Plating Versus Intramedullary Nailing of OTA/AO 43C1 and C2 Intra-articular Distal Tibia Fractures: A Propensity Score and Multivariate Analysis.

OBJECTIVE: To compare rates of reduction loss, nonunion, and infection in intra-articular distal tibia fractures (IADTF) treated with limited open reduction internal fixation and intramedullary nailing (IMN) as compared to open reduction internal fixation with plate and screws (plate fixation [PF]). DESIGN: Retrospective review. SETTING: Level-I academic trauma center. PATIENT SELECTION CRITERIA: Patients age ≥ 18 with OTA/AO 43C1 and C2 IADTF treated with IMN or PF between 2013-2021. OUTCOME MEASURES AND COMPARISONS: Loss of reduction, surgical site infection (SSI), nonunion, and patient-reported outcomes (PROs) were compared for IMN versus PF treatments. RESULTS: One hundred ten patients met the inclusion criteria (IMN 33 and PF 77). There was no loss of reduction found. Seventeen nonunions (15% overall; IMN 4/33 and PF 13/77) and 13 SSIs (12% overall; IMN 2/33 and PF11/77) were identified. Despite several risk factors being identified for nonunion and SSI in bivariate analysis, only open fracture remained significant as a risk factor for both nonunion (odds ratio 0.09 for closed fracture, 95% confidence interval, 0.02-0.56, P = 0.009) and SSI (odds ratio 0.07 for closed fracture, 95% confidence interval, 0.06-0.26, P = 0.012) in the multivariate model. Propensity scoring based on presurgical variables was significantly different between patients who received IMN versus PF ( P = 0.03); however, logistic regression incorporating the propensity score revealed no significant association with nonunion and SSI. Adjusting for the propensity score, there remained no association comparing IMN versus PF with nonunion and SSI ( P = 0.54 and P = 0.17, respectively). There was also no difference in PROs between IMN and PF (physical function: P = 0.25 and pain interference: P = 0.21). CONCLUSIONS: Overall nonunion and SSI prevalence was 15% and 12%, respectively, in operatively treated OTA/AO 43C1 and C2 IADTF. An open fracture was a significant risk factor for nonunion and SSI. Metaphyseal fixation through IMN or PF did not affect loss of reduction, nonunion, SSI, or PROs. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Benefiting from trial spacing without the cost of prolonged training: Frequency, not duration, of trials with absent stimuli enhances perceived contingency.

The statistical relation between two events influences the perception of how one event relates to the presence or absence of another. Interestingly, the simultaneous absence of both events, just like their mutual occurrence, is relevant for describing their contingency. In three experiments, we explored the relevance of coabsent events by varying the duration and frequency of trials without stimuli. We used a rapid trial streaming procedure and found that the perceived association between events is enhanced with increasing frequency of coabsent events, unlike the duration of coabsent events, which had little effect. These findings suggest ways in which the benefits of trial spacing, during which both events are absent, could be obtained without increasing total training time. Centrally, this can be done by frequent repeating of shortened coabsent events, each marked by a trial contextual cue. We discuss four potential accounts of how coabsent experience might be processed contributing to this effect: (a) contingency sensitivity, (b) testing effect, (c) reduced associative interference by the context, and (d) reduced encoding interference. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

More frequent, shorter trials enhance acquisition in a training session: There is a free lunch!

The strength of the learned relation between two events, a model for causal perception, has been found to depend on their overall statistical relation, and might be expected to be related to both training trial frequency and trial duration. We report five experiments using a rapid-trial streaming procedure containing Event 1-Event 2 pairings (A trials), Event 1-alone (B trials), Event 2-alone (C trials), and neither event (D trials), in which trial frequencies and durations were independently varied. Judgements of association increased with increasing frequencies of A trials and decreased with increasing frequencies of both B and C trials but showed little effect of frequency of D trials. Across five experiments, a weak but often significant effect of trial duration was also detected, which was always in the same direction as trial frequency. Thus, both frequency and duration of trials influenced learning, but frequency had decidedly stronger effects. Importantly, the benefit of more trials greatly outweighed the observed reduction in effect size caused by a proportional decrease in trial duration. In experiment 5, more trials of proportionately shorter duration enhanced effects on contingency judgments despite a shortening of the training session. We consider the observed 'frequency advantage' with respect to both frequentist models of learning and models based on information. (PsycInfo Database Record (c) 2022 APA, all rights reserved).