Real-world status of treatment for lymphoid neoplasms developed during the course of myeloproliferative neoplasms in Japan

OBJECTIVES

Patients with myeloproliferative neoplasms (MPNs) are at higher risk of developing secondary malignancies. In this study, we focused on patients with MPNs that complicated lymphoid neoplasms. To analyze the real-world status of lymphoid neoplasm treatment in patients with pre-existing MPNs in Japan, we conducted a multicenter retrospective study.

METHODS

Questionnaires were sent to collect the data on patients who were first diagnosed with either polycythemia vera, essential thrombocythemia or myelofibrosis and who later were complicated with lymphoid neoplasms defined as malignant lymphoma, multiple myeloma, or chronic lymphocytic leukemia/small cell lymphoma.

RESULTS

Twenty-four patients with MPNs complicated by lymphoid neoplasms were enrolled (polycythemia vera, n = 8; essential thrombocythemia, n = 14; and primary myelofibrosis, n = 2). Among these, diffuse large B-cell lymphoma (DLBCL) was the most frequently observed (n = 13, 54.1%). Twelve (92.3%) of the patients with DLBCL received conventional chemotherapy. Among these 12 patients, regarding cytoreductive therapy for MPNs, 8 patients stopped treatment, one continued treatment, and two received a reduced dose. Consequently, most patients were able to receive conventional chemotherapy for DLBCL with a slightly higher dose of granulocyte colony-stimulating factor support than usual without worse outcomes. All 3 patients with multiple myeloma received a standard dose of chemotherapy.

CONCLUSION

Our data indicate that if aggressive lymphoid neoplasms develop during the course of treatment in patients with MPNs, it is acceptable to prioritize chemotherapy for lymphoma.

Muon spin relaxation and emergence of disorder-induced unconventional dynamic magnetic fluctuations in Dy2Zr2O7

The disordered pyrochlore oxide Dy2Zr2O7shows the signatures of field-induced spin freezing with remnant zero-point spin-ice entropy at 5 kOe magnetic field. We have performed zero-field and longitudinal field Muon spin relaxation (µSR) studies on Dy2Zr2O7. Our zero field studies reveal the absence of both long-range ordering and spin freezing down to 62 mK. TheµSR relaxation rate exhibits a temperature-independent plateau below 4 K, indicating a dynamic ground state of fluctuating spins similar to the well-known spin ice system Dy2Ti2O7. The low-temperature spin fluctuations persist in the longitudinal field of 20 kOe as well and show unusual field dependence of the relaxation rate, which is uncommon for a spin-liquid system. Our results, combined with the previous studies do not show any evidence of spin ice or spin glass ground state, rather point to a disorder-induced dynamic magnetic ground state in the Dy2Zr2O7material.

Prevalence of osteochondritis dissecans of the capitellum in elementary school baseball players based on ultrasonographic screening: a 15-year overview in Tokushima, Japan

Background

Although several operative procedures have evolved for capitellar osteochondritis dissecans (OCD), the best outcome is achieved by early detection and conservative treatment. The objective of this study was to clarify changes in the prevalence of capitellar OCD in young baseball players over a long-term period based on consistent criteria in Tokushima, Japan between 2006 and 2020.

Methods

The number of players who underwent screening and the discovery rate of capitellar OCD during the study period were investigated. School grade and radiographic stage were also evaluated.

Results

The confirmation rate was significantly higher when ultrasonographic screening was performed than when screening was based on physical findings (65.8% vs. 1.9%, P < .001). The overall incidence of OCD in elementary school players based on ultrasonographic screening was 1.4% during the 10-year study period. Twenty-one (10.8%) of the 195 players identified to have OCD had experienced lateral elbow pain. When classified radiographically, the lesion was stage I in 73.3% of cases, stage II in 24.1%, and stage III in 2.6%. No cases of OCD were diagnosed before the fourth grade. The prevalence rates increased gradually from the fourth grade to the sixth grade.

Conclusion

Ultrasonographic screening could be more effective for detecting capitellar OCD than screening based on physical findings. The overall prevalence of OCD among elementary school players was 1.4% over 10 years. The prevalence rates increased gradually from the fourth grade onwards.

