Background and Aims

Many orthopaedic patients admitted to hospital who require urgent surgery are also on Warfarin. Patients with an INR>2 have an increased risk of bleeding complications during surgery; however delay to surgery due to a high INR has both clinical and financial implications. This audit evaluates whether the appropriate management for correction of INR is employed as per local guidelines and, if not, whether this results in significant delay to operative treatment.

Introduction

We aimed to retrospectively identify risk factors for delayed / non-union for first metatarsophalangeal joint fusion.

The rate of surgical site infection after elective foot and ankle surgery is higher than that after other elective orthopaedic procedures.

Since December 2005, we have prospectively collected data on the rate of post-operative infection for 1737 patients who have undergone elective foot and ankle surgery. In March 2008, additional infection control policies, focused on surgical and environmental risk factors, were introduced in our department.

We saw a 50% reduction in the rate of surgical site infection after the introduction of these measures. We are, however, aware that the observed decrease may not be entirely attributable to these measures alone given the number of factors that predispose to post-operative wound infection.

Cite this article: Bone Joint J 2015;97-B:516–19.

Our Trust's prophylactic antibiotic regime for elective hip and knee replacements recently changed, following the publication of Department of Health guidelines aimed at reducing the incidence of Clostridium Difficile associated diarrhoea (CDAD). We aimed to assess whether this change has reduced the incidence of post-operative CDAD.

We reviewed all primary and revision total hip and knee replacements performed in Gloucestershire Royal Hospital between April 2007 and March 2010. Up to August 2008, patients received prophylaxis with cefuroxime (Group A). This subsequently changed to flucloxacillin and gentamicin (Group B). All patients who developed CDAD within one month of surgery were identified and their case-notes were reviewed for the presence of CDAD risk factors, such as concomitant use of broad-spectrum antibiotics.

3117 patients were included and 15 developed CDAD (0.48%); 12 patients (0.77%) from Group A and 3 from Group B (0.19%), representing a four-fold decrease. Analysis of a 2×2 contingency table with Fisher's exact test showed that the difference between the two groups was statistically significant (P=0.0347).

Case-note analysis revealed that 8/12 patients in Group A and 1/3 patients in Group B had other risk factors for developing CDAD. Excluding these patients, the difference between the two groups was not statistically significant (P=0.218).

CDAD is exceedingly rare following total joint replacement surgery, especially when the only antibiotics given are prophylactic. Our figures are in line with a general decline in CDAD nationally from 2007. This decline is most likely due to multiple factors, such as hand-washing, barrier nursing and restrictive antibiotic policies. The effect of the change in prophylaxis is therefore difficult to quantify. Choice of prophylactic antibiotics should be based upon their efficacy alone, not their potential to reduce CDAD.

1737 elective foot and ankle cases were prospectively audited from Dec 2005 to end June 2010. All cases were brought back to a specialist nurse dressing clinic between 10 and 17 days post op. Data was collected at the dressing clinic with a standardised proforma on the type of surgery, the state of the wound and any additional management required. Those patients with a pre-existing infection were excluded.

Of the 1737 cases 201 (11.6%) had a minor wound problems such as excessive post op bleeding into the dressings, suture problems, early removal of K wires, delayed wound healing and minor infection. 42 patients required antibiotics (2.4%) 8 patients had a deep wound infection (0.5%) requiring intravenous antibiotics and or further surgery.

There were 1185 forefoot procedures 36 of which developed an infection (3%), overall infections of the mid/hindfoot was 6 (1%).

Practice has changed as a result of the audit (reviewed annually). We have changed our closure techniques (reducing suture problems). For the past 2 years all of our elective foot and ankle patients now go to an ultra clean ward (Joint Replacement Unit) and we have shown a reduction in infection rates by over 50% since. Our infection rate before the JRU was 3.3% with 0.7% deep infection rate (818 procedures) and after the introduction of the JRU our infection rate has ped to 1.6% superficial and 0.3% deep infection p<.001.

