Does Youth Baseball Result in Morphologic Changes of the Lateral Elbow? A Prospective MRI Study.

BACKGROUND: Stress from overhead throwing results in morphologic changes to the shoulder in youth baseball players. With greater valgus torque stresses, the elbow experiences injuries specifically attributed to throwing. However, no previous work that we know of has assessed throwing-related morphologic changes of the elbow without associated conditions. QUESTIONS/PURPOSES: (1) Do children who play competitive baseball have enlargement or overgrowth of their radial head shape and/or capitellum compared with the nondominant elbow on MRI? (2) Do children who stop playing year-round baseball have less enlargement of the lateral elbow structures than children who maintain a high level of play? METHODS: A prospective study was conducted between 2015 and 2018 on preadolescent boys who underwent voluntary MRI of their bilateral elbows before the start of the spring baseball season. Twenty-six children agreed to participate out of a four-team league that was asked to participate; their first MRI was obtained at a mean (range) age of 12 years (10 to 13). We also obtained their history related to throwing and performed a physical examination. Players had a mean of 5.6 years of playing before their first MRI, and half the children (13 of 26) were year-round baseball players. Sixty-two percent (16 of 26) reported being either or both a pitcher or catcher as their primary position. No child was excluded from participation. Three years later, these boys were asked to return for repeat MRI and physical examinations. Fifty-eight percent (15 of 26) of players were still playing at the 3-year MRI. Continued play or new onset of pain was documented. Radiographic measurements were then compared between dominant and nondominant arms, and the differences of these changes were compared between those who had continued playing during the study period and those who had quit. The measurements were made in all three planes of the radial head and capitellum, both osseous and cartilaginous. Measurement intrarater and interrater reliability were in the good-to-excellent range (intraclass correlation coefficient 0.77 to 0.98). RESULTS: When we compared dominant and nondominant arms, we found there was no dominant arm overgrowth (difference between baseline and 3-year measurements) in any measurement; for example, sagittal capitellum measurements in dominant arms were 2.5 ± 1.1 mm versus non-dominant arms: 2.8 ± 1.1 mm (mean difference -0.23 [95% CI -0.55 to 0.08]; p = 0.13). There was only undergrowth of the cartilaginous axial diameter of the radial head (change in dominant: 2.5 ± 1.3 mm; change in nondominant: 3.2 ± 1.7 mm; mean difference -0.64 mm [95% CI -1.2 to -0.06]; p = 0.03). There was no enlargement of the lateral elbow structures when children who continued to play were compared with children who stopped playing; for example, the difference in the bone-only growth ratio of the sagittal radial head to humerus of those still playing was 0.001 ± 0.03 and it was 0.01 ± 0.03 for those not playing (mean difference -0.01 [95% CI -0.04 to 0.01]; p = 0.29). CONCLUSION: In healthy children who play baseball for multiple years between the ages of 6 to 11 years, continued torque at the elbow from throwing does not result in morphologic changes as it does in the shoulder. Despite evidence that injuries and surgery because of long-term participation in a throwing sport results in a larger radial head and capitellum, our study presents evidence that outside an injured elbow, throwing alone does not appear to change the morphology of the lateral elbow. Therefore, changes to the radial head size could presuppose other elbow pathology and future study could be performed to better evaluate the correlation. LEVEL OF EVIDENCE: Level I, prognostic study.

Gender differences in the order of appearance of elbow ossification centres.

BACKGROUND: The predictable order of appearance of elbow secondary ossification centres in children is important in interpreting elbow radiographs, most commonly in the context of trauma. The usual sequence of appearance of these ossification centres is given by the acronym CRITOL, but exceptions have been described and are recognised as normal variants. AIM: To investigate the extent to which the appearance of the elbow secondary ossification centres follows a predictable sequence, and to establish the incidence of exceptions to the usual CRITOL order. METHODS: Two-stage retrospective review of 421 elbow radiographs in children at our centre. RESULTS: Of 64 children with two visible ossification centres, there was a 23% overall variant incidence (49 CR, 15 CI). Twenty-eight children had four visible ossification centres, with an overall variant incidence of 32% (19 CRIT, 9 CRIO). The variants were significantly more common in girls than in boys ( p < 0.001). CONCLUSION: Whilst the majority of radiographs remained consistent with the described CRITOL sequence, variance in this order was seen in a quarter of children with two visible ossification centres, and a third of children with four visible ossification centres. Incidence of variance was much more common in girls, reaching statistical significance. Awareness of these normal variations, particularly in girls, should help to avoid misinterpretation.

