- The Ottawa clinical decision rules provide guidelines for doctors to determine if x-rays are needed for patients presenting with ankle, foot, or knee injuries. - Previously, most patients would receive x-rays but only 15% revealed fractures, resulting in many unnecessary x-rays. - This study prospectively validated the rules in over 2500 patients in India. It found the rules to be highly sensitive for detecting fractures while allowing for a 32% reduction in unnecessary x-rays. - Applying the rules correctly identified fractures in 95.6% of ankle, 98% of foot, and 100% of knee cases while avoiding many x-rays not needed. This decreased wait times and costs while avoiding potential health risks

1. Ottawa Clinical Decision Rule
- A Prospective, Validation Study for use of
Radiography in Acute Ankle, Mid Foot and
Knee Injuries in the ED, South India.
SRMC&RI
Dr. Srihari. Cattamanchi., M.D. (A&EM).
Sri Ramachandra Medical College & Research Institute,
Chennai . India

2. Background
• The Ottawa clinical decision rules are a set of
guidelines for doctors to aid them in deciding if a
patient with ankle, foot or knee pain should be offered
x-rays to diagnose a possible bone fractures.
• Before the introduction of the rules most patients with
ankle, foot or knee injuries would have been x-rayed.

3. Background
• However only about 15% of X-rays were
positive for fracture, other patients had sprains
or other injuries.
• As a result many unnecessary X-rays were
taken, which was costly, time consuming and a
possible health risk.

4. Ottawa rules for x-ray of ankle
An ankle x-ray is required only if there is any pain in
Malleolar zone and any of these findings:
– age 55 or over
– bone tenderness at posterior edge or tip of lateral
malleolus
– bone tenderness at posterior edge or tip of medial
malleolus
– inability to weight bear both immediately and in ED

5. Ottawa rules for x-ray of ankle & Foot

6. Ottawa rules for x-ray of foot
A foot x-ray is required if there is any pain in the
Midfoot zone and any of these findings:
– age 55 or over
– bone tenderness at Base of 5th Metatarsal
– bone tenderness at Navicular
– inability to weight bear both immediately and in the
emergency department.

7. Ottawa rules for x-ray of ankle & Foot

8. Ottawa rules for x-ray of knee
A knee x-ray is only required for knee injury patients
with any of these findings:
– age 55 or over
– isolated tenderness of the patella
– tenderness at the head of the fibula
– inability to flex to 90 degrees
– inability to weight bear both immediately and in the
emergency department.

9. Objectives
To determine the sensitivity and specificity of the
Ottawa clinical decision rules.
To determine whether use of the rule would reduce the
number of radiographs ordered.

10. Materials & Methods
Design: A prospective, analytical, validation study
Setting: Done at an academic ED of Sri Ramachandra
Medical College & Research Institute, a tertiary care
university hospital, & Level I trauma center, in South
India.
Duration: Between June 1st 2008 and December 31st
2009.

11. Materials & Methods
Inclusion Criteria:
– All patients registered in the ED,
– above 2 years of age,
– sustained Ankle, Foot or Knee injury in
preceding 7 days, and
– evidence of bony injury on physical
examination.

12. Materials & Methods
Exclusion Criteria:
– Paraplegic patients,
– pregnant,
– altered sensorium,
– polytrauma or
– other major fractures.

