Meyers FP Injuries SportsMed'01.pdf

IM IIIDV C'l IMin Sports Med 2001; 31(1): 61-73IIMJUKT V^LIINIV^ 0112-1642/01/000161/S22,00/0

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Fast Pitch Softball InjuriesMichael C. Meyers,^ Barrett R. Brown'^ and Joel A. Bloorn^

1 Human Performance Research Center, Department of Sports and Exercise Sciences,West Texas A&M University, Canyon, Texas, USA

2 Department of Health and Human Performance, University of Houston, Houston, Texas, USA

ContentsAbstract 611, History of Fast Pitch Softball 622, Incidence of Injuries 62

2.1 Head Injuries 642.2 Upper Extremity injuries 642.3 Lower Extremity injuries 642.4 Thoracic and Abdominai Injuries 65

3, Aetiology 653.1 Collisions 653.2 Base Running 653.3 Playing Surfaces 663.4 Age and Experience 663.5 Physical Demands 673.6 Overuse 673.7 Contributory Factors 68

4, Prevention 684.1 Safer Playing Environment 684.2 Coaching and Piayer Education 694.3 Conditioning 69

5, Conciusion 70

Abstract The popularity of fast pitch softhall in the US and throughout the world is welldocumented. Along with this popularity, there has been a concomitant increasein the numher of injuries. Nearly 52% of cases qualify as major disabling injuriesrequiring 3 weeks or more of treatment and 2% require surgery. Interestingly,75% of injuries occur during away games and =31% of traumas occur duringnonpositional and conditioning drills. Injuries range from contusions and ten-dinitis to ligamentous disorders and fractures. Although head and neck traumasaccount for 4 to 12% of cases, upper extremity traumas account for 23 to 47% ofall injuries and up to 19% of cases involve the knee.

Approximately 34 to 42% of injuries occur when the athlete collides withanother individual or object. Other factors involved include the quality of playingsurface, athlete's age and experience level, and the excessive physical demandsassociated with the sport. Nearly 24% of injuries involve base running and aredue to poor judgement, sliding technique, current stationary base design, un-orthodox joint and extremity position during ground impact and catching of

62 Meyers et al.

cleats. The increasing prevalence of overtraining syndrome among athletes hasbeen attributed to an unclear definition of an optimal training zone, poor com-munication between player and coach, and the limited ability of bone and con-nective tissue to quickly respond to match the demands of the sport. This has ledroutinely to arm, shoulder and lumbar instability, chronic nonsteroidal anti-in-flammatory drug (NSAID) use and time loss injuries in 45% of pitching staffduring a single season.

Specific attention to a safer playing environment, coaching and player educa-tion, and sport-specific training and conditioning would reduce the risk, rate andseverity of fast pitch traumas. Padding of walls, backstops, rails and dugout areas,as well as minimising use of indoor facilities, is suggested to decrease the numberof collision injuries. Coaches should be cognisant of overtraining, vary day-to-day training routines to decrease repetitive musculoskeletal stress, focus on motorskills with equal emphasis on speed and efficiency of movement, and use drillsthat reinforce sport-specific, decision making processes to minimise mental mis-takes. Conditioning programs that emphasise a combination of power, accelera-tion, flexibility, technical skill, functional capacity and injury prevention arerecommended. Due to the limited body of knowledge presently available on thissport, a greater focus on injury surveillance would provide a clearer picture ofinjury causation and effective management procedures, leading toward safer par-ticipation and successful player development.

1. History of Fast Pitoh Softball

The popularity of Softball in the US and through-out the world is well documented. ['" 1 Softball hasbecome a staple of organised sport programs inschools, recreational and industrial leagues, militaryinstallations and intemationai competitions.t*'^' AtSoftball's inception as an indoor sport in 1887 atthe Chicago Farragut Boat Club the game was orig-inally referred to as kittenball, pumpkin ball or mushball.I^-' l League play began in 1900, rules werepublished by 1906 and the official name 'softball'was coined by W. A. Hakanson in 1926. In the 1930s,the sport moved outdoors and city, state and na-tional play was organised with the creation of theAmateur Softball Association (ASA), the nationalgoverning body in the US.1 1 During this time, in-formal physical education programs were popular-ised and Softball could be found in 90% of women'scollegiate athletics programs.t' -''*! Today, =1.23 mil-lion athletes in the US compete in over 82 000 fastpitch junior Olympic teams consisting of playersaged =18 years.I'^l Of these, 96% or 1.19 million(79 000 teams) of young competitors are female.

