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Legg Calve Perthes Disease

Synonyms– Perthes Disease

– Osteochondritis Deformans Juvenilis

– Childhood Aseptic Necrosis of Femoral Head

Dr. P. Ratan khuman (PT)M.P.T., (Ortho & Sports)

Definition¨ Perthes’ disease is a self-limiting form

of osteochondrosis of the capital femoral epiphysis of unknown aetiology that develops in children commonly between the ages of 5 – 12 years.

¨ It is a condition of immature hip caused by necrosis of the femoral epiphysis; the femoral head subsequently deforms as necrotic bone is replaced by living bone.

¨ It is Hip disease occurring during early childhood and caused by impaired circulation in the femoral head.

April 11, 2023 Dr.Ratan M.P.T.,(Ortho & Sports) 2

Historical background¨ The disease was described almost

simultaneously, in 1910, by –– G. C. Perthes in Germany, – J. Calve in France – A.T. Legg in America. – Hence name – “Legg Calve Perthes

Disease” ¨ The newly discovered x-ray technique

allowed doctors to differentiate it from inflammatory forms of hip disease.


Etiological Factors that play a role in

development of illness¨ Vascular supply¨ Increased intra-articular pressure¨ Intraosseous pressure¨ Coagulation disorder¨ Growth hormones¨ Growth¨ Social conditions¨ Genetic factors


¨ Vascular supply: – Angiograms & laser Doppler flow

measurements • Medial circumflex artery is missing or

obliterated in many cases • Obturator artery or the lateral

epiphyseal artery are also affected in some cases.


¨ Increased intra-articular pressure: – Animal experiments have shown that

an ischemia similar to that in Perthes disease can be generated by increasing the intra-articular pressure.

– However, the condition of transient synovitis of the hip does not appear to be a precursor stage of Perthes disease as the increased pressure resulting from the effusion in transient synovitis does not lead to vessel closure.


¨ Intraosseous pressure: – The measurement of intraosseous

pressure in Perthes patients has shown that the venous drainage in the femoral head is impaired, causing an increase in intraosseous pressure.

– In animal studies, the intraosseous injection of fluid, and the associated increase in pressure, produced a condition similar to Perthes disease


¨ Coagulation disorder : – Study have found a coagulation

disorder in 75% children with Perthes disease.

– In most cases the disorder was thrombophilia.

– Rarely the disorder involved elevated serum levels of lipoprotein, a thrombogenic substance.

– Recent studies have questioned the significance of clotting factors as an etiological component


¨ Growth hormones : – While earlier studies found reduced

levels of the growth hormone.– Recent studies have not shown any

difference from control groups in respect of hormone status


¨ Growth: – Children with Perthes disease are

shorter, on average, than their peers of the same age & show a retarded skeletal age (cartilaginous dysplasia).

– The maturation disorder occurs between the ages of 3 and 5 years.

– Both the trunk and extremities lag behind in terms of growth.


¨ Growth cont…– The shortening of the extremities is

also accompanied by small feet.– Since this shortening is offset by

excessive growth at a later age, patients who suffered from Perthes disease as children are no shorter, as adults, than the population average.

– More recent experimental studies have shown that the metaphyseal changes are based on a growth disorder.April 11, 2023 Dr.Ratan M.P.T.,(Ortho & Sports) 11

¨ Social conditions: – Studies in the UK have shown that

Perthes disease is more common in the lower social status.

– The authors suggest a poorer diet during pregnancy as one possible explanation for this phenomenon.

– A recent study did not confirm this theory


¨ Genetic factors: – Studies have shown that first degree

relatives of children with Perthes disease are 35 times more likely to suffer from the condition than the normal population.

– Even second- and third-degree relatives show a fourfold increased risk.


¨ To sum up –– Genetic factors play an important

role in the etiology of Perthes disease.

– The illness develops as a result of impaired circulation in the medial circumflex artery in association with a skeletal maturation disorder with delayed growth in children aged from 3–5 years.


Occurrence

¨ In white population is 10.8 per 1,00,000 children & adolescents aged from 0–15 year

¨ In Asians is 3.8 per 1,00,000 ¨ In Mixed-race populations is 1.7

per 1,00,000¨ In Blacks is 0.45 per 1,00,000¨ The highest reported incidence

was in city of Liverpool (UK) early 1980’s, with 15.6 per 1,00,000 individuals under 15 years of age.


