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AbstractThis experiment examined single‐process and dual‐process accounts of the development of visual recognition memory. The participants, 6–7‐year‐olds, 9–10‐year‐olds and adults, were presented with a list of pictures which they encoded under shallow or deep conditions. They then made recognition and confidence judgments about a list containing old and new items. We replicated the main trends reported by Ghetti and Angelini () in that recognition hit rates increased from 6 to 9 years of age, with larger age changes following deep than shallow encoding. Formal versions of the dual‐process high threshold signal detection model and several single‐process models (equal variance signal detection, unequal variance signal detection, mixture signal detection) were fit to the developmental data. The unequal variance and mixture signal detection models gave a better account of the data than either of the other models. A state‐trace analysis found evidence for only one underlying memory process across the age range tested. These results suggest that single‐process memory models based on memory strength are a viable alternative to dual‐process models for explaining memory development.

PURPOSE: To report mid-term outcomes of active-duty patients younger than the age of 35 years with shoulder type II SLAP lesions following our technique for double-pulley SLAP repair (DPSR). METHODS: All consecutive patients aged 18 to 35 years from January 2014 through December 2015 who underwent primary DPSR by the senior surgeon with complete outcome scores were identified. The clinical significance measures (patient acceptable symptomatic state [PASS], substantial clinical benefit [SCB], minimal clinically important difference [MCID]) have not yet been fully defined for type II SLAP repair procedures, so the values for biceps tenodesis were used as a stand-in. Patients were excluded if they were lost to follow-up of if they underwent a concomitant rotator cuff repair. Outcome measures were completed by patients within 1 week before surgery and at latest follow-up. RESULTS: Overall, 22 of 41 (53.7%) patients met the inclusion criteria for the study, and all were active-duty military at time of surgery. In total, 21 of 22 (95.5%) patients met the PASS, whereas 20 of 22 (90.9%) achieved SCB and 22 of 22 (100.0%) exceeded the MCID for their operative shoulder as determined by the American Shoulder and Elbow Surgeons score. In total, 19 of 22 (86.4%) patients met the PASS, whereas 22 of 22 (100.0%) achieved SCB and exceeded the MCID for their operative shoulder as determined by the Single Assessment Numeric Evaluation. In addition, 21 of 22 (95.5%) met the PASS, whereas 22 of 22 (100%) achieved SCB and exceeded the MCID for their operative shoulder as determined by the pain visual analog scale. Pre- and postoperative range of motion did not vary significantly. In total, 18 of 22 (81.8%) of patients remained on active duty and were able to return to preinjury work and recreation activity levels. In 2 patients (9.09%), the repair did not heal. CONCLUSIONS: Mid-term outcomes in this population of young, active-duty patients undergoing DPSR for type II SLAP tears demonstrate a statistically and clinically significant ...

Since the civil war, combat sustained peripheral nerve injuries (CSPNI) have been documented during wartime. Warfare has evolved and current combat involves a greater severity of blast injuries secondary to increased use of improvised explosive devices. The purpose of this study was to describe CSPNI and report outcomes after evaluation and treatment. We hypothesize that a shorter time to evaluation will improve outcomes. METHODS: A database including all active duty service members who sustained a CSPNI and were treated by the PNC between 2004 and 2009 was used. Service member demographic information, injury mechanism, CSPNI description, and Medical Research Council (MRC) final motor and sensory outcomes were queried from this database. RESULTS: One hundred and four military service members sustained 144 PNIs. The average age was 26.7 years, and nearly all were men (98.1%). There was no correlation between Sunderland classification and age, specific PNI, injury type, or time to evaluation. Higher Sunderland classifications were found to be correlated with worse final motor (r = 0.51, P < 0.001) and final sensory (r = 0.41, P < 0.001) scores. Final motor and sensory scores were not associated with specific nerve injury, mechanism of injury, initial EMG, or surgical procedure. Shorter time to initial assessment was associated with improved final motor and sensory scores, but was not found to be statistically significant. CONCLUSIONS: As the complexity of CSPNIs progress as combat weaponry evolves, a firm understanding of treatment factors is important. Our study demonstrates in recent conflict that military service members' initial injury severity is a key factor in expected outcome.

BACKGROUND: Superior labrum from anterior to posterior (SLAP) lesions represent a significant cause of shoulder pain and disability among active duty members of the US military. However, few data exist regarding the surgical management of type VIII SLAP lesions. HYPOTHESIS: We hypothesized that arthroscopic repair would decrease pain and increase function at the midterm follow-up and allow for a high rate of maintenance of active duty status. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Consecutive active duty military patients were identified from January 2011 through June 2015 who underwent arthroscopic repair of type VIII SLAP lesions performed by a single surgeon. Patients were excluded if they underwent glenoid microfracture, other capsulolabral repair, or rotator cuff repair. Outcome measures were completed by patients within 1 week before surgery and at latest follow-up: pain visual analog scale, Single Assessment Numeric Evaluation, American Shoulder and Elbow Surgeons shoulder score, and Rowe instability score. RESULTS: A total of 30 patients met the inclusion criteria for the study. The mean ± SD follow-up was 96.60 ± 10.91 months. At final follow-up, the mean visual analog scale score improved from 8.17 ± 1.6 to 1.63 ± 1.90 (P < .0001), the Single Assessment Numeric Evaluation score from 41.65 ± 16.78 to 87.63 ± 13.02 (P < .0001), the American Shoulder and Elbow Surgeons score from 36.47 ± 10.26 to 88.07 ± 13.94 (P < .0001), and the Rowe score from 35.33 ± 6.56 to 90.00 ± 14.68 (P < .0001). Three patients reported postoperative complications, and 1 progressed to further surgery. Overall, 90% of patients remained on active duty military service and were able to return to preinjury levels of work and recreational activity. The failure rate, defined as persistent instability or activity-limiting pain, was 10%. CONCLUSION: The results of this study demonstrated favorable outcomes for the majority of patients after arthroscopic repair of type VIII SLAP lesions at midterm follow-up, ...

