Group sequential designs for pragmatic clinical trials with early outcomes: methods and guidance for planning and implementation

BACKGROUND

Group sequential designs are one of the most widely used methodologies for adaptive design in randomized clinical trials. In settings where early outcomes are available, they offer large gains in efficiency compared to a fixed design. However, such designs are underused and used predominantly in therapeutic areas where there is expertise and experience in implementation. One barrier to their greater use is the requirement to undertake simulation studies at the planning stage that require considerable knowledge, coding experience and additional costs. Based on some modest assumptions about the likely patterns of recruitment and the covariance structure of the outcomes, some simple analytic expressions are presented that negate the need to undertake simulations.

METHODS

A model for longitudinal outcomes with an assumed approximate multivariate normal distribution and three contrasting simple recruitment models are described, based on fixed, increasing and decreasing rates. For assumed uniform and exponential correlation models, analytic expressions for the variance of the treatment effect and the effects of the early outcomes on reducing this variance at the primary outcome time-point are presented. Expressions for the minimum and maximum values show how the correlations and timing of the early outcomes affect design efficiency.

RESULTS

Simulations showed how patterns of information accrual varied between correlation and recruitment models, and consequentially to some general guidance for planning a trial. Using a previously reported group sequential trial as an exemplar, it is shown how the analytic expressions given here could have been used as a quick and flexible planning tool, avoiding the need for extensive simulation studies based on individual participant data.

CONCLUSIONS

The analytic expressions described can be routinely used at the planning stage of a putative trial, based on some modest assumptions about the likely number of outcomes and when they might occur and the expected recruitment patterns. Numerical simulations showed that these models behaved sensibly and allowed a range of design options to be explored in a way that would have been difficult and time-consuming if the previously described method of simulating individual trial participant data had been used.

Interventions for treating fractures of the distal femur in adults

BACKGROUND

Fractures of the distal femur (the far end of the thigh bone just above the knee) are a considerable cause of morbidity. Various different surgical and non-surgical treatments have been used in the management of these injuries but the best treatment remains unknown.

OBJECTIVES

To evaluate the benefits and harms of interventions for treating fractures of the distal femur in adults.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was October 2021.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials in adults comparing interventions for treating fractures of the distal femur. Interventions included surgical implants (retrograde intramedullary nail (RIMN), fixed-angle devices, non-locking plate fixation, locking plate, internal fixation, distal femoral replacement, mono-axial plates, poly-axial plates and condylar buttress plates) and non-surgical management.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our critical outcomes were validated patient-reported outcome measures (PROMs), direct adverse events, participant-reported quality of life (QoL) and pain scores. Our other important outcomes were adverse events indirectly related to intervention, symptomatic non-union, malunion and resource use. We used GRADE to assess certainty of evidence for each outcome.

MAIN RESULTS

We included 14 studies with 753 participants: 13 studies compared different surgical interventions, and one study compared surgical with non-surgical management. Here, we report the effects for RIMN compared with locking plates. Three studies (221 participants) reported this comparison; it included the largest study population and these are the two most commonly used devices in contemporary orthopaedic trauma practice. Studies used three different tools to assess PROMs. We found very-low certainty evidence for lower Disability Rating Index scores after RIMN at short-term follow-up favouring RIMN (mean difference (MD) -21.90, 95% confidence interval (CI) -38.16 to -5.64; 1 study, 12 participants) and low-certainty evidence of little or no difference at long-term follow-up (standardised mean difference (SMD) -0.22, 95% CI -0.50 to 0.06; 2 studies, 198 participants). Re-expressing the SMD of the long-term follow-up data to Knee Society Score (KSS) used by one study found no clinical benefit of RIMN, based on a minimal clinically important difference of 9 points (MD 2.47, 95% CI -6.18 to 0.74). The effect on QoL was very uncertain at four months (MD 0.01, 95% CI -0.42 to 0.44; 1 study, 14 participants) and one year (MD 0.10, 95% CI -0.01 to 0.21; 1 study, 156 participants); this evidence was very low certainty. For direct adverse events, studies reported reoperation, loss of fixation, superficial and deep infection, haematoma formation and implant loosening. Effects for all events were imprecise with the possibility of benefit or harm for both treatments. We considered reoperation the most clinically relevant. There was very low-certainty evidence of little or no difference in reoperation between the two implants (risk ratio (RR) 1.48, 95% CI 0.55 to 4.00; 1 study, 104 participants). No studies reported pain.  For other important outcomes, we noted that people treated with RIMN may be more likely to have varus/valgus deformity (RR 2.18, 95% CI 1.09 to 4.37; 1 study, 33 participants; low-certainty evidence). However, we found no evidence of any important differences between treatments in terms of bony union, indirect adverse events, or resource use. Other comparisons of surgical interventions included in the review were: RIMN versus single fixed-angle device (3 studies, 175 participants); RIMN versus non-locking plate fixation (1 study, 18 participants); locking plate versus single fixed-angle device (2 studies, 130 participants); internal fixation versus distal femoral replacement (1 study, 23 participants); mono-axial plates versus poly-axial plates (2 studies, 67 participants); mono-axial plate versus condylar buttress plate (1 study, 78 participants). The certainty of the evidence for outcomes in these comparisons was low to very low, and most effect estimates were imprecise.

AUTHORS' CONCLUSIONS

This review highlights the major limitations of the available evidence concerning current treatment interventions for fractures of the distal femur. The currently available evidence is incomplete and insufficient to inform clinical practice. Priority should be given to randomised controlled trials comparing contemporary treatments for people with fractures of the distal femur. At a minimum, these should report validated patient-reported functional and quality-of-life outcomes at one and two years, with an agreed core outcome set. All trials should be reported in full using the CONSORT guidelines.

Five-year outcomes for patients sustaining severe fractures of the lower limb : mid-term results from the Wound management for Open Lower Limb Fracture (WOLLF) trial

AIMS

The aim of this study was to report the outcomes of patients with severe open fractures of the lower limb in the five years after they took part in the Wound management for Open Lower Limb Fracture (WOLLF) trial.

METHODS

The WOLLF trial compared standard dressings to negative pressure wound therapy (NPWT) applied at the end of the first surgical wound debridement, and patients were followed-up for 12 months. At 12 months, 170 of the original 460 participants agreed to take part in this medium-term follow-up study. Patients reported their Disability Rating Index (DRI) (0 to 100, where 100 is total disability) and health-related quality of life (HRQoL) using the EuroQol five-dimension three-level health questionnaire (EQ-5D-3L) annually by self-reported questionnaire. Further surgical interventions related to the open fracture were also recorded.

RESULTS

There was no evidence of a difference in patient-reported disability, HRQoL, or the need for further surgery between patients treated with NPWT versus standard dressings at five years. Considering the combined results for all participants, there was a small but statistically significant change in DRI scores over time (1.6 units per year; p = 0.005), but no evidence that EQ-5D-3L scores changed significantly during years two to five (p = 0.551).

CONCLUSION

This study shows that the high levels of disability and reduced HRQoL reported by patients 12 months after severe open fractures of the lower limb persist in the medium term, with little evidence of improvement between years two and five. Cite this article: Bone Joint J 2022;104-B(5):633-639.

Plaster cast versus functional bracing for Achilles tendon rupture: the UKSTAR RCT

BACKGROUND

Achilles tendon rupture affects > 11,000 people each year in the UK, leading to prolonged periods away from work, sports and social activities. Traditionally, the ruptured tendon is held still in a plaster cast for ≥ 8 weeks. Functional bracing is an alternative treatment that allows patients to mobilise earlier, but there is little evidence about how bracing affects patients' recovery.

OBJECTIVES

To measure the Achilles Tendon Rupture Score, quality of life, complications and resource use of patients receiving non-operative treatment for an Achilles tendon rupture treated with plaster cast compared with those treated with functional bracing.

DESIGN

This was a multicentre, randomised, pragmatic, two-group superiority trial.

SETTING

The setting was 39 NHS hospitals.

PARTICIPANTS

A total of 540 adult patients treated non-operatively for Achilles tendon rupture were randomised from July 2016 to May 2018. Exclusion criteria included presenting after 14 days, having had previous rupture and being unable to complete questionnaires.

