Stress ultrasound in baseball players with ulnar collateral ligament injuries: additional value for predicting rehabilitation outcome

Return to Sport After Ulnar Collateral Ligament Tears Treated with Platelet-Rich Plasma Injections is Influenced by Length of Rehabilitation and Leukocyte Content of Injections: A Systematic Review

PURPOSE

To analyze the current literature assessing return to sport (RTS) outcomes after platelet-rich plasma (PRP) injections for the nonoperative treatment of ulnar collateral ligament (UCL) injuries.

METHODS

A systematic review of PubMed, Embase, and Web of Science databases was conducted in June 2023 to identify studies assessing RTS after PRP injections for UCL injuries. Tear severity, leukocyte content of PRP, rehabilitation protocol, and RTS outcomes were collected. Heterogeneity was assessed through proportional random-effects models for RTS and return to preinjury level of play (RTLP) with subgroup analysis by rehabilitation length, leukocyte content of PRP, and tear severity.

RESULTS

Eight studies with 278 partial-thickness and 44 full-thickness tears were identified. The mean age of patients ranged from 17.3 to 26 years. The mean RTS time after injection ranged from 5.2 to 25.4 weeks. High heterogeneity was observed among studies, with RTS rates ranging from 46% to 100% (I2 = 83%) and RTLP rates ranging from 34% to 100% (I2 = 83%). Studies with the longest rehabilitation programs (12-14 weeks) had RTS rates of 87% to 100% (I2 = 0%). RTS rates among athletes treated with leukocyte-poor and leukocyte-rich PRP ranged from 73% to 100% (I2 = 30%) and 52% to 88% (I2 = 84%), respectively. Subanalysis of RTS by tear severity demonstrated high variability, with partial-thickness rates ranging from 59% to 100% (I2 = 55%) and full-thickness rates ranging from 27% to 100% (I2 = 63.2%).

CONCLUSIONS

Studies assessing RTS after PRP injections are highly heterogeneous; however, current data suggest nonoperative RTS and RTLP rates ranging from 46% to 100% and 34% to 100%, respectively. Studies with at least 12 weeks of rehabilitation and studies using leukocyte-poor PRP demonstrated low heterogeneity and greater RTS rates. Alternatively, high heterogeneity was observed among both partial- and full-thickness tears.

LEVEL OF EVIDENCE

Level IV, systematic review of Level III-IV studies.

Early Surgery for Partial Tears of the Ulnar Collateral Ligament May Be More Cost-Effective and Result in Longer Playing Careers Than Nonoperative Management for High-Level Baseball Pitchers: A Decision-Analytic Markov Model-Based Analysis

BACKGROUND

Nonoperative management versus early reconstruction for partial tears of the medial ulnar collateral ligament (MUCL) remains controversial, with the most common treatment options for partial tears consisting of rest, rehabilitation, platelet-rich plasma (PRP), and/or surgical intervention. However, whether the improved outcomes reported for treatments such as MUCL reconstruction (UCLR) or nonoperative management with a series of PRP injections justifies their increased upfront costs remains unknown.

PURPOSE

To compare the cost-effectiveness of an initial trial of physical therapy alone, an initial trial of physical therapy plus a series of PRP injections, and early UCLR to determine the preferred cost-effective treatment strategy for young, high-level baseball pitchers with partial tears of the MUCL and with aspirations to continue play at the next level (ie, collegiate and/or professional).

STUDY DESIGN

Economic and decision analysis; Level of evidence, 2.

METHODS

A Markov chain Monte Carlo probabilistic model was developed to evaluate the outcomes and costs of 1000 young, high-level, simulated pitchers undergoing nonoperative management with and without PRP versus early UCLR for partial MUCL tears. Utility values, return to play rates, and transition probabilities were derived from the published literature. Costs were determined based on the typical patient undergoing each treatment strategy at the authors' institution. Outcome measures included costs, acquired playing years (PYs), and the incremental cost-effectiveness ratio (ICER).

RESULTS

The mean total costs resulting from nonoperative management without PRP, nonoperative management with PRP, and early UCLR were $22,520, $24,800, and $43,992, respectively. On average, early UCLR produced an additional 4.0 PYs over the 10-year time horizon relative to nonoperative management, resulting in an ICER of $5395/PY, which falls well below the $50,000 willingness-to-pay threshold. Overall, early UCLR was determined to be the preferred cost-effective strategy in 77.5% of pitchers included in the microsimulation model, with nonoperative management with PRP determined to be the preferred strategy in 15% of pitchers and nonoperative management alone in 7.5% of pitchers.

