Youth Pitcher Fatigue: Medial Elbow Laxity, Ultrasonographic Assessment of Flexor-Pronator Mass Energy Depletion, and Association With Pitch Count.

Background: Ulnar collateral ligament (UCL) injuries in youth pitchers continue to be concerning despite the institution of pitch count limits. Flexor-pronator mass fatigue can lead to diminished dynamic stability, resulting in greater stress on the UCL.

Purpose/hypothesis: To evaluate fatigue of the flexor-pronator mass by assessing changes in medial elbow laxity; noninvasively characterizing alterations in muscle glycogen; and identifying changes in subjective fatigue, strength, range of motion (ROM), pitching velocity, and accuracy with increasing pitches thrown by youth pitchers to their recommended 75-pitch count limit.

Post-operative urinary retention after lower extremity arthroplasty and the peri-operative role of selective alpha-1 adrenergic blocking agents in adult male patients: a propensity-matched retrospective cohort study.

Purpose: The purpose of this study was to determine whether male patients taking pre-operative selective alpha-1 adrenergic blocking agents have a lower likelihood of developing post-operative urinary retention (POUR) and a shorter length of hospitalization following lower extremity arthroplasty.

Methods: A retrospective cohort study was conducted of patients who underwent primary or revision total hip or knee arthroplasty, or unicompartmental knee arthroplasty at an academic institution from January 2002 to May 2014. A cohort of male patients aged 35 and older who were taking a selective alpha-1 blocker prior to surgery (N = 229) were compared with a control group (N = 330) not taking one of these medications.

The AAHKS Clinical Research Award: Prophylactic Tamsulosin Does Not Reduce the Risk of Urinary Retention Following Lower Extremity Arthroplasty: A Double-Blinded Randomized Controlled Trial.

Background: Postoperative urinary retention (POUR) is common. Selective alpha-1 adrenergic antagonists, such as tamsulosin, are effective for treating urinary retention. The purpose of this study is to determine whether perioperative prophylactic tamsulosin reduces the incidence of POUR following total hip and knee arthroplasty.

Reduced Myogenic and Increased Adipogenic Differentiation Capacity of Rotator Cuff Muscle Stem Cells.

Background: Fat accumulation commonly occurs in chronically torn rotator cuff muscles, and increased fat within the rotator cuff is correlated with poor clinical outcomes. The extent of lipid deposition is particularly pronounced in injured rotator cuff muscles compared with other commonly injured muscles such as the gastrocnemius. Satellite cells, which are a tissue-resident muscle stem-cell population, can differentiate into fat cells.

Varied anatomy of the thumb pulley system: implications for successful trigger thumb release.

Purpose: The anatomical arrangement of the thumb pulley system continues to be revised through ongoing investigative research, changing our previous assumptions. This study demonstrates the components and anatomical features of this pulley system in an effort to improve surgical outcomes and to clarify current misconceptions.

Methods: Researchers procured 75 hand specimens from 41 adult cadavers through our institution's anatomical donations program.