Aims

Identifying predictors of compartment syndrome in the foot after a fracture of the calcaneus may lead to earlier diagnosis and treatment. The aim of our study was to identify any such predictors.

Objectives

To investigate psychosocial and biomedical outcomes following total hip replacement (THR) and to identify predictors of recovery from THR.

We report the general mortality rate after total knee replacement and identify independent predictors of survival. We studied 2428 patients: there were 1127 men (46%) and 1301 (54%) women with a mean age of 69.3 years (28 to 94). Patients were allocated a predicted life expectancy based on their age and gender.

There were 223 deaths during the study period. This represented an overall survivorship of 99% (95% confidence interval (CI) 98 to 99) at one year, 90% (95% CI 89 to 92) at five years, and 84% (95% CI 82 to 86) at ten years. There was no difference in survival by gender. A greater mortality rate was associated with increasing age (p < 0.001), American Society of Anesthesiologists (ASA) grade (p < 0.001), smoking (p < 0.001), body mass index (BMI) <  20 kg/m² (p < 0.001) and rheumatoid arthritis (p < 0.001). Multivariate modelling confirmed the independent effect of age, ASA grade, BMI, and rheumatoid disease on mortality. Based on the predicted average mortality, 114 patients were predicted to have died, whereas 217 actually died. This resulted in an overall excess standardised mortality ratio of 1.90. Patient mortality after TKR is predicted by their demographics: these could be used to assign an individual mortality risk after surgery.

A prospective study was performed to develop a clinical prediction rule that incorporated demographic and clinical factors predictive of a fracture of the scaphoid. Of 260 consecutive patients with a clinically suspected or radiologically confirmed scaphoid fracture, 223 returned for evaluation two weeks after injury and formed the basis of our analysis. Patients were evaluated within 72 hours of injury and at approximately two and six weeks after injury using clinical assessment and standard radiographs. Demographic data and the results of seven specific tests in the clinical examination were recorded.

There were 116 (52%) men and their mean age was 33 years (13 to 95; sd 17.9). In 62 patients (28%) a scaphoid fracture was confirmed. A logistic regression model identified male gender (p = 0.002), sports injury (p = 0.004), anatomical snuff box pain on ulnar deviation of the wrist within 72 hours of injury (p < 0.001), and scaphoid tubercle tenderness at two weeks (p < 0.001) as independent predictors of fracture. All patients with no pain at the anatomical snuff box on ulnar deviation of the wrist within 72 hours of injury did not have a fracture (n = 72, 32%). With four independently significant factors positive, the risk of fracture was 91%.

Our study has demonstrated that clinical prediction rules have a considerable influence on the probability of a suspected scaphoid fracture. This will help improve the use of supplementary investigations where the diagnosis remains in doubt.

A prospective cohort of 222 patients who underwent revision hip replacement between April 2001 and March 2004 was evaluated to determine predictors of function, pain and activity level between one and two years post-operatively, and to define quality of life outcomes using validated patient reported outcome tools. Predictive models were developed and proportional odds regression analyses were performed to identify factors that predict quality of life outcomes at one and two years post-operatively. The dependent outcome variables were the Western Ontario and McMaster Osteoarthritis Index (WOMAC) function and pain scores, and University of California Los Angeles activity scores. The independent variables included patient demographics, operative factors, and objective quality of life parameters, including pre-operative WOMAC, and the Short Form-12 mental component score. There was a significant improvement (t-test, p < 0.001) in all patient quality of life scores. In the predictive model, factors predictive of improved function (original regression analyses, p < 0.05) included a higher pre-operative WOMAC function score (p < 0.001), age between 60 and 70 years (p < 0.037), male gender (p = 0.017), lower Charnley class (p < 0.001) and aseptic loosening being the indication for revision (p < 0.003). Using the WOMAC pain score as an outcome variable, factors predictive of improvement included the pre-operative WOMAC function score (p = 0.001), age between 60 and 70 years (p = 0.004), male gender (p = 0.005), lower Charnley class (p = 0.001) and no previous revision procedure (p = 0.023). The pre-operative WOMAC function score (p = 0.001), the indication for the operation (p = 0.007), and the operating surgeon (p = 0.008) were significant predictors of the activity assessment at follow-up. Predictors of quality of life outcomes after revision hip replacement were established. Although some patient-specific and surgery-specific variables were important, age, gender, Charnley class and pre-operative WOMAC function score had the most robust associations with outcome

Hip abductor tears(AT) have long been under-recognized, under-reported and under-treated. There is a paucity of data on the prevalence, morphology and associated factors. Patients with “rotator cuff tears of the hip” that are recognized and repaired during total hip arthroplasty(THA) report comparable outcomes to patients with intact abductor tendons at THA.

The study was a retrospective review of 997 primary THA done by a single surgeon from 2012–2022. Incidental findings of AT identified during the anterolateral approach to the hip were documented with patient name, gender, age and diagnosis. The extent and size of the tears of the Gluteus medius and Minimus were recorded. Xrays and MRI's were collected for the 140 patients who had AT and matched 1:1 with respect to age and gender against 140 patients that had documented good muscle quality and integrity. Radiographic measurements (Neck shaft angle, inter-teardrop distance, Pelvis width, trochanteric width and irregularities, bodyweight moment arm and abductor moment arm) were compared between the 2 groups in an effort to determine if any radiographic feature would predict AT.

The prevalence of AT were 14%. Females had statistically more tears than males(18vs10%), while patients over the age of 70y had statistically more tears overall(19,7vs10,4%), but also more Gluteus Medius tears specifically(13,9vs5,3%). Radiographic measurements did not statistically differ between the tear and control group, except for the presence of trochanteric irregularities. MRI's showed that 50% of AT were missed and subsequently identified during surgery.

Abductor tears are still underrecognized and undertreated during THA which can results in inferior outcomes. The surgeon should have an high index of suspicion in elderly females with trochanteric irregularities and although an MRI for every patient won't be feasible, one should always be prepared and equipped to repair the abductor tendons during THA.

