Unicompartmental knee replacement for patients with partial thickness cartilage loss in the affected compartment

It is recommended that in medial compartment osteoarthritis (OA) unicompartmental knee replacement (UKR) should not be undertaken unless there is bone on bone. This recommendation is not evidence based and it is important to know if it is correct as there are many patients with pain and partial thickness cartilage loss (PTCL) who could potentially benefit from UKR. The aim of this study was to determine if the recommendation is valid. From our database of over 1000 patients treated with the Oxford UKR, we identified 29 with medial OA that had PTCL, confirmed at operation, but otherwise satisfied the recommended indications. This group was matched with 29 knees that had bone exposed (BE) on both sides of the medial compartment and 29 knees that had bone loss (BL) on both sides of the medial compartment. There was no significant difference in the demographics or preoperative scores between the three groups. At a mean follow up of 2 years (range 1-6) the Oxford Knee Score (OKS) of the PTCL group (mean 36 SD 10) was significantly (p < 0.001) worse than the OKS of either the bone exposed group (mean 43 SD 4) or the bone loss group (mean 43 SD 5). 21% of those with PTCL did not benefit substantially from the operation (increase in OKS ≤ 6), whereas all patients in the other groups did. We conclude that the results of UKR for PTCL are unpredictable and therefore that UKR should only be done for medial compartment OA if there is bone on bone. There is a need to develop a method to identify which patients with PTCL will do well so that this subgroup could be treated with UKR.

Minimally invasive Oxford phase 3 unicompartmental knee replacement: results of 1000 cases

This prospective study describes the outcome of the first 1000 phase 3 Oxford medial unicompartmental knee replacements (UKRs) implanted using a minimally invasive surgical approach for the recommended indications by two surgeons and followed up independently. The mean follow-up was 5.6 years (1 to 11) with 547 knees having a minimum follow-up of five years. At five years their mean Oxford knee score was 41.3 (sd 7.2), the mean American Knee Society Objective Score 86.4 (sd 13.4), mean American Knee Society Functional Score 86.1 (sd 16.6), mean Tegner activity score 2.8 (sd 1.1). For the entire cohort, the mean maximum flexion was 130° at the time of final review. The incidence of implant-related re-operations was 2.9%; of these 29 re-operations two were revisions requiring revision knee replacement components with stems and wedges, 17 were conversions to a primary total knee replacement, six were open reductions for dislocation of the bearing, three were secondary lateral UKRs and one was revision of a tibial component. The most common reason for further surgical intervention was progression of arthritis in the lateral compartment (0.9%), followed by dislocation of the bearing (0.6%) and revision for unexplained pain (0.6%). If all implant-related re-operations are considered failures, the ten-year survival rate was 96% (95% confidence interval, 92.5 to 99.5). If only revisions requiring revision components are considered failures the ten-year survival rate is 99.8% (confidence interval 99 to 100). This is the largest published series of UKRs implanted through a minimally invasive surgical approach and with ten-year survival data. The survival rates are similar to those obtained with a standard open approach whereas the function is better. This demonstrates the effectiveness and safety of a minimally invasive surgical approach for implanting the Oxford UKR.

Constitutional translocation breakpoint mapping by genome-wide paired-end sequencing identifies HACE1 as a putative Wilms tumour susceptibility gene

BACKGROUND

Localisation of the breakpoints of chromosomal translocations has aided the discovery of several disease genes but has traditionally required laborious investigation of chromosomes by fluorescent in situ hybridisation approaches. Here, a strategy that utilises genome-wide paired-end massively parallel DNA sequencing to rapidly map translocation breakpoints is reported. This method was used to fine map a de novo t(5;6)(q21;q21) translocation in a child with bilateral, young-onset Wilms tumour.

