INTRODUCTION

Simulation plays an important role in surgical education and the ability to perfect surgical performance. Simulation can be enhanced by adding various layers of realism to the experience. Haptic feedback enhances the simulation experience by providing tactile responses and virtual reality imagery provides an immersive experience and allows for greater appreciation of three-dimensional structures. In this study, we present a proof-of-concept haptic simulator to replicate key steps of a cervical laminoplasty procedure. The technology uses affordable components and is easily modifiable so that it can be used from novice through to expert level. Custom models can be easily added ensuring the simulator can be used in a wide range of orthopaedic applications from baseline education through to day of surgery pre-operative simulation.

Abstract

Various studies have demonstrated that the necessity for reversal of Warfarin through the use of Vitamin K (Vit K) in neck of femur fracture patients introduces increased duration of stay and poorer outcomes as measured by operative complications and mortality rate. One reason for this delay may be the time latency between admission and the clinicians decision to investigate the INR. In this study we aim to explore the different causes of latency which contribute to a delay to theatre and ascertain whether point of care testing may negate this.

We carried out an audit of a cohort of neck of femur fracture patients between 2012 and 2015. Between September 2011 and September 2013, paper notes of 25 patients who were on warfarin at the time of sustaining a Neck of femur fracture (NOF) was obtained within Addenbrookes hospital archives. An additional 80 patients records from the year 2015 were retrieved from EPIC digital records. Time intervals were recorded as follows (from time of A&E assessment by Medical doctor); Interval to orthopaedic specialist assessment, Interval to first INR order, Interval to first INR result seen by specialist, Interval to first Vit K prescribed, Interval to first Vit K given, Interval to Second INR ordered, Interval to second INR seen by specialist, Interval to operation time (as determined by time of team briefing). Analysis of the time intervals as a proportion of total time elapsed between A&E assessment and Time to theatre was performed. Point of care (POC) testing of INR on admission to A&E was introduced and a symmetrical time period was analysed for the same intervals.

The latency generated by time taken for a NOF to be assessed by an orthopaedic specialist occupied 8.60% of the total time, the interval between ordering and recording an INR value accounted for 7.96% of time to theatre, the interval between an INR being recorded and subsequently seen by a clinician accounted for 13.4% of time to theatre, the time between orthopaedic specialist assessment and prescription of Vit K took up 7.83% of the total time and the percentage time between Vit K prescription and administration was 12.3%. The time between the first dose of Vit K prescription and arriving at theatre accounted for 76.1% of latency and the time between viewing a second INR and time to theatre occupied 33% of the total time. Following introduction of POC INR testing, there was a statistically significant decrease in time taken for warfarin reversal and consequently a reduction between time of admission to time to theatres.

NOF patients who are on warfarin at time of injury introduces complexity to surgical management and planning for theatre. In our audit we demonstrate that causes of delay are distributed throughout the pathway of care and there are several stages. POC INR testing represents an effective method of reducing this latency and improves patient outcome.

Introduction

Decreases in trainees' working hours, coupled with evidence of worse outcomes when hip arthroscopies are performed by inexperienced surgeons, mandate the development of additional means of arthroscopic training. Though virtual reality simulation training has been adopted by other surgical specialities, its slow uptake in arthroscopic training is due to a lack of evidence as to its benefits. These benefits can be demonstrated through learning curves associated with simulator training – with practice reflecting measurable increases in validated performance metrics.

To quantify the risk posed to the Lateral Femoral Cutaneous Nerve (LFCN) during Total Hip Arthroplasty using the Minimally Invasive Anterior Approach (MIAA), and during placement of the Anterior Portal (AP) in Supine Hip Arthroscopy (SHA).

Forty-five hemipelves from thirty-nine cadavers were dissected. The LFCN was identified proximal to the inguinal ligament (IL), and its path in the thigh identified. The positions of the nerve and its branches in relation to the MIAA incision and the site for AP placement were measured using Vernier Callipers.

44% of nerves crossed the incision line used in the MIAA, at an average distance of 47 ± 28mm from the proximal end of the incision. Of those that did not cross the incision line, the average minimum distance between the nerve and incision was 14.4 ± 7.4mm, occurring on average 74.0 ± 37.3mm from the proximal end of the incision. In addition, the AP was placed in the path of the nerve on 38% of occasions. The nerve took an oblique path, and when found not to intersect with the AP portal, was located 5.7 ± 4.5mm from the portal's edge. We found a reduction in risk if the portal is moved medially or laterally by 15mm from its current location.