Introduction: The aims of this study were to. determine predictors of pain, function and activity level 1–2 years after revision hip arthroplasty and. define quality of life outcomes after revision total hip replacement. Methods: A prospective cohort of 222 patients who underwent revision hip arthroplasty were evaluated. Predictive models were developed and proportional odds regression analyses were performed to identify factors that predict quality of life outcomes at 1 and 2 years post surgery. The dependent outcome variables were WOMAC function, pain and UCLA activity. The independent variables included patient demographic, surgery specific and objective parameters including baseline Western Ontario McMaster Universities (WOMAC) osteoarthritis index, and the Short Form-12 mental component. The Loess method was used to plot the change of WOMAC and SF-12 scores over time. Results: There was a significant improvement (p< 0.001) in all patient quality of life scores from baseline with results plateauing at 1 year. UCLA activity remained static between 1 and 2 years. In the predictive model, higher baseline WOMAC function (p < 0.001), age between 60–70 (p< 0.037), male gender (0.017), lower Charnley class (p < 0.001) and diagnosis of aseptic loosening (p < 0.003) were significant predictors of improved function. When considering WOMAC pain as an outcome variable, factors predictive of improving category outcome included baseline WOMAC function (p= 0.001), age between 60–70 (p< 0.004), male gender (p= 0.005), lower Charnley class (p< 0.001) and no previous revisions (p < 0.023). Baseline WOMAC pain did not predict final pain outcome. Baseline WOMAC function (p=0.001), the indication for the operation (p=0.007), and the operating surgeon were significant predictors of UCLA activity at follow up. Peri or post-operative complications were not an adverse predictor of physical function, pain or activity. Conclusions: Predictors of quality of life outcomes after revision hip replacement-showed that although some patient specific and surgical specific variables were important, age, gender, Charnley class and baseline WOMAC function had the most robust associations with outcomes

Introduction

Surgical reconstruction of deformed Charcot feet carries high risk of non-union, metalwork failure and deformity recurrence. The primary aim of this study was to identify the factors contributing to these complications following hindfoot Charcot reconstructions.

The aim of the study was to evaluate radiological and clinical outcomes of surgical treatment of developmental dysplasia of the hip (DDH) with Periacetabular Osteotomy (PAO) and to determine the values of radiological parameters allowing us to obtain an optimal clinical result.

Radiological evaluation included a standardized AP digital radiograph of the hip joints. Centre edge angle (CEA), medialization, distalization, femoral head coverage (FHC) and ilioischial angle were measured. Clinical evaluation based on HHS, WOMAC, Merle d'Aubigne-Postel scales and Hip Lag Sign. Radiological and clinical evaluation was performed preoperatively and approximately 12 months after the surgery.

Statistically significant (p<0.05) differences in radiological measurements and all clinical scales have been observed pre- and postoperatively for all of the parameters. The results of PAO presented decreased medialization by 3.4mm (range: 3 to 3.7), distalization by 3.5mm (range: 3.2 to 3.8) and the ilioischial angle by 2.7° (range: 2.2 to 3.7). There was also an improvement in the femoral head bone coverage: CEA increased by 16.3° (range: 12.1˚ to 20.5˚) and FHC by 15.2% (range: 10.8 to 19.8). Clinically we observed an increase in HHS by 22 points (range: 15.8 to 28.2) and M. Postel d'Aubigne by 3.5 points (range: 2.0 to 4.4) and a decrease in WOMAC by 24% (range: 22.6 to 25.8). HLS improvement of gluteal muscles’ efficiency has been observed in 67% of patients postoperatively.

This study revealed that the qualification of patients with DDH for an elective PAO is more justified due to the predicted optimal clinical outcomes based on three parameters: CEA <25 degrees, FHC <75%, and ilioischial angle >85.9 degrees. Accordingly, to achieve better clinical results for all scales, it is necessary to increase the average CEA value by 11˚, the average FHC by 11%, and reduce the average ilioischial angle by 3˚.

Use of anticoagulants for thromboembolic prophylaxis is strongly supported by evidence. However, the use of these medications beyond the prophylactic period is poorly understood.

We identified anticoagulant naïve patients that underwent hip or knee replacement between 2012 and 2019 from an arthroplasty registry and probabilistically linked 3,018 surgeries with nationwide pharmaceutical claims data. Rates of anticoagulation use were examined during the early (<= 60 days post-discharge), mid-term (61–180 days post-discharge) and long-term (181–360 days post-discharge) periods. Multivariable logistic regression analysis was performed to identify patient- and surgery-related factors associated with long-term anticoagulant use.

Anticoagulants were supplied to 20% of arthroplasties within 60 days of discharge, 7% between 61–180 days, and 10% between 181–360 days. Older age, obesity, increased comorbidity burden, a longer length of stay, occurrence of a complication necessitating anticoagulation and dispensation of an anticoagulant within 60 days of discharge were all risk factors for long-term anticoagulant use.

Given the risks associated with unnecessary use of these medications, certain patients who are prescribed anticoagulants beyond prophylactic period may benefit from specialist medication review in the months following surgery.

Signal intensity changes of the spinal cord on MRI in chronic cervical myelopathy are thought to be indicative of the prognosis. However, the prognostic significance of signal intensity change remains controversial. The purpose of this study was to investigate the characteristics of MR findings in cervical compression myelopathy that reflect the clinical symptoms and the prognosis and to determine the radiographical and clinical factors that correlate to the prognosis. The subjects were 73 patients who underwent cervical expansive laminoplasty. Their mean age was 64 years, and the mean postoperative follow-up was 3.4 years. The pathological conditions were cervical spondylotic myelopathy in 42 and ossification of the posterior longitudinal ligament in 31.MRI (spin-echo sequence) was performed in all patients. Three patterns of spinal cord signal intensity changes on T1-weighted sequences/T2-weighted sequences were detected as follows: normal/ normal. (N/N); normal/ high signal intensity changes (N/Hi); and low signal intensity changes/high signal intensity changes (Lo/Hi). Surgical outcomes were compared among these three groups. The most useful combination of parameters for predicting prognosis was determined. There were 2 patients with N/N, 67 with N/Hi and 4 with Lo/Hi signal change patterns before surgery. Regarding postoperative recovery, the preoperative Lo/Hi group was significantly inferior to the preoperative N/Hi group. The best combination of predictors for surgical outcomes included age, preoperative signal pattern and duration of symptoms. The low signal intensity changes on T1-weighted sequences indicated a poor prognosis. We speculate that high signal intensity changes on T2-weighted images include a broad spectrum of compressive myelomalacid pathologies and reflect a broad spectrum of recuperative potentials of the spinal cord. Predictors for surgical outcomes are preoperative signal intensity change pattern of the spinal cord on radiological evaluations, age at the time of surgery and chronicity of the disease

Minimally displaced paediatric proximal humerus fractures (PHFs) can be reliably managed non-operatively, however there is considerable debate regarding the appropriate management of severely displaced PHFs, particularly in older children and adolescents with limited remodelling potential. The purpose of this study was to perform a systematic review to answer the questions: “What are the functional and quality-of-life outcomes of paediatric PHFs?” and “What factors have been associated with a poorer outcome?”

A review of Medline and EMBASE was performed on 4^th July 2021 using search terms relevant to PHFs, surgery, non-operative management, paediatrics and outcomes. Studies including ≥10 paediatric patients with PHFs, which assessed clinical outcomes by use of an established outcome measure, were selected. The following clinical information was collected: participant characteristics, treatment, complications, and outcomes.