Preoperative Computed Tomography of the Right Gastroepiploic Artery for Coronary Artery Bypass Grafting

BACKGROUND

Grafting the right gastroepiploic artery (GEA) to the right coronary artery (RCA) is effective, but preoperative evaluation of arterial conduit availability has not been established. By comparing the midterm graft results, we aimed to assess the efficacy of preoperative evaluation of the GEA using computed tomography (CT).Methods and Results: We retrospectively examined patients who underwent isolated coronary artery bypass grafting surgery between April 2010 and December 2020, and those whose GEA was grafted to the RCA were selected: 55 patients were included in the study analysis. Postoperative evaluations were performed during the early phase, 1 year postoperatively, and at follow-up evaluations. The outer diameter of the proximal GEA was compared with the midterm graft patency grade on CT and patients were classified as Functional (Grade A) or Dysfunctional (Grades O or B). The proximal GEA outer diameters were significantly different between the Functional and Dysfunctional groups (P<0.001). Furthermore, multivariate Cox regression analysis revealed that this diameter was an independent predictor of graft functionality (P<0.001). Patients with outer proximal diameters larger than the cutoff value had superior graft results at 3 years postoperatively. The rate of freedom from a dysfunctional graft at 3 years postoperatively was 95.5% and 45.5% for the Larger and Smaller diameter subgroups, respectively (P<0.001).

CONCLUSIONS

Preoperative evaluation of the outer diameter of the proximal GEA, excluding calcified GEA, using CT is a minimally invasive and useful method, and may improve midterm results of in-situ GEA grafting, even in severe stenotic lesions.

Riboflavin compounds show NAD(P)H dependent quinone oxidoreductase-like quinone reducing activity

NAD(P)H-dependent quinone oxidoreductase (NQO) is an essential enzyme in living organisms and cells protecting them from oxidative stress. NQO reduces coenzyme Q (CoQ) using NAD(P)H as an electron donor. In the present study, we searched for coenzyme Q10 reducing activity from fractions of gel filtration-fractionated rat liver homogenate. In addition to the large-molecular-weight fraction containing NQO, CoQ10 reducing activity was also detected in a low-molecular-weight fraction. Furthermore, dicumarol, a conventional inhibitor of NQO1 (DT diaphorase), did not inhibit the reduction but quercetin did, suggesting that the activity was not due to NQO1. After further purification, the NADH-dependent CoQ10-reducing compound was identified as riboflavin. Riboflavin is an active substituent of other flavin compounds such as FAD and FMN. These flavin compounds also reduced not only CoQ homologues but also vitamin K homologues in the presence of NADH. The mechanism was speculated to work as follows: NADH reduces flavin compounds to the corresponding reduced forms, and subsequently, the reduced flavin compounds immediately reduce bio-quinones. Furthermore, the flavin-NADH system reduces CoQ10 bound with saposin B, which is believed to function as a CoQ transfer protein in vivo. This flavin-dependent CoQ10 reduction, therefore, may function in aqueous phases such as the cell cytosol and bodily fluids.

Metric fixed point theory and partial impredicativity

We show that the Priess-Crampe & Ribenboim fixed point theorem is provable in [Formula: see text]. Furthermore, we show that Caristi's fixed point theorem for both Baire and Borel functions is equivalent to the transfinite leftmost path principle, which falls strictly between [Formula: see text] and [Formula: see text]. We also exhibit several weakenings of Caristi's theorem that are equivalent to [Formula: see text] and to [Formula: see text]. This article is part of the theme issue 'Modern perspectives in Proof Theory'.

Fostamatinib for the treatment of Japanese patients with primary immune thrombocytopenia: A phase 3, placebo-controlled, double-blind, parallel-group study

Fostamatinib, a spleen tyrosine kinase inhibitor, has been approved for the treatment of chronic primary immune thrombocytopenia (ITP) in the United States, Canada and some European countries. We conducted a phase 3, placebo-controlled, double-blind, parallel-group study to evaluate the efficacy and safety of fostamatinib in Japanese patients with primary ITP. Thirty-four patients were randomised to fostamatinib (n = 22) or placebo (n = 12) at 100-150 mg twice a day for 24 weeks. Stable responses (platelet ≥50 000/μl at ≥4 of the 6 visits from weeks 14 to 24) were observed in eight (36%) patients on fostamatinib and in none of the patients on placebo (p = 0.030). Overall responses (platelet ≥50 000/μl at ≥1 of the 6 visits from weeks 2 to 12) were seen in 10 (45%) patients on fostamatinib and in none of the patients on placebo (p = 0.006). Patients on fostamatinib required rescue medication less often and experienced fewer bleeding symptoms than patients on placebo. Adverse events observed were mild or moderate and were manageable. No new safety signals were identified in Japanese patients with ITP.