The dependence of age on ulnar nerve conductive study parameter adaptation after compressive ulnar neuropathy operations in the elbow.

BACKGROUND: According to some studies, peripheral nerve injury healing is prolonged in elderly patients. Compressive ulnar neuropathy in the elbow (UNE) is the second most common compressive mononeuropathy. To our knowledge, no study has investigated the effect of age on the postoperative ulnar nerve injury repair rate. Our aim was to evaluate age-related differences in the electrophysiological parameters before and approximately 100 days after operations for cubital tunnel syndrome. METHODS: This retrospective study included 103 patients who underwent in situ ulnar nerve decompressions in the elbow. The included patients suffered from paraesthesia and hypoesthesia in their ulnar nerve distribution, hypertrophy, and weakening of the hand muscles, which were innervated by the ulnar nerve. Concurrently, these patients met the EGM diagnostic criteria for UNE. The age dependency on the differences between the preoperative and postoperative parameter values that were measured during the conductive studies was estimated using a regression analysis. RESULTS: A statistically significant deceleration of the monitored parameter adaptation, which included segmental conduction velocity in the elbow area and CMAP amplitude during the above-elbow stimulation of the ulnar nerve, was found. CONCLUSIONS: Ulnar nerve injury repair in the cubital tunnel area after a UNE operation proceeds significantly slower in elderly patients.

Comparação entre a avaliação da amplitude articular estática do cotovelo por meio de três diferentes métodos: goniometria, biofotogrametria e goniometria da imagem radiológica / Comparison of evaluation of static elbow range of motion using three different methods: goniometry, biophotogrammetry and radiological goniometry

Introdução: O objetivo deste estudo foi verificar a confiabilidade e objetividade da goniometria e da biofotogrametria para a avaliação de uma posição do cotovelo através da comparação dos dados obtidos por estes métodos com os obtidos pela goniometria radiológica. Material e Métodos: A pesquisa contou com dezesseis indivíduos, sendo seis examinadores e dez avaliados. Para todas as técnicas de medida utilizadas, cada avaliador colheu três medidas de um mesmo ângulo do cotovelo (143º), que foi considerado como ângulo alvo das análises estatísticas e neste estudo chamado de ângulo chave. Resultados: Após a análise estatística, verificou-se baixa e moderada confiabilidade para a goniometria, e alta e muito alta confiabilidade para a biofotogrametria. Quanto à objetividade, verificou-se valores alto e moderado com o uso do goniômetro, ao passo que com a biofotogrametria somente se observaram valores altos. No entanto, as medidas encontradas com essas técnicas não apresentaram boa correlação com os valores obtidos pela goniometria radiológica. Conclusão: A técnica biofotogramétrica apresentou maior confiabilidade e objetividade em comparação com a goniometria sem, no entanto, apresentar correlação de seus dados com os obtidos pela goniometria radiológica.

Introduction: The aim of this study was to verify the reliability and objectivity of goniometry and biophotogrammetry to evaluate one specific elbow position. Data obtained from these two methods were compared with radiological goniometry data. Material & Methods: The group was composed by sixteen subjects: six examiners and ten volunteers. For all measurements used in this research each examiner took three measures of same angle of the elbow (143º) which was considered as target angle of statistical analyses in this study called key angle. Results: After statistical analysis, it was checked low and moderated reliability to the goniometry and high and very high reliability to biophotogrammetry. In regards to objectivity, it was observed higher and moderate reliability with the goniometer while with the biophotogrammetry only higher values. Though, measurements found with these techniques did not show good correlation with radiological goniometry values. Conclusion: The biophotogrammetry technique showed more reliability and objectivity in comparison to goniometry, however did not show correlation with radiological goniometry data values.

[Order of appearance of ossification centers in the elbow of Mexican children between 6 months and 12 years old]. / Aparición de los centros de osificación en el codo en niños mexicanos entre los 6 meses y los 12 años de edad.