METHODS AND RESULTS

Genome-wide paired-end sequencing was performed for approximately 6 million randomly generated approximately 3 kb fragments from constitutional DNA containing the translocation, and six fragments in which one end mapped to chromosome 5 and the other to chromosome 6 were identified. This mapped the translocation breakpoints to within 1.7 kb. Then, PCR assays that amplified across the rearrangement junction were designed to characterise the breakpoints at sequence-level resolution. The 6q21 breakpoint transects and truncates HACE1, an E3 ubiquitin-protein ligase that has been implicated as a somatically inactivated target in Wilms tumourigenesis. To evaluate the contribution of HACE1 to Wilms tumour predisposition, the gene was mutationally screened in 450 individuals with Wilms tumour. One child with unilateral Wilms tumour and a truncating HACE1 mutation was identified.

CONCLUSIONS

These data indicate that constitutional disruption of HACE1 likely predisposes to Wilms tumour. However, HACE1 mutations are rare and therefore can only make a small contribution to Wilms tumour incidence. More broadly, this study demonstrates the utility of genome-wide paired-end sequencing in the delineation of apparently balanced chromosomal translocations, for which it is likely to become the method of choice.

The role of foot and ankle assessment of patients with lower limb osteoarthritis

OBJECTIVES

Physiotherapists do not routinely examine the feet of patients with lower limb osteoarthritis, and there is no widely used tool for measuring foot posture. However, differences in foot posture have been demonstrated between patients with medial compartment osteoarthritis of the knee and osteoarthritis of the hip, and guidelines for managing these patients include interventions such as orthotics which presume foot assessment. This study considers a new clinical tool, the Foot Posture Index (FPI). It examines its utility in a physiotherapy outpatient setting with a cohort of patients with medial compartment osteoarthritis of the knee and osteoarthritis of the hip, and investigates the relationship of FPI scores with the range of dorsiflexion of the ankle.

DESIGN

Cross-sectional observational study.

SETTING

A specialist orthopaedic hospital.

PARTICIPANTS

In total, there were 60 participants: 20 patients with medial compartment osteoarthritis of the knee, 20 patients with osteoarthritis of the hip, and a control group of 20 age-matched healthy volunteers.

OUTCOME MEASURES

A single measurement of the FPI and range of dorsiflexion.

RESULTS

Significant differences in FPI scores and range of dorsiflexion were seen between groups. On average, patients with osteoarthritis of the hip had more supinated, plantarflexed feet, and patients with medial compartment osteoarthritis of the knee had pronated feet. Healthy controls fell within the normal range. Patients with osteoarthritis of the hip had a median FPI score of -4.5, patients with medial compartment osteoarthritis of the knee had a median FPI score of 7.0, and the healthy controls had a median FPI score of 1.0. The median difference in FPI scores between patients with osteoarthritis of the hip and medial compartment osteoarthritis of the knee was 12 [95% confidence interval (CI) 10 to 13]; between patients with osteoarthritis of the hip and the healthy group was 6 (95% CI 3 to 9); and between patients with medial compartment osteoarthritis of the knee and the healthy group was 5 (95% CI 3 to 8). The median difference in dorsiflexion scores between patients with osteoarthritis of the hip and medial compartment osteoarthritis of the knee was 10 degrees (95% CI 8 to 15); between patients with osteoarthritis of the hip and the healthy group was 10 degrees (95% CI 7 to 15); and between patients with medial compartment osteoarthritis of the knee and the healthy group was 0 degrees (95% CI -3 to 5). Foot posture and range of dorsiflexion were moderately positively correlated (rho 0.57), with pronated feet having a greater range of dorsiflexion.

CONCLUSION

The FPI is sufficiently sensitive to measure differences in foot posture of patients with medial compartment osteoarthritis of the knee and osteoarthritis of the hip, and is easy to use. Accurate foot assessment is useful as foot postures may be influenced by specific physiotherapy treatment modalities and orthotic interventions.

A novel gel-based method for self-collection and ambient temperature postal transport of urine for PCR detection of Chlamydia trachomatis

OBJECTIVES

The aim of this study was to develop a novel urine transport method to be used in self-collection-based screening for Chlamydia trachomatis. The method needed to be suitable for C trachomatis PCR detection, be economical and suitable for transport by standard envelope mailing.

