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. Methods. We developed the Shanghai Prediction Model for Elbow Stiffness Surgical Outcome (SPESSO) based on a dataset of 551 patients who underwent open arthrolysis of the elbow in four institutions. Demographic and clinical characteristics were collected from medical records. The least absolute shrinkage and selection operator regression model was used to optimize the selection of relevant features. Multivariable logistic regression analysis was used to build the SPESSO. Its prediction performance was evaluated using the concordance index (C-index) and a calibration graph. Internal validation was conducted using bootstrapping validation. Results. BMI, the duration of stiffness, the preoperative ROM, the preoperative intensity of pain, and grade of post-traumatic osteoarthritis of the elbow were identified as predictors of outcome and incorporated to construct the nomogram. SPESSO displayed good discrimination with a C-index of 0.73 (95% confidence interval 0.64 to 0.81). A high C-index value of 0.70 could still be reached in the interval validation. The calibration graph showed good agreement between the nomogram prediction and the outcome. Conclusion. The newly developed SPESSO is a valid and convenient model which can be used to predict the outcome of open arthrolysis of the elbow. It could assist clinicians in counselling patients regarding the choice and expectations of treatment. Cite this article: Bone Joint J 2022;104-B(4):486–494

Several different algorithms attempt to estimate life expectancy for patients with metastatic spine disease. The Skeletal Oncology Research Group (SORG) has recently developed a nomogram to estimate survival of patients with metastatic spine disease. Whilst the use of the SORG nomogram has been validated in the international context, there has been no study to date that validates the use of the SORG nomogram in New Zealand. This study aimed to validate the use of the SORG nomogram in Aotearoa New Zealand. We collected data on 100 patients who presented to Waikato Hospital with a diagnosis of spinal metastatic disease. The SORG nomogram gave survival probabilities for each patient at each time point. Receiver Operating Characteristic (ROC) Area Under Curve (AUC) analysis was performed to assess the predictive accuracy of the SORG score. A calibration curve was also performed, and Brier scores calculated. A multivariate Cox regression analysis was performed. The SORG score was correlated with 30 day (AUC = 0.72) and 90-day mortality (AUC = 0.71). The correlation between the SORG score and 90-day mortality was weaker (AUC = 0.69). Using this method, the nomogram was correct for 79 (79%) patients at 30-days, 59 patients (59%) at 90-days, and 42 patients (42%) at 365-days. Calibration curves demonstrated poor forecasting of the SORG nomogram at 30 (Brier score = 0.65) and 365 days (Brier score = 0.33). The calibration curve demonstrated borderline forecasting of the SORG nomogram at 90 days (Brier score = 0.28). Several components of the SORG nomogram were not found to be correlated with mortality. In this New Zealand cohort the SORG nomogram demonstrated only acceptable discrimination at best in predicting life 30-, 90- or 356-day mortality in patients with metastatic spinal disease

Abstract. Introduction. Minimising postoperative complications and mortality in COVID-19 patients who were undergoing trauma and orthopaedic surgeries is an international priority. Aim was to develop a predictive nomogram for 30-day morbidity/mortality of COVID-19 infection in patients who underwent orthopaedic and trauma surgery during the coronavirus pandemic in the UK in 2020 compared to a similar period in 2019. Secondary objective was to compare between patients with positive PCR test and those with negative test. Methods. Retrospective multi-center study including 50 hospitals. Patients with suspicion of SARS-CoV-2 infection who had underwent orthopaedic or trauma surgery for any indication during the 2020 pandemic were enrolled in the study (2525 patients). We analysed cases performed on orthopaedic and trauma operative lists in 2019 for comparison (4417). Multivariable Logistic Regression analysis was performed to assess the possible predictors of a fatal outcome. A nomogram was developed with the possible predictors and total point were calculated. Results. Of the 2525 patients admitted for suspicion of COVID-19, 658 patients had negative preoperative test, 151 with positive test and 1716 with unknown preoperative COVID-19 status. Preoperative COVID-19 status, sex, ASA grade, urgency and indication of surgery, use of torniquet, grade of operating surgeon and some comorbidities were independent risk factors associated with 30-day complications/mortality. The 2020 nomogram model exhibited moderate prediction ability. In contrast, the prediction ability of total points of 2019 nomogram model was excellent. Conclusions. Nomograms can be used by orthopaedic and trauma surgeons as a practical and effective tool in postoperative complications and mortality risk estimation