INTRODUCTION: Existing data of the order of appearance of ossification centers is from Anglo-Saxon literature. This literature describes the following order of appearance of the ossification centers of the distal humerus as follows: lateral condyle appears before one year of age, but it might delay up to 18-24 months; medial epicondyle between 5 to 6 years of age; the medal condyle between 9 to 10 years of age; the lateral epicondyle is the last one to ossify, between 10 to 12 years of age. Proximal radius ossifies between 3.8 and 4.5 years; olecranon at 6 to 8 years of age. METHODS: We studied 240 elbows and classified them in 6 groups according to the age of appearance of ossification centers. Anteroposterior and lateral radiographs were taken, and analyzed. RESULTS: We found a delay in the manifestation of the olecranon and the medial epicondyle. In base of our clinical observations, the ossification centers present later in Mexican children.

Biomechanics and development of the elbow in the young throwing athlete.

This article reviews basic concepts in fundamental elbow biomechanics, particularly how they relate to the skeletally immature elbow in throwing athletes. Adult phases of throwing and the forces generated in each phase are compared with the developmental phases of throwing in children. The impact of elevated forces, poor mechanics, and poor coordination are emphasized as they relate to potential areas of injury in the skeletally immature. Finally, concepts in prevention focused on biomechanics are offered.

Which morphologies of synovial folds result from degeneration and/or aging of the radiohumeral joint: an anatomic study with cadavers and embryos.

The synovial folds of the radiohumeral joints in cadaveric elbows from 179 elderly subjects and 40 embryos were investigated macroscopically and histologically to determine any morphologic changes caused by aging or degeneration. The anterior and posterior folds found in the elderly population shared characteristics of folds seen in embryos, with some modifications, and were thought to originate from the primitive septum. Proportionally, the length, width, and thickness of these folds were consistent between adults and embryos. However, the embryonic folds showed a homogenous morphology. In contrast, in the adult the anterior fold was characterized by a shorter and narrower villous pattern, and the posterior fold tended to be wider. Lateral extension of the anterior or posterior folds was also observed. Moreover, the lateral fold, never seen in embryos, was present and characterized by a hard plicate pattern in the adult. These derived or specific morphologies in adults probably result from alterations in the movement of the radial head caused by aging.

Force development of dynamic and static contractions in children and adults.

There are still unclarified points remaining in regard to the characteristics of force development in children who are immature in their basic activities in daily living. Moreover, there are morphological, histological, and biochemical differences between immature and mature muscles. In the present study, dynamic elbow flexion and static contractions which were performed by elbow flexors with maximum effort were examined by force-velocity and force-time relationships and electromyograms (EMG) in six-year-old children and in adults. In dynamic contractions with various loads, the force-velocity relationship for children was (P + 5.65) (v + 1.48) = 19.51, and (P + 14.65) (v + 2.26) = 96.21 for adults. The maximum power in children and adults was 22.8 watts and 160.8 watts, respectively. The contraction delay in children was greater than that in adults for every relative load. In static contractions, the maximum rate of force development for children was significantly lower than that for adults at each pre-tension. With an increase in pre-tension, the adult rate showed a tendency to decrease, whereas the rate for children showed no change. The electromechanical delay observed in children was significantly greater than that in adults. For dynamic and static contractions, the contractile speed in children was lower than that in adults.

Arthrography in the posttraumatic elbow in children.

Radiographic interpretation of children's elbows after trauma can be perplexing because of the large proportion of unossified cartilage relative to bone. The numbers of ossification centers appearing at different ages also complicate the interpretation. This study summarizes arthrographic experience in 10 children who sustained elbow trauma. Nine children had arthrography performed 5-24 months after injury. Seven patients had supracondylar or condylar fractures, one patient had a proximal radial fracture, and two patients had suspected osteochondritis dissecans. Arthrography was useful in delineating the integrity of the joint surfaces and in identifying healed rotated fracture components, cartilaginous spurs, nonunion of unossified fragments, and the normal physis. A small scarred joint and intraarticular loose bodies also were demonstrated. Elbow arthrography, though clearly not indicated for all pediatric elbow trauma, can contribute valuable information in the complex elbow fracture.