INTERVENTIONS

A total of 266 participants had a plaster cast applied, with their toes initially pointing to the floor. The cast was changed over 8 weeks to bring the foot into a walking position. A total of 274 patients had a functional brace that facilitated immediate weight-bearing. The foot position was adjusted within the brace over the same 8-week period.

MAIN OUTCOME MEASURES

Achilles Tendon Rupture Score is patient reported and assesses symptoms and physical activity related to the Achilles tendon (score 0-100, with 100 being the best possible outcome). The secondary outcomes were quality of life, complications and resource use at 8 weeks and at 3, 6 and 9 months.

RESULTS

Participants had a mean age of 48.7 years, were predominantly male (79%) and had ruptured their tendon during sports (70%). Over 93% of participants completed follow-up. There was no statistically significant difference in Achilles Tendon Rupture Score at 9 months post injury (-1.38, 95% confidence interval -4.9 to 2.1). There was a statistically significant difference in Achilles Tendon Rupture Score at 8 weeks post injury in favour of the functional brace group (5.53, 95% confidence interval 2.0 to 9.1), but not at 3 or 6 months post injury. Quality of life showed the same pattern, with a statistically significant difference at 8 weeks post injury but not at later time points. Complication profiles were similar in both groups. Re-rupture of the tendon occurred 17 times in the plaster cast group and 13 times in the functional brace group. There was no difference in resource use.

CONCLUSIONS

This trial provides strong evidence that early weight-bearing in a functional brace provides similar outcomes to traditional plaster casting and is safe for patients receiving non-operative treatment of Achilles tendon rupture. The probability that functional bracing is cost-effective exceeds 95% for the base-case imputed analysis, assuming a cost-effectiveness threshold of £20,000 per quality-adjusted life-year. On average, functional brace is associated with lower costs (-£103, 95% confidence interval -£290 to £84) and more quality-adjusted life-years (0.015, 95% confidence interval -0.0013 to 0.030) than plaster cast.

LIMITATIONS

Some patients declined to participate in the trial, but only a small proportion of these declined because they had a preference for one treatment or another. Overall, 58% of eligible patients agreed to participate, so the participants are broadly representative of the population under investigation.

FUTURE WORK

Although the UK Study of Tendo Achilles Rehabilitation provides guidance with regard to early management, rehabilitation following Achilles tendon rupture is prolonged and further research is required to define the optimal mode of rehabilitation after the initial cast/brace has been removed.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN62639639.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 8. See the NIHR Journals Library website for further project information.

Baseline quality of life in people with hip fracture: results from the multicentre WHiTE cohort study

Aims

To assess the variation in pre-fracture quality of life (QoL) within the UK hip fracture population, and quantify the nature and strength of associations between QoL and other routinely collected patient characteristics and treatment choices.

Methods

The World Hip Trauma Evaluation (WHiTE) study, an observational cohort study of UK hip fracture patients, collects a range of routine data and a health-related QoL score (EuroQol five-dimension questionnaire (EQ-5D)). Pre-fracture QoL data are summarized and statistical models fitted to understand associations between QoL, patient characteristics, fracture types, and operations.

Results

Fitting a multiple linear regression model indicated that 36.5% of the variance in pre-fracture EQ-5D scores was explained by routinely collected patient characteristics: sex (0.14%), age (0.17%), American Society of Anesthesiologists (ASA) score (0.73%), Abbreviated Mental Test Score (AMTS; 1.3%), pre-fracture mobility (11.2%), and EQ-5D respondent (participant, relative, or carer; 23.0%). There was considerable variation in pre-fracture EQ-5D scores between operations within fracture types. Participants with trochanteric fractures reported statistically significant but not clinically relevant lower pre-fracture QoL than those with intracapsular fractures. Participants with intracapsular fractures treated with internal fixation or total hip arthroplasty (THA) reported better QoL than those treated with hemiarthroplasty with the overall fittest group receiving THA.

Conclusion

Pre-fracture QoL varies considerably between hip fracture patients; it is generally higher in younger than older patients, patients with better mobility, and those patients who live more independently. Pre-fracture QoL is significantly associated with a range of patient characteristics (e.g. age, mobility, residency). These data explain ~35% of the variation in QoL.

Cite this article: Bone Joint Res 2020;9(8):468–476.

The PAT randomized clinical trial

AIMS

A pragmatic, single-centre, double-blind randomized clinical trial was conducted in a NHS teaching hospital to evaluate whether there is a difference in functional knee scores, quality-of-life outcome assessments, and complications at one-year after intervention between total knee arthroplasty (TKA) and patellofemoral arthroplasty (PFA) in patients with severe isolated patellofemoral arthritis.

METHODS

This parallel, two-arm, superiority trial was powered at 80%, and involved 64 patients with severe isolated patellofemoral arthritis. The primary outcome measure was the functional section of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score at 12 months. Secondary outcomes were the full 24-item WOMAC, Oxford Knee Score (OKS), American Knee Society Score (AKSS), EuroQol five dimension (EQ-5D) quality-of-life score, the University of California, Los Angeles (UCLA) Physical Activity Rating Scale, and complication rates collected at three, six, and 12 months. For longer-term follow-up, OKS, EQ-5D, and self-reported satisfaction score were collected at 24 and 60 months.

RESULTS

Among 64 patients who were randomized, five patients did not receive the allocated intervention, three withdrew, and one declined the intervention. There were no statistically significant differences in the patients' WOMAC function score at 12 months (adjusted mean difference, -1.2 (95% confidence interval -9.19 to 6.80); p = 0.765). There were no clinically significant differences in the secondary outcomes. Complication rates were comparable (superficial surgical site infections, four in the PFA group versus five in the TKA group). There were no statistically significant differences in the patients' OKS score at 24 and 60 months or self-reported satisfaction score or pain-free years.

CONCLUSION

Among patients with severe isolated patellofemoral arthritis, this study found similar functional outcome at 12 months and mid-term in the use of PFA compared with TKA. Cite this article: Bone Joint J 2020;102-B(3):310-318.

Interpreting and reporting fracture classification and operation type in hip fracture

Aims

This study explores data quality in operation type and fracture classification recorded as part of a large research study and a national audit with an independent review.

Patients and Methods

At 17 centres, an expert surgeon reviewed a randomly selected subset of cases from their centre with regard to fracture classification using the AO system and type of operation performed. Agreement for these variables was then compared with the data collected during conduct of the World Hip Trauma Evaluation (WHiTE) cohort study. Both types of surgery and fracture classification were collapsed to identify the level of detail of reporting that achieved meaningful agreement. In the National Hip Fracture Database (NHFD), the types of operation and fracture classification were explored to identify the proportion of “highly improbable” combinations.

Results

The records were reviewed for 903 cases. Agreement for the subtypes of extracapsular fracture was poor; most centres achieved no better than “fair” agreement. When the classification was collapsed to a single option for “extracapsular” fracture, only four centres failed to have at least “moderate” agreement. There was only “moderate” agreement for the subtypes of intracapsular fracture, which improved to “substantial” when collapsed to “intracapsular”. Subtrochanteric fracture types were well reported with “substantial” agreement. There was near “perfect” agreement for internal fixation procedures. “Perfect” or “substantial” agreement was achieved when the type of arthroplasty surgery was reported at the level of “hemiarthroplasty” and “total hip replacement”. When reviewing data submitted to the NHFD, a minimum of 5.2% of cases contained “highly improbable” procedures for the stated fracture classification.

Conclusion

The complexity of collecting fracture classification data at a national scale compromises the accuracy with which detailed classification systems can be reported. Data around type of surgery performed show similar tendencies. Data capture, reporting, and interpretation in future studies must take this into account. Cite this article: Bone Joint J 2019;101-B:1292–1299

Percutaneous fixation with Kirschner wires versus volar locking-plate fixation in adults with dorsally displaced fracture of distal radius: five-year follow-up of a randomized controlled trial

Aims

The aim of this study was to compare the clinical effectiveness of Kirschner wire (K-wire) fixation with locking-plate fixation for patients with a dorsally displaced fracture of the distal radius in the five years after injury.

