Pre-Draft Elbow Magnetic Resonance Imaging in Major League Baseball Pitchers.

BACKGROUND: Prior to the Major League Baseball (MLB) draft, some pitchers undergo pre-draft magnetic resonance imaging (MRI). This study aimed to evaluate pre-draft elbow MRI on baseball pitchers who were entering the MLB draft to determine the presence or absence of pathology, the associations between these pathologies and UCL tears, and inter-observer reliability regarding common MRI pathology. METHODS: Pre-draft elbow MRI performed on prospective MLB pitchers between 2011-2017 were de-identified and then reviewed by two separate authors. The authors graded the MRI on several factors including presence or absence of: UCL ossification, UCL appearance (heterogeneous or not), UCL thickening (and location), UCL tear (partial vs. full thickness and location), muscle strain, flexor tendon tear, posteromedial osteophyte, sublime tubercle enthesophyte, and osseous stress reactions. RESULTS: Overall, 245 pre-draft elbow MRI were reviewed. MRI abnormalities were found in 70% (171/245) of pitchers. UCL thickening was found in 20% (50/245) of pitchers. Regarding UCL tears, 3% had a full thickness tear and 24% had a partial thickness tear. Of full thickness tears, 86% were distal and one was midsubstance. Of partial thickness tears, 41% (24/58) were distal, 12% (7/58) were midsubstance, and 47% (27/58) were proximal. Periligamentous edema was present in 36% of pitchers while 14% had a flexor pronator muscle strain. CONCLUSION: The majority (70%) of pitchers entering the MLB draft had abnormal findings on their MRI, most commonly involving changes to the UCL. Inter-observer reliability was acceptable following the definition of pathology when reading pre-draft elbow MRI on MLB prospects.

American Shoulder and Elbow Surgeons SLAP/Biceps Anchor Study Group evidence review: pathoanatomy and diagnosis in clinically significant labral injuries.

Glenoid superior biceps-labral pathology diagnosis, treatment, and outcomes are an evolving area of shoulder surgery. Historically, described as superior labrum anterior posterior (SLAP) tears, these lesions were identified as a source of pain in throwing athletes. Diagnosis and treatments applied to these SLAP lesions resulted in less than optimal outcomes in some patients and a prevailing sense of confusion. The purpose of this paper is to perform a reappraisal of the anatomy, examination, imaging, and diagnosis by the American Shoulder and Elbow Surgeons/SLAP biceps study group. We sought to capture emerging concepts and suggest a more unified approach to evaluation and identify specific needs for future research.

Application of Machine Learning Algorithms to Predict Clinically Meaningful Improvement After Arthroscopic Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Understanding specific risk profiles for each patient and their propensity to experience clinically meaningful improvement after anterior cruciate ligament reconstruction (ACLR) is important for preoperative patient counseling and management of expectations. PURPOSE: To develop machine learning algorithms to predict achievement of the minimal clinically important difference (MCID) on the International Knee Documentation Committee (IKDC) score at a minimum 2-year follow-up after ACLR. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: An ACLR registry of patients from 27 fellowship-trained sports medicine surgeons at a large academic institution was retrospectively analyzed. Thirty-six variables were tested for predictive value. The study population was randomly partitioned into training and independent testing sets using a 70:30 split. Six machine learning algorithms (stochastic gradient boosting, random forest, neural network, support vector machine, adaptive gradient boosting, and elastic-net penalized logistic regression [ENPLR]) were trained using 10-fold cross-validation 3 times and internally validated on the independent set of patients. Algorithm performance was assessed using discrimination, calibration, Brier score, and decision-curve analysis. RESULTS: A total of 442 patients, of whom 39 (8.8%) did not achieve the MCID, were included. The 5 most predictive features of achieving the MCID were body mass index ≤27.4, grade 0 medial collateral ligament examination (compared with other grades), intratunnel femoral tunnel fixation (compared with suspensory), no history of previous contralateral knee surgery, and achieving full knee extension preoperatively. The ENPLR algorithm had the best relative performance (C-statistic, 0.82; calibration intercept, 0.10; calibration slope, 1.15; Brier score, 0.068), demonstrating excellent predictive ability in the study's data set. CONCLUSION: Machine learning, specifically the ENPLR algorithm, demonstrated good performance for predicting a patient's propensity to achieve the MCID for the IKDC score after ACLR based on preoperative and intraoperative factors. The femoral tunnel fixation method was the only significant intraoperative variable. Range of motion and medial collateral ligament integrity were found to be important physical examination parameters. Increased body mass index and prior contralateral surgery were also significantly predictive of outcome.

