure”. The high sensitivity of compartmental loads to a 1-mm incremental increase is significant and has not been previously appreciated, especially intra-operatively. Currently available inserts with 2–3mm incremental sizes may make obtaining optimal soft tissue tension difficult. In addition to the current focus of obtaining accurate leg alignment, further computer-assisted techniques are required to address soft tissue tension.


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_I | Pages 19 - 19
1 Mar 2009
Maffulli N Bridgman S Richards P Walley G Clement D MacKenzie G Al-tawarah Y Griffiths D
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Statement of Purpose: We tested the null hypothesis of no significant difference in arthroscopy rates for patients on a waiting list for arthroscopy in patients in which surgeons had a knee magnetic resonance imaging scan report prior to surgery, compared to those who did not have a report.

Methods and Results: This is a single-centre randomised controlled trial. 252 eligible patients consented and randomised. The two groups were similar with respect to a range of baseline factors. Very few arthroscopies were not performed–4.8% in the intervention arm and 5.5% in the control arm (χ2=0.06, df=1, p> 0.05). A longitudinal analysis of the secondary outcomes showed that there were no significant differences between the intervention and the control arms of the study.

Conclusion: Magnetic resonance imaging, prior to knee arthroscopy, does not lead to a reduction in the number of arthroscopies undertaken in the intervention group nor improve patient outcome in a range of secondary measures.


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_I | Pages 31 - 31
1 Mar 2009
Bridgman S Walley G Clement D Griffiths D Mackenzie G Maffulli N
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Introduction: Fifty thousand knee replacements are performed annually in the UK at an estimated cost of £150 million. However, there is uncertainty as to the best surgical approach to the knee joint for knee arthroplasty. We undertook a randomised controlled trial to compare a standard medial parapatellar arthrotomy with sub-vastus arthrotomy for patients undergoing primary total knee arthroplasty in terms of short and long term knee function.

Methods: Two-hundred and thirty-one patients undergoing primary total knee arthroplasty during 2001–2003 were recruited into the study. Patients were randomised into subvastus (116) or medial parapatellar (115) approaches to knee arthroplasty. The primary outcome measures were the American Knee Society and WOMAC Scores. The secondary outcome measures were patient based measures of EuroQol and SF-36. All outcomes were measured pre-operatively, 1, 6, 12 and 52 weeks post-operatively. We also looked at a pain diary, analgesia diary, ease of surgical exposure, and complications.

Results: Pain as measured by WOMAC was significantly less in the subvastus group but only at 52 weeks. The Knee Society Score showed some early benefit at one week to the subvastus group. There was no difference between the two groups in relation to the knee function score, EuroQol, SF-36, pain diary, analgesia usage and length of hospital stay.

Conclusion: There is some benefit to patients receiving sub-vastus arthrotomy relative to medial para-patellar. Although the results show some statistical significance in using the sub-vastus approach the clinical importance of these findings and the costs of the various procedures involved remain to be ascertained.


Orthopaedic Proceedings
Vol. 91-B, Issue SUPP_I | Pages 18 - 18
1 Mar 2009
Maffulli N Walley G Bridgman S Clement D Griffiths D Mackenzie G
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Introduction: Fifty thousand knee replacements are performed annually in the UK at an estimated cost of £150 million. However, there is uncertainty as to the best surgical approach to the knee joint for knee arthroplasty. We undertook a randomised controlled trial to compare a standard medial parapatellar arthrotomy with sub-vastus arthrotomy for patients undergoing primary total knee arthroplasty in terms of short and long term knee function.

Methods: Two-hundred and thirty-one patients undergoing primary total knee arthroplasty during 2001–2003 were recruited into the study. Patients were randomised into subvastus (116) or medial parapatellar (115) approaches to knee arthroplasty. The primary outcome measures were the American Knee Society and WOMAC Scores. The secondary outcome measures were patient based measures of EuroQol and SF-36. All outcomes were measured pre-operatively, 1, 6, 12 and 52 weeks post-operatively. We also looked at a pain diary, analgesia diary, ease of surgical exposure, and complications.