CONCLUSION

Despite increased upfront costs, UCLR is a more cost-effective treatment option for partial tears of the MUCL than an initial trial of nonoperative management for most high-level baseball pitchers.

The ulnar collateral ligament response to valgus stress, repetitive pitching, and elbow muscle contraction in asymptomatic baseball pitchers

Background

In baseball, repetitive pitching leads to medial elbow injuries, particularly to the ulnar collateral ligament (UCL). To prevent pitchers from UCL injuries, it is important to quantify the response to elbow stress. Repetitive elbow external valgus torque and muscular fatigue induced by repetitive pitching could affect markers of the response, that is, humeroulnar joint gap and UCL morphology. The aims of the study were three-folded: to investigate the effect of (1) exerted handgrip force on the humeroulnar joint gap, (2) repetitive pitching on the humeroulnar joint gap and the UCL morphology, and (3) exerted handgrip force on the humeroulnar joint gap for different levels of elbow valgus stress is different after compared to before repetitive pitching in asymptomatic baseball pitchers.

Methods

Medial elbow ultrasound images were collected in 15 asymptomatic male baseball pitchers. Three levels of static elbow valgus stress (0N, 50N, 100N) were applied with a TELOS device before and after repetitive pitching and with or without handgrip force. These images were used to assess the humeroulnar joint gap size and UCL length and thickness. After 110 fastball pitches or when 80% self-perceived fatigue on a VAS scale was reached, participants were instructed to stop throwing. Repeated measures ANOVAs were used to statistically test significant differences.

Results

Handgrip force did not significantly affect the humeroulnar joint gap. The UCL thickness and length and the humeroulnar joint gap were also not different after compared to before repetitive pitching. While higher levels of applied valgus stress significantly increased the humeroulnar joint gap (P < .001), this effect was not significantly different in the interaction with handgrip force and repetitive pitching.

Conclusion

The humeroulnar joint gap changes for different levels of elbow valgus stress. However, adult baseball pitchers did not respond to elbow stress after a single pitching session with or without submaximal handgrip force in the humeroulnar joint gap and UCL morphology.

Return to Sport After Nonoperative Management of Elbow Ulnar Collateral Ligament Injuries: A Systematic Review and Meta-analysis

BACKGROUND

Elbow ulnar collateral ligament (UCL) injuries can result in significant functional impairment in throwing and overhead athletes. UCL reconstruction and repair are proven treatments to restore stability, but the efficacy of nonoperative management is unclear.

PURPOSE

To determine the rate of return to sports (RTS) and return to previous level of play (RTLP) in athletes sustaining medial elbow ulnar collateral ligament (UCL) injuries treated nonoperatively.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A literature search was performed using Scopus, PubMed, Medline, the Cochrane Database for Systematic Review, and the Cochrane Central Register for Controlled Trials according to the 2020 PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. Inclusion criteria were limited to level 1 to 4 human studies reporting on RTS outcomes after nonoperative management of UCL injuries.

RESULTS

A total of 15 studies, consisting of 365 patients with a mean age of 20.45 ± 3.26 years, were identified. Treatment primarily consisted of platelet-rich plasma (PRP) injections with physical therapy (n = 189 patients; n = 7 studies) versus physical therapy alone (n = 176 patients; n = 8 studies). The overall RTS rate was 79.7% and the overall RTLP rate was 77.9%. Increasing UCL injury severity grade was associated with lower RTS rates. The RTS rate for proximal tears (89.7%; n = 61/68) was significantly greater than that for distal tears (41.2%; n = 14/34) (P < .0001). No significant difference in RTS rate was seen in patients treated with PRP versus those who did not receive PRP (P = .757).

CONCLUSION

For athletes undergoing nonoperative management of UCL injuries, the overall RTS and RTLP rates were 79.7% and 77.9%, respectively, with excellent outcomes in grade 1 and grade 2 UCL injuries, specifically. The RTS rate for proximal tears was significantly higher than that for distal tears. Athletes were most commonly treated with PRP injection and physical therapy.