13. Sampling: A consecutive sampling technique .
Statistical analysis: Sensitivity, specificity & 95%
confidence interval done with SPSS Ver.17.0
Instrument: A preformatted proforma was used.
Materials & Methods

15. Results – Age & Sex
Distribution
0
50
100
150
200
250
1 - 10
Years
11 - 20
Years
21 - 30
Years
31 - 40
Years
41 - 50
Years
51 - 60
Years
61 - 70
Years
71 - 80
Years
> 80
Years
NoofPatients
Male - 671
Female - 258

16. Mechanism of Injury
277
201
451
Direct Blow
Torsion
Other indirect
injury

17. Causes of Injury
74
224
502
17
112
Sports Injury
Fall Related Injury
Road Traffic
Accidents
Assault
Industrial
Accidents

18. Injuries Sustained
205
325
399 Ankle
Foot
Knee

19. History
239
43
690
656
0 100 200 300 400 500 600 700 800
Cracking / Popping Sound Heard
Lower Limb Injury in Preceding
year
Able to Bear weight
Immediately
Able to continue activity being
performed at time of Injury

20. Range of Motion
612
317
Full
Restricted

21. Ability to Bear Weight – 4 Steps in ED
690
239
Yes
No

22. Bone Tenderness of Ankle Joint
13
16
4
9
7
13
0
2
4
6
8
10
12
14
16
18
Lateral Malleolus Medial Malleolus
NoofPatients
Anterior Edge Inferior Tip Posterior Edge

23. Bone Tenderness of Foot
21
57
24
Fig. 13. Bone Tenderness of the Foot
Cuboid Navicular Base of Fifth Metatarsal

24. Bone Tenderness of Knee Joint
22
36 39 44
55
33
60
43
0
10
20
30
40
50
60
70
Patella Isolated
Patella
Patella &
Direct
Below
Medial
Femoral
Condyle
Lateral
Femoral
Condyle
Medial TibiaLateral Tibia Tibial
Tuberosity
NoofPatients

25. Prospective Prediction of
Ottawa Clinical Decision Rule
87
113
81
118
212
318
0
50
100
150
200
250
300
350
Ankle Foot Knee
NoofPatients
Fracture No Fracture

26. Radiographs Ordered
632
769
1224
Ankle
Foot
Knee
N = 2625

27. Fracture Yield
• Fractures Detected
• 69 ankle fractures,
• 104 midfoot fractures and
• 66 knee fractures.
• Fracture Yield
• 10.9% for ankle films,
• 13.5% for foot films and
• 5.4% for knee films.

28. Radiological Findings
136
221
333
69
104
66
0
50
100
150
200
250
300
350
Ankle Foot Knee
NoofPatients
Normal Study Signigicant Fracture

29. Missed Fractures
Rule failed to predict fracture in 3 ankle injuries
and 2 midfoot injuries
Two were distal fibula fractures and one was
distal tibia fracture.
Two missed midfoot fractures were of 5th
metatarsal and calcaneus.
The examiner’s clinical impression was no
fracture.

30. Disposition
333
487
28
81
Discharged Admitted to Ward Admitted to ICU / Immediate Surgery DAMA

31. Sensitivity, Specificity & Negative predictive
value of rule in ankle, foot & knee injuries.
Parameters1 Ankle Foot Knee
Sensitivity 95.6% 98% 100%
Specificity 86.7% 95.5% 95.7%
Negative Predictive
value
97.5% 99% 100%
Positive Predictive
Value
78.5% 91.8% 82.5%
Potential Radiographic
Savings
57.5% 65.2% 79.6%

32. Limitations
Study population - convenience sample of eligible
patients.
May have introduced selection bias toward patients with
more severe injury.
This is suggested by our relatively high fracture yields for
ankle and mid-foot injuries.
Examination accuracy may have varied among
examiners.
Inter-rater reliability not assessed.

33. Conclusion
Prospective validation has shown Ottawa Rules to be
100% sensitive for identifying fractures of knee.
However, their sensitivity is not 100% in ankle and foot
injuries.
Appears to be much more sensitive than clinical
impression

34. Conclusion
May be used as a guideline for selectively ordering
radiographs in acute ankle, foot and knee injury.
Application of the rule would have led to a 32% relative
reduction in use of radiography in the ED.
This would inturn decrease waiting times for patients
discharged without radiography by 55 minutes in this
study.

35. Thank You

36. My friends & Colleagues

37. My friends & Colleagues