Early interest regarding orthopaedic injury andtreatment in softball was limited, especially in fastpitch.['^'''1 It was initially thought that the under-hand pitching style and limited physical contactamong players associated with the more popularslow pitch game resulted in minimal stress and lim-ited predisposition to injury compared with base-ball.[^'^l With the advent of Title IX legislation andincreased exposure of women's sports in the US,there has been a steady rise in the number of fastpitch athletes participating in programs from highschool to professional leagues.''^1 However, this in-creased participation has led to a dramatic increasein the number of injuries, accelerating renewed in-terest in and a need for additional research in this

2. Incidence of Injuries

As previously mentioned, the majority of softballliterature has focused on slow pitch injuries, '"' ^"^^]with limited attention to the high velocity and splitsecond timing associated with the fast pitch envi-ronment, t'^l Due to the increased popularity of fastpitch softball within the last decade, a greater in-

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Fast Pitch Softball Injuries 63

terest in understanding the forces, biomechanicsand similarities of the sport to baseball has resultedin a resurgence of focus on this growing sport.

According to early information derived from theNational Athletic Injury/Illness Reporting System(NAIRS) involving 10 teams during the 1975 to 1978National Collegiate Athletic Association (NCAA)women's softball season, there were 1.8 significantinjuries per 1000 athlete exposures and 8.7 signif-icant injuries per 100 athletes.^','' A significant in-jury was defined as a minimum loss of 1 week ofplaying time. Based on the mean annual rate ofinjuries, 40% of trauma cases were diagnosed assprains, 25% as various fractures, 12% as muscularstrains, 4% as neuro-related, 4% attributed to chronicorthopaedic origin, 2% as dental fractures and 13%involved various other injuries. The authors alsonoted that 52% of cases qualified as major disablinginjuries requiring treatment and/or rehabilitationfor 3 weeks or more before optimal return to playwas established and 2% required surgical interven-tion.1'^' Nearly 25% of cases revealed further com-plications or recurrent trauma. Interestingly, 75%of all injuries and 37% of significant injuries oc-curred during away games each season.

A more recent report from the NCAA InjurySurveillance System (ISS) sampled 57 member in-stitutions according to reportable injuries, numberof athletic exposures and injury rate.I'l Areportableinjury was defined as any trauma resulting in 1 ormore days of time loss. An athletic exposure wasconsidered to be any activity leading to potentialinjury during a single practice or game. The injuryrate was determined by calculating the number ofinjuries per total athletic exposures x 1000 to de-rive a ratio. Based on a seasonal total of 2249 games,2780 practices and 72 125 total athletic exposures(26 834 at games and 45 291 at practices), 161 in-juries (injury rate 3.6) occurred during practice and143 (injury rate 5.3) occurred during games. Ofthese, 76% of practice cases were diagnosed as newinjuries compared with 91% of those occurring dur-ing games. All remaining game and practice casesinvolved reaggravation of injuries from the sameseason, injury recurrence from the previous sea-

son, additional complications from an injury oc-curring within the same season and recurrence ofother sport and nonsport trauma. Approximately82% of practice trauma resulted in a time loss of 1to 6 days, whereas a similar time loss occurred with69% of game injuries. No fatal or catastrophic non-fatal injuries were reported.

Of special note is where and when the athletictrauma occurred. Of the limited seasonal informa-tion available, 71% of practice injuries occurredduring the preseason, whereas 92% of game inju-ries occurred during the regular NCAA season.!'^More cases were reported following away games(69%) than after home games (31 %), with 36% and50% of game injuries occurring during the first tothird and the fourth through sixth innings of play,respectively. 31 % of NCAA practice traumas oc-curred during nonpositional and conditioning drills,with the remaining injuries attributed to base run-ning (13%), outfield (13%), infield (12%), pitching(10%), batting (9%) and catching (8%) situations.During games, 28% of injuries were attributableto base running, with others occurring in the infield(17%), batting (15%), outfield (14%), pitching (12%)and catching (11%) positions.'''