Twelve articles were selected, including four prospective cohort studies and eight retrospective cohort studies. Favourable outcome scores were found for patients with minimally displaced fractures, and for children aged less than ten years, irrespective of treatment methodology or grade of fracture displacement. Older age at injury and higher grade of fracture displacement were reported as risk factors for a poorer patient-reported outcome score.

An excellent functional outcome can be expected following non-operative management for minimally displaced paediatric PHFs. Prospective trials are required to establish a guideline for the management of severely displaced PHFs in children and adolescents according to fracture displacement and the degree of skeletal maturity.

This study aimed to evaluate the month-to-month prevalence of antibiotic dispensation in the 12 months before and after total knee arthroplasty (TKA) and total hip arthroplasty (THA) and to identify factors associated with antibiotic dispensation in the month immediately following the surgical procedure.

In total, 4,115 THAs and TKAs performed between April 2013 and June 2019 from a state-wide arthroplasty referral centre were analysed. A cross-sectional study used data from an institutional arthroplasty registry, which was linked probabilistically to administrative dispensing data from the Australian Pharmaceutical Benefits Scheme. Multivariable logistic regression was carried out to identify patient and surgical risk factors for oral antibiotic dispensation.

Oral antibiotics were dispensed in 18.3% of patients following primary TKA and 12.0% of patients following THA in the 30 days following discharge. During the year after discharge, 66.7% of TKA patients and 58.2% of THA patients were dispensed an antibiotic at some point. Patients with poor preoperative health status were more likely to have antibiotics dispensed in the month following THA or TKA. Older age, undergoing TKA rather than THA, obesity, inflammatory arthritis, and experiencing an in-hospital wound-related or other infectious complications were associated with increased antibiotic dispensation in the 30 days following discharge.

A high rate of antibiotic dispensation in the 30 days following THA and TKA has been observed. Although resource constraints may limit routine wound review for all patients by a surgeon, a select cohort may benefit from timely specialist review postoperatively. Several risk factors identified in this study may aid in identifying appropriate candidates for such changes to follow-up care.

Aims

Surgical reconstruction of deformed Charcot feet carries a high risk of nonunion, metalwork failure, and deformity recurrence. The primary aim of this study was to identify the factors contributing to these complications following hindfoot Charcot reconstructions.

Introduction: Dural tears are one of the most frequent type of complication in posterior spinal fusion with little known about their predictors. Method: Prospective consecutive study with an evidence level 2++ of 42 patients in the international spine registry Spine Tango, who had been treated between 05/2005 and 8/2008 with posterior spinal fusion after opening of the spinal canal. Median age was 62.7 yrs (min 12.5, max 90.5 yrs) with a female to male ratio of 2:1. In 42 of 1575 cases a dural tear occurred being the most frequent type of complication in our study sample. Multiple linear regression was performed on potential predictor-variables of the occurrence of dural tears. Results: Hospital (p=0.02) and number of segments of fusion (p=0.018) were found to be predictors of the occurrence of dural tears in posterior spinal fusion. Number of fusions per hospital (min 25, max 526) and academic status of hospital had no influence on the rate of dural tears. Fusions of four and more segments showed an increase of the rate of dural tears by three compared to fusions of less than four segments. Conclusion: Predictors of dural tears in posterior spinal fusion are hospital, independent of number of spinal surgeries and academic status of hospital, and number of segments of fusion. In fusions of four and more segments a threefold higher risk of dural tears in comparison to fusions of less than four segments should be taken into consideration

Background

Guidelines recommend epidural steroid injections (ESI) for treating severe disc-related sciatica based on trial data showing modest reductions in leg pain, disability and surgery avoidance. Despite their widespread use, there is no clear evidence about which patients are more likely to benefit from ESI. The aim of this study was to generate consensus on potential predictors of outcome following ESI for disc-related sciatica to include in data collection in a future cohort study.

It is undetermined which factors predict return to work following arthroscopic rotator cuff repair. We aimed to identify which factors predicted return to work at any level, and return to pre-injury levels of work 6 months post-arthroscopic rotator cuff repair.

Multiple logistic regression analysis of prospectively collected demographic, pre-injury, preoperative, and intraoperative data from 1502 consecutive primary arthroscopic rotator cuff repairs, performed by a single surgeon, was performed to identify independent predictors of return to work, and return to pre-injury levels of work respectively, 6 months post-surgery.

Six months post-rotator cuff repair, 76% of patients returned to work (RTW), and 40% returned to pre-injury levels of work (Full-RTW). RTW at 6 months was likely if patients were still working after their injuries, but prior to surgery (Wald statistic [W]=55, p<0.0001), were stronger in internal rotation preoperatively (W=8, p=0.004), had full-thickness tears (W=9, p=0.002), and were female (W=5, p=0.030). Patients who achieved Full-RTW were likely to have worked less strenuously pre-injury (W=173, p<0.0001), worked more strenuously post-injury but pre-surgery (W=22, p<0.0001), had greater behind-the-back lift-off strength preoperatively (W=8, p=0.004), and had less passive external rotation range of motion preoperatively (W=5, p=0.034). Patients who were still working post-injury, but pre-surgery were 1.6-times more likely to RTW than patients who were not (p<0.0001). Patients who nominated their pre-injury level of work as “light” were 11-times more likely to achieve Full-RTW than those who nominated “strenuous” (p<0.0001).

Six months post-rotator cuff repair, a higher patient-rated post-injury, but pre-surgery level of work was the strongest predictor of RTW. A lower patient-rated pre-injury level of work was the strongest predictor of Full-RTW. Greater preoperative subscapularis strength independently predicted both RTW, and Full-RTW.

Same day home (SDH) discharge in total joint arthroplasty (TJA) has increased in popularity in recent years. The objective of this study was to evaluate the causes and predictors of failed discharges in planned SDH patients.

A consecutive cohort of patients who underwent total knee (TKA) or total hip arthroplasty (THA) that were scheduled for SDH discharge between April 1, 2019 to March 31, 2021 were retrospectively reviewed. Patient demographics, causes of failed discharge, perioperative variables, 30-day readmissions and 6-month reoperation rates were collected. Multivariate regression analysis was undertaken to identify independent predictors of failed discharge.