The LFCN is at high risk of injury during both THA using the MIAA and SHA using the AP. Our study emphasises the need for meticulous dissection during these procedures, and thorough explanation of these risk whilst consenting patients. We suggest that relocation of the AP 15mm more laterally or medially will reduce the risk posed to the LFCN.

Purpose

Femoral component malrotation is a common cause for persisting symptoms and revision following total knee arthroplasty (TKA). There is ongoing debate about the most appropriate use of femoral landmarks to determine rotation. The Sulcus Line (SL, See Figure 1) is a three-dimensional curve produced from multiple points along the trochlear groove. Whiteside's Line, also known as the anteroposterior axis (APA), is derived from single anterior and posterior points. The purposes of the three studies presented are to i) assess the SL in a large clinical series, ii) demonstrate the effect of parallax error on rotational landmarks, and iii) assess the accuracy of a device which transfers a geometrically corrected SL onto the distal cut surface of the femur.

Australia is a foundation member of the Asia Pacific Orthopaedic Association—thus, recognising our geographical position in the most rapidly advancing region in the world.

It is a serious mistake to think of Asia as ‘third world’. Research, education and surgical techniques are at the forefront of modern technology. Australia has to be a part of this ‘learn and teach’ movement.

We have much to gain through exchange and travelling fellowships; paediatric, spinal, trauma and arthroplasty fellowships are available. The Orthopaedic Sports Medicine Travelling Fellowship is co-ordinated with corresponding organisations in Europe, North America and South America and previous travelling fellows become part of the influential Magellan Society.

APOA has many sections (knee, hip, hand, spine, trauma, infection, sports medicine and paediatrics), with each having regular Congresses. Join APOA and attend the Triennial Congress in Taipei November 2010 and be impressed at the level of research.

Introduction: Unicompartmental knee arthroplasty (UKA) remains a cost effective option for treatment of medial compartment osteoarthritis of the knee. In carefully selected patients survival rates exceed 90% survivorship at ten years. Main indications for revision include progressive osteoarthritis in other compartments, component loosening and polyethylene bearing failure. However, within those patients who have been revised, there is a cohort of patients who are revised early, usually under seven years. Mechanical mal-alignment has been cited recently as a reason for early failure and revision. The introduction of computer assisted surgery (CAS) has allowed us to more accurately restore the normal mechanical axis of the limb in UKA.

Aims and Hypothesis: The aim of this study was to identify whether, within our cohort of early failures, the failure mechanism differed from patients in the late revision group and specifically to examine whether mechanical mal-alignment contributed to the mechanism of early failure.

Materials and Methods: We undertook this retrospective review of a single surgeon series of 87 revised unicompartmental knee replacements carried out over 15 years. We collated the indications for revision, mechanisms of failure, and methods of revision from medical notes and compared the early and late revisions by mechanism of failure. We considered an early failure to be any UKA revised before seven years

Results: There were 50 late failure UKAs and 37 early failures. We found no significant differences between groups in age, activity or demographics at time of primary UKA. The main implants in the late failure group were 19 (38%) Miller Galante, 22 (44%) PCA Duracon, and 9 (18%) others while the early failures consisted 21 (57%) Miller Galante, 5 (14%) Oxford, 3 (8%) PCA Duracon, and 8 (22%) others. 60% of late failures were cemented while 89% of early failures were cemented. Mechanism of late failure was 46% bearing wear, 22% progression of OA, 14% malalignment and 14% loosening, while mechanism of early failure was 41% loosening, 27% bearing wear and 14% malalignment.

Discussion: Many historical bearing failures were due to oxidised polyethylene following sterilization. These should now have been eliminated by modern polyethylene and sterilization techniques. Mechanical mal-alignment is also now measurable and preventable by the use of CAS. We believe that avoidance of these two pitfalls will have an impact on the rate of early revision of UKA.

