bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinical Utility Of An MRI Based Classification For Operative Versus Non-operative Management Of UCL Tears: Two-year Follow Up
Authors: Ramkumar Prem N. , Haeberle Heather S. , Navarro Sergio M. , Frangiamore Salvatore Joseph , Farrow Lutul D. , Schickendantz Mark S.
Published: July 2019

Objectives:

A recently introduced classification of medial ulnar collateral ligament (UCL) tears accounting for location and severity has demonstrated high interobserver and intraobserver reliability, but little is known about its clinical utility. The purpose of this study was to assess the relationship of the MRI-based classification system in predicting which athletes succeeded non-operative versus operative treatment after completing a standardized rehabilitative program. Secondary objectives included sub-analysis of baseball players, including return-to-play (RTP) and return-to-prior performance (RPP).

Methods:

After a priori power analysis, 58 consecutive patients with UCL tears and a minimum of two-year follow-up were retrospectively classified into those succeeding operative versus non-operative treatments. The MRI-based classification system accounting for UCL tear location and severity were correlated with non-operative and operative cohorts. Sub-analyses for baseball players, including RTP and RPP, were performed.

Results:

A total of 58 patients (40 baseball players, 34 pitchers) met inclusion criteria. A total of 35 patients (32 baseball players, 27 pitchers) underwent surgery, and 23 patients (8 baseball players, 7 pitchers) completed non-operative management. No patients in the non-operative arm crossed over to surgery after completing the rehabilitative program. Patients with distal (OR: 48.0, p=0.0004) and complete (OR: 5.4, p=0.004) tears were more likely to undergo surgery. Baseball players, regardless of position, were confounding determinants of operative management, although there was no difference in RTP and RPP between treatment arms.

Conclusion:

A six-stage MRI-based classification addressing UCL tear grade and location may confer early decision-making as patients likely to fail non-operative treatment have complete, distal tears whereas those with proximal, partial tears may be more amenable to non-operative modalities. [Table: see text]
Early Surgical Intervention for Femoroacetabular Impingement Syndrome Provides Clinically Significant Outcome Improvement
Authors: Kunze Kyle N. , Beck Edward C. , Nwachukwu Benedict Uchenna , Ahn Junyoung , Nho Shane Jay
Published: July 2019

Objectives:

The purpose of the current study is to assess the outcomes of hip arthroscopy for FAIS according-timing of surgical intervention.

Methods:

Patients undergoing arthroscopic intervention for FAIS with minimum two year follow-up were included. All patients completed the hip outcome score (HOS)-activities of daily living (ADL), HOS-sports subscale (HOS-SS), modified Harris hip score (mHHS), international hip outcome tool-12 (IHOT-12), and visual analog scales (VAS) for pain and satisfaction. Patients were stratified by time with FAIS symptoms until surgical intervention. We compared 3-6 months of symptoms with other subsequent time frames (6-12 months, 12-24 months, and >24 months). Clinically significant outcome was determined using the minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS).

Results:

A total of 1,094 patients with mean (+ standard deviation) age 32.3+12.4 years and follow-up 30.8+6.7 (range:24-58) months were included. Patients undergoing surgery at 3-6 months of symptoms had no significant differences in outcome compared-those in the 6-12 month group except for the IHOT-12 (p:0.028). Patients with symptom duration of 12-24 months and greater than 24 months had worse outcome across all outcome measures (p<0.0001 for symptoms >24 months). Patients in the 3-6 month symptom group had increased likelihood for achieving MCID on HOS ADL (OR:1.81; 1.20-2.73), and HOS-SS (OR:1.90; 1.11-3.17), as well as PASS on the HOS-ADL (OR:1.85; 1.34-2.56) and HOS-SS (OR:1.58; 1.14-2.18). In multivariate regression analysis, symptom duration was the most predictive of VAS pain (Beta:3.10, 95% Confidence Interval [95%CI]:1.56-4.63; p<0.001) and satisfaction scores (Beta:-4.16, 95%CI:-6.14- -2.18; p<0.001).

Conclusion:

In patients with FAIS, surgical intervention early after the onset of symptoms (3-6 months) is associated with superior outcomes when compared to patients who underwent surgical intervention beyond this time frame. This information may help guide preoperative decision making on behalf of surgeons and patients who are considering delaying intervention. [Table: see text]
Comparison of Tendon Lengthening with Traditional vs. Accelerated Rehab Following Achilles Tendon Repair: A Randomized Controlled Trial
Authors: Okoroha Kelechi , Ussef Najib , Eller Erik , Zeni Ferras , Moutzouros Vasilios
Published: July 2019

Objectives:

Operative repair of Achilles tendon ruptures have shown successful outcomes. However, little is know about the amount of tendon or repair site lengthening after repair and if lengthening is affected by rehab protocols. The purpose of our study was to compare lengthening of the Achilles tendon after surgical repair, comparing traditional and accelerated rehab protocols.