Correlation of Joint Space Widening on Valgus Stress Magnetic Resonance Imaging With Level of Play and Innings Pitched in Professional Pitchers

Background

Previous studies have described various techniques and confirmed the clinical utility of valgus stress radiography and stress ultrasound in overhead athletes. The addition of valgus stress and a high-resolution anatomic assessment of the elbow with magnetic resonance imaging (MRI) in the active throwing position (flexed elbow valgus external rotation [FEVER] view) can add valuable diagnostic or prognostic information in throwing athletes.

Purpose/Hypothesis

The purpose of this study was to evaluate findings on MRI and subsequent performance in professional throwing athletes. It was hypothesized that joint space widening in the FEVER view would be predictive of performance and the risk of subsequent injuries.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

All pitchers on 2 Major League Baseball teams who consented to participate during their preseason screening in 2019 and 2020 underwent standard and FEVER MRI, and performance data from the following season were recorded, including injuries, mean throwing velocity, number of innings pitched, strikeout percentage, walk percentage, weighted on-base average, and level of play reached (not signed, minor league, or major league). Categorical variables were compared using the Fisher exact test or chi-square test, and continuous variables were compared using the Kruskal-Wallis test, as appropriate. Ordered logistic regression was used to determine the independent factors predicting performance.

Results

A total of 91 players underwent preseason imaging, and all players had subsequent performance data available. Multivariate analysis revealed that when controlling for age, mean velocity, history of injuries, presence of symptoms, and history of ulnar collateral ligament reconstruction, increased absolute joint space widening was predictive of a lower level of play (β = -0.63; P = .042). Univariate analysis demonstrated a significant correlation between relative joint space widening and level of play reached (β = -0.54; P = .034). Relative joint space widening remained a significant predictor of level of play (β = -0.87; P = .012) on multivariate analysis. Multivariate analysis also showed that both absolute joint space widening (β = -13.50; P = .012) and relative joint space widening (β = -13.60; P = .026) were predictive of the number of innings pitched in the subsequent season.

Conclusion

The present study demonstrates that findings on MRI with valgus stress correlated with the level of play reached and number of innings pitched in professional throwing athletes.

The Role of Ultrasound in the Evaluation of Elbow Medial Ulnar Collateral Ligament Injuries in Throwing Athletes

PURPOSE OF REVIEW

Although ultrasound (US) imaging is commonly used to evaluate the elbow medial ulnar collateral ligament (mUCL) in throwing athletes, significant technical heterogeneity exists in the published literature and in practice. This has resulted in variable and often ambiguous US diagnostic criteria for mUCL injury. This review summarizes the literature on sonographic evaluation of the mUCL and outlines recommendations for consistent descriptive terminology, as well as future clinical and research applications.

RECENT FINDINGS

Both acute and chronic throwing loads in overhead athletes cause the mUCL to become thicker and more lax on stress testing, and these changes tend to revert after a period of prolonged rest. Stress US (SUS) can aid in the diagnosis of mUCL tears and may help identify athletes at risk of mUCL injury. Variability exists in terminology, elbow flexion angle, amount of stress applied, and technique of stress testing. Recent studies have suggested an injured elbow stress delta (SD-change in ulnohumeral joint (UHJ) space with valgus stress) of 2.4 mm and a stress delta difference (SDD-side-side difference in SD) of 1 mm each denote abnormal UHJ laxity due to mUCL injury. US imaging is a powerful and widely accessible tool in the evaluation elbow mUCL injuries. Sonologists should consider how their US techniques compare with published methods and use caution when applying diagnostic criteria outside of those circumstances. Currently, an SD of 2.4 mm and an SDD of 1 mm provide the best diagnostic accuracy for mUCL tears requiring surgery. Finally, preliminary work suggests that shear wave elastography may be helpful in evaluating the biomechanical properties of the mUCL, but additional research is needed.

EURO-MUSCULUS/USPRM Dynamic Ultrasound Protocols for Elbow

ABSTRACT

In this dynamic protocol, ultrasound examination of the elbow using different maneuvers is described for several/relevant elbow problems. Scanning videos are coupled with real-time patient examination videos for better understanding. The authors believe that this practical guide-prepared by an international consensus of several experts (EURO-MUSCULUS: European Musculoskeletal Ultrasound Study Group and USPRM: Ultrasound Study Group of ISPRM [International Society of Physical and Rehabilitation Medicine])-will help musculoskeletal physicians perform a better and uniform/standard approach.

