header advert
Results 1 - 9 of 9
Results per page:
Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_3 | Pages 10 - 10
1 Apr 2015
Mackay N Mahmood F Chan K Baird K McMillan S Logan J Dowell C Miller R
Full Access

Ankle lateral ligament complex injury is common. Traditional ‘Brostrum’ repair, performed either open or arthroscopically, still has a protracted post-operative period. The ‘Internal Brace’ provides a scaffold for the ligament repair and acts as a ‘check-rein’ preventing further injury.

16 patients with ankle instability and injury to the Anterior-Talo-Fibular-Ligament (ATFL) confirmed on MRI were identified. All had completed a period of conservative treatment. All had symptoms of pain in the region of the ATFL and described a feeling of instability. Surgery was performed under general anaesthetic and regional popliteal block. Anterior ankle arthroscopy demonstrated a positive ‘drive through’ in all cases. The ATFL was absent and in the majority replaced by incompetent scar. Scar tissue was removed from the anterior aspect of the ankle allowing visualisation of the fibula and lateral talar neck. Using the Internal Brace system (Arthrex), a 3.5mm swivel-lock with fibre-tape was placed into the fibula. With the ankle in plantar flexion, to allow appropriate tensioning, the distal end of the fibre-tape was secured to the talar neck, at a 45 degree angle, with a 4.75mm biotenodesis screw. The patient was placed into a moon-boot for 7–10 days and mobilised fully weight-bearing. Pre-op score, using EDQ-5, MOXFQ, AOFAS and visual analogue scores, with post-op PROMS were performed.

All patients reported improvement in their symptoms at 6 week visit. The majority were back to normal activities at 12 weeks. The few that were not, had missed physiotherapy appointments for various reasons. There were no infections and no implant failures.

Arthroscopy allows direct visualisation for accurate placement of the Internal Brace. Post-operatively recovery is expedited due to the stability provided by the ‘Brace’, permitting a more aggressive rehabilitation programme. The greatest potential is arguably for the elite athlete, where an accelerated return to full activity has significant occupational implications.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXVII | Pages 27 - 27
1 Jun 2012
Miller N Carry P Chan K Strain J Swindle K Rousie D
Full Access

Introduction

Studies of the vestibular system in patients with idiopathic scoliosis (IS) have shown abnormalities in the semicircular canals (SCC) and the basicranium. Rousie (2008) revealed a statistically increased incidence of structural anomalies in the SCCs with three-dimensional computer generated modelling. Some of these findings were replicated in a small population by Cheng (2010). The primary goals of this investigation are verification of SCC abnormalities of patients with IS versus controls with use of three-dimensional modelling with subsequent development of a unique phenotypical classification. Our long-term goal is to provide new direction for hypothesis directed identification and characterisation of genes causally related to IS.

Methods

20 patients with IS and 20 controls matched for age and sex will be identified through the clinic with approval from the institutional review board. Power analyses were done to detect the difference in distributions as the proportion of fisher tests with p values less than 0·05. A sample size of 20 per group gives 86–99% power to realise results under conservative assumptions. IS patients and controls undergo vestibular system examination via T2 MRI imaging. Extracted data are evaluated by a team including Dr Rousie, ENT, radiology, and orthopaedic surgery. DNA is extracted with Gentra Puregene kits from Qiagen (Valencia, CA, USA). Developmental genes related to SCC and axial somatogenesis are being identified through a bioinformatics approach, targeting known IS genomic loci. Custom single-nucleotide polymorphism panels, statistical linkage, and association will identify genes of significance for sequencing.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XVIII | Pages 62 - 62
1 May 2012
Chan K Wong J Thompson N
Full Access

INTRODUCTION

Intramedullary nail fixation has been used for successful treatment of long bone fracture such as humerus, tibia and femur. We look at the experience of our trauma unit in treating long bone fracture using the AO approved Expert femoral/tibial nail and proximal femoral nail antirotation (PFNA). We look at the union and complication rates in patients treated with AO approved nailing system for pertrochanteric, femoral and tibial shaft fracture.

