Scaphoid kinematics in scapholunate instability: a dynamic CT study.

OBJECTIVE: The scaphoid is proposed to be driven by the distal carpal row in scapholunate instability (SLI) as it is dissociated from the proximal row. The aim of this study was to describe the 6 degrees of freedom kinematics of the scaphoid using dynamic CT in the normal and SLI wrists. We hypothesised that the SLI scaphoid would demonstrate kinematic evidence conforming to distal row motion. MATERIALS AND METHODS: We studied dynamic CT scans of 17 SLI and 17 normal wrists during ulnar to radial deviation and extension to flexion. The radio-scaphoid angles in three anatomic planes were calculated in the wrist neutral position and during wrist motion. The centroid position was also calculated in the wrist neutral position and during wrist motion. The scapho-capitate motion index (SCI) was calculated as a ratio between the scaphoid and the capitate motion. RESULTS: In the neutral position of the wrist, the SLI scaphoid was flexed, internally rotated, and radially translated compared to the normal scaphoid. During wrist motion, the SLI scaphoid had more 'in-plane' motion and less 'out-of-plane' motion with a higher SCI during wrist neutral to radial deviation and extension to neutral. CONCLUSION: We have described the malalignment of the SLI scaphoid in the neutral position of the wrist and 6 degrees of freedom kinematics during wrist motion of the SLI scaphoid compared to the normal. The SLI scaphoid conformed more to the distal row motion than the normal scaphoid. This information may help define the surgical reconstruction techniques for SLI.

Use of Multiprognostic Index Domain Scores, Clinical Data, and Machine Learning to Improve 12-Month Mortality Risk Prediction in Older Hospitalized Patients: Prospective Cohort Study.

BACKGROUND: The Multidimensional Prognostic Index (MPI) is an aggregate, comprehensive, geriatric assessment scoring system derived from eight domains that predict adverse outcomes, including 12-month mortality. However, the prediction accuracy of using the three MPI categories (mild, moderate, and severe risk) was relatively poor in a study of older hospitalized Australian patients. Prediction modeling using the component domains of the MPI together with additional clinical features and machine learning (ML) algorithms might improve prediction accuracy. OBJECTIVE: This study aims to assess whether the accuracy of prediction for 12-month mortality using logistic regression with maximum likelihood estimation (LR-MLE) with the 3-category MPI together with age and gender (feature set 1) can be improved with the addition of 10 clinical features (sodium, hemoglobin, albumin, creatinine, urea, urea-to-creatinine ratio, estimated glomerular filtration rate, C-reactive protein, BMI, and anticholinergic risk score; feature set 2) and the replacement of the 3-category MPI in feature sets 1 and 2 with the eight separate MPI domains (feature sets 3 and 4, respectively), and to assess the prediction accuracy of the ML algorithms using the same feature sets. METHODS: MPI and clinical features were collected from patients aged 65 years and above who were admitted to either the general medical or acute care of the elderly wards of a South Australian hospital between September 2015 and February 2017. The diagnostic accuracy of LR-MLE was assessed together with nine ML algorithms: decision trees, random forests, extreme gradient boosting (XGBoost), support-vector machines, naïve Bayes, K-nearest neighbors, ridge regression, logistic regression without regularization, and neural networks. A 70:30 training set:test set split of the data and a grid search of hyper-parameters with 10-fold cross-validation-was used during model training. The area under the curve was used as the primary measure of accuracy. RESULTS: A total of 737 patients (female: 370/737, 50.2%; male: 367/737, 49.8%) with a median age of 80 (IQR 72-86) years had complete MPI data recorded on admission and had completed the 12-month follow-up. The area under the receiver operating curve for LR-MLE was 0.632, 0.688, 0.738, and 0.757 for feature sets 1 to 4, respectively. The best overall accuracy for the nine ML algorithms was obtained using the XGBoost algorithm (0.635, 0.706, 0.756, and 0.757 for feature sets 1 to 4, respectively). CONCLUSIONS: The use of MPI domains with LR-MLE considerably improved the prediction accuracy compared with that obtained using the traditional 3-category MPI. The XGBoost ML algorithm slightly improved accuracy compared with LR-MLE, and adding clinical data improved accuracy. These results build on previous work on the MPI and suggest that implementing risk scores based on MPI domains and clinical data by using ML prediction models can support clinical decision-making with respect to risk stratification for the follow-up care of older hospitalized patients.

Radiocarpal and midcarpal kinematics in scapholunate instability: a four-dimensional CT study in vivo.