Acute Ligament Injuries of the Elbow

Ulnar collateral, radial collateral, lateral ulnar collateral, and annular ligaments can be injured in an acute trauma, such as valgus stress in athletes and elbow dislocation. Recognizing normal anatomy in magnetic resonance imaging and ultrasonography studies is important to identify ligamentous abnormalities in these imaging modalities.

FEVER: The Flexed Elbow Valgus External Rotation View for MRI Evaluation of the Ulnar Collateral Ligament in Throwing Athletes-A Pilot Study in Major League Baseball Pitchers

Background: Ulnar collateral ligament (UCL) injuries are common in throwing athletes due to repetitive extreme valgus stress during overhead throwing maneuvers. Conventional positioning for elbow MRI provides suboptimal rendering of the UCL. Objective: To perform a prospective pilot study assessing the impact of a flexed elbow valgus external rotation (FEVER) view on ulnotrochlear (UT) joint space measurement and reader evaluation of the UCL when incorporated into standard elbow MRI in throwing athletes. Methods: A total of 44 Major League Baseball pitchers underwent elbow MRI including standard sequences and a coronal fat-saturated proton density-weighted sequence in the FEVER view that uses specific positioning maneuvers and sandbags to immobilize the elbow in valgus stress and visualize the UCL parallel to its long axis. Patients recorded pain during FEVER view [0 (none) to 10 (maximal)]. Two radiologists independently evaluated standard and FEVER views to measure the UT joint space, assess confidence in UCL-related findings, and assess the UCL as normal or abnormal. Results: Pain during FEVER view was: 0 (n=29), 1-3 (n=11), 4-7 (n=4), 8-10 (n=0). Intrareader agreement for UT joint space measurement was higher for FEVER [intraclass correlation coefficient (ICC)=0.92] than standard (ICC=0.54) views. Averaged between readers, mean UT joint space increase on FEVER compared with standard view was 1.80 mm (95% CI: 1.58, 2.03). Confidence was higher for FEVER than standard view for reader 1 for assessment of the UCL as normal versus abnormal (mean increase in confidence of 0.41), intensity of abnormal signal (0.44), injury grade (0.98), and retraction (0.20), and for reader 2, assessment of the UCL as normal versus abnormal (0.50), location of abnormal signal (0.42); intensity of abnormal signal (0.47), injury grade (0.89), and retraction (0.50). Readers 1 and 2 classified 3 and 2 additional UCLs as abnormal on FEVER compared with standard view; neither reader classified any UCL as abnormal in standard view but normal in FEVER view. Conclusion: The increased joint space width confirms elbow valgus stress with FEVER view. Diagnostic confidence increased, and additional UCLs were identified as abnormal. Clinical Impact: The FEVER view may improve MRI evaluation of the UCL in throwing athletes.

Return-to-play outcomes in high school baseball players after ulnar collateral ligament injuries: dynamic contributions of flexor digitorum superficialis function

BACKGROUND

Ulnar collateral ligament (UCL) injuries are common in baseball pitchers. The purpose of this study was to evaluate changes to medial elbow joint laxity under valgus stress, as well as under valgus stress with flexor digitorum superficialis (FDS) contraction, and its ability to predict rehabilitation outcomes.

METHODS

Sixty-one UCL injuries were diagnosed. All patients were high school students who initially received rehabilitation treatment. Rates of return to play and return to the same level of play or higher (RTSP) were calculated and correlated with joint gapping under the following conditions: elbow gravity valgus stress and intra-articular ring-down artifact (RDA) at rest, elbow gravity valgus stress, and elbow gravity valgus stress with maximum FDS contraction.

RESULTS

The overall RTSP rate in patients receiving nonoperative treatment was 83.6% (51 of 61 patients). The RDA at rest significantly differed between the RTSP and non-RTSP groups, with an odds ratio of 17.5. This result indicated that the RDA could be a predictor of rehabilitation outcomes. Moreover, there were significant differences in the RDA under gravity valgus stress conditions with FDS contraction between the 2 groups, with an odds ratio of 98.0. Multivariate logistic regression analysis identified 1 variable (RDA under valgus stress with FDS contraction) as the most significant predictive factor for successful treatment of UCL elbow injury.

CONCLUSIONS

UCL injuries in high school baseball players can be successfully treated nonoperatively in most cases. Stress ultrasound with FDS muscle contraction can help predict the potential for RTSP.