Return to Sport After Bone-Patellar Tendon-Bone Autograft ACL Reconstruction in High School-Aged Athletes.

BACKGROUND: Anterior cruciate ligament (ACL) injuries are occurring with increasing frequency in the adolescent population. Outcomes after ACL reconstruction (ACLR) are inconsistently reported in homogeneous patient populations. PURPOSE/HYPOTHESIS: To evaluate outcomes after bone-patellar tendon-bone (BTB) autograft ACLR in competitive high school-aged athletes by examining return to sport (RTS), patient satisfaction, and reinjury rates. Our hypothesis was that RTS rates and satisfaction will be high and reinjury rates will be low. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: An institutional ACL registry was utilized to identify competitive high school-aged athletes (14-18 years old) who underwent primary ACLR using BTB autograft with a minimum 2-year follow-up. A postoperative questionnaire was administered to determine rates and types of RTS, quality of sports performance, reinjury, and satisfaction. Uni- and multivariable analyses were used to identify demographic, sport-specific, and clinical factors related to RTS. RESULTS: A total of 53 patients were included (mean ± SD age at the time of surgery, 16.6 ± 1.34 years). Mean follow-up was 3.78 ± 0.70 years (range, 2.60-4.94 years). The overall ipsilateral ACL retear rate was 7.5% (n = 4). There were 10 subsequent ACL tears to the contralateral knee (19%). Forty-four (83%) patients successfully returned to at least their prior level of sport at a mean 10.5 ± 8.7 months (range, 3-48 months). Overall satisfaction was high, with 91% of patients very satisfied with the outcome. Higher confidence levels regarding performance of the reconstructed knee were associated with increased probability of RTS on multivariate analysis. CONCLUSION: BTB autograft ACLR results in high rates of RTS and satisfaction and low rates of subsequent ipsilateral ACL injuries in competitive high school-aged athletes. Patients with higher confidence in performance of the reconstructed knee are more likely to return to at least their prior level of sport.

Nonoperative Treatment of Elbow Ulnar Collateral Ligament Injuries With and Without Platelet-Rich Plasma in Professional Baseball Players: A Comparative and Matched Cohort Analysis.

BACKGROUND: Recent studies evaluating nonoperative treatment of elbow ulnar collateral ligament (UCL) injuries augmented with platelet-rich plasma (PRP) have shown promising results. To date, no comparative studies have been performed on professional baseball players who have undergone nonoperative treatment with or without PRP injections for UCL injuries. HYPOTHESIS: Players who received PRP injections would have better outcomes than those who did not receive PRP. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The Major League Baseball (MLB) Health and Injury Tracking System identified 544 professional baseball players who were treated nonoperatively for elbow UCL injuries between 2011 and 2015. Of these, 133 received PRP injections (PRP group) before starting their nonoperative treatment program, and 411 did not (no-PRP group). Player outcomes and a Kaplan-Meier survival analysis were compared between groups. In addition, to reduce selection bias, a 1:1 matched comparison of the PRP group versus the no-PRP group was performed. Players were matched by age, position, throwing side, and league status: major (MLB) and minor (Minor League Baseball [MiLB]). A single radiologist with extensive experience in magnetic resonance imaging (MRI) interpretation of elbow injuries in elite athletes analyzed 243 MRI scans for which images were accessible for tear location and grade interpretation. RESULTS: Nonoperative treatment of UCL injuries resulted in an overall 54% rate of return to play (RTP). Players who received PRP had a significantly longer delay in return to throwing (P < .001) and RTP (P = .012). The matched cohort analysis showed that MLB and MiLB pitchers in the no-PRP group had a significantly faster return to throwing (P < .05) and the MiLB pitchers in the no-PRP group had a significantly faster RTP (P = .045). The survival analysis did not reveal significant differences between groups over time. The use of PRP, MRI grade, and tear location were not statistically significant predictors for RTP or progression to surgery. CONCLUSION: In this retrospective matched comparison of MLB and MiLB pitchers and position players treated nonoperatively for a UCL tear, PRP did not improve RTP outcomes or ligament survivorship, although there was variability with respect to PRP preparations, injection protocols, time from injury to injection, and rehabilitation programs. MRI grade and tear location also did not significantly affect RTP outcomes or progression to surgery.

