Elbow Injuries in Adolescent Throwers: Is It Bone, Is It Soft Tissue?

Transcription

1 Elbow Injuries in Adolescent Throwers: Is It Bone, Is It Soft Tissue? Gregory N. Lervick, MD Instructor, Shoulder and Elbow Surgery Minnesota Orthopedic Sports Medicine Institute (MOSMI) Fellowship Program Twin Cities Orthopedics Edina, MN

2 Disclosure No relevant financial relationships to disclose.

3 Overview Epidemiology Anatomic factors Activity factors Presentation Evaluation Imaging Specific diagnoses / treatment

4 Background Elbow pain common in young throwers Lyman et al, AJSM pitchers age % of all pitching appearances 28% of all pitchers during season Increased incidence with: Higher pitch count Curveball (shoulder pain) Slider (elbow pain) Provided basis for USA baseball recommendations regarding pitch counts and types

5 Background Elbow pain common in young throwers Makhni et al, AJSM players in NY and NJ 23% reported prior overuse injury Only 26% of pitchers and 20% of players reported their arm never hurt during or day after throwing 46% reported being encouraged to throw through pain at least once

6 Background Olsen et al, AJSM adolescent pitchers who underwent shoulder or elbow surgery 45 controls (healthy pitchers) Standardized survey

7 Background Olsen et al, AJSM 2006 Injured group: More often starting pitcher Threw in more showcase events Higher velocity Pitched with arm pain or fatigue Used NSAIDs / icing Taller Heavier

8 Background Olsen et al, AJSM 2006 No difference between groups: Private pitching instruction Coach s concern Pitcher s self-rating Exercise programs Relieving frequency Pitch types

9 Background So what about injury risk?: Fleisig et al, AJSM youth pitchers (9-14 yr old) 10 year prospective study 3 groups: Injured (surgery or retired (shoulder or elbow)) Successful (pitched > 4 yrs) Short-term (pitched < 3 yrs) 3 proposed risk factors: High volume pitching Throwing curveballs before age 13 Pitching and playing catcher in same season / game

10 Background Fleisig et al, AJSM 2011 Results: Cumulative injury incidence: 5% Remaining athletes: 65% short term 30% successful 2.2% were still pitching at 10 year follow up Short term and successful pitchers had similar injury risk Pitching >100 innings in single year = 3.5 X more likely to be injured No relationship to curveball at young age or playing catcher

11 Anatomic factors Carrying angle = valgus Bony structure (olecranon) provides stability between 0-20 beyond 120 flexion Soft tissue constraints (anterior bundle UCL) provide stability between flexion

12 Developmental factors Underdeveloped musculature / core strength Small hand (grip) Immature skeleton Rapid growth Physes may be more at risk

13 Athletic factors Tremendous forces during throwing Angular velocities = 3000 deg/sec Valgus forces = 64 N-m on ulnar side Compression = 500 N at radiocapitellar articulation Cain et al, AJSM 2003

14 Athletic factors Large valgus load with combined rapid extension: Tensile stress on ulnar (medial) side Shear stress posteriorly Compression laterally Valgus extension overload syndrome Cain et al, AJSM 2003

15

16 Presentation Typically late-cocking / early acceleration phase May be gradual or sudden Training regimen Pitch type Pitch number Recent changes Rest periods Teams / leagues / events

17 History Onset: sudden v. gradual Bruising / swelling Pain location Timing of symptoms Other complaints Mechanical symptoms Ulnar paresthesia Shoulder Hip/knee/lower extremity Spine Prior treatment surgical nonsurgical

18 Physical examination Don t start with the elbow, finish with it Core strength, body habitus, posture Shoulder examination Scapular control GIRD evaluation Evaluate bilateral Look for differences Osseous vs soft tissue changes Knee/hip/trunk

19 Physical examination Elbow examination Posture, carrying angle Swelling, effusion (look in the soft spot) Ecchymosis Location tenderness Active and passive ROM Ulnar nerve examination Specific tests Static valgus stress Valgus extension overload test Milking maneuver Flexor pronator assessment