METHODS

An anhydrous gel composed of super-absorbent polymer and buffering agent was used to desiccate urine into a dry granulous state, which could subsequently be reconstituted upon arrival at a laboratory. DNA was then extracted from the reconstituted solution using the Roche MagNA Pure protocol for the detection of C trachomatis by PCR. Collections of urine specimens from three populations with widely differing chlamydia prevalence (100%,n = 56; 47%, n = 70; 3%, n = 97) were used. We determined the gel method's impact on C trachomatis PCR sensitivity and specificity using neat and gel-processed urine specimens. An equine herpes virus PCR was used to test for assay inhibition.

RESULTS

Overall, the sensitivity of the gel-based method ranged from 94.6-100% compared with neat urine, with a specificity of 100%. No PCR inhibition or decrease in analytical sensitivity was observed using the gel-processed extracts.

CONCLUSIONS

The gel-based method was found to be suitable for the detection of C trachomatis by PCR. In addition, its ease of use, effectiveness at ambient temperature and low cost makes it well-suited for self-collection kits used in population-based C trachomatis screening, particularly for geographically and socially isolated individuals.

Development of a method for detection of Giardia duodenalis cysts on lettuce and for simultaneous analysis of salad products for the presence of Giardia cysts and Cryptosporidium oocysts

We report a method for detecting Giardia duodenalis cysts on lettuce, which we subsequently use to examine salad products for the presence of Giardia cysts and Cryptosporidium oocysts. The method is based on four basic steps: extraction of cysts from the foodstuffs, concentration of the extract and separation of the cysts from food materials, staining of the cysts to allow their visualization, and identification of cysts by microscopy. The concentration and separation steps are performed by centrifugation, followed by immunomagnetic separation using proprietary kits. Cyst staining is also performed using proprietary reagents. The method recovered 46.0% +/- 19.0% (n = 30) of artificially contaminating cysts in 30 g of lettuce. We tested the method on a variety of commercially available natural foods, which we also seeded with a commercially available internal control, immediately prior to concentration of the extract. Recoveries of the Texas Red-stained Giardia cyst and Cryptosporidium oocyst internal controls were 36.5% +/- 14.3% and 36.2% +/- 19.7% (n = 20), respectively. One natural food sample of organic watercress, spinach, and rocket salad contained one Giardia cyst 50 g(-1) of sample as an indigenous surface contaminant.

46. INNOVATION AND DESIGN: IMPROVING CONTACT TRACING IN SEXUAL HEALTH CLINICS

Contact tracing (CT) is an integral part of sexually transmitted infection (STI) management. Although routinely conducted in most sexual health clinics (SHCs), the methods used may vary. To improve CT required novel approaches. First we audited the outcomes of current contact tracing methods. A major finding of this audit was that while CT was routinely recommended, outcomes were poorly recorded. We developed a sticker to be placed in the charts of clients with a traceable STI. This indicated the number of contacts requiring notification, and how many had been notified and treated at our clinic. This enabled a standardised approach to CT records and improved ability to audit outcomes. It also focused clinicians on the need to ensure followup of CT and to offer assistance when CT had not been done. Next, a brochure was developed to give to clients when diagnosed with a traceable STI. This brochure mentioned the reasons for contacting patterns, dispelled some myths that have been found in previous studies about telling partners and provided ideas about how to tell partners. In conjunction with this a SMS was developed, that could be sent to index cases' mobile phones, allowing them to forward the SMS to partners. This was seen as an ideal method for young people who frequently had mobile numbers of past partners but little other contact details. It was also able to be simple and quick. The next step will be reauditing the CT outcomes once the SMS and brochure are in established use.