Conclusion: We conclude that patients who underwent early UKA revision had a different failure mechanism from late UKA revisions. In the early failure group the main mechanisms were mechanical loosening and bearing wear. In the late revision group, bearing failures, progressive osteoarthritis and component loosening were the main reasons for failure. Mechanical malalignment failed to differ between the groups.

Introduction Unicompartmental knee replacement (UKR) is an increasingly utilised alternative to tibial osteotomy and total knee arthroplasty in patients with single compartment degenerative disease. We report on four fractures of the medial tibial plateau following UKR.

Methods We retrospectively reviewed four cases with periprosthetic tibial plateau fractures following unicompartmental knee replacement. Each arthroplasty, performed between 1999 and 2002, was done in a community teaching hospital by a single orthopaedic surgeon and a senior level assistant. All patients had medial compartment osteoarthritis confirmed both radiographically and arthroscopically prior to arthroplasty surgery. The arthroplasties were performed by four different surgeons and three different arthroplasty systems were used. All cases were reviewed using the documented chart histories and x-ray evaluation. Each surgeon was contacted individually for the relevant case history and x-rays. The study population was composed of four females, and no males with a mean age of 63.5 years (range 58 to 68). Two patients (50%) had simultaneous bilateral UKRs performed. The remaining two patients had unilateral procedures, involving one right and one left knee. Two patients were clinically obese, and one patient had had a previous ipsilateral high tibial osteotomy.

Results The total number of fractures was four, involving three left knees and one right knee. Of the bilateral arthroplasties each patient sustained a unilateral fracture of the left knee. The patient with the previous tibial osteotomy sustained an ipsilateral fracture. Two fractures involved traumatic falls, the remaining fractures had no history of trauma. The mean post-operative period to fracture was 95.75 days with a range of 5 to 195 days. Two patients had revision surgery to total knee arthroplasty. One patient underwent internal fixation of the fracture with retention of the original prosthetic components and exchange of the polyethylene bearing. The remaining patient underwent revision of the tibial component with concurrent internal fixation and was subsequently revised to total knee arthroplasty as the result of failure. Subsequent to the described surgery all fractures have healed with no further surgical intervention.

Conclusions This series, whilst small, demonstrates that tibial periprosthetic fracture following UKR is a previously unreported but important cause of failure. Revision surgery to total knee replacement appears to be a reasonable salvage option.

Aim: To examine the flexion stability of posterior stabilised (PS) vs deep dished (DD) tibial inserts, in PCL sacrificing total knee arthroplasty using posterior stress radiography. Methods: A simple jig was designed to allow kneeling posterior stress radiographs (at 90 degrees flexion) to be taken. This method was used to take pre and post-operative radiographs in 36 knees undergoing primary arthroplasty with PCL resection (26 DD and 10 PS implants). Sagittal plane tibial translation was measured. Results: The DD inserts all showed posterior displacement (mean: −5.1 mm, range: −2 to −12mm). The PS implants were all displaced anteriorly (mean: +6.7mm, range: +3 to +12mm). The difference in translation was highly significant (P< 0.0001). There was a strong correlation between implant and position of the tibia (R=0.86). In 7 patients, comparison was possible between a DD component in one knee and a PS implant in the other. There was a mean post-operative side-to-side difference of 11mm (range: 5 to 21mm). Conclusions: This study validates a simple new method for flexion stress x-rays (by accurately discriminating between the two implant types). The posterior tibial displacement in the DD group suggests that this implant does not provide enough posterior flexion stability to compensate for the PCL resection. The anterior translation in the PS group has implications for the design and wear of the post, as well as advice to patients about possibly avoiding kneeling in this PS design.

The purpose of the study was to undertake a radiological and clinical comparison of uncemented tibial base-plate fixation with porous or hydroxyapatite coating. Knees were examined radiologically according to Knee Society Guidelines with image intensifier screening and spot films to highlight the bone prosthesis interface. Clinical assessment was performed using the Knee Society Clinical Rating.

Hydroxyapatite components were found to have significantly less radiolucent lines than porous coated. Seventy three percent of hydroxyapatite baseplates versus 28% of porous coated baseplates showed no radiolucent lines. All lucent lines in both groups appeared stable with a sclerotic margin and did not appear to be progressive or associated with component loosening. No knees showed any radiolucent lines around the stem in either group. Clinical assessment showed no significant difference between hydroxyapatite and porous coated components.

