anatomy pathophysiology diffenets types

1. MYOSITIS OSSIFICANS
Dr.k.prashanth kumar
S V S Medical College Hospital
MAHABUBNAGAR

2. MYOSITIS OSSIFICANS
• Acquired development of non neoplastic heterotopic
ossification within soft tissues
• Most often in response to localized trauma
• Although the process most commonly develops within
skeletal muscle, the term itself is a misnomer, because
nonmuscular tissue may be involved, and inflammation is
rare.
• Adolescents & young adults, predominantly men, are
affected most frequently, although it has been reported in
infancy as well

3. ECTOPIC OSSIFICATION
Ectopic ossification – formation of pathologic bone
• Common term for
– Heterotopic Ossification (HO)
– Myositis Ossificans (MO)
– Periarticular calcification
• HO & MO - deposition of mature lamellar new bone
- share radiologic & histologic features
• HO develops in non osseous tissue while MO forms in damaged or
inflamed muscle
• Periarticular calci. denotes deposition of Cal. Pyrophos. in collateral
lig. & joint capsule - radiologically it does not display trabecular organisation
Anne M Casavant, Hill Hastings II, Indianapolis, Journal of Hand Therapy – 2006; 19:255 -67

4. Difference between normal bone & ectopic bone
Normal bone : has periosteal covering
- outer fibrous layer
- inner vascular cambium layer
Ectopic bone: does not have periosteal covering

5. ETOLIOGY
PRECIPITATING FACTORS
- single or repetitive trauma (70%)
- severe thermal injury
- neurologic conditions - posttraumatic paraplegia
- brain injury
- orthopaedic operations – THR
GENETIC & DEVELOPMENTAL FORMS
- fibrodysplasia ossificans progressiva
- progressive osseous heteroplasia
- pseudomalignant heterotopic ossification
- Albright hereditary osteodystrophy,
- parosteal fasciitis

6. PATHOGENESIS
• Following cellular injury - degeneration and necrosis of the tissue
followed by histiocytic invasion during removal of necrotic debris
• Within 3 or 4 days, fibroblasts from the endomysium invade the
damaged area and primitive mesenchymal cells proliferate within
the injured connective tissue
• The fibroblasts and mesenchymal cells then give rise to osteoid and
chondroid tissue as early as 4 to 5 days after injury.
• As the process of osteoid & mineralisation evolves, it progresses
inward towards the centre.

7. PATHOGENESIS
• The reactive bone is gradually replaced by mature lamellar bone
• This centripetal pattern of ossification and maturation develops
during the second week to second month
• With passage of time mass is well demarcated & decreases in
volume and in some it may completely resolve
• Reduced collagen degradation in polytraumas with traumatic
brain injury causes enhanced osteogenesis
Journal of Neurotrauma
Volume 23, No 5, 2006
Jonas Andermehr, Andreas Elsner, Axel Jubel et al.,

8. HIGH RISK POPULATION
• idiopathic skeletal hyperostosis
• ankylosing spondylitis
• preexisting ipsilateral or contralateral heterotopic
ossification
• hypertrophic osteoarthrosis
• post-traumatic arthritis
• Postoperative
• closed head injury, stroke, and prolonged immobilization

9. Common sites of HO in Elbow
Collateral Lig
Medial
Lateral
Posterior HO
Olecranon Extension
Olecranon Fossa
Humeroulnar bridge
anterior
Humeroradial HO
Radioulnar synostosis

10. CLINICAL FEATURES
• Typically begin approximately 1 to 3 weeks after an injury
• Localized pain and a palpable mass.
• Increased warmth, swelling
• Progressive loss of ROM - hallmark sign
• A low-grade fever
• mildly elevated ESR

11. CLINICAL FEATURES
• Limb involvement
- quadriceps, hip
- brachialis
although virtually any region of the body can be affected
• increase in the firmness of the lesion
• decrease in pain occur over an 8 to 12 wk period
• entrapment of the nerves (ulnar, median, radial)
• development of varying degrees of contracture of the affected part.