Towards standard methods for the detection of Cryptosporidium parvum on lettuce and raspberries. Part 2: validation

We report the results of interlaboratory collaborative trials of methods to detect oocysts of the protozoan parasite Cryptosporidium parvum on lettuce and raspberries. The trials involved eight expert laboratories in the United Kingdom. Samples comprised 30 g lettuce, and 60 g raspberries. Lettuce samples were artificially contaminated at three levels: low (8.5-14.2 oocysts), medium (53.5-62.6 oocysts), and high (111.3-135.0 oocysts). Non-contaminated lettuce samples were also tested. The method had an overall sensitivity (correct identification of all artificially contaminated lettuce samples) of 89.6%, and a specificity (correct identification of non-contaminated samples) of 85.4%. The total median percentage recovery (from all artificially contaminated samples) produced by the method was 30.4%. The method was just as reproducible between laboratories, as repeatable within a laboratory. Raspberry samples were artificially contaminated at three levels: low (8.5-26.8 oocysts), medium (29.7-65.7 oocysts), and high (53.9-131.3 oocysts). Non-contaminated raspberry samples were also tested. The method had an overall sensitivity (correct identification of all artificially contaminated raspberry samples) of 95.8%, and a specificity (correct identification of non-contaminated samples) of 83.3%. The total median percentage recovery (from all artificially contaminated samples) produced by the method was 44.3%. The method was just as reproducible between laboratories, as repeatable within a laboratory. The results of the collaborative trial indicate that these assays can be used effectively in analytical microbiological laboratories.

Towards standard methods for the detection of Cryptosporidium parvum on lettuce and raspberries. Part 1: development and optimization of methods

No standard method is available for detecting protozoan parasites on foods such as soft fruit and salad vegetables. We report on optimizing methods for detecting Cryptosporidium parvum on lettuce and raspberries. These methods are based on four basic stages: extraction of oocysts from the foodstuffs, concentration of the extract and separation of the oocysts from food materials, staining of the oocysts to allow their visualization, and identification of oocysts by microscopy. The concentration and separation steps are performed by centrifugation, followed by immunomagnetic separation using proprietary kits. Oocyst staining is also performed using proprietary reagents. The performance parameters of the extraction steps were extensively optimized, using artificially contaminated samples. The fully developed methods were tested several times to determine their reliability. The method to detect C. parvum on lettuce recovered 59.0+/-12.0% (n=30) of artificially contaminated oocysts. The method to detect C. parvum on raspberries recovered 41.0+/-13.0% (n=30) of artificially contaminated oocysts.

The Oxford medial unicompartmental knee replacement using a minimally-invasive approach

This prospective study describes the complications and survival of the first 688 Phase 3 Oxford medial unicompartmental knee replacements implanted using a minimally-invasive technique by two surgeons and followed up independently. None was lost to follow-up. We had carried out 132 of the procedures more than five years ago. The clinical assessment of 101 of these which were available for review at five years is also presented. Nine of the 688 knees were revised: four for infection, three for dislocation of the bearing and two for unexplained pain. A further seven knees (1%) required other procedures: four had a manipulation under anaesthesia, two an arthroscopy and one a debridement for superficial infection. The survival rate at seven years was 97.3% (95% confidence interval 5.3). At five years, 96% of the patients had a good or excellent American Knee Society score, the mean Oxford knee score was 39 and the mean flexion was 133 degrees. This study demonstrates that the minimally-invasive Oxford unicompartmental knee replacement is a reliable and effective procedure.

The relative significance of preoperative oral antibiotics, mechanical bowel preparation, and preoperative peritoneal contamination in the avoidance of sepsis after radical surgery for ulcerative colitis and Crohn's disease of the large bowel

This paper reports the results of a prospective, random, controlled study of two régimes of preparation of the bowel in 100 patients undergoing elective radical surgery for non-specific inflammatory disease of the colon.

Every patient received identical dietary preparation for surgery. No aperients or enemas were given in view of the inflamed state of the bowel. All patients received phthalylsulphathiazole, and in addition 50 patients chosen at random were given Colomycin. The two groups who did or did not receive Colomycin were well matched in respect of age, sex, type of operation, and steroid therapy.

The addition of Colomycin to the standard régime of mechanical preparation and sulphonamides conferred no benefit to the patient in terms of postoperative complication rates. However, significantly increased rates of wound sepsis and paralytic ileus were found in patients who had a loaded colon at laparotomy or in whom faecal contamination of the peritoneal cavity occurred during operation.