Background. Two-stage revision is considered the gold standard for treatment of knee prosthetic joint infections. Current guidelines for selecting the most appropriate procedure to eradicate knee prosthetic joint infections are based upon the duration of symptoms, the condition of the implant and soft tissue evaluated during surgery and the infecting organism. A more robust tool to identify candidates for two-stage revision and who are at high risk for treatment failure might improve preoperative risk assessment and increase a surgeon's index of suspicion, resulting in closer monitoring, optimization of risk factors for failure and more aggressive management of those patients who are predicted to fail. Methods. Charts from 3,809 revision total joint arthroplasties were reviewed. Demographic data, clinical data and disease follow-up on 314 patients with infected total knee arthroplasty treated with two-stage revision were collected. Univariate analyses were performed to determine which variables were independently associated with failure of the procedure to eradicate the prosthetic joint infections. Cox regression was used to construct a model predicting the probability of treatment failure and the results were used to generate a nomogram which was internally validated using bootstrapping. Results. 209 (66.6%) cases experienced reinfection at an average of 429 days (range, 9 to 3,886) following the two-stage revision. Univariate analysis identified multiple variables independently associated with reinfection including: a longer duration of symptoms (p<0.001), a longer time from the index total knee arthroplasty (p=0.003), a higher number of previous surgeries in the same joint (p<0.001), an elevated C-reactive protein (p=0.005), an elevated erythrocyte sedimentation rate (p=0.006), a low hemoglobin (p=0.001), a previous infection in the same joint (p<0.001), diabetes (p<0.001), and heart disease (p=0.006). Among 1,000 bootstrap samples, the bias corrected receiver operating characteristic for the nomogram was 0.77. Conclusions. Preoperative knowledge of the probability that a treatment strategy will eradicate a patient's prosthetic joint infection may improve risk assessment and allow adequate time for consideration of alternative therapies

Prediction tools are instruments which are commonly used to estimate the prognosis in oncology and facilitate clinical decision-making in a more personalized manner. Their popularity is shown by the increasing numbers of prediction tools, which have been described in the medical literature. Many of these tools have been shown to be useful in the field of soft-tissue sarcoma of the extremities (eSTS). In this annotation, we aim to provide an overview of the available prediction tools for eSTS, provide an approach for clinicians to evaluate the performance and usefulness of the available tools for their own patients, and discuss their possible applications in the management of patients with an eSTS.

Cite this article: Bone Joint J 2022;104-B(9):1011–1016.