Predictors of Failure of Return to Play in Youth Baseball Players After Capitellar Osteochondritis Dissecans: Focus on Elbow Valgus Laxity and Radiocapitellar Congruity

BACKGROUND

Osteochondritis dissecans of the humeral capitellum (capitellar OCD) is a common injury among youth baseball players, but there are only a few studies that report on return to play with nonoperative treatment.

PURPOSE

To evaluate the medial elbow joint laxity under valgus stress and radiocapitellar congruity in patients with capitellar OCD and evaluate their relationship to predicting rehabilitation outcome.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Capitellar OCD was diagnosed in 81 patients included in our study. All patients were elementary school students who initially received rehabilitation treatment after injury. The rates of return to the same level of play or higher (RTSP) were calculated and correlated with the joint gap difference between the dominant and nondominant elbows using ultrasound and radiocapitellar congruity (proximal, lateral, and anterior radial translation length), which was assessed using plain radiographs of the dominant elbow.

RESULTS

The overall RTSP rates of patients with nonoperative treatment was 70.4% (57/81). The multivariate logistic regression analysis identified OCD classification (stage I, odds ratio [OR], 4.076; 95% CI, 1.171-14.190) and 1 continuous variable (proximal radial translation length on anteroposterior view, OR, 0.661; 95% CI, 0.479-0.911) as the significant predictive factors for outcome after nonoperative treatment.

CONCLUSION

The early stage of capitellar OCD in youth baseball players can be successfully treated nonoperatively in the majority of cases. The presence of proximal radial translation can predict the outcome of nonoperative management of capitellar OCD.

Ultrasonographic Technique, Appearance, and Diagnostic Accuracy for Common Elbow Sports Injuries

Ultrasonography is a valuable diagnostic imaging tool because of its availability, tolerability, low cost, and utility in real-time dynamic evaluation. Its use in diagnosing elbow injuries has expanded recently and continues to do so. In particular, stress ultrasonography represents a unique imaging technique that directly visualizes the ulnar collateral ligament (UCL) and allows the assessment of ligament laxity, offering an advantage over magnetic resonance imaging and magnetic resonance arthrography in this patient population. Furthermore, ultrasonography has shown particular usefulness in instances where invasive techniques might be less desirable. This is particularly important in athletes since more invasive procedures potentially result in lost time from their sport. Ultrasonography is an important imaging tool that complements a thorough history and physical examination in the evaluation of elbow injuries in athletes. The use of ultrasonography in orthopaedic sports medicine has been investigated previously; however, to our knowledge, there has been no comprehensive review regarding the utility of ultrasonography for common elbow injuries in athletes. The current study provides a comprehensive, detailed review of the utility and indications for the use of ultrasonography for common elbow injuries in athletes.

State of the Union on Ulnar Collateral Ligament Reconstruction in 2020: Indications, Techniques, and Outcomes

PURPOSE OF REVIEW

There has been a marked increase in the number of ulnar collateral ligament reconstructions performed annually and an associated increase in the amount of recent literature published. It is paramount that surgeons remain up to date on the current literature, as modern indications and surgical techniques continue to improve clinical outcomes.

RECENT FINDINGS

Our understanding of ulnar collateral ligament (UCL) injuries, treatment indications, and surgical techniques for UCL reconstruction continues to evolve. Despite the rapidly increasing amount of published literature on the topic, a clear and concise surgical algorithm is lacking. Studies have suggested a trend towards improved clinical outcomes and decreased complications with various modifications in UCL reconstruction techniques. Current sport-specific outcome studies have reported conflicting results regarding the effect of UCL reconstruction on an athlete's performance upon returning to sport. With the rising incidence of UCL reconstruction and growing media attention, UCL injuries, reconstruction techniques, and return to sport following UCL surgery are timely topics of interest to clinicians and overhead throwing athletes. Several technique modifications have been reported, and these modifications may lead to improved outcomes and lower complication rates. Studies assessing sport-specific outcome measures will be necessary to provide a more critical and informative analysis of outcomes following UCL reconstruction.

Valgus stress ultrasound for medial ulnar collateral ligament injuries in athletes: is ultrasound alone enough for diagnosis?

BACKGROUND

We hypothesized that valgus stress ultrasound would be useful for both identifying medial ulnar collateral ligament (MUCL) tears and assessing the severity of the tears. Hence, we performed valgus stress ultrasound of the elbow in athletes with MUCL injuries, confirmed by magnetic resonance imaging (MRI), to determine whether ultrasound can be used as a diagnostic tool.