If cementless fixation is to be utilised on the tibial side in knee replacement advantage should be taken of hydroxyapatite augmentation of the component.

To determine the long term outcome and complications associated with arthroscopic synovectomy in 22 knees with rheumatoid arthritis.

A consecutive series of 22 knees in 18 patients with seropositive RA underwent arthroscopic synovectomy for painful and swollen knees unresponsive to medical treatment. All operations were performed by the senior author. The mean age at operation was 44 years (22–64). All pre-operative Xrays showed Larsen grade 2 or less and no knees demonstrated marked joint laxity. Knee Society scores were recorded pre-operatively and at review, with a mean follow-up of 8 years(6–16).

Two out of 22 knees (9%) have undergone TKR at 1 and 2 years post synovectomy. Two patients underwent further synovectomy for persistent symptoms but have since remained well. No per-operative complications were recorded but one large haemarthrosis and one stiff knee requiring manipulation were seen. The mean clinical and function scores increased by 22 and 15 points respectively at follow-up. The mean length of stay was 3 days and radiographs of the 20 knees not undergoing prosthetic replacement have all shown a small progression of degenerative radiological change.

This long-term study shows that arthroscopic synovectomy in appropriately selected patients with RA is a safe and reliable procedure with a low complication rate. The surgery is technically demanding but involves a shorter in-patient stay than with open synovectomy. The development of radiological degenerative changes were seen with all patients at review.

Aim of study: To determine the long term outcome and complications associated with arthroscopic synovectomy in 22 knees with rheumatoid arthritis.

Methods: A consecutive series of 22 knees in 18 patients with seropositive RA underwent arthroscopic synovectomy for painful and swollen knees unresponsive to medical treatment. All operations were performed by the senior author. The mean age at operation was 44 years(22–64). All pre-operative Xrays showed Larsen grade 2 or less and no knees demonstrated marked joint laxity. Knee Society scores were recorded pre-operatively and at review, with a mean follow-up of 8 years (6–16).

Results: Two out of 22 knees(9%) have undergone TKR at 1 and 2 years post synovectomy. One patient underwent a further synovectomy for persistent swelling at 2 years and has since remained well. No per-operative complications were recorded but one large haemarthrosis and one stiff knee requiring manipulation were seen. The mean clinical and function scores increased by 22 and 15 points respectively at follow-up. The mean length of stay was 3 days and Xrays of the 20 knees not undergoing prosthetic replacement have all shown a small progression of degenerative radiological change.

Conclusion: This long-term study shows that arthroscopic synovectomy in appropriately selected patients with RA is a safe and reliable procedure with a low complication rate. The surgery is technically demanding but involves a shorter in-patient stay than with open synovectomy. The development of radiological degenerative changes were seen with all patients at review.

31 consecutive patients (mean 54.7 years) were examined mean follow-up time of 47 months. Patients were evaluated clinically; using Lysholm, Cincinnati, IKDC and Tegner Activities Scores. Objective assessments were made with KT1000 Arthrometer and Isokinetic strength testing.

Lysholm scores improved from 62 preoperatively to 93 at review; Cincinnati 48 to 89; Tegner 3.6 to 5.2. 81 percent of knees were considered normal or nearly normal to IKDC, 6 abnormal, none severely abnormal. KT1000 manual max difference 2.9mm; Isokinetic flexion strength 102 percent; extension strength 95 percent. Poor results were mainly associated with advanced articular cartilage degenerative changes at time of surgery. This also correlated with increased time from injury to surgery, and increased preoperative injury rates.

This study demonstrates that the anterior cruciate ligament can be reliably reconstructed in patients over the age of 50 years with good symptomatic relief, restoration of function and return to activity.

Aim: To test the hypothesis that open surgical synovectomy of the knee results in better long-term control of chronic inflammatory synovitis of the knee than arthroscopic synovectomy.

Method: To test this hypothesis a prospective clinical trial was carried out involving three groups of patients:- In Group I (22 cases in 18 patients) arthroscopic synovectomy was performed by a surgeon experienced in arthroscopy (Bartlett). In Group II (15 cases in 11 patients) open surgical synovectomy / debridement was performed (Rush). In Group III (10 cases in seven patients) arthroscopic lavage was carried without synovectomy (Rush) and this acted as a “control” group. The patients were followed up for some 10 years. At the final review the clinical and functional scores were recorded using the H.S.S. knee score system. There are obvious problems in comparing two or three groups of patients from two separate units and these are discussed.