Patients and Methods

We report the five-year follow-up of a multicentre, two-arm, parallel-group randomized controlled trial. A total of 461 adults with a dorsally displaced fracture of the distal radius within 3 cm of the radiocarpal joint that required surgical fixation were recruited from 18 trauma centres in the United Kingdom. Patients were excluded if the surface of the wrist joint was so badly displaced it required open reduction. In all, 448 patients were randomized to receive either K-wire fixation or locking-plate fixation. In the K-wire group, there were 179 female and 38 male patients with a mean age of 59.1 years (19 to 89). In the locking-plate group, there were 194 female and 37 male patients with a mean age of 58.3 years (20 to 89). The primary outcome measure was the patient-rated wrist evaluation (PRWE). Secondary outcomes were health-related quality of life using the EuroQol five-dimension three-level (EQ-5D-3L) assessment, and further surgery related to the index fracture.

Results

At 12 months, 402/448 participants (90%) recruited into the main study provided PRWE scores. At year two, 294 participants (66%) provided scores; at year five, 198 participants (44%) provided scores. There was no clinically relevant difference in the PRWE at any point during the five-year follow-up; at five years, the PRWE score was 8.3 (12.5) in the wire group and 11.3 (15.6) in the plate group (95% confidence interval -6.99 to 0.99; p = 0.139). Nor was there a clinically relevant difference in health-related quality of life. Only three participants had further surgery in the five years after their injury (one in the wire group and two in the plate group).

Conclusion

This follow-up study continues to show no evidence of a difference in wrist pain, wrist function, or quality of life for patients treated with wires versus locking plates in the five years following a dorsally displaced fracture of the distal radius.

Cite this article: Bone Joint J 2019;101-B:978–983.

Effect of Negative Pressure Wound Therapy vs Standard Wound Management on 12-Month Disability Among Adults With Severe Open Fracture of the Lower Limb: The WOLLF Randomized Clinical Trial

IMPORTANCE

Open fractures of the lower limb occur when a broken bone penetrates the skin. There can be major complications from these fractures, which can be life-changing.

OBJECTIVES

To assess the disability, rate of deep infection, and quality of life in patients with severe open fracture of the lower limb treated with negative pressure wound therapy (NPWT) vs standard wound management after the first surgical debridement of the wound.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter randomized trial performed in the UK Major Trauma Network, recruiting 460 patients aged 16 years or older with a severe open fracture of the lower limb from July 2012 through December 2015. Final outcome data were collected through November 2016. Exclusions were presentation more than 72 hours after injury and inability to complete questionnaires.

INTERVENTIONS

NPWT (n = 226) in which an open-cell solid foam or gauze was placed over the surface of the wound and connected to a suction pump, creating a partial vacuum over the dressing, vs standard dressings not involving application of negative pressure (n = 234).

MAIN OUTCOMES AND MEASURES

Disability Rating Index score (range, 0 [no disability] to 100 [completely disabled]) at 12 months was the primary outcome measure, with a minimal clinically important difference of 8 points. Secondary outcomes were complications including deep infection and quality of life (score ranged from 1 [best possible] to -0.59 [worst possible]; minimal clinically important difference, 0.08) collected at 3, 6, 9, and 12 months.

RESULTS

Among 460 patients who were randomized (mean age, 45.3 years; 74% men), 88% (374/427) of available study participants completed the trial. There were no statistically significant differences in the patients' Disability Rating Index score at 12 months (mean score, 45.5 in the NPWT group vs 42.4 in the standard dressing group; mean difference, -3.9 [95% CI, -8.9 to 1.2]; P = .13), in the number of deep surgical site infections (16 [7.1%] in the NPWT group vs 19 [8.1%] in the standard dressing group; difference, 1.0% [95% CI, -4.2% to 6.3%]; P = .64), or in quality of life between groups (difference in EuroQol 5-dimensions questionnaire, 0.02 [95% CI, -0.05 to 0.08]; Short Form-12 Physical Component Score, 0.5 [95% CI, -3.1 to 4.1] and Mental Health Component Score, -0.4 [95% CI, -2.2 to 1.4]).

CONCLUSIONS AND RELEVANCE

Among patients with severe open fracture of the lower limb, use of NPWT compared with standard wound dressing did not improve self-rated disability at 12 months. The findings do not support this treatment for severe open fractures.

TRIAL REGISTRATION

isrctn.org Identifier: ISRCTN33756652.

Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial

BACKGROUND

Femoroacetabular impingement syndrome is an important cause of hip pain in young adults. It can be treated by arthroscopic hip surgery, including reshaping the hip, or with physiotherapist-led conservative care. We aimed to compare the clinical effectiveness of hip arthroscopy with best conservative care.

METHODS

UK FASHIoN is a pragmatic, multicentre, assessor-blinded randomised controlled trial, done at 23 National Health Service hospitals in the UK. We enrolled patients with femoroacetabular impingement syndrome who presented at these hospitals. Eligible patients were at least 16 years old, had hip pain with radiographic features of cam or pincer morphology but no osteoarthritis, and were believed to be likely to benefit from hip arthroscopy. Patients with bilateral femoroacetabular impingement syndrome were eligible; only the most symptomatic hip was randomly assigned to treatment and followed-up. Participants were randomly allocated (1:1) to receive hip arthroscopy or personalised hip therapy (an individualised, supervised, and progressive physiotherapist-led programme of conservative care). Randomisation was stratified by impingement type and recruiting centre and was done by research staff at each hospital, using a central telephone randomisation service. Patients and treating clinicians were not masked to treatment allocation, but researchers who collected the outcome assessments and analysed the results were masked. The primary outcome was hip-related quality of life, as measured by the patient-reported International Hip Outcome Tool (iHOT-33) 12 months after randomisation, and analysed in all eligible participants who were allocated to treatment (the intention-to-treat population). This trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN64081839, and is closed to recruitment.

FINDINGS

Between July 20, 2012, and July 15, 2016, we identified 648 eligible patients and recruited 348 participants: 171 participants were allocated to receive hip arthroscopy and 177 to receive personalised hip therapy. Three further patients were excluded from the trial after randomisation because they did not meet the eligibility criteria. Follow-up at the primary outcome assessment was 92% (319 of 348 participants). At 12 months after randomisation, mean iHOT-33 scores had improved from 39·2 (SD 20·9) to 58·8 (27·2) for participants in the hip arthroscopy group, and from 35·6 (18·2) to 49·7 (25·5) in the personalised hip therapy group. In the primary analysis, the mean difference in iHOT-33 scores, adjusted for impingement type, sex, baseline iHOT-33 score, and centre, was 6·8 (95% CI 1·7-12·0) in favour of hip arthroscopy (p=0·0093). This estimate of treatment effect exceeded the minimum clinically important difference (6·1 points). There were 147 patient-reported adverse events (in 100 [72%] of 138 patients) in the hip arthroscopy group) versus 102 events (in 88 [60%] of 146 patients) in the personalised hip therapy group, with muscle soreness being the most common of these (58 [42%] vs 69 [47%]). There were seven serious adverse events reported by participating hospitals. Five (83%) of six serious adverse events in the hip arthroscopy group were related to treatment, and the one in the personalised hip therapy group was not. There were no treatment-related deaths, but one patient in the hip arthroscopy group developed a hip joint infection after surgery.

INTERPRETATION

Hip arthroscopy and personalised hip therapy both improved hip-related quality of life for patients with femoroacetabular impingement syndrome. Hip arthroscopy led to a greater improvement than did personalised hip therapy, and this difference was clinically significant. Further follow-up will reveal whether the clinical benefits of hip arthroscopy are maintained and whether it is cost effective in the long term.

FUNDING

The Health Technology Assessment Programme of the National Institute of Health Research.

Intramedullary nail fixation versus locking plate fixation for adults with a fracture of the distal tibia: the UK FixDT RCT

BACKGROUND

The best treatment for fractures of the distal tibia remains controversial. Most of these fractures require surgical fixation, but the outcomes are unpredictable and complications are common.

OBJECTIVES

To assess disability, quality of life, complications and resource use in patients treated with intramedullary (IM) nail fixation versus locking plate fixation in the 12 months following a fracture of the distal tibia.

DESIGN

This was a multicentre randomised trial.

SETTING

The trial was conducted in 28 UK acute trauma centres from April 2013 to final follow-up in February 2017.

PARTICIPANTS

In total, 321 adult patients were recruited. Participants were excluded if they had open fractures, fractures involving the ankle joint, contraindication to nailing or inability to complete questionnaires.

INTERVENTIONS

IM nail fixation (n = 161), in which a metal rod is inserted into the hollow centre of the tibia, versus locking plate fixation (n = 160), in which a plate is attached to the surface of the tibia with fixed-angle screws.

MAIN OUTCOME MEASURES

The primary outcome measure was the Disability Rating Index (DRI) score, which ranges from 0 points (no disability) to 100 points (complete disability), at 6 months with a minimum clinically important difference of 8 points. The DRI score was also collected at 3 and 12 months. The secondary outcomes were the Olerud-Molander Ankle Score (OMAS), quality of life as measured using EuroQol-5 Dimensions (EQ-5D), complications such as infection, and further surgery. Resource use was collected to inform the health economic evaluation.

RESULTS

Participants had a mean age of 45 years (standard deviation 16.2 years), were predominantly male (61%, 197/321) and had experienced traumatic injury after a fall (69%, 223/321). There was no statistically significant difference in DRI score at 6 months [IM nail fixation group, mean 29.8 points, 95% confidence interval (CI) 26.1 to 33.7 points; locking plate group, mean 33.8 points, 95% CI 29.7 to 37.9 points; adjusted difference, 4.0 points, 95% CI -1.0 to 9.0 points; p = 0.11]. There was a statistically significant difference in DRI score at 3 months in favour of IM nail fixation (IM nail fixation group, mean 44.2 points, 95% CI 40.8 to 47.6 points; locking plate group, mean 52.6 points, 95% CI 49.3 to 55.9 points; adjusted difference 8.8 points, 95% CI 4.3 to 13.2 points; p < 0.001), but not at 12 months (IM nail fixation group, mean 23.1 points, 95% CI 18.9 to 27.2 points; locking plate group, 24.0 points, 95% CI 19.7 to 28.3 points; adjusted difference 1.9 points, 95% CI -3.2 to 6.9 points; p = 0.47). Secondary outcomes showed the same pattern, including a statistically significant difference in mean OMAS and EQ-5D scores at 3 and 6 months in favour of IM nail fixation. There were no statistically significant differences in complications, including the number of postoperative infections (13% in the locking plate group and 9% in the IM nail fixation group). Further surgery was more common in the locking plate group (12% in locking plate group and 8% in IM nail fixation group at 12 months). The economic evaluation showed that IM nail fixation provided a slightly higher quality of life in the 12 months after injury and at lower cost and, therefore, it was cost-effective compared with locking plate fixation. The probability of cost-effectiveness for IM nail fixation exceeded 90%, regardless of the value of the cost-effectiveness threshold.

LIMITATIONS

As wound dressings after surgery are clearly visible, it was not possible to blind the patients to their treatment allocation. This evidence does not apply to intra-articular (pilon) fractures of the distal tibia.

CONCLUSIONS

Among adults with an acute fracture of the distal tibia who were randomised to IM nail fixation or locking plate fixation, there were similar disability ratings at 6 months. However, recovery across all outcomes was faster in the IM nail fixation group and costs were lower.

FUTURE WORK

The potential benefit of IM nail fixation in several other fractures requires investigation. Research is also required into the role of adjuvant treatment and different rehabilitation strategies to accelerate recovery following a fracture of the tibia and other long-bone fractures in the lower limb. The patients in this trial will remain in longer-term follow-up.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN99771224 and UKCRN 13761.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 25. See the NIHR Journals Library website for further project information.

A comparison of the cost-effectiveness of intramedullary nail fixation and locking plate fixation in the treatment of adult patients with an extra-articular fracture of the distal tibia: economic evaluation based on the FixDT trial

Aims

The aim of this study was to compare the cost-effectiveness of intramedullary nail fixation and 'locking' plate fixation in the treatment of extra-articular fractures of the distal tibia.

Patients and Methods

An economic evaluation was conducted from the perspective of the United Kingdom National Health Service (NHS) and personal social services (PSS), based on evidence from the Fixation of Distal Tibia Fractures (UK FixDT) multicentre parallel trial. Data from 321 patients were available for analysis. Costs were collected prospectively over the 12-month follow-up period using trial case report forms and participant-completed questionnaires. Cost-effectiveness was reported in terms of incremental cost per quality adjusted life year (QALY) gained, and net monetary benefit. Sensitivity analyses were conducted to test the robustness of cost-effectiveness estimates.

Results

Mean NHS and PSS costs were significantly lower for patients treated with an intramedullary nail than for those treated with a locking plate (-£970, 95% confidence interval (CI) -1685 to -256; p = 0.05). There was a small increase in QALYs gained in the nail fixation group (0.01, 95% CI -0.03 to 0.06; p = 0.52). The probability of cost-effectiveness for nail fixation exceeded 90% at cost-effectiveness thresholds as low as £15 000 per additional QALY. The cost-effectiveness results remained robust to several sensitivity analyses.

Conclusion

This trial-based economic evaluation suggests that nail fixation is a cost-effective alternative to locking plate fixation. Cite this article: Bone Joint J 2018;100-B:624-33.

Unit of analysis issues in laboratory-based research

Many studies in the biomedical research literature report analyses that fail to recognise important data dependencies from multilevel or complex experimental designs. Statistical inferences resulting from such analyses are unlikely to be valid and are often potentially highly misleading. Failure to recognise this as a problem is often referred to in the statistical literature as a unit of analysis (UoA) issue. Here, by analysing two example datasets in a simulation study, we demonstrate the impact of UoA issues on study efficiency and estimation bias, and highlight where errors in analysis can occur. We also provide code (written in R) as a resource to help researchers undertake their own statistical analyses.

Effect of Locking Plate Fixation vs Intramedullary Nail Fixation on 6-Month Disability Among Adults With Displaced Fracture of the Distal Tibia: The UK FixDT Randomized Clinical Trial

IMPORTANCE

The best treatment for fractures of the distal tibia remains controversial. Most such fractures require surgical fixation but outcomes are unpredictable and complications are common.

OBJECTIVE

To assess disability, quality of life, and complications in patients with displaced tibial fracture treated with intramedullary nail fixation vs locking plate fixation.

DESIGN, SETTING, AND PARTICIPANTS

A multicenter randomized trial recruiting 321 patients 16 years or older with an acute, displaced, extra-articular fracture of the distal tibia from April 2013 through April 2016 with final follow-up in February 2017. Exclusion criteria included open fractures, fractures involving the ankle joint, contraindication to nailing, or inability to complete questionnaires.

INTERVENTIONS

Intramedullary nail fixation (nail group; n = 161), a metal rod inserted into the hollow center of the tibia, vs locking plate fixation (plate group; n = 160), a plate attached to the surface of the tibia with fixed-angle screws.

MAIN OUTCOMES AND MEASURES

Disability Rating Index (DRI; score range, 0 [no disability] to 100 [complete disability]) at 6 months was the primary outcome measure, with a minimal clinically important difference of 8 points. DRI measurement was also collected at 3 and 12 months. Secondary outcomes were the Olerud-Molander Ankle Score (OMAS), quality of life, and complications (such as infection and further surgery).

