An Analysis of Intrapitch Variation in Joint and Segment Velocities With Throwing Arm Kinetics in High School and Professional Baseball Pitchers.

BACKGROUND: Improper sequencing order of maximal joint and segment velocities has been identified as an important predictor for both throwing arm kinetics and ball velocity. PURPOSE: To investigate the intrapitcher variation of maximal segment velocities and the relationship to throwing arm kinetics and ball velocity in high school (HS) and professional (PRO) pitchers. STUDY DESIGN: Descriptive laboratory study. METHODS: HS (n = 59) and PRO (n = 338) pitchers, instructed to throw 8 to 12 fastball pitches, were evaluated with 3-dimensional motion capture (480 Hz). Maximal joint and segment velocities were calculated for each pitch, and the standard deviation of the maxima was calculated per pitcher. These standard deviations were used to classify pitchers as "low variance" or "high variance" for each segmental velocity subgroup, "overall low variance" or "overall high variance" based on cumulative segment velocity variation, or "population," with any pitcher eligible to be included in multiple subcategories. Maximal velocities and throwing arm kinetics were compared among the various subgroups. RESULTS: The HS low-variance shoulder internal rotation velocity subgroup (4949 ± 642 deg/s) had significantly lower maximal shoulder internal rotation velocity compared with HS population (5774 ± 1057 deg/s) (P < .001); similar findings were observed for PROs (5269 ± 835 vs 5824 ± 1076 deg/s; P < .001), as well as lower shoulder superior force compared with the PRO population (14.8% ± 8.8% vs 17.8% ± 8.8% body weight; P = .001). The PRO low-variance lead knee extension velocity subgroup had significantly lower maximal lead knee extension velocity (216 ± 135 vs 258 ± 125 deg/s; P = .001) and shoulder distractive force (111.5% ± 14.4% vs 115.6% ± 15.9% body weight; P = .003) compared with the PRO population. The PRO overall low-variance subgroup had significantly lower shoulder distractive force (111.8% ± 14.1% vs 119.6% ± 15.5% body weight; P = .008) and elbow anterior force (40.6% ± 5.0% vs 43.6% ± 6.2% body weight; P = .008) compared with the PRO overall high-variance subgroup. CONCLUSION: HS and PRO pitchers with low variance for joint and segment velocities achieved significantly lower maximal velocities in the subgroup of interest, while preserving ball velocity. PRO pitchers with overall low variance among multiple maximal joint and segment velocities demonstrated decreased shoulder distractive and elbow anterior force. CLINICAL RELEVANCE: PRO pitchers with low intrapitch variation in maximal joint and segment velocities may be viewed as kinetically conservative throwers. These pitchers with similarly maintained mechanics between pitches may have an increasingly regimented form that preserves kinetic forces about the throwing arm. The opposite may be true for PRO pitchers with increased variability in segmental velocities during their pitching motion, as they showed increased throwing arm kinetics including shoulder distractive and elbow anterior force compared with the overall low-variance group, theoretically increasing their risk of injury.

High Rate of Clinically Meaningful Achievement in Outcomes After Subacromial Balloon Spacer Implantation for Massive Irreparable Rotator Cuff Tears: A Systematic Review and Meta-analysis.

BACKGROUND: Subacromial balloon spacers have been introduced as a potential treatment option for patients with massive irreparable rotator cuff tears. However, it is important to comprehensively assess the clinical efficacy of this procedure in the context of an increasing amount of contemporary literature. PURPOSE: To perform a systematic review of the contemporary literature to understand the propensity for clinically meaningful improvements after subacromial balloon spacer implantation for massive irreparable rotator cuff tears. STUDY DESIGN: Systematic review and meta-analysis; Level of evidence, 4. METHODS: The PubMed, Ovid/MEDLINE, and Cochrane databases were queried in July 2022 for data pertaining to studies reporting clinically significant outcomes after subacromial balloon spacer implantation. Freeman-Tukey double arcsine transformation was used to quantify the pooled rate of clinically meaningful improvements in outcomes as evaluated using the minimal clinically important difference (MCID), Patient Acceptable Symptom State (PASS), and substantial clinical benefit (SCB). Qualitative analysis was performed when data were variably presented to avoid misleading reporting. RESULTS: There were 10 studies included, all of which reported MCID achievement. The overall pooled rate of MCID achievement for the Constant-Murley score was 83% (95% CI, 71%-93%; range, 40%-98%), with 6 of 8 studies reporting rates equal to or exceeding 85%. One study reported a 98% rate of PASS achievement for the Constant-Murley score at 3-year follow-up. The rate of MCID achievement for the American Shoulder and Elbow Surgeons (ASES) score ranged between 83% and 87.5%. The rate of PASS achievement for the ASES score was 56% at 2-year follow-up, while the rate of SCB achievement for the ASES score was 83% and 82% at 1- and 2-year follow-up, respectively. At 1-year follow-up, 74% and 78% of patients achieved the MCID for the Numeric Rating Scale and Oxford Shoulder Score, respectively. At 3 years, 69% of patients achieved the MCID for the Numeric Rating Scale and 87% achieved it for the Oxford Shoulder Score. CONCLUSION: Patients who underwent isolated subacromial balloon spacer implantation for massive irreparable rotator cuff tears demonstrated a high rate of clinically significant improvement in outcomes at short- to mid-term follow-up. A paucity of literature exists to appropriately define and evaluate the rates of achieving the PASS and SCB after subacromial balloon spacer implantation, necessitating further study.

The Twizzler: a modified primary closure for distal lower extremity wound reconstruction utilizing a dynamic winch stitch.

Management of lower extremity wounds following successful tumor excision presents multiple challenges. Distal lower extremity integument is highly prone to edema often lacks adequate skin laxity for standard primary closures. The closure must be resilient enough to withstand mobility. As a result, optimal reconstruction may include skin grafting, rotational flaps, free tissue transfers, healing by second intention, or some combination. These methods may involve multiple steps in reconstruction, a prolonged recovery period, increased cost, and higher infection risk. We propose a modified primary closure that takes advantage of the visco-elastic properties of the skin without introducing additional components or steps. This technique is initiated with percutaneous suture in order to intermittently stretch the skin with constant tension. This load cycling allows for lower extremity skin to stretch over time and ultimately reduce wound edge tension, allowing for ease of absorbable suture placement. The Twizzler technique is cost-effective, uses readily available supplies, and effectively closes relatively large defects on the lower extremities.