Overall, the type of injuries experienced by ath-letes is influenced by practice or game situations.Approximately 34% of practice injuries consist ofmusculotendinous strains and incomplete tears, fol-lowed by contusions (19%), incomplete ligamen-tous tears and sprains (14%), and tendinitis andinflammation (13%).I'' Fractures, torn cartilage,hyperextensions and concussions have also beenreported, as have a minimal number of lacerations,acromioclavicular joint separations, neurologicaltraumas and stress fractures. Bleeding occurs inonly 4% of practice cases and only 5% of injuriesresult in surgery.'^l

In sharp contrast, are the types of injuries expe-rienced during games. Approximately 45% of inju-ries involve contusions, 23% complete and incom-plete ligamentous tears and sprains, 15% completeand incomplete musculotendinous tears and strains,and 10% fractures.!^] Other less frequently reportedinjuries include concussion, inflammation, lacera-

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64 Meyers et al.

tion, abrasion, hyperextension and joint subluxa-tion. Interestingly, 12% of game injuries result inbleeding and 9% of cases require in-season or post-season surgery, indicative of higher intensity com-petition when compared to practice cases.1^1

2.1 Head Injuries

Head and neck trauma accounts for 4 to 12%of cases involving NCAA women's fast pitch ath-letes.f''^' At the younger levels of competition, mildtraumatic brain injury (MTBI) comprises 2.1% ofhigh school fast pitch cases, with a 0.46 injury rateper 100 player-seasons.'"" Of these, the majorityof traumas are direct cranial blows, ocular traumasor mouth and dental mishaps.l^'^l Approximately94% of head injuries have been reported as firstdegree cerebral concussions.''1 However, incidencesof ocular injuries may be underestimated, since manycases are documented as minor facial trauma withlimited ophthalmic follow-up by the athlete.t^^l

2.2 Upper Extremity injuries

Upper extremity trauma accounts for 23 to 47%of all female fast pitch injuries.[^' Although 38% ofall upper extremity injuries are specific to the shoul-der, nearly 32% of cases involve the upper arm,elbow or wrist regions and 27% involve varioushand, finger and thumb areas.'" Types of traumarange from oedema, ecchymosis, point tendernessand neurological dysfunction' '' '' ''"' ' to numerousforms of fatigue or stress fractures.''''''*]

Injuries to the shoulder typically include ante-rior and/or posterior arthralgia, inflammation, insta-bility and increasing weakness due to overuse.'^^'^^'Various musculoskeletal strains, primarily involv-ing the trapezius, biceps, pectoralis and rotator cuffcomplex, are conimon.' -' -^^] Excessive reactionforces during throwing or sliding have resulted inrotator cuff tendinopathy, subacromial and glenoidimpingement syndrome, and acromioclavicular jointdisorders.[".39-4ii

Upper arm trauma, in both male and femaleathletes, is attributed to significant throwingforces.t-''*' ''-^! Point tenderness, contusions fromblunt contact, prodromal pain while throwing, and

triceps fibrosis with radial nerve compression andrupture have been reported.I '*"^ ] The majority ofemergency cases involve spiral and oblique frac-tures of the humerus.[30.32-34,36i

Ulnar nerve compressions, with neuritis, arthral-gia and tendinitis with concomitant oedema, are hall-mark injuries attributed to overuse and poor pitch-ing mechanics specific to the elbow region.t^'^1There have also been numerous cases involving ra-dial nerve damage associated with denervation andpalsy distal to the elbow following abrupt cubitalextension and hyperextension.'^^'^'l

The majority of discomfort associated with theforearm involves tendinitis. A combination of armspeed and the extreme forces experienced with aninflexible limb often results in ulnar fatigue frac-tures and associated oedema reported in pitchers.'^^'Hand and wrist traumas include various finger andthumb sprains, primarily attributable to batting mis-haps and from falling on outstretched arms duringsliding.f^J Tendinitis and inflammation, metacarpalstress fractures and diminished neurological sensa-tion are especially prevalent among pitchers.'^^-^'I

2.3 Lower Extremity injuries

Lower extremity trauma accounts for 40 to 58%of total injuries in a single fast pitch season.''-"JUp to 19% of all cases include the knee, followedby ankle (11%), upper (10%) and lower leg (6%)traumas.'"] Approximately 36% and 22% of lowerleg injuries are specific to the knee and ankle re-gions, respectively.'"