Results: Pain as measured by WOMAC was significantly less in the subvastus group but only at 52 weeks. The Knee Society Score showed some early benefit at one week to the subvastus group. There was no difference between the two groups in relation to the knee function score, EuroQol, SF-36, pain diary, analgesia usage and length of hospital stay

Conclusion: There is some benefit to patients receiving sub-vastus arthrotomy relative to medial para-patellar. Although the results show some statistical significance in using the sub-vastus approach the clinical importance of these findings and the costs of the various procedures involved remain to be ascertained.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 94 - 95
1 Mar 2008
Kedgley A Mackenzie G Ferreira L Drosdowech D King GJ Faber K Johnson J
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This in-vitro study was conducted to determine the effect of rotator cuff tears on joint kinematics. A shoulder simulator produced unconstrained active abduction of the humerus. Three sequential 1cm lesions were created, the first two in the supraspinatus tendon and the third in the subscapularis tendon. The plane of abduction moved posteriorly and became more abnormal throughout abduction as the size of the tear increased. It is concluded that in order to generate the same motions achieved by the intact joint other muscle groups must be employed, inevitably resulting in altered joint loading.

This in-vitro study was conducted to determine the effect of simulated progressive tears of the rotator cuff on active glenohumeral joint kinematics.

Five cadaveric shoulders were tested using a shoulder simulator designed to produce unconstrained active motion of the humerus. Forces were applied to simulate loading of the supraspinatus, subscapularis, infraspinatus/teres minor, anterior, middle, and posterior deltoid muscles based upon variable ratios of electromyographic data and average physiological cross-sectional area of the muscles. Three sequential 1cm lesions were created, the first two in the supraspinatus tendon and the third in the subscapularis tendon. Simulated active glenohumeral abduction was performed following the creation of each lesion. Five successive tests were performed to quantify repeatability.

The plane of abduction moved posteriorly and became more abnormal throughout abduction as the size of the lesion increased (p=0.01) (Figure 1).

In order to generate the same motions achieved with an intact rotator cuff other muscle groups must be employed, inevitably resulting in altered joint loading.

A better understanding of the effects that rotator cuff tears have on the kinematics of the glenohumeral joint may result in the development of innovative rehabilitation strategies to compensate for this change in muscle balance and improve the clinical outcomes.

Please contact author for diagram and/or graph.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 123 - 124
1 Mar 2008
Kedgley A Mackenzie G Ferreira L Drosdowech D King G Faber K Johnson J
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This study was conducted to determine the effect of passive and active muscle loading on humeral head translation during glenohumeral abduction. A shoulder simulator produced unconstrained active glenohumeral abduction using several sets of loading ratios. Significantly greater translations occurred in passive motion as compared to active motion between 30 and 70 degrees of elevation in three dimensions and in the anterosuperior plane. No difference was found between the active motions. Also, translations of the humeral head decreased with active simulation of abduction emphasizing the importance of the rotator cuff muscles in creating and maintaining the ball-and-socket kinematics of the shoulder.

This in-vitro study was conducted to determine the effect of passive and active loading on humeral head translation during glenohumeral abduction.

Five cadaveric shoulders were tested using a shoulder simulator designed to produce unconstrained abduction of the humerus. Forces were applied to simulate loading of the supraspinatus, subscapularis, infraspinatus/teres minor, anterior, middle, and posterior deltoid muscles using four different sets of loading ratios. These were based on:

equal loads to all cables (Constant-Constant);

average physiological cross-sectional areas (pCSAs) of the muscles (pCSA);

constant (Constant EMG), and

variable (Variable EMG) values of the product of electromyographic data and pCSAs.

In three dimensions, significantly greater translations occurred in passive motion as compared to active motion between 30 and 70 degrees of elevation (p< 0.001). No difference was found between the active motions. Similar results were observed in the two-dimensional resultant translations in the anterosuperior plane of the scapula, with more translation occurring during passive motion (3.6 ± 1.1mm) than active (2.1 ± 1.0mm) (p=0.002), and no significant differences between the active loading methods (Figure 1). The majority of translation tended to occur in the superior-inferior direction for all loading ratios employed.