Methods:

Twenty patients undergoing primary repair of Achilles tendon ruptures were assessed for participation. We performed a prospective randomized controlled trial in accordance with the CONSORT (Consolidated Standards of Reporting Trials) 2010 statement. The study arms included operative repair of Achilles tendon rupture with either accelerated (graduated weight bearing at 2 weeks) or traditional rehab (weight bearing at 6 weeks). During repair, two 2-mm tantalum beads with laser-etched holes were sutured to the Achilles tendon at the repair site. Beads were evaluated via CT scans immediately post-operatively and at 12 weeks. X-rays were obtained at time 0 and then at 2, 6, and 12 weeks. The primary outcome of the study was the difference in tendon or repair site lengthening between the study arms. Randomization was by a computerized algorithm. The observer was blinded and the patient was not blinded to the intervention.

Results:

Zero patients declined participation and all 20 patients were included for final analysis. All patients showed statistically significant lengthening at two weeks following surgery. There was a trend toward increased lengthening at 6 weeks in the accelerated rehab group (9.9 mm, range 2.6 -13.9 mm) compared to the traditional rehab group (4.1 mm, range 1.5 -9.0 mm), although this was not statistically significant; p = .07. However the final amount of tendon lengthening at 12 weeks after surgery was not different between the accelerated rehab group (14.4 mm, range 11.7 -17.0 mm) and the traditional rehab group (13.4 mm, range 10.7 -17.0 mm); p = .38.

Conclusion:

This study’s findings suggest that all patients undergoing operative repair of Achilles tendon ruptures have significant lengthening after surgery. Although there was a trend toward increased lengthening at 6 weeks in the accelerated rehab group, there was no difference in tendon lengthening at final follow up between the two groups.
Electromyographic Evidence of Excessive Achilles Tendon Elongation During Isometric Contractions After Achilles Tendon Repair
Authors: McHugh Malachy P. , Orishimo Karl F. , Kremenic Ian J. , Adelman Julia , Nicholas Stephen J.
Published: July 2019

Objectives:

It has been proposed that increased tendon elongation after Achilles tendon repair contributes to selective weakness in end-range plantar flexion (Mullaney et al 2006). Excessive tendon elongation during maximum voluntary contraction (MVC) means greater muscle fiber shortening. Since mean frequency (MF) of the electromyogram (EMG) increases with muscle fiber shortening, it was hypothesized that during isometric plantar flexor MVCs MF would be higher on the involved versus non-involved side. Therefore, the purpose of this study was to examine MF during isometric MVCs in patients with Achilles tendon repairs.

Methods:

Maximum isometric plantar flexion torque was measured at 20° and 10° dorsiflexion, neutral, and 10° and 20° plantar flexion in 17 patients (mean±SD age, 39±9 years; 15 men, 2 women) 43±24 months after surgery (range, 9 months to 8 years). Surface EMG signals were recorded during strength tests. MF was calculated from Fast Fourier Transforms of medial gastroc (MG) lateral gastroc (LG) and soleus (S) EMG signals. Effect of weakness on MF was assessed using analysis of variance. Based on reported plantar flexor MF values it was estimated that with 17 subjects there would be 80% power to detect a 16% difference in MF between involved and noninvolved legs at P<0.05.

Results:

Patients had marked weakness in 20° plantar flexion (deficit 28±18%, P<0.01; 14 of 17 deficit >20%) but no significant weakness in 20° dorsiflexion (deficit 8±15%, P=0.20; 4 of 17 deficit >20%). MF increased moving from dorsiflexion to plantar flexion (P<0.001) but overall was not different between involved and noninvolved sides (P=0.22). However, differences in MF between the involved and noninvolved sides were apparent in the patients with marked weakness. At 10° plantar flexion 8 of 17 patients had marked weakness (>20% deficit). MF at 10° plantar flexion was significantly higher on involved versus noninvolved side in patients with weakness but this was not apparent in patients with no weakness (side by group P=0.014; Table 1). MF at 10° plantar flexion average across the 3 muscles was 13% higher on the involved versus noninvolved side in patients with weakness (P=0.012) versus 3% lower in patients with no weakness (P=0.47).

Conclusion:

Higher MF on the involved versus noninvolved side in patients with significant plantar flexion weakness is consistent with greater muscle fiber shortening. This indicates that weakness was primarily due to excessive lengthening of the repaired Achilles tendon. If weakness were simply due to atrophy, a lower MF would have been be expected and patients would have had weakness throughout the range of motion. Surgical and rehabilitative strategies are needed to prevent excessive tendon elongation and weakness in end-range plantar flexion after Achilles repair. [Table: see text]
High Rate of Recurrent Meniscus Tear and Lateral Compartment Osteoarthritis in Patients Treated for Symptomatic Lateral Discoid Meniscus: A Long-Term Population-Based Study
Authors: Sabbag Orlando , Hevesi Mario , Sanders Thomas L. , Camp Christopher L. , Dahm Diane L. , Levy Bruce A. , Stuart Michael J. , Krych Aaron John
Published: July 2019

Objectives:

Little is known about the natural history and long-term outcome of a surgically treated symptomatic lateral discoid meniscus. The goals of this study were to describe the rate and factors associated with recurrent lateral meniscus tears and progression to symptomatic lateral compartment osteoarthritis (OA) in patients surgically treated for a symptomatic lateral discoid meniscus. Patients with surgically treated lateral discoid meniscus have a high incidence of meniscus re-tear and progression to lateral compartment OA.

Methods:

A large, geographic database was reviewed to identify and confirm patients presenting with symptomatic lateral discoid meniscus between 1998 and 2015. Charts were reviewed to document treatment and outcomes at a minimum clinical follow-up of two years.