Injuries to the upper leg consist of various con-tusions, and quadriceps and hamstring strains.'^'Patellofemoral arthralgia and inflammation, and me-dial collateral ligament (MCL) tears are consistentwith excessive reaction forces and overuse prob-lems in the knee.' -"* ! Lower leg traumas range fromvarious contusions to peroneal neurapraxia and acutecompartment syndromes.' -'*'*' The majority of footand ankle injuries involve sprains and stress frac-tures associated with the repetitive demands of thesport and overzealous attention to plyometric con-ditioning.'^'

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2,4 Thoracic and Abdominal Injuries

Although thoracic or abdominal traumas werenot specifically noted in early studies concerningcollegiate athletes,'''^ a more recent and compre-hensive study indicates that thoracic, back and ab-dominal injuries account for 5 to 15% of all trau-mas in fast pitch competition,1^1 Of these, althoughlower back injuries account for only 7% of all cases,they represent 65% of thoracoabdominal cases. Col-lectively, the pelvis, hip, groin and buttock regionsare involved in 33% of injuries associated withthoracoabdominal cases,P^

Types of trauma include various contusions ofthe hip and pelvis, and groin and adductor strains,' ^Back trauma is typically limited to contusions andgradual-onset or overuse strains.l^l An isolated caseof posterior brachial neuropathy and axillary nervedamage has also been reported,'^^!

3. Aetiology

Due to the inherent nature of fast pitch softball,encompassing both high velocity pitching and splitsecond timing in the field, injuries often occur whenthe athlete collides with another individual or ob-ject, or attempts to slide into a base. These situa-tions are magnified when the quality of the playingsurface, the athlete's age and experience level, theexcessive physical demands and overuse associ-ated with the sport are also considered,l^''"'''*^'''^]

3,1 Collisions

Severe trauma can ensue from high impactforces encountered after collisions with players,balls, ground and fixed objects,l^^'^^l Of 165 casesreported during a single season of NCAA practices,42% of injuries were attributed to collisions in-volving player contact with equipment apparatusand balls (27%), playing surfaces (10%), compet-itors (4%) and various walls and fences (1 %),['] Ingame situations, collisions accounted for 75% of143 seasonal injuries, with equipment and ball con-tacts being the leading source of trauma (34%),followed by contact with competitors (24%), play-ing surfaces (16%), and wall and fence contact (1 %),

Although missed catches account for a substan-tial number of contusions to the face and fingers,^''^^of greater concern are injuries from direct ball con-tact while at bat. The windmill style of fast pitchSoftball can generate ball velocities ranging from65 to 113 km/h,I'^2^1 The high speed, in combina-tion with a ball of limited elasticity, high coeffi-cient of restitution, solid impact weight and highdynamic hardness, results in a substantial transferof force upon body impact, placing the batter ineminent danger of significant osseous and soft tis-sue trauma, [ '* ' ']

3,2 Base Running

At the collegiate level, injury associated withsliding into a base ranges from only 4% of traumaobserved during practice to 24% of all cases occur-ring during games,''' The majority of base runninginjuries are attributed to poor judgement, slidingtechnique and current stationary base design,'' "1

Poor judgement is typically observed in situa-tions where a player slides late into a base, as aresult of inattention to play or attempts to stretch abase hit, or when a player tries to reach a base dur-ing a run-down. These decisions often result in rapiddeceleration and abrupt contact with the anchoredbase,"'^'*^' Even during a normal sliding attemptor di veback, upper extremity and facial abrasions andlacerations occur from horizontal forces and cutane-ous shearing contact with the infield surface.''''^''^''Contusions to the chest, hips, buttocks and kneesresult from ground impact, due to greater verticalforces associated with feet-first sliding, and a poorhead-first sliding technique observed among lessexperienced players,''^"^'1 A significant numberof ligamentous disruptions, patellar subluxations,meniscal tears, acromioclavicular joint disorders,subacromial impingement syndromes (Stage I) andosteochondral fractures usually occur from unortho-dox joint and/or extremity positions during groundimpact,'''^'^''''''^^' and catching of cleats (e,g, plan-tar hyperflexion of the ankle),'''^^'J

The current style of sliding is thought to aggra-vate this situation. This style involves sliding feet-first into a base, with extreme momentum, in a

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66 Meyers et al.

semierect or sitting position. This enables a playerto rebound back up into an erect stance, readilypoised to stretch a hit into extra bases.''*'! It is instark contrast to the earlier supine form of slidingobserved in Softball's infancy, which optimised theamount of force absorbing body surface area in con-tact with the playing surface reducing the likeli-hood of impact injury.'^''^3' Unfortunately, the cur-rent style of sliding prevents the body from absorbingor dissipating impact forces, since there is a limitedbody surface area in contact with the playing sur-face and a minimal deceleration time.