¨ A decline was subsequently observed in the 1990’s – possibly as a result of the improved social conditions.

¨ Similarly high incidence 15.4 per 1,00,000 was recently reported in a rural area of Southwest Scotland.

¨ In Sweden an annual incidence of 8.6 per 100,000 people under 15 yrs was Determined.


Epidemiology

¨ Disorder of hip in young children¨ Usually ages 4-8yr¨ As early as 2yr, as late as teenager ¨ Boys: Girls – 4/5:1¨ Bilateral – 10-12%¨ No evidence of inheritance


Classification

¨ All known classifications of Legg-Calvé-Perthes disease are based on the morphological findings on x-rays.


Morphological classifications of the extent of the lesion¨ Classification according to

Catterall (Common)¨ Classification according to Salter &

Thompson¨ Classification according to Herring



Classification of extent of lesion - (Acc to Catterall)

Grade Characteristics

I Only anterolateral quadrant affected

II Anterior third or half of the femoral head

III

Up to 3/4 of the femoral head affected, only the most dorsal section is intact

IV Whole femoral head affected

Grade – I

¨ Only anterolateral quadrant affected


Grade - II

¨ Anterior third or half of the femoral head


Grade – III

¨ Up to 3/4 of the femoral head affected,

¨ only the most dorsal section is intact


Grade – IV

¨ Whole femoral head affected


Classification according to Salter & Thompson

Group

Characteristics

ASubchondral # involving <50% of the femoral dome

BSubchondral # involving >50% of the femoral dome


¨ 8-year old boy with subchondral fracture and incipient Legg-Calve- Perthes disease


Classification according to HerringGroup

Characteristics

A Lateral pillar not affected

B >50% of height of lateral pillar preserved

C <50% of height of lateral pillar preserved


Classification according to Herring

“A”Lateral pillar not

affected



“B”>50% of height of

lateral pillar preserved



“C”<50% of height of

lateral pillar preserved


Deformation of the femoral head¨ Children femoral head becomes

deformed during revascularization of the epiphysis.

¨ There is evidence to suggest that irreversible deformation occurs either in the latter part of the stage of fragmentation or very early in the stage of regeneration.


¨ Enlargement of the femoral head –– The femoral head becomes enlarged

as the disease progresses. – The extent of enlargement is

proportional to the degree of its deformation.


¨ Capital physeal growth impairment –– The avascularity of the epiphysis

impairs normal growth at the capital femoral physis and, as a result of this, in some older children the femoral neck is foreshortened.

– The trochanter continues to grow normally and as a consequence the GT outgrows the femoral head and neck.

– This results in altered mechanics of the hip and a Trendelenburg gait.


¨ Secondary degenerative arthritis of the hip –– All 3 morphological changes in the

proximal femur listed above can contribute independently or collectively to the development of secondary degenerative arthritis.

– However, the most important factor that predisposes to the development of degenerative arthritis is deformation of the shape of the femoral head.April 11, 2023 Dr.Ratan M.P.T.,(Ortho & Sports) 34

Stages of Perthe’s Disease (Waldenström Staging)

1. Avascular stage2. Fragmentation stage3. Re-ossification stage4. Healed stage


Stage and Characteristics

¨ Avascular stage. – The femoral head

appears slightly flattened & denser than normal on the x-ray.

– The joint space is widened (Waldenström sign).

– Lateralisation of the femoral head.


Stage and Characteristics cont…¨ Stage of resorption

(Fragmentation)- Femoral head breaks

up into fragments- Lucent areas appear in

the femoral head- Increased density

resolves- Acetabular contour is

more irregular


Stage and Characteristics cont…¨ Stage of Re-

ossification– The femoral head is

rebuilt– New bone formation

occurs in the femoral head


Stage and Characteristics cont…¨ Healing stage

– End stage with or without defect healing (normal hip, coxa magna, flattened head etc.)


CLINICAL FEATURES

¨ EARLY (Necrosis, Fragmentation) –– Synovitis – There is pain & limp of insidious

onset.– Pain usually in groin, radiating to

thigh or knee.– Limp is typically antalgic gait.

¨ LATE (Re-ossification – Remodeling) –– There is limp (antalgic, short-leg or

stiff hip).– Pain is mild and usually in the hip

area.


Stages of radiological changes in Perthe's

disease:¨ Early Stage –– Joint space widening (waldenstrom's sign)– Increased density of femoral epiphysis– Subchondral fracture, or “crescent sign,”

seen on lateral radiograph¨ Mid Stage –

– Fragmentation and flattening of head (Coxa magna)

– Widening of the physis (waldenstrom's sign)

– Femoral neck cysts– Extrusion of the femoral head


Stages of radiological changes in Perthe's

disease: cont…¨ Late Stage– Coxa magna High-riding trochanter Flattened femoral head Irregular articular surface


Physical Therapy Assessment &

Diagnosis


Clinical Assessment¨ A thorough history and examination be

completed to establish an impairment based physical therapy diagnosis and individualized plan of care (APTA).

¨ It is recommended initial evaluation, on a monthly basis or sooner if the pt demonstrates a change in status, and at discharge: – Pain and symptoms – Lower extremity PROM & AROM – Lower extremity strength – Gait – Balance – Outcome measures


Pain and symptoms

¨ It is recommended to assessed using –– Oucher pain scale– Numerical Rating Scale (NRS)


Lower Limb PROM & AROM¨ Fluid filled or linear goniometer is

recommended to measure ROM. ¨ Hip motions to assess include –

– Hip flexion, abduction, extension, internal rotation, external rotation.

¨ The knee & ankle ROM be assessed at the initial evaluation and thereafter if they are significantly limited.


Lower Extremity Strength

¨ Quantitative muscle testing is recommended using a hand held dynamometer due to its high intra- & inter-rater reliability.

¨ MMT also can be used but less reliable.

¨ Muscle groups to assess include –– Hip – Flexors, Abductors, Extensors,

Internal Rotators, External Rotators– Knee – Extensors, Flexors, – Any Other Muscle Group that is

Significantly Limited


Gait

¨ Qualitatively gait assessment is recommended for common LCP deviations. – Note 1: Based on limited

accessibility and feasibility, the gold standard for gait analysis of 3-D gait kinematics and kinetics is not recommended to be used in the clinic.

– Note 2: There is insufficient evidence & lack of reliability & validity to support use of observational gait assessment tools with this population.


Gait cont…

¨ Commonly observed gait characteristics in LCP include, but are not limited to: – Increased hip adduction on stance

leg– Trunk lean outside the normal range– Trendelenburg (hip drop on

unaffected limb while in swing)– Compensated trendelenburg/reverse

trendelenburg/duchenne (trunk lean to the affected side while in stance on the affected limb)

– Toe in or toe out


Balance

¨ Balance be assessed on weight bearing status.

¨ The desired outcome is that the patient maintain balance for age appropriate times for safe ambulation and stair negotiation. – Note: In pts 7 y or older, balance is

to be assessed using the Pediatric Balance Scale.

– If the pt is younger than 7 y old, the test is unavailableApril 11, 2023 Dr.Ratan M.P.T.,(Ortho & Sports) 50

Outcome measure scores

¨ The age appropriate Pediatric Quality of Life Inventory Version 4.0 is recommended.

¨ Physical Functioning section is administered at the initial evaluation, on a monthly basis for reassessment of patient’s reported functional status, and at discharge.


Imaging – Radiographic Feature¨ Widening of the joint space and minor

subluxation¨ Sclerosis¨ Fragmentation and focal resorption¨ Loss of height¨ Metaphyseal cyst formation¨ Widening of the femoral neck & head

(Coxa Magna)¨ Lateral uncovering of the femoral head¨ Sagging rope sign¨ Acetabular remodelling


Frog-lateral View Of The Hips


Caffey’s sign¨ As the disease

progresses, a subchondral # may occur in the anterolateral aspect of the femoral capital epiphysis.

¨ Is an early radiographic feature best seen on the frog-lateral projection.

¨ This produces a crescentic radiolucency known as the crescent, Salter’s or Caffey’s sign


Fragmentation of the femoral capital epiphysis


Sclerosis of epiphysis & widening of joint space in the early stages


Metaphyseal cyst formation within the

femoral neck


‘Sagging Rope Sign’

¨ This a curvilinear sclerotic line running horizontally across the femoral neck.

¨ It is confirmed by 3D CT studies.

