A patient's recollection of pre-operative status is not accurate one year after arthroplasty of the hip or knee.

If patients could recall their physical status before total hip (THA) or knee arthroplasty (TKA) accurately it could have valuable applications both clinically and for research. This study evaluated the accuracy of a patient's recollection one year after either THA or TKA using the Oxford hip or knee scores (OHS and OKS). In total, 113 patients (59 THA, 54 TKA) who had completed the appropriate score pre-operatively were asked to complete the score again at a mean of 12.4 months (standard deviation (sd) 0.8) after surgery, recalling their pre-operative state. While there were no significant differences between the actual and recalled pre-operative scores (OHS mean difference 0.8, sd 6.21, 95% confidence interval (CI) -0.82 to 2.42, p = 0.329; OKS mean difference -0.11, sd 7.34, 95% CI -2.11 to 1.89, p = 0.912), absolute differences were relatively large (OHS, 5.24; OKS, 5.41), correlation was weak (OHS r = 0.7, OKS r = 0.61) and agreement between actual and recalled responses for individual questions was poor in half of the OHS and two thirds of the OKS. A patient's recollection of pre-operative pain and function is inaccurate one year after THA or TKA.

Contamination of banked femoral head allograft: incidence, bacteriology and donor follow up.

BACKGROUND: Allograft donations are not uncommonly found to be contaminated. The issue of contaminated donations from live donors at the time of surgery, and the significance of this to the patient in terms of subsequent sepsis of the arthroplasty, were examined. METHODS: The donations of femoral heads to the Queensland Bone Bank over a 9-year period were reviewed, and the incidence and bacteriology of contamination were detailed. Clinical outcomes were determined for donors who had positive cultures at the time of retrieval and they were compared with those of culture-negative donors. RESULTS: Between March 1987 and February 1996, 232 femoral heads were donated to the Queensland Bone Bank. Four specimens were sent for culture with each femoral head (surface swab of femoral head, acetabular swab, bone biopsy and capsule). In 51 cases, one or more positive cultures were obtained (22% contamination rate). The majority of organisms cultured were Staphylococcus epidermidis. One hundred and seventy donations came from surgery performed at the Princess Alexandra Hospital, and 40 femoral heads were considered contaminated. Deep infection was recorded in one of the 40 cases with contaminated donations and three out of 130 non-contaminated donations had subsequent septic episodes. CONCLUSION: The contamination rate detailed in the present report is higher than in most series. This may be due to the fact that four bacteriological specimens are taken to assess contamination. Two of these specimens are tissue samples which yielded more positive results than did the two swabs. All other series take no more than two bacteriological specimens, which are usually bone swabs. These are shown to have a poor yield of positive cultures. Therefore there is a significant underestimation of contamination rates by other bone banks. This has implications for the recipients of bone from those banks, particularly when the allograft material is not secondarily sterilized. This is important given increasing allograft usage, and the increasing numbers of revision joint arthroplasty and impaction grafting procedures being performed. Sterilization of all bone by irradiation to 25 kGy is recommended.

Poor results of the Freeman uncemented metal-backed acetabular component. Five-to-nine-year results.

We reviewed 120 consecutive primary total hip replacements in 109 patients in whom a Freeman uncemented metal-backed component had been used. Acetabular components were used with a Freeman neck-retaining stem in one of three configurations: cemented smooth stem, uncemented smooth stem or uncemented ridged stem. After a mean follow up of 72 months (62 to 113) there were nine cases of aseptic loosening; a survivorship at eight years of 83%. In addition, more than one-third of the remaining surviving cups showed loosening radiologically. The Freeman acetabular component demonstrated a characteristic pattern of loosening on radiographs. The high incidence of aseptic loosening can be explained by poor design and material failure.

The medium-term results of a cemented Freeman femoral neck-retaining prosthesis.

We have reviewed 202 consecutive primary hip replacements using a Freeman cemented femoral component after a mean period of follow-up of 64 months (23 to 113). There was only one revision for aseptic loosening. Retention of the femoral neck may act to reduce the torsional and shear forces at the implant-cement interface and may provide a seal against the migration of polyethylene-laden joint fluid in the potential joint space. The cemented Freeman femoral component with retention of the femoral neck was successful for up to nine years.