In research into fast and slow pitch softball, sta-tionary base design has received a substantial amountof attention with little resolve. The standard 2 to4 inch high, foam-filled base, that is stabilised bysliding the central post into a stanchion or collarburied below the infield level, has been used fordecades.'''^''^^' Although the present base designhas been deemed problematic among sport medi-cine specialists, affordability of replacements in alimited revenue-generating sport remains a majorobstacle to introducing new designs with the po-tential to decrease base running injuries. In sum-mary, the combination of sliding into a base capa-ble of withstanding force impacts of up to 7000kg,in the currently popular semierect position, enhancesboth the rate and severity of injury.'^'''^l

3.3 Piaying Surfaces

A major objective, so as to for maintain an op-timal environment for athletes, is close attention toplaying or field surfaces. As previously mentioned,10 to 16% of injuries are attributed to surface char-acteristics that affect sliding, foot and cleat trac-tion, and ball dynamics."''*^' Soil characteristics,such as composition, moisture content and compac-tion, affect player stability and field hardness. Turf-grass characteristics, such as mowing height, grow-ing ability and durability, will affect traction, as wellas ball ground speed and rebound.' *-^ ' Improperselection and management of soil composites andturfgrass varieties leads to increased impact forcesand abrasiveness during ground collisions, and tountrue ball direction and bounce. The latter results

in physical impact trauma and to lack of player'stability, predisposing the player to sprains and lig-amentous disruptions.

3.4 Age and Experience

Well developed psychomotor skills are a prereq-uisite in maintaining optimal performance at batand in the field. When errors and concomitant in-jury in the field are reported, in many cases, theinjury is attributed to age and inexperienced play,where hand-eye coordination, sport-skill techniqueand split-second decision making processes havenot been adequately developed.' ^'' ^^J

At an early age, fast pitch injuries may occurfor several reasons. These include a high centre ofmass, immature skeletal development, an under de-veloped neuromuscular system and, simply, poorjudgement. A high centre of mass, due to the cyclicperiods of femoral growth, decreases a child's stabil-ity. Immature skeletal development, associated withincomplete epiphyseal plate closure, increases thepotential for Salter-Harris fractures, which can com-promise further bone growth. Inadequate proprio-ception, slow reaction and response time, and lackof agility are indices of an under developed neuro-muscular system typically observed with early ad-olescent athletes.

As the age and experience level of an athleteincreases, which is typically associated with a higheracademic level, one would expect to see a higherdegree of skill and a diminished likelihood of in-jury. During collegiate practice this would seem tobe the case, as 63% of injuries occurred to under-classmen, i.e. freshmen or sophomores, as opposedto 38% among upperclass or junior, senior and fifthyear athletes.'*! A similar pattern of injuries was ob-served during game situations, with 56% of injuriesoccurring in freshmen and sophomores compared with44% in junior and senior competitors."' However, noinformation was provided concerning the number ofathletic exposures or injury rate across class and aca-demic standing. Although traditionally upperclass-men usually experience more playing time and ath-letic exposure than lower classmen, the level ofacademic standing may not necessarily be associ-

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ated with experience level, since an increasing num-ber of freshmen are receiving more playing time atthe collegiate level,

3,5 Physicai Demands

Several studies have linked a substantial pro-portion of upper extremity injuries to inherent forcesof the underhand pitching motion and poor pitch-ing mechanics,"*'"^' An efficient, and therefore ef-fective, mechanical delivery results in ball velocitiesas high as 113 km/h, but at a cost of significant ante-rior capsule and biceps labrum stress.''^'"''^' This isaccompanied by extremes in internal and/or exter-nal rotation, flexion and extension of the glenohu-meral, ulnotrochlear and radiocarpal areas.''^'^'-^^]Additionally, opposing forces in the forearm struc-tures produce intense distal radioulnar pronationagainst a restricted brachioulnar range of motion(ROM), This results in formidable rotational torqueon cancellous and cortical bone structures,whichhave a limited cross-sectional area and an inabilityto resist shear forces,' '*' ' ^]