METHODS

Stress ultrasound and MRI data from 146 athletes with medial elbow pain were compared prospectively. MRI findings for MUCL injuries were classified into 3 levels as follows: low-grade partial tear (≤50%), high-grade partial tear (>50%), and complete tear. The degree of joint laxity on stress ultrasound was evaluated by measuring joint gapping after applying a 2.5-kg load to the wrist. Joint gapping was measured at 30° and 90° of elbow flexion for the dominant arm and nondominant arm, and the differences between the dominant and nondominant arms were determined.

RESULTS

A higher degree of MUCL injury on MRI was associated with greater joint gapping in the medial elbow on stress ultrasound. At 30° of elbow flexion, the cutoff value for complete MUCL rupture was 0.5 mm (P < .001), with a sensitivity and specificity of 88.1% and 61.5%, respectively. At 90° of elbow flexion, the cutoff value for complete MUCL rupture was 1.0 mm (P < .001), with a sensitivity and specificity of 81.0% and 66.4%, respectively.

CONCLUSION

Stress ultrasound can be used to diagnose complete MUCL tears in athletes when joint gapping is greater than 0.5 mm at 30° of elbow flexion and greater than 1 mm at 90° of elbow flexion.

Management of Ulnar Collateral Ligament Injuries in Overhead Athletes

Ulnar collateral ligament injuries of the elbow are frequent among overhead athletes. The incidence of ulnar collateral ligament reconstructions (UCLRs) in high-level players has increased dramatically over the past decade, but the optimal technique of UCLR is controversial. Surgeons need to manage the patients’ expectations appropriately when considering the mode of treatment. This article reviews current studies on the management of ulnar collateral ligament injuries, particularly in overhead athletes.

Medial elbow stability assessment after ultrasound-guided ulnar collateral ligament transection in a cadaveric model: ultrasound versus stress radiography

BACKGROUND

The ulnar collateral ligament (UCL), consisting of 3 bundles, is the primary medial restraint in the elbow. Recent research has demonstrated that ultrasound is an effective modality to evaluate the medial elbow, whereas stress radiography is standard practice in the measurement of medial elbow laxity. This study (1) compared dynamic ultrasound (US_D) with stress radiography in the evaluation of UCL insufficiency and (2) further evaluated the contribution of the anterior bundle of the UCL to medial elbow stability.

METHODS

Stress radiographs and US_D were used to obtain coronal plane measurements of the medial joint space of 16 cadaveric elbows before and after US_D-guided isolated transection of the anterior bundle of the UCL. Measurements were performed with and without a valgus stress applied to the elbows, and gapping of the ulnohumeral joint space was documented.

RESULTS

Transection of the anterior bundle of the UCL resulted in 1.5 mm and 1.7 mm of additional gapping in the ulnohumeral joint as measured with stress radiographs and US_D, respectively. No differences were recorded in the ulnohumeral gapping measurements between stress radiography and US_D.

CONCLUSIONS

The lack of difference between measurements reveals US_D is as reliable as stress radiography in evaluating the medial ulnohumeral joint space and continuity of the UCL while eliminating radiation exposure and minimizing cost of the diagnostic examination. The increase in ulnohumeral gapping with isolated transection of the anterior bundle of the UCL demonstrates its significant contribution to medial elbow stability.

Approach to Medial Elbow Pain in the Throwing Athlete

PURPOSE OF REVIEW

Injury to the ulnar collateral ligament is the most common, significant injury affecting the medial elbow of the overhead athlete. However, there are many other significant sources of pathology that should be considered. This review seeks to present a broad range of conditions that providers should consider when evaluating the overhead athlete with medial elbow pain.

RECENT FINDINGS

Recent biomechanical studies have deepened understanding of the anatomy and function of the anterior bundle of the ulnar collateral ligament germane to the overhead athlete. Orthobiologics hold potential for expanding the role of non-operative treatment for ulnar collateral ligament injuries. In addition to injury to the ulnar collateral ligament, providers should be prepared to diagnose and treat valgus extension overload, proximal olecranon stress fracture, ulnar nerve pathology, common flexor - pronator mass injury, and, in adolescents, medial epicondylar avulsion, when managing medial elbow pain in the overhead athlete.

The association of the medial joint vacuum phenomenon with ulnar collateral ligament injury in symptomatic elbows of younger athletes

OBJECTIVE

To determine the prevalence of intra-articular gas (IAG) on elbow radiography and evaluate variables, including IAG, as predictors of UCL injury.