Bacterial contamination rates during bone allograft retrieval.

A retrospective study of allograft bone retrieved from 401 donors between January 1987 and March 1996 was performed to determine the incidence of bacterial contamination. Contamination according to type of donor (live, multiorgan, cadaveric) was also determined. Live donors donating a femoral head demonstrated a contamination rate of 13%; multiorgan donors, 24%; and cadaveric donors, 35%. Donor contamination by type of bone (hemipelvis, femur, tibia) showed no significant difference in the multiorgan donors. In cadaveric donors, there was a significant increase in contamination of the hemipelves as compared to the femur and tibias. Recommendations for contamination control in allograft retrieval are given. Our findings are of great significance for musculoskeletal banks that do not secondarily irradiate and rely on screening of allograft bone for contamination alone.

Hyaluronidase (Hyalase): a useful addition in haematoma block?

OBJECTIVE: To investigate whether hyaluronidase (Hyalase) is a useful and justified addition to haematoma block for pain relief. METHODS: The study was a randomised double blind trial of 33 consecutive patients attending the accident and emergency department for manipulation of distal radius fracture under haematoma block. Control patients received 1% lignocaine; the treatment group received 1% lignocaine plus 1500 IU hyaluronidase. Manipulation occurred 10 minutes after instituting the block. RESULTS: 16 patients received hyaluronidase, 17 received lignocaine only. One patient with unsuccessful manipulation was excluded. There was no significant difference between the two groups for any of three methods of pain assessment (P > 0.05, Mann Whitney). CONCLUSIONS: The addition of hyaluronidase does not increase the efficacy of the haematoma block when 10 minutes are allowed to elapse before manipulation, and the increased cost of adding (and risk of allergy) is not justified by any theoretical increased speed of analgesia.

Unreamed intramedullary tibial nailing--fatigue of locking bolts.

Between January 1990 and October 1993 we investigated 72 consecutive patients who had an unreamed tibial nail inserted for fractures of the tibial shaft; 75 per cent (N = 54) were closed fractures and 25 per cent (N = 18) were open fractures. The mean follow up was 15.2 months. Of the patients 91.7 per cent (N = 66) were interlocked, 58 per cent (N = 38) statically and 42 per cent (N = 28) dynamically. Union rate was 98.6 per cent, time to union was 18.5 weeks, 17.3 weeks for closed fractures, 22 weeks for open fractures. Shortening greater than 1 cm occurred in 1.4 per cent (N = 1), varus and valgus deformity in 4.1 per cent each (N = 3). There was no rotational deformity. Of the locking bolts 30 per cent broke 8-10 weeks after partial weight bearing was allowed. Electron microscopy investigations showed that failure of the bolts was due to fatigue. It was not associated with any clinical problems with regard to union times or incidence of malunion. Bolt failure is however a problem if you try to remove the nail.

Paraplegia following a rivet gun injury: the use of magnetic resonance imaging in the management.

We describe the case of a 39-year-old man who was accidentally shot in the back by a rivet gun. This resulted in paraplegia and partial sensory loss. Magnetic resonance imaging (MRI) was helpful in the accurate localization of the foreign body and in the assessment of the spinal cord damage. MRI enabled accurate pre-operative localization of the rivet and provided information on the degree of damage to the spinal cord. The artefact produced on computed tomography plus the limited anatomical detail of the spinal cord in the absence of intrathecal contrast makes this technique unhelpful.

The risks of staying in London: a review of overseas visitors admitted to a London hospital.

A retrospective review of 103 acute admissions of overseas visitors to a central London hospital was performed. Admissions were most commonly due to infection (43 admissions) and to recurrence of preexisting disease (40 admissions). Patients over 60 years were frequently admitted with new diagnoses. Groups at risk of admission were identified and strategies to reduce admissions discussed.

Prolonged infection of human synovial cells with Ross River virus.

Primary cultures of human synovial cells shed infectious virus for 14 to 35 days following infection with isolates of Ross River virus which had been passaged in the C6/36 line of Aedes albopictus mosquito cells. No frank cytopathic effect was seen in infected synovial cells and they continued to replicate for the duration of the experiments.