Results: The results showed that in both groups (i.e. Groups I & II) there was a significant shift to the right in the clinical and functional scores. This did not occur in the “control” group. In Group I, two cases out of 22 came to total knee replacement. In Group II, four cases out of 15 and in Group III, five cases out of 10 came to knee replacement.

Conclusions: It was concluded that knee synovectomy was a worthwhile procedure and that arthroscopic synovectomy was just as good and probably better than open surgical synovectomy but it needs to be done early and by a surgeon with experience in carrying out this difficult procedure.

Driving is an important part of a modern life style. ACL injury is the most common ligamentous injury of the knee. However, there is a paucity of information about the pre and post-operative ability of an ACL injured knee to respond to stimuli for specific situation such as braking reaction in an emergency. Does an ACL unstable knee affect braking reaction time? If it does, is there a difference between left and right injured knee? When is it safe to resume driving after an ACL reconstructive surgery? Is there any simple clinical test to assess patient’s recovery after surgery?

Braking reaction time of 73 patients who underwent arthroscopic ACL reconstruction and 25 normal controls was prospectively studied using a computer-link automobile simulator. Majority of these patients had autologous hamstring tendon graft. Every patients and controls were tested pre-operatively, and every 2 weeks after surgery up to 8 weeks. At each time point, two clinical tests namely stepping and standing test were also performed.

The pre-operative results did not differ significantly between controls, left ACL group and right ACL group for the braking reaction time and the two clinical tests. Post-operatively, it took 6 weeks for braking reaction time of the right ACL group to be equivalent to that of the controls, compared to 2 weeks for the left ACL group. There were a strong corelation between the stepping and standing test and the braking reaction time at each time point.

Conclusion: an ACL unstable knee does not affect patient’s braking reaction time. After a right ACL reconstruction, patient should delay at least 6 weeks before resuming driving. However, patient may resume driving as early as 2 weeks after a left ACL reconstruction. The stepping and standing test can be used at follow-up to assess patient’s recovery after surgery and to suggest appropriate time to resume driving.

The isolated arthroscopic lateral release has been already presented in the literature as an effective alternative for surgical treatment of different degrees of patellofemoral instability. This paper is to evaluate the long term results of this procedure in patients with recurrent dislocation of the patella (RDP).

Material of this study is a group of patients who underwent isolated arthroscopic lateral release for RDP with a minimum 10 years follow-up. All the patients included presented 1) clear clinical history of RDP 2) positive apprehension test 3) patella able to be dislocated under anesthesia. Were excluded from this study patients who presented 1) generalised ligamentous laxity 2) habitual dislocations of the patella 3) avulsion fracture of the patella 4) marked malalignment 5) age over 40 years. 42 patients met these criteria and 27 (28 knees) were available for follow-up. There were 13 females and 14 males with an average age of 20, 1 years and an average follow-up of 13, 4 years.

All the patients were evaluated for patellar stability and functional outcomes with both Miller and Bartlett and Crosby and Insall scores. According to the evaluation scores above mentioned 16 knees (57%) were rated as excellent /good results.

The isolated lateral release can be considered as the first approach for the treatment of RDP. The outcomes are adversely affected by long term-follow-up, however, it does not compromise any further treatment.

We evaluated the outcome of partial lateral meniscectomy of 31 knees in 29 patients whose knees were otherwise normal. The mean follow-up was 10.3 years.

According to the Lysholm score, 14 knees were rated as excellent, four as good, five as fair and eight as poor, with a mean score of 80.5 points. Radiologically, only one lateral compartment was classified as grade 0, eight as grade 1, nine as grade 2, 11 as grade 3, and two as grade 4 according to Tapper and Hoover. No significant (p < 0.05) correlation was found between the amount of tissue resected and the subjective, clinical and radiological outcome.

Although early results of lateral meniscectomy may be satisfactory, we have demonstrated that in the long term there was a high incidence of degenerative changes, a high rate of reoperation (29%) and a relatively low functional outcome score.