Introduction

The PACE trial was the first randomized controlled trial (RCT) investigating the efficacy of paracetamol in acute low back pain. Non-compliance to study medication was considered to be a limitation of this RCT. In contrast to conventional statistical methods, complier average causal effects (CACE) analysis may provide unbiased estimates of the effects for participants compliant to paracetamol.

Introduction: The use of extendible endoprosthetic implants in the skeletally immature has been used for just under 30 years. Limb salvage has become a realistic alternative to those children presenting with primary bone sarcomas. We aim to review the use of an implant which uses a non-invasive mechanism of adjusting the length of the prosthesis, during the growth phase.

Method: A retrospective review of consecutive patients undergoing primary or revision endoprosthetic replacement with non-invasive extensible implants, was undertaken. Between January 1993 and February 2008, 34 children were treated with non-invasive extensible endoprosthetic replacements, 26 distal femur, 5 total femurs, 3 proximal tibias and 1 proximal femur.

Results: The underlying pathology, requiring excision, was Ewings sarcoma in 4 patients and osteosarcoma in the remaining 30 patients. Most underwent pre-operative chemotherapy and 2 patients died of their disease.

Four operations were secondary procedures following previous non-grower implant failures (1 infection of previous EPR, 1 IM nail non-union, 1 failed allograft and a revision of a proximal femoral EPR to a total femoral prosthesis). Five patients required revision of the primary prosthesis (2 with motor failures, 3 due to prosthesis infections).

Mean time to start lengthening from surgery was 12.2 months. The mean number of lengthenings was 4 with an average total length of 30 mm achieved, mean leg length difference was 0.8 cm. All lengthenings were undertaken with the patient fully alert, no adverse incidents occurred at the time or after lengthening.

Discussion: The non-invasive prostheses show promise in handling the difficult problem of limb preservation in a growing child, with similar complication rates to that of an invasive type, but without the need for multiple anaesthetics for lengthening.

Measurement of the rate of fracture healing is a major problem in fracture research. Bone mineral density (BMD) of fracture callus has been used as a measure of healing in diaphyseal fractures. However, metaphyseal fractures (especially in the elderly) are now the commonest type of fracture and are a significant public health problem. This study investigated whether measurement of BMD at the fracture site in the distal radius can be used as a measure of fracture healing.

We recruited 28 patients who had sustained a dorsally displaced distal radial fracture which was deemed to require treatment by intrafocal wire fixation. All patients had acceptable correction of dorsal and radial angle at final x ray (3 months). Wrist function was measured using the Patient Rated Wrist Evaluation (PRWE – a validated outcome measure for use after distal radial fractures), grip strength,and range of motion. All measurements were made at 6, 12 and 26 weeks. BMD was measured at the fracture site (examining the BMD of the medullary bone at the fracture site after removal of wires), in the opposite wrist and the lumbar spine using QCT at 6 weeks after fracture.

There was no correlation between fracture site BMD and BMD at the other wrist or the lumbar spine (r < 0.3). The BMD at the fracture site was higher than the BMD at the other wrist (mean 168 vs 70 HU; p< 0.001 paired T test). There was no relationship between fracture site BMD or the ratio of BMDs fracture site / normal wrist, and any of the functional assessments (proportion grip strength recovered, range of motion or PRWE (r < 0.3)).

15 of these patients underwent a second QCT at 12 weeks after fracture. There was no significant change in fracture site BMD between the first and second scan.

These data indicate that fracture site BMD is unlikely to be a useful method of measuring metaphyseal bone healing. The increase in BMD at the fracture site was unexpected; possible explanations include impaction of bone or high BMD in woven bone (the relationship of which to bone stiffness is uncertain).

Older fracture patients frequently ask whether their osteoporosis will affect fracture healing. There is only limited previous data about this. We investigated recovery after distal radial fracture, and compared it with BMD of the other distal radius and the lumbar spine (measured using quantitative CT).

All 28 patients had sustained a dorsally displaced distal radial fracture which was deemed to require treatment by intrafocal wire fixation. All patients had acceptable correction of dorsal and radial angle at final x ray (3 months). Wrist function was measured using the Patient Rated Wrist Evaluation (PRWE – a validated outcome measure for use after distal radial fractures), grip strength,and range of motion. All measurements were made at 6, 12 and 26 weeks. BMD was measured in the opposite wrist and the lumbar spine using QCT at 6 weeks after fracture.