These results suggest that antibiotic sterilization of the large bowel, whatever its intrinsic merits, is no substitute for adequate mechanical preparation and meticulous attention to surgical technique.

Reliability and responsiveness of the shuttle walking test in patients with chronic low back pain

BACKGROUND AND PURPOSE

Walking is an important functional activity and the shuttle walking test has been shown to be a useful test for patients with chronic airways obstruction and heart failure. The test has been used in low back pain research over recent years and has increasingly been used as an outcome measure to investigate treatment efficacy in patients with low back pain. The aim of the present study was to determine the reliability and responsiveness of the shuttle walking test within a group of patients with low back pain (with or without sciatica).

METHOD

Reliability of the shuttle walking test was determined on a group of patients with low back pain (n = 44) using the Bland and Altman (1986) limits of agreement and the intraclass correlation coefficient (ICC). Responsiveness was assessed using the standardized effect size. The mean distance walked within a patient population (n = 337) was compared with an age- and sex-matched group of healthy subjects (n = 122).

RESULTS

The shuttle walking test obtained an ICC score of 0.99, whereas the limits of agreement test gave a mean difference of 2.5 m with upper and lower limits of agreement of 52 m and -47 m, respectively. Patients undertaking fitness training reached an effect size of 1.2 compared to a control group of 0.23 and 0.94 for a group undergoing various orthopaedic treatments.

CONCLUSIONS

The present study has shown that the shuttle walking test is a reliable and responsive test within a group of patients with low back pain, with or without sciatica. It is simple to administer and provides a quick method of measuring one aspect of a patient's physical function.

Localization of a gene (MCUL1) for multiple cutaneous leiomyomata and uterine fibroids to chromosome 1q42.3-q43

Dominant transmission of multiple uterine and cutaneous smooth-muscle tumors is seen in the disorder multiple leiomyomatosis (ML). We undertook a genomewide screen of 11 families segregating ML and found evidence for linkage to chromosome 1q42.3-q43 (maximum multipoint LOD score 5.40). Haplotype construction and analysis of recombinations permitted the minimal interval containing the locus, which we have designated "MCUL1," to be refined to an approximately 14-cM region flanked by markers D1S517 and D1S2842. Allelic-loss studies of tumors indicated that MCUL1 may act as a tumor suppressor. Identification of MCUL1 should have wide interest, since this gene may harbor low-penetrance variants predisposing to the common form of uterine fibroids and/or may undergo somatic mutation in sporadic leiomyomata.

Time and cost analysis of repacking medications in unit-of-use containers

OBJECTIVES

To evaluate the effects of repacking drugs in unit-of-use containers in community pharmacies. The purpose of this study was to examine whether unit-of-use repacking reduces routine mechanical "counting and pouring" to allow more time for pharmaceutical care.

DESIGN

Simulation pilot study to evaluate the differences between the existing and proposed systems. Based on the literature, four variables--optimum pack size, time savings, packaging costs, and shelving requirements--were selected for evaluation. Historical prescription data from a chain were used in determining the sample drugs and their optimum pack sizes. Workflow analysis and time study were used to estimate the time savings. Manufacturer bottles, repack bottles, and shelves were measured to determine the impact of using unit-of-use containers on storage requirements.

SETTING

Three community pharmacies in a major drugstore chain in Cincinnati, Ohio.

RESULTS

The 25 fastest-moving solid oral dosage forms, representing 21.6% of all drugs dispensed by the chain, were selected as the sample drugs for the study. The workflow analysis and time study revealed that 0.79 minutes could be saved per prescription if repacked drugs were used. There was an increased cost of approximately $0.05 for every repack bottle used in place of a prescription vial. It was calculated that repacking in unit-of-use containers would increase storage requirements in the pharmacy by 2.5 times if current inventory levels were maintained.

CONCLUSION

Repacking drugs in unit-of-use containers is potentially an inexpensive method to increase usable time in the pharmacy that does not require an increase in personnel or the purchase of additional technology at the store level.