MATERIALS AND METHODS

This IRB-approved retrospective study consisted of 241 consecutive elbow radiographic studies containing AP radiographs with valgus stress of both symptomatic and asymptomatic sides in 234 patients. The IAG, medial joint space (MJS), and MJS difference between the symptomatic and asymptomatic elbow (MJSD) were evaluated by two readers, as well as patient age, gender, sport played, and handedness. Primary outcomes included IAG on valgus stress radiographs and UCL injury, which was determined by intraoperative findings as the reference standard or MRI if surgery was not performed. Univariate analysis with Student's t, Fisher's exact, and chi-square tests were performed.

RESULTS

IAG only manifested with valgus stress and was demonstrated in 30/482 (6.2%) valgus stress radiographs in 27/234 (11.5%) patients. Overall, 21/241 (8.7%) valgus stress radiographs of the symptomatic elbow demonstrated IAG in 21 patients. A total of 128/241 (53.1%) elbow studies had evidence of UCL injury. MJS IAG (p = 0.0147) and increased MJSD (p = 0.0088) were significantly associated with UCL injury. Patient gender, age, handedness, laterality, sport played, and absolute MJS were not associated with UCL injury. MJS IAG with valgus stress demonstrates a sensitivity of 11.7% and specificity of 98.3% in detecting UCL injury for the symptomatic elbow.

CONCLUSIONS

MJS IAG infrequently manifests on valgus stress radiographs, but is specific for UCL injury in the symptomatic elbow of overhead throwing athletes. MJS IAG and increased MJSD are significantly associated with UCL injury.

Total Hip Arthroplasty in the Outpatient Setting: What You Need to Know (Part 1)

The method by which surgeons conduct outpatient total hip arthroplasty (THA) procedures has yet to be fully standardized. Careful examination of components involved in the preoperative phase of outpatient hip arthroplasty procedures may lead to improved outcomes. This article will discuss methods for implementing successful outpatient THA protocols. Specifically it reviews information regarding patient selection criteria, preoperative education, and preoperative medical optimization.

Trends in Sports-Related Elbow Ulnar Collateral Ligament Injuries

BACKGROUND

Elbow ulnar collateral ligament (UCL) injuries are common, particularly in adolescent athletes playing overhead sports. While the incidence and outcomes of surgical UCL injuries are well documented, the nonsurgical UCL injury patterns and injury management in this population are not yet known.

PURPOSE/HYPOTHESIS

The purpose of this study was to retrospectively assess the injury severity and subsequent management of UCL injuries among competitive athletes aged 11 to 22 years. We hypothesized that nonsurgical UCL injuries would occur more frequently in younger athletes compared with older athletes.

STUDY DESIGN

Descriptive epidemiological study.

METHODS

Electronic medical records (using International Classification of Diseases, 9th Revision and 10th Revision and Current Procedural Terminology codes) and keyword searches were used to identify all patients with sports-related UCL injuries between January 2000 and April 2016. A total of 136 records were included. Patients were stratified into 3 age brackets (age 11-13 years, n = 17; age 14-16 years, n = 49; age 17-22 years, n = 70). There were no prior elbow surgical interventions. The main outcome measures included the frequency and severity of UCL injuries and injury management (surgical, nonsurgical). Independent variables included age, UCL injuries per year, and sport classification.

RESULTS

There were 53 surgical and 83 nonsurgical UCL injuries. The number of nonsurgical cases increased 9-fold from 2000-2008 to 2009-2016. The UCL injuries were distributed as follows: 60 sprains, 39 partial tears, 36 ruptures, and 1 rerupture. Moreover, 7% of sprains, 51% of partial tears, and 78% of ruptures underwent UCL reconstruction. Nonsurgical management was most common in the youngest athletes (age 11-13 years, 100.0% of total injuries; age 14-16 years, 71.4% of total injuries; and age 17-22 years, 44.3% of total injuries) (P = .007). UCL injury volume was most commonly associated with javelin (odds ratio, 6.69; 95% CI, 0.72-61.62; P = .07) and baseball (odds ratio, 1.55; 95% CI, 0.69-3.51; P = .32).

CONCLUSION

Younger athletes sustained less severe UCL injuries more often than older athletes. Participation in javelin and baseball was associated with a greater likelihood of UCL injuries based on our dataset. This is the first study to provide data on the volume of nonsurgical UCL injuries among athletes in various sports.