Between-day reliability and minimum detectable change of the Conventional Gait Model 2 and Plug-in Gait Model during running

BACKGROUND

The Plug-in Gait model (PiG) is commonly used in 3D motion analysis but has limited reliability. Although an improved version of PiG has been developed, called the Conventional Gait Model 2 (CGM2), there is limited evidence on its between-day reliability for running.

RESEARCH QUESTION

What is the between-day intraclass correlation coefficient (ICC3,k) and minimum detectable change (MDC) of lower limb kinematics and kinetics for CGM2 during running and does reliability differ between CGM2 and PiG.

METHODS

Twenty-three healthy participants performed running at a comfortable speed in two identical test sessions at least 5 days apart. Lower limb kinematic and kinetic data in the three planes of motion were calculated using CGM2 and PiG. The ICC and MDC were calculated for the kinematic and kinetic parameters at initial contact and peak during the stance phase of running.

RESULTS

CGM2 kinematics showed good-to-excellent reliability (ICC: 0.75-0.93), except for hip extension and ankle internal rotation, and less than 5° MDC (1.8°-4.9°) of the coronal and sagittal planes, except for hip extension. PiG showed poor-to-moderate reliability (ICC: -0.15 to 0.72) in the coronal and transverse planes and greater than 5° MDC (5.0°-21.8°), except for knee extension, adduction, and ankle dorsiflexion. CGM2 showed good-to-excellent reliability for peak kinetics (ICC: 0.75-0.97), except for hip internal rotation and knee extension. The ICC and MDC were higher for CGM2 than PiG, with significant differences in the coronal plane of the hip and knee joints and transverse plane of the hip joint in kinematics and in the sagittal and coronal plane of the hip and knee joints in kinetics.

SIGNIFICANCE

The between-day reliability of CGM2 was mostly good to excellent for lower limb kinematics and kinetics during running. We believe that CGM2 can more accurately assess kinematic differences between the coronal and transverse planes than the PiG.

Development of adjusted nuclear data library for fast reactor application

In Japan, development of adjusted nuclear data library for fast rector application based on the cross-section adjustment method has been conducted since the early 1990s. The adjusted library is called the unified cross-section set, which is an ABBN-type group constant set with 70-group energy structure. The first version was developed in 1991 and is called ADJ91. After that, ADJ98, ADJ2000, ADJ2000R, and ADJ2010 were constantly developed. For instance, ADJ2010 was developed based on JENDL-4.0, which provides covariance data needed to apply the cross-section adjustment method, by using 488 integral experimental data acquired in typical fast reactor systems. ADJ2010 has been used as the standard cross-section set for nuclear design in the fast reactor cycle technology development project (FaCT) and the succeeding fast reactor projects. In parallel, the integral experimental data were further expanded to improve the design prediction accuracy of the core loaded with MA and/or degraded Pu. Using the additional integral experimental data, development of the next version of ADJ2017 was started in 2017. In 2022, the latest unified cross-section set AJD2017R was developed based on JENDL-4.0 by using 619 integral experimental data. An overview of the latest version with a review of previous ones will be shown.

On the other hand, the latest Japanese evaluated nuclear data library JENDL-5 was released at the end of 2021. In the development of JENDL-5, some of the integral experimental data used in ADJ2017R were explicitly utilized in the nuclear data evaluation. However, this is not reflected in the covariance data. This situation needs to be considered when developing a next version of the unified cross-section set based on JENDL-5. Preliminary adjustment calculation based on JENDL-5 is performed using C/E (calculation/experiment) values simply evaluated by a sensitivity analysis. The preliminary result of the JENDL-5-based adjustment will be also discussed.

Application of the extended bias factor method for highly reliable benchmark suite

It was tried to get useful information feedback on cross section and covariance by application of extended bias factor method with experimental benchmarks’ C/E, sensitivity coefficient and covariance data. As a result, it was succeeded to distinguish “the case unrecommended by specialists” as outlier case. And it was succeeded to get the hints that there is room for improvement in cross section or covariance of some nuclides by investigating outlier cases judged as recommended case by specialists.