The cohort consisted of 527 consecutive patients. One hundred and one (19%) patients failed SDH discharge. The leading causes were postoperative hypotension (20%) and patients who were ineligible for the SDH pathway (19%). Two individual surgeons, later operative start time (OR 1.3, 95% CI, 1.15-1.55, p=0.001), ASA class IV (OR 3.4, 95% CI, 1.4-8.2; p=0.006) and undergoing a THA (OR 2.0, 95% CI, 1.2-3.1, p=0.004) were independent predictors of failed SDH discharge. No differences in age, BMI, gender, surgical approach or type of anesthetic were found (p>0.05). The 30-day readmission or 6-month reoperation were similar between groups (p>0.05).

Hypotension and inappropriate patient selection were the leading causes of failed SDH discharge. Significant variability existed between individual surgeons failed discharge rates. Patients undergoing a THA, classified as ASA IV or had a later operative start time were all more likely to fail SDH discharge.

True scaphoid fractures of the wrist are difficult to diagnose in children. In 5–40% of cases, a scaphoid fracture may not be detectable on initial X-ray, some fractures may take up to six weeks to become evident. Since missing a scaphoid fracture may have serious implications, many children with a suspected or “clinical” scaphoid fracture, but normal radiographs, may be over-treated. The purpose of this study was to identify predictors of true scaphoid fractures in children.

A retrospective cohort study was performed using electronic medical records for all patients over a two-year period presenting to a tertiary paediatric hospital with hand or wrist injury. Charts were identified by ICD-10 diagnostic codes and reviewed for pre-specified inclusion and exclusion criteria. Patients with either a clinical or true scaphoid fracture were included. When a scaphoid fracture was suspected, but imaging was negative for fracture, the diagnosis of a clinical scaphoid fracture was made. True scaphoid fractures were diagnosed when a fracture was evident on any modality of medical imaging (X-ray, CT, MRI) at any time post-injury.

Over the two-year study period, 148 patients (60 scaphoid fractures, 88 non-fractures) met inclusion and exclusion criteria for review. Mean (±SD) age was 13±2 years and 52% were male. The left wrist was injured in 61% of cases. Of the 60 true scaphoid fractures, mean age was 14±2 years, and 69% were male. Fracture location was primarily at the waist (48%) or distal pole (45%) of the scaphoid. Sports were the prevailing mechanism of injury. Six (11%) underwent surgery. Multivariate logistic regression demonstrated that older age, male gender, and right-sided injury were predictors of scaphoid fracture with odds ratios of 1.3 (95% CI: 1.1–1.6, p=0.005), 2.8 (95% CI: 1.3–6, p=0.007), and 2.4 (95% CI: 1.1–5.2, p=0.025).

Older age, male gender, and right-sided injury may be predictors of scaphoid fractures in children. Further evidence to support this may enable the formulation of clinical guidelines or rules to reduce the overtreatment of children presenting with a clinical scaphoid fracture.

In-hospital length of stay (LOS) and discharge disposition following arthroplasty could act as surrogate measures for improvement in patient pathways, and have major cost saving implications for healthcare providers. With the ever-growing adoption of robotic technology in arthroplasty, we wished to evaluate its impact on LOS. The objectives of this study were to compare LOS and discharge disposition following robotic-arm assisted (RO THA) versus conventional technique Total Hip Arthroplasty (CO THA).

This large-scale, single institution study included patients of any age undergoing primary THA (N = 1,732) for any cause between May 2019 and January 2023. Data extracted included patient demographics, LOS, need for Post Anaesthesia Care Unit (PACU) admission, anaesthesia type, readmission within 30 days and discharge dispositions. Univariate and multivariate logistic regression models were also employed to identify factors and patient characteristics related to delayed discharge.

The median LOS in the RO THA group was 54 hours (34, 78) versus 60 (51, 100) in the CO THA group, p<0.001. Discharge disposition was comparable between the two groups. In the multivariate model, age, need for PACU admission, ASA score > 2, female gender, general anaesthesia and utilisation of the conventional technique were significantly associated with LOS > 2 days.

Our study showed that robotic-arm assistance was associated with a shorter LOS in patients undergoing primary THA and no difference in discharge destination. Our results suggest that robotic-arm assistance could be advantageous in partly addressing the upsurge of hip arthroplasty procedures and the concomitant health care burden; however, this needs to be corroborated by long-term cost effectiveness analyses and data from randomised controlled studies.

Periprosthetic femoral fractures are increasingly seen in recent years, adding considerable burden to the National Health Service. These require complex revision or fixation and prolonged post-operative care, with significant morbidity with associated costs. The purpose of this study was to assess whether the size of femoral cement mantle is associated with periprosthetic femoral fractures (PPF).

This retrospective study was carried out on a cohort of 49 patients (Fracture Group - FG) who previously had a revision procedure following a proximal PPF between 2010 and 2021. Inclusion criteria – all primary cemented total hip replacements (THR). Exclusion criteria – complex primary THR, any implant malposition that required early revision surgery or any pre-fracture stem loosening. The antero-posterior (AP) radiographs from this cohort of patients were assessed and compared to an age, sex, time since THR-matched control group of 49 patients without PPF (Control Group - CG). Distal cement mantle area (DCMA) was calculated on an AP radiograph of hip; the position of the femoral stem tip prior to fracture was also recorded: valgus, varus or central. Limitations: AP radiographs only. Statistical analyses were performed using Microsoft® Excel.

Chi-square test demonstrated statistically significant difference in DCMA between FG and CG. DCMA of 700 to 900 mm² appeared to be protective when compared to DCMA of 0 to 300 mm². Also, a valgus position observed in 23% in FG Vs 4 % in CG increased the risk, with a smaller area of DCMA.

This study demonstrates and recommends that a size of 700 – 900 mm² of the DCMA is protective against periprosthetic fractures, which are further influenced by the positioning of the distal stem tip. This could be due to the gradual decrease in the stiffness gradient from proximal to distal around the stem tip than steep changes, thereby decreasing possibility of a stress riser just distal to the cement mantle or restrictor. Further biomechanical research specific to this finding may be helpful to validate the observation, progressing to suggest a safe standardised surgical technique.

Total hip arthroplasty has been constantly evolving with technological improvements to achieve the best survival rates. Although the new implants are under closer surveillance through processes such as Beyond Compliance, orthopaedic surgeons generally tend to look out for the latest implants with good short-term results and hope for better long-term results for these. We questioned whether such an assumption or bias is valid.

We analysed the data of Kaplan-Meier estimates of cumulative revisions of primary hip replacement by fixation, stem/cup brand and bearing combinations from the NJR 19th Annual Report published in September 2022. We performed a univariate linear regression analysis to predict the 10- and 15-year revision rates for these different hip implant combinations from the 3- and 5-year revision rates.

Thirty-seven implant combinations had their 15-year revision rates reported and 67 had the 10-year revision rates. The correlation co-efficients were 0.43 and 0.58 for the 3-year and 5-year revision rates against 15-year revision rates. Only 17% of the variance in 15-year revision rates could be predicted by a linear regression model from the 3-year revision rate and 32% from the 5-year revision rate. Corresponding values for the 10-year revision rates were 46% and 67%.