Results:

70 discoid meniscus patients (30 F, 40 M) with a mean age of 27 years (Range: 2.0-66.0) were followed for an average of 5.8 years (Range 2.0-23.7). Sixty patients underwent surgical management: 49 (82%) patients underwent partial lateral meniscectomy and 11 (18%) underwent meniscus repair (including saucerization). Tear-free survival following surgery was 93% at 2 years, 69% at 5 years, and 40% at 8 years. Overall progression to symptomatic lateral compartment OA in the surgical group was 10% at 2 years, 23% at 5 years, and 48% at 8 years. Of those patients who developed lateral compartment OA, 55% (11/20) had a Kellgren-Lawrence score 2 or greater at last radiographic follow-up. Young age and open growth plates were associated with increased incidence of postoperative re-tear (HR: 0.96, CI: 0.93-0.99, p = 0.01). Increased age at diagnosis and BMI ≥ 30 were associated with increased risk of progression to lateral compartment OA on final radiographs.

Conclusion:

Patients with a surgically treated lateral discoid meniscus tear had a high rate of recurrent meniscus tear at long-term follow-up (60% at 8 years) that was associated with young age. Approximately 48% of surgically treated patients developed symptomatic lateral compartment OA at eight years from initial presentation. The risk of progression to OA increased with older age at diagnosis and BMI ≥ 30.
The Proximal and Distal Effects of Blood Flow Restriction Therapy on Upper and Lower Extremity Strengthening: A Randomized Controlled Trial
Authors: Bowman Eric N. , El-shaar Rami , Milligan Heather , Jue Greg , Mohr Karen , Brown Patty , Watanabe Drew M. , Limpisvasti Orr
Published: July 2019

Objectives:

Blood flow restriction (BFR) therapy consists of low-intensity exercise performed under reduced venous return due to an inflatable tourniquet. This produces similar physiologic and clinical effects to high-intensity routines with less joint and tissue stress. Postoperative patients may benefit from more efficient rehabilitation. Proximal and distal effects of BFR have been evaluated, however, minimal literature exists on its use in orthopaedic conditions. The purpose of this study was to determine the effects of low-intensity BFR therapy both proximal and distal, in the upper and lower extremities.

Methods:

This was a prospective, randomized controlled trial of healthy subjects completing a standardized 6-week course of BFR therapy. Subjects were randomized to BFR therapy on one extremity or to a control group. Subjects were excluded for cardiac, pulmonary, or hematologic disease, pregnancy, or previous surgery in the extremity. Data collected at baseline and completion included: limb circumferences, isokinetic, and manual strength testing.

Results:

Forty subjects completed the protocol. Average age was 27.7 years; 54% were female. For both upper and lower extremity groups, a statistically significant increase was observed in manual and isokinetic strength both proximal and distal to the BFR tourniquet when compared to both the non-tourniquet extremity and the control group (p<0.05). Limb circumference significantly increased in the upper (p<0.01) and lower extremities (p=0.02). A significant increase in manual strength was noted in shoulder abduction and scaption, and hip extension and abduction even in the non-tourniquet BFR extremity compared to the control group (p<0.05).

Conclusion:

Low-intensity BFR therapy led to greater increases in muscle strength and hypertrophy. Similar strengthening effects were seen in proximal and distal muscle groups. Strength increases in the contralateral BFR extremity may corroborate a systemic effect. This study provides data to further evaluate the efficacy and safety of BFR therapy in operative and non-operative orthopaedic conditions. [Table: see text]
Risk Factors for Recurrent Anterior Shoulder Instability after Arthroscopic Stabilization in Adolescent Athletes
Authors: Cheng Timothy , Edmonds Eric W. , Bastrom Tracey P. , Pennock Andrew T.
Published: July 2019

Objectives:

Arthroscopic stabilization has become the preferred surgery for adolescent athletes with anterior instability without significant bone loss. Although successful for most patients, 10-40% will experience recurrent instability. The purpose of the current study was to compare a consecutive series of patients who had failed an arthroscopic stabilization to an age and gender matched cohort of patients who had no evidence of recurrent instability with a goal of identifying risk factors for future instability.

Methods:

A retrospective review was undertaken of all patients undergoing an arthroscopic shoulder stabilization for anterior instability between 2009 and 2016. Patients over the age of 18 years and those with underlying syndromes affecting the musculoskeletal system were excluded. Two patient cohorts were identified: (1) Patients with recurrent instability (frank dislocations or subluxations) after their arthroscopic stabilization; (2) An age and gender matched cohort of patients with no recurrent instability at a minimum of 2 years follow-up from surgery. Patient demographic, injury, radiographic, and surgical variables were recorded. In particular, bone loss measurements were performed on both the glenoid and humerus, and Hill-Sachs lesions were classified as “on-track” or ”off-track”. Variables at p<0.10 on univariate analysis were entered into a binary logistic multivariate regression analysis.