METHODS

We carried out retrospective case notes review of patients that underwent femoral and tibial nailing during the period of study- October 2007 to August 2009. All patients were treated using the AO approved nailing system. We identified all trauma patients that underwent femoral and tibial nailing through the trauma register. Further information was then obtained by going through medical notes and reviewing all followed-up X-rays stored within the online radiology system.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XVIII | Pages 89 - 89
1 May 2012
Chan K Koh H Zubairy A
Full Access

INTRODUCTION

Warfarin remains the treatment of choice for the majority of patients with venous thromboembolism, atrial fibrillation and valvular heart disease or valve replacement unless contraindicated. Poor management of patients on warfarin often leads to delay in surgery, life threatening bleeding during or after operation and unnecessary delay in discharge from hospitals in United Kingdom.

METHODS

We carried out a prospective study on patients who were on warfarin and underwent elective and emergency orthopaedic procedures during period of study- August 2007 to April 2008. All patients included in the study were identified from admission notes during period of study. All data regarding indications for warfarin, pre and post procedures INR, elective or emergency orthopaedic procedures and complications were collected using a standard proforma.


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_II | Pages 117 - 117
1 Feb 2012
Wong F Yung P Chan K
Full Access

Injuries to the infra-patella branch of the saphenous nerve on harvesting Bone-Patella Tendon-Bone (BPB) autograft commonly cause anterior knee pain. The purpose of this study is to investigate the possibility of harvesting a good BPB graft without injury to the nerve by using double mini-incision.

Twelve adult cadaveric knees, with two vertical incisions of 25mm, one over the inferior pole of the patella, and the other over the tibial tuberosity were prepared. The tibial bone block was harvested, with preservation of the para-tendon, making a subcutaneous tunnel proximally and stripped to dissect the middle 1/3 of the patella tendon. The graft was then detached after harvesting the patella bone block, and examined for size and quality. The knees were finally dissected to check the relationship of the incisions with the infra-patella branch, and see if it was injured.

All BPB grafts were found to have good tendon qualities of average 9.5mm in width. The tibial bone plug is of average 25mm in length and 10mm in width, while the patella bone plug is of average 22mm in length & 9mm in width. All 12 knees have 2 infra-patella branches, with the proximal branch running at averaged distance of 23mm distal to the proximal incision, while the distal branch lying at averaged distance of 11mm proximal to the distal incision. 2 out of the 12 distal branches were injured by the distal incision.

Double-mini incision allows harvesting of a consistently good quality BPB graft with preservation of the infra-patella branch of the saphenous nerve.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 427 - 427
1 Nov 2011
Takemoto R Arno S Kinariwala N Chan K Hennessy D Nguyen N Walker P Fetto J
Full Access

Over the last two decades, design modifications in cementless total hip arthoplasty have led to longer lasting implants and an increased success rate. However, there remains limitations to the cementless femoral stem implant. Traditional cementless femoral components require large amounts of bone to be broached prior to stem insertion (1). This leads to a decrease in host bone stock, which can become problematic in a young patient who may eventually require a revision operation during his or her lifetime. Osteopenia, only second to distal stress shielding can lead to aseptic loosening of the implant and stem subsidence, which also accelerates the need for a revision operation (24). Recent literature suggests that thigh pain due to distal canal fixation, micro-motion, uneven stress patterns or cortex impingement by the femoral stem is directly correlated to increased stem sizes and often very disabling to a patient (58). In this study, we sought to determine whether reducing stem length in the femoral implant would produce more physiologic loading characteristics in the proximal femur and thus eliminate any remaining stress shielding that is present in the current design. We analyzed the surface strains in 13 femurs implanted with

no implants,

stemless,

ultra short and

short stem proximal fill implants in a test rig designed to assimilate muscle forces across the hip joints, including the ilio-tibial band and the hip abductors.