Maffet et al.t'^' divided the violent nature of thewindmill pitch into 6 phases: windup, phases 2 to 5as on a face on a clock (a counterclockwise arm move-ment from the 6 through 9 o'clock position), and afollow-through. In contrast, Barrentine et al,''^' con-sidered the pitching motion as the windup, stride,delivery and follow-through. These studies and oth-ers reflect the awkward positioning, rapid acceler-ation, extreme torque and abrupt deceleration forceswhich are distributed throughout the shoulder andupper extremities during the full ROM,' ^-*"' Fromthe hyperextension (at zero velocity) of the arm atthe glenohumeral joint during the windup,''*! limbacceleration continues to rapidly increase througha concerted effort involving the rotator cuff, the pec-toralis major, the anterior and posterior deltoidsand the serratus anterior musculature."^'^^'^'"*-'^ In-trinsic with the pitching motion, muscular intensitybuilds and ranges from 45 to 100% of maximalcapacity in a given performance,''^' During deliv-ery of a pitch, maximal compression forces at theelbow and shoulder regions have been recorded tobe as high as 70 to 98% of bodyweight,"*^' The

follow-through is no less severe, as the entire armacting as a lever, experiences pronounced deceler-ation as it typically contacts the lateral hip and thighregion prior to ball release,''*''^'^^'^"' As a conse-quence, and as observed with other high velocityand repetitive arm tasks,'' ''"^ ' articular failureand ulnar, humeral and metacarpal stress fracturesare common,'3'.34,35,45,681

3,6 Overuse

The physical requirements of the sport, coupledwith repetitive training and competition, usuallylead to what is referred to as overtraining syndrome(OTS),'^'-'"] The increasing prevalence of OTSamong fast pitch athletes has also been attributedto inconclusive evidence to clearly define the op-timal training zone for an athlete''^^' and to poorcommunication between player and coach,'*'! AJ..ditional factors reported to contribute to muscu-loskeletal compromise include the inherent hypo-vascularity of connective tissue and the limitedability of bone to remodel at an expedient rate tomatch the demands of the sport,' '' -'"^*' Althoughcoaches strive to balance optimal sport-specificworkload with adequate rest, tournament demandsfor all players may typically extend to 9 gameswithin 3 days, subjecting athletes to 18 to 36 hoursof actual playing time,'^^'

An excessive number of innings pitched in re-lation to the amount of recovery between starts hasalso been reported in the literature,'^'*' With anextensive schedule of batting practice, double head-ers, and both midweek and weekend games, pitch-ers may endure an average of 86 to 139 innings perseason leading to gradual-onset or overuse trauma,'^'It is not uncommon for pitchers to compete afteronly 2 days of rest or rotation compared with 3 to4 day rotations commonly observed in baseball,''*'The tremendous forces and torque produced by theunderhand windmill motion of pitching, in combi-nation with poor pitching mechanics and a signif-icant number of innings pitched, has led routinelyto articular arthralgia, instability in the arm, shoul-der and lower back regions, chronic NSAID useand time loss injuries in 45% of pitching staff dur-

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68 Meyers et al.

Table I, Recommendations for fast pitch Softball injury prevention

Check and maintain equipment on a continuous basis

Reinforce the need for athletes to wear protective clothing and gear, i.e. mouthpiece and sliding pads, at all times

Stay alert to the signs and symptoms of overtraining syndrome (OTS)

Vary day-to-day training routines to decrease repetitive musculoskeletal stress on the same joints

Stress the importance cf enhancing motor skills, with equal emphasis on speed and efficiency of movement in the field and on the basepath

Utilise drills that reinforce sport-specific, decision making processes to minimise mental mistakes

Minimise the use of indoor or gym floor facilities

Become familiar with infield and outfield playing surfaces, checking for cracks, sprinklers, stones and other surface obstructions

Provide and/or maintain padding, screens and barriers for all walls, backstops, rails, dugouts and immovable objects in the field of play

Attend coaching and sports medicine seminars to enhance training and conditioning techniques

ing a single season.f ''*' ' Due to serious concernamong sports medicine specialists, and the limitednumber of studies in this area, further research isclearly warranted.

3,7 Contributory Factors

Other contributory factors have been mentionedwith regard to ulnar and radial neuropathies, compart-ment syndromes, enhanced overload to the shoul-der's static stabilisers and fatigue fractures. Theseinclude inadequate attention to bilateral muscu-loskeletal function, muscular endurance and flexi-bility, and abrupt changes in pitching technique.Gender differences in lean body mass, technique,strength, handgrip size and ligamentous laxity havealso been documented,''''' ' '' '*''' "^^] Additional con-tributory factors reported include stenosis in thenarrow fibrotic arch of the triceps, neuralgia, fusi-form neuromas, radial nerve scarring and idiopathicjuvenile

4. Prevention

The majority of fast pitch softball injuries areavoidable, with numerous opportunities availableto instill measures of safety throughout the sport.Specific attention to a safer playing environment,coaching and player education, and sport-specifictraining and conditioning would reduce the risk,rate and severity of fast pitch trauma. These effortswould be especially salient at the younger levels ofcompetition. Recommendations to prevent injuriesin fast pitch softball are summarised in table I,