RESULTS

Among 321 randomized patients (mean age, 45 years [SD, 16.2]; men, 197 [61%]; had experienced traumatic injury after a fall, 223 [69%]), 258 completed the study. There was no statistically significant difference in the DRI score at 6 months between groups (mean score, 29.8 in the nail group vs 33.8 in the plate group; adjusted difference, 4.0 [95% CI, -1.0 to 9.0], P = .11). There was a statistically significant difference in the DRI score at 3 months in favor of nail fixation (mean score, 44.2 in the nail group and 52.6 in the plate group; adjusted difference, 8.8 [95% CI, 4.3 to 13.2], P < .001), but not at 12 months (mean score, 23.1 in the nail group and 24.0 in the plate group; adjusted difference, 1.9 [95% CI, -3.2 to 6.9], P = .47). Secondary outcomes showed the same pattern, including a statistically significant difference in mean OMAS at 3 and 6 months in favor of nail fixation. There were no statistically significant differences in complications, including the number of postoperative infections (9% in the nail group vs 13% in the plate group). Further surgery was more common in the plate group at 12 months (8% in nail group vs 12% in plate group).

CONCLUSIONS AND RELEVANCE

Among patients 16 years or older with an acute, displaced, extra-articular fracture of the distal tibia, neither nail fixation nor locking plate fixation resulted in superior disability status at 6 months. Other factors may need to be considered in deciding the optimal approach.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: ISRCTN99771224.

Cast versus functional brace in the rehabilitation of patients treated non-operatively for a rupture of the Achilles tendon: protocol for the UK study of tendo achilles rehabilitation (UK STAR) multi-centre randomised trial

INTRODUCTION

Achilles tendon rupture affects over 11 000 people yearly in the UK, and the incidence is increasing. Controversy remains with regard to the best rehabilitation strategy for these patients. In operatively treated patients, functional bracing provides better outcomes compared with plaster casts. However, the role of functional bracing in non-operatively managed patients is unclear. This is the protocol for a multicentre randomised trial of plaster cast immobilisation versus functional bracing for patients with a non-operatively managed Achilles tendon rupture.

METHODS AND ANALYSIS

All adults presenting with a primary rupture of the Achilles tendon will be screened. Non-operatively treated patients will be eligible to take part in the trial. Broad eligibility criteria will ensure that the results of the study can be generalised to the wider patient population. Randomisation will be on a 1:1 basis. Both rehabilitation strategies are widely used within the National Health Service. Standardised protocols will be followed, and details of plaster material and brace will be as per the site's usual practice.A minimum of 330 patients will be randomised to obtain 90% power to detect a difference of 8 points in Achilles Tendon Total Rupture Score at 9 months. Quality of life and resource use will be collected at 3, 6 and 9 months. The differences between treatment groups will be assessed on an intention-to-treat basis. The results of the trial-based economic evaluation will be expressed in terms of incremental cost per quality-adjusted life-year gained.

ETHICS AND DISSEMINATION

The National Research Ethic Committee approved this study on 18 March 2016 (16/SC/0109).The National Institute for Health Research Health Technology Assessment monograph and a manuscript to a peer-reviewed journal will be submitted on completion of the trial (summer 2019). The results of this trial will substantially inform clinical practice on the clinical and cost-effectiveness of the treatment of this injury. This study has been registered on the International Standard Randomised Controlled Trial Number registry with reference no ISRCTN62639639.

A pragmatic randomised controlled trial comparing the efficacy of a femoral nerve block and periarticular infiltration for early pain relief following total knee arthroplasty

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).

PATIENTS AND METHODS

A pragmatic, single centre, two arm parallel group, patient blinded, randomised controlled trial was undertaken. All patients due for TKA were eligible. Exclusion criteria included contraindications to the medications involved in the study and patients with a neurological abnormality of the lower limb. Patients received either a femoral nerve block with 75 mg of 0.25% levobupivacaine hydrochloride around the nerve, or periarticular infiltration with 150 mg of 0.25% levobupivacaine hydrochloride, 10 mg morphine sulphate, 30 mg ketorolac trometamol and 0.25 mg of adrenaline all diluted with 0.9% saline to make a volume of 150 ml.

RESULTS

A total of 264 patients were recruited and data from 230 (88%) were available for the primary analysis. Intention-to-treat analysis of the primary outcome measure of a visual analogue score for pain on the first post-operative day, prior to physiotherapy, was similar in both groups. The mean difference was -0.7 (95% confidence interval (CI) -5.9 to 4.5; p = 0.834). The periarticular group used less morphine in the first post-operative day compared with the femoral nerve block group (74%, 95% CI 55 to 99). The femoral nerve block group reported 39 adverse events, of which 27 were serious, in 31 patients and the periarticular group reported 51 adverse events, of which 38 were serious, in 42 patients up to six weeks post-operatively. None of the adverse events were directly attributed to either of the interventions under investigation.

CONCLUSION

Periarticular infiltration is a viable and safe alternative to femoral nerve block for the early post-operative relief of pain following TKA. Cite this article: Bone Joint J 2017;99-B:904-11.

Do radiological and functional outcomes correlate for fractures of the distal radius?

AIMS

We conducted a study to determine whether radiological parameters correlate with patient reported functional outcome, health-related quality of life and physical measures of function in patients with a fracture of the distal radius.

PATIENTS AND METHODS

The post-operative palmar tilt and ulnar variance at six weeks and 12 months were correlated with the Patient Rated Wrist Evaluation, Disabilities of the Arm, Shoulder and Hand, and EuroQol scores, grip strength, pinch strength and range of movement at three, six and 12 months for 50 patients (mean age 57 years; 26 to 85) having surgical fixation, with either percutaneous pinning or reconstruction with a volar plate, for a fracture of the distal radius.

RESULTS

Radiological parameters were found to correlate poorly with the patient reported outcomes (r = 0.00 to 0.47) and physical measures of function (r = 0.01 to 0.51) at all intervals.

CONCLUSION

This study raises concerns about the use of radiological parameters to determine management, and to act as a surrogates for successful treatment, in patients with a fracture of the distal radius. Restoration of 'normal' radiographic parameters may not be necessary to achieve a satisfactory functional outcome for the patient. Cite this article: Bone Joint J 2017;99-B:376-82.

The use of high-dose dual-impregnated antibiotic-laden cement with hemiarthroplasty for the treatment of a fracture of the hip: The Fractured Hip Infection trial

Aims

A fracture of the hip is the most common serious orthopaedic injury, and surgical site infection (SSI) is one of the most significant complications, resulting in increased mortality, prolonged hospital stay and often the need for further surgery. Our aim was to determine whether high dose dual antibiotic impregnated bone cement decreases the rate of infection.

Patients and Methods

A quasi-randomised study of 848 patients with an intracapsular fracture of the hip was conducted in one large teaching hospital on two sites. All were treated with a hemiarthroplasty. A total of 448 patients received low dose single-antibiotic impregnated cement (control group) and 400 patients received high dose dual-antibiotic impregnated cement (intervention group). The primary outcome measure was deep SSI at one year after surgery.

Results

The rate of deep SSI was 3.5% in the control group and 1.1% in the intervention group (p = 0.041; logistic regression adjusting for age and gender). The overall rate of non-infective surgical complications did not differ between the two groups (unadjusted chi-squared test; p > 0.999).

Conclusion

The use of high dose dual-antibiotic impregnated cement in these patients significantly reduces the rate of SSI compared with standard low dose single antibiotic loaded bone cement.

Cite this article: Bone Joint J 2016;98-B:1534–1541.

Cost effectiveness of treatment with percutaneous Kirschner wires versus volar locking plate for adult patients with a dorsally displaced fracture of the distal radius: analysis from the DRAFFT trial

We present an economic evaluation using data from the Distal Radius Acute Fracture Fixation Trial (DRAFFT) to compare the relative cost effectiveness of percutaneous Kirschner wire (K-wire) fixation and volar locking-plate fixation for patients with dorsally-displaced fractures of the distal radius. The cost effectiveness analysis (cost per quality-adjusted life year; QALY) was derived from a multi-centre, two-arm, parallel group, assessor-blind, randomised controlled trial which took place in 18 trauma centres in the United Kingdom. Data from 460 patients were available for analysis, which includes both a National Health Service cost perspective including costs of surgery, implants and healthcare resource use over a 12-month period after surgery, and a societal perspective, which includes the cost of time off work and the need for additional private care. There was only a small difference in QALYs gained for patients treated with locking-plate fixation over those treated with K-wires. At a mean additional cost of £714 (95% confidence interval 588 to 865) per patient, locking-plate fixation presented an incremental cost effectiveness ratio (ICER) of £89,322 per QALY within the first 12 months of treatment. Sensitivity analyses were undertaken to assess the ICER of locking-plate fixation compared with K-wires. These were greater than £30,000. Compared with locking-plate fixation, K-wire fixation is a 'cost saving' intervention, with similar health benefits.

