Most published randomised controlled trials which compare the rates of wear of conventional and cross-linked (XL) polyethylene (PE) in total hip arthroplasty (THA) have described their use with a cementless acetabular component.

We conducted a prospective randomised study to assess the rates of penetration of two distinct types of PE in otherwise identical cemented all-PE acetabular components.

A total of 100 consecutive patients for THA were randomised to receive an acetabular component which had been either highly XL then remelted or moderately XL then annealed.

After a minimum of eight years follow-up, 38 hips in the XL group and 30 hips in the annealed group had complete data (mean follow-up of 9.1 years (7.6 to 10.7) and 8.7 years (7.2 to 10.2), respectively). In the XL group, the steady state rate of penetration from one year onwards was -0.0002 mm/year (sd 0.108): in the annealed group it was 0.1382 mm/year (sd 0.129) (Mann–Whitney U test, p < 0.001). No complication specific to either material was recorded.

These results show that the yearly linear rate of femoral head penetration can be significantly reduced by using a highly XLPE cemented acetabular component.

Cite this article: Bone Joint J 2015;97-B:1458–62.

Background

Approximately half of all hip fractures are displaced intracapsular fractures. The standard treatment for these fractures is either hemiarthroplasty or total hip arthroplasty. The recent National Institute for Health and Care Excellence (NICE) guidance on hip fracture management recommends the use of ‘proven’ cemented stem arthroplasty with an Orthopaedic Device Evaluation Panel (ODEP) rating of at least 3B (97% survival at three years). The Thompsons prosthesis is currently lacking an ODEP rating despite over 50 years of clinical use, likely due to the paucity of implant survival data. Nationally, adherence to these guidelines is varied as there is debate as to which prosthesis optimises patient outcomes.

Plots are an elegant and effective way to represent data. At their best they encourage the reader and promote comprehension. A graphical representation can give a far more intuitive feel to the pattern of results in the study than a list of numerical data, or the result of a statistical calculation.

The temptation to exaggerate differences or relationships between variables by using broken axes, overlaid axes, or inconsistent scaling between plots should be avoided.

A plot should be self-explanatory and not complicated. It should make good use of the available space. The axes should be scaled appropriately and labelled with an appropriate dimension.

Plots are recognised statistical methods of presenting data and usually require specialised statistical software to create them. The statistical analysis and methods to generate the plots are as important as the methodology of the study itself. The software, including dates and version numbers, as well as statistical tests should be appropriately referenced.

Following some of the guidance provided in this article will enhance a manuscript.

Cite this article: Bone Joint J 2015;97-B:1593–1603.

Sciatic nerve palsy following total hip arthroplasty (THA) is a relatively rare yet potentially devastating complication. The purpose of this case series was to report the results of patients with a sciatic nerve palsy who presented between 2000 and 2010, following primary and revision THA and were treated with neurolysis. A retrospective review was made of 12 patients (eight women and four men), with sciatic nerve palsy following THA. The mean age of the patients was 62.7 years (50 to 72; standard deviation 6.9). They underwent interfascicular neurolysis for sciatic nerve palsy, after failing a trial of non-operative treatment for a minimum of six months. Following surgery, a statistically and clinically significant improvement in motor function was seen in all patients. The mean peroneal nerve score function improved from 0.42 (0 to 3) to 3 (1 to 5) (p < 0.001). The mean tibial nerve motor function score improved from 1.75 (1 to 4) to 3.92 (3 to 5) (p = 0.02).The mean improvement in sensory function was a clinically negligible 1 out of 5 in all patients. In total, 11 patients reported improvement in their pain following surgery.

We conclude that neurolysis of the sciatic nerve has a favourable prognosis in patients with a sciatic nerve palsy following THA. Our findings suggest that surgery should not be delayed for > 12 months following injury.

Cite this article: Bone Joint J 2015;97-B:1345–9

Unicompartmental knee arthroplasty (UKA) has advantages over total knee arthroplasty but national joint registries report a significantly higher revision rate for UKA. As a result, most surgeons are highly selective, offering UKA only to a small proportion (up to 5%) of patients requiring arthroplasty of the knee, and consequently performing few each year. However, surgeons with large UKA practices have the lowest rates of revision. The overall size of the practice is often beyond the surgeon’s control, therefore case volume may only be increased by broadening the indications for surgery, and offering UKA to a greater proportion of patients requiring arthroplasty of the knee.