It was clearly shown that the translations of the humeral head decreased with active simulation of abduction. These findings are in agreement with other in-vivo and in-vitro investigations.

This emphasizes the importance of the rotator cuff muscles in creating and maintaining the ball-and-socket kinematics of the shoulder.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_III | Pages 445 - 445
1 Oct 2006
Deshpande S Mackenzie G Kedgley A Johnson JA Chess DG
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Optimal soft tissue tension maximises function after total knee arthroplasty (TKA). Excessive tension may lead to stiffness and or pain, while inadequate tension can lead to instability. Composite component thickness is a prime determinant of this soft tissue tension. The thickness provided by polyethylene inserts currently allows for a 2–3 mm incremental change. This study analyses the effect of incremental change in polyethyl-ene thickness on soft tissue tension.

Computer assisted (Stryker Knee Nav) TKA was performed on 8 cadaveric knee specimens (4 pairs). Kinematic data was collected through the navigation software. The soft tissue tension was analysed by measuring compartmental loads. A validated load cell instrumented tibial insert was used to measure medial and lateral compartmental loads independently. The effect of 1mm increments in polyethylene thickness on compartmental loads was evaluated.

We measured an increase in compartmental loads with increasing insert thickness. The peak loads in each compartment showed different behaviour reflecting varying tension in the medial and lateral sides. The peak loads generated showed a reduction after reaching a maximal level with further increase in insert thickness. With a one mm increase in insert thickness, 75 % of specimens showed greater than 200 % increase in the peak loads in the lateral compartment. Similarly the medial loads showed a greater than 100% increase. Individual specimens showed a high variability in loading patterns.

Our study highlights high variation of knee loads present between subjects. The compartmental loads vary as a function of insert thickness. The high sensitivity of compartmental loads with a 1mm increment is significant and has not been previously appreciated, especially intraoperatively. The currently available TKA inserts with 2–3 mm increments may make obtaining optimal soft tissue tension difficult. In addition to the current focus of obtaining accurate leg alignment, further computer aided techniques are required to address soft tissue tension.


Orthopaedic Proceedings
Vol. 88-B, Issue SUPP_II | Pages 253 - 253
1 May 2006
Bridgman S Richards P Walley G Clement D MacKenzie G Al-tawarah Y Maffulli N Griffiths D
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Statement of Purpose: We tested the null hypothesis of no significant difference in arthroscopy rates for patients on a waiting list for arthroscopy in patients in which surgeons had a knee magnetic resonance imaging scan report prior to surgery, compared to those who did not have a report.

Methods and Results: This is a single-centre randomised controlled trial. 252 eligible patients consented and randomised. The two groups were similar with respect to a range of baseline factors. Very few arthroscopies were not performed −4.8% in the intervention arm and 5.5% in the control arm (χ2=0.06, df=1, p> 0.05). A longitudinal analysis of the secondary outcomes showed that there were no significant differences between the intervention and the control arms of the study.

Conclusion: Magnetic resonance imaging, prior to knee arthroscopy, does not lead to a reduction in the number of arthroscopies undertaken in the intervention group nor improve patient outcome in a range of secondary measures.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_III | Pages 241 - 241
1 Mar 2004
Ashcroft G Roberts S MacKenzie R Clark A Murphy E Gorman D
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Aims: To examine vibration levels produced by orthopaedic air tools and the prevalence of upper limb symptoms in orthopaedic surgeons. Methods: A preliminary measurement of vibration levels produced by six air powered orthopaedic saws was followed by a national survey of orthopaedic surgeons and controls. A health surveillance questionnaire of symptoms associated with Hand Arm Vibration Syndrome (HAVS) was sent to 1200 orthopaedic surgeons (test group) and 1200 gynaecological surgeons (controls). Results: Measured accelerations of the saws were 3.42 to 10.7 m/sec2 using BSI standards and 90.5 to 182 m/sec−2 using NIOSH standards. These vibration levels are compatible with those reported to cause significant upper limb symptoms