Protocol for a randomised controlled trial of standard wound management versus negative pressure wound therapy in the treatment of adult patients with an open fracture of the lower limb: UK Wound management of Lower Limb Fractures (UK WOLLF)

INTRODUCTION

Patients who sustain open lower limb fractures have reported infection risks as high as 27%. The type of dressing applied after initial debridement could potentially affect this risk. In this trial, standard dressings will be compared with a new emerging treatment, negative pressure wound therapy, for patients with open lower limb fractures.

METHODS AND ANALYSIS

All adult patients presenting with an open lower limb fracture, with a Gustilo and Anderson (G&A) grade 2/3, will be considered for inclusion. 460 consented patients will provide 90% power to detect a difference of eight points in the Disability Rating Index (DRI) score at 12 months, at the 5% level. A randomisation sequence, stratified by trial centre and G&A grade, will be produced and administered by a secure web-based service. A qualitative substudy will assess patients' experience of giving consent for the trial, and acceptability of trial procedures to patients and staff. Patients will have clinical follow-up in a fracture clinic up to a minimum of 12 months as per standard National Health Service (NHS) practice. Functional and quality of life outcome data will be collected using the DRI, SF12 and EQ-5D questionnaires at 3, 6, 9 and 12 months postoperatively. In addition, information will be requested with regards to resource use and any late complications or surgical interventions related to their injury. The main analysis will investigate differences in the DRI score at 1 year after injury, between the two treatment groups on an intention-to-treat basis. Tests will be two sided and considered to provide evidence for a significant difference if p values are less than 0.05.

ETHICS AND DISSEMINATION

Ethical approval was given by NRES Committee West Midlands-Coventry & Warwickshire on 6/2/2012 (ref: 12/WM/0001). The results of the trial will be disseminated via peer-reviewed publications and presentations at relevant conferences.

TRIAL REGISTRATION NUMBER

ISRCTN33756652.

Is it time to revisit the AO classification of fractures of the distal radius? Inter- and intra-observer reliability of the AO classification

We conducted an observational radiographic study to determine the inter- and intra-observer reliability of the AO classification of fractures of the distal radius. Plain posteroanterior and lateral radiographs of 456 patients with an acute fracture of the distal radius were classified by a consultant orthopaedic hand specialist and two specialist trainees, and the k coefficient for the inter- and intra-observer reliability of the type, group and subgroup classification was calculated. Only the type of fracture (A, B or C) was found to provide substantial intra-observer reliability (k type 0.65). The inclusion of 'group' and 'subgroup' into the classification reduced the inter-observer reliability to fair (kgroup 0.29, ksubgroup = 0.28) and the intra-observer reliability to moderate (kgroup 0.53, ksubgroup 0.49). Disagreement was found to arise between specific subgroups, which may be amenable to clarification.

UK DRAFFT: a randomised controlled trial of percutaneous fixation with Kirschner wires versus volar locking-plate fixation in the treatment of adult patients with a dorsally displaced fracture of the distal radius

BACKGROUND

In high-income countries, 6% of all women will have sustained a fracture of the wrist (distal radius) by the age of 80 years and 9% by the age of 90 years. Advances in orthopaedic surgery have improved the outcome for patients: many such fractures can be treated in a plaster cast alone, but others require surgical fixation to hold the bone in place while they heal. The existing evidence suggests that modern locking-plate fixation provides improved functional outcomes, but costs more than traditional wire fixation.

METHODS

In this multicentre trial, we randomly assigned 461 adult patients having surgery for an acute dorsally displaced fracture of the distal radius to either percutaneous Kirschner-wire fixation or locking-plate fixation. The primary outcome measure was the Patient-Rated Wrist Evaluation© (PRWE) questionnaire at 12 months after the fracture. In this surgical trial, neither the patients nor the surgeons could be blind to the intervention. We also collected information on complications and combined costs and quality-adjusted life-years (QALYs) to assess cost-effectiveness.

RESULTS

The baseline characteristics of the two groups were well balanced and over 90% of patients completed follow-up. Both groups of patients recovered wrist function by 12 months. There was no clinically relevant difference in the PRWE questionnaire score at 3 months, 6 months or 12 months [difference at 12 months: -1.3; 95% confidence interval (CI) -4.5 to 1.8; p=0.398]. There was no difference in the number of complications in each group and small differences in QALY gains (0.008; 95% CI -0.001 to 0.018); Kirschner-wire fixation represents a cost-saving intervention (-£727; 95% CI -£588 to -£865), particularly in younger patients.

CONCLUSIONS

Contrary to the existing literature, and against the increasing use of locking-plate fixation, this trial shows that there is no difference between Kirschner wires and volar locking plates for patients with dorsally displaced fractures of the distal radius. A Kirschner-wire fixation is less expensive and quicker to perform.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN31379280.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 19, No. 17. See the NIHR Journals Library website for further project information.

Percutaneous fixation with Kirschner wires versus volar locking plate fixation in adults with dorsally displaced fracture of distal radius: randomised controlled trial

OBJECTIVES

To compare the clinical effectiveness of Kirschner wire fixation with locking plate fixation for patients with a dorsally displaced fracture of the distal radius.

DESIGN

A multicentre two arm parallel group assessor blind randomised controlled trial with 1:1 treatment allocation.

SETTING

18 trauma centres in the United Kingdom.

PARTICIPANTS

461 adults with a dorsally displaced fracture of the distal radius within 3 cm of the radiocarpal joint that required surgical fixation. Patients were excluded if the surgeon thought that the surface of the wrist joint was so badly displaced it required open reduction.

INTERVENTIONS

Kirschner wire fixation: wires are passed through the skin over the dorsal aspect of the distal radius and into the bone to hold the fracture in the correct anatomical position. Locking plate fixation: a locking plate is applied through an incision over the volar (palm) aspect of the wrist and secured to the bone with fixed angle locking screws.

PRIMARY OUTCOME MEASURE

validated patient rated wrist evaluation (PRWE). This rates wrist function in two (equally weighted) sections concerning the patient's experience of pain and disability to give a score out of 100.

SECONDARY OUTCOMES

disabilities of arm, shoulder, and hand (DASH) score, the EuroQol (EQ-5D), and complications related to the surgery.

RESULTS

The baseline characteristics of the two groups were well balanced, and over 90% of patients completed follow-up. The wrist function of both groups of patients improved by 12 months. There was no clinically relevant difference in the patient rated wrist score at three, six, or 12 months (difference in favour of the plate group was -1.3, 95% confidence interval -4.5 to 1.8; P=0.40). Nor was there a clinically relevant difference in health related quality of life or the number of complications in each group.

CONCLUSIONS

Contrary to the existing literature, and against the rapidly increasing use of locking plate fixation, this trial found no difference in functional outcome in patients with dorsally displaced fractures of the distal radius treated with Kirschner wires or volar locking plates. Kirschner wire fixation, however, is cheaper and quicker to perform.

TRIAL REGISTRATION

Current Controlled Trials ISCRTN 31379280. UKCRN 8956.

Effect of regional trauma centralization on volume, injury severity and outcomes of injured patients admitted to trauma centres

BACKGROUND

Centralization of complex healthcare services into specialist high-volume centres is believed to improve outcomes. For injured patients, few studies have evaluated the centralization of major trauma services. The aim of this study was to evaluate how a regional trauma network affected trends in admissions, case mix, and outcomes of injured patients.

METHODS

A retrospective before-after study was undertaken of severely injured patients attending four hospitals that became major trauma centres (MTCs) in March 2012. Consecutive patients with major trauma were identified from a national registry and divided into two groups according to injury before or after the launch of a new trauma network. The two cohorts were compared for differences in case mix, demand on hospital resources, and outcomes.

