Abstract

Aims

The aim of this study was to compare the effectiveness of a femoral nerve block and a periarticular infiltration in the management of early post-operative pain after total knee arthroplasty (TKA).

Intra-operative, peri-articular injection of local anaesthesia is an increasingly popular way of controlling pain following total knee replacement. At the same time, the problems associated with allogenic blood transfusion have led to interest in alternative methods for managing blood loss after total knee replacement, including the use of auto-transfusion of fluid from the patient’s surgical drain. It is safe to combine peri-articular infiltration with auto-transfusion from the drain. We performed a randomised clinical trial to compare the concentration of local anaesthetic in the blood and in the fluid collected in the knee drain in patients having either a peri-articular injection or a femoral nerve block. Clinically relevant concentrations of local anaesthetic were found in the fluid from the drains of patients having peri-articular injections (4.92 μg/ml (sd 3.151)). However, none of the patients having femoral nerve blockade had detectable levels. None of the patients in either group had clinically relevant concentrations of local anaesthetic in their blood after re-transfusion.

The evidence from this study suggests that it is safe to use peri-articular injection in combination with auto-transfusion of blood from peri-articular drains during knee replacement surgery.

Background

The relationship between obesity and cauda equina syndrome (CES) has not been previously evaluated or defined.

Introduction: Microfracture is found to be effective for isolated chondral defect of knee in young adults however controversy exists over the relevance of microfracture treatment in degenerative knee. The purpose of the study is to assess the outcome and patient satisfaction with the arthroscopic microfracture of osteoarthritic knee.

Materials: We collected the demographic details of the patient, weight, procedure and follow up details from June 2000 to Dec 2002. We reviewed the case notes retrospectively and assessed the patient satisfaction with Oxford knee score and Lysholm score.

Results: There were total of 194 patients but only 76 patients returned the questionnaire. The average patient age was 57 years (range: 27–87 years) with majority of the patients being male patients (43 patients). The average weight of the patient was 82 kg (44–119) and the mean duration of operation was 28 minutes. The patients were evaluated at an average follow-up of 51 months (range: 36–66 months). The average Lysholm score was 49 (4–100) with mean oxford score of 32.5(13–56).

21 patients required knee replacement at an average of 24 months (range: 6–48 months) from the initial microfracture. 17 out of 21 patients had kissing lesion and all showed grade 4 degenerative changes

Discussion: Age and weight does not appear to have any effect on microfracture treatment however more number of female patients seem to have more kissing lesion and poor result. With shorter duration of operation and proper explanation to patient give short term symptomatic relief before replacement surgery. It is worth considering this treatment for isolated grade 4 lesion or less than grade 4 degenerative chondral lesions in appropriately selected patients.

Introduction: Patients’ demands from hip arthroplasty are changing. Bigger bearings with alternative bearing surfaces are marketed to meet these demands. The aim of this study is to investigate the level of function achieved by patients with the larger hard-on-hard hip replacements in the short term.

Methods: Three groups of patients were identified from the arthroplasty register. The two study groups were those who received a 36mm ceramic-on-ceramic hip replacement (28 patients) and those who received larger metal-on-metal hip replacements (56 patients). The control group (25 patients) was age matched patients receiving 28mm hip replacements with a polyethylene acetabular component.

All patients received postal questionnaires comprising the Oxford Hip Score, the HOOS score and a satisfaction score. Routine yearly radiological examination was also undertaken. Demographic data are shown in Table 1.

Results: All three groups showed significant improvement in the oxford hip score after hip arthroplasty. Those with the larger head sizes had significantly lower scores than those with 28mm.

Activity scores in the HOOS hip survey were not significantly different in the three groups.

There was no difference in satisfaction scores and whether patients would have the same operation again.

Discussion: Our findings suggest that in the short term, functional levels achieved following hip replacement are not influenced by the size of bearing. Should these results be reproduced in larger and longer term studies use of these costly implants may have to be questioned.