Survey responses were received from 741(61.7%) of the test group and 748 (62.3%) of the control group. A statistically significant increase in the prevalence of the neurological symptoms was seen among orthopaedic surgeons (p< 0.001). A significant increase in musculoskeletal problems (p< 0.008) and muscle pain (p< 0.004) was also found. No significant difference was seen in the prevalence of vascular symptoms. The neurological symptoms were not related to other potential medical causes. Conclusions: Orthopaedic surgeons report an excess of upper limb symptoms and these may be linked to vibration exposure at work.


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_I | Pages - 95
1 Mar 2002
Kurta I Richards P Dove M Rahmatall A Dove J MacKenzie G
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The aim of this study was to assess the accuracy of pedicle screw placement using NAVITRAK, a system of Computer Assisted Orthopaedic Surgery and conventional fluoroscopic technique.

Twelve porcine lumbar spines were scanned pre-operatively by computer tomography for 3-D reconstruction ( 1 mm slice thickness, 1mm increment and 2.5 mm pitch ).

Computer randomisation divided the specimens between surgeons of different experience, and the two pedicles of each vertebral level between the two surgical techniques. Stainless steel screws (6.5 spongiosa) were inserted.

Post-operatively, fluoroscopic- and CT imaging were blindly assessed for accuracy by two independent observers, and compared to macroscopic dissection of the spinal segments.

Of 168 pedicles in 12 porcine specimens, 166 received a pedicle screw. Two pedicle screw placements were abandoned. Sixyty-one screws (73%) were placed satisfactorily with the CAOS system, 56 (67.5%) in the conventional group.

In 26 pedicles the screws were placed unsatisfactorily (12 pedicles (46.2%) with the NAVITRAK system and 14 pedicles (53.8%) with the conventional technique.

The NAVITRAK system in combination with stainless steel screws showed a difference of 5.5% in misplacement in favour for the computer assisted technique.


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_I | Pages - 96
1 Mar 2002
Willcox N Kurta I Dove M Rahmatall A Dove J MacKenzie G
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The aim of this study was to demonstrate a correlation between FASTRAK readings of spinal movement and established disability scores in-patients undergoing litigation.

A retrospective, blind study was conducted on patients who had been evaluated clinically between January 1994-October 1998. Statistical regression analysis between evaluated Oswestry Disability Score (ODS) and MSPQ/Zung questionnaires and the mean ROM was obtained. 49 patients with soft tissue injuries of the cervical (n = 14) and lumbar (n = 34) spine were assessed. All of them were undergoing litigation.

A standardised Fastrak trace measuring flexion, extension, right and left bending and rotation of the cervical and lumbar spine was recorded. An ODS and MSPQ/Zung questionnaire was filled in under the supervision of a senior physiotherapist.

There was no correlation between the ODS and MSPQ/Zung and mean ROM for the cervical spine. In the lumbar spine, flexion and ODS correlated statistically significantly (p< 0.01) and right rotation with the combined MSPQ/Zung score (p< 0.014).

This preliminary study is encouraging in that it demonstrates a direct correlation between FASTRAK measurements and recognised disability scores in the lumbar spine. Further analysis of non- litigation cohorts will contribute to establish these correlations.


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_I | Pages - 96
1 Mar 2002
Kurta I Richards P Dove M Rahmatall A Dove J MacKenzie G
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The aim of this study was to assess the accuracy of pedicle screw placement comparing Computer Assisted Orthopaedic Surgery equipment with conventional fluoroscopic technique.

Twelve porcine cervical spines were scanned pre-operatively by computer tomography for 3D reconstruction (1 mm slice thickness, 1mm increment and 1 mm pitch).

Computerised randomisation divided the specimens between surgeons of different experience, and the two pedicles of each vertebral level between the two surgical techniques. Stainless steel screws (6.5 diameter, spongiosa) were inserted. Post-operatively, fluoroscopic imaging was used for accuracy assessment by two independent observers, and findings were compared to macroscopic dissection of the spinal segments.

