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Rheumatoid Arthritis | Index for Quantifying Joint Inflammation & Deformity

Purpose: To evaluate the severity of peripheral joint involvement in a patient with rheumatoid arthritis using the index of Lansbury and Haut.

Description

Lansbury and Haut developed an index for evaluating total joint involvement in peripheral joints of a patient with rheumatoid arthritis. This can be used to monitor a patient over time and to monitor the effect of therapeutic interventions. The authors are from Temple University in Philadelphia.


Joints examined: non-axial joints in the left and right upper and lower extremities

 

Number of joints in an upper extremity: 26

 

Number of joints in a lower extremity: 25

 

Total number of joints examined: 26 + 25 + 26 + 25 = 102

 

Percent Involvement

Severity

Percent of Maximum Points

0

none (Grade 0)

0

1 to 25%

minimal (Grade I)

25%

26 - 50%

slight (Grade II)

50%

51 - 75%

moderate (Grade III)

75%

76 - 100%

maximum (Grade IV)

100%

 

NOTE: The index was developed in the mid 1950's. Point assignments were rounded off to make calculation simpler. The actual joint area (see Table 1, page 152) and percent involvement for each joint could be determined if a more precise number is needed.

 

Joint in the Upper Extremity

Maximum Points

terminal interphalangeal #2

1

terminal interphalangeal #3

1

terminal interphalangeal #4

1

terminal interphalangeal #5

1

proximal interphalangeal #1

2

proximal interphalangeal #2

2

proximal interphalangeal #3

2

proximal interphalangeal #4

2

proximal interphalangeal #5

2

metacarpophalangeal #1

5

metacarpophalangeal #2

5

metacarpophalangeal #3

5

metacarpophalangeal #4

5

metacarpophalangeal #5

5

carpometacarpal #1

4

carpometacarpal #2

4

carpometacarpal #3

4

carpometacarpal #4

4

carpometacarpal #5

4

transverse intercarpal joints

15

wrist (radial and ulnar with carpal)

15

elbow (radial and ulnar with humeral)

52

shoulder (humeroscapular)

45

acromioclavicular

4

sternoclavicular

12

temporomandibular

4

 

subtotal score for an upper extremity =

= SUM for all joints ((percent of maximum) * (maximum points for joint))

 

Joint in the Lower Extremity

Maximum Points

terminal interphalangeal #2

0.5

terminal interphalangeal #3

0.5

terminal interphalangeal #4

0.5

terminal interphalangeal #5

0.5

proximal interphalangeal #1

3

proximal interphalangeal #2

1

proximal interphalangeal #3

1

proximal interphalangeal #4

1

proximal interphalangeal #5

1

metatarsophalangeal #1

8

metatarsophalangeal #2

5

metatarsophalangeal #3

5

metatarsophalangeal #4

5

metatarsophalangeal #5

5

tarsometatarsal #1

5

tarsometatarsal #2

5

tarsometatarsal #3

5

tarsometatarsal #4

5

tarsometatarsal #5

5

transverse intertarsals

12

talonavicular-calcaneocuboid

21

talocalcaneal

18

ankle (talus with tibia and fibular)

35

knee and patella

104

hip

82

 

subtotal score for an lower extremity =

= SUM for all joints ((percent of maximum) * (maximum points for joint))

 

total score =

= SUM(points for all 4 extremities)

 

Interpretation:

• minimum score for an extremity: 0

• maximum score for an upper extremity: 206

• maximum score for a lower extremity: 334

• maximum total score: 206 + 334 + 2-6 + 334 = 1080

• The higher the score the more severe the disease.

 

percent of maximal joint involvement =

= (total score for patient) / 1080 * 100%

 

In the original paper, the percent of maximal joint involvement was determined by placing a decimal point before the last digit (for example, 558 would be 55.8 percent).


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Specialty

Objective

ICD-10