95% prediction intervals for the 15-year revision rate were +/− 3.1% from the 3-year revision rate and +/− 2.8% from the 5-year revision rate. Corresponding values for the 10-year revision rates were +/− 1.3% and +/− 1%.

19 of 37 implant combinations showed 15-year revision rate of more than 4%. Average 3-year and 5-year revision rates for this cohort was 1.0% and 1.42% compared to 1.4% and 1.9% for the rest and the difference was statistically significant.

Although average early revision rates showed small but significant difference between the groups with lower and higher 15-year revision rates, the prediction intervals for 15-year revision rates for individual hips based on their 3-year and 5-year revision rates are very wide. Three- and 5-year revision rates for primary total hip replacements are poor predictors of 15-year revision rates.

Posterior spinal surgery is associated with a significant amount of blood loss. The factors predisposing the patient to excessive bleeding-and therefore transfusion- are not well established nor is the effect of transfusion on the outcomes following spinal surgery. We had two goals in this study. First, we were to investigate any suspected risk factors of transfusion in posterior thoraco-lumbar fusion patients. Second, we wanted to observe the negative impact-if one existed- of transfusion on the outcomes of surgery

All adults undergoing posterior thoraco-lumbar spine fusion in our institution from May 2015 to May 2018 were included. Data collected included demographic data as well as BMI, preoperative hemoglobin, American Society of Anesthesiologists classification (ASA), delta Hemoglobin, estimated blood loss, incidence of transfusion, number of units transfused, number of levels fused, length of stay and re-admission within 30 days. The data was analyzed to correlate these variables with the frequency of transfusion and then to assess the association of adverse outcomes with transfusion.

125 patients were included in the study. Only 6 patients (4.8%) required re-admission within the first 30 days after discharge. Length of stay averaged 8.4 days (3–74). 18 patients (14.4%) required transfusion peri-operatively. When multiple variables were analyzed for any correlation, the number of levels fused, age and BMI had statistically significant correlation with the need for transfusion (P <0.005)

Patients undergoing posterior thoraco-lumbar fusion are more likely to require blood transfusion if they were older, over-weight & obese or had a multi-level fusion. Receiving blood transfusion is associated with increased complication rates.

While total joint replacement (TJR) is considered as an effective intervention to relieve pain and restore joint function for end-stage osteoarthritis (OA) patients, a significant proportion of the patients are dissatisfied with their surgery outcomes. The aim of this study was to identify genetic factors that can predict patients who do or do not benefit from these surgical procedures by a genome-wide association study (GWAS).

Study participants were derived from the Newfoundland Osteoarthritis Study (NFOAS) which consisted of 1086 TJR patients. Non-responders to TJR was defined as patients who did not reach the minimum clinically important difference (MCID) based on the self administered Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) in terms of pain reduction or function improvment. DNA was extracted from the blood samples of the study participants and genotyped by Illumina GWAS genotyping platform. Over two million single nucleotide polymorphisms (SNPs) across the genome were genotyped and tested for assocition with non-responders.

39 non-responders and 44 age, sex, and BMI matched responders were included in this study. Four chromosome regions on chromosomes 5, 7, 8, and 12 were suggested to be associated with non-responders with p < 1 0–5. The most promising one was on chromosome 5 with the lead SNP rs17118094 (p=1.7×10–6) which can classify 72% of non-responders accurately. The discriminatory power of this SNP alone is very promising as indicated by an area under the curve (AUC) of 0.72 with 95% confidence interval of 0.63 to 0.81, which is much better than any previously studied predictors mentioned above. All the patients who carry two copies of the G allele (minor allele) of rs17118094 were non-responders and 75% of those who carry one copy of the G allele were non-responders. The discriminatory ability of the lead SNPs on chromosomes 7 and 12 were comparable to the one on chromosome 5 with an AUC of 0.74, and 88% of patients who carry two copies of the A allele of rs10244798 on chromosome 7 were non-responders. Similarly, 88% of patients who carry two copies of the C allele of rs10773476 on chromosome 12 were non-responders. While the discriminatory ability of rs9643244 on chromosome 8 was poor with an AUC of 0.26, its strong association with non-responders warrants a further investigation in the region.

The study identified four genomic regions harboring genetic factors for non-responders to TJR. The lead SNPs in those regions have great discriminatory ability to predict non-responders and could be used to create a genetic prediction model for clinical unitilty and application.

Aims

The primary aim of this study was to assess if traumatic triangular fibrocartilage complex (TFCC) tears can be treated successfully with immobilization alone. Our secondary aims were to identify clinical factors that may predict a poor prognosis.

Aims

With novel promising therapies potentially limiting progression of Dupuytren’s disease (DD), better patient stratification is needed. We aimed to quantify DD development and progression after seven years in a population-based cohort, and to identify factors predictive of disease development or progression.

Aims

Sickle cell disease (SCD) is an autosomal recessive inherited condition that presents with a number of clinical manifestations that include musculoskeletal manifestations (MM). MM may present differently in different individuals and settings and the predictors are not well known. Herein, we aimed at determining the predictors of MM in patients with SCD at the University Teaching Hospital, Lusaka, Zambia.

Aims

Historically, patients undergoing surgery for adolescent idiopathic scoliosis (AIS) have been nursed postoperatively in a critical care (CC) setting because of the challenges posed by prone positioning, extensive exposures, prolonged operating times, significant blood loss, major intraoperative fluid shifts, cardiopulmonary complications, and difficulty in postoperative pain management. The primary aim of this paper was to determine whether a scoring system, which uses Cobb angle, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and number of levels to be fused, is a valid method of predicting the need for postoperative critical care in AIS patients who are to undergo scoliosis correction with posterior spinal fusion (PSF).

Aims

Repeated lumbar spine surgery has been associated with inferior clinical outcomes. This study aimed to examine and quantify the impact of this association in a national clinical register cohort.

Source of the study: University of Auckland, Auckland, New Zealand and University of Otago, Christchurch, New Zealand

The Oxford Knee Score (OKS) is a 12-item questionnaire used to track knee arthroplasty outcomes. Validation of such patient reported outcome measures is typically anchored to a single question based on patient ‘satisfaction’, however risk of subsequent revision surgery is also an important outcome measure. The OKS can predict subsequent revision risk within two years, however it is not known which item(s) are the strongest predictors. Our aim was to identify which questions were most relevant in the prediction of subsequent knee arthroplasty revision risk.