20 Plain radiographs Orthogonal views (AP / lateral) Contralateral views necessary when skeletally immature Physeal evaluation Widening Persistence of physes Avulsion fractures Fragmentation (medial side) Capitellum Lysis Loose body formation Consider 45 degree oblique views (sensitivity poor) Degenerative change / posteromedial osteophyte formation suggests chronicity

21 MRI Use to evaluate for: Osteochondral injury (OCD of capitellum, other chondral change, loose body formation) Ulnar collateral ligament (UCL) avulsion or detachment Physeal stress reaction (determine level of severity, reactivity) Use contrast in chronic or subacute settings when evaluating UCL Good sensitivity / specificity Cain et al, AJSM 2003

22 MRI Hurd et al, AJSM asymptomatic male baseball pitchers Bilateral MRI 65% asymmetric UCL thickening 61% posteromedial subchondral sclerosis 35% posteromedial osteophyte 17% posteromedial chondromalacia 4 had mild edema at sublime tubercle Take home point: abnormalities exist even when symptoms don t

23 The injury spectrum Epidemiology in adolescents is not well understood Injury patterns are variable What necessitates treatment? Prolonged pain despite rest / modification Muscle fatigue and diminished performance may suggest an underlying injury Don t ignore; use common sense Pure ligament sprains are uncommon in the youngest throwers The younger the athlete, and more acute the symptoms, think bone or cartilage involvement until proven otherwise!!

24 Differential diagnosis Medial epicondyle apophysitis Ulnar collateral ligament injury: sprain, avulsion Olecranon stress reaction / fx / apophysitis Capitellum osteochondritis dissecans (OCD) Ulnar neuritis Flexor pronator strain

25 Medial epicondyle apophysitis little leaguer s elbow Stress reaction of the medial epicondylar physis Most common cause of elbow pain in the adolescent Gugenheim et al, AJSM 1976 Often gradual onset and persistent Common in rapid growth years, Coincides with: Increased participation Longer duration Higher training intensity Changes in pitch type

26 Adolescent elbow Medial epicondyle apophysitis Active rest; relative rest May be prolonged Address other issues: GIRD, core strength, etc. What about return to play? Recurrence possible Consider position change (temporary) MRI may helpful in assessing level of reactivity / healing Will resolve with time and skeletal maturation What happens if it leads to displacement??

27 Medial epicondyle fracture Displaced fxs controversial No clear consensus on what amount of displacement is acceptable Low interobserver agreement Pappas et al, JBJS-A 2010 Likely very little in a thrower even a small amount could create problems in the long term More proactive with these injuries Fix rigidly and early, and rehab progressively Goal: physeal closure

28 Ulnar collateral ligament (UCL) injury Is it the same injury in adolescents? Anecdotal observations More often acute onset Bony avulsion injuries / pole detachments Should treatment protocol be extrapolated from the MLB experience? When is surgical treatment indicated / warranted?

29 UCL: nonsurgical treatment Rettig et al, AJSM % success, avg age 18 yrs, return avg 24 weeks Makes sense in the very young adolescent Bracing Temporary rest Early rehabilitation Return based on symptom resolution Prolonged immobilization not advised What about an avulsion in the older adolescent? Natural history felt to be poor Cain et al, AJSM 2003 MRI helpful in determining Acute v. chronic Anatomic location of injury

30 UCL: surgical treatment Petty et al, AJSM high school age throwers Mean age 17 yrs (16-19) Avg follow up 35 mos. 63% acute onset 33% had evidence of bony detachment UCL reconstruction with autograft 74% return to sport No information on timing of return to sport Examined 6 potential risk factors Avg of 3.1 risk factors in treatment group

31 UCL: surgical treatment Savoie et al, AJSM pts, mean age 17 yrs (14-22) Failed initial nonsurgical management 85% throwers 69% Acute onset Primary repair Intra-operative decision Based on injury location, tissue quality 93% good-excellent results 58/60 returned to high school or collegiate sports 56/60 returned to sport within 6 mos following surgery

32 UCL: surgical treatment Hodgins et al, AJSM 2016 NY state database (10 yrs) Volume of UCL reconstructions increased 193% Rate per 100,000 tripled ( ) Significant trend particularly in yr olds 400% increase in concomitant ulnar nerve treatment Erickson et al, AJSM 2015 Pearldiver private payer database Avg annual overall growth rate 4.2% (9.1% in yr old age group) More common in southern US

33 Olecranon apophysitis / fracture May present with vague or even medial elbow pain Often presents as a persistently open physis Scant reports in the literature May displace acutely Successful nonsurgical treatment has been reported Nuber / Diment, CORR 1992 Recommended treatment is internal fixation with intramedullary screw Rettig et al, AJSM 2006 Paci et al, AJSM 2013

34 Capitellar OCD (Osteochondritis dissecans) Separation of a segment of bone and cartilage Mean age of onset: Males > Females Most commonly involves the dominant arm May be bilateral in 5-20% of patients Cause multifactorial: Microtrauma: compressive lateral force Ischemic: poor epiphyseal blood supply

35 Capitellar OCD (Osteochondritis dissecans) Pain is the most common symptom Decrease in ROM Usually lack terminal extension Less commonly a loss of flexion Pronosupination typically preserved Mechanical symptoms Indicative of loose body or partially displaced lesion

36 Capitellar OCD (Osteochondritis dissecans) Plain films important for screening Poorly accurate for this diagnosis If diagnosis suspected on history / examination, MRI is recommended Very accurate Contrast not necessary, but may help determine lesion stability

37 Capitellar OCD (Osteochondritis dissecans) Nonsurgical treatment Stable lesions with intact cartilage and in situ subchondral fragments Active rest Address other issues Return based on functional criteria Imaging criteria not agreed upon Success variable Takahara et al, AJSM 1999 Takahara et al, JBJS-A 2007

38 Capitellar OCD (Osteochondritis dissecans) Surgical treatment Persistent or worsening symptoms despite compliance with nonsurgical treatment Evidence of instability of disrupted articular cartilage Arthroscopic vs. open methods Loose body removal Excision +\- drilling or abrasion chondroplasty Microfracture Fragment fixation +\- bone graft Osteochondral plugs (OATS, mosaicplasty) Wedge osteotomies

39 Capitellar OCD (Osteochondritis dissecans) OATS/mosaicplasty Autologous graft from distal femoral cartilage Open procedure Gradual incorporation Arthroscopic treatment Debridement v. microfracture Fibrocartilaginous repair Long term data pending Both appear successful in short to medium term Iwasaki et al AJSM 2009 Byrd et al, AJSM 2002 Wulf et al, AJSM 2012

40 Ulnar neuritis Potential causes Traction from valgus stress Flexor-pronator hypertrophy Compression from adhesions Anconeus epitrochlearis Li et al, Orthopedics 2012 Friction due to dynamic subluxation Rettig/Ebben, AJSM 1993 Uncommon as isolated dx Carefully consider underlying pathology (UCL) Treatment most commonly nonsurgical

41 Flexor-pronator strain Flexor-pronator mass provides dynamic support to valgus stress Sisto et al, AJSM 1987 Park / Ahmad, JBJS-A 2004 Typically mild to moderate muscular overuse Symptoms similar to UCL insufficiency Medial pain, late cocking, early acceleration Generally responds to nonsurgical management May signal underlying structural problem Think of other potential diagnoses

42 Instruction / monitoring Important to discuss with any young thrower and his/her parents Parents are generally supportive and want to do the right thing Coaches and trainers have better resources and more awareness Work with them! USA baseball recommendations Pitch count Pitch type Age dependent Be familiar with these recommendations

43 Summary Elbow pain common in the adolescent thrower Elbow injuries result from large valgus and extension moments Musculoskeletal anatomy unique in young thrower Underdeveloped core, small anatomy Bone (physes) and cartilage at risk Proper instruction and monitoring important Medical evaluation appropriate when: Pain does not resolve despite brief rest Signs of acute injury: bruising, swelling, ROM loss

44 THANK YOU