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Bone & Joint Open
Vol. 2, Issue 8 | Pages 599 - 610
1 Aug 2021
Hothi H Bergiers S Henckel J Iliadis AD Goodier WD Wright J Skinner J Calder P Hart AJ

Aims

The aim of this study was to present the first retrieval analysis findings of PRECICE STRYDE intermedullary nails removed from patients, providing useful information in the post-market surveillance of these recently introduced devices.

Methods

We collected ten nails removed from six patients, together with patient clinical data and plain radiograph imaging. We performed macro- and microscopic analysis of all surfaces and graded the presence of corrosion using validated semiquantitative scoring methods. We determined the elemental composition of surface debris using energy dispersive x-ray spectroscopy (EDS) and used metrology analysis to characterize the surface adjacent to the extendable junctions.


Orthopaedic Proceedings
Vol. 101-B, Issue SUPP_5 | Pages 86 - 86
1 Apr 2019
Al-Zibari M Everett SJ Afzal I Overschelde PV Skinner J Scott G Kader DF Field RE
Full Access

Background

In the late 1980's Michael Freeman conceived the idea that knee replacement would most closely replicate the natural knee joint, if the medial Tibio-Femoral articulation was configured as a “ball-in-socket”. Over the last three decades, medial rotation and medial pivot designs have proved successful in clinical use. Freeman's final iteration of the medial ball-in-socket concept was the Medial Sphere knee. We report the three-year survivorship, clinical outcomes, patient reported outcome measures (PROMs) and radiographic analysis of this implant in a multi-centre, multi-surgeon, prospective observational study.

Methods

Patients awaiting total knee replacement were recruited by four centres. They had no medical contraindication to surgery, were able to provide informed consent and were available for follow-up. Primary outcome was implant survival at six months, one, two, three and five years. Secondary outcomes were patient reported outcome measures: Oxford Knee Score (OKS), Euroqol (EQ-5D), International Knee Society Score (IKSS), IKSS Functional score and Health State score, complications and radiographic outcomes. Radiographic analysis was undertaken using the TraumaCad software and data analysis was undertaken using SPSS.


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_20 | Pages 53 - 53
1 Dec 2017
Henckel J Durand-Hill M Noory S Skinner J Hart A
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Additive manufacturing has enabled a radical change in how surgeons reconstruct massive acetabular defects in revision hip surgery. We report on the early clinical and radiological results from our methods for surgical planning, design, and implantation of 3D printed trabecular titanium implants in a cohort of patients with large unclassifiable pelvic defects.

We set up a prospective investigation involving 7 consecutive patients. Inclusion criteria was the following: 1) A history of previous total hip replacement; and 2) Current imaging showing at least a Paprosky 3B defect. Planned acetabular inclination and version was 40° and 20° respectively. Post operatively all patients had a CT scan which was analysed with software to determine component position and compared to planned. Outpatient review was done at 2 weeks (For wound), 6 weeks (for weight bearing and fixation) and 52 weeks (for fixation and infection) post-operative.

The median age at surgery was: 65 years (40–78). The median bone defect volume was 140cm3. Median surgery length was 5.2 hours (3–6.25). Median blood loss was 1300mL (450– 2000). Radiologically, components were stable and no screw breakages were identified. Achieved inclination was 41.0° (29.0–55.6) and achieved version was 15.8° (3.8–43.6). Median Oxford Hip score improved from 9 (2–44) to 25 (18–32).

We have demonstrated a new series of pre, intra and post-operative methods for reconstruction of unclassifiable acetabular bony defects. Initial clinical and radiological results are excellent considering the severity of the bony defects. We recommend the use of our or similar methods when trying to reconstruct these defects.


Bone & Joint 360
Vol. 6, Issue 1 | Pages 41 - 42
1 Feb 2017
Dale-Skinner J


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_19 | Pages 57 - 57
1 Dec 2014
Olivier A Ghani Y Konan S Khan S Briggs TWR Skinner J Pollock R Aston W
Full Access

Introduction:

Non-invasive extendible endoprostheses (NIEE) were primarily developed for salvage after musculo-skeletal tumour surgery in the immature skeleton. However, they may also have a unique application to manage complex limb reconstruction in revision surgery to address limb-length inequality in the mature skeleton. The aim of this study is to present the minimum 2 –year results of using non-invasive extendible endoprostheses for complex lower limb reconstruction.

Methods:

Between 2004 and 2013, 21 patients were treated with 23 NIEE. The indication for surgery was salvage of infected prosthesis following primary tumor resection in 6 cases, aseptic prosthesis failure after primary tumour resection in 5 cases, aseptic non-tumor prosthesis failure in 1 case, infected non-tumor prosthesis in 8 cases and symptomatic non-union of graft reconstruction in 3 cases. There were 14 male and 7 female patients with a mean age of 49.8 years (range 19–81).