Background: Radial head and neck fractures are the most common elbow fracture in the general adult population; however, the optimal treatment for radial head fractures remains a topic of ongoing clinical controversy. The purpose of this study was to determine the rate of return to function, complications, and reoperation following operative management of unstable radial head fractures in a young, active patient population with intense upper extremity demands. Methods: A military health care database was queried for all US military servicemembers undergoing open reduction with internal fixation (ORIF; Current Procedural Terminology [CPT] code: 24665) and radial head arthroplasty (RHA; CPT code: 24666) between 2010 and 2015. All patients with minimum 2-year follow-up were included. Univariate and chi-square analyses were performed to evaluate the association between potential risk factors and the primary outcome measures. Results: A total of 67 ORIF (n = 69 elbows) and 10 RHA patients were included. The average age was 31 ± 8.0 years. At mean follow-up of 3.5 ± 1.1 years, 90% of patients overall were able to return to active military service, 96% of which with unrestricted upper extremity function. Nearly one-third (31.2%) of patients developed at least 1 postoperative complication. RHA has higher overall complication rates (70% vs 48%) when compared with ORIF, but this finding did not reach statistical significance (P = .073). However, RHA had significantly higher rates of implant failure (20% vs 2.9%, P = .0498). Seventeen (21%) individuals required reoperation, 5 of which (6.3%) were revision procedures. Dislocation, coronoid fracture, and concomitant ligamentous repair portended a significantly increased risk of sustaining 1 or more complications (P < .05), while dislocation and requirement for ligamentous repair independently predicted revision surgery (P < .05). Conclusions: Arthroplasty and ORIF are both viable options for treating unstable radial head fractures in a young, athletic population, ...

Background: The objective of this study was to examine the subjective and objective midterm functional clinical outcomes of surgically repaired triceps injuries in a moderate- to high-demand population. Methods: The US Military Health System was queried to identify all surgically treated triceps tendon ruptures between 2008 and 2013. Primary endpoints included rates of rerupture, perioperative complications, or significant persistent elbow dysfunction; Disability of the Arm, Shoulder and Hand (DASH) score, Mayo Elbow score, and ability to do push-ups were also extracted. Results: Thirty-seven patients underwent triceps tendon repair with a mean follow-up of 49.8 ± 17.3 months (range: 26.8-80.2). The most common mechanisms of injury were military duties (27%), sporting activity (24%), or fall-related (21.6%), with most injuries occurring during an eccentric movement (54%). While 45% experienced occasional elbow pain postoperatively, only 1 patient (2.7%) had a rerupture. Despite this, at 2 years, 31 patients (84%) were able to return to full military duty. While 6 patients were discharged from military service, only 1 underwent medical separation while 5 retired for reasons unrelated to their triceps tendon rupture. Patient-reported outcomes were available for 14 patients at final follow-up. The average DASH and Mayo Elbow scores were 4.7 (SD ± 4.7, range: 0-15.9) and 85.4 (SD ± 11.7, range: 60-100), respectively. The cohort could perform mean 54.2 (range: 9-90) push-ups. In additional, 12 of 14 (85.7%) were satisfied with their elbow function. Conclusions: The active duty cohort experienced excellent postoperative results with a high rate of return to military duty, despite nearly half of the patients recognizing some degree of activity-related, elbow pain.

Background Perilunate dislocations and perilunate fracture dislocations (PLDs/PLFDs) are rare and often associated with poor outcomes. Heretofore, these outcomes have not been evaluated in a high-demand military population.

BACKGROUND: Multipotent progenitor cells have been harvested from different human tissues, including the bone marrow, adipose tissue, and umbilical cord blood. Previously, we identified a population of mesenchymal progenitor cells (MPCs) isolated from the traumatized muscle of patients undergoing reconstructive surgery following a war-related blast injury. These cells demonstrated the ability to differentiate into multiple mesenchymal lineages. While distal radius fractures from a civilian setting have a much lower injury mechanism (low-energy trauma), we hypothesized that debrided traumatized muscle near the fracture site would contain multipotent progenitor cells with the ability to differentiate and regenerate the injured tissue. METHODS: The traumatized muscle was debrided from the pronator quadratus in patients undergoing open reduction and internal fixation for a distal radius fracture at the Walter Reed National Military Medical Center. Using a previously described protocol for the isolation of MPCs from war-related extremity injuries, cells were harvested from the low-energy traumatized muscle samples and expanded in culture. Isolated cells were characterized by flow cytometry and q-RT-PCRs and induced to adipogenic, osteogenic, and chondrogenic differentiation. Downstream analyses consisted of lineage-specific staining and q-RT-PCR. RESULTS: Cells isolated from low-energy traumatized muscle samples were CD73+, CD90+, and CD105+ that are the characteristic of adult human mesenchymal stem cells. These cells expressed high levels of the stem cell markers OCT4 and NANOG 1-day after isolation, which was dramatically reduced over-time in monolayer culture. Following induction, lineage-specific markers were demonstrated by each specific staining and confirmed by gene expression analysis, demonstrating the ability of these cells to differentiate into adipogenic, osteogenic, and chondrogenic lineages. CONCLUSIONS: Adult multipotent progenitor cells are an essential component for the success of regenerative ...