All primary TKAs (n=27,708) and UKAs (n=8,415) captured by the New Zealand Joint Registry between 1999 and 2019 with at least one OKS response at six months, five years or ten years post-surgery were included. Logistic regression and receiver operating characteristics (ROC) curves were used to assess prediction models at six months, five years and ten years.

Q1 ‘overall pain’ was the strongest predictor of revision within two years (TKA: 6 months, odds ratio (OR) 1.37; 5 years, OR 1.80; 10 years, OR 1.43; UKA: 6 months, OR 1.32; 5 years, OR 2.88; 10 years, OR 1.85; all p<0.05). A reduced model with just three questions (Q1, Q6 ‘limping when walking’, Q10 ‘knee giving way’) showed comparable or better diagnostic ability with the full OKS (area under the curve (AUC): TKA: 6 months, 0.77 vs. 0.76; 5 years, 0.78 vs. 0.75; 10 years, 0.76 vs. 0.73; UKA: 6 months, 0.80 vs. 0.78; 5 years: 0.81 vs. 0.77; 10 years, 0.80 vs. 0.77).

The three questions on overall knee pain, limping when walking, and knee ‘giving way’ were the strongest predictors of subsequent revision within two years. Attention to the responses for these three key questions during follow-up may allow for prompt identification of patients most at risk of revision.

Aims

The aims of this study were to assess mapping models to predict the three-level version of EuroQoL five-dimension utility index (EQ-5D-3L) from the Oxford Knee Score (OKS) and validate these before and after total knee arthroplasty (TKA).

Aims

The primary aim was to assess the independent influence of coronavirus disease (COVID-19) on 30-day mortality for patients with a hip fracture. The secondary aims were to determine whether: 1) there were clinical predictors of COVID-19 status; and 2) whether social lockdown influenced the incidence and epidemiology of hip fractures.

Avascular necrosis (AVN) of the femoral head is a potentially devastating complication of treatment for developmental dysplasia of the hip (DDH). AVN most commonly occurs following operative management by closed (CR) or open reduction (OR). This occurrence has frequently been examined in single centre, retrospective studies, however, little high-level evidence exists to provide insight on potential risk factors. The purpose of this observational, prospective multi-centre study was to identify predictors of AVN following operatively-managed DDH.

A multi-centre, prospective database of infants diagnosed with DDH from 0–18 months was analyzed for patients treated by CR and/or OR. At minimum one year follow-up, the incidence of AVN (Salter criteria) was determined from AP pelvis radiographs via blinded assessment and consensus discussion between three senior paediatric orthopaedic surgeons. Patient demographics, clinical exam findings and radiographic data were assessed for potential predictors of AVN.

A total of 139 hips in 125 patients (102 female, 23 male) underwent CR/OR at a median age of 10.4 months (range 0.7–27.9). AVN was identified in 37 cases (26.6% incidence) at a median 23 months post-surgery. Univariate logistic regression analysis comparing AVN and no AVN groups identified sex, age at diagnosis, age at surgery, pre-surgery IHDI grade and time between diagnosis and surgery as potential predictive factors. Specifically, male sex (OR 2.21 [0.87,5.72]), IHDI grade IV, and older age at diagnosis (7.4 vs. 9.5 months) and surgery (10.2 vs. 13.6 months) were associated with development of AVN. Likewise, increased time between diagnosis and surgery (2.9 vs. 5.5 months) was also associated with a higher incidence. No association was found with surgery type (CR vs. OR), pre-surgery acetabular index or surgical hip.

Development of AVN occurred in 26.6% of hips undergoing CR or OR at a median 23 months post-surgery. Male sex, older age at diagnosis and surgery, dislocation severity and increased time between diagnosis and surgery were associated with AVN. Longer-term follow-up and larger numbers will be required to confirm these findings. Early outcomes from this prospective patient cohort suggest that AVN is an important complication of operative management for DDH, and appears to occur at a comparable rate whether the reduction is performed open or closed. Male patients may be more susceptible to developing AVN and merits further exploration. Potential predictive factors of older age and length of time between diagnosis and surgery emphasize the importance of early detection and treatment to minimize complications and optimize outcomes.

Solitary fibrous tumor (SFT) is a rare mesenchymal tumor with an intermediate tendency to metastasize, which is found in many different locations including head and neck, abdomen, chest cavity and extremities. Also, meningeal hemangiopericytoma (HPC) is considered an SFT which arises in the meningeal membranes. SFT family shows an undetermined biologic behavior varying from a silent indolent tumor to an aggressive malignant form; however, benign and malignant variants of SFT may have similar cytopathologic characteristics. In this study, we defined the factors correlated with SFT's aggressive behavior and patient's survival.

This is a retrospective study based on medical records of 85 patients who were suffering from SFT and had been treated at McGill University Health Centre (MUHC) between 1984 and 2017. We used multivariate logistic regression analysis to address any association between the variables including patient's demographics, tumor size, primary location of the tumor, pathological features, treatment methods and outcomes.

The median of the follow-up period was 60 months. The patient's age or gender had no association with tumor aggressive behavior or patient's survival. Anatomical origin of primary tumor had no strong correlation with the patient's disease related death (DRD); however, tumors originated from CNS showed more aggressive behavior. There was an association between tumor size more than 7 cm and distant metastasis (MT) (p= 0.03) and DRD (p=0.03). The tumor size also correlated with the 5-year disease-free survival (p=0.017). We had three histologic groups: 1- Benign SFT (30 cases), 2- cellular SFT or HPC (29 cases), 3- malignant SFT or anaplastic HPC (26 cases). Although univariate analysis demonstrates that patients suffering from cellular SFT and malignant SFT showed increased aggressive behavior of the tumor, multivariate analysis didn't verify the mentioned association. Patients with positive margins had increased odds ratio to experience tumor local recurrence (LR) (p= 0.05) and LR was correlated with DRD in our patients (p=0.006). Radiotherapy had no statistical association with LR, MT or DRD. Frequency of LR and MT in the study were 25.7% and 29.8% respectively. 5-year disease-free survival in our patients was 76%.

The size of SFT is the most correlative predictor of the tumor's aggressive behavior. The local recurrence of SFT is associated with disease related death; therefore, resection of the tumor with negative margins provides the highest chance of cure. In addition, a cellular SFT should be treated like a malignant variant of the tumor.

Distal radius fractures are the most common adult fractures, yet there remains some uncertainty surrounding optimal treatment modalities. Recently, the rate of operative treatment of these injuries has been increasing, however, predictors of outcomes in patients treated surgically remain poorly understood. The purpose of this study was to evaluate independent predictors of 30-day readmission and complications following internal fixation of distal radius fractures.