There was no correlation between recovery of grip strength (% of contralateral grip strength) at 6,12,or 26 weeks with BMD at either site. Similarly, there was no correlation between BMD and either absolute PRWE scores at any time point or improvement in PRWE between time points. The strongest predictor of recovery of grip appeared to be the proportion of grip recovered at 6 weeks (correlation between% grip recovered at 6 weeks and 3 months r = 0.85; at 6 weeks and 6 months r= 0.56; both p < 0.001). This was not affected by age or variations in measured final dorsal or radial angles or length within this group. It was not affected by degree of preoperative fracture displacement.

These data suggest that recovery of function after distal radial fractures is not influenced by osteoporosis. The data about the importance of initial recovery of grip suggest that factors other than bone position and bone healing may affect rate of functional recovery after distal radial fracture.

The purpose of the study was to determine the percentage of knowledge retained immediately following an outpatient consultation for total hip and knee joint arthroplasty, and whether any improvement in that knowledge occurred after reading an information leaflet about the operation. Patients who were placed on the waiting list for joint replacement surgery, were verbally given information during the consultation about basic operative details, post-operative programme, and potential complications. A questionnaire was completed asking them to recall these details. Information leaflets were then given to them to read. 6 weeks later they were again contacted and asked the same questions.

Immediately following a consultation, patients recall only a small percentage of information. In particular, retention of post-operative recovery time frames (51–63%), and possible operative complications (0–61 %). Despite an information booklet, their level of knowledge deteriorates from the initial consultation. Verbal and written information supplied to a patient, may be understood, but it is easily and quickly forgotten. In an increasingly medico-legal environment it is essential to gain an informed consent from a patient when performing interventions. The provision of an information booklet may provide nothing more than proof for the surgeon of information provision to the patient.

Introduction: The natural history of bone bruises of the knee and their clinical significance remains unclear with only a few short term studies in the literature.

Aim: This study was designed to try and elucidate the long term outcome of bone bruises of the knee following trauma.

Materials and Methods: 60 patients with bone bruises identified in their knees by MRI scans following trauma were included in the study. All patients were reviewed in a research clinic with a minimum 5 year follow up. A detailed history including mechanism of injury, persistent symptoms and functional status was obtained. Clinical examination to identify intra-articular pathology was then undertaken. All patients had a repeat MRI scan of the knee. The relationship between the injury and the bone bruise, the effect of treatment if any and the long term outcome of such lesions was studied.

Results: 80% of the patients had a twisting injury with our without a hyperextension of valgus/varus force. 58% of our series had ACL injuries and 68% of the bone bruises were in the medial condyle. 72% of the patients did not return to their pre-accident status and had continuing symptoms although the majority of them did not have signs of clinical instability. There was MRI evidence of lasting sequelae of bone bruises in the majority of patients. Detailed results will be discussed.

Conclusions: bone bruises identified on MRI following trauma to the knee are significant lesions with the potential for long term sequelae.

We investigated the implant-bone interface around one design of femoral stem, proximally coated with either a plasma-sprayed porous coating (plain porous) or a hydroxyapatite porous coating (porous HA), or which had been grit-blasted (Interlok). Of 165 patients implanted with a Bimetric hip hemiarthroplasty (Biomet, Bridgend, UK) specimens were retrieved from 58 at post-mortem.

We estimated ingrowth and attachment of bone to the surface of the implant in 21 of these, eight plain porous, seven porous HA and six Interlok, using image analysis and light morphometric techniques. The amount of HA coating was also quantified.

There was significantly more ingrowth (p = 0.012) and attachment of bone (p > 0.05) to the porous HA surface (mean bone ingrowth 29.093 ± 2.019%; mean bone attachment 37.287 ± 2.489%) than to the plain porous surface (mean bone ingrowth 21.762 ± 2.068%; mean bone attachment 18.9411 ± 1.971%). There was no significant difference in attachment between the plain porous and Interlok surfaces. Bone grew more evenly over the surface of the HA coating whereas on the porous surface, bone ingrowth and attachment occurred more on the distal and medial parts of the coated surface. No significant differences in the volume of HA were found with the passage of time.

This study shows that HA coating increases the amount of ingrowth and attachment of bone and leads to a more even distribution of bone over the surface of the implant. This may have implications in reducing stress shielding and limiting osteolysis induced by wear particles.