COVID-19 and Thrombosis: Clinical Aspects

In coronavirus disease 2019 (COVID-19), thrombus formation is related to the pathogenesis of acute respiratory distress syndrome (ARDS) and the progression of clinical symptoms. Severe damage to vascular endothelial cells and the associated cytokine storm after SARS-CoV-2 infection cause thrombogenesis and contribute to the development of more severe and unique thromboses compared to other infectious diseases. Thromboses occur more often in critically ill patients. In addition to pulmonary thromboembolism (PE) and deep vein thrombosis, acute myocardial infarction, peripheral arterial thrombosis, and aortic thrombosis have also been reported. In PE, thrombi develop in both pulmonary arteries and alveolar capillaries. These, together with intraalveolar fibrin deposition, interfere with effective gaseous exchange in the lungs and exacerbate the clinical symptoms of ARDS in patients with COVID-19. Pharmacological thromboprophylaxis is recommended for all hospitalized patients to prevent both thrombosis and aggravation of ARDS, and other organ failures. Although the pediatric population is mostly asymptomatic or develops mild disease after SARS-CoV-2 infection, a new inflammatory disorder affecting the cardiovascular system, multisystem inflammatory syndrome in children (MIS-C), has been reported. Similar to Kawasaki disease, acute myocarditis, coronary vasculitis, and aneurysms are typically seen in MISC, although these two are now considered distinct entities. A similar acute myocarditis is also observed in young male adults, in which a hyperinflammatory state after SARS-CoV-2 infection seems to be involved. Several side effects following vaccination against COVID-19 have been reported, including vaccine-induced immune thrombotic thrombocytopenia and acute myocarditis. Although these could be serious and life-threatening, the cases are very rare, thus, the benefits of immunization still outweigh the risks.

Transformed Mycosis Fungoides with a Cytotoxic T-Cell Phenotype

Mycosis fungoides (MF) is a cutaneous T-cell lymphoma and occasionally undergo large cell transformation (transformed MF, TMF), resulting in a poorer clinical outcome. We describe a case of TMF with an immunophenotypic shift. MF showed the CD4 + CD8- T-cell phenotype, while TMF exhibited the CD4-CD8 + T-cell phenotype. Moreover, TMF expressed cytotoxic markers of TIA1 and Granzyme B. A PCR analysis of T-cell receptor genes revealed peak sizes that were the same in both biopsies, indicating that these two lymphomas were derived from the same clone.

Therapeutic-Dose Warfarin (International Normalized Ratio >1.6) Plus Aspirin Improved Long-Term Patency of Saphenous Vein Graft without Bleeding Complication

Purpose: Saphenous vein graft (SVG) is the most commonly used conduits in coronary artery bypass grafting (CABG), but the disadvantage of SVG is its tendency for progressive failure. We hypothesized that therapeutic-dose warfarin (international normalized ratio [INR] >1.6) plus aspirin improve SVG patency. This study aimed to evaluate the factors contributing to SVG patency.

Methods: Since 2010–2020, 199 patients who underwent isolated CABG using SVG were divided into two groups according to their INR values in the first year: group T (INR >1.6) and group L (INR <1.6).

Results: Group T had 162 SVGs (105 patients) and group L had 151 SVGs (94 patients). The 1-, 4-, and 7-year SVG patency rates were higher in group T than in group L (99%, 96%, and 92% vs. 93%, 86%, and 79%, respectively; p = 0.00378). The 1-, 4-, and 7-year freedom from repeat-revascularization was higher in group T than in group L (100%, 100%, and 99% vs. 98%, 95%, and 87%, respectively; p = 0.0264). Multivariate analysis showed that therapeutic-dose warfarin (p = 0.00204) and target vessel diameter (p <0.0001) were independent risk factors of SVG occlusion.

Conclusion: Therapeutic-dose warfarin (INR >1.6) plus aspirin after CABG improved the long-term patency of SVG and decreased repeat-revascularization rate.

