ATHLETES: OVERUSE MRI of Overuse INJURIES VERY COMMON Injury in the Elite Athlete • Muscle William B. Morrison, M.D. Associate Professor of • Joints Radiology Thomas Jefferson • Tendon University Hospital Philadelphia, PA USA • Ligament • Bone
How is this Relevant to My Practice? • High performance athletes get similar injuries as ‘regular’ people… but: – More of them, & at a younger age MUSCLE / SOFT TISSUE – More commonly imaged – Secondary gain involved INJURY • All the cases here are high performance athletes – but most injuries are conventional • Exceptions – Some weird sport-specific patterns of stress and other injuries – Acute injuries as opposed to overuse
•Overuse –DOMS Muscle Injury Delayed Onset Muscle • Acute injury Soreness (DOMS) – Tendon – Myotendinous junction • All athletes are susceptible if they – Muscle belly change training regimen • Athletes tend to work out intensely – leads to muscle injury • Rarely imaged (“no pain no gain”) – Weightlifting / aerobic exercise – 24hr later – soreness – Can be severe, even look like a tear
1 Acute Muscle Injury
• Direct → muscle belly, esp quadriceps T2 – esp rugby, football
• Indirect → myotendinous junction – eccentric contraction – sudden acceleration / DOMS: Lateral gastrocnemius deceleration Finding can be subtle, even with T2 and fat sat
Professional football player Acute Injury – T1 Quadriceps hematoma Muscle belly injury Myotendinous Unit Hit with helmet
• Myotendinous Junction – ‘weak link’ of normal myotendinous complex T2 – Common place for injury – Most common mechanism: eccentric contraction (muscle lengthens and contracts at the same High time) T1 = blood
Gastrocnemius tear: Grade 1 Muscle Strain “V” sign • Ill-defined edema
T2
T1 STIR Weishaupt D, JCAT 2001; 25:677
2 Gd Gd can help identify Grade 2 Muscle Strain subtle muscle injury AKA “Partial Tear” STIR
Professional baseball player Grade 1 strain Sartorius m.
Marathon Runner Quadratus Femoris Strain
Small Grade 2 Strain – NFL Player
High performance athletes often get routine injuries in unusual locations
Grade 3 Muscle Strain Grade 3 Strain • Complete tear Rectus femoris – Fluid, blood common – Retraction – balled up muscle may be perceived as a mass – Degree of dysfunction varies • Hamstrings, rectus femoris, tibialis anterior – loss has little effect on ADL STIR perfomance
3 Sportsman’s Hernia
Adductor avulsion Pubic symphysis capsule injury Sportsman’s Hernia
Rectus abdominis strain ::Groin pain medially ::Actually a ‘grab bag’ of diagnoses -Adductor injury -Pubic symphysis inj -Rectus abdominis strain -actual hernia
Chronic Injury Marathon Runner Bone resorption Loss of cortex
Looks like clavicular osteolysis Corresponding MRI
Edema only / predominantly at distal clavicle Classic in Weightlifters
Other Muscle Pathology
Dysfunction related to nerve impingement
Compartment syndrome Clavicular Osteolysis
4 Radial Tunnel Syndrome Compartment Syndrome
Gd helps find subtle areas of muscle involvement! • Confined fascial compartment – Lower leg > thigh – Most common: anterior compartment • Acute and chronic forms – Acute: tibial fx, hematoma, vascular injury, infection Elbow nerve impingement – Chronic: Muscle hypertrophy / overexertion syndromes -Many types • Increased compartmental pressure (>30mm Hg) -Etiology • Decreased bloodflow into compartment ::muscle hypertrophy (wt lifters) – Clinical: pain/swelling, weakness, decreased sensation ::upper extremity endurance athletes (esp tennis) • Late: Muscle infarction T2 FSE fatsat
Chronic Exercise-induced Compartment Syndrome Anterior compartment
Pre-Gd Bursitis
Gd can help show subtle variations in muscle vascularity
Post-Gd
Adventitial Bursitis
Friction related Exquisitely painful Activity-specific locations TENDONS
Professional Ballet dancer
Also note stress fx of sesamoid
5 TENDON TENDINOSIS PATHOPHYSIOLOGY • Thickening, increased signal (T1, PD, T2)
• Degeneration Example of friction: Distal biceps -primary (overuse injury) Mechanical-pronation leads to impingement between radius -direct frictional effect and ulna • Hypovascular-critical zone – Tendons without sheaths are susceptible • Achilles, biceps, cuff, etc. – Between myotendinous jct and insertion • ‘Normal tendons don’t tear’ Distal biceps -esp in weightlifters 2
TENDON TEAR LATERAL EPICONDYLITIS Adjacent marrow edema -Chronic, severe, refractory cases
Epicondylitis ::Especially in racquet / club sports COMPLETE TEAR: USUALLY ::Lateral= tennis elbow ASSOCIATED WITH RETRACTION – e.g., biceps: retracts, bulging muscle (‘popeye’ arm) Muscle edema (esp ECR brevis)