Results:

35 patients were identified that failed an arthroscopic stabilization at a mean of 1.2 ± 1.0 years after their index surgery. A separate age and gender matched cohort of 35 patients was also identified with no symptoms of recurrent instability. Univariate analysis identified the following 4 risk factors for recurrent instability (glenoid bone loss > 10%, glenoid retroversion < 5◦, skeletal immaturity, and patients with more than one pre-surgical instability event). Collision sport participation, the presence and size of a Hill-Sachs deformity, and the glenoid track were not predictive of failure. Multivariate regression analysis revealed that loss of glenoid retroversion, skeletal immaturity, and a greater number of prior instability events best predicted future recurrence with two risk factors having a 3x increased risk and patients with all three risk factors having a 4x increased risk of recurrent instability after arthroscopic stabilization.

Conclusion:

Anterior glenoid bone loss, glenoid version, skeletal immaturity, and multiple pre-operative instability events are risk factors for failed arthroscopic stabilization in adolescent athletes with anterior instability. In the setting of multiple risk factors, patients and families should be counselled of the increased odds of surgical failure and other forms of surgical stabilization may need to be considered.
Oral Contraceptives Provide Protection against Anterior Cruciate Ligament Tears: A National Database Study of 165,748 Female Patients
Authors: DeFroda Steven F. , Bokshan Steven Louis , Worobey Samantha , Ready Lauren , Daniels Alan H. , Owens Brett D.
Published: July 2019

Objectives:

ACL tears are more prevalent in females than males. One of the factors responsible for this may be the variation in levels of estrogen and progesterone. The purpose of this study was to query a large nationwide database to determine the potentially protective effects of oral contraceptive pills (OCPs) on ACL tears. We hypothesized that females taking OCPs would exhibit ACL tears at lower rates than a matched population of patients not taking OCPs.

Methods:

The PearlDiver database (www.pearldiverinc.com, Fort Wayne, IN) was queried for all OCP users amongst females aged 15-49. Female experiencing an ACL tear and undergoing surgery (CPT 29888) were compared to a control group of females undergoing surgery for an ACL tear, but not on OCPs. Patients were matched by age and Charlson comorbidity score. Chi-squared testing was used to assess for significant differences in the rate of ACL tears for the OCP and non-OCP users, according to age groups broken down into age intervals of 5 years.

Results:

There were a total 82,874 patients in both the OCP and non-OCP groups. There were a total of 569 (0.69%) ACL tears in the non-OCP group and 465 (0.56%) in the OCP group (p<0.001). In the non-OCP group, patients aged 15-19 accounted for 29.35% of all ACL tears, whereas, in the OCP group, this same age group only accounted for 13.33% of ACL tears. Among all age groups, the odds ratios for experiencing an ACL tear while on OCP was 0.82 (χ2=0.001, 95% CI 0.72-0.92) (Figure 1) compared to not using OCP. This protective effect was driven primarily by the 15-19 age group (odds ratio 0.37 (χ2<0.001, 95% CI 0.27-0.50)).

Conclusion:

This investigation utilizing a large national database found that usage of OCPs was associated with an 18% decrease in the risk of ACL tear when compared to a matched population of patients with ACL tears not taking OCPs. These findings were in line with smaller studies which demonstrated similar results. Additionally, it was shown that OCPs were most protective in the 15-19 year old age group, with a 63% reduction in tears in this group. Ongoing randomized trials in patients without ACL tear could help to demonstrate further clinical evidence for OCP usage as a way to modify risk factors for ACL tear. While clinical evidence is limited, there should be strong consideration for OCP usage in elite high school and college aged athletes, especially those who are at risk of ACL tear.
Performance and Return to Sport Following Open Reduction Internal Fixation About the Elbow in Professional Baseball Players
Authors: Erickson Brandon J. , Chalmers Peter Nissen , D’Angelo John , Ma Kevin , Romeo Anthony A.
Published: July 2019

Objectives:

The results of open reduction and internal fixation (ORIF) of stress reactions and fractures of the olecranon in professional baseball players with regards to return to sport (RTS) are unknown. The purpose was to determine the RTS rate and performance in professional baseball players following ORIF of acute, displaced olecranon fractures and olecranon stress fractures, and to compare RTS rate and performance to matched controls. The authors hypothesized that there is a high rate of RTS in professional baseball players following ORIF of acute, displaced olecranon fractures and olecranon stress fractures with no significant difference in rate of RTS or performance, specifically related to the primary outcome performance variables of win-loss percentage (W-L%), WHIP ((walks +hits)/innings pitched), fielding independent pitching (FIP), and wins above replacement (WAR)) between cases and controls between cases and controls.

Methods:

All professional baseball players who underwent ORIF of the olecranon between 2010-2016 were included. Demographic and performance data (pre and post surgery) for each player was recorded. Performance metrics were then compared between cases and a group of matched controls.

Results:

Overall, 52 professional baseball players (average age 22.6 +/- 3.6 years) underwent ORIF of an olecranon fracture. The majority of players sustained a primary olecranon stress fracture (73%), that was fixed with one screw (60%), with a RTS rate of 67.5%. No difference in RTS rate existed between matched controls and the players. No significant difference existed between the primary preoperative and postoperative performance (change in performance) metrics for pitchers who underwent ORIF of an acute, displaced olecranon fracture or ORIF of a primary olecranon stress fracture. No significant difference existed between pitchers who underwent ORIF of a primary olecranon stress fracture and matched controls in any of the primary performance metrics.

