Bryan English Medical Director Middlesbrough Football Club. Member of Technical Advisory Group in Sports Science. The English Institute of Sport - Terminology and classification of muscle injuries in sport: a Munich consensus statement (6th MuscleTech Network Workshop) 14th October, Barcelona

1. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Muscle Injuries:
The Munich Consensus Classification System
Bryan English
Peter Ueblacker
Lutz Hänsel
Hans-Wilhelm Müller-Wohlfahrt

2. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Relevance of athletic muscle injuries
• 31% of all injuries in professional football/soccer
• cause 27% of absence times in football/soccer
• most frequent injury in track and field, basketball etc.
(Malliaropoulos AJSM 2011, Borowski AJSM 2008)
• 49% of all injuries in American Football
(Feeley AJSM 2008, Brophy AJSM 2010)

3. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Previous classification systems
O’Donoghue 1962
Ryan 1969
(initial for quadriceps)
Takebayashi 1995,
Peetrons 2002
(ultrasound-based)
Stoller 2007
(MRI-based)
Chan 2012
(MRI-/ultrasound-based)
Grade I
No appreciable tissue
tearing,
no loss of function or
strength,
only a low-grade
inflammatory response
Tear of a few muscle
fibres,
fascia remaining intact
No abnormalities or
diffuse bleeding with/
without focal fibre rupture
less than 5% of the
muscle involved
MRI-negative
= 0% structural damage
Hyperintense oedema
with or without
hemorrhage
Includes
Site of injury:
-proximal,
-middle
-distal
Pattern:
-intramuscular
-myofascial
-myofascial/perifascial
-musculotendinous
-combined
Severity:
-comparable to Stoller
Grade II
Tissue damage,
strength of the
musculotendinous unit
reduced,
some residual function
Tear of a moderate number
of fibres,
fascia remaining intact
Partial rupture: focal fibre
rupture more than 5% of
the muscle involved
with/without fascial injury
MRI-positive
with tearing up to 50% of
the muscle fibres.
Possible hyperintense
focal defect and partial
retraction of muscle fibres
Grade III
Complete tear of
musculotendinous unit,
complete loss of function
Tear of many fibres with
partial tearing of the fascia
Complete muscle rupture
with retraction, fascial
injury
Muscle rupture = 100%
structural damage.
Complete tearing with or
without muscle retraction
Grade IV
X Complete tear of the
muscle and fascia of the
muscle –tendon unit
X X X

4. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Previous classification systems - Limitations
O’Donoghue 1962
Ryan 1969
(initial for quadriceps)
Takebayashi 1995,
Peetrons 2002
(ultrasound-based)
Stoller 2007
(MRI-based)
Chan 2012
(MRI-/ultrasound-based)
Grade I
No appreciable tissue
tearing,
no loss of function or
strength,
only a low-grade
inflammatory response
Tear of a few muscle
fibres,
fascia remaining intact
No abnormalities or
diffuse bleeding with/
without focal fibre rupture
less than 5% of the
muscle involved
MRI-negative
= 0% structural damage
Hyperintense oedema
with or without
hemorrhage
Includes
Site of injury:
-proximal,
-middle
-distal
Pattern:
-intramuscular
-myofascial
-myofascial/perifascial
-musculotendinous
-combined
Severity:
-comparable to Stoller
Grade II
Tissue damage,
strength of the
musculotendinous unit
reduced,
some residual function
Tear of a moderate number
of fibres,
fascia remaining intact
Partial rupture: focal fibre
rupture more than 5% of
the muscle involved
with/without fascial injury
MRI-positive
with tearing up to 50% of
the muscle fibres.
Possible hyperintense
focal defect and partial
retraction of muscle fibres
Grade III
• non-structural injuries not mentioned or not differentiated
Complete tear of
musculotendinous unit,
complete loss of function
• not comprehensive
Tear of many fibres with
partial tearing of the fascia
Complete muscle rupture
with retraction, fascial
injury
Muscle rupture = 100%
structural damage.
Complete tearing with or
without muscle retraction
Grade IV
X Complete tear of the
muscle and fascia of the
muscle –tendon unit
X X X

5. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Previous classification systems - Limitations
O’Donoghue 1962
Ryan 1969
(initial for quadriceps)
Takebayashi 1995,
Peetrons 2002
(ultrasound-based)
Stoller 2007
(MRI-based)
Chan 2012
(MRI-/ultrasound-based)
Grade I
• no differentiation within structural injuries
> Injuries with different prognosis are diagnosed
No appreciable tissue
tearing,
no loss of function or
strength,
only a low-grade
inflammatory response
Tear of a few muscle
fibres,
fascia remaining intact
No abnormalities or
diffuse bleeding with/
without focal fibre rupture
less than 5% of the
muscle involved
MRI-negative
= 0% structural damage
Hyperintense oedema
with or without
hemorrhage
Includes
Site of injury:
-proximal,
-middle
-distal
Pattern:
-intramuscular
-myofascial
-myofascial/perifascial
-musculotendinous
-combined
Severity:
-comparable to Stoller
Grade II
Tissue damage,
strength of the
musculotendinous unit
reduced,
some residual function
in one grade
Tear of a moderate number
of fibres,
fascia remaining intact
Partial rupture: focal fibre
rupture more than 5% of
the muscle involved
with/without fascial injury
MRI-positive
with tearing up to 50% of
the muscle fibres.
Possible hyperintense
focal defect and partial
retraction of muscle fibres
Grade III
Complete tear of
musculotendinous unit,
complete loss of function
Tear of many fibres with
partial tearing of the fascia
Complete muscle rupture
with retraction, fascial
injury
Muscle rupture = 100%
structural damage.
Complete tearing with or
without muscle retraction
Grade IV
X Complete tear of the
muscle and fascia of the
muscle –tendon unit
X X X

6. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Typical case in professional sports
• high level player
• muscle problems
• cannot start
or must stop training/
competition!
• MRI-negative – (or edema only)

7. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
?
Typical case in professional sports
• high level player
• muscle problems
• cannot start
or must stop training/
competition!
• MRI-negative – (or edema only)
• no structural lesion/tear…
= “functional (=non-structural)
disorder/injury”

8. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Relevance of
“Functional (=non-structural) muscle disorders”
• sub-study “hamstring-injuries”
• in 70% no rupture detectable
(MRI-negative or edema only)
• cause >50% of absence in the clubs!

9. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
International Consensus-Conference
3.3.2011 in Munich
• UEFA, IOC
• Universities: Harvard, Duke, Sydney, Berlin
• Team doctors: FC Chelsea, ManU, Ajax, English National Team

10. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
A. Indirect
Muscle Disorder/
Injury
Indirect Muscle Injuries
Mueller-Wohlfahrt et al., BJSM 2013
Functional
(= non-structural)
Muscle
Disorder
Structural
Muscle
Injury
“Painful muscle disorder without
macroscopic evidence*
of muscle fiber-damage.”
*visible in MRI and/or Ultrasound
“Acute distraction injury of a muscle
with macroscopic evidence*
of muscle fiber-damage.”

11. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Direct Muscle Injury – Contusion
A. Indirect
Muscle Disorder/
Injury
Mueller-Wohlfahrt et al., BJSM 2013
B. Direct
Muscle
Injury
Functional
(= non-structural)
Muscle
Disorder
Structural
Muscle
Injury
Contusion
“Direct (external) muscle trauma,
caused by blunt external force.”

12. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
“Munich-Consensus-Classification”
A. Indirect
Muscle Disorder/
Injury
Type 1:
Overexertion-related
Muscle Disorder
Type 1A:
Fatigue-induced Muscle Disorder
Type 1B:
DOMS
Type 2:
Neuromuscular
Muscle Disorder
Type 2A:
Spine-related Muscle Disorder
Type 2B:
Muscle-related Muscle Disorder
Type 3:
Partial Muscle Tear
Type 3A:
Minor Partial Muscle Tear
Type 3B:
Moderate Partial Muscle Tear
Type 4:
(Sub)Total Tear
Subtotal or Complete Muscle Tear
Tendinous Avulsion
Contusion
Laceration
B. Direct
Muscle
Injury
Functional
Muscle
Disorder
Structural
Muscle
Injury

13. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
MRI structural = t–e aRr ole off urenscotilountiaoln ( with edema)
M. biceps femoris:
edema – hematoma or – structural muscle injury ???

14. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Functional (non-structural) muscle injuries
Type 1:
Overexertion-related
Muscle Disorder
Type 1A:
Fatigue-induced
Muscle Disorder
Aching, increasing
firmness during or after
activity
Type 1B:
DOMS
Inflammative pain
after activity
Type 2:
Neuromuscular
Muscle Disorder
Type 2A:
Spine-related
Muscle Disorder
Band-like firmness along
the muscle
Lumbar genesis!
Type 2B:
Muscle-related
Muscle Disorder
Cramp-like pain, spindle-like
firmness within
muscle belly
Functional
Muscle
Disorder

15. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Type 2a – Case:
Spine-related neuromuscular muscle disorder
25 years old Soccer-player, 1st Bundesliga + National team,
recurrent painful tightness right M. gastrocnemius

16. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Type 2a – Case:
Spine-related neuromuscular muscle disorder
19 years old Soccer-player, 1st Bundesliga,
recurrent painful tightness hamstrings

17. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Type 2b:
Muscle-related neuromuscular disorder
• neuromuscular tonus regulation disorder
• of the reciprocal inhibition,
i.e. the neuromuscular control mechanism
> muscle firmness, cramp-like pain
(Fig.: D. Blottner)
- - - = Muscle-cell
red = Nerve
green = postsynaptic
Membrane

18. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
“Munich-Consensus-Classification”
- Structural Injuries -
Structural
Muscle
Injury
Type 3:
Partial Muscle Tear
Type 3A:
Minor Partial Muscle Tear
Type 3B:
Moderate Partial Muscle Tear
Type 4:
(Sub)Total Tear
Subtotal or
Complete Muscle Tear
Tendinous Avulsion

19. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Injury mechanism - Structural Injuries
• acute longitudinal distraction
• over elastic limits of muscles
• eccentric loading while the muscle is tensed
Abb: D. Böhning, 2002

20. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Type 3: Minor vs. Moderate partial tear
• structural injuries must be
subclassified
• different absence time
• what makes
the difference???

21. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Type 4: Complete muscle tear/
Tendinous avulsion
• complete muscle tears – very rare
• subtotal tears or
• tendinous avulsions – more frequent
• proximal M. rectus femoris
MRI sagittal
• proximal hamstrings
• proximal M. adductor longus
• (distal M. semitendinosus)

22. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Structural muscle injuries
Type 3:
Partial Muscle Tear
Type 3A:
Minor Partial Muscle Tear
“snap”, during activity,
sudden onset, sharp,
needle-like or dull pain
- Symptoms -

23. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Type 3:
Partial Muscle Tear
Type 3A:
Minor Partial Muscle Tear
“snap”, during activity,
sudden onset, sharp,
needle-like or dull pain
Type 3B:
Moderate Partial Muscle Tear
+ possibly followed by fall,
often noticeable tearing
Type 4:
(Sub)Total Tear
Subtotal or
Complete Muscle Tear
Tendinous Avulsion
during activity, sudden
onset, often followed by
fall, impact-like, dull pain

24. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Differentiation - Location