IMPINGEMENT MEDIAL EPICONDYLITIS Rotator Cuff • “Golfer’s elbow” Tendinosis and Tear
•Lateral acromial downslope: –Predisposes to impingement –Esp. common in overhead throwing sports
TEAR 2
6 --Impingement is nearly Undersurface Partial Lesions at the Tendinosis always involved “watershed zone” Hypoxic Degeneration --Underlying degeneration Thickness Tear --“Acute tear” extremely uncommon
Professional basketball player
Lesions at the Tendinosis “watershed zone” Tendinosis Mucoid Degeneration Painful Enthesopathy
Edematous spur =high likelihood of sx
Professional basketball player
Patellar Tendinosis / Tear Tendinosis / Tear Pro Basketball Player
7 Iliotibial Band Friction Syndrome Long Distance Runner
OVERUSE INJURIES IN ADOLESCENT ATHLETES
Delayed Union of Apophyses Medial Apophysis Stress
Avulsive Stress Ischeal Apophysis Old Osgood-Schlatter Gymnast Extensor mechanism pathology AKA “Jumper’s knee” Esp. common in basketball
8 Cartilage Lesions Microfracture – NBA Player
JOINTS
Medial compartment symptoms prevent play
S/P MICROFRACTURE 7 MONTH FOLLOW-UP 13 MONTHS LATER
Playing without Recurrent symptoms symptoms
OSTEOCHONDRAL LESIONS OSTEOCHONDRAL LESION OF THE TALUS Panner’s disease Esp. in basketball Esp. in adolescent pitchers
35 month follow up -interval detachment of Chronic osteochondral injury of capitellum fragment Underlying focus of AVN
9 OCD KNEE OCD phalanx Detached
Ballet Dancer
Professional Baseball Player Synovitis in Elbow Plicas and Bodies
POSTERIOR SPURS, INTRA- Posterolateral Elbow Plica ARTICULAR BODIES Baseball Pitcher
10 ANKLE JOINT Impingement
Joint Impingement Anterior impingement: and Instability large spurs limit dorsiflexion -esp in soccer, kicking sports
Anterolateral Impingement Posterior Impingement Esp. in ballet “meniscus syndrome” “Os Trigonum Syndrome”
-following tear of lateral -big os ligaments -fluid at interval -scar tissue forms in recess -leads to impingement, cartilage -cystic change erosion, pain
Hip Impingement Posterior Labral Tear Basketball Player Chronic Unidirectional Posterior Instability
Subluxation
11 Chronic Multidirectional Instability Combined Anterior and Posterior Instability
Capsular Injury ANTERIOR DISLOCATION
POSTERIOR CAPSULAR OSSIFICATION “BENNETT LESION”
Soccer – capsular “Turf Toe” injury superomedial
Football players -esp. due to artificial turf -Tear of plantar plate 1st MTP -Often acute on chronic
DORSAL HOOD INJURY Boxer LIGAMENTS FASCIA
12 ELBOW MCL INJURY T T
NORMAL MCL partial tear “T sign”
CHRONIC INJURY
PLANTAR FASCIITIS Flexor tendon pulley injury Esp. in runners Acute on chronic
Esp. common in rock climbers
Plantar Fascia Medial Tibial Stress Tear Syndrome • AKA “shin splints” • Avulsive injury medial tibial myofascial attachment • Running, overuse • Fascial or periosteal edema along anteromedial tibia • Occasional marrow edema • Most common: normal MRI T2
Anderson MW. Radiology 1997; 207:826
• Fatigue: ‘people in fatigues’ – Normal bone undergoing BONE abnormal stress – Young people • Insufficiency – Abnormal bone (eg, osteoporotic), normal stresses – Older population
Etiology of Stress Fracture Stress
40 Response • During early phase of a new 35 no linear component activity, muscle 30 steadily increases 25 muscl e strength 20 bone • Bone must 15 undergo a phase of 10 osteoclastic 5 resorption first 0 12345678 “At risk period” weeks
Stress Fracture Stress Fracture
Late – Propagation across shaft
Atypical locations: periostitis may be mistaken for tumor
14 Tibial Stress Fracture Multiple Foci Stress Classic in runners Fracture
Late – Thick periostitis
18 year old male Fatigue fracture Classic Fatigue Fracture Persistent pain in hip 2nd Metatarsal Shaft History of recent increase in activity
Olecranon stress in gymnast Atypical Sports-specific Locations
15 GYMNAST WITH DISTAL RADIAL / ULNAR PHYSEAL STRESS Capitate stress Bilaterally Gymnast
STRESS Humeral stress pitcher RESPONSE Ballerina
Stress forearm in female softball Stress femur player nba
16 Sesamoiditis AVN Sesamoid Likely an end stage of stress
T1 T2
-Hyperemia likely due to chronic repetitive injury -Prob along spectrum of stress, AVN -Sesamoid high on T2, STIR surrounding ST edema -Mostly preserved T1 signal T1 T2
AVN metacarpal head (post op) Pro boxer QUESTIONS?
Dynamic Gd demonstrates viability of remaining bone
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