Conclusion:

Professional baseball players who undergo ORIF of an olecranon fracture (either acute, displaced or stress fracture) have a RTS rate of 67.5%, which is no different than natural attrition from matched controls. No decline in performance metrics is seen in players who are able to RTS when compared to their preoperative performance, or to the performance of matched controls.
Arthroscopic debridement versus refixation of the acetabular labrum associated with femoroacetabular impingement: Updated mean 7 year follow-up
Authors: Larson Christopher M. , Giveans M. Russell , McGaver Rebecca Stone , Weed Katelyn N.
Published: July 2019

Objectives:

The acetabular labrum provides sealing function and a degree of hip joint stability. Previous early (16 month) and mid-term (mean 3.5 years) follow-up of this cohort reported better patient related outcome measures in the refixation group. To update the results of labral refixation versus focal labral excision/debridement in a cohort of patients who underwent arthroscopic correction of femoroacetabular impingement (FAI).

Methods:

We reported patients who underwent labral debridement/focal labral excision during a period before the development of labral repair techniques. Patients with labral tears thought to be repairable with our current arthroscopic technique were compared with patients who underwent labral refixation. In 46 hips, the labrum was focally excised/debrided (group 1); in 54 hips, the labrum was refixed (group 2). Outcomes were measured with modified-Harris-Hip-Score (mHHS), Short Form-12 (SF-12), and a visual-analog-scale (VAS) for pain preoperatively and postoperatively.

Results:

Mean age was 33 years in group 1 and 28 years in group 2 with mean follow-up of 7 years (range, 2-13.6 years). At mean follow-up, subjective outcomes were significantly improved (P<.01) for both groups compared with preoperative scores. The mHHS (P=.004), SF-12 (P=.016), and VAS pain scores (P<.001) were all significantly better for refixation group compared with debridement group. Although most recent outcomes for both groups fell at mean 7 years’ follow-up in comparison to 16 month and 3.5 year follow-up, the disparity between groups was greater in favor of labral refixation. Good-to-excellent results were 47.7% in debridement and 82.4% in refixation (p<.001), and failure rates were 31.8% (debridement) and 13.7% (refixation group) (p =.034). There were 4 revisions in the debridement group and none in the refixation group.

Conclusion:

Longer term follow-up comparing focal labral debridement/excision to refixation revealed a decrease in patient related outcome scoring and good/excellent results in both groups. Ultimately, there was a greater drop in outcome measures and good/excellent results in the debridement group and better maintenance of results in the refixation group at mean 7 years follow-up.
Variability in Baseball Throwing Metrics During A Structured Long-toss Program: Does One Size Fit All?
Authors: Leafblad Nels , Larson Dirk , Fleisig Glenn S. , Conte Stan , Fealy Stephen , Dines Joshua , D’Angelo John , Camp Christopher L.
Published: July 2019

Objectives:

The variability of throwing metrics, particularly elbow torque and ball velocity, during structured long-toss programs is yet to be fully elucidated. The primary aims of this study were to assess various throwing metrics through a structured long-toss program using wearable technology and to quantify the intra and inter thrower variability of these metrics at each stage of throwing.

Methods:

This was a descriptive laboratory study in which 60 high school and collegiate pitchers participated in a predetermined, structured, progressive long-toss program. All players wore a motusBASEBALL sleeve (Motus Global, Inc.; Rockville Centre, NY), which measured arm slot, arm velocity, shoulder rotation, and elbow varus torque. Radar guns were used to measure ball velocity. These metrics were compared within and between all pitchers at each of the following throwing distances: 90 ft, 120 ft, 150 ft, 180 ft, and maximum effort mound pitching. Intra- and inter- thrower reliabilities were calculated for each throwing metric at every stage of the program. Excellent intra-thrower reliability was defined by an Intra-class coefficient (ICC) >0.750. Acceptable inter-thrower reliability was defined by a Coefficient of Variation (CV) <5%.

Results:

Ball velocity significantly changed at each progressive throwing distance, but this did not consistently correlate with an increase in elbow torque. Pitching from the mound did not place more torque on the elbow than throwing from 120 ft and beyond. Intra-thrower reliability was excellent throughout the progressive long-toss program for each throwing metric. Ninety-one percent of throwers had acceptable inter-thrower reliability for ball velocity, whereas only 79% of throwers had acceptable inter-thrower reliability for elbow torque.

Conclusion:

Based on trends in elbow torque, it may be practical to incorporate pitching from the mound earlier in the program (once a player is comfortable throwing from 120 ft). Ball velocity and elbow torque do not necessarily correlate with one another, so a degree of caution should be exercised when using radar guns to estimate elbow torque. Given the variability in elbow torque between throwers, some athletes would likely benefit from an individualized throwing program.
Are Baseball Statistics an Appropriate Tool for Assessing Return to Play in Injured Players: An Analysis of Statistically Variability in Healthy Players Using a Machine Learning Approach
Authors: Pareek Ayoosh , Parkes Chad W. , Leontovich Alexey A. , Bernard Christopher D. , Krych Aaron John , Dahm Diane L. , Camp Christopher L.
Published: July 2019

Objectives:

Traditional pitching statistics (ERA, WHIP, etc) have been used as surrogates for pitcher performance without being validated. Even amongst healthy pitchers, the normal variability of these parameters has not yet been established. The purpose of this study was to determine the normal variability of basic and advanced pitching statistics in non-injured Major League Baseball (MLB) pitchers. It is our hope that this work will serve as the foundation for the identification and implementation of validated, pitcher dependent statistical measures that can be used to assess return to play performance following injury.