RESULTS

Patient volume increased from 442 to 1326 (200 per cent), operations from 349 to 1231 (253 per cent), critical care bed-days from 1100 to 3704 (237 per cent), and total hospital bed-days from 7910 to 22,772 (188 per cent). Patient age increased on MTC designation from 45.0  years before March 2012 to 48.2 years afterwards (P = 0.021), as did the proportion of penetrating injuries (1.8 versus 4.1 per cent; P = 0.025). Injury severity fell as measured by median Injury Severity Score (16 versus 14) and Revised Trauma Score (4.1 versus 7.8). Fewer patients required secondary transfer to a MTC from peripheral hospitals (19.9 versus 16.1 per cent; P = 0.100). There were no significant differences in total duration of hospital stay, critical care requirements or mortality. However, there was a significant increase, from 55.5 to 62.3 per cent (P < 0.001), in the proportion of patients coded as having a 'good recovery' at discharge after institution of the trauma network.

CONCLUSION

MTC designation leads to an increased case volume with considerable implications for operating theatre capacity and bed occupancy. Although no mortality benefit was demonstrated within 6 months of establishing this trauma network, early detectable advantages included improved functional outcome at discharge.

Proportional-odds models for repeated composite and long ordinal outcome scales

In many medical studies, researchers widely use composite or long ordinal scores, that is, scores that have a large number of categories and a natural ordering often resulting from the sum of a number of short ordinal scores, to assess function or quality of life. Typically, we analyse these using unjustified assumptions of normality for the outcome measure, which are unlikely to be even approximately true. Scores of this type are better analysed using methods reserved for more conventional (short) ordinal scores, such as the proportional-odds model. We can avoid the need for a large number of cut-point parameters that define the divisions between the score categories for long ordinal scores in the proportional-odds model by the inclusion of orthogonal polynomial contrasts. We introduce the repeated measures proportional-odds logistic regression model and describe for long ordinal outcomes modifications to the generalized estimating equation methodology used for parameter estimation. We introduce data from a trial assessing two surgical interventions, briefly describe and re-analyse these using the new model and compare inferences from the new analysis with previously published results for the primary outcome measure (hip function at 12 months postoperatively). We use a simulation study to illustrate how this model also has more general application for conventional short ordinal scores, to select amongst competing models of varying complexity for the cut-point parameters.

An evaluation of the quality of statistical design and analysis of published medical research: results from a systematic survey of general orthopaedic journals

BACKGROUND

The application of statistics in reported research in trauma and orthopaedic surgery has become ever more important and complex. Despite the extensive use of statistical analysis, it is still a subject which is often not conceptually well understood, resulting in clear methodological flaws and inadequate reporting in many papers.

METHODS

A detailed statistical survey sampled 100 representative orthopaedic papers using a validated questionnaire that assessed the quality of the trial design and statistical analysis methods.

RESULTS

The survey found evidence of failings in study design, statistical methodology and presentation of the results. Overall, in 17% (95% confidence interval; 10-26%) of the studies investigated the conclusions were not clearly justified by the results, in 39% (30-49%) of studies a different analysis should have been undertaken and in 17% (10-26%) a different analysis could have made a difference to the overall conclusions.

CONCLUSION

It is only by an improved dialogue between statistician, clinician, reviewer and journal editor that the failings in design methodology and analysis highlighted by this survey can be addressed.

A systematic survey of the quality of research reporting in general orthopaedic journals

The poor reporting and use of statistical methods in orthopaedic papers has been widely discussed by both clinicians and statisticians. A detailed review of research published in general orthopaedic journals was undertaken to assess the quality of experimental design, statistical analysis and reporting. A representative sample of 100 papers was assessed for compliance to CONSORT and STROBE guidelines and the quality of the statistical reporting was assessed using a validated questionnaire. Overall compliance with CONSORT and STROBE guidelines in our study was 59% and 58% respectively, with very few papers fulfilling all criteria. In 37% of papers patient numbers were inadequately reported; 20% of papers introduced new statistical methods in the 'results' section not previously reported in the 'methods' section, and 23% of papers reported no measurement of error with the main outcome measure. Taken together, these issues indicate a general lack of statistical rigour and are consistent with similar reviews undertaken in a number of other scientific and clinical research disciplines. It is imperative that the orthopaedic research community strives to improve the quality of reporting; a failure to do so could seriously limit the development of future research.

UK DRAFFT - a randomised controlled trial of percutaneous fixation with kirschner wires versus volar locking-plate fixation in the treatment of adult patients with a dorsally displaced fracture of the distal radius

Background

Fractures of the distal radius are extremely common injuries in adults. However, the optimal management remains controversial. In general, fractures of the distal radius are treated non-operatively if the bone fragments can be held in anatomical alignment by a plaster cast or orthotic. However, if this is not possible, then operative fixation is required. There are several operative options but the two most common in the UK, are Kirschner-wire fixation (K-wires) and volar plate fixation using fixed-angle screws (locking-plates). The primary aim of this trial is to determine if there is a difference in the Patient-Reported Wrist Evaluation one year following K-wire fixation versus locking-plate fixation for adult patients with a dorsally-displaced fracture of the distal radius.

Methods/design

All adult patients with an acute, dorsally-displaced fracture of the distal radius, requiring operative fixation are potentially eligible to take part in this study. A total of 390 consenting patients will be randomly allocated to either K-wire fixation or locking-plate fixation. The surgery will be performed in trauma units across the UK using the preferred technique of the treating surgeon. Data regarding wrist function, quality of life, complications and costs will be collected at six weeks and three, six and twelve months following the injury. The primary outcome measure will be wrist function with a parallel economic analysis.

Discussion

This pragmatic, multi-centre trial is due to deliver results in December 2013.

Trial registration

Current Controlled Trials ISRCTN31379280

UKCRN portfolio ID 8956

A comparison of Harris and Oxford hip scores for assessing outcome after resurfacing arthroplasty of the hip: can the patient tell us everything we need to know

We have compared the Harris hip score with the Oxford hip score in a population of 358 patients (213 men and 145 women) aged between 19 to 74 years (median 55 years), after resurfacing arthroplasty of the hip (between September 1995 and October 2006) with a median follow-up of 6 years. The Oxford hip score was related to the age of the patient (Mann-Whitney test; p = 0.015), the hip lifetime (p = 0.030) and body mass index (p < 0.001). Correlation analysis indicated a good correlation between overall Harris and Oxford hip scores (Spearman's rank correlation = -0.70; p < 0.001). An analysis of correlations between individual items in the Oxford score and functional domains of the Harris score showed that the range of movement domain of the latter score was correlated with two items from the former score (-0.40 and -0.38; p < 0.001 and p < 0.001). Based on the correlation analysis, this study provides good evidence that the Oxford score can be substituted for the Harris score for long-term assessment of hip function, without significant loss of information.

The comprehensive cohort model in a pilot trial in orthopaedic trauma

BACKGROUND

The primary aim of this study was to provide an estimate of effect size for the functional outcome of operative versus non-operative treatment for patients with an acute rupture of the Achilles tendon using accelerated rehabilitation for both groups of patients. The secondary aim was to assess the use of a comprehensive cohort research design (i.e. a parallel patient-preference group alongside a randomised group) in improving the accuracy of this estimate within an orthopaedic trauma setting.

METHODS

Pragmatic randomised controlled trial and comprehensive cohort study within a level 1 trauma centre. Twenty randomised participants (10 operative and 10 non-operative) and 29 preference participants (3 operative and 26 non-operative). The ge range was 22-72 years and 37 of the 52 patients were men. All participants had an acute rupture of their Achilles tendon and no other injuries. All of the patients in the operative group had a simple end-to-end repair of the tendon with no augmentation. Both groups then followed the same eight-week immediate weight-bearing rehabilitation programme using an off-the-shelf orthotic. The disability rating index (DRI; primary outcome), EQ-5D, Achilles Total Rupture Score and complications were assessed ed at two weeks, six weeks, three months, six months and nine months after initial injury.

RESULTS

At nine months, there was no significant difference in DRI between patients randomised to operative or non-operative management. There was no difference in DRI between the randomised group and the parallel patient preference group. The use of a comprehensive cohort of patients did not provide useful additional information as to the treatment effect size because the majority of patients chose non-operative management.

CONCLUSIONS

Recruitment to clinical trials that compare operative and non-operative interventions is notoriously difficult; especially within the trauma setting. Including a parallel patient preference group to create a comprehensive cohort of patients has been suggested as a way of increasing the power of such trials. In our study, the comprehensive cohort model doubled the number of patients involved in the study. However, a strong preference for non-operative treatment meant that the increased number of patients did not significantly increase the ability of the trial to detect a difference between the two interventions.

TRIAL REGISTRATION

ISRCTN: ISRCTN29053307.

A randomised controlled trial of total hip arthroplasty versus resurfacing arthroplasty in the treatment of young patients with arthritis of the hip joint

Background

Hip replacement (arthroplasty) surgery is a highly successful treatment for patients with severe symptomatic arthritis of the hip joint. For older patients, several designs of Total Hip Arthroplasty have shown excellent results in terms of both function and value for money. However, in younger more active patients, there is approximately a 50% failure rate at 25 years for traditional implants. Hip resurfacing is a relatively new arthroplasty technique. In a recent review of the literature on resurfacing arthroplasty it was concluded that the short-term functional results appear promising but some potential early disadvantages were identified, including the risk of femoral neck fracture and collapse of the head of the femur. The aim of the current study is to assess whether there is a difference in functional hip scores at one year post-operation between Total Hip Arthroplasty and Resurfacing Arthroplasty. Secondary aims include assessment of complication rates for both procedures as well cost effectiveness.

Methods/design

All patients medically fit for surgery and deemed suitable for a resurfacing arthroplasty are eligible to take part in this study. A randomisation sequence will be produced and administered independently. After consenting, all patients will be clinically reviewed and hip function, quality of life and physical activity level will be assessed through questionnaires. The allocated surgery will then be performed with the preferred technique of the surgeon. Six weeks post-operation hip function will be assessed and complications recorded. Three, six and 12 months post-operation hip function, quality of life and physical activity level will be assessed. Additional information about patients' out-of-pocket expenses will also be collected.

Trial registration

Current Controlled Trials ISRCTN33354155

UKCLRN portfolio ID 4093

Serial lung function variability using four portable logging meters

OBJECTIVE

Portable lung function logging meters that allow measurement of peak expiratory flow (PEF) and forced expiratory volume in 1 second (FEV(1)) are useful for the diagnosis and exclusion of asthma. The aim of this study was to investigate the within and between-session variability of PEF and FEV(1) for four logging meters and to determine the sensitivity of meters to detect FEV(1) and PEF diurnal changes.

METHODS

Thirteen assessors (all hospital staff members) were asked to record 1 week of 2-hour PEF and FEV(1) measurements using four portable lung function meters. Within-session variability of PEF and FEV(1) were compared for each meter using a coefficient of variation (COV). Between-session variability was quantified using parameter estimates from a cosinor analysis which modeled diurnal change for both lung function measures and also allowed for variation between days for individual sessions.

RESULTS

The mean within-session COV for FEV(1) was consistently lower than that for PEF (p < 0.001). PEF showed a higher but not significantly different (p = 0.068) sensitivity for detecting diurnal variation than FEV(1). PEF was also slightly more variable between days, but not significantly different than FEV(1) (p = 0.409). PEF and FEV(1) diurnal variability did not differ between the 4 meters (p = 0.154 and 0.882 respectively), but within-session FEV(1) COV differed between meters (p = 0.009).

CONCLUSION

PEF was marginally more sensitive to within-day variability than FEV(1) but was less repeatable. Overall, differences between the 4 meters were small, suggesting that all meters are clinically useful.

Differences in microbial activity and microbial populations of peat associated with suppression of damping-off disease caused by Pythium sylvaticum

The microbiological characteristics associated with disease-suppressive peats are unclear. We used a bioassay for Pythium sylvaticum-induced damping-off of cress seedlings to identify conducive and suppressive peats. Microbial activity in unconditioned peats was negatively correlated with the counts of P. sylvaticum at the end of the bioassay. Denaturing gradient gel electrophoresis (DGGE) profiling and clone library analyses of small-subunit rRNA gene sequences from two suppressive and two conducive peats differed in the bacterial profiles generated and the diversity of sequence populations. There were also significant differences between bacterial sequence populations from suppressive and conducive peats. The frequencies of a number of microbial groups, including the Rhizobium-Agrobacterium group (specifically sequences similar to those for the genera Ochrobactrum and Zoogloea) and the Acidobacteria, increased specifically in the suppressive peats, although no single bacterial group was associated with disease suppression. Fungal DGGE profiles varied little over the course of the bioassay; however, two bands associated specifically with suppressive samples were detected. Sequences from these bands corresponded to Basidiomycete yeast genera. Although the DGGE profiles were similar, fungal sequence diversity also increased during the bioassay. Sequences highly similar to those of Cryptococcus increased in relative abundance during the bioassay, particularly in the suppressive samples. This study highlights the importance of using complementary approaches to molecular profiling of complex populations and provides the first report that basidiomycetous yeasts may be associated with the suppression of Pythium-induced diseases in peats.

Microbial community responses associated with the development of oomycete plant pathogens on tomato roots in soilless growing systems

AIMS

To determine the spread of different oomycete pathogens in hydroponic, soilless tomato growing systems and their impact on established microbial communities, as baseline studies prior to future introduction of microbial inoculants for disease suppression.

METHODS AND RESULTS

The oomycete pathogens, Pythium group F, Pythium aphanidermatum and Phytophthora cryptogea, were introduced into small-scale recirculating tomato growing systems containing rockwool 6 weeks after set-up when roots were well-established. Two weeks later, half of the systems were switched over to run-to-waste. Pythium aphanidermatum spreads the fastest, Pythium group F the slowest and Ph. cryptogea was intermediate in its spread. The switch to run-to-waste had no effect on pathogen recovery. Microbial communities, monitored by dilution plating, were well-established at the first sampling, 6 weeks after set-up and although differences in community levels were found between experiments, changes during any one experiment were small, generally less than 1 log10 CFU g(-1) for bacteria. Pathogen introduction increased microbial community levels in roots but the switch to run-to-waste had no effect. Analysis of bacterial communities through amplification of a fragment of the 16S rRNA gene and DGGE profiling showed that different communities were established within each pathogen experiment and that different communities were established on roots, rockwool and in nutrient solutions. However, no significant changes in microbial profiles were found over time in any experiment.

CONCLUSIONS

In these systems, the microbial communities were well-established 6 weeks after set-up and were resistant to biological and physical perturbation.

SIGNIFICANCE AND IMPACT OF THE STUDY

The implication for microbial inoculation of such systems for disease suppression is that the micro-organisms would either have to be introduced very early during the set-up of the system or be able to replace an established but variable community.

Estimation and projection of population lung cancer trends (United Kingdom)

OBJECTIVE

Reduction of overall cancer mortality in the UK will require a marked decrease in lung cancer incidence and mortality. A method was sought to predict future lung cancer trends at regional and subregional levels to improve planning, aid the monitoring of health promotion strategies, and to assess health gains that might be achieved.

METHODS

Data on 55,000 lung cancer patients were used in an age-cohort model of lung cancer incidence (1981-95) and a parametric model of survival (1981-91). Indicators of deprivation were included in the models. Prevalence was estimated from the product of incidence and survival. Lung cancer trends were predicted to 2015, both at steady state and with an incidence perturbation.

RESULTS

Female lung cancer is predicted to increase, until by 2015 the numbers will almost equal those in men. Cohort coefficients reveal an increasing risk of lung cancer in females born after 1941. Changing these female cohort coefficients to equate to a declining risk after 1941 suggests that, by 2015, around 200 cases per year might be prevented. This would necessitate a marked change in smoking behavior. Survival from lung cancer was significantly associated with social deprivation and health authority of residence.

CONCLUSIONS

A credible model has been derived which can be used for health service and outcome monitoring. The model results have highlighted a priority area for smoking intervention which currently seems to attract little attention.