25. Type
Definition
Symptoms
Clinical Signs
Location
Ultrasound/
Dr. med. H.-W. Müller-MR-imaging
Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
1A
Fatigue-induced
Muscle Disorder
Aching tightness. Increasing with continued
activity.
Can occur during activity. Can provoke pain
at rest
Tight muscle band, no edema.
Dull, diffuse, tolerable pain. Athlete reports of
“muscle tightness”
Focal involvement up to entire
length of muscle
Negative for muscle
disruption
1B
Delayed-Onset
Muscle Soreness
(DOMS)
Acute inflammative pain.
Pain at rest.
Hours after activity
Edematous swelling, stiff muscles. Limited range
of motion of adjacent joints.
Pain on isometric contraction. Therapeutic
stretching leads to relief
Mostly entire muscle or muscle
group
Negative for muscle
disruption or edema only
2A
Spine-related
Neuromuscular
Muscle Disorder
Aching tightness. Increasing with continued
activity.
No pain at rest
Band-like increase of muscle tone. Edema
between muscle and fascia.
Occasional skin sensitivity. Defensive reaction on
muscle stretching.
Pressure pain.
Lumbar/iliosacral dysfunction
Muscle bundle or larger muscle
group along entire length of muscle
Negative for muscle
disruption or edema
(between muscle and fascia)
only
2B
Muscle-related
Neuromuscular
Muscle Disorder
Aching, gradually increasing muscle
tightness and tension.
Cramplike pain
Circumscribed (spindle-shaped) area of
increased muscle firmness.
Edematous swelling.
Therapeutic stretching leads to relief.
Pressure pain
Mostly within the muscle belly
Negative for muscle
disruption or edema
(intramuscular) only
3A
Minor Partial
Muscle Tear
Sudden sharp, needle-like or stabbing pain
at time of injury.
Athlete often experiences a “snap” followed
by a sudden onset of localized pain.
Usually cannot continue activity
Well-defined localized pain.
Probably palpable defect in fiber structure within
a hypertonic muscle band.
Pain on passive stretching
Primarily muscle-tendon junction
(intramuscular tendon can be
involved)
Positive for fiber disruption on
high resolution MR-imaging.
Intramuscular hematoma
3B
Moderate Partial
Muscle Tear
Sudden stabbing, sharp or dull pain, often
noticeable tearing at time of injury.
Athlete often experiences a “snap” followed
by a sudden onset of localized pain.
Cannot continue activity
Well-defined localized pain.
Palpable defect in muscle structure, often
obvious hematoma, fascial injury.
Pain on passive stretching.
Loss of muscle function
Primarily muscle-tendon junction
(intramuscular tendon can be
involved)
Positive for significant fiber
disruption, probably including
some retraction. With fascial
injury and intermuscular
hematoma
4
Subtotal/
Complete Muscle Tear/
Tendinous Avulsion
Sudden impact-like, dull pain at time of
injury. Cannot continue activity
Large defect in muscle, obvious hematoma.
Pain on passive stretching.
Loss of muscle function
Tendinous avulsion: palpable gap, obvious
hematoma, muscle retraction, pain with
movement.
Loss of muscle function
Muscle-tendon junction
(intramuscular tendon can be
involved)
or bone-tendon junction
Subtotal/complete
discontinuity of muscle/
tendon. Possible wavy
tendon morphology and
retraction. With fascial injury
and intermuscular hematoma
Con
tusion
Direct muscle injury
Dull pain at time of injury, possibly
increasing due to increasing hematoma
Dull, diffuse pain.
Obvious hematoma possible.
Pain on movement
Any muscle, mostly vastus
intermedius and vastus lateralis
Diffuse or circumscribed
hematoma in varying
dimensions displacing or
compressing muscle fibers.
Muscle fibers possibly torn off
by the impact

26. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Limitations
• since diagnosis based on clinical
examination AND imaging:
clinical experience and high quality
images is needed
• Functional disorders challenging
to diagnose
More studies to determine:
• clear cut off between minor and
moderate partial tear
• relevance of muscle edema?

27. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Validation of the new classification system
Ekstrand et al. 2013, BJSM Epub ahead of print
• UCL-substudy
• 393 thigh (ant.+post.) muscle injuries in 31 European teams
• 100% response rate = proof of practical acceptance
• “positive prognostic validity for return to play”:
• “sub-classification of structural injuries correlates with return to play”
• “functional disorders are often underestimated”

28. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Absence after muscle injury
Type 3:
Structural Partial Muscle Tear
Muscle
Injury
< 7 days
Type 1:
Overexertion-related
Muscle Disorder
Type 2:
Neuromuscular
Muscle Disorder
Functional
Muscle
Disorder
≈ 10-14 days
Type 4:
(Sub)Total Tear
≈ 4-6 weeks
≈ 12 weeks

29. Dr. med. H.-W. Müller-Wohlfahrt
Dr. med. L. Hänsel
PD Dr. med. P. Ueblacker
Thank you!
open access: www.pubmed.org
Validation article: