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789
Indications for Radiography Patients with Acute Ankle Role of the Physical
.;.
.J
Ann G. Auletta1 William Curtis
Donald Alfred
Examination
____
#{149},A1 .
A prospective study was performed to test the hypothesis that a thorough physical examination can eliminate the need for a large number of radiographs obtained in patients with acute ankle trauma. Two hundred one patients were seen in the emergency department for acute ankle trauma and referred to the department of radiology for ankle radiographs. Radiology residents performed a brief but thorough physical examination of the ankle in all 201 patients. Solely on the basis of a strict set of physical examination criteria (examination for gross deformity, instability, crepitation, focal bony tenderness, severe soft-tissue tenderness, moderate or severe soft-tissue swelling, and ecchymosis), the radiologists determined whether or not the radiographs were indicated. All patients, irrespective of the physical examination, underwent ankle radiography, and the results were correlated with those of the physical examination. On the basis of the results of the physical examinations, 101 (50%) of the radiologic studies were not indicated. In only one of these patients was a fracture seen on radiographs. The radiograph in this case showed a small avulsion fracture of the dorsal aspect of the talus that was clinically insignificant (no cast or surgery was required). Our results suggest that a brief but thorough physical examination can eliminate the need for a large percentage of radiographs ordered in patients with acute ankle trauma.
F. Conway1 W. Hayes1
F. Guisto2 S.
in Injuries:
Gervin2
AJR
157:789-791,
According injuries
October
to studies
account
1991
published
in both the United States and Great Britain, ankle
for approximately
10% of all visits
to the emergency
department
[i , 2]. Ankle fractures are detected in approximately 13% of these cases [3, 4]. Consensus is growing that the radiologic evaluation of the injured ankle has superseded the physical examination as the method to detect fractures in many institutions,
and
particularly
in crowded
inner-city
emergency
departments
Reasons for this change in medical practice include the large number lack of follow-up, expectations of patients, and medicolegal concerns
[5].
of patients, [6-8]. Con-
sequently, we undertook a prospective study to determine if a brief but thorough physical examination could reduce the need for radiologic examinations in patients
with acute ankle trauma. Received January 28, 1991 ; accepted
vision
April
Presented
Roentgen 1990. I
after re-
Subjects
16, 1991. at the annual
Ray Society,
Department
meeting
Washington,
of Radiology,
Box
tion, Medical College of Virginia, 23298-0615.
Address
of the American
reprint
DC, May
615 MCV StaRichmond,
requests
to W.
VA F.
Conway. 2 Department of Surgery, Medical College of Virginia, Richmond, VA 23298. 0361 -803X/91/1
574-0789
C American Roentgen Ray Society
The
and Methods
study
group
consisted
of 201
patients
who
were
referred
from
a level
I trauma
emergency department to the radiology department for ankle radiographs from April to August 1989. There were i 09 men and 92 women 11-72 years old (average, 32 years). Of the 201 patients, 151 were examined by resident clinical physicians (with varying degrees of orthopedic experience) in the emergency department before referral to radiology. Forty-five
patients
were referred
directly
to radiology
by nonphysician
triage
an examination by a physician. In five cases, it was unclear if a physician patient before referral to radiology. Only patients who had ankle trauma department were included. In addition,
personnel
without
had examined
the
for less than 24 hr before coming to the emergency only patients who were fully alert, English speaking,
790
AULETTA
ab-
ofthe
findings, open wounds, possible septic joints, or a history of malignancy or diabetes mellitus were excluded. Once in the radiology department, patients were reinterviewed and reexamined by the radiology resident (1 0 first- and second-year residents were involved in the study). These residents were unaware of the results of any physical examination that might have been performed by emergency department personnel prior to referral for radiographs. Before the study, radiology residents were given formal instruction in the inspection and palpation of the traumatized ankle. Despite its
bony
and not pregnant normal
Downloaded from www.ajronline.org by 198.252.15.206 on 03/02/15 from IP address 198.252.15.206. Copyright ARRS. For personal use only; all rights reserved
ET AL.
were included.
Patients
with multiple
trauma,
neurovascular
thoroughness, patient,
this examination,
required
including
a brief interview
of the
less than 5 mm to perform.
Gross deformity, instability severe soft-tissue tenderness,
or crepitation, focal bony tenderness, moderate or severe soft-tissue swell-
ing, and ecchymosis were all considered cally significant injuries. Special attention
indicative of potential cliniwas given to distinguishing
bony from soft-tissue tenderness. The deltoid, fibulocalcaneal, and anterior and posterior talofibular ligaments were all individually palpated, as were the lateral and medial malleoli, the base of the fifth metatarsal, and the dorsal talus. In both the initial physical examination and final radiologic evaluation, ankle injuries were considered clinically significant if the injury required open or closed manipulation and/or long-term immobilization in a cast. At our institution, this includes mostly fractures and dislocations, because acute ligamentous injuries are not treated surgically and are only rarely treated by immobilization in a cast. Clinically
medications,
and/or
resident
was
required
to indicate,
before the radiographs injury
was suspected,
(3)
suspected, was
were
present,
made
(2) a clinically
examination,
significant
significant
soft-tissue injury
was
was
suspected.