Variability in Baseball Throwing Metrics During a Structured Long-Toss Program: Does One Size Fit All or Should Programs Be Individualized?

BACKGROUND: The variability of throwing metrics, particularly elbow torque and ball velocity, during structured long-toss programs is unknown. HYPOTHESES: (1) Elbow torque and ball velocity would increase as throwers progressed through a structured long-toss program and (2) intrathrower reliability would be high while interthrower reliability would be variable. STUDY DESIGN: Descriptive laboratory study. LEVEL OF EVIDENCE: Level 3. METHODS: Sixty healthy high school and collegiate pitchers participated in a structured long-toss program while wearing a validated inertial measurement unit, which measured arm slot, arm velocity, shoulder rotation, and elbow varus torque. Ball velocity was assessed by radar gun. These metrics were compared within and between all pitchers at 90, 120, 150, and 180 ft and maximum effort mound pitching. Intra- and interthrower reliabilities were calculated for each metric at every stage of the program. RESULTS: Ball velocity significantly changed at each progressive throwing distance, but elbow torque did not. Pitching from the mound did not place more torque on the elbow than long-toss throwing from 120 ft and beyond. Intrathrower reliability was excellent (intraclass correlation coefficient >0.75) throughout the progressive long-toss program, especially on the mound. Ninety-one percent of throwers had acceptable interthrower reliability (coefficient of variation <5%) for ball velocity, whereas only 79% of throwers had acceptable interthrower 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. CLINICAL RELEVANCE: Increased ball velocity does not necessarily equate to increased elbow torque in long-toss. Some individuals would likely benefit from individualized long-toss programs for rehabilitation.

Baseball Pitchers' Perceived Effort Does Not Match Actual Measured Effort During a Structured Long-Toss Throwing Program.

BACKGROUND: During rehabilitation throwing programs, baseball players are commonly asked to throw at reduced levels of effort (ie, 50% effort, 75% effort, etc) to moderate stress to healing tissues. It is currently unknown how changes in players' perceived exertion compares with changes in actual exertion during structured long-toss programs. PURPOSE: To determine whether decreased effort correlates with decreased throwing metrics, whether metrics decrease proportionally with reductions in perceived effort, and to quantify intrathrower variability. STUDY DESIGN: Descriptive laboratory study. METHODS: Sixty male high school and collegiate baseball pitchers participated in a structured throwing program. A motusBASEBALL sleeve was worn by all players, which measured elbow varus torque, arm velocity, arm slot, and shoulder rotation. Ball velocity was measured with a radar gun. Each pitcher threw 5 throws a distance of 120 ft with 3 efforts: maximum effort, 75% effort, and 50% effort. Throwing metrics were compared among the 3 levels of effort to see if each 25% decrease resulted in proportional decreases in elbow varus torque and ball velocity. Intrathrower variability was determined for each throwing metric at each degree of effort. RESULTS: All throwing metrics decreased as players decreased their perceived effort (P < .001). However, these observed decreases were much smaller in magnitude than the decreases in perceived effort. During the 75% effort throws, elbow varus torque was only reduced to 93% of maximum and velocity dropped to 86% of maximum. Similarly, for the 50% effort throws, elbow varus torque remained 87% of max effort torque, while velocity remained 78% of max. Intrathrower reliability was considered excellent for most metrics (intraclass correlation coefficient, >0.75). CONCLUSION: For every 25% decrease in perceived effort, elbow varus torque only decreased 7% and velocity only decreased 11%. Thus, when players throw at what they perceive to be reduced effort, their actual throwing metrics do not decrease at the same rate as their perceived exertion. CLINICAL RELEVANCE: Measured effort decreased with decreasing perceived effort, but these were not proportional. This has significant implications for physical therapists, physicians, trainers, coaches, and athletes to understand and monitor elbow stress during the rehabilitation process.

Getting Hit by Pitch in Professional Baseball: Analysis of Injury Patterns, Risk Factors, Concussions, and Days Missed for Batters.

BACKGROUND: Although batters are frequently hit by pitch (HBP) in baseball, the effect of HBP injuries remains undefined in the literature. PURPOSE: To determine the effect of HBP injuries in terms of time out of play, injury patterns resulting in the greatest time out of play, and the value of protective gear such as helmets and elbow pads. STUDY DESIGN: Descriptive laboratory study. METHODS: Based on the Major League Baseball (MLB) Health and Injury Tracking System, all injuries to batters HBP during the 2011-2015 MLB and Minor League Baseball (MiLB) seasons were identified and analyzed. Video analysis was performed on all HBP events from the 2015 MLB season. Multivariate stepwise regression analysis was utilized to determine the predictive capacity of multiple variables (velocity, pitch type, location, etc) on injury status and severity. RESULTS: A total of 2920 HBP injuries resulted in 24,624 days missed (DM) over the 5 seasons. MLB HBP injuries occurred at a rate of 1 per 2554 plate appearances (1 per 9780 pitches thrown). Mean DM per injury were 8.4 (11.7 for MLB vs 8.0 for MiLB, P < .001). Surgery was required for 3.1% of MLB injuries and 1.2% of MiLB injuries ( P = .005). The most common body regions injured were the hand/fingers (n = 638, 21.8%), head/face (n = 497, 17.0%), and elbow (n = 440, 15.7%), and there were 146 (5.0%) concussions. Injury rates and mean DM correlated with velocity in a near linear fashion. Players hit in the head/face (odds ratio, 28.7) or distal upper extremity (odds ratio, 6.4) were more likely to be injured than players HBP in other locations. Players with an unprotected elbow missed 1.7 more days (95% CI, -4.1 to 7.6) than those with an elbow protector ( P = .554) when injured after being HBP. CONCLUSION/CLINICAL RELEVANCE: Although HBP injuries occur infrequently in the course of normal play, they collectively represent a significant source of time out of play. The most common body regions injured include the hands/fingers and head/face, and batters hit in these locations are significantly more likely to be injured. After contusions, concussions were the most common injury diagnosis.

Epidemiology of ulnar collateral ligament reconstruction in Major and Minor League Baseball pitchers: comprehensive report of 1429 cases.

BACKGROUND: The primary purpose of this work is to provide an epidemiologic report on every known ulnar collateral ligament (UCL) reconstruction performed in professional baseball with a special focus on outcomes and survivorship. METHODS: Three resources, including the Major League Baseball (MLB) injury tracking system, were combined and cross-referenced to identify all known professional baseball pitchers who had ever undergone UCL reconstruction from 1974 to 2016. Variables analyzed included injury date, surgery date, return to play rates, time out of play, and revision status. Trends over time were analyzed collectively and by level of play at the time of surgery. A minimum of 2 years of follow-up was required for return to play analysis. RESULTS: We identified 1429 UCL reconstructions. The annual rate of primary and revision UCL reconstructions rose significantly (P < .001). Most players (83.7%) returned to any level of play at a mean of 435 days, whereas 72.8% (P < .001) returned to their prior level at a mean of 506 days. Major League Baseball players were more likely than Minor League Baseball players to return to any level (94.6% vs. 79.0%, P < .001) and their prior level of performance (80.0% vs. 69.1%, P = .04). The mean overall survivorship free from revision and still playing was 3.8 years (3.9 for primary vs. 2.9 for revisions, P = .018). The revision rate was 6.7% and was higher for Major League Baseball (9.4%) vs. Minor League Baseball (5.2%, P = .004). CONCLUSIONS: This study represents the most robust epidemiologic report of UCL reconstruction in baseball to date, and a multitude of novel findings are reported.

Effect of Predraft Ulnar Collateral Ligament Reconstruction on Future Performance in Professional Baseball: A Matched Cohort Comparison.

BACKGROUND: In recent years, there has been a dramatic rise in the annual number of ulnar collateral ligament (UCL) reconstructions performed in amateur baseball pitchers. Accordingly, increasing numbers of players are entering professional baseball having already undergone the procedure; however, the effect of prior UCL reconstruction on future success remains unknown. PURPOSE: (1) To provide an epidemiologic report on baseball players who undergo UCL reconstruction before being selected in the Major League Baseball (MLB) Draft, (2) to define the outcomes in terms of statistical performance, and (3) to compare these results with those of matched controls (ie, non-UCL reconstruction). STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The MLB Amateur Draft Database was queried to identify all drafted pitchers who underwent UCL reconstruction before being drafted. For each pitcher drafted from 2005 to 2014 with prior UCL reconstruction, 3 healthy controls with no history of elbow surgery were randomly identified for matched analysis. A number of demographic and performance comparisons were made between these groups. RESULTS: A total of 345 pitchers met inclusion criteria. The annual number of pitchers undergoing predraft UCL reconstructions rose steadily from 2005 to 2016 ( P < .001). For matched control analysis, 252 pitchers with a UCL reconstruction and a minimum 2-year follow-up (drafted between 2005 and 2014) were matched to 756 controls (non-UCL reconstruction). As compared with the non-UCL reconstruction group, pitchers who underwent predraft UCL reconstruction reached the MLB level with greater frequency (20% vs 12%, P = .003), and their MLB statistical performances were similar for all measures. Compared with all other pitchers drafted during that period, players who had a predraft UCL reconstruction demonstrated an increased likelihood of reaching progressive levels of play (Full Season A, AA, and MLB) within a given time frame ( P < .05 for all). CONCLUSION: The number of UCL reconstructions performed in amateur baseball players before the draft increased year over year for the entire study period. Professional pitchers who underwent UCL reconstruction as amateurs appear to perform at least as well as, if not better than, matched controls without elbow surgery.

Following ulnar collateral ligament reconstruction, professional baseball position players return to play faster than pitchers, but catchers return less frequently.

BACKGROUND: Although much as been done to characterize trends of medial ulnar collateral ligament (UCL) reconstruction in pitchers, outcomes in position players (PPs) (non-pitchers) remain undefined in the current literature. METHODS: Three resources were combined to identify all known Major League Baseball and Minor League Baseball (MiLB) PPs who have ever undergone UCL reconstruction. A multitude of player and surgical variables were included. Trends over time were analyzed collectively, based on level of play, revision status (primary vs revision), and position. Additional comparisons were made with a known cohort of professional baseball pitchers having undergone UCL reconstruction. RESULTS: We identified 168 UCL reconstructions in professional PPs. The annual rate of primary UCL reconstruction rose significantly from 1984 to 2015 (P < .001), and the proportion of cases performed in MiLB PPs (vs Major League Baseball PPs) increased steadily (P < .001). Of PPs, 75.5% returned to play at any level at a mean of 342 days. Catchers demonstrated the lowest return-to-play (RTP) rate (58.6%) compared with infielders (75.6%) and outfielders (88.9%). The overall revision rate was low, at 4.8%. Compared with pitchers, PPs demonstrated a lower rate of RTP (75.5% for PPs vs 83.7% for pitchers, P = .040) but shorter RTP times for those able to return (342 days for PPs vs 435 days for pitchers, P < .001). CONCLUSIONS: The incidence of UCL reconstruction in PPs continues to rise, a trend that is significantly more pronounced at the MiLB level. Although PPs (particularly catchers) are less likely to return to professional baseball compared with pitchers, those who are able to RTP do so more rapidly.

Changes in Lower Extremity Kinematics and Temporal Parameters of Adolescent Baseball Pitchers During an Extended Pitching Bout.

BACKGROUND: Few studies have investigated detailed 3-dimensional lower extremity kinematics during baseball pitching in adolescent athletes during extended play. Changes in these parameters may affect performance outcomes. PURPOSE: To investigate whether adolescent baseball pitchers experience changes in lower extremity kinematics and event timing during a simulated game-length pitching bout. STUDY DESIGN: Descriptive laboratory study. METHODS: Twelve male adolescent pitchers (aged 14-16 years) threw 6 sets of 15 fastball pitches from an artificial pitching mound to a target at regulation distance. Joint angles and angular velocities at the hip, knee, and ankle of both legs were collected throughout the phases of the pitching cycle as well as stride length, pelvis orientation, pitch duration, timing of foot contact and ball release, ball speed, and pitching accuracy. Paired t tests ( P < .05) were used to compare the dependent variables between the last 5 pitches of the second (baseline) and sixth (final) sets. RESULTS: During the stride phase, decreased maximum angular excursions for hip extension (baseline: 14.7° ± 9.8°; final: 11.6° ± 10.3°; P < .05) and ankle plantar flexion (baseline: 30.2° ± 14.5°; final: 24.2° ± 15.3°; P < .05) as well as maximum angular velocity for knee extension (baseline: 144.9 ± 63.3 deg·s-1; final: 121.7 ± 62.0 deg·s-1; P < .05) were observed between sets in the trailing leg. At foot contact, pitchers had decreased hip flexion (baseline: 69.5° ± 10.1°; final: 66.5° ± 11.8°; P < .05) and increased hip abduction (baseline: 20.7° ± 8.9°; final: 25.4° ± 6.0°; P < .05) in the leading leg in the final set. Compared with the baseline set, ball speed significantly decreased in the final set (29.5 ± 2.5 m·s-1 vs 28.3 ± 2.5 m·s-1, respectively; P < .05). CONCLUSION: Kinematic changes and decreased ball speeds observed in the final set suggest that adolescent pitchers are unable to maintain lower extremity kinematics and performance as a result of extended play. CLINICAL RELEVANCE: The results from this study may warrant further investigation into how altered lower extremity kinematics may affect trunk and upper extremity function, performance, and risk of injuries during pitching in adolescent athletes, particularly during actual game play.

Developing and Implementing Major League Baseball's Health and Injury Tracking System.

In 2010, Major League Baseball and the Major League Baseball Players Association reached an agreement regarding the development and implementation of an electronic medical record system and a new league-wide injury surveillance system. The systems were developed to create a more efficient method to track medical histories of players longitudinally as they move across Major and Minor league affiliates, as well as to identify and monitor injury trends in the sport, identify areas of specific concern, and conduct epidemiologic research to better optimize player health and safety. The resulting injury surveillance system, the Health and Injury Tracking System (HITS), is a robust system that includes all players from the both the Major and Minor Leagues. HITS also allows for data linkage with other player- and game-level data to inform the development of injury prevention policies and programs. In the present article, we document the development and implementation of HITS; describe its utility for epidemiologic research; illustrate the potential analytic strength of the surveillance system and its ability to inform policy change; and note the potential for this new surveillance system to advance the field of sports injury epidemiology.

Platelet-rich plasma for the treatment of lateral epicondylitis: sonographic assessment of tendon morphology and vascularity (pilot study).

OBJECTIVE: To investigate the efficacy of using contrast-enhanced ultrasound to assess the relationship of altered vascularity and tendon morphology following injection of platelet-rich plasma (PRP) for lateral epicondylitis. MATERIALS AND METHODS: This study prospectively evaluated six patients who had a baseline ultrasound confirming tendinosis of the common extensor tendon. Patients received a single 3-ml PRP injection under ultrasound guidance. Grayscale images of the injected elbow were obtained at baseline and were repeated at 1 and 6 months after injection. DEFINITY® contrast was also injected after by 2 sets of wrist-extension exercises in order to obtain contrast-enhanced images of the elbow. Qualitative and quantitative analyses of the level of enhancement to the regions of interest were performed using off-line quantitative analysis software. RESULTS: All patients had either moderate or severe common extensor tendinosis as determined on clinical examination and baseline imaging. Five patients demonstrated improved tendon morphology using ultrasound imaging 6 months after PRP injection (one patient was lost to follow-up). At baseline, there was evidence of increased vascularity at the myotendinous junction (MT) of the common extensor tendon when compared to its footprint (FP). There was a trend towards no change in FP vascularity between baseline and 6 months (p = 0.062) and between 1 and 6 months (p = 0.288). There was a trend for increased vascularity to the MT region from baseline to 6 months (p = 0.433) and from 1 to 6 months (p = 0.783). CONCLUSIONS: Contrast-enhanced ultrasound provides a sensitive method the display alterations in vascularity in the common extensor tendon of the elbow. PRP therapy for lateral epicondylitis can improve extensor tendon morphology. Corresponding increased extensor tendon FP vascularity, however, was not seen. There is a trend for increased vascularity at the MT up to 6 months following PRP injection, based on limited pilot data.

Contrast-enhanced ultrasound characterization of the vascularity of the repaired rotator cuff tendon: short-term and intermediate-term follow-up.