Methods:

Publicly available data from MLB Statcast and Pitch/Fx databases was used to analyze all non-injured MLB pitchers during 2015 and 2016 seasons who pitcher greater than 100 innings each season without injury. Traditional and advanced baseball pitching statistics were analyzed. The variability of each parameter was assessed by computing coefficient of variation (CV) between individual pitchers and across all pitchers. A CV below 10 is typically indicative of a relatively constant parameter, and parameters with a CV > 10 are generally considered inconsistent and unreliable.

Results:

A total of 118 pitchers met all inclusion criteria. For each of these healthy pitchers, 38 basic/traditional parameters and 17 advanced parameters were analyzed. Of the traditional pitcher statistics, only 1 (3%) demonstrated a CV value < 10 (average fastball velocity [FBv]; CV 1.5) (Figure 1). In advanced statistics, 9 of 17 (53%) variables demonstrated acceptable consistency as evidenced by a CV value < 10 (Figure 2). Release position from plate (release_pos_y) along with velocity from the plate (vy0) where the two most constant advanced parameters. When separated by pitch type, these two parameters were the most constant (lowest CV) in every pitch type.

Conclusion:

The validity and variability of baseball statistics as surrogate markers for performance after injury/surgery have not yet been evaluated. It is critical that baseball statistics undergo proper vetting prior to being used to assess recovery. This study reveals average fastball velocity and release position from the plate to be the least variable basic and advanced baseball statistics in MLB pitchers. In total, only 10 of the 55 statistics analyzed demonstrated acceptable consistency and reliability. This study can be further used to determine the minimum time that each of these variables needs to be followed to ensure an appropriate sample size is obtained to detect significant differences in pre- and post- injury performance. [Figure: see text][Figure: see text]
A Comparison of Collegiate Women’s Court and Beach Volleyball Injury Data: A Three Year Retrospective analysis
Authors: Juhan Tristan , Kang Hyunwoo Paco , Homere Andrew , Jalali Omid , Tibone James E. , Gamradt Seth C. , Weber Alexander E.
Published: July 2019

Objectives:

NCAA Division I beach volleyball is a recently introduced sport that has been played for 3 seasons to date. Since the introduction of this new level of athletic participation for women’s’ beach volleyball, no study has been performed to compare the injury patterns between court and sand volleyball playing surfaces. The goal of this study is to compare the injury patterns and incidence in women’s collegiate court and beach volleyball in order to aid trainers, coaches and medical staff in effectively preparing and treating these collegiate athletes.

Methods:

A 3 year, retrospective review of all training room injury reports were analyzed for both beach and court volleyball from the 2015 through 2017 seasons. Non-athletic injuries or illness were excluded from analysis. Standardized injury rates for beach and court surfaces were calculated by normalizing the total number of injuries by the number of athletes and sets played. To compare the injury patterns among court versus beach volleyball players, injuries were categorized into one of six body regions (abdomen, lower extremity, upper extremity, thorax, head, and back). The proportion of injuries to each of these regions by playing surface was then calculated to compare injury patterns by playing surface. Chi-squared test and odds ratios were used to compare injury rates.

Results:

Between 2015 and 2017, 90 court volleyball injuries were recorded, while 49 beach volleyball injuries were recorded in the same time period. Court volleyball players had nearly quadruple the injury rate when compared to beach volleyball players, 0.039 and 0.010 injuries per athlete-set respectively (OR 4.05, 95%CI 2.85-5.76, p<0.0001). Court volleyball players suffered a higher proportion of lower extremity injuries when compared to beach volleyball players (51.5% vs. 12.8% respectively, p=0.004), and beach volleyball players suffered a significantly higher proportion of back injuries when compared to court volleyball players, (23.4% vs. 7.8% respectively, p=0.010).

Conclusion:

The data suggests a significantly higher incidence of injury for court volleyball players when normalized for gameplay exposure. There were, also significant differences in injury patterns with court volleyball players having a higher proportion of lower extremity injuries and beach volleyball having a higher proportion of back injuries. Recognizing these differences can aid in the establishment of preventative strength and conditioning programs as well as post training treatment protocols for these athletes which may increase both the individuals as well as the teams overall competitive success.
Hypovitaminosis D Is Not A Risk Factor for Stress Fracture or Reaction in NCAA Division I Track And Field
Authors: Lindsay Adam , Jalali Omid , Korber Shane , Romano Russ , Kang Hyunwoo Paco , Tibone James E. , Weber Alexander E. , Gamradt Seth C.
Published: July 2019

Objectives:

Most research on the role of vitamin D on skeletal health has been dedicated to the elderly for fracture prevention. However, there is a paucity of research examining the role of vitamin D in elite track and field athletes. The objective of this study was to evaluate the prevalence of stress reactions and fractures in NCAA Division I track and field athletes, and to determine the relationship between fractures and serum vitamin D levels.