The distribution of motion between the radiocarpal and midcarpal joints in scapholunate instability is poorly understood. This has potential implications in predicting degenerative changes and in selecting salvage procedures. We studied 19 healthy wrists and 19 wrists with scapholunate instability using dynamic computed tomography during wrist extension to flexion and ulnar to radial deviation. Radiocarpal and midcarpal kinematics of the scaphoid and the lunate were computed. In scapholunate instability, in the radial column, there was increased motion in the radiocarpal joint when the wrist was radially deviating beyond 10° or moving from 70° to 40° extension. In both groups, the capitolunate joint was the dominant articulation in the central column. In scapholunate instability, there was significantly more capitolunate motion during 70° to 30° extension. These changes may predict the development of radioscaphoid arthritis and enable identifying a kinematically abnormal wrist. The motion distribution in scapholunate instability was abnormal beyond 10° of radial deviation and between 70° and 40° of wrist extension.Level of evidence: III.

The Clinical Impact of Hospital-Acquired Adverse Drug Reactions in Older Adults: An Australian Cohort Study.

INTRODUCTION: Hospital-acquired adverse drug reactions (HA-ADRs) are common in older adults. However, there is limited knowledge regarding the association between HA-ADRs and adverse clinical outcomes. OBJECTIVE: To investigate the incidence and characteristics of HA-ADRs in older adults, and any association with mortality, length of stay, and readmissions. DESIGN: Prospective cohort study. SETTING AND PARTICIPANTS: Flinders Medical Centre, a large tertiary referral hospital in Adelaide, South Australia. Older adults admitted under the General Medicine and Acute Care of the Elderly units with no previous diagnosis of dementia. METHODS: All patients had a Multidimensional Prognostic Index (MPI) assessment performed within 3 days of the admission. Data collected included age, gender, estimated glomerular filtration rate (eGFR), length of stay, readmissions, and mortality. HA-ADRs were identified by review of individual discharge summaries. Univariate and multivariate analyses were performed to investigate associations with clinical outcomes including mortality, length of stay, and readmissions. Exploratory analyses were performed for HA-ADR groups based on Medical Dictionary for Regulatory Activities System Organ Class and World Health Organization Anatomical Therapeutic Chemical classifications that accounted for ≥10% of all HA-ADRs. RESULTS: There were 737 patients in the cohort with 72 having experienced a HA-ADRs (incidence = 9.8%). Patients with an HA-ADR had increased length of stay and 30-day readmissions compared with those without an HA-ADR. In multivariate analysis, the number of HA-ADRs was associated with in-hospital mortality and length of stay but not post-discharge mortality or readmissions within 30 days. In exploratory analyses, patients with an HA-ADR to antibacterial drugs had significantly higher rates of in-hospital mortality compared with those without these reactions. CONCLUSIONS AND IMPLICATIONS: The number of HA-ADRs are associated with in-hospital mortality and length of stay in older Australian inpatients. The occurrence of HA-ADRs may be a trigger to offer advice to prescribers to prevent future ADRs to similar agents and proactively manage disease to improve health outcomes.

Four-dimensional computed tomography scan for dynamic elbow disorders: recommendations for clinical utility.

BACKGROUND: Four-dimensional computed tomography (4D CT) is rapidly emerging as a diagnostic tool for the investigation of dynamic upper limb disorders. Dynamic elbow pathologies are challenging to diagnose, and at present, limitations exist in current imaging modalities. OBJECTIVE: We aimed to assess the clinical utility of 4D CT in detecting potential dynamic elbow disorders. METHODS: Twenty-eight elbow joints from 26 patients with symptoms of dynamic elbow pathology were included in this study. They were first assessed by a senior orthopedic surgeon with subsequent qualitative data obtained via a Siemens Force Dual Source CT scanner (Erlangen, Germany), producing two- and three-dimensional "static" images and 4D dynamic "movie" images for assessment in each clinical scenario. Clinical assessment before and after scan was compared. RESULTS: Use of 4D CT scan resulted in a change of diagnosis in 16 cases (57.14%). This included a change in primary diagnosis in 2 cases (7.14%) and secondary diagnosis in 14 cases (50%). In 25 cases (89.29%), the 4D CT scan allowed us to understand the pathological anatomy in greater detail which led to a change in the management plan of 15 cases (53.57%). CONCLUSION: 4D CT is a promising diagnostic tool in the management of dynamic elbow disorders and may be considered in clinical practice. Future studies need to compare it with other diagnostic modalities such as three-dimensional CT.

The influence of fracture location and comminution on acute scaphoid fracture displacement: three-dimensional CT analysis.