Of 96 pedicles in 12 porcine specimens, 78 received a pedicle screw, 18 screw placements were abandoned, 38 (39.6%) were satisfactorily placed (19 in each, p> 0.05). 40 screws were misplaced, 18 (45%) with the NAVITRAK system vs. 22 (55%) with the conventional technique. These single factor results (all non-significant), were corroborated using a linear logistic regression model. Some heterogeneity in performance was detected between surgeons, independently of the type of technique used.

Computer assisted surgery is an aiming device and is not advantageous over conventional methods in spines with high bone density.


The Journal of Bone & Joint Surgery British Volume
Vol. 76-B, Issue 5 | Pages 814 - 817
1 Sep 1994
Craigen M Bennet G MacKenzie Reid R

We reviewed the records and radiographs of seven children who presented with knee pain, local tenderness over the medial femoral condyle, and radiological irregularity of the distal medial metaphysis of the femur suggestive of malignancy. In the five patients who had biopsies, histological changes were consistent with musculotendinous avulsion, and the dissection of ten cadavers confirmed the site to be the insertion of part of the adductor magnus. The recognition of this lesion and knowledge of its benign nature may avoid unnecessary anxiety and needless biopsy.


The Journal of Bone & Joint Surgery British Volume
Vol. 74-B, Issue 5 | Pages 775 - 778
1 Sep 1992
Stranks G MacKenzie N Grover M Fail T

We performed a prospective randomised controlled trial of the A-V Impulse System in 82 patients treated by hemiarthroplasty for subcapital fracture of the femoral neck. The incidence of proximal deep-vein thrombosis as assessed by Doppler ultrasonography was 23% in the control group and 0% in those using the device (p less than 0.01). Calf and thigh circumferences were measured in both groups at seven to ten days after operation. In the treatment group there was a mean relative reduction of postoperative swelling of the thigh by 3.27 cm (p less than 0.001) and of the calf by 1.55 cm (p less than 0.001). The A-V Impulse System appears to be a safe and effective method of reducing the incidence of proximal deep-vein thrombosis, and of postoperative swelling.


The Journal of Bone & Joint Surgery British Volume
Vol. 71-B, Issue 1 | Pages 30 - 32
1 Jan 1989
Roberts J Bennet G MacKenzie

We report five examples of physeal widening in four children with myelomeningocele. In all cases there was rapid clinical resolution with the use of the patients' normal orthoses and minor limitation of activity, and there was no evidence of early epiphyseal closure or growth disturbance. We suggest that recognition of the pathological process before fracture occurred may explain the rapid return to normal.


The Journal of Bone & Joint Surgery British Volume
Vol. 63-B, Issue 1 | Pages 38 - 42
1 Feb 1981
MacKenzie I Wilson J

This paper reports the results of screening 53033 infants for congenital dislocation of the hip between 1970 and 1979, and compares them with the results of a similar screening programme between 1960 to 1969. The number of dislocations missed at neonatal examination is unaltered at 0.11 per cent of live births. Operative treatment was needed in a further 0.07 per cent of the recent series even though the dislocations had been diagnosed within 24 hours of birth. The reasons for the failure of neonatal screening are discussed, and suggestions are made which will improve the situation.


The Journal of Bone & Joint Surgery British Volume
Vol. 59-B, Issue 4 | Pages 385 - 392
1 Nov 1977
Hardinge K Williams D Etienne A MacKenzie D Charnley J

Fifty-four hips converted to low friction arthroplasty between 1965 and 1975 have been reviewed one to eleven years after operation. In many cases malposition had led to degenerative changes in the opposite hip, the lumbar spine or the knee, often with severe loss of function due to pain. It was found that total replacement could give useful relief of pain and improved function, though the range of movement obtained was not as good as in primary replacement. An outstanding feature was the correction of inequality of leg length. In general, the results were much better in cases of ankylosis acquired in adult life than in cases of spontaneous fusion after sepsis in childhood. The most important complication was a single case of sciatic palsy.