This large series prospective study sets a benchmark for infection rates in elective foot and ankle surgery. It also highlights the benefit of a dedicated orthopaedic elective unit with rigorous infection control policy and the need to regularly review our results.

It has been shown that a cognitive function (CF) loss can occur after hip or knee arthroplasty procedures, with an incidence of 40 to 70%. The pathogenesis remains unclear but studies suggest some form of brain emboli; although both trans-cranial doppler and trans-oesophageal doppler have both shown emboli per-operatively a correlation has never been shown with CF loss post-operatively. In contrast, in the cardiothoracic literature an embolic cause is widely accepted for detectable post-operative CF drop. The purpose of this study was to ascertain whether MRI could show evidence of embolic phenomena in patients undergoing hip or knee arthroplasty.

Twenty-five patients presenting for hip or knee arthroplasty procedures were consented for this study. Brain MRI scans and MR angiograms were performed 1 week pre-operatively and within 1 week post-operatively using a Phillips 1.5Tesla MRI unit. All scans recorded were independently reviewed by 2 radiologists. A series of tests to examine several modes of cognitive function were carried out by a clinical psychologist pre-operatively, and at 1 week post-operatively. The CF tests showed a clinically significant drop following surgery in 64% of cases – this is in keeping with other recently published data.

None of the post-operative scans or angiograms showed overt evidence of new lesions. Three Scans had equivocal tiny brainstem hypodensities on a single slice with no correlating abnormality on diffusion images to support the presence of new ischaemia.

We conclude that either the aetiology of post-operative CF drop following arthroplasty is not embolic in nature, or that with current technology MRI brain scans even with angiograms are not sensitive enough to show the corresponding abnormality. With currently available equipment there appears to be no benefit from using MRI as a tool to evaluate post-operative CF loss in this group of patients.

Scarf osteotomy is a commonly performed method of hallux valgus correction. Release of deforming lateral soft tissue structures is an integral part of this correction. The aim of this study was to determine if there was any difference in the correction achieved by dorsal and transarticular releases as part of a scarf osteotomy.

This radiological study was performed at a single institution. One surgeon utilised the dorsal first web approach for the distal soft tissue release and one the transarticular approach. There were 23 patients in each group. The same post-operative regime was used on both sets of patients. Data was collected on hallux valgus angle (HVA), intermetatarsal angle (IMA) and AFS sesamoid scoring.

The pre-operative deformity as measured by hallux valgus angle and intermetatarsal angle where similar for both groups (p= 0.25, 0.79 respectively) with a significant difference in severity of AFS scoring in the dorsal group (p < 0.001). Patients who underwent a dorsal approach release had a mean improvement in IMA of 5.46 degrees compared to 3.86 in the transarticular group. The HVA improved by 17.92 degrees in the dorsal group compared to 8.08 in the transarticular group. Both these results were statistically significant (p= < 0.01,< 0.002 respectively). There was a statistically significant difference in number of patients returning to within normal limits of the HVA (p= < 0.05); 18 patients returned to a normal hallux valgus angle after undergoing the dorsal approach compared to 9 patients in the transarticular group.

Our study shows that when performing a distal soft tissue release in conjunction with a scarf osteotomy for correction of hallux valgus, a dorsal first web approach is significantly better at correcting the HVA as compared to a transarticular approach. We would, therefore, recommend the use of a dorsal approach when performing this surgery.

Cognitive dysfunction has been well documented following total knee replacement. Possible causes that have been postulated include cerebral emboli, post-operative complications and pain. The aim of this study is to compare cognitive decline in patients undergoing conventional total knee replacement (TKR), navigated total knee replacement and total hip replacement (THR).

We prospectively analysed 75 patients undergoing lower limb arthroplasty. Group 1 consisted of 25 conventional TKR’s, group 2 consisted of 25 navigated TKR’s and group 3 consisted of 25 THR’s. Cognitive function was assessed by 11 validated neuropsychological tests preoperatively, at 1 week post-operatively and at 6 months post-operatively. Testing was carried out by a clinical psychologist.