We aimed to assess the influence of fracture location and comminution on acute scaphoid fracture displacement using three-dimensional CT. CT scans of 51 adults with an acute scaphoid fracture were included. Three-dimensional CT was used to assess fracture location, comminution and displacement. Fracture location was expressed as the height of the cortical breach on the volar and dorsal side of the scaphoid relative to total scaphoid length (%), corresponding to the fracture's entry and exit point, respectively. We found a near-linear relation between dorsal fracture location and displacement. As dorsal fracture location became more distal, translation (ulnar, proximal, volar) and angulation (flexion, pronation) of the distal fragment relative to the proximal fragment increased. Comminuted fractures had more displacement. Dorsal fracture location predictably dictates the direction of translation and angulation in displaced scaphoid fractures. Surgeon attention to dorsal fracture location can help identify displacement patterns and provide guidance in adequately reducing a displaced scaphoid fracture.Level of evidence: III.

Complications After Distal Biceps Tendon Repair: A Systematic Review.

BACKGROUND: Distal biceps tendon injuries typically occur in the dominant arm of men in their fourth decade of life. Surgical repair restores flexion and supination strength, resulting in good functional outcome. The complication profile of each surgical approach and fixation technique has not been widely studied in the literature. PURPOSE: To report the rate of complications after repair of complete distal biceps ruptures, to classify them according to surgical approach and fixation technique, and to analyze risk factors and outcomes of the individual complications. STUDY DESIGN: Systematic review. METHODS: Studies published in English on primary repair of the distal biceps between January 1998 and January 2019 were identified. Data on complications were extracted and classified as major and minor for analysis. A quantitative synthesis of data was done to compare the complication rates between (1) limited anterior incision, extensile anterior incision, and double incision and (2) 4 fixation methods. RESULTS: Seventy-two articles including 3091 primary distal biceps repairs were identified. The overall complication rate was 25% (n = 774). The major complication rate was 4.6% (n = 144) and included a 1.6% (n = 51) rate of posterior interosseous nerve injury; 0.3% (n = 10), median nerve injury; 1.4% (n = 43), rerupture; and a 0.1% (n = 4), synostosis. Brachial artery injury, ulnar nerve injury, compartment syndrome, proximal radius fracture, and chronic regional pain syndrome occurred at a rate of <0.1% each. The majority of nerve injuries resolved with an expectant approach. The minor complication rate was 20.4% (n = 630). The most common complication was lateral cutaneous nerve injury (9.2%, n = 283). An extensile single incision was associated with a higher rate of superficial radial nerve injury when compared to limited single incision(6% vs 2.1%, P = .002). Limited anterior single incision technique had a higher rate of lateral antebrachial cutaneous nerve injury compared to extensile single incision. (9.7% vs 5.2%, P = .03). Synostosis occurred only with double incision. Fixation technique had no significant effect on rerupture rate and posterior interosseous nerve injury rate. CONCLUSION: This is the largest analysis of complications after distal biceps repair, indicating a major complication rate of 4.6%. This study provides valuable data with regard to the choice of technique, surgical approach, and rate of complications, which is essential for surgical planning and patient consent. REGISTRATION: CRD42017074066 (PROSPERO).

Validation and Adaptation of the Multidimensional Prognostic Index in an Older Australian Cohort.

BACKGROUND AND AIMS: The Multidimensional Prognostic Index (MPI), an objective and quantifiable tool based on the Comprehensive Geriatric Assessment, has been shown to predict adverse outcomes in European cohorts. We conducted a validation study of the original MPI, and of adapted versions that accounted for the use of specific drugs and cultural diversity in the assessment of cognition, in older Australians. METHODS: The capacity of the MPI to predict 12-month mortality was assessed in 697 patients (median age: 80 years; interquartile range: 72-86) admitted to a metropolitan teaching hospital between September 2015 and February 2017. RESULTS: In simple logistic regression analysis, the MPI was associated with 12-month mortality (Low risk: OR reference group; moderate risk: OR 2.50, 95% CI: 1.67-3.75; high risk: OR 4.24, 95% CI: 2.28-7.88). The area under the receiver operating characteristic curve (AUC) for the unadjusted MPI was 0.61 (0.57-0.65) and 0.64 (95% CI: 0.59-0.68) with age and sex adjusted. The adapted versions of the MPI did not significantly change the AUC of the original MPI. CONCLUSION: The original and adapted MPI were strongly associated with 12-month mortality in an Australian cohort. However, the discriminatory performance was lower than that reported in European studies.