BACKGROUND: The objectives of this study were to characterize and compare the vascularity of arthroscopically repaired rotator cuff tendons at short-term and intermediate-term follow-up. MATERIALS AND METHODS: Nineteen patients who underwent arthroscopic rotator cuff repair were prospectively monitored for an average of 21.2 months. Initial baseline, grayscale ultrasound images of the operated-on shoulder were obtained on all patients at 3 months and at a minimum of 10 months postoperatively. Perflutren-lipid microsphere contrast (DEFINITY, Lantheus Medical Imaging, North Billerica, MA, USA) was injected after baseline grayscale images and after exercise to obtain contrast-enhanced images of the repair. Three regions of interest--supraspinatus tendon, peribursal tissue, and bone anchor site--were evaluated before and after rotator cuff-specific exercises. RESULTS: The peribursal tissue demonstrated the greatest blood flow, followed by the bone anchor site and tendon, in pre-exercise and postexercise states. Significantly less blood flow was observed in all regions of interest before exercise (P < .05) and only at the bone anchor site after exercise (P < .001) at latest follow-up compared with the 3-month values. Intratendinous blood flow remained relatively low at both evaluation points after surgical repair. CONCLUSION: Preliminary findings suggest that the peribursal tissue and bone anchor site are the main conduits of blood flow for the rotator cuff tendon after arthroscopic repair, with the supraspinatus tendon being relatively avascular. Blood flow of the repaired rotator cuff tendon decreases with time. Furthermore, exercise significantly enhances blood flow to the repaired rotator cuff.

Contrast-enhanced sonographic characterization of the vascularity of the repaired rotator cuff: utility of maximum intensity projection imaging.

OBJECTIVES: To characterize the distribution of vascularity of the postoperative rotator cuff tendon using a maximum intensity projection technique after contrast-enhanced sonography. METHODS: We retrospectively evaluated image data on 23 patients (11 male and 12 female) with intact rotator cuff repairs who had previously undergone contrast-enhanced sonography of their shoulders using lipid microspheres before and after a standardized exercise protocol. The patients were on average 3 months out from their surgery. Using offline image analysis software, a maximum intensity projection image was obtained for each patient, reflecting the regional vascular distribution within the repair and adjacent soft tissue. Subjective analysis was performed in 4 regions of interest: peribursal, articular medial, articular lateral, and suture anchor, independently by 2 musculoskeletal radiologists using a semiquantitative scale ranging from 0 to 4 for each region (0, no enhancement; 1, 1%-25% enhancement; 2, 26%-50%; 3, 51%-75%; and 4, 76%-100%). A combined vascularity score (0-8) was produced for each region and formed the basis for the subjective analysis. RESULTS: Using a Mann-Whitney nonparametric test, the data showed significantly higher regional enhancement in the peribursal and suture anchor regions compared to the tendon (P < .001). Exercise resulted in a statistically significant increase in the extent of enhancement in all regions (P < .002). Inter-rater reliability analysis using a weighted κ statistic showed strong agreement (0.63-0.64) for the suture anchor site and moderate agreement for the others (peribursal, 0.35-0.39; articular medial, 0.45-0.55; and articular lateral 0.32-0.33). CONCLUSIONS: The maximum intensity projection technique after contrast-enhanced sonography provides a topographic map of rotator cuff vascularity; the latter has been implicated as an important factor in promoting bone-tendon healing. Approximately 3 months after rotator cuff repair, the suture anchor and peribursal regions showed the most robust vascularity. Maximum intensity projection imaging further establishes that there is a global increase in vascular response at the repair site after exercise.

Symptomatic glenoid loosening complicating total shoulder arthroplasty.

Glenoid component loosening is one of the most common causes of failed total shoulder arthroplasty. Previous reports indicate that it is desirable to reimplant the glenoid component during revision shoulder arthroplasty. The purpose of our study was to retrospectively evaluate the satisfaction of patients undergoing glenoid revision (reimplantation or resection) following total shoulder replacement specifically for symptomatic glenoid loosening. Twenty-eight shoulders that developed symptomatic glenoid loosening following primary total shoulder arthroplasty were included in the study. Patients were retrospectively evaluated at a minimum of 2 years postoperatively. Patients either underwent resection followed by reimplantation of the glenoid component (13) or resection of the component with or without bone grafting (15). Each patient was evaluated with the UCLA Shoulder Scale and the Constant-Murley Shoulder Assessment. There were seven excellent, 13 good, five fair and three poor results on the UCLA score. Functional outcome scores trended higher in the reimplantation group but were not statistically significant. Both groups reported equal pain relief and satisfaction. Five out of 15 patients underwent arthroscopic resection of the glenoid, and these patients scored as well on the UCLA and Constant scores as the reimplantation group. When symptomatic glenoid loosening is the indication for revision total shoulder replacement, patients tend to achieve good to excellent results. Though functional scores were slightly higher in the reimplantation group, satisfaction was equally high in both groups. Resection, when indicated, should be performed arthroscopically as this improved functional outcome in our series.