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_19 | Pages 18 - 18
1 Dec 2014
Olivier A Briggs T Khan S Faimali M Johnston L Gikas P Skinner J Pollock R Aston W
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Introduction:

Pigmented Villonodular Synovitis (PVNS) is a rare inflammatory disorder of the synovium, bursa and tendon sheath. The objective of this study was to evaluate the long-term outcomes and morbidity associated with operative management of PVNS of the hand.

Methods:

Histological databases were retrospectively interrogated. All patients between 2003–2008 with confirmed PVNS of the hand were included in the study.


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_19 | Pages 29 - 29
1 Dec 2014
Olivier A Briggs T Khan S Johnston L Faimali M Gikas P Jagiello J Skinner J Aston W Pollock R
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Introduction:

Endoprosthetic replacement of the proximal femur is common in the management of bone tumours and failed revision arthroplasty. This study seeks to compare those patients undergoing acetabular resurfacing at the time of femoral replacement with those patients where the native acetabulum was preserved.

Methods:

All proximal femoral replacements from 2004 to 2009 with a five year follow up were included. Case files were interrogated to identify those that had either revision surgery or dislocation of the hip.


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_19 | Pages 58 - 58
1 Dec 2014
Olivier A Briggs T Khan S Faimali M Johnston L Gikas P Skinner J Pollock R Aston W
Full Access

Introduction:

Distal femoral replacement is recognised as the optimum treatment for malignant distal femoral tumours. Aseptic loosening is known to be a major cause for failure in these implants. Studies have indicated that the HA coated collar promotes osteointegration and bony in growth. This study compares long term aseptic loosening in implants with HA coated collars to those without in the immature skeleton.

Objectives:

To assess the effect of HA coated collars on aseptic loosening in extendable distal femoral replacement prosthesis in the immature skeleton.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_34 | Pages 473 - 473
1 Dec 2013
Panagiotidou A Bolland B Meswania J Skinner J Haddad F Hart A Blunn G
Full Access

Introduction:

High failure rates with large diameter, metal on metal hip replacements have highlighted a potential issue with the head/stem taper junction as one of the significant sources of metal ion release. Postulated reasons as to why this may be such a problem with large head metal on metal hip replacements is due to the increased torque achieved by the larger head size. This may be responsible for applying greater micromotion between the head and stem taper and consequently greater amounts of fretting corrosion. The aim of this study was to perform short term in vitro electrochemical tests to assess the effect of increasing head diameter and torque on the fretting corrosion susceptibility of the head/stem taper interface and to investigate its effect on different material combinations.

Methods:

36 mm Cobalt Chrome (CoCr) femoral heads were coupled with either a CoCr or Titanium (Ti) stem with 12/14 tapers, all with a smooth surface finish. Increasing perpendicular horizontal offsets in the sagittal plane created incremental increases in torque. Offset increments of 0 mm, 5.4 mm and 7.5 mm were selected (Figure 1) to simulate the torque force equivalent to 9 Nm, 12 Nm and 17 Nm. An inverted hip replacement setup was used (ASTM F1875-98) (Figure 2). Components were statically loaded at 0 kN and 2.3 kN prior to sinusoidal cyclic loading and electrochemical testing. Mean & fretting currents were calculated every 50 cycles up to a maximum of 1000 cycles of sinusoidal cyclic loading at 3 Hz along with the Overall Mean Current (OMC), Overall Mean Fretting Current (OMFC) and Overall Current change (OCC).


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_34 | Pages 488 - 488
1 Dec 2013
Racasan R Fleming L Bills P Skinner J Hart A Blunt L
Full Access

Background

The changes in surface roughness occurring during the wear process at the bearing surface are of great importance in trying to understand the failure mechanism of large head metal-on-metal hip replacements. The aim of the study is to identify and characterise the areal surface parameter variation between the worn and unworn areas. Surface topography variations at the bearing surface have an effect on the lubrication regime [1]. In vitro tests of these components have suggested a “self-polishing” of the surface [2]. Traditionally Ra has been used as a descriptor of surface texture. Considering the high standard of manufacturing to which these components are produced, Ra is not sufficient to describe surface morphology which requires spatial information which can only be achieved through the use of areal parameters.

Methods

A total of 50 retrieved metal-on-metal hip replacements were assessed using white light scanning interferometry (Talysurf CCI, Ametek, UK) to determine the difference in the areal surface topography parameters between the worn and unworn regions of the bearing surface. The worn area was identified by use of a previously described method [3] to produce a wear map of the bearing surface, this allows the identification of the regions of interest. A series of six measurements were taken on each component (figure 1) comprising of: 2 measurements at the equator of the head representing the unworn region, one measurement at the pole and just off centre from the pole and the rest of the measurements were taken inside and at the boundary of the wear area. Each measurement covered an area of 1 mm2 therefore it is crucial that the location of the measurement be established as accurately as possible.

Data was analysed to determine the most relevant parameters that could be used to describe and highlight the changes in surface roughness that occur during the wear process.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_19 | Pages 24 - 24
1 Apr 2013
Jalgaonkar A Mohan A Dawson-Bowling S Muthukumar T Pollock R Skinner J Cannon S Briggs T Aston W
Full Access

Introduction

Local recurrence of tumours along the biopsy tract is a known complication of percutaneous closed needle biopsy. Correct surgical management requires preoperative identification and excision of the biopsy tract at time of surgery. These tracts become increasingly difficult to identify with time, leading to risk of inadequate excision of the biopsy tract and recurrence of the tumour at the biopsy site.

Materials/Methods

In a prospective study conducted at our institution, 22 of the 45 patients with musculoskeletal tumours (49%) had unidentifiable biopsy sites, with a mean duration between biopsy and definite surgery being 98 days (range 13–164 days). We concluded that identification of the biopsy site was more difficult after 50 days. Radiotherapy related scar formation and the longer time duration between biopsy and definite surgery in patients requiring neoadjuvant therapy made identification more unlikely. Consequently, all patients received India ink skin tattoo to mark the biopsy site at the time of the needle biopsy. 56 patients were then prospectively reviewed on the day of surgery to identify the biopsy site.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_12 | Pages 2 - 2
1 Mar 2013
Hexter A Panagiotidou A Singh J Skinner J Hart A
Full Access

The articulating surface replacement (ASR) XL stemmed total hip replacement and ASR resurfacing hip systems were recalled by DePuy due to a high prevalence of early failure. The ASR XL has a greater failure rate than the ASR resurfacing, which has been increasingly attributed to wear and corrosion at the taper interface between the female taper surface of the femoral head and the male taper (trunnion) of the femoral stem. The aim of this study was to quantify the prevalence and severity of taper corrosion in retrieved ASR XL hip components.

A peer-reviewed subjective corrosion scoring system was used to quantify corrosion in a consecutive series of the 50 ASR XL hip components (head components – n=44; femoral stems – n=6) at our retrieval centre. Bearing surface wear (femoral head and acetabular cup combined) was quantified and a value of <5 microns was defined as low-wearing. Subsequent profilometry analysis was undertaken in the low-wearing hips to quantify material loss from the taper interface.

90% of components showed evidence of corrosion, with at least moderate corrosion observed in 58%. There were 17 low-wearing hips which had a median material loss from the taper interface of 3.51mm3 (range: 0.612–9.443). The median linear depth of material loss was 33μm (range: 8.5–78.0). No relationship was observed between taper corrosion and serum cobalt (r=0.204, p=0.2712) or chromium (r=0.146, p=0.432) metal ions.

Wear and material loss from metal-on-metal (MoM) hips is associated with pseudotumour formation and adverse soft-tissue reactions. We have shown that taper corrosion is extremely common in failed ASR XL hips and that wear occurs in the same degree of magnitude as at the bearing surface also occurs at the taper interface. Therefore our findings support the emerging concept of ‘taper failure’, whereby the taper is the predominate reason for failure of MoM hips. Future work must determine the relative contributions of the bearing surface and the taper interface to serum cobalt and chromium metal ion levels.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_12 | Pages 3 - 3
1 Mar 2013
Hexter A Panagiotidou A Singh J Skinner J Hart A
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Corrosion at the taper interface between the femoral head and the femoral stem is well described in metal-on-polyethylene (MoP) hips but previously was undetermined in large diameter head metal-on-metal (LHMoM) hips. The high failure rate of the articulating surface replacement (ASR) XL hip system has been partly attributed to susceptibility to corrosive damage at the taper interface. It was not known if other hip manufacturers are liable to taper corrosion. Therefore the aim of this study was to quantify the prevalence and severity of taper corrosion in LHMoM hips and compare corrosion across five different current generation manufacturers.

Taper corrosion was analysed in a consecutive series of the five most common hip types at our retrieval centre: ASR XL, DePuy (n=49); Birmingham hip resurfacing, Smith & Nephew (n=33), Durom, Zimmer (n=31), M2a Magnum, Biomet (n=14) and Cormet, Stryker (n=10). A four-scale peer-reviewed qualitative corrosion scoring system was used to quantify corrosion (none, mild, moderate and severe).