If
resident believed that a clinically significant injury was present (whether it was of bony or soft-tissue origin) or was uncertain, the patient was classified as having adequate indications for radioginjury
was
present,
indications
resident
the
patient
for radiography.
believed that no clinically significant classified as having inadequate The residents were instructed to be was
conservative in their evaluations and were told significant injury meant that they were confident
physical examination received lateral,
that no significant
of the evaluation
Regardless
a full set of ankle radiographs and mortise
views.
who
blinded
radiologist
For purposes
was
All studies
to the results
of the radiograph
as clinically significant
resident,
including
all patients
anteroposterior,
were then evaluated
of this study, outcome
the interpretation
that no clinically by virtue of the
injury was present.
by the radiology
of the
physical
was considered and categorization
evidence
treated
of significant
conservatively.
who were to radiology,
actually examined by a 74 (49%) were classified
as having adequate indications for radiographs of the ankle. Twenty-three (31 %) of those patients had an injury that required orthopedic intervention. Seventy-seven patients (51 %) were classified as having inadequate indications for radiographs
(all of these
patients
had
injuries
that
could
be
treated conservatively). This group included the previously described patient with an avulsion fracture of the dorsal talus. Forty-five patients (22%) were sent directly to radiology by nonphysician
triage
examination.
Twenty-one
indications
personnel
without
(47%)
for radiographs;
the benefit
of these
patients
of this group,
of physical
had ade-
six (29%)
had
significant
injury requiring orthopedic intervention. Twenty-four patients (53%) were classified as having madequate indications for ankle radiographs. None of these had clinically significant injuries.
Discussion
bony
injury
the radiology
raphy. If the radiology
and were
questionnaire
if (1) a clinically
was unclear whether a clinically significant injury
it
or (4) no clinically
injury
the radiology
on a preprinted significant
had no radiographic
Of the 1 51 patients physician before referral
a clinically
an Ace wrap.
Solely on the basis of the physical
100 patients or soft-tissue
1991
One hundred one patients (50%) were classified as having inadequate indications for radiographs of the ankle on the basis of the physical examination. Of these, only one had a fracture; this was a minimal avulsion fracture of the dorsal aspect of the talus that was treated conservatively. The remaining 1 00 patients had no radiologic evidence of a signifcant bony or soft-tissue injury.
quate
insignificant injuries were those that were treated conservatively, that is, with weight-bearing as tolerated, elevation, nonsteroid antiinflammatory
AJA:1 57, October
by a staff
examination.
complete
with of the findings
or insignificant.
Only half of the patients who were referred for ankle radiography had a physical examination performed by radiology residents that indicated a need for ankle radiographs. No patients in whom indications for radiography were inadequate on the basis of the radiologist’s physical examination had a clinically significant ankle injury (95% confidence interval:
.960, 1 .0 [9]). In none of these cases did radiographs change the clinical management. These findings suggest that a brief but thorough physical examination can eliminate the need for a large percentage of ankle radiographs in patients with acute ankle injuries.
It is important to note that some patients who presented to the emergency department with acute ankle trauma were never sent for radiographs. Emergency department physicians believed the injuries in these patients were insignificant, and they were treated conservatively. Additionally, clinicians (with the exception of the chairman of the emergency department) were unaware that the study was ongoing. This prevented unintentional bias in the patient referral pattern for
Results
radiography, but it also led to incomplete record keeping. Thus, we do not know the exact number of patients treated
On the basis of the results of physical examination, 100 of the 201 patients in this study had adequate indications for ankle radiography. Of these patients, 30 (30%) had an abnormality on the radiographs that required manipulation and/or immobilization in a cast. Twenty-nine had fractures, and one had a chronic tear of the deltoid ligament that was acutely
without the diagnostic aid of radiographs. We were also unable to ascertain the criteria used by emergency department personnel in ordering radiographs. Approximately 75% of the patients were referred for ankle
exacerbated
soft-tissue
and
required
casting.
injury that led to orthopedic
No
other
patient
intervention.