¨ It is a finding in AP radiograph in a mature hip with Perthes’ disease.


Ultrasound features

¨ Effusion, especially if persistent¨ Synovial thickening¨ Cartilaginous thickening¨ Atrophy of the ipsilateral quadriceps

muscle¨ Flattening, fragmentation,

irregularity of the femoral head¨ New bone formation¨ Revascularisation with contrast

enhanced power DopplerApril 11, 2023 Dr.Ratan M.P.T.,(Ortho & Sports) 59

Differential Diagnosis

¨ It is important to rule out infectious etiology (septic arthritis, toxic synovitis)

¨ Others:– Chondrolysis -Neoplasm– JRA -Sickle Cell– Osteomyelitis -Traumatic AVN– Lymphoma -Medication


Differential Diagnosis ¨ D/D unilateral

Perthes’ disease:– Transient

synovitis– Septic arthritis– Sickle cell disease

¨ D/D bilateral Perthes’ disease:– Hypothyroidism– Multiple

epiphyseal dysplasia

– Sickle cell disease


Diagnosis

¨ Children with Perthes disease limp and complain of mild to moderate hip pain.

¨ This situation can persist for several weeks.

¨ Clinical examination usually reveals a slight stiff, protective limp.

¨ The ROM of the affected hip is usually restricted, in particular with reduced abduction and internal rotation.


Classification of Phases of Rehab¨ It is recommended that the Classification

Instrument in Perthes (CLIPer) be used to place the patient into a rehabilitation classification phase upon examination.

¨ The patient should be re-examined using the CLIPer on a monthly basis to determine the appropriate progression through the rehab classification stages

¨ It is recommended the patient is referred back to the orthopaedic surgeon if the patient’s status worsens over two consecutive PT sessions



Classification Instrument in Perthes (CLIPer)

Domains

DescriptionScor

e

Pain with ADL

7 to10/10 44 to 6/10 20 to 3/10 0

Hip ROM

Less than 50% of uninvolved side for the majority of directions

6

50 to 75% of uninvolved side for the majority of directions

3

76 to 100% of uninvolved side for the majority of directions

0

Hip Strength

Less than 50% of uninvolved side for the majority of muscle groups

6

50 to 75% of uninvolved side for the majority of muscle groups

3

76 to 100% of uninvolved side for the majority of muscle groups

0

Balance

Pediatric balance score less than 50% of best score (best score=56) OR SLS with eyes open less than 50% of time on uninvolved side

4

Pediatric balance score 50 to 75% of best score (best score=56) OR SLS with EO of uninvolved side 50 to 75% length of time

2

Pediatric balance score 76 to 100% of best score (best score=56) OR SLS with EO 76 to 100% of uninvolved side

0

Gait

NWB and uses an assistive device and without AD, displays excessive gait deficits with decreased efficiency

4

No assistive device & displays excessive deficits without a decrease in efficiency. Uses step to pattern on stairs

2

Non-painful limp Able to perform reciprocal pattern on stairs

0

Total:

Rehabilitation Classification Phase¨ Score total 14 to 24: Severe

Involvement¨ Score total 6 to 13: Moderate

Involvement¨ Score total 0 to 5: Mild

Involvement


Instructions for use

¨ Upon examination, assess pain with ADL’s, hip range of motion, hip strength, balance, and gait.

¨ Assign a correlating score for each domain of assessment based on examination results and total the sum.

¨ Place the patient in a rehabilitation classification phase based on the total score to guide physical therapy treatment.


Physical Therapy Management¨ Supervised PT with a customized

written home ex program in all phases of rehab.

¨ It is recommended that the PT engage in ongoing communication with the patient, family, and referring physician regarding the disease process & plan of care.

¨ It is recommended to progress through the phases of rehabilitation follow a goal based rather than a time based progression.


Phases of Rehabilitation ¨ Severe Involvement Phase (CLIPer

score 14 to 24) ¨ Moderate Involvement Phase (CLIPer

score 6 to 13) ¨ Mild Involvement Phase (CLIPer score

0 to 5)



Goals for Management CLIPer score 14

to 24 CLIPer score 6 to 13

CLIPer score 0

to 5 • Reduce pain to <

7/10 • Increase ROM to

>50% of the uninvolved side • Increase strength

to >50% of the uninvolved side • Patient to be

independent with the appropriate assistive device and weight bearing precautions • Improve balance

to >50% of the maximum Pediatric Balance Scale score or single limb stance of the uninvolved side.

• Reduce pain to < 4/10 • Increase ROM to > 75%

of the uninvolved side • Increase strength to >

75% of the uninvolved side • Progress from use of an

assistive device if approved by physician and without adverse effects • Independence with a

step to pattern on stairs without UE support • Improved efficiency in

walking • Improved balance to >

75% of the maximum Pediatric Balance Scale score or single limb stance of the uninvolved side

• Reduce pain to 1/10 or less • Increase ROM to

>90% of the uninvolved side • Increase strength

to > 90% of the uninvolved side • Improve balance

to >90% of the maximum Pediatric Balance Scale score or single limb stance of the uninvolved side • Ambulation with a

non-painful limp with normal efficiency

Pain Management

CLIPer score

14 to 24

•Hot pack with stretching • Cryotherapy •Medications as prescribed by the referring physician for pain

CLIPer score

6 to 13


CLIPer score 0 to 5




ROM Management

CLIPer score 14 to 24

• Static stretch for LE musculature with or without hot pack•Dynamic ROM & AAROM if muscle guarding due to pain and is unable to achieve end ROM with static stretch. • Perform AROM and AAROM following passive stretching to maintain newly gained ROM . • Stretching for hip – IR, ER, Abd, Extensor, & any other lower extremity motion that is significantly limited

CLIPer score 6 to 13

• Same as above •Dosage of may differ based on patient preference & comfort.

CLIPer score 0 to 5

• Same as above •Dosage of may differ based on patient preference & comfort.

ROM cont…

¨ Static Stretching Parameters –– 2 minutes of stretching/day/muscle

group– 30 second hold time– 4 repetitions per muscle group– If not tolerated, may do 10 to 30

second hold time with repetitions adjusted to meet 2 minute requirement • e.g. if holding 15 seconds, would do 8

stretchesApril 11, 2023 Dr.Ratan M.P.T.,(Ortho & Sports) 72

ROM cont…

¨ Dynamic Stretch Parameters –– 5 second hold– 24 repetitions per muscle group per

day to meet 2 minute stretching time required

¨ Done if patient does not tolerate static stretch


Strengthening Ex (CLIPer score 14 to 24)

¨ Isometric Ex -> Isotonic Ex in gravity lessened -> Isotonic Ex against gravity.

¨ It is appropriate to include concentric and eccentric contractions.

¨ Begin with 2 sets of 10 to 15 rep of each ex, progression to 3 sets of each exs. – Note: If the patient is unable to

perform 2 sets of 10 rep, the difficulty of the ex is to be decreased either through weight or type of ex.



¨ Focus on strengthening of HIP (Abd + Flexors + ER + IR + Extensors + or any other LE muscle group that displays significant strength deficits).

¨ Special attention to gluteus medius to min intra-articular pain & for pelvic control during single leg activities and ambulation .

¨ Weight bearing Vs Non-weight bearing ex is based on patient’s tolerance to weight bearing positions, and safety.



¨ Closed chain double limb exercises with light resistance (less than full body weight)

¨ It is not recommended to perform single limb closed chain ex on the involved side due to increased intra-articular pressure in the hip joint.



¨ Isotonic Ex in gravity lessened -> Isotonic Ex against gravity.

¨ Include concentric & eccentric contractions.

¨ Weight bearing and non-weight bearing activities can be used in combination based on the patient’s ability and goals of the treatment session.



¨ Upper extremity supported functional dynamic single limb activities may be performed.– e.g. step ups, side steps

¨ Double limb closed chain ex may be used with light resistance if weight bearing allows. – e.g. mini-squats


Strengthening Ex (CLIPer score 0 to 5)¨ Isotonic Ex in gravity lessened ->

Isotonic Ex against gravity. ¨ Include concentric & eccentric

contractions. ¨ Functional dynamic single limb

activities with UE support as needed for patient safety may be performed.– e.g. step ups, sidesteps

¨ Closed kinetic chain single limb exercises with light resistance may be performed. – E.g. leg press


Strengthening Ex Prescription ¨ Special attention should be given

to: – Hip abductors (especially gluteus

medius) – Hip internal rotators – Hip external rotators – Hip flexors – Hip extensors