Patients ≥18 years who underwent surgical intervention for distal radius fractures between 2005 and 2016 were identified from the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) using procedural codes. Patient demographics, as well as 30-day readmission, complication, and mortality rates were ascertained. Multivariable logistic regression was used to determine independent predictors of 30-day outcomes while adjusting for patient age, sex, American Society of Anaesthesiologists (ASA) class, functional status, smoking status, comorbidities, and Body Mass Index (BMI).

A total of 10,051 patients were identified (average age 58 ±16). All patients received open reduction and internal fixation with no cases of external fixation identified in the data set. Included fractures were 37% extraarticular and 63% intraarticular. Within 30-days of initial fixation 143 (1.42%) patients were readmitted to the hospital, 71 patients experienced a complication, and 18 (0.18%) patients died. After adjusting for relevant covariables, current smoking increased the odds of readmission by 1.73 (95%Confidence interval [95%CI] 1.15 – 2.50), ASA class III/IV vs. I/II increased the odds of readmission by 2.74 (95%CI 1.85 – 4.06), and inpatient surgery vs. outpatient surgery increased the odds of readmission by 2.10 (95%CI 1.46 – 3.03). Current smoking also increased the odds of complications by 2.26 (95%CI 1.32 – 3.87), while ASA class III/IV increased it by 2.78 (95%CI 1.60 – 4.85), inpatient surgery increased it by 2.26 (95%CI 1.37 – 3.74), and dependent functional status increased it by 2.55 (1.16 – 5.64).

In conclusion, patients with severe systemic disease, current smokers and patients undergoing inpatient surgery are at risk for 30-day readmissions and complications following operative treatment of distal radius fractures. In addition, patients with dependent functional statuses are more likely to experience a complication within 30-days.

Aims

The aim of this study was to develop and internally validate a prognostic nomogram to predict the probability of gaining a functional range of motion (ROM ≥ 120°) after open arthrolysis of the elbow in patients with post-traumatic stiffness of the elbow.

Introduction

With the removal of total hip arthroplasty (THA) from the Centers for Medicare & Medicaid Services (CMS) inpatient-only list, understanding predictors of length of stay (LOS) after THA is critical. Thus, we aimed to determine the influence of patient- and procedure-related risk factors as predictors of >1-day LOS after THA.

Background

Readmission following any total joint arthroplasty has become a closely watched metric for many hospitals in the United States because financial penalties imposed by CMS for excessive readmissions occurring within thirty days of discharge has occurred since 2015. The purpose of this study was to identify both preoperative comorbidities associated with and postoperative reasons for readmission within thirty days following primary total joint arthroplasty in the lower extremity.

This international multicentre retrospective cohort study aimed to assess: 1) prevalence of COVID-19 in hip fracture patients, 2) effect on mortality, and 3) clinical factors associated mortality among COVID-19-positive patients.

A collaboration among 112 centres in 14 nations collected data on all patients with a hip fracture between 1st March-31st May 2020. Patient, injury and surgical factors were recorded, and outcome measures included admission duration, COVID-19 and 30-day mortality status.

There were 7090 patients and 651 (9.2%) were COVID-19-positive. COVID-19 was independently associated with male sex (p=0.001), residential care (p<0.001), inpatient fall (p=0.003), cancer (p=0.009), ASA grade 4–5 (p=0.008; p<0.001), and longer admission (p<0.001). Patients with COVID-19 had a significantly lower chance of 30-day survival versus those without (72.7% versus 92.6%, p<0.001), and COVID-19 was independently associated with increased 30-day mortality risk (p<0.001). Increasing age (p=0.028), male sex (p<0.001), renal (p=0.017) and pulmonary disease (p=0·039) were independently associated with higher 30-day mortality risk in patients with COVID-19 when adjusting for confounders.

The prevalence of COVID-19 in hip fracture patients was 9% and was independently associated with a three-fold increased 30-day mortality risk. Clinical factors associated with mortality among COVID-19-positive hip fracture patients were identified for the first time. This is the largest study, and the only global cohort, reporting on the effect of COVID-19 in hip fracture patients. The findings provide a benchmark against which to determine vaccine efficacy in this vulnerable population and are especially important in the context of incomplete vaccination programmes and the emergence of vaccine-resistant strains.

Aims

Fracture of the odontoid process (OP) in the elderly is associated with mortality rates similar to those of hip fracture. The aim of this study was to identify variables that predict mortality in patients with a fracture of the OP, and to assess whether established hip fracture scoring systems such as the Nottingham Hip Fracture Score (NHFS) or Sernbo Score might also be used as predictors of mortality in these patients.

Purpose and background

Acute and chronic spinal pain are major causes of disability, and many patients use analgesics to treat their pain. However, increased use of analgesics, particularly prescription opioids have the potential to be overused and cause dependence. Psychological factors such as stress, anxiety, depression, pain acceptance, pain catastrophising and alexithymia influence both the pain response and analgesic use, yet to date no studies have explored these variables in spinal pain patients. Therefore, the aim of this study is to assess the nature, prevalence and correlates of analgesic dependence among patients with acute or chronic spinal pain.

Background

Lack of ability in basic mobility skills is associated with increased mortality in patients with hip fractures. The aim of this study was to identify predictors for performing basic mobility skills at discharge.

Aims

The primary aim of this study was to address the hypothesis that fracture morphology might be more important than posterior malleolar fragment size in rotational type posterior malleolar ankle fractures (PMAFs). The secondary aim was to identify clinically important predictors of outcome for each respective PMAF-type, to challenge the current dogma that surgical decision-making should be based on fragment size.

The aims were: (1) assess the influence of COVID-19 on mortality in hip fracture; (2) identify predictors of COVID-19 status, and (3) investigate whether social lockdown influenced the epidemiology of hip fracture.

A multicentre retrospective study was conducted of all patients presenting to six hospitals with hip fracture over a 46-day period (23 days pre-/post-lockdown). Demographics, residence, place of injury, presentation blood tests, Nottingham Hip Fracture Score, time to surgery, operation, ASA grade, anaesthetic, length of stay, COVID-19 status, and 30-day mortality were recorded.

Of 317 patients with hip fracture 27 (8.5%) had a positive COVID-19 test; only 7 (26%) had symptoms on admission. COVID-19-positive patients had significantly lower 30-day survival compared to those without COVID-19 (67% versus 92%, p<0.001). COVID-19 was independently associated with increased 30-day mortality adjusting for: (1) age, sex, residence (HR 2.93, p=0.008); (2) Nottingham Hip Fracture Score (HR 3.52, p=0.001), and (3) ASA (HR 3.45, p=0.004). Platelet count predicted subsequent COVID-19 status; a value <217 ×109/L was 68% specific and sensitive (95% CI 58 to 77, p=0.002). A similar number of patients presented with hip fracture pre-lockdown (n=160) and post-lockdown (n=157); there was no significant difference in demographics, place of injury, Nottingham Hip Fracture Score, time to surgery, ASA, or management.