had
Seventy
a
radiographs
after
examination
by a resident
emergency
de-
partment physician. Radiographs on the others were requested by nonphysician triage personnel without the aid of a physical examination. No significant difference was found
Downloaded from www.ajronline.org by 198.252.15.206 on 03/02/15 from IP address 198.252.15.206. Copyright ARRS. For personal use only; all rights reserved
AJA:157, October 1991
ROLE
OF
RADIOGRAPHY
in the percentage of indicated studies ordered by these two groups (51 % vs 53%, respectively; 95% confidence interval: 0.197, -0.1 57 [9]). In addition, no difference was seen in the percentage of clinically significant injuries detected on radiographs (1 5% vs 1 3%, respectively; 95% confidence interval: 0.145, -0.105 [9]). These data suggest that either the emergency department physician performed an inadequate physical examination or failed to act on the results of an adequate examination. DeLacey et al. [1 ] stated that if the maxim of “no swelling, no radiographs” were applied, the number of radiographs of the ankle could be reduced by two thirds. Our study indicates that if a policy of “no significant physical examination findings, no radiographs” had been implemented, the number of radiographs in this specific patient population could have been reduced by 50%. Overall reduction probably would have been lower if all patients (i.e., multiple trauma) had been included in the study. Many studies, in both the United States and Great Britain [1 , 3-6, 1 0-1 2], have addressed the issue of overuse of radiology in the evaluation of acute ankle trauma. Yet, these studies have had limited impact on clinical practice; overuse of ankle radiographs in patients with acute ankle trauma persists. This issue takes on special significance in this day of cost containment and limited resources. The cost in terms of money, radiation exposure, and decreased efficiency is substantial. Even though the study was performed by radiologists, we do not advocate that radiologists routinely take medical histones and perform physical examinations on patients with traumatized ankles. Rather, we think that clinical physicians or physicians’ assistants, with their additional clinical training and experience, should be performing this task. It must be
IN ANKLE
TRAUMA
791
emphasized, however, that whoever performs the physical examination should be well trained in its intricacies. Without such training, accuracy is limited. In conclusion, our study confirms that requesting radiographs on the basis of a properly performed physical examination can substantially reduce the number of radiographs obtained for evaluation of acute ankle trauma without affecting the quality of patients’ care.
REFERENCES 1 . DeLacey
GJ, Bradbrooke
S. Rationalizing
requests
for x-ray
examination
of acute ankle injury. Br Med J 1979;1 :1597-1598 Ferguson DG. Why do accident and emergency doctors Arch Emerg Med 1984;3: 143-150 3. Cockshott WB, Jenken JK, Pui M. Limiting the use of routine radiography for acute ankle injuries. Can Med Assoc J 1983;129: 129-131 2. Warren
RA,
request x-rays?
4. Dunlop MG, Beattie TF, White Gl, Aaab GM, Doull RI. Guidelines for selective radiological assessment of inversion ankle injuries. Br Med J 1986;293:603-605 5. Vargish T, Clarke WA, Young AA, Jensen A. The ankle injury-indications for the selective use of x-rays. Injury 1982;14:507-512 6. Brand DA, Frazier WH, Kohlhepp WC, et al. A protocol for selecting patients with injured extremities who need x-rays. N EngI J Med
1982;306:333-339 7. Hall FM. Overutilization of radiologic examination. Radiology 1978; 120:443-448 8. Grover K. X-ray examination for legal protection. JAMA 1980244:14361437 9. Berry CC. A tutorial on confidence intervals for proportions in diagnostic radiology. AJR 1990;154:477-480 1 0. Brooks SC, Potter BT, Rainey JB. Inversion injuries of the ankle: clinical assessment and radiographic review. Br Med J 1981:282:607-608 11 . Garfield JS. Is radiological examination of the twisted ankle necessary? Lancet 19602:1167-1169 1 2. Montague AP, McQuillan AF. Clinical assessment of apparently sprained ankle and detection of fracture. Injury 1985:545-546
789
Indications for Radiography Patients with Acute Ankle Role of the Physical
.;.
.J
Ann G. Auletta1 William Curtis
Donald Alfred
Examination
____
#{149},A1 .
A prospective study was performed to test the hypothesis that a thorough physical examination can eliminate the need for a large number of radiographs obtained in patients with acute ankle trauma. Two hundred one patients were seen in the emergency department for acute ankle trauma and referred to the department of radiology for ankle radiographs. Radiology residents performed a brief but thorough physical examination of the ankle in all 201 patients. Solely on the basis of a strict set of physical examination criteria (examination for gross deformity, instability, crepitation, focal bony tenderness, severe soft-tissue tenderness, moderate or severe soft-tissue swelling, and ecchymosis), the radiologists determined whether or not the radiographs were indicated. All patients, irrespective of the physical examination, underwent ankle radiography, and the results were correlated with those of the physical examination. On the basis of the results of the physical examinations, 101 (50%) of the radiologic studies were not indicated. In only one of these patients was a fracture seen on radiographs. The radiograph in this case showed a small avulsion fracