Overuse Injuries of the Upper Extremity in the Competitive Athlete: Magnetic Resonance Imaging Findings Associated with Repetitive Trauma

Infrastructure and Injury Prevention in Cycling

The focus of this article centers on bicycle injury prevention and related infrastructure. The article discusses the current epidemiology of cycling injuries, and known prevention strategies, specifically individual recommended practices related to helmet use in both adult and pediatric populations. The article also discusses different ways in which the environment plays a role in protecting cyclists from injuries, and what environmental changes have been adopted to reduce the likelihood for cycling injuries.

Autonomic modulations of heart rate variability are associated with sports injury incidence in sprint swimmers

OBJECTIVES

Young athletes' participation in competitive sports is becoming increasingly common, and this increased involvement raises concerns about the occurrence of overtraining and sports injuries. Since these issues are poorly understood, this study analyzed heart rate variability, stress/recovery relationship, and sports injury incidence during a training macrocycle of young sprint and endurance swimmers.

METHODS

Thirty teenage swimmers (aged 12 to 17 years) were divided into two groups as follows: Sprint (n = 17) and Endurance (n = 13). Subjects were evaluated over 20 weeks, based on the following three schedules: general, specific, and competitive. In addition to heart rate variability and sports injury incidence, the Recovery-Stress-Questionnaire of Athletes was used to analyse stress/recovery states in athletes. All procedures were developed at the initial moment and at the end of each periodization step.

RESULTS

The Sprint group presented a reduced standard deviation of normal-normal beats (73.0 ± 6.6 vs. 54.1 ± 3.5 ms; p < 0.05) and root mean square of the successive differences (55.3 ± 6.2 vs. 42.0 ± 3.7 ms; p < 0.01) from the period of general preparation until the time of competition. Recovery-stress monitoring was affected only by the swimming training periodization (p < 0.05). During the general period, differences between recovery and stress scales were correlated directly with the root mean square of the successive differences (r = 0.576; p = 0.001), the standard deviation of instantaneous variability beat-to-beat (r = 0.521; p = 0.003) and the triangular index (r = 0.476; p = 0.008). Differences between general recovery and stress scales were inversely correlated with geometric indexes after the specific training period. Moreover, the Sprint group showed a higher incidence of sports injury than the Endurance group (0.0214 ± 0.0068 vs. 0.0136 ± 0.0050 cases/1000 hours).

CONCLUSION

Sprint training was associated with progressive activation of the sympathetic nervous system as well as a higher incidence of sports injury in comparison to endurance swimming during a training macrocycle.

Elbow MRI Findings Do Not Correlate With Future Placement on the Disabled List in Asymptomatic Professional Baseball Pitchers

BACKGROUND

Injury rates among professional baseball players may reach as high as 5.8 per 1000 encounters, with pitchers being most vulnerable on account of the excessive biomechanical load on the upper extremity during the throwing motion. Anatomically, the shoulder is the most common site of pitching-related injury, accounting for 30.7% of injuries, closely followed by the elbow at 26.3%. Characteristic valgus loading imparts a predictable constellation of stresses on the joint, including medial tension, lateral compression, and posterior medial shearing. The degenerative cohort of tissue changes that result are readily detected on magnetic resonance imaging (MRI). It is not yet known whether such findings predict future placement on the disabled list (DL) in asymptomatic Major League pitchers.

HYPOTHESIS

Abnormal soft tissue and osseous changes detected on MRI of the throwing elbow in asymptomatic professional pitchers will impart an increased risk of subsequent transfer to the DL in the season after MRI.

STUDY DESIGN

Retrospective cohort study.

LEVEL OF EVIDENCE

Level 3.