Electron-phonon superconductivity in C-doped topological nodal-line semimetal Zr5Pt3: a muon spin rotation and relaxation (μSR) study

In the present work, we demonstrate that C-doped Zr₅Pt₃is an electron-phonon superconductor (with critical temperatureT_C= 3.8 K) with a nonsymmorphic topological Dirac nodal-line semimetal state, which we report here for the first time. The superconducting properties of Zr₅Pt₃C_0.5have been investigated by means of magnetization, resistivity, specific heat, and muon spin rotation and relaxation (μSR) measurements. We find that at low temperatures, the depolarization rate is almost constant and it can be well described by a single-bands-wave model with a superconducting gap of 2Δ(0)/k_BT_C= 3.84, somewhat higher than the value of BCS theory. From the transverse field μSR analysis, we estimate the London penetration depthλ_L= 469 nm, superconducting carrier densityn_s= 1.83 × 10²⁶ m^-3, and effective massm* = 1.428m_e. The zero field μSR confirms the absence of any spontaneous magnetic field in the superconducting ground state. In order to gain additional insights into the electronic ground state of C-doped Zr₅Pt₃, we also performed first-principles calculations within the framework of density functional theory (DFT). The observed homogenous electronic character of the Fermi surface as well as the mutual decrease ofT_Cand density of states at the Fermi level are consistent with the experimental findings of this study. However, the band structure reveals the presence of robust, gapless fourfold-degenerate nodal lines protected by 6₃screw rotations and glide mirror planes. Therefore, Zr₅Pt₃represents a novel, unprecedented condensed matter system to investigate the intricate interplay between superconductivity and topology.

[Treatment of ITP]

Helicobacter eradication therapy is the first-line therapy for patients with Helicobacter positive idiopathic thrombocytopenic purpura (ITP) in Japan. Indications for treatement in patients with Helicobacter negative, or post-Helicobacter eradicated ITP are platelet counts less than 20×10⁶/l or severe bleeding. The first-line treatment for these patients is corticosteroids. Thrombopoietin receptor agonists (TPO-RAs), rituximab, and splenectomy are second-line treatments for patients with corticosteroid refractory ITP. The choice of a second-line treatment should be determined in consideration of the advantages and disadvantages of each treatment. TPO-RAs are effective in over 80% of patients; however, long-term administration is usually needed. Rituximab treatment ends in four weeks, but its durable response rate is relatively low. The durable response rate of splenectomy is relatively high; however, it causes long-term complications. Effective treatments for patients with ITP who are refractory to second-line treatments have not been established. Some novel drugs are under clinical trials, and a treatment strategy for these patients is expected to be established.

Repair Tension During Arthroscopic Rotator Cuff Repair is Correlated With Preoperative Tendon Retraction and Postoperative Rotator Cuff Integrity

PURPOSE

This study aimed to examine the correlation of repair tension during arthroscopic rotator cuff repair (ARCR) with preoperative factors and to evaluate whether measuring tension during ARCR is effective for predicting rotator cuff integrity after ARCR.

METHODS

Patients who underwent ARCR from May 2014 to June 2017 were enrolled in this study. Inclusion criteria were patients with medium or larger-sized tears and with a minimum of 6 months' follow-up. Patients with a partial repair were excluded. Intraoperative repair tension was measured according to Davidson's method. Correlation of repair tension with preoperative factors was evaluated with Pearson and Spearman correlation coefficient tests. Logistic regression analysis was performed on intraoperative factors, including repair tension, to identify independent predictors of retear after ARCR. Receiver operating characteristic (ROC) curve was used to determine the cutoff value of repair tension for retear.

RESULTS

One-hundred twenty patients met the inclusion criteria. Mean repair tension was 26.6 ± 12.6 N, and retear was found in 29 shoulders (24.2%). Among the preoperative factors, tear size in the mediolateral (P < .001) and anteroposterior (P < .001) directions, DeOrio and Cofield's classification (P <0.001), geometric classification (P <.001), and fatty infiltration of supraspinatus (P = .006) and infraspinatus (P = .003) were significantly correlated with repair tension. However, multivariable logistic regression analysis identified only tear size in the mediolateral direction as an independent predictor of repair tension (P = .036). Logistic regression analysis showed that repair tension (P = .02) and geometric classification (P < .001) are significant factors affecting rotator cuff integrity after ARCR. ROC curve analysis showed the cutoff value of repair tension of large to massive tears for retear to be 35.6 N.

CONCLUSION

This study demonstrated that intraoperative repair tension is strongly correlated with tear size in the mediolateral direction based on preoperative magnetic resonance imaging and that measuring tension during ARCR is effective for predicting rotator cuff integrity after ARCR.