At day 6 post-operatively 55% of group 1, 83% of group 2 and 61% of group 3 patients had a significant cognitive decline. Group 2 had a significantly greater cognitive decline at day 6 compared to the other 2 groups. At 6 months significant cognitive decline was found in all 3 groups to 21%, 16% and 34% respectively. Group 2 demonstrated the greatest improvement in cognition from day 6 to 6 months post-operatively

Significant cognitive decline occurs in two-thirds (66%) of all patients undergoing lower limb arthroplasty at day 6 and remains significant in a quarter (25%) of patients at 6 months. There was no significant difference in cognitive decline in patients undergoing hip and knee arthroplasty.

Introduction: Pedobarograph systems are used to measure foot pressure characteristics during gait. These measurements help clinicians diagnose pathology and assess treatment outcome. While most patients can walk across the Pedobarograph footplate unaided, some patients ask if they can use their crutch.

Aim: The aim of this study was to assess the effect of using a crutch on pedobarograh measurements.

Materials and Methods: A Musgrave Pedobarograph system was used to measure the foot pressure characteristics of twenty feet in ten normal subjects. The group’s mean age and weight were 31 years (SD=6) and 78 kg (SD=12), respectively. Each subject had each of their feet measured 3 times as they walked across the foot plate unaided. These measurements were then repeated with the subject using a crutch on the contralateral side to that being measured. The force through the crutch was recorded using a set of scales to ensured consistency between measurements.

Results: The main foot pressure characteristics are listed below. The table shows the mean value of the normal parameter, along with the percentage difference of the mean values when the crutch was used. The results of a paired-t test are also given to indicate the statistical significance of the change.

In addition to the above quantitative changes, qualitative assessment of the data showed an alteration in the loading pattern with reduced push off forces. However, eighteen of the twenty feet showed no alteration in the pattern of pressure distribution.

Conclusion: These results show that a crutch affects normal gait by generally increasing the time parameters and reducing the load and pressure parameters. The only parameters not significantly affected by the crutch were “Push off duration” and “Time to peak heel strike pressure”.

Aim We set out to see

whether ankle replacements were capable of maintaining a normal gait and

Method We performed gait analysis on 15 patients, with 13 ankle replacements (mixture of Buechel Pappas and Scandinavian Total Ankle Replacement [STAR]) and three ankle arthrodeses. One patient had an ankle replacement on one side and an arthrodesis on the other. We used a standard seven camera infrared system and force plate at a frequency of 240Hz.

There were a mixture of patients with osteoarthritis and rheumatoid arthritis. We also looked at the ‘normal’ side of the patients with unilateral surgery.

Results We found that patients with ankle replacements had near normal gait parameters for both kinetic and kinematic data whereas patients with ankle fusions had significantly altered kinetic and kinematic data. This was both in respect to normal individuals and to the unoperated side. Patients with rheumatoid arthritis had some alteration in the gait pattern on the normal side – the presence of an ankle replacement on the other side maintained this pattern on the operated side, suggesting that this was not due to abnormalities within the ankle but in the rest of the foot and lower limb. Patients with unilateral osteoarthritis for which they had an ankle replacement had essentially normal kinetics and kinematics of both ankles.

Conclusion We have been able to show that an ankle replacement performs well in terms of restoring/maintaining a normal gait pattern, whereas ankle arthrodesis, although gives a functional and pain free foot, significantly alters the normal gait pattern.

Introduction and Aims: The study was designed to compare the early results, prospectively, of the fixed-bearing Zimmer NexGen cruciate retaining (CR) and the Zimmer NexGen mobile-bearing knee (MBK) knee arthroplasty. The study was designed to determine whether differences exist in the clinical outcomes between patients receiving different types of bearings.