Evidence of corrosion was observed in 86% of components, with at least moderate corrosion observed in 61%. No difference in corrosion was observed between the ASR XL and the other manufacturers (p=0.202). There was still no difference seen when all manufacturers were compared individually (p=0.363). A positive correlation was observed between corrosion and femoral head diameter (r=0.224, p=0.021). However no relationship was observed with implantation time (r=0.163, p=0.118).

Our study indicates that taper corrosion is common in LHMoM hips and affects all hip types equally. The clinical significance of this finding is that all hip types will be susceptible to the complications of corrosion, such as third body wear and osteolysis. Furthermore recent reports indicate that corrosive debris released from the taper interface may play a role in the formation of pseudotumours and adverse soft-tissue reactions. We found that larger femoral head sizes showed greater corrosion, which suggests that high torque increases fretting corrosion of the taper interface. Future work must determine the optimum femoral head size and investigate the chemical composition of the corrosive debris.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_12 | Pages 4 - 4
1 Mar 2013
Hexter A Panagiotidou A Singh J Skinner J Hart A
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In metal-on-metal (MoM) total hip arthroplasty, the taper interface is where the femoral head (female taper surface) attaches to the trunnion (male taper) of the femoral stem. Corrosion is well reported in metal-on-polyethylene hips but little is known about taper corrosion in MoM devices. The aim of this study was to quantify corrosion in modern-generation stemmed MoM hip systems and gain insight into the nature of the underlying corrosive attack.

Taper corrosion was quantified in 161 failed MoM components (head components n=128; femoral stem n=33) from nine hip types with the use of a qualitative subjective scoring system. An unanticipated finding on preliminary inspection of the hips was a region on the female taper surface that contained ridges that directly corresponded with the ridged microthread on the trunnion. The ridges were not present on unimplanted (control) female taper surfaces and therefore a novel four-scale subjective scoring system was devised to quantify the prevalence and severity of this ‘imprinting’ phenomenon.

Evidence of corrosion was observed in 81% (131/161) of components, with at least moderate corrosion observed in 58% (94/161). Corrosion was greater on the female taper surface than on the male taper (p=0.034) and the two scores were associated (r=0.784, p=0.001). Imprinting affected all manufacturers and was observed in 64% (82/128) of head components. The corrosion and imprinting scores were strongly correlated (r=0.694, p=0.001). Corrosion was largely confined to the area of the female taper interface where imprinting had occurred i.e. the region that had been in contact with the trunnion microthread. Scanning electron microscopy showed evidence of fretting corrosion and substantial mechanical wear within the ridged region on the female taper surface.

Our study indicates that MoM hips are susceptible to taper corrosion. We believe it occurs by a process of “mechanically-assisted crevice corrosion,” involving the following sequence of events: joint fluid enters the taper junction as a result of pumping of fluid along the machined microthread of the trunnion. This results in galvanic corrosion of the anodic surface (the cobalt-chromium femoral head or taper sleeve). The pattern of corrosion of the head taper is determined by the surface profile of the screw thread of the trunnion, thus leaving an imprinted appearance. Historically the ridged microthread was introduced to trunnions to minimise the risk of burst fracture of ceramic heads. However this study indicates that the ridges are detrimental in MoM hips by causing extensive mechanical wear. Thus the possibility that cobalt-chrome and ceramic femoral head components require different trunnion designs needs urgent investigation.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_7 | Pages 7 - 7
1 Feb 2013
Sewell M Carrington R Pollock R Skinner J Cannon S Briggs T
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Patients with skeletal dysplasia are prone to developing advanced degenerative knee disease requiring total knee replacement (TKR) at a younger age than the general population. TKR in this unique group of patients is a technically demanding procedure due to the bone deformity, flexion contracture, generalised hypotonia and ligamentous laxity. We set out to retrospectively review the outcome of 11 TKR's performed in eight patients with skeletal dysplasia at our institution using the SMILES custom-made rotating-hinge total knee system. There were 3 males and 5 females with mean age 57 years (range, 41–79 years), mean height 138 cm (range, 122–155 cm) and mean weight 56 kg (range, 40–102 kg). Preoperative diagnoses included achondroplasia, spondyloepiphyseal dysplasia, pseudoachondroplasia, multiple epiphyseal dysplasia, morquio syndrome, diastrophic dysplasia and Larson's Syndrome. Patients were followed clinically and radiographically for a mean of 7 years (range, 3–11.5 years). Knee pain and function improved in all 11 joints. Mean Knee Society clinical and function scores improved from 24 (range, 14–36) and 20 points (range, 5–40) preoperatively to 68 (range, 28–80) and 50 points (range, 22–74) respectively at final follow-up. Four complications were recorded (36%), including a patellar fracture following a fall, a tibial periprosthetic fracture, persistent anterior knee pain and a femoral component revision for aseptic loosening. Our results suggest that custom rotating-hinge TKR in patients with skeletal dysplasia is effective at relieving pain, optimising movement and improving function. It compensates for bony deformity and ligament deficiency and reduces the need for corrective osteotomy. Patellofemoral joint complications are frequent and functional outcome is worse than primary TKR in the general population.