LEVEL OF EVIDENCE

Level IV, prognostic study.

COVID-19-Related Thrombosis in Japan: Final Report of a Questionnaire-Based Survey in 2020

A questionnaire on COVID-19-related thrombosis in patients hospitalized before Aug 31, 2020, was sent to 399 hospitals throughout Japan. Responses were received from 111 (27.8%) with information on 6,202 COVID-19 patients. Of these, 333 and 56 required ventilation or extracorporeal membrane oxygenation (ECMO), respectively, and 212 died (3.4%). D-dimer levels were measured in 75.0% of the patients, revealing that 9.2% and 7.6% exhibited D-dimer increases of 3-8-fold and ≥8-fold the reference value, respectively. Thrombotic events occurred in 108 patients (1.86% of the 5,807 patients with available data) including symptomatic cerebral infarction in 24, myocardial infarction in 7, deep vein thrombosis in 41, pulmonary thromboembolism in 30, and other thrombotic events in 22. Some patients developed multiple thrombotic events. Thrombosis occurred in 32 patients with mild or moderate COVID-19 severity (0.59% of those with data available) and in 52 patients on ventilation or ECMO (13.5% of severe patients for whom data were available). Thrombosis occurred in 67 patients during worsening clinical condition and in 26 during recovery. Anticoagulant therapy was provided to 893 patients (14.6% of the 6,119 patients with available data), the main reasons being provided as elevated D-dimer levels and worsening clinical condition.

Left atrial schwannoma in schwannomatosis: a case report

BACKGROUND

Primary cardiac schwannoma in the left atrium and schwannomatosis are rare diseases.

CASE PRESENTATION

We report the case of a 46-year-old asymptomatic man who had tumor resection for parapharyngeal schwannoma at another institute 1 year ago. He was presented to our hospital for further evaluation of an abnormal cardiac shadow that was found incidentally. Computed tomography and transesophageal echocardiography revealed a cardiac tumor originating from the posterior wall of the left atrium, an atrial septal defect, and two other mediastinal tumors. The cardiac mass was completely excised with normal margins of the surrounding atrial wall. The post-resection defect and atrial septal defect were repaired using bovine pericardium. Pathological findings were compatible with benign schwannoma, and a diagnosis of schwannomatosis was made based on his medical history.

CONCLUSION

Primary cardiac schwannoma is an exceedingly rare tumor, and the incidence in schwannomatosis has not been reported in the literature.

Limiting the Pitch Count in Youth Baseball Pitchers Decreases Elbow Pain

Background

Reducing the number of pitches thrown is regarded as the most effective way to prevent throwing injuries in youth baseball pitchers. However, few studies have compared the effectiveness of limiting the pitch count versus the limiting the number of innings pitched in terms of elbow injuries.

Hypothesis

We hypothesized that, compared with inning limits, pitch count limits would lead to greater decreases in elbow pain, range of motion deficits, positive moving valgus stress test results, and the risk of capitellar osteochondritis dissecans (OCD).

Study Design

Cohort study; Level of evidence, 3.

Methods

This study retrospectively reviewed baseball pitchers aged 8 to 12 years in 2017 and 2018. Inning and pitch count limits in games were set to a daily maximum of 7 innings in 2017 and 70 pitches in 2018. Elbow pain, range of motion, and moving valgus stress test results were evaluated. The presence of capitellar OCD was assessed on ultrasonographic and radiographic images.

Results

A total of 352 pitchers in 2017 and 367 pitchers in 2018 participated. The mean pitch count per game was lower in the pitch count limit (CL) group (52.5 ± 16.0) than in the inning limit (IL) group (98.2 ± 19.5) (P < .001). Compared with the IL group, the CL group had significantly lower rates of elbow pain (40.9% vs 31.9%, respectively; P = .01) and reduced flexion (19.0% vs 10.6%, respectively; P = .001). Multivariate analysis revealed a significant association between elbow pain and age in both the IL and the CL groups (P < .0001 and P = .02, respectively) and between OCD and elbow pain in the CL group (P = .04).

Conclusion

A pitch count limit of ≤70 pitches per day for baseball pitchers ≤12 years could be more protective against elbow pain and reduced flexion than a limit of ≤7 innings per day, but it may not be effective for reducing the risk of capitellar OCD.