Method: Patients were randomly assigned to receiving either fixed or mobile bearings. Patients were blinded but not assessors to the type of arthroplasty. The study commenced in June 2000. By November 2002, 69 and 70 patients had been recruited into the CR and MBK groups respectively. Consultants were present in 92% of operations and the rest were performed by a senior registrar. The major indication was osteoarthritis (64 CR: 65 MBK). The surgical approach was medial parapatellar in 65 CR and 63 MBK the rest were subvastus, patella resurfacing was not routinely employed. Pre-operative, intra-operative and post-operative data was collated.

Results: The body mass index was 32 ± 7 CR and 32 ± 6 MBK. The average age was 67 ± 8 CR and 67 ± 8 MBK. Pain in the contralateral knee was present in 79.7% CR and 74.3% MBK group. Minimum post-operative follow-up was one year. There was no significant difference in the pre-operative and post-operative fixed flexion contracture, 4.3 ± 5.4 to 1.0 ± 2.9 CR and 6.2 ± 6.9 to 0.9 ± 2.8. The mean flexion pre-operatively and post-operatively between the two groups was not significantly different 108 ± 19 to 105 ± 16 CR and 107 ± 15 to 102 ± 13. Patello-femoral joint symptoms diminished from 67% to 12% CR and from 69% to 21% in the MBK group. The dependence on walking aids diminished from 50.7% to 16.7% CR and 51.4% to 26.9% MBK. At one year, nine percent and 21% were dissatisfied in the CR and MBK groups respectively. In the CR group, two revisions had been performed, one for infection and the other for arthrolysis and poly exchange. Two revisions had been carried out in the MBK group, one for extreme ‘clunking’ and the other for arthrolysis with poly exchange.

Conclusions: The one-year results suggest that the levels of dissatisfaction and patello-femoral problems are significantly greater in the mobile bearing group as opposed the fixed bearing. The early results would not encourage the use of the mobile bearings. We await the long-term results as regards survivorship of the bearings.

There is increasing evidence that non-steroidal anti-inflammatory drugs (NSAIDs) can adversely affect bone repair. We have, therefore, studied the in vitro effects of NSAIDs, which differentially inhibit cyclooxygenases (COX), the prostaglandin/thromboxane synthesising enzymes, on human osteoblasts. Indomethacin and the new nitric oxide (NO)-donating NSAIDs block the activity of both COX-1 and COX-2. Indomethacin and 5,5-dimethyl-3-(3 fluorophenyl)-4-(4 methylsulphonal) phenyl-2 (5H)-furanone (DFU) reduced osteoblast numbers in a dose-dependant manner and increased collagen synthesis and alkaline phosphatase activity. The reduction in osteoblast numbers was not caused by loss of adhesion and was reversible. Neither NSAID influenced DNA synthesis. There was no difference between the effects of indomethacin and DFU. NO-NSAIDs did not affect cell numbers.

These results suggest that care should be taken when administering NSAIDs to patients with existing skeletal problems and that NO-NSAIDs may be safer.

Introduction Proximal femoral fractures (PFF) in the elderly have high complication rates contributing to associated morbidity and mortality. This study aimed to identify any specific patterns or factors contributing to surgical failures requiring re-operation in these patients.

Methods A retrospective review of 441 PFF treated operatively during a consecutive 27 month period was performed. Relevant data was obtained from operation records, medical records and x-ray reviews. The re-operation rate was calculated according to the fixation method (e.g. DHS) as well as fracture type (e.g. intertrochanteric).

Results Of the PFF treated operatively 40 required subsequent procedure(s). There were 28 mechanical failures and 12 deep infections. Of the mechanical failures four required more than one subsequent operation and five patients died within six months of revision surgery. Technical error was a significant factor in six of the 28. Repeat falls during the post-operative rehabilitation phase accounted for the majority of periprosthetic fractures. Of the deep infections five required removal of hardware and seven underwent incision and drainage. Dynamic condylar screw fixation for the subtrochanteric fractures had higher mechanical failure (50%) compared to intramedullary nail fixation (13%).

Conclusions Technical error, improper implant selection and falls during post-operative rehabilitation period are significant factors contributing to failures in PFF fixation and should be avoided.