The Journal of Bone & Joint Surgery British Volume
Vol. 54-B, Issue 4 | Pages 773 - 773
1 Nov 1972
Mackenzie DH


The Journal of Bone & Joint Surgery British Volume
Vol. 54-B, Issue 1 | Pages 18 - 39
1 Feb 1972
MacKenzie IG

1. A scheme was started in 1960 with the object of ensuring that the hips of all babies born in the North-Eastern Region of Scotland were examined shortly after birth.

2. 1,671 children with suspected abnormalities have been seen during the ensuing ten years, and the findings are discussed.

3. Clinical examination is essential. Radiographic examination of the newborn is not necessary and may be misleading, but it does prove that some hips with limited abduction but no instability are in fact dislocated.

4. Treatment is not started when the diagnosis is made shortly after birth. The children are re-examined at three weeks, when spontaneous recovery has occurred in about half. The others, whether they show instability or only limitation of abduction of the hips, are treated in a simple splint until they are three months old. Any residual stiffness is an indication for further splintage.

5. The first radiographs are taken when the children are three months old, and no child is discharged until the radiographs show that the upper femoral epiphyses have appeared and are in normal position.

6. We appreciate that we are treating some children who would have recovered spontaneously, but we do not know how to distinguish them. There is no evidence that splintage harms a hip.

7. Eighty-six children (5 per cent of the total) needed operation usually because the diagnosis was missed at birth.

8. Children with familial joint laxity or genu recurvatum should be examined especially carefully for associated hip abnormality.

9. The incidence of abnormality of the hips at birth is about one in fifty live births.


The Journal of Bone & Joint Surgery British Volume
Vol. 49-B, Issue 4 | Pages 652 - 657
1 Nov 1967
Adam A Macdonald A Mackenzie IG

1. Eight cases of monarticular brucellar arthritis in children are described. They have been followed up from between one and six years and all are now fully active and clinically normal.

2. The history was usually short, with limp, swelling of the joint and pain as the presenting symptoms. Constitutional disturbance was slight in all cases.

3. Diagnosis was confirmed by high concurrent serum agglutinin titres which were not found in control children of the same age from the same areas. Mercaptoethanol resistant antibody (IgG) and complement fixing antibodies were also demonstrated in the sera of four cases. One child had a positive blood culture.

4. The condition responded rapidly to rest and splintage and, to date, recovery seems to have been complete.


The Journal of Bone & Joint Surgery British Volume
Vol. 44-B, Issue 3 | Pages 648 - 651
1 Aug 1962
MacKenzie DH

Two cases of intraosseous glomus tumour of a terminal phalanx are described and the literature is reviewed.


The Journal of Bone & Joint Surgery British Volume
Vol. 44-B, Issue 2 | Pages 377 - 383
1 May 1962
Flint MH MacKenzie IG

1. Recurrence of deformity after operations for drop foot is often associated with opening of the front of the ankle joint: this has previously been regarded as a complication of the operation.

2. This study of sixty paralytic drop feet treated conservatively reveals that this laxity was in fact present in no less than 43 per cent.

3. The laxity is most commonly found when the calf muscle is strong and it can occur within a year of the onset of the paralysis. It is not always prevented by wearing a toe-raising spring.

4. Such anterior laxity may well be a common cause of failure of many of the standard operations for drop foot.

5. Before operation for drop foot is undertaken a lateral radiograph of the ankle should be taken in forced plantar-flexiori. If this demonstrates anterior laxity any standard operation is unlikely to succeed unless the anterior fibres of the collateral ligaments are protected from strain by simultaneous tendon transplantation or unless the ankle is included in the arthrodesis.


The Journal of Bone & Joint Surgery British Volume
Vol. 43-B, Issue 3 | Pages 465 - 473
1 Aug 1961
Mackenzie IG Woods CG

1 . The clinical results in forty cases of repair of the median nerve at the wrist have been examined. Almost half were unsatisfactory.

