Bruce Hamilton Sports medicine physician, High Performance Center, Oakland, New Zeeland, - Classification and Grading of Muscle Injuries: A Review of the Literature (6th MuscleTech Network Workshop) 14th October, Barcelona

1. Classification and Grading of Muscle Injuries An Historical Perspective
Dr Bruce Hamilton
Chief Medical Officer
High Performance Sport NZ / NZ Olympic Committee

3. Mueller-Wohlfahrt et al. 2012
Is this it?

4. Mueller-Wohlfahrt et al. 2012
Is this it?
Where did these come from?

5. 1920’s
1980’s
2000-

6. A retrospective, citation based search for literature which evaluated or utilised a novel muscle classification or grading system (predominantly English Language)
Peer reviewed journal publications
Popular sports medicine textbook sources (prior to 1970)
No systematic search strategy was used
Classification and Grading of Muscle Injuries: A Narrative Review
Hamilton B, Valle X, Rodas G, Til L, Pruna Grive R, Rincon J, Tol J. Submitted BJSM

7. Terminology

8. Terminology “to Classify” and “to Grade”

9. To “Classify”
…describe or categorise the nature of an injury
(for example by its location, mechanism of causation or underlying pathology)

10. To “Grade”
…provide a degree of the injury severity

11. Pathology
Imaging
Clinical RTP
To “Grade”
…provide a degree of the injury severity

12. To “Grade”
…provide a degree of the injury severity
Pathology
Imaging
Clinical RTP

13. Some (incomplete) history…

14. 1900
1970
1902
Crowley, D D
Suturing of Muscles and Tendons. California State Journal of Medicine. April 1902
1931
Heald, C B
Injuries and Sport. Oxford Medical Publications. London 1931 P 359 - 362
1933
Smart, M.
The Principles of Treatment of Muscles and Joints by Graduated Muscular Contractions. Oxford Medical Publications. London 1933 P67 - 72
1938
Thorndike, A.
Athletic Injuries: Prevention, Diagnosis and Treatment. Augustus Thorndike (Jnr). Lea and Febiger 1938
1957
Featherstone, D F.
Sports Injuries. 1957 John Wright and Sons Ltd. Bristol P126-139
1960
Colsen J.
Strapping and Bandaging for Football Injuries. Chapter IV: Injuries of the thigh muscles. P13-30. First published 1953; reprint 1960. The Football Association. London
1962
Page, E.
Athletic Injuries and Their Treatment. Arco Publications London 1962 P 20-34
1962
Williams, J G P.
Sports Medicine. 1962. The Williams and Wilkins Company. Baltimore. P 79 - 97
1962
O'Donoghue, D.
Treatment of Injuries to Athletes 1962 W B Saunders Co Philadelphia (Reprint October 1962) P 41-58
1964
Tucker, W E. & Armstrong J R.
Injury in Sport: The Physiology, Prevention and Treatment of Injuries associated with Sport. 1964 London Charles Birchall and Sons Ltd. P 320-326
1966
Rachun, A.
Standard Nomenclature of Athletic Injuries. American Medical Association. 1966 Chicago.
Classification based on Force application and anatomical location of injured tissue
1. Internal (Secondary to violent exertion):
Rupture where fibres meet the tendon
Rupture of body of Muscle
Rupture of Tendon
2. External (Secondary to Direct violence):
Grading based on clinical appearance
Slight
Loss of tone. Lengthening of muscle, not capable of normal contraction. Microscopically some of muscle fibres may be torn. Connective tissue may be injured. Haemorrhage and Oedema. Clinically, pain with stretch.
Severe
Greater loss of Contractility and tonicity, Lymph and blood accumulation with adhesion formation.
Classification based on source of force application
Grading based on pathological findings (presumed theoretical)
1. Internal force
Slight
No macroscopic damage. Microscopic may exist. Connective tissue may be damaged, with haemorrhage and oedema
2. External force
Severe
Rupture of multiple or individual fibres. Supporting CT framework damaged. Myo-fascial sheath ruptured. Acute pain
Grading based on clinical appearance and theoretical pathology
Pull / Tear / Strain
A few muscle fibres and the supporting connective tissues involved. Damage to both contractile and non-contractile elements. Haematoma - the degree of haemorrhage and haematoma formation is directly proportional to the vascularity of the muscle and inversely to the degree of general muscle tone
Complete Rupture
Anatomical discontinuity and palpable gap.