Methods:

After IRB approval, we evaluated data for men’s and women’s outdoor track and field teams from 2015-2018 at a large NCAA Division I athletics program. Vitamin D levels were drawn during pre-season annual physicals. The cutoff for hypovitaminosis D was set at 40 nmol/L. Demographic and athletic tenure data were recorded and analyzed, and competitive events were grouped into one of four categories: 1) running events, 2) jumping events, 3) throwing events, and 4) multiple event types. Student T tests, chi-squared tests, and multivariate logistic regression were performed.

Results:

Of the 148 athletes analyzed, greater than 50% had hypovitaminois D (Figure 1). There were 29 (19.6%) athletes sustained a stress fracture or stress reaction. There was no difference in mean vitamin D levels in the injured group vs the non-injured group (43.55 ± 11.97 vs. 39.61 ± 12.32, respectively; p=0.122). Additionally, multivariate logistic regression failed to demonstrate an association between stress fracture or reaction incidence and vitamin D status, age, BMI, or event type (p>0.05 for all).

Conclusion:

These data suggest that NCAA Division I track and field athletes suffer a high rate of stress fractures and reactions, though those with hypovitaminosis D are not at increased risk of these injuries. This is the first study to demonstrate this in a heterogeneous population of elite athletes. Future studies investigating other modifiable risk factors for fracture in this population are warranted to prevent the health and athletic consequences of these fractures.
Concussions in the National Basketball Association: An Analysis from 1999-2018
Authors: Okoroha Kelechi , Patel Bhavik H. , Lu Yining , Idarraga Alexander J. , Forsythe Brian
Published: July 2019

Objectives:

Several studies have examined the incidence and effects of concussions in professional football, baseball, and hockey, but there has been limited evaluation of the effects of concussions in National Basketball Association (NBA) players. This study aims to evaluate the epidemiologic trends of concussions, as well as the effects of concussions on in-game performance, in NBA players.

Methods:

Publicly available records were searched to include all players who sustained an in-game concussion while playing in the NBA from the beginning of the 1999 NBA season to the conclusion of the 2018 season. For each player the following variables were collected: date of injury, number of days and games missed before returning to game play, player efficiency rating (PER) in the season of injury, the season preceding the injury, and the season following the injury, position of the injured player, and the incidence of multiple concussions for a single player. Concussion trends before and after the institution of the NBA Concussion Protocol were calculated, as well as the effects on PER after return to play.

Results:

From the start of the 1999 season to the end of the 2018 season, 185 basketball-related concussions were incurred across 149 NBA players. All players were able to return to play following a first-time concussion after missing an average of 7.7 days and 3.5 games. The NBA Concussion Protocol was instituted ahead of the 2011-2012 season, prior to which there were 5.7 concussions recorded/season, with an average of 6.7 days and 3.0 games missed per first-time concussion. Following the institution of the concussion protocol, there were approximately 11 more concussions recorded/season (16.7 vs. 5.7, P = 0.007), with 1.7 more days missed (8.4 vs. 6.7, P = 0.27) and 0.9 more games missed (3.9 vs. 3.0, P = 0.24) per concussion, compared to prior seasons. Of the 149 players who suffered concussions, 27 were concussed multiple times (18.1%). There was no difference found in the incidence of recurrent concussions within the same season before vs. after the institution of the concussion protocol (4 vs. 5, P > 0.05). PER was almost identical for concussed players in the season prior to the injury, the season in which the injury occurred, and the season following the injury (13.93 vs. 13.94 vs. 13.91, P = 0.998).

Conclusion:

There has been a significant increase in the incidence of concussions in the NBA player following the institution of a league-wide concussion protocol. This likely reflects more accurate reporting secondary to advances in player education, medical knowledge, national media coverage, and standardized testing protocols. Despite this increase in reported concussions, the amount of time missed following injury has remained relatively constant. Player performance as reported by PER was not significantly affected by sustaining a concussion. [Figure: see text][Table: see text]
Incidence of Game-Related, High School Football Lower Extremity and Surface Impact Trauma Requiring Elective Imaging and Surgery across Artificial Turf Systems of Various Infill Weight
Authors: Meyers Michael Clinton
Published: July 2019

Objectives:

Artificial turf surfaces are developed to duplicate playing characteristics of natural grass. With the newer generations of sand and rubber infill systems, infill weight is a common component that varies between fields. With the increasing concerns of rising medical costs, the potential for long-term articular changes, and perceived higher incidence of articular trauma while playing on artificial turf, infill weight could be a critical factor that could influence sport trauma and subsequent elective medical decisions. Therefore, this study quantified the incidence of game-related, high school football lower extremity and surface impact trauma requiring elective medical procedures across artificial turf systems of various infill weight.

Methods:

Artificial turf systems were divided into two sand/rubber infill weight groups by lbs per square foot: 6.0 to ≥9.0, and 0.0-5.9. Fifty-seven high schools participated across four states over 5 seasons. Outcomes of interest included elective medical procedures by injury category (player-turf surface impact trauma, trauma from shoe: surface interaction during physical collision/contact, trauma from shoe: surface interaction during physical noncontact). Data were subject to multivariate analyses of variance (MANOVA) and Wilks’ λ criteria using general linear model procedures.