Analysis of the resulting surface strains was performed using the photoelastic method. For each femur, intact and with the different stem length components in place, the fringe patterns were compared at the same applied loads. The highest fringe orders observed for all tests were located on the lateral proximal femur and medial proximal femur. The fringes decreased as they approached the neutral axis of bending (posterior and anterior). Distal fringe patterns were more prominent as the stem length increased. The results demonstrate that the stemless design most closely replicated normal strain patterns seen in a native femur during simulated gait. The presence of a stemless, ultra short and short stem reduced proximal strain and increased distal strain linearly, thereby increasing the potential for stress shielding. The stemless design most closely replicated normal strain patterns observed in a native femur and for this reason has the potential to address the shortcomings of the traditional cementless femoral implant.


Orthopaedic Proceedings
Vol. 90-B, Issue SUPP_I | Pages 26 - 26
1 Mar 2008
Tong C Griffith J Antonio G Chan K
Full Access

[Hong Kong Orthopaedic Association, Travelling Fellow]

Glenoid bone loss predisposes to further dislocation and failure of arthroscopic Bankart repair in patients with recurrent shoulder dislocation. This study investigates quantification of glenoid bone loss in anterior shoulder dislocation using computerized tomography (CT).

CT was performed in 40 patients (average age 31 years, range 16–82 years) with anterior shoulder dislocation. Of this group, 42 shoulders with anterior dislocation and 38 contralateral normal shoulders were examined. In addition, twenty shoulders in ten normal subjects were examined. CT technique comprised 1mm acquisition, pitch 1.0, simultaneously of both shoulders. Reformatted images en face to the glenoid fossa were obtained. Ten different measures of the glenoid fossa were obtained including cross sectional area, maximum height, and width and flattening of the anterior curvature of the glenoid.

In normal subjects, maximum side to side difference in cross-sectional area was 14% and maximum glenoid width 4.1mm. For dislocating shoulders, flattening of the anterior edge of the glenoid fossa and a reduction in maximum glenoid width were the best objective criteria of bone loss. Flattening of the anterior glenoid curvature was a feature of 95% dislocated shoulders though was only seen in 1.5% of normal shoulders. Glenoid cross-sectional area was not a useful measure of glenoid bone deficiency.

Variable glenoid bone loss is a measurable feature of anterior shoulder dislocation. CT can be used to objectively assess this preoperatively. This should help when deciding on whether to perform an arthroscopic Bankart repair or open bone block procedure.


The Journal of Bone & Joint Surgery British Volume
Vol. 74-B, Issue 6 | Pages 848 - 852
1 Nov 1992
Kendall N Hsu S Chan K

We reviewed 19 adults and 12 children who had been treated for avulsion fractures of the tibial spine. Adult injuries have not previously been reported at length; most were caused by road-traffic accidents, and 68% were associated with other injuries, of which 58% were around the knee. The higher incidence of associated injuries in adults as compared with children, indicates that the injury is the result of greater energy and perhaps a different mechanism. The worse outcome in some adults was due to other associated intra-articular fractures and tears of the medial collateral ligament. Arthroscopy is useful in both diagnosis and treatment. Early accurate diagnosis and the correct treatment produce a good outcome.


The Journal of Bone & Joint Surgery British Volume
Vol. 65-B, Issue 3 | Pages 291 - 298
1 May 1983
Lamb D Chan K

A review is presented of 41 patients with traumatic tetraplegia on whom reconstructive surgery of the upper limb was carried out. Twelve patients were followed up for more than 10 years after operation and the average period overall was seven and a half years. Tendon transfers were made with the aim of providing extension of the elbow or restoring a useful grasp or a combination of both. The assessment was carried out on four main aspects: the function of the elbow, the function of the hand, the ability to carry out the activities of daily living and the effect of the surgical reconstruction on the personal and social achievement of the patient.