15. 1900
1970
1966
Rachun, A.
Standard Nomenclature of Athletic Injuries. American Medical Association. 1966 Chicago.
Grading based on clinical appearance and theoretical pathology
First Degree Strain (AKA: Mild Strain; slightly pulled muscle)
Trauma to musculo-tendinous unit due to excessive force or stretch. Localised pain, aggravated by movement; Minor disability; Mild swelling, ecchymosis, local tenderness; minor disability. Tendency to recurr. Minimal haemorrhage, inflammation mainly, some disruption of musculo-tendinous tissue.
Second Degree Strain (AKA: Moderate Strain; Moderately pulled muscle)
Trauma to musculo-tendionous unit due to violent contraction or excessive forced stretch. Localised pain, aggravated by movement; Moderate disability; Moderate swelling, ecchymosis, local tenderness and disability. Stretching and tearing of fibres, without complete disruption; tendency to reccurrence, aggravation.
Third Degree Strain (AKA: Severe Strain; Severely pulled muscle)
Trauma to musculo-tendionous unit due to violent contraction or excessive forced stretch. Severe pain, and disability; Severe swelling, ecchymosis, haematoma, palpable defect and loss of muscle function. Muscle or tendon rupture, including musculotendon junction or avulsion with bone.

16. 1970
Classification and grading well established
“Categorical”

17. Muscle Injury: Categorical Grading
Grade I Grade II Grade III
Injury

18. Classification and grading well established
“Categorical”
No evidence of correlation with:
Underlying Pathology
or
Return to Play

19. 1970
1999

20. 1970
1999
Grade 0
Sonographically Normal.
Grade I
Specific hypoechoic area, <15 mm in longest axis; <5% of muscle involved.
Grade II
5-50% muscle involvement. Partial Muscle Rupture. Sudden "snap" with intense localised pain. Clearly demonstrated hypo or an-echoic gap, with "bell clapper" sign. Most lesions start at the perimysium boundary of the muscle. Typically 5- 6 weeks healing time.
Grade III
Full thickness tear of muscle or fascia, with extravasation of collection away from injured part of muscle. Associated with severe pain.
1977
Wise D.
Physiotherapeutic treatment of athletic injuries to the muscle-tendon complex of the leg. Journal of the Canadian Medical Association. September 17, 117, 1977 P635-639
1985
Renstrom, P.
Muscle Injuries in Sports. In: Sports Medicine in Track and Field Athletics. Edited by: Ljungqvist A, Peltokallio P, Tikkanen H. IAAF/ Finnish AAA. 1985 P17-28
1989
Safran M, Seaber A, Garrett W.
Warm-Up and Muscular Injury Prevention: An Update. Sports Medicine 8 (4) 239-249
1993
Peetrons, P. & Creteur V.
Peetrons P & Creteur V. 1993 In:Imagerie Des Parties Molles De L’Appareil Locomoteur Editors: Chevrot A, Kahn M, Morvan G. Sauramps Medical P229 - 235; Also see: Peetrons P. European Radiology 2002 12:35–43

21. 1970
1999
1977
Wise D.
Physiotherapeutic treatment of athletic injuries to the muscle-tendon complex of the leg. Journal of the Canadian Medical Association. September 17, 117, 1977 P635-639
1985
Renstrom, P.
Muscle Injuries in Sports. In: Sports Medicine in Track and Field Athletics. Edited by: Ljungqvist A, Peltokallio P, Tikkanen H. IAAF/ Finnish AAA. 1985 P17-28
1989
Safran M, Seaber A, Garrett W.
Warm-Up and Muscular Injury Prevention: An Update. Sports Medicine 8 (4) 239-249
1993
Peetrons, P. & Creteur V.
Peetrons P & Creteur V. 1993 In:Imagerie Des Parties Molles De L’Appareil Locomoteur Editors: Chevrot A, Kahn M, Morvan G. Sauramps Medical P229 - 235; Also see: Peetrons P. European Radiology 2002 12:35–43
1993
Pomeranz SJ, Heidt RS Jr.
MR imaging in the prognostication of hamstring injury. Work in progress. Radiology. 1993 Dec; 189(3): 897-900
Classification based on MRI Findings
Grading based on MRI Findings
14 muscle injuries only
Anatomical Location (Tendon / Myotendinous / Superficial /
Extent of Muscle Involvement
Less than or Greater than 50% muscle involvement
Tendon involvement associated with worse prognosis
Presence of Oedema, Haemorrhage, Fluid Collection
Greater muscle involvement, worse prognosis