Isometric Strengthening

¨ Parameters –– 10 sec hold + 10 rep/muscle gr, total

= 100 sec. – Can adjust hold time to 5 sec + 20

rep to meet 100 sec requirement ¨ Intensity –

– Performed at approx. 75% maximal contraction

¨ Performed with hip in neutral position


Isotonic Strengthening

¨ Parameters –– High repetitions (10 to 15 reps) and 2

to 3 sets – Perform both concentric & eccentric

contraction– Low resistance

• Rest 1 to 3 minutes between sets • Rest can include exercise of a different

muscle group or cessation of activity ¨ If pt is unable to perform 2 sets of 10

rep, exercise intensity should be decreased either through weight or type of exercise


Balance training (CLIPer score 14 – 24)

¨ If weight bearing status & symptoms allow –– Activities that include double limb

stance and a narrowed base of support on stable surfaces may be performed.

¨ It is not recommended to perform single limb activities due to increased intra-articular pressure in the hip joint.


Balance training (CLIPer score 6 – 13 & 0 – 5)

¨ Same as previous stage¨ Limit prolonged single limb

activities due to excessive joint compressive forces


Gait training (CLIPer Score 14 – 24)

¨ Follow the referring physician’s guidelines for weight bearing status.

¨ Begin gait training with –– Appropriate assistive device – Weight bearing status as determined

by the referring physician or– Based on the patient’s tolerance to

full weight bearing due to pain or safety



¨ Continue to follow the referring physician’s guidelines for weight bearing status.

¨ Progress to gait training without use of an assistive device as appropriate, focusing on minimizing deficits and improving efficiency of walking.

¨ Stair negotiation and other functional mobility.



¨ Continue to follow the referring physician’s guidelines for weight bearing status

¨ Progress to gait training without the use of an assistive device as appropriate, focusing on minimizing deficits and improving the efficiency of walking.

¨ Stair negotiation & other functional mobility.

¨ Progress to walking on uneven surfaces with an emphasis on safety.


Weight Relief

¨ The load on the hip can basically be relieved by the following methods:– Bed rest– Wheelchair– Walking with crutches,– Bracing devices (Thomas splint ,

Mainz orthosis, etc.).


Petrie Cast


Broomstick Cast


Bracing


Discharge Criteria

¨ Children may be discharged when 4 of the 5 following criteria have been met: – Pain rating 0 to 1/10 – ROM 90 to 100% of the uninvolved

side – Strength 90 to 100% of the uninvolved

side – Balance 90 to 100% of the max score

on the Pediatric Balance Scale or maintaining balance with SLS 90 to 100% of the uninvolved side

– Gait presents with a non-painful limp and uses a reciprocal pattern on the stairs.


Prognosis

¨ 60% of kids do well without Rx¨ AGE is key prognostic factor:

– <6y – good outcome regardless of Rx– 6-8y – not always good results with

just containment– >9y – containment option is

questionable, poorer prognosis, significant residual defect


Operative Tx

¨ If non-op Rx cannot maintain containment

¨ Surgically ideal pt:– 6-9yo– Catterral II-III– Good ROM– <12mos sx– In collapsing phase


Surgical Tx

¨ Surgical options:– Excise lateral extruding head portion

to stop hinging abduction– Acetabular osteotomy to cover head– Varus femoral osteotomy– Arthrodesis


Varus Osteotomy


Head at risk signs¨ Clinical features:

– Progressive loss of movement

– Adduction contractures

– Flexion in abduction

– Heavy child

¨ Radiological features:– Lateral subluxation of

the femoral head (head partially uncovered)

– Entire femoral head involved

– Calcification lateral to the epiphysis

– Metaphyseal cysts– Gage's sign


References:¨ Lee J, Allen M, Hugentobler K, Kovacs

C, Monfreda J, Nolte B, Woeste E; Evidence-Based Care Guideline Conservative Management of Legg-Calve-Perthes Disease In children aged 3 to 12 years, Cincinnati children’s hospital medical center, 2011

¨ Benjamin Joseph, Paediatric Orthopaedics, A System Of Decision-making, 2009

¨ Fritz Hefti, Pediatric Orthopedics in Practice, 2007

¨ David Wilson (Ed.), Paediatric Musculoskeletal Disease With an Emphasis on Ultrasound, 2005


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