The aim of this study was to determine the optimal UKA usage (defined as the percentage of knee arthroplasty practice comprised by UKA) to minimise the rate of revision in a sample of 41 986 records from the for National Joint Registry for England and Wales (NJR).

UKA usage has a complex, non-linear relationship with the rate of revision. Acceptable results are achieved with the use of 20% or more. Optimal results are achieved with usage between 40% and 60%. Surgeons with the lowest usage (up to 5%) have the highest rates of revision. With optimal usage, using the most commonly used implant, five-year survival is 96% (95% confidence interval (CI) 94.9 to 96.0), compared with 90% (95% CI 88.4 to 91.6) with low usage (5%) previously considered ideal.

The rate of revision of UKA is highest with low usage, implying the use of narrow, and perhaps inappropriate, indications. The widespread use of broad indications, using appropriate implants, would give patients the advantages of UKA, without the high rate of revision.

Cite this article: Bone Joint J 2015;97-B:1506–11.

The August 2015 Oncology Roundup³⁶⁰ looks at: Glasgow prognostic score in soft-tissue sarcoma; Denosumab in giant cell tumour; Timing, complications and radiotherapy; Pigmented villonodular synovitis and arthroscopy; PATHFx: estimating survival in pathological cancer; Prosthetic lengthening of short stumps; Chondrosarcoma and pathological fracture

We describe the outcome of tibial diaphyseal fractures in the elderly (≥ 65 years of age). We prospectively followed 233 fractures in 225 elderly patients over a minimum ten-year period. Demographic and descriptive data were acquired from a prospective trauma database. Mortality status was obtained from the General Register Office database for Scotland. Diaphyseal fractures of the tibia in the elderly occurred predominantly in women (73%) and after a fall (61%). During the study period the incidence of these fractures decreased, nearly halving in number. The 120-day and one-year unadjusted mortality rates were 17% and 27%, respectively, and were significantly greater in patients with an open fracture (p < 0.001). The overall standardised mortality ratio (SMR) was significantly increased (SMR 4.4, p < 0.001) relative to the population at risk, and was greatest for elderly women (SMR 8.1, p < 0.001). These frailer patients had more severe injuries, with an increased rate of open fractures (30%), and suffered a greater rate of nonunion (10%).

Tibial diaphyseal fractures in the elderly are most common in women after a fall, are more likely to be open than in the rest of the population, and are associated with a high incidence of nonunion and mortality.

Cite this article: Bone Joint J 2013;95-B:1255–62.

We assessed the age-related differences in the use of total shoulder arthroplasty (TSA) and outcomes, and associated time-trends using the United States Nationwide Inpatient Sample (NIS) between 1998 and 2010. Age was categorised as < 50, 50 to 64, 65 to 79 and ≥ 80 years. Time-trends in the use of TSA were compared using logistic regression or the Cochran Armitage test.

The overall use of TSA increased from 2.96/100 000 in 1998 to 12.68/100 000 in 2010. Significantly lower rates were noted between 2009 and 2010, compared with between 1998 and 2000, for: mortality, 0.1% versus 0.2% (p = 0.004); discharge to an inpatient facility, 13.3% versus 14.5% (p = 0.039), and hospital stay > median, 29.4% versus 51.2% (p < 0.001).

The rates of use of TSA/100 000 by age groups, < 50, 50 to 64, 65 to 79 and ≥ 80 years were: 0.32, 4.62, 17.82 and 12.56, respectively in 1998 (p < 0.001); and 0.65, 17.49, 75.27 and 49.05, respectively in 2010 (p < 0.001) with an increasing age-related difference over time (p <  0.001). Across the age categories, there were significant differences in the proportion: discharged to an inpatient facility, 3.2% versus 4.2% versus 14.7% versus 36.5%, respectively in 1998 (p < 0.001) and 1.8% versus 4.3% versus 12.5% versus 35.5%, respectively in 2010 (p <  0.001) and the proportion with hospital stay > median, 39.7% versus 40.2% versus 53% versus 69%, respectively in 1998 (p < 0.001) and 17.2% versus 20.6% versus 28.7% versus 50.7%, respectively in 2010 (p < 0.001).