COVID-19 was independently associated with an increased 30-day mortality in hip fracture. Most patients with COVID-19 lacked suggestive symptoms at presentation. Platelet count was an indicator of risk of COVID-19 infection. These findings have urgent implications for the delivery of hip fracture services.

Background

Readmission following any total joint arthroplasty has become a closely watched metric for many hospitals in the United States because financial penalties imposed by CMS for excessive readmissions occurring within thirty days of discharge will be forthcoming in 2015. The purpose of this study was to identify both preoperative comorbidities associated with and postoperative reasons for readmission within thirty days following primary total joint arthroplasty in the lower extremity.

The purpose of this study was to examine a cohort of patients with minor acetabular dysplasia features in order to identify the preoperative clinical characteristics and imaging findings that differentiate patients with hip instability from patients with impingement.

A retrospective cohort study of patients with borderline acetabular dysplasia was performed. All patients were identified by prospective radiographic evaluation with an LCEA between 20° and 25°. Multivariate statistical analyses were used to identify independent predictors of disease type.

Of the 143 hips in the cohort, 39.2% (n=56) had the diagnosis of instability, while 60.8% (n=87) had the diagnosis of impingement. The cohort included 109 females (76.2%) and 34 males (23.8%).

Hips with instability had a lower LCEA (21.8° vs. 22.8°; p<0.001), lower ACEA (23.3° vs. 26.6°; p=0.002), a higher AI (11.8° vs. 8.5°; p<0.001), and a lower maximum alpha angle (54.4° vs. 61.1°; p=0.001). The odds of instability increased 1.7 times for each one-degree decrease in LCEA, 1.4 times for each one-degree decrease in ACEA, and 1.1 times for each one-degree increase in acetabular inclination (all p0.003). Female sex was strongly associated with instability.

The instability subgroup had greater range of motion (IRF, 22.7° vs. 12.4°, p<0.001) and total arc of motion (IRF+ERF, 61.2° vs. 47.4°, p<0.001). We identified predictors of diagnosis including: acetabular inclination (1.49, p<0.001), ACEA (0.89, p=0.007), crossover sign (0.27, p=0.014), preoperative mHHS (0.96, p=0.014), IRF (1.10, p=0.001), and age (0.88, p=0.001).

Patients with symptomatic instability tend to have increased acetabular inclination, decreased ACEA, greater functional limitations, younger, greater IRF, while hips with impingement demonstrate the opposite trends.

Introduction

There are several advantages of unicompartmental knee arthroplasty (UKA) in the treatment of isolated compartment osteoarthritis (OA) compared to the conventional total knee arthroplasty. Although various series report similar survivorship results, the national registries tend to show higher revision rates among the UKA. Persisting, unexplainable pain is a leading cause for UKA revision surgery. Therefore it is essential to investigate the various patient specific characteristics which might influence outcome following UKA in order to minimize revision rates and optimize clinical outcomes. The purpose of this study is to evaluate the influence of the various individual patient factors, including pre-operative radiographic parameters, on the outcome following UKA.

Introduction

Intraoperative periprosthetic femoral fractures (IOPFF) lead to reduced implant survival. A deeper understanding of predictors enables surgeons to modify techniques and patient selection to reduce the risk of IOPFF. The aim of this study was to estimate predictors of IOPFF and each anatomical subtype (calcar crack, trochanteric fracture, femoral shaft fracture) during primary THA.

The aim of the study was to describe the failure rate of locking plates used for internal fixation of distal femoral fractures and to identify independent predictors of failure.

A consecutive series of 147 patients presenting to the study unit during an 8 year period with a distal femoral fracture were identified from a prospectively compiled trauma database. There were 117 females and 30 males, with a mean age of 70.7 years (13 to 99 years), of which 77 were periprosthetic fractures and 70 were supracondylar fractures around native knees.

There were 35 failures of fixation. The commonest cause was non-union (n=31). The survival of the plate 2 years post-surgery was 74percnt; (95percnt; CI 64percnt; to 84percnt;), which remained static to a mean follow of 5 years. There was no difference in failure of fixation according to gender (p=0.32) or if there was a periprosthetic fracture (p=0.8). Younger age (61.8 vs. 73.6 years, p=0.004), increasing level of comorbidity (p=0.02), and fracture comminution (p=0.001) were all significant predictors of failure of fixation. Cox regression analysis confirmed younger age (p=0.04), increasing comorbidity (p=0.002), and fracture comminution (p=0.002) as independent predictors of failure of fixation and non-union after adjusting for confounding.

The failure of locking plates for distal femoral fractures occurs in more than one in five patients. The independent predictors could be used to identify those patients at greatest risk of failure of the locking plate, who may benefit from alternative methods of fixation, primary bone grafting, or interventions that may aid union.

We undertook a retrospective cohort study to determine clinical outcomes following the revision of metal-on-metal (MoM) hip replacements for adverse reaction to metal debris (ARMD), and to identify predictors of time to revision and outcomes following revision. Between 1998 and 2012 a total of 64 MoM hips (mean age at revision of 57.8 years; 46 (72%) female; 46 (72%) hip resurfacings and 18 (28%) total hip replacements) were revised for ARMD at one specialist centre. At a mean follow-up of 4.5 years (1.0 to 14.6) from revision for ARMD there were 13 hips (20.3%) with post-operative complications and eight (12.5%) requiring re-revision.

The Kaplan–Meier five-year survival rate for ARMD revision was 87.9% (95% confidence interval 78.9 to 98.0; 19 hips at risk). Excluding re-revisions, the median absolute Oxford hip score (OHS) following ARMD revision using the percentage method (0% best outcome and 100% worst outcome) was 18.8% (interquartile range (IQR) 7.8% to 48.3%), which is equivalent to 39/48 (IQR 24.8/48 to 44.3/48) when using the modified OHS. Histopathological response did not affect time to revision for ARMD (p = 0.334) or the subsequent risk of re-revision (p = 0.879). Similarly, the presence or absence of a contralateral MoM hip bearing did not affect time to revision for ARMD (p = 0.066) or the subsequent risk of re-revision (p = 0.178).

Patients revised to MoM bearings had higher rates of re-revision (five of 16 MoM hips re-revised; p = 0.046), but those not requiring re-revision had good functional results (median absolute OHS 14.6% or 41.0/48). Short-term morbidity following revision for ARMD was comparable with previous reports. Caution should be exercised when choosing bearing surfaces for ARMD revisions.

Cite this article: Bone Joint J 2014;96-B:1600–9.