12. RADIOGRAPHIC FEATURES
EARLY PLAIN RADIOGRAPHS
- non calcified mass in the soft tissues
Within 2 to 4 weeks after the injury
- floccular calcifications begin to appear within the mass
- if the cambium layer of the periosteum was involved in the
initial injury, a periosteal reaction of the underlying bone
Over a 6 to 8 wk period - serial x rays at 1 to 2 wk intervals -
- peripheral osseous maturation of the lesion, with
- central lucent zone and a lucent line separating it from the
underlying cortex , distinguishing from an extraosseous sarcoma
After 5 to 6 months
- mature bone is evident, and the lesion may show a decrease in
overall size

13. RADIOGRAPHIC FEATURES
• CT scan
- delineats the zonal maturation and cortical
separation when the diagnosis is unclear
• Other imaging modalities
- bone scintigraphy
- ultrasound
- MRI
- leukocyte scanning, and angiography, particularly
in early lesions or in difficult cases
In patients with a typical history of trauma and localized findings with x ray
evidence of progressive peripheral osseous maturation, the use of these
other imaging modalities is infrequently required.

14. HISTOPATHOLOGY
The hallmark is the zonal phenomenon (Ackerman)
• CENTRAL (inner) ZONE - undifferentiated cells and atypical mytotic
figures, which may be impossible to
distinguish from a sarcoma
• AN ADJACENT (middle) ZONE - well-oriented osteoid formation in
a non-neoplastic stroma
• PERIPHERAL (outer) ZONE - well-oriented lamellar bone, clearly
demarcated from the surrounding
tissue
Ackerman LV. Extra-osseous localized non-neoplastic bone and cartilage formation. Journal Bone
Joint Surg Am 1958;40:279.

15. • The origin of the bone-forming cells in myositis ossificans
remains unknown. Recent investigations into the role of
extraskeletal osteogenic precursor cells, and the local
factors that induce them, may provide insights into the
formation of MO
• Origins of ectopic bone formation in myositis ossificans,
and in other disorders characterized by the formation of
heterotopic ossification .
Illes T, Dubousset J, Szendroi M, et al. Characterization of bone-forming cells in post-
traumatic myositis ossificans by lectins. Pathol Res Pract 1992;188:172

16. CLASSIFICATION
• MO secondary to Trauma
- Blunt
- Thermal
- Penetrating
- Iatrogenic
• MO assoc. with neurological disorders
- Traumatic paraplegia
- Traumatic quadriplegia
- Closed Head injury
• Localised MO of unknown origin
• Myositis Ossificans Progressiva

17. CLASSIFICATION OF HO
Class I - no functional ROM limitation
CLASS II - limitation of functionl ROM
subdivided into 3 categories - which plane
flexion/extension pronation/supination
CLASS III - ankylosis of elbow - limiting flexion/extension
pronation/supination
subdivided in which plane it is ankylosed
Hastings H, Graham TJ, Classification and Treatment of HO about elbow and forearm.
Hand clinic. 1994;10:417-37

18. CLASSIFICATION
(size of the mass)
Ilahi, Omer A, MD; Strausser, David W, MD; Gabel, Gerard T, MD
Department of Orthopedic Surgery, Baylor College of Medicine, Houston, Tex
Angle subtended by the largest area of the ectopic fragment on
lateral radiograph measuring from the centre of rotation
GRADE I
< 30
GRADE II
30 - 60
GRADE III
> 60
GRADE IV
Ulnohumeral
ankylosis on any x ray
view

20. MYOSITIS OSSIFICANS PROGRESSIVA
(Fibrodysplasia ossificans progressiva)
“stone man syndrome”
• Autosomal dominant connective
tissue disorder
• muscle tissue and connective tissue
–tendons & lig.gradually replaced
by bone (ossified), extra-skeletal or
heterotopic bone that constrains
movement
• Malformed big toes - single phalanx
• No cure
• Usually die early - malnutrition &
recurrent infections