4,1 Safer Piaying Environment

Although 53% of fast pitch game injuries occurin the infield, 46% of documented trauma caseshave occurred on outfield or natural and artificialgrass surfaces, necessitating that equal attention begiven to all playing surfaces.''' Initially, attention tofield surfaces begins with soil properties and turf-grass selection. Following construction, maintenanceof the playing surface should focus on field hard-ness, turfgrass cutting height, frequency of mow-ing, clipping removal, soil moisture content, irriga-tion and drainage control, aeration and avoidanceof excessive wear,''**- ' '

Besides natural and field conditions, other play-ing environments pose some concern. In responseto foul weather, many coaches choose to use indoorfacilities to maintain practice schedules. In a recentstudy, players experienced a greater number of prac-tice injuries (53%) and a higher injury rate (3,5) onnongrass surfaces, i,e. gym floors, compared withnatural grass (23% and 2,0, respectively),'" The lim-ited floor space, harder playing surface and poorerball visibility and contrast contribute to an increasedoccurrence of blunt traumas resulting from playercollisions, falls and greater ball speed and bouncethan that observed with normal field conditions.

Additional attention to padding of walls, back-stops, rails and dugout areas has been suggested todecrease the number of collision injudes.'^'^^' Elimi-nating the use of the on-deck circle and installingprotective screening and barriers for dugouts andcoaching boxes have also been proposed, because



of the continual incidences of direct ball and batcontact traumas to both players and coaches."'^'"Lastly, recessed, low-profile or breakaway bases,as well as improvements in base installation, shouldbe considered to reduce the trauma associated withbase

4.2 Coaching and Player Education

A greater emphasis on coaching and player ed-ucation has been recommended as a measure to re-duce the frequency of injury in this sport.' - ' ^l Aspreviously mentioned, several studies have linkeda number of both upper and lower extremity trau-mas to poor techniques or mechanics.'' '*' ' ' ^]Others have attributed a substantial proportionof injuries, i.e. fractures, to gradual-onset or over-use, or to a lack of attention to protective equip-ment [8,30,31,34,45,86,87] jj, 59 to 91% of head and fa-cial injuries a mouthpiece was not worn."!

In regards to gradual-onset or overuse injuries,coaches should be cognisant of the signs and symp-toms of OTS, a condition exacerbated by repetitiveoveruse and minimal recovery and/or rest.'^"'^''Although predicting OTS is often difficult and in-conclusive with subclinical traumas, over 94 phys-iological, psychological, immunological and bio-chemical markers associated with this increasingproblem in sports have been reported.'^'-^^"^''] Pro-gression of training from a normal adaptive micro-trauma (AMT) to subclinical injury may be mini-mised by varying day-to-day training routines todecrease repetitive musculoskeletal stress on thesame joints.'^'-'^l Players with a seasonal historyof chronic arm pain, muscular fatigue, diminishedperformance or showing sudden changes in the bio-mechanics of throwing or pitching so as to alleviateprodromal discomfort are demonstrating hallmarksigns of overt orthopaedic trouble.' ^^'"' l Thesesymptoms are usually suggestive of a stress frac-ture.' ^^'''^'' Breaking the repetitive cycle of com-petitive overuse, shoulder pathology, minimal re-habilitative and recovery time, and excessive useof steroids and analgesics should be a primary goalto minimise further career-ending articular insta-bility."^'

Although many programs are conducted withlimited coaching staff, special attention to motorskills, with equal emphasis on speed and efficiencyof movement in the field and on the basepath, ishighly recommended.''* '''*"^ ' Using drills that re-inforce sport-specific, decision making processesshould minimise mental mistakes and reduce theincreasing number of player' collisions.'^'''^'*'''l Ul-timately, a greater understanding of anatomy andsport physiology, along with concomitant attentionto injury prevention through more careful planningof practices, player rotation, sport-skill techniqueand protective equipment for coaches and players,should result in a lower incidence of significanttime-loss cases.' '

4.3 Conditioning

Sport-specific conditioning is considered to bethe cornerstone of todays successful athletic pro-gram. As games become faster and players morephysical, it is imperative to design programs thatemphasise a combination of power, acceleration,flexibility, technical skill, functional capacity andinjury prevention.'^^'""']

Since 47 to 49% of all practice injuries are at-tributed to noncontact pitching and throwing situ-ations,''"'*^'^^' specific attention to upper torso,shoulder and rotator cuff musculature should be apriority.''*'^' This is particularly important amongfemale athletes, who have an inherently lower per-centage of lean body mass and, subsequently, lessstrength than male competitors."^-^'*!

Despite its popularity, only limited informationon specific training routines for fast pitch softballhave been published.'^''^^' Since softball is consid-ered an intermittent-activity sport utilising up to80% adenosine triphosphate-creatine phosphate(ATP-PC),' '*J enhancing speed-endurance throughhigh intensity interval training has been recom-mended.'^^' This involves year-round conditioningthat especially focuses on improving sport-specificarm and back strength, leg power, explosive move-ment and a full ROM.'5''0'1 Training volume, in-tensity, recovery, duration and activities are variedas the athlete moves through a series of phases that

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70 Meyers et al.

progress from general preparation through basicstrength, functional strength, power, maintenanceand active rest.'^^'"^'

Although isotonic, isokinetic and plyometricconcepts have been successfully applied in varioussports, results among throwing athletes are equiv-ocal. In one study, greater increases in shoulder powerwere observed with isokinetic training than withplyometrics, but with insignificant effects on func-tional performance,"""' Others have noted substan-tial closed-chain development of functional powerin the trunk and in the upper and lower extremitiesusing plyometric and isotonic techniques in the con-ditioning progranu'^^''^^' Optimally, the goal is tocombine all 3 forms of work with adequate rest toachieve a high degree of functional capacity on thefield of play,"0'''"2]

Incorporation of an off-season or preseason pro-gram using a progressive combination of long andshort throws has been successfully used in base-ball,''"^' This type of early throwing program would bebeneficial for all softball positions. It could easilybe adapted to the underhand windmill style of pitch-ing to enable the shoulder musculature to meet theimpending demands of fast pitch competition,'"*^-'"?'Since specific training and rehabilitation modali-ties are beyond the scope of this article, the readeris referred to excellent reviews on the topic,'' ^^'"J'

5. Conclusion

Fast pitch competitors experience a significantlevel of injury. Although only limited preventativemeasures exist which will totally eradicate compet-itive injury, even moderate attention to preventa-tive recommendations may decrease the number andseverity of problems (see table I), Of greater con-cern, is the underestimation of trauma because ofthe limited body of knowledge currently availableon this sport,'^' For example, out of 902 NCAAmember institutions fielding approximately 500 to600 teams, injury surveillance data are only avail-able on 10 to 15% of fast pitch programs.'^' Themajority of other reported injuries have been lim-ited to isolated case studies, studies of small samplesizes and hospital records, and represent a modest

fraction of participating athletes.'2'^''^"''"'*' There-fore, broadening efforts and funding to increaseaccessibility of surveillance systems to a greaternumber of programs would provide a clearer andmore accurate picture of the prevalence of injuryin this sport.

There is also an increased need for research thataddresses optimal management and playing surfacecharacteristics for fast pitch softball,''**' Compari-son of various turfgrass properties with softball shoeand cleating systems would enhance our understand-ing of more effective field grass selection and du-rability, resulting in a decrease in traction injurieswithout compromising quality of play. Comparisonof soil mixtures to determine optimal texture andmoisture retention would lead to better player sta-bility, truer ball speed, bounce and direction, andwould minimise surface hardness and abrasiveness.These efforts would result in a pronounced decreasein the number and severity of collision and slidinginjuries.

Continued research should be directed towardboth preventive aspects of sports medicine andpost-injury care. Although studies have quantifiedthe specific phases and muscle firing activity of thethrowing'*^''"^''"*' and pitching motion,''*'''''*^-''^'more accurate recognition and diagnosis of injuryis needed. In addition, conditioning and rehabili-tation protocols that specifically impact on thesuccessful functional outcome of an injury in thissport have not been firmly established and warrantfurther investigation,"''' Finally, additional effortsshould be directed towards comparing institutionsand programs that address medical, coaching andenvironmental concerns previously outlined withthose programs that lack preventive mechanisms.Results from this comparison would provide a clearerpicture of injury causation and effective manage-ment procedures, leading toward safer participa-tion and successful player development,

Aci


uations of the authors and do not represent the views of theofficers, staff or membership of the NCAA.

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Correspondence and offprints: Dr Michael C. Meyers, Hu-man Performance Research Center, Department of Sportsand Exercise Sciences, POB 60216, West Texas A&M Univer-sity, Canyon, TX 79016, USA,

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