In a nationally representative sample, we noted a time-related increase in the use of TSA and increasing age-related differences in outcomes indicating a changing epidemiology of the use of TSA. Age-related differences in outcomes suggest that attention should focus on groups with the worst outcomes.

Cite this article: Bone Joint J 2015;97-B:1385–9.

It is becoming increasingly common for a patient to have ipsilateral hip and knee replacements. The inter-prosthetic (IP) distance, the distance between the tips of hip and knee prostheses, has been thought to be associated with an increased risk of IP fracture. Small gap distances are generally assumed to act as stress risers, although there is no real biomechanical evidence to support this.

The purpose of this study was to evaluate the influence of IP distance, cortical thickness and bone mineral density on the likelihood of an IP femoral fracture.

A total of 18 human femur specimens were randomised into three groups by bone density and cortical thickness. For each group, a defined IP distance of 35 mm, 80 mm or 160 mm was created by choosing the appropriate lengths of component. The maximum fracture strength was determined using a four-point bending test.

The fracture force of all three groups was similar (p = 0.498). There was a highly significant correlation between the cortical area and the fracture strength (r = 0.804, p <  0.001), whereas bone density showed no influence.

This study suggests that the IP distance has little influence on fracture strength in IP femoral fractures: the thickness of the cortex seems to be the decisive factor.

Cite this article: Bone Joint J 2014;96-B:1378–84.

We investigated the changes seen on serial metal artefact reduction magnetic resonance imaging scans (MARS-MRI) of metal-on-metal total hip arthroplasties (MoM THAs). In total 155 THAs, in 35 male and 100 female patients (mean age 70.4 years, 42 to 91), underwent at least two MRI scans at a mean interval of 14.6 months (2.6 to 57.1), at a mean of 48.2 months (3.5 to 93.3) after primary hip surgery. Scans were graded using a modification of the Oxford classification. Progression of disease was defined as an increase in grade or a minimum 10% increase in fluid lesion volume at second scan. A total of 16 hips (30%) initially classified as ‘normal’ developed an abnormality on the second scan. Of those with ‘isolated trochanteric fluid’ 9 (47%) underwent disease progression, as did 7 (58%) of ‘effusions’. A total of 54 (77%) of hips initially classified as showing adverse reactions to metal debris (ARMD) progressed, with higher rates of progression in higher grades. Disease progression was associated with high blood cobalt levels or an irregular pseudocapsule lining at the initial scan. There was no association with changes in functional scores. Adverse reactions to metal debris in MoM THAs may not be as benign as previous reports have suggested. Close radiological follow-up is recommended, particularly in high-risk groups.

Cite this article: Bone Joint J 2015;97-B:1328–37.

We present detailed information about early morbidity after aseptic revision knee replacement from a nationwide study. All aseptic revision knee replacements undertaken between 1st October 2009 and 30th September 2011 were analysed using the Danish National Patient Registry with additional information from the Danish Knee Arthroplasty Registry. The 1218 revisions involving 1165 patients were subdivided into total revisions, large partial revisions, partial revisions and revisions of unicondylar replacements (UKR revisions). The mean age was 65.0 years (27 to 94) and the median length of hospital stay was four days (interquartile range: 3 to 5), with a 90 days re-admission rate of 9.9%, re-operation rate of 3.5% and mortality rate of 0.2%. The age ranges of 51 to 55 years (p = 0.018), 76 to 80 years (p < 0.001) and ≥ 81 years (p < 0.001) were related to an increased risk of re-admission. The age ranges of 76 to 80 years (p = 0.018) and the large partial revision subgroup (p = 0.073) were related to an increased risk of re-operation. The ages from 76 to 80 years (p < 0.001), age ≥ 81 years (p < 0.001) and surgical time > 120 min (p <  0.001) were related to increased length of hospital stay, whereas the use of a tourniquet (p = 0.008) and surgery in a low volume centre (p = 0.013) were related to shorter length of stay.