21. MANAGEMENT
• PHYSICAL THERAPY
• SURGICAL MANAGEMENT

22. MANAGEMENT
Prevention of heterotopic ossification at the site of initial injury would be ideal.
Variable depending on the stage of development
NSAIDs - diminish symptomatology in the early stages.
• Hughston et al. - strict rest of the affected part
- splinting, would allow for more complete
resorption of hematoma and discourage
formation of heterotopic bone
• Thorndike - advocated a combination of rest, icing, compression bandaging,
and avoidance of massage therapy
• Ryan et al. - advocated that the position of splinting of the affected muscle
should be in tension (e.g., flexion for quadriceps contusion)
However, there is presently no clear evidence that such measures prevent the
development of myositis ossificans, or modify its severity.

23. • Single low-dose radiation therapy,
• Indomethacin, aspirins
• Low Energy Extracorporeal Shockwave Therapy for the
Treatment of Myositis Ossificans in a Case of Cerebro
Vascular Accident
• Early passive mobilization are the preventive treatment
modalities suggested by various studies
Bibhuti Sarkar1 , S S Rau2 1 Physiotherapist, 2 Asst. Professor (Physiotherapy), National Institute for the
Orthopaedically Handicapped (N.I.O.H), B. T. Road, Bonhooghly, Kolkata
Indian Journal of Physiotherapy & Occupational Therapy. April-June 2013, Vol. 7, No. 2

24. THERAPY PROGRAMME
(after injury / surgery)
• Acute & oedematous phase (first 2 wks)
• Inflammatory phase (2 - 6 wks)
• Fibrotic phase (6 - 12 wks)
• Late phase (3 - 6 months)

25. THERAPY PROGRAMME
(after injury / surgery)
• Acute & oedematous phase (first 2 wks)
- oedema controlling measures - inflamm.
- ice, compressive dressings, pain management
- active ROM within the parameters &
stability (otherwise muscles quickly lose strength)
• Inflammatory phase (2 - 6 wks)
- prolific unorganised scar tissue present(very active but
malleable and deformable) & responds to therapy
- self passive stretching & serial static /dynamic splinting
4 – 6 times a day for 30 mts
- when HO is revealed on x ray - at 4 to 6wks, therapy
contd. to maximise ROM -

26. THERAPY PROGRAMME
(after injury / surgery)
• Fibrotic phase (6 - 12 wks)
- scar tissur fully formed but is reorganising & responds
to motion & stress
- fractures if any would have healed by this time
- guarded increase in the intensity of exercise
- day splinting in the position of max stretching
- resistive exercises in the splint will maximise ROM gains
• Late phase (3 - 6 months)
- scarring is organised (fibrous tissue)
- splinting to recapture ROM contd. as long as gains
- splinting is weaned off & home strengthening prog . to
regain muscle strength

27. INDICATIONS FOR SURGICAL INTERVENTION:
• Mere presence of HO or limitation of elbow motion
does not warrant surgical excision
• Indicated only when the limited elbow ROM prevents
functional use of the affected extremity
• Performed only when the HO matures after 6 – 12
months

31. Neglected posterior dislocation of
elbow with HO

32. 2 wks after Total Elbow
Arthroplasty for post traumatic
stiff elbow
Anterior HO 6 months after
surgery has not progressed
from the initial size

34. Inverted “V” Osteotomy Excision Arthroplasty for Bony Ankylosis Elbow
28 yr old lady with MO & bony ankylosis
80 months P O follow up
,Coimbatore

35. CONCLUSION
• It is a complex process
• Extent of formation directly related to severity
of injury
• Neural axis injuries & thermal injuries are
predisposing conditions
• Why certain cells differentiate into bone and
not scar remains unclear
• Formation HO begins in the first 2 wks of
injury

36. CONCLUSION
• Ossification progresses over next several
months
• HO matures over period of 6 – 12 months
• Mild degree cases resolve spontaneously
• Comprehensive physical therapy prog. may
restore useful ROM
• Surgery is indicated only when useful ROM
could not be achieved by therapy

37. THANK YOU