METHODS

The study aimed to examine a potential association between the total number of innings pitched (approximate lifetime valgus load) and the typical MRI degenerative changes, hypothesizing a rejection of the null hypothesis. A total of 26 asymptomatic professional pitchers from a single Major League Baseball (MLB) organization and its various minor league affiliates underwent MRI of their dominant elbow from 2003 to 2013 as a condition of their contract signing or trade. Twenty-one of those pitchers played at the Major League level while 5 played with the team's minor league affiliates including both the AA and AAA levels. Asymptomatic was defined as no related stints on the DL due to elbow injury in the 2 seasons prior to MRI. A fellowship-trained musculoskeletal radiologist reevaluated the studies after being blinded to patient name, injury history, and baseball history. A second investigator collected demographic data; this included total career number of innings pitched and any subsequent DL reports for each subject while remaining blinded to the MRI results.

RESULTS

The mean age at the time of MRI was 29.6 years (range, 19-39 years). The mean number of innings pitched was 1111.7. Of the 26 pitchers, 13 had scar remodeling of the anterior bundle of the ulnar collateral ligament (UCL). Of those, 4 had partial-thickness tears of the anterior bundle of the UCL, ranging from 10% to 90% of the total thickness. Twelve had articular cartilage loss within the posteromedial margin of the ulnohumeral joint, and 12 had posteromedial olecranon marginal osteophytes. Seven pitchers had degeneration of the common extensor tendon origin, 10 had degeneration of the flexor pronator mass, 9 had insertional triceps tendinosis, 2 had enthesopathic spurs at the sublime tubercle, 3 had osteochondral intra-articular bodies, and 2 subjects had joint effusions. In the year after MRI, 6 pitchers were placed on the DL for elbow-related injuries. There was no robust correlation between any single MRI finding and subsequent transfer to the DL, and no statistically significant correlation between number of innings pitched and MRI findings, although some trends were observed for both.

CONCLUSION

MRI findings in asymptomatic MLB pitchers were not associated with placement on the DL within the subsequent year. While a trend was observed with olecranon osteophytes and subsequent DL placement ( P = 0.07), this finding did not reach statistical significance. Furthermore, there was no robust correlation between the number of innings pitched with the presence of any of the aforementioned degenerative changes on MRI.

CLINICAL RELEVANCE

The characteristic structural transformation that occurs in the throwing elbow of professional pitchers is predictable and readily detectable on MRI. However, this study suggests that these changes are not predictive of near-term placement on the DL in those who are asymptomatic. Abnormal findings on MRI, even high-grade partial UCL tears, do not correlate with near-term placement on the DL, mitigating their potential negative impact on signing decisions.

Asymptomatic Elite Adolescent Tennis Players' Signs of Tendinosis in Their Dominant Shoulder Compared With Their Nondominant Shoulder

CONTEXT

Tennis is an asymmetric overhead sport with specific muscle-activation patterns, especially eccentrically in the rotator cuff. Magnetic resonance imaging (MRI) findings in asymptomatic adolescent elite tennis players have not previously been reported.

OBJECTIVE

The first aim of the study was to describe MRI findings regarding adaptations or abnormalities, as well as muscle cross-sectional area (CSA), of the rotator cuff. The second aim of the study was to investigate the rotator cuff based on the interpretation of the MRI scans as normal versus abnormal, with the subdivision based on the grade of tendinosis, and its association with eccentric rotator cuff strength in the dominant arm (DA) of the asymptomatic elite adolescent tennis player.

SETTING

Testing environment at the radiology department of Medicinsk Röntgen AB.

PATIENTS OR OTHER PARTICIPANTS

Thirty-five asymptomatic elite tennis players (age = 17.4 ± 2.7 years) were selected based on ranking and exposure time.

INTERVENTION(S)

We assessed MRI scans and measured the CSA of the rotator cuff muscle. The non-DA (NDA) was used as a control. In addition, eccentric testing of the external rotators of the DA was performed with a handheld dynamometer.

RESULTS

The DA and NDA displayed different frequencies of infraspinatus tendinosis (grade 1 changes) (P < .05). Rotator cuff measurements revealed larger infraspinatus and teres minor CSA (P < .05) in the DA than in the NDA. Mean eccentric external-rotation strength in the DA stratified by normal tendon and tendinosis was not different between groups (P = .723).

CONCLUSIONS

Asymptomatic adolescent elite tennis players demonstrated infraspinatus tendinosis more frequently in the DA than in the NDA. Clinicians must recognize these tendon changes in order to modify conditioning and performance programs appropriately.

High-grade pronator teres tear in a cricket batsman

We present a case of a torn pronator teres muscle of the right forearm that occurred following prolonged batting during recreational cricket. Previous reports of cricket injuries to batsmen describe phalanx fractures due to direct ball impact. However, we could find no prior reports of pronator teres or other upper-extremity muscle injury. Our patient demonstrated a high-grade tear to the pronator teres muscle and no injury to the collateral ligaments. In this case, repetitive use of the pronator and flexor muscles with quick acceleratory movements stressed this muscle group and resulted in injury.

Stress fractures of the ribs and upper extremities: causation, evaluation, and management

Stress fractures are common troublesome injuries in athletes and non-athletes. Historically, stress fractures have been thought to predominate in the lower extremities secondary to the repetitive stresses of impact loading. Stress injuries of the ribs and upper extremities are much less common and often unrecognized. Consequently, these injuries are often omitted from the differential diagnosis of rib or upper extremity pain. Given the infrequency of this diagnosis, few case reports or case series have reported on their precipitating activities and common locations. Appropriate evaluation for these injuries requires a thorough history and physical examination. Radiographs may be negative early, requiring bone scintigraphy or MRI to confirm the diagnosis. Nonoperative and operative treatment recommendations are made based on location, injury classification, and causative activity. An understanding of the most common locations of upper extremity stress fractures and their associated causative activities is essential for prompt diagnosis and optimal treatment.

Magnetic resonance imaging of primary and concomitant flexor enthesopathy in the canine elbow

Flexor enthesopathy is a recently recognized elbow disorder in dogs and considered to be an important differential diagnosis for elbow lameness. Primary and concomitant forms of the disease have been previously described and treatments differ for the two forms. The goal of this prospective study was to compare magnetic resonance imaging (MRI) findings for dogs with primary flexor enthesopathy (n = 17), concomitant flexor enthesopathy (n = 23), elbow dysplasia alone (n = 13), and normal elbows (n = 7). Each elbow joint underwent MRI using the same low-field scanner. Sequences included transverse and sagittal T1-weighted (before and after IV contrast), transverse and sagittal T2-weighted, and dorsal STIR. For each elbow, MRI lesions were recorded based on a consensus of two observers unaware of group status. Magnetic resonance imaging lesions involving flexor tendons were found in 100% of clinically affected joints with primary flexor enthesopathy and 96% of clinically affected joints with concomitant flexor enthesopathy. Thickened flexor muscles were the most common lesions, followed by hyperintense tendon signal and contrast enhancement. Irregular, thickened medial humeral epicondyle, edema, and calcified body lesions were less frequently observed. Magnetic resonance imaging characteristics of flexor enthesopathy were not found in normal joints or those affected by elbow dysplasia alone. No significant differences in frequencies and details of individual MRI characteristics were found between primary and concomitant flexor enthesopathy groups. Findings indicated that MRI is a sensitive technique for detection of flexor enthesopathy lesions in dogs, however, MRI characteristics do not allow differentiation of primary versus concomitant forms of the disease.

Upper-extremity stress fractures: distribution and causative activities in 70 patients

Stress fractures of the upper extremity and thorax are often unrecognized injuries in athletes and nonathletes. The authors reviewed the causative activities and anatomic distribution of rib and upper-extremity stress fractures. Radiographic and clinical information was reviewed for each case to determine anatomic site and causative activity of each stress fracture. Stress fracture, although an uncommon diagnosis outside the lower extremity and lumbar spine, should be included in the differential diagnosis of patients with pain in the ribs and upper extremity.

Could forearm Kinesio Taping improve strength, force sense, and pain in baseball pitchers with medial epicondylitis?

OBJECTIVE

To determine short-term effects of applied forearm Kinesio Taping (KT) on pain, wrist flexor strength, and force sense for baseball players with medial epicondylitis (ME).

DESIGN

Case-control repeated measures study.

SETTING

Clinical sports medicine research laboratory in a medical university.

PARTICIPANTS

A group of 10 baseball players with ME (ME group) and another group of 17 healthy collegiate athletes (healthy group).

INTERVENTION

Three taping conditions were applied in both groups: (1) no taping applied, (2) placebo taping applied (PT), and (3) KT applied.

MAIN OUTCOME MEASURES

Three variables were measured including maximal wrist flexor strength, related/absolute force sense errors, and pain scale (pressure pain and pain tolerance) under 3 taping conditions.

RESULTS

No significant relationship was found either in maximal wrist flexor strength or in related force sense errors between the 2 groups with taping applied, except absolute force sense errors (P = 0.037). Both the healthy group and the ME group in absolute force sense measurement significantly decreased the errors in PT and KT conditions. Also, the tolerance of pressure pain also improved in both the healthy group and the ME group when performing PT and KT conditions.

CONCLUSIONS

Forearm KT may enhance absolute force sense and improve pain condition for both healthy athletes and athletes suffering from ME when placebo and KT applied. However, KT did not result in significant changes in maximal wrist flexor strength for either group.

Enthesopathies as occupational stress markers: evidence from the upper limb

Enthesopathies--that is, "musculo-skeletal stress markers"--are frequently used to reconstruct past lifestyles and activity patterns. Relatively little attention has been paid in physical anthropology to methodological gaps implicit in this approach: almost all methods previously employed neglect current medical insights into enthesopathies and the distinction between healthy and pathological aspects has been arbitrary. This study presents a new visual method of studying fibrocartilaginous enthesopathies of the upper limb (modified from Villotte: Bull Mém Soc Anthropol Paris n.s. 18 (2006) 65-85), and application of this method to 367 males who died between the 18th and 20th centuries, from four European identified skeletal collections: the Christ Church Spitalfields Collection, the identified skeletal collection of the anthropological museum of the University of Coimbra, and the Sassari and Bologna collections of the museum of Anthropology, University of Bologna. The analysis, using generalized estimating equations to model repeated binary outcome variables, has established a strong link between enthesopathies and physical activity: men with occupations involving heavy manual tasks have significantly (P-value < 0.001) more lesions of the upper limbs than nonmanual and light manual workers. Probability of the presence of an enthesopathy also increases with age and is higher for the right side compared with the left. Our study failed to distinguish significant differences between the collections when adjusted for the other effects. It appears that enthesopathies can be used to reconstruct past lifestyles of populations if physical anthropologists: 1) pay attention to the choice of entheses in their studies and 2) use appropriate methods.

Lesões desportivas na natação

O estudo objetivou analisar a ocorrência de lesões em nadadores, associando-as a fatores de risco específicos da modalidade e do atleta. Fizeram parte desse estudo 215 atletas, de ambos os sexos, participantes dos principais campeonatos promovidos pela Federação Aquática Paulista. Os dados foram obtidos por meio de Inquérito de Morbidade Referida, constituído por perguntas relacionadas ao atleta, modalidade e referentes ao tipo, mecanismo e local da lesão. A análise entre variáveis antropométricas e presença de lesão foi realizada pelo teste t de Student ou pelo teste não paramétrico de Mann Whitney. Para relação entre as especificidades e o tipo, mecanismo e local da lesão, utilizou-se o teste de Goodman. Resultados significantes foram obtidos entre os atletas lesionados com mais idade e anos de treinamento. Segundo o mecanismo da lesão, o volume dos treinos é a principal causa de ocorrências de lesões e as tendinopatias são as lesões mais comuns. O ombro é o local mais acometido pelas diferentes especialidades, com exceção dos nadadores de peito que referiram a virilha. Conclui-se a partir dos achados que a exposição dos nadadores a prática esportiva associada ao volume de treinamento estão relacionadas com as frequentes lesões nestes atletas.

Measurement of a number of indices of hand and movement angles in pianists with overuse disorders

Abduction angles of the thumb and little finger, hand span, length of thumb, middle finger and little finger were measured using radiographs of the right hand with the thumb and the little finger abducted, in a comparative study of 220 pianists with overuse disorder and 62 unaffected pianists. Overuse disorders included tenosynovitis, lateral and medial epicondylitis, forearm flexor muscle pain, distal tendinitis of the wrist extensors and flexors and intrinsic muscle pain. Hand span or other hand size parameters showed significant differences, while abduction angles showed no difference. The patients' group had smaller hand size than the controls when analyzed for tenosynovitis, epicondylitis and muscle pain. From these results we hypothesize that pianists with small hands tend to hyper-abduct and hyper-extend the thumb to attain greater hand span. Their little finger is also stiffer and the hypothenar muscle and the wrist flexors need greater strength to resist the reaction force in each piano key.

Subsistence activities and the sexual division of labor in the European Upper Paleolithic and Mesolithic: evidence from upper limb enthesopathies

Studies of cultural artifacts and faunal remains from European Upper Paleolithic and Mesolithic sites indicate a shift in hunter gatherer subsistence strategies, involving an intensification and diversification of resource exploitation relative to earlier foragers during the Tardiglacial and Postglacial periods. This trend has been recognized as well through the analysis of non-pathological skeletal adaptations of the upper limbs of European Upper Paleolithic human fossils. These paleoanthropological studies of adaptive bone modeling also raise the question of female use of throwing-based weapon technology in the Upper Paleolithic. Here, we studied another type of osteological marker of activity, enthesopathies, of the upper limb remains of 37 European Upper Paleolithic and Mesolithic human fossils, with the goal of testing two hypotheses: 1) that activity levels were heightened at the end of Upper Paleolithic and into the Mesolithic relative to earlier foragers of the Gravettian, and 2) that there was an absence of a marked sexual division of labor in European hunter-gatherers during this time span. Our results are consistent with the first hypothesis; upper limb enthesopathies are significantly less frequent in the Gravettian group, but raise doubts about the second hypothesis. Four males exhibit lesions that can be confidently associated with throwing activities, while no females exhibit such lesions.

Effect of equitation training on health and physical fitness of college females

Limited information exists concerning equitation as a viable form of physical activity. The study's purpose was to quantify effects of an equitation training program on health and physical fitness of college females. Following written informed consent, 15 college females enrolled in equitation and 10 controls (age = 23.6 +/- 2.5 years; ht = 165.3 +/- 5.3 cm; wt = 62.4 +/- 3.4 kg) underwent a comprehensive pre- and post-series of tests to assess cardiorespiratory response (Bruce; VO2(peak), HR(peak), VE(peak), RER(peak), MAP(peak), RPP(peak)), body composition (body mass, body fat, fat-free mass), muscular power [Wingate; peak and mean power (MP), total power output, fatigue index (FI)], muscular strength (curl-ups, reverse sit-ups, pushups, handgrip), blood chemistry, and coronary risk. The equitation group trained at various equine gaits for 14 weeks, 5 days/week. Multivariate analyses of variance (Wilks' Lambda) indicated a significant main effect of training across muscular power (F (4,25) = 3.965; P = 0.013), but not across cardiorespiratory response (F (11,18) = 1.472; P = 0.225), body composition (F (3,26) = 1.081; P = 0.375), or muscular strength (F (4,25) = 2.172; P = 0.102). Pre-post improvements in MP (+13.3%; P = 0.01), total work output (+11.8%; P = 0.015), and FI (-10.5%; P = 0.038) were observed. Nonsignificant improvements of 8.5-11.4% were observed in muscular strength and body composition. In conclusion, equitation does not provide an adequate stimulus to improve health and fitness in young adults. Individuals who participate in equitation need to supplement this activity with traditional aerobic and load-bearing training regimens.