Anteroposterior (AP) radiographs remain the standard of care for pre- and post-operative imaging during total hip arthroplasty (THA), despite known limitation of plain films, including the inability to adequately account for distortion caused by variations in pelvic orientation. Of specific interest to THA surgeons are distortions associated with pelvic tilt, as unaccounted for tilt can significantly alter radiographic measurements of cup position. Several authors have proposed methods for correcting for pelvic tilt on radiographs but none have proven reliable in a THA population. The purpose of our study was to develop a method for correcting pelvic tilt on AP radiographs in patients undergoing primary or revision THA. CT scans from 20 patients/cadaver specimens (10 male, 10 female) were used to create 3D renderings, from which synthetic radiographs of each pelvis were generated (Figure 1). For each pelvis, 13 synthetic radiographs were generated, showing the pelvis at between −30° and 30° of pelvic tilt, in 5° increments. On each image, 8 unique parameters/distances were measured to determine the most appropriate parameters for calculation of pelvic tilt (Figure 2). The most reliable and accurate of these parameters was determined via regression analysis and used to create gender-specific nomograms from which pelvic tilt measurements could be calculated (Figure 3). The accuracy and reliability of the nomograms and correction method were subsequently validated using both synthetic radiographs (n=50) and stereoradiographic images (n=58). Of 8 parameters measured, the vertical distance between the superior margin of the pubic symphysis and the transischial line (PSTI) was determined to be the most reliable (r=−0.96, ICC=0.94). Mean tilt calculated from synthetic radiographs (0.6°±18.6°) correlated very strongly (r=0.96) with mean known tilt (0.5°±17.9°, p=0.98). Mean pelvic tilt calculated from AP EOS images (3.2°±9.9°) correlated strongly (r=0.77) with mean tilt measured from lateral EOS images (3.8°±8.2°, p=0.74). No gender differences were noted in mean tilt measurements in synthetic images (p=0.98) or EOS images (p=0.45). Our method of measuring PSTI and POD on AP images and applying these measurements to nomograms provides a validated and reliable method for estimating the degree of pelvic tilt on AP radiographs during THA. For any figures or tables, please contact authors directly

Topic. Utilizing radiographic, physical exam and history findings, we developed a novel clinical score to aid in the surgical decision making process for hips with borderline/ transitional dysplastic hips. Background. Treatment of borderline acetabular dysplasia (BD) is controversial with some patients having primarily instability-based symptoms while others have impingement-based symptoms. The purpose of this study was to identify the most important patient characteristics influencing the diagnosis of instability vs. non-instability, develop a clinical score (Borderline Hip Instability Score, BHIS) to collectively characterize these factors and to externally validate BHIS in a multicenter cohort BD patients. Methods. First a retrospective cohort of 186 hips undergoing surgical treatment of BD (LCEA 20°-25°) from a single surgeon experienced in arthroscopic and open techniques was used. Multivariate analysis determined characteristics associated with presence of instability (PAO+/−hip arthroscopy) or absence of instability (isolated hip arthroscopy) based on clinical diagnosis. During the study period, 39.8% of the cohort underwent PAO. Multivariate analysis with bootstrapping was performed and results were transformed into a BHIS nomogram (higher score representing more instability). Then, BHIS was externally validated in 114 BD patients enrolled in a multicenter prospective cohort study across 10 surgeons (with varied treatment approaches from arthroscopy to open procedures). Results. The most parsimonious, best fit model included 4 variables associated with the diagnosis of instability: acetabular inclination (AI), anterior center edge angle (ACEA), maximum alpha angle, and internal rotation in 90 degrees of flexion (IRF). Sex and LCEA were not significant predictors. Mean BHIS in the population was 50.0 (instability 57.7 ±7.9; non-instability 44.8±7.3, p<0.001). BHIS demonstrated excellent predictive (discriminatory) ability with c-statistic=0.89. In Part 2, BHIS maintained excellent c-statistic=0.92 in external validation. Mean BHIS in the external cohort was 53.9 (instability 66.5±11.5; non-instability 43.0±10.8, p<0.001). Discussion. In patients with BD, key factors in diagnosing significant instability treated with PAO were AI, ACEA, maximum alpha-angle, and IRF. The BHIS score allowed for differentiation of patients with and without instability in the development and external validation cohort. For any tables or figures, please contact the authors directly

Introduction Bilateral total knee replacement under one anaesthetic is a common procedure. Claimed benefits include: shorter hospital stays, fewer complications of some kinds, lower over all cost and more efficient use of staff time. In general the literature supports these concepts though some writers caution against the procedure. Most studies come from large university hospitals but most joint replacements are done in smaller hospitals. At Calvary Hospital we instituted a quality assessment review of our experience to determine patient safety and cost savings. Methods A medical records review between 1997 and 2001 showed 63 patients had bilateral total knee replacement (126 knees). We further identified 38 patients who had both knees replaced at separate admissions within one year (76 knees), these were the staged knee replacements. We selected a matched subset of the patients who had only one joint replaced in this period (125 knees). A review was carried out over a wide variety of parameters on a relation database. Results The incidence of infection, unplanned return to theatre and DVT was too low for this study to have statistical power and little difference was noted. Amongst the more common post-operative respiratory, cardiovascular and gastrointestinal complications no significant difference was noted per hospital admission. Post-operative confusion was not more common in bilateral replacements and we felt that fat embolism syndrome was not increased. Neither, type of anaesthesia, previous medical history nor post-operative care predicted for confusion but we did note a strikingly increased incidence in patients of low BMI. Contrary to common views obese patients did not have more complications or longer hospital stays. Mobilisation in heavy patients is not prolonged provided they have good upper limb strength. Blood transfusion is more likely in bilateral cases but our review has allowed us to formulate a nomogram based on weight and pre-operative haemoglobin to improve blood management. High admission rates to ICU were noted but mostly for precautionary reasons, the unplanned admission rate was not greater. Pre-operative urinary tract infection and use of an IDC were not associated with any infective events. Conclusions Bilateral total knee replacement was found to be a safe proceedure with complication rates equivalent to single knee replacement. For the patient who has severe arthritis in both knees it is prefered to repeated single knee replacement as the exposure to complications is halved. A nomogram to predict blood transfusion requirements has allowed a reduction in the transfusion rate for all groups. Twenty-three hour recovery admission covers the needs of bilateral replacement patients in the immediate post-opertaive setting. Cost savings are identified allowing four knees to be replaced, if done bilaterally, for each three knees replaced as seperate admissions

Aims

We aimed to develop a gene signature that predicts the occurrence of postmenopausal osteoporosis (PMOP) by studying its genetic mechanism.

Background. The optimal strategy for postoperative deep venous thrombosis (DVT) prophylaxis remains among the most controversial topics in hip and knee arthroplasty. Warfarin, the most commonly used chemical anticoagulant, initially causes transient hypercoagulability; however the optimal timing of treatment with respect to surgery remains unclear. Our purpose was to evaluate the effects of pre- versus postoperative initiation of warfarin therapy with a primary endpoint of perioperative change in hemoglobin (pre- minus post-operative level), with secondary endpoints of postoperative International Normalized Ratio (INR), drain output, and bleeding/thrombotic events. Methods. A quasi-experimental study design was employed, under which patients were assigned to begin taking warfarin the night prior to surgery or the night following surgery based on day of the week seen in clinic. An a priori power analysis was conducted in order to ensure appropriate enrollment to detect a 0.5 g/dL difference in perioperative change in hemoglobin between groups, given an alpha level of 0.05 and beta of 0.80. Based on the results, the study included all primary, elective total hip and knee arthroplasties performed by a single surgeon over a 12 month period. Fifteen patients were excluded (7 chronic anticoagulation, 3 hip fractures, 2 medical contraindications, 3 simultaneous procedures), leaving 165 cases (108 hips, 57 knees) available for study. Of these, 73 received warfarin preoperatively (49 hips, 24 knees) and 92 postoperatively (59 hips, 33 knees). Warfarin was dosed according to a standard nomogram in both groups. INR (on postoperative days 1 and 2), perioperative decrease in hemoglobin (difference between level preoperatively and on postoperative days 1 and 2), and drain outputs were compared between groups using a student t test. Adverse events (transfusions, hematomas, epidural complications, and pulmonary embolus) were compared using two-tailed Fischer's exact test. Results. No statistically significant difference in perioperative hemoglobin change was observed between treatment groups on either postoperative day 1 (mean 3.279 versus 3.377, p=0.6824) or 2 (mean 4.0 versus 4.12, p=0.6831). As expected, the preoperative warfarin group demonstrated higher INRs on both postoperative days 1 (mean 1.18 versus 1.12, p=0.0023) and 2 (mean 1.46 versus 1.31, p=0.0006). Of note, preoperative warfarin dosing was also associated with significantly lower drain outputs (mean 185.4 versus 268.7, p=0.0025). 9 transfusions (4 preoperative dosing, 5 postoperative dosing), 3 hematomas (1 preoperative dosing, 2 postoperative dosing), and 1 pulmonary embolus (preoperative dosing) occurred, but no significant difference could be detected given the numbers available for study. Conclusions. Initiation of warfarin pre- rather than postoperatively was not associated with a significant difference in perioperative hemoglobin change, although a significant reduction in drain output was observed. Larger studies are needed to determine whether the risk of adverse events is increased with either dosing strategy

Objectives: To formulate a scoring system enabling decision making for prophylactic stabilization of the femur following surgical resection of a soft tissue sarcoma (STS) of the thigh. Methods: A logistic regression model was developed using patient variables collected from a prospective database. The test group included 22 patients with radiation-related pathological femur fracture following surgery and radiation for a thigh STS. The control group of 79 patients had similar treatment but without a fracture. No patients received chemotherapy. Mean follow-up was 8.6 years. Variables examined were: Age (< 49, 50–70, > 70 years), gender, tumor size (0–7, 8–14, > 14 cm), radiation dose (low=5000 cGy, high> 6000 cGy), extent of periosteal stripping (< 10, 10–20, > 20 cm) and thigh compartment (posterior, adductor, anterior). A score was assigned to each variable category based on the coefficients obtained in the logistic regression model. Results: Based on the regression model and an optimal cut-point, the ability to predict radiation associated fracture risk was 91% sensitive and 86% specific. The area under the Receiver Operating Characteristic (ROC) curve was 0.9, which supports this model as a very accurate predictor. Conclusions: Radiation-related femur fractures following combined surgery and radiation treatment for STS are uncommon, but are difficult to manage and their non-union rate is extremely high. These results suggest that it is possible to predict radiation-associated pathological fracture risk with high sensitivity and specificity. This would allow identification of high risk patients and treatment with prophylactic IM nail stabilization. Presentation of this model as a clinical nomogram will facilitate its clinical use

Purpose: To formulate a scoring system enabling decision making for prophylactic stabilization of the femur following surgical resection of a soft tissue sarcoma (STS) of the thigh. Method: A logistic regression model was developed using patient variables collected from a prospective database. The test group included 22 patients with radiation-related pathological femur fracture following surgery and radiation for a thigh STS. The control group of 79 patients had similar treatment but without a fracture. No patients received chemotherapy. Mean follow-up was 8.6 years. Variables examined were: Age (70 years), gender, tumor size (0–7, 8–14, > 14 cm), radiation dose (low=5000 cGy, high> 6000 cGy), extent of periosteal stripping (20 cm) and thigh compartment (posterior, adductor, anterior). A score was assigned to each variable category based on the coefficients obtained in the logistic regression model. Results: Based on the regression model and an optimal cut-point, the ability to predict radiation associated fracture risk was 91% sensitive and 86% specific. The area under the Receiver Operating Characteristic (ROC) curve was 0.9, which supports this model as a very accurate predictor. Conclusion: Radiation-related femur fractures following combined surgery and radiation treatment for STS are uncommon, but are difficult to manage and their non-union rate is extremely high. These results suggest that it is possible to predict radiation-associated pathological fracture risk with high sensitivity and specificity. This would allow identification of high risk patients and treatment with prophylactic IM nail stabilization. Presentation of this model as a clinical nomogram will facilitate its clinical use

There has been debate in the literature over the years regarding whether. rib resection, and. surgical approach have a significant impact on long term respiratory function following corrective surgery in idiopathic scoliosis patients. We undertook a minimum 10 year review of prospective data in patients who had undergone corrective surgery for idiopathic scoliosis. Patients had pre-operative, two year (where available) and 10 year follow-up respiratory function tests performed. Variables noted were sex, age at surgery, surgical approach, rib release (simple rib osteotomy, not resection), and percentage correction of curvature. All absolute respiratory function values were converted to percentages relative to a normal population of the same height, sex and age with reference to both arm span and height nomograms thus avoiding the need for a control group. Using accepted statistical norms and appropriate analysis we would be able to confirm a 10% difference in respiratory function. A literature review was also undertaken as part of this study. The only statistically significant change in respiratory function was a drop in FVC at 10 years in patients in whom a posterior approach had been used for correction without a rib release. In no other group (by other approach, sex, age, initial curvature, or curvature correction) was there a significant difference in long term respiratory function. In our study the surgical approach did not have a significant impact on long term respiratory function. Rib release is a safe procedure to undertake as part of scoliosis correction

Materials and Methods: The institution’s prospective database of unicompartmental knee replacements was reviewed for all Oxford Phase III Unicompartmental Knee Replacement (Biomet, UK) undertaken from January 2004 to July 2007. This identified a total of 645 procedures undertaken. We included all cases where there was pre-operative skyline radiographs and American Knee Scores, Oxford Knee Score and SF-12 data, in addition to skyline radiographs, OKS and SF-12 data with a minimum of 2 years follow-up. All patients without this baseline and follow-up data were excluded. This provided a total of 196 knees (162 patients). Using Altman’s nomogram, the sample size was calculated to be 85 for a power of 90%, with an α significance level of 0.05. Using this database, digital radiographs were assessed using the institution’s PACS system. Pre-operative and follow-up skyline radiographs following Jones et al’s (1993) patellofemoral scoring system were examined by four assessors utilising Jones’ patellofemoral scoring system. In addition, in cases where patellofemoral joint changes were evident, each assessor acknowledged whether this involved the medial, lateral or bilateral aspects of the patellofemoral joint. Intra-observer reliability was made comparing the four assessors. Statistical analysis was performed, using the Statistical Package for the Social Sciences (SPSS) 16.0 for Windows (SPSS Inc, Chicago, Illinois). In order to determine whether changes in patellofemoral joint status related to patients function or quality of life, the difference in OKS and SF-12 from pre-operative to the follow-up period was assessed. Results: There was a statistically significant progression of patellofemoral osteoarthritis as found on the preoperative and postoperative radiographs (p< 0.01, Mann Whitney), there was a correlation between a low OKS and Jones patellofemoral score (P< 0.05, Mann-Whitney). However, there was no correlation between the site of patellofemoral involvement and outcome scores. Conclusion: Due consideration should be taken when offering medial unicompartmental knee replacement to patients with patellofemoral involvement and this is independent of the site of patellofemoral involvement

Aims

The diagnosis of periprosthetic joint infection (PJI) has always been challenging. Recently, D-dimer has become a promising biomarker in diagnosing PJI. However, there is controversy regarding its diagnostic value. We aim to investigate the diagnostic value of D-dimer in comparison to ESR and CRP.

The October 2015 Oncology Roundup³⁶⁰ looks at: Radiotherapy for the radioresistant; Multiple hereditary exostosis; The total femur as a limb salvage option; Survival prediction in osteosarcoma; What happens when chondrosarcoma recurs?; Thumbs up for vascularised fibular graft; Radiotherapy and survival; Musculoskeletal tumours in pregnancy

The December 2015 Oncology Roundup³⁶⁰ looks at: Amputation may not be the best option; Growing golf balls bad news!; How close is safe? Radiotherapy and surgery; Lymphocyte: monocyte ratio in osteosarcoma; Are borderline cartilage tumours really borderline?; Boosting algorithms improves survival estimates; CT better than Mirels?