2. The factors that may have predisposed to failure of adequate re-innervation are discussed.

3. The results might be improved by the use of radio-opaque markers for early detection of separation at the suture line, and by the use of frozen sections to determine the adequacy of resection.


The Journal of Bone & Joint Surgery British Volume
Vol. 42-B, Issue 4 | Pages 689 - 705
1 Nov 1960
MacKenzie IG Seddon HJ Trevor D

1. The results of treatment of 134 patients with congenital dislocation of 167 hips are reviewed.

2. Late diagnosis is still a major problem.

3. Subluxations rarely give rise to poor results, but in dislocations first treated over the age of five years there is a one-in-three risk of failure.

4. Manipulative reduction is successful less often than reduction on a frame and carries a higher risk of avascular necrosis.

5. Closed reduction on a frame was satisfactory in 58 per cent of patients under the age of three years, and can succeed up to the age of five.

6. Open reduction was required in 20 per cent of cases under the age of three, and can be used successfully up to the age of six.

7. Seven anatomical barriers to closed reduction have been recognised and two or more are commonly found in one hip when open reduction is performed.

8. The acetabular roof may fail to develop after reduction, especially if this is delayed. A C.E. angle of under 20 degrees does not necessarily forebode this, unless measured on an arthrograph. Sclerosis of a sloping acetabular roof is an indication for operation. Acetabuloplasty is the proper operation for a sloping acetabulum and can be done successfully up to the age of twelve. Over this age, a shelf operation should be performed; this is appropriate also in younger patients in whom the curvature of the acetabulum is normal but does not extend far enough laterally. These operations were required in 38 per cent of hips treated in patients under the age of three, and in 64 per cent over this age. There is a one-in-three risk of avascular necrosis when acetabular reconstruction is done in patients under three.

9. Anteversion, if excessive, should be corrected by subtrochanteric osteotomy, and any valgus of the femoral neck should be corrected simultaneously.

10. Unilateral dislocations in patients over the age of six are best treated by Colonna's operation. In our few bilateral cases over this age our results have been disappointing.

11. Avascular necrosis is less common but more serious when it occurs over the age of three. Manipulative reduction and the use of frog-leg plasters are two avoidable factors which appear to increase its incidence. The more serious degrees are accompanied by stiffness of the hip, and when this sign is present weight bearing should be avoided.

12. Prolonged, though rarely permanent, limitation of movement occurs in some 10 per cent of cases. In a few, operative correction was required.


The Journal of Bone & Joint Surgery British Volume
Vol. 42-B, Issue 1 | Pages 60 - 64
1 Feb 1960
MacKenzie IG

1. A medial approach is preferred for arthrodesis of the wrist in reconstructive surgery because there is no interference with the extensor tendons.

2. The value of pre-operative assessment by a trial period in plaster is mentioned.

3. The technique of operation is described.

4. In the absence of active pronation, screwing the ulna to the radius in 45 degrees of pronation is advised.

5. The necessity for securing haemostasis before closing the wound is emphasised.

6. Thirty-four cases are reviewed. The shortest follow-up was one year and the longest twelve years. The result was satisfactory in all cases. Most patients were discharged from hospital after the plaster had been changed two weeks after operation. Union occurred in about sixteen weeks.


The Journal of Bone & Joint Surgery British Volume
Vol. 41-B, Issue 4 | Pages 738 - 748
1 Nov 1959
MacKenzie IG

One hundred cases of Lambrinudi's arthrodesis are reviewed. The shortest follow-up was one year. and the longest twenty-seven years. Thirty-seven per cent were successful. Nineteen per cent were failures; many of these were associated with faulty technique, and one method of operation which gives good results is described.

Success is likely if there is a balance of power between the dorsiflexors and plantarflexors of the ankle, especially if there is some fixed equinus before operation.

Success is less likely when the operation is done for a flail foot. In such circumstances arthrodesis of the ankle may have to be considered subsequently for instability of the lateral ligament, recurrence of dropfoot, or arthritis which may develop in the more active patients.

Age in itself is no bar to success, but pseudarthrosis is more likely to occur in patients over the age of twenty.