Results:

Of 1,837 games documented, 1,049 games were played on 6.0 to ≥9.0 lbs infill/sq. ft, and 788 on 0.0-5.9 lbs infill/sq. ft, with 4,655 total injuries reported. MANOVA indicated a significant main effect across elective medical procedures by injury category (F3,3977 = 16.574; P < .0001). Post hoc analyses indicated significantly lower injury incidence rates (IIR per 10 game season) requiring radiography and MRI procedures following player-turf surface impact trauma [1.7, (95% CI, 1.5 -1.9) vs 3.2 (2.9-3.5); P = .001], trauma from shoe: surface interaction during physical collision/contact [2.4, (95% CI, 2.1-2.6) vs 3.2 (2.9-3.5); P = .001], and trauma from shoe: surface interaction during physical noncontact [0.4, (95% CI, 0.3-0.5) vs 0.7 (0.5-0.9); P = .01], while competing on the 6 to ≥9.0 lbs infill/sq. ft when compared to the lighter infill weight systems, respectively. No significant differences in surgical procedures by injury category were observed between infill weight.

Conclusion:

As the artificial infill surface weight decreased, the incidence of game-related, high school football lower extremity and surface impact trauma, and subsequent elective medical procedures significantly increased. Based on findings, high school football fields should minimally contain 6.0 to ≥9.0 lbs infill/sq. ft. This is the first longitudinal study to investigate the influence of artificial infill weight influence on high school sport trauma and elective medical decisions.
Outcomes of Concussion Injuries to Running Backs and Wide Receivers in the National Football League
Authors: Okoroha Kelechi R. , Jildeh Toufic Raja , Taylor Kevin , Buckley Patrick , Mehta Samir , Moutzouros Vasilios
Published: July 2019

Objectives:

Concussion injuries are common in professional football players, however the impact on player careers remains unclear. The purpose of this study was to quantify the effect of concussions on professional football player performance.

Methods:

Concussion data from the National Football League was collected for a period of four seasons (2012-2015) for running backs and wide receivers. Demographic variables (age, experience, position, time to return, yearly total yards and touchdowns) were recorded. Power ratings (total yards divided by 10 plus touchdowns multiplied by 6) were calculated for the injury season as well as for the 3 seasons before and after the injury. A control group consisted of running backs and wide receivers without an identified concussion injury who competed in the 2014 season.

Results:

One hundred and eighteen running backs and wide receivers sustained a concussion over a 4-season period, 25 players (21%) never returned to a National Football League game. Players were able to return in an average of 18.5 ± 8.2 days, missing 1.6 ± 1.0 games. For 18 players with a minimum total power rating of (sum of 4 seasons) of 200 points, power rating per game decreased 43.4 ± 0.4 points from three seasons prior to the concussion to three years postinjury. This change in performance was not statistically significant (P=0.422) when compared with the change for the 343 control players.

Conclusion:

Over one fifth of National Football League running backs and wide receivers who sustain a concussion never return to play in a game. On return to competition, player performance of injured players reduced from before injury, however there was no difference compared to controls.
Characterizing the Prevalence of Cam-Type Hip Impingement in Women’s Professional Ice Hockey Players
Authors: Whitney Darryl C. , Baron Samuel L. , Kingery Matthew T. , Campbell Abigail L. , Gonzalez-Lomas Guillem , Carter Cordelia W.
Published: July 2019

Objectives:

Participation rates in women’s ice hockey is increasing in North America. Recent studies have demonstrated an increased prevalence of femoroacetabular impingement (FAI) in elite male ice hockey players, yet little is known about hip pathology of players in the National Women’s Hockey League (NWHL). The primary purpose of this study was to determine the prevalence of radiographic FAI in women’s professional ice hockey players. The secondary purpose was to analyze the relationship between the presence of radiographic cam deformity and hip ROM, clinical impingement signs and age of menarche.

Methods:

In this IRB-approved study, physical examination and demographic data were prospectively collected for 27 NWHL players. Alpha angles were measured on 45-degree Dunn views with an alpha angle >55° defined as cam-positive. Pearson correlations were performed to analyze the relationship between alpha angle and ROM measurements, clinical impingement signs and self-reported age of menarche. Players were grouped into those with and without cam impingement and group differences were assessed using the student’s t-test. Statistical significance was set at p<0.05.

Results:

Twenty-seven athletes were included in the study. Nineteen of the 27 players (70%) had radiologic evidence of cam-type impingement with alpha angle >55 degrees; 14 players (52%) had bilateral cam deformity. The average age of menarche was 13.9±1.5 years. There was a significant association between age of menarche and right alpha angle (R=0.57, CI [0.16, 0.81], p=0.011), as well as age of menarche and left alpha angle (R=0.48, CI [0.03, 0.77], p=0.039). There was no statistically significant association between alpha angle and any ROM measurement. Additionally, there was no difference in the incidence of clinical impingement for players with or without an alpha angle >55°.

Conclusion:

This study suggests that elite female ice hockey players have a significantly higher prevalence of cam-type morphology than the general population. The clinical significance of this radiographic finding is uncertain as the majority of these deformities seem to be asymptomatic. Interestingly, the positive association between alpha angle and age of menarche lends support to the etiological hypothesis that cam lesions are a result of activity-related stress at the proximal femoral physis. This data suggests that players with earlier menarche (and therefore earlier physeal closure) seem to be less vulnerable to the development of cam deformity of the proximal femur.