22. 1970
1999
1977
Wise D.
Physiotherapeutic treatment of athletic injuries to the muscle-tendon complex of the leg. Journal of the Canadian Medical Association. September 17, 117, 1977 P635-639
1985
Renstrom, P.
Muscle Injuries in Sports. In: Sports Medicine in Track and Field Athletics. Edited by: Ljungqvist A, Peltokallio P, Tikkanen H. IAAF/ Finnish AAA. 1985 P17-28
1989
Safran M, Seaber A, Garrett W.
Warm-Up and Muscular Injury Prevention: An Update. Sports Medicine 8 (4) 239-249
1993
Peetrons, P. & Creteur V.
Peetrons P & Creteur V. 1993 In:Imagerie Des Parties Molles De L’Appareil Locomoteur Editors: Chevrot A, Kahn M, Morvan G. Sauramps Medical P229 - 235; Also see: Peetrons P. European Radiology 2002 12:35–43
1993
Pomeranz SJ, Heidt RS Jr.
MR imaging in the prognostication of hamstring injury. Work in progress. Radiology. 1993 Dec; 189(3): 897-900
1999
Connell D, Potter H, Sherman M, Wickiewicz.
Injuries of the Pectoralis Major Muscle: Evaluation with MR Imaging. Connell D, Potter H, Sherman M, Wickiewicz. Radiology 1999 210 785-791
2000
Jarvinen T, Kaariainen M, Jarvinen M, & Kalimo H.
Muscle Strain Injuries. Current Opinion in Rheumatology 2000 12 155-161

23. 1970
1999
2000
Consolidation of Classification and Grading Systems
Descriptive Imaging Studies
No evidence of correlation with:
Underlying Pathology
or
Return to Play

24. Evidence base for clinical and radiological categorical grading
Continuous variables for grading
Combinations of radiological and clinical evaluations
2000 -
Evidence base for categorical grading (clinical & radiological)

25. Evidence base for clinical and radiological categorical grading
Continuous variables grading
Combinations of radiological and clinical evaluations
2000 -
Evidence base for categorical grading (clinical & radiological)
Continuous variables for grading

26. Evidence base for clinical and radiological categorical grading
Continuous variables grading
Combinations of radiological and clinical evaluations
2000 -
Evidence base for categorical grading (clinical & radiological)
Continuous variables for grading
“Novel” classification and grading systems
(combinations of radiological and clinical)

28. Evidence base for clinical and radiological categorical grading
Continuous variables grading
Combinations of radiological and clinical evaluations
2000 -
Evidence base for categorical grading (clinical & radiological)
Continuous variables for grading
“Novel” classification and grading systems
(combinations of radiological and clinical)

29. Sports Medicine 2014

30. BIAS

31. LEVEL OF EVIDENCE

32. Moderate Evidence:
MRI Negative injuries associated with shorter RTP
Limited Evidence:
Central tendon disruption, injury not affecting the musculotendinous junction and a total rupture with a longer time to RTP
No Association or Conflicting Evidence:
All other variables
Woodley 2013
Aspetar Sports Medicine Journal

34. 2014
Limited (but developing) evidence for imaging correlation with return to play
Limited (but developing) evidence for clinical correlation with return to play
No direct evidence for underlying pathology and prognosis
Complex application of limited data into “classification and grading” systems

35. Conclusion
By 1966 classification and grading of muscle injury was well established
Remains limited evidence to support the predictive merits of either categorical or continuous grading of muscle injury
Categorical grading will likely over- simplify the biological reality

36. Thank You

37. •Limited financial interest*
•Relatively few subjects
•Complicated research
•“Natural History”