In conclusion, we found a similar incidence of early post-operative morbidity after aseptic knee revisions as has been reported after primary procedures. This suggests that a length of hospital stay ≤ four days and discharge home at that time is safe following aseptic knee revision surgery in Denmark.

Cite this article: Bone Joint J 2014;96-B:1649–56.

Objectives

Patient function after arthroplasty should ideally quickly improve. It is not known which peri-operative function assessments predict length of stay (LOS) and short-term functional recovery. The objective of this study was to identify peri-operative functions assessments predictive of hospital LOS and short-term function after hospital discharge in hip or knee arthroplasty patients.

The June 2015 Research Roundup360 looks at: Tranexamic acid: just give it – it’s not important how!; The anterolateral ligament re-examined; Warfarin a poor post-operative agent; Passive exoskeleton the orthosis of the future?; Musculoskeletal medicine: a dark art to UK medical students?; Alendronic acid and bone density post arthroplasty; Apples with oranges? Knee functional scores revisited

The June 2015 Wrist & Hand Roundup360 looks at: Collagenase and Dupuytren’s disease – a genuine alternative to surgery?; iPad PROMise?; Should we learn how to do endoscopic carpal tunnel release?; Two-week radiographs a relic of the past?; Bible? Aspirate or excise?; Patient expectations and trapeziometacarpal osteoarthritis; Splintage in the treatment of sagittal band incompetence and extensor tendon subluxation

We aimed to determine whether cemented hemiarthroplasty is associated with a higher post-operative mortality and rate of re-operation when compared with uncemented hemiarthroplasty. Data on 19 669 patients, who were treated with a hemiarthroplasty following a fracture of the hip in a nine-year period from 2002 to 2011, were extracted from NHS Scotland’s acute admission database (Scottish Morbidity Record, SMR01). We investigated the rate of mortality at day 0, 1, 7, 30, 120 and one-year post-operatively using 12 case-mix variables to determine the independent effect of the method of fixation. At day 0, those with a cemented hemiarthroplasty had a higher rate of mortality (p < 0.001) compared with those with an uncemented hemiarthroplasty, equivalent to one extra death per 424 procedures. By day one this had become one extra death per 338 procedures. Increasing age and the five-year co-morbidity score were noted as independent risk factors. By day seven, the cumulative rate of mortality was less for cemented hemiarthroplasty though this did not reach significance until day 120. The rate of re-operation was significantly higher for uncemented hemiarthroplasty. Despite adjusting for 12 confounding variables, these only accounted for 15% of the observed variability.

The debate about the choice of the method of fixation for a hemiarthroplasty with respect to the rate of mortality or the risk of re-operation may be largely superfluous. Our results suggest that uncemented hemiarthroplasties may have a role to play in elderly patients with significant co-morbid disease.

Cite this article: Bone Joint J 2014;96-B:1185–91.

The best method of managing a fracture of the distal humerus in a frail low-demand patient with osteoporotic bone remains controversial. Total elbow arthroplasty (TEA) has been recommended for patients in whom open reduction and internal fixation (ORIF) is not possible. Conservative methods of treatment, including the ‘bag of bones’ technique (acceptance of displacement of the bony fragments and early mobilisation), are now rarely considered as they are believed to give a poor functional result.

We reviewed 40 elderly and low-demand patients (aged 50 to 93 years, 72% women) with a fracture of the distal humerus who had been treated conservatively at our hospital between March 2008 and December 2013, and assessed their short- and medium-term functional outcome.

In the short-term, the mean Broberg and Morrey score improved from 42 points (poor; 23 to 80) at six weeks after injury to 67 points (fair; 40 to 88) by three months.

In the medium-term, surviving patients (n = 20) had a mean Oxford elbow score of 30 points (7 to 48) at four years and a mean Disabilities of the Arm, Shoulder and Hand score of 38 points (0 to 75): 95% reported a functional range of elbow flexion. The cumulative rate of fracture union at one year was 53%. The mortality at five years approached 40%.

Conservative management of a fracture of the distal humerus in a low-demand patient only gives a modest functional result, but avoids the substantial surgical risks associated with primary ORIF or TEA.

Cite this article: Bone Joint J 2015;97-B:1132–8.

This paper investigates whether cortical comminution and intra-articular involvement can predict displacement in distal radius fractures by using a classification that includes volar comminution as a separate parameter.

A prospective multicentre study involving non-operative treatment of distal radius fractures in 387 patients aged between 15 and 74 years (398 fractures) was conducted. The presence of cortical comminution and intra-articular involvement according to the Buttazzoni classification is described. Minimally displaced fractures were treated with immobilisation in a cast while displaced fractures underwent closed reduction with subsequent immobilisation. Radiographs were obtained after reduction, at 10 to 14 days and after union. The outcome measure was re-displacement or union.

In fractures with volar comminution (Buttazzoni type 4), 96% (53 of 55) displaced. In intra-articular fractures without volar comminution (Buttazzoni 3), 72% (84 of 117) displaced. In extra-articular fractures with isolated dorsal comminution (Buttazzoni 2), 73% (106 of 145) displaced while in non-comminuted fractures (Buttazzoni 1), 16 % (13 of 81 ) displaced.

A total of 32% (53 of 165) of initially minimally displaced fractures later displaced. All of the initially displaced volarly comminuted fractures re-displaced. Displacement occurred in 31% (63 of 205) of fractures that were still in good alignment after 10 to 14 days.

Regression analysis showed that volar and dorsal comminution predicted later displacement, while intra-articular involvement did not predict displacement. Volar comminution was the strongest predictor of displacement.

Cite this article: Bone Joint J 2014;96-B:978–83.

The April 2015 Children’s orthopaedics Roundup³⁶⁰ looks at: Reducing the incidence of DDH – is ‘back carrying’ the answer?; Surgical approach and AVN may not be linked in DDH; First year routine radiographic follow up for scoliosis not necessary; Diagnosis of osteochondritis dessicans; Telemedicine in paediatrics; Regional anesthesia in supracondylar fractures?

The aim of this study was to investigate the relationship between the geometry of the proximal femur and the incidence of intra-operative fracture during uncemented total hip arthroplasty (THA).

We studied the pre-operative CT scans of 100 patients undergoing THA with an uncemented femoral component. We measured the anteroposterior and mediolateral dimensions at the level of division of the femoral neck to calculate the aspect ratio of the femur. Wide variations in the shape of the femur were observed, from round, to very narrow elliptic. The femurs of women were narrower than those of men (p < 0.0001) and small femurs were also narrower than large ones. Patients with an intra-operative fracture of the calcar had smaller and narrower femurs than those without a fracture (p < 0.05) and the implanted Corail stems were smaller in those with a fracture (mean size 9 vs 12, p < 0.0001).

The variability of the shape of the femoral neck at the level of division contributes to the understanding of the causation of intra-operative fractures in uncemented THA.

Cite this article: Bone Joint J 2015;97-B:741–8.

Randomised controlled trials (RCTs) that assessed the efficacy of bracing for adolescent idiopathic scoliosis have suffered from small sample sizes, low compliance and lack of willingness to participate. The aim of this study was to assess the feasibility of a comprehensive cohort study for evaluating both the efficacy and the effectiveness of bracing in patients with adolescent idiopathic scoliosis. Patients with curves at greater risk of progression were invited to join a randomised controlled trial. Those who declined were given the option to remain in the study and to choose whether they wished to be braced or observed. Of 87 eligible patients (5 boys and 63 girls) identified over one year, 68 (78%) with mean age of 12.5 years (10 to 15) consented to participate, with a mean follow-up of 168 weeks (0 to 290). Of these, 19 (28%) accepted randomisation. Of those who declined randomisation, 18 (37%) chose a brace. Patients who were more satisfied with their image were more likely to choose bracing (Odds Ratio 4.1; 95% confidence interval 1.1 to 15.0; p = 0.035). This comprehensive cohort study design facilitates the assessment of both efficacy and effectiveness of bracing in patients with adolescent idiopathic scoliosis, which is not feasible in a conventional randomised controlled trial.

Cite this article: Bone Joint J 2015; 97-B:973–81