Vascularity of the supraspinatus tendon three months after repair: characterization using contrast-enhanced ultrasound.

BACKGROUND: There has been limited in-vivo assessment of rotator cuff vascularity following repair. This study aims to characterize the vascularity of the shoulder 3 months following supraspinatus tendon repair. METHODS: Twenty-nine patients (average age, 61.4 years) underwent Perflutren lipid microsphere contrast-enhanced shoulder ultrasound examinations 3 months after arthroscopic rotator cuff repair. Each shoulder was scanned at rest and following exercise using linear phased array 9-MHz transducer optimized to detect the contrast agent. Blood flow was quantified off-line using ultrasound imaging quantification and analysis software (QLAB, Philips, Andover, MA). Peak enhancement (vascular volume) and rate of rise (perfusion) were determined for 3 regions of interest: peribursal area, supraspinatus tendon, and anchor site. RESULTS: Peak enhancement and rate of rise were greatest in the peribursal soft tissue and anchor site. Resting peak enhancement and rate of rise were significantly lower within the tendon compared to the other 2 regions (P < .001). Exercise resulted in increased enhancement and rate-of-rise to all 3 regions, but had a significant predilection towards increasing vascular volume within the peri-bursal region (P = .026). CONCLUSION: At 3 months following repair, the majority of blood flow to the repair is derived from the peribursal soft tissues and the anchor site. The tendon, particularly those with a defect at 3 months, is relatively avascular. Though limited by inclusion of only a single time point, this study introduces a new technique to quantify vascularity following supraspinatus repairs and suggests that the surrounding vascular milieu may play a role in tendon healing. LEVEL OF EVIDENCE: Basic Science.

Deep vein thrombosis after reconstructive shoulder arthroplasty: a prospective observational study.

This clinical study was performed to document the prevalence of deep vein thrombosis (DVT) after prosthetic shoulder replacement surgery. We prospectively followed 100 consecutive shoulder arthroplasty procedures (total shoulder replacement in 73 and hemiarthroplasty in 27) in 44 male and 56 female patients for 12 weeks (mean age, 67 years; range, 17-88 years). Risk factors for venous thromboembolic disease were assessed preoperatively and postoperatively. A 4-limb surveillance color flow Doppler ultrasound was performed at 2 days (100 patients) and 12 weeks (50 patients randomly selected) after surgery, and the presence and location of DVT were recorded. Postoperative symptomatic or fatal pulmonary emboli (PE) were also recorded. The overall prevalence of DVT was 13.0%, consisting of 13 DVTs in 12 patients. These included 6 ipsilateral and no contralateral upper extremity DVTs and 5 ipsilateral and 2 contralateral lower extremity DVTs. The prevalence of DVT was 10.0% (10/100) at day 2 after surgery and 6.0% (3/50) at week 12 after surgery. The incidence of symptomatic nonfatal PE was 2.0% (2/100), and that of fatal PE was 1.0% (1/100). Risk factors associated with venous thromboembolic disease did not reach statistical significance because of the small study population sample size. At our institution, the prevalence of DVT after reconstructive shoulder arthroplasty was 13.0%, a rate comparable to that after hip arthroplasty (10.3%) but lower than that after knee arthroplasty (27.2%). Shoulder arthroplasty surgeons should be aware of the potential risk of perioperative thromboembolic complications in both the acute and subacute postoperative periods.

Proximal tibia fracture after anterior cruciate ligament reconstruction using bone-patellar tendon-bone autograft: a case report.

The optimal operative management of anterior cruciate ligament (ACL) injury continues to be debated. Many complications can occur, but fracture is often not routinely discussed. We present a complex intra-articular tibia fracture in a patient who had an autologous, ipsilateral bone-patellar-bone ACL reconstruction. While still advocating early, aggressive physical therapy, this case reminds us of the inherent susceptibility to injury in the immediate post-operative period.