Submission endorsed by Mr Peter Calder, Consultant Orthopaedic Surgeon and Society member


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_1 | Pages 142 - 142
1 Jan 2013
Matthies A Suarez A Karbach L Isamailly S Henckel J Skinner J Noble P Hart A
Full Access

Introduction

Edge loading is a common wear mechanism in Metal-on-Metal (MOM) hip resurfacing and is associated with higher wear rates and the incidence of pseudotumour. The purpose of this study was to develop a method to investigate the contributions of patient, surgical and implant design variables on the risk of edge loading.

Method

We created a mathematical model to calculate the distance from the head-cup contact patch to the rim of the cup and used this to investigate the effect of component position, specific design features and patient activity on the risk of edge loading. We then used this method to calculate the contact patch to rim distance (CPRD) for 160 patients having undergone revision of their MOM hip resurfacing in order to identify any possible associations.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_1 | Pages 31 - 31
1 Jan 2013
Dhinsa B Gallagher K Dawson-Bowling S Mohan A Miles J Carrington R Skinner J Briggs T
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Introduction

The aim of this study was to see if the evaluation of the initial postoperative radiograph following primary knee and hip arthroplasty correlated with clinical outcome at five years postoperatively.

Methodology

Using our institution database we identified forty-nine hip replacements and fifty-two knee replacements performed between 2000 and 2006. All the patients underwent postoperative radiographs one day after surgery and clinical evaluation up to at least five years postoperatively. A consultant radiologist evaluated the radiographs for alignment and component position. The hip arthroplasty patients were assessed clinically using the Harris hip score, Oxford hip score, and the Western Ontario and McMaster Universities Osteoarthritis index (WOMAC). The knee arthroplasty patients were assessed using the Knee Society score, Oxford knee score, and the WOMAC score.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_1 | Pages 73 - 73
1 Jan 2013
Gillott E Sun SNM Carrington R Skinner J Briggs T Miles J
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Background

The Enhanced Recovery Programme (ERP) is an evidence based initiative aimed at speeding up patient recovery after major surgery and improving their outcomes. The Royal National Orthopaedic Hospital, Stanmore (RNOH) is a specialist orthopaedic and implemented an ERP for primary knee arthroplasties from October 2010.

Aims

To analyse the initial results of patients participating in our ERP for primary knee arthroplasty to identify what factors predict their Length of Stay (LoS) and establish where changes can be made to improve outcomes further.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_1 | Pages 140 - 140
1 Jan 2013
Matthies A Chan N Jones H Isamailly S Skinner J Noble P Hart A
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Introduction

It has been speculated that impact deformation of thin 1-piece cups used for modern metal-on-metal hip replacement may contribute to early failure. The purpose of this study was to reproduce typical impact deformation and quantify the effect of this on the frictional torque generated at the hip.

Methods

We tested nine hip couples of three designs (the ASR, BHR and Durom) and three sizes (42mm, 46mm and 50mm). A custom compression device was designed to replicate the in vivo forces and impact deformation of 1-piece metal cups reported in the literature. Each cup was mounted in the device, which itself was mounted on a mechanical testing machine. The cups were compressed with incremental loads up to a maximum of 2000N. At each increment we measured cup deformation, and then the head component was seated into the cup. The hip was lubricated and the head component rotated 60 degrees axially within the cup and the axial torque was measured.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIX | Pages 115 - 115
1 Sep 2012
Gillott E Kahane S Aston W Briggs T Skinner J Pollock R
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Aims

Present the outcomes of those patients diagnosed with Ewing's Sarcoma of the foot within the past 10 years and treated at the Royal National Orthopaedic Hospital's Bone Tumour Unit, Stanmore.

Methods

Retrospective study of the cases identified from the pathology database. Notes reviewed for presentation, treatment and follow up. TESS (Toronto Extremity Salvage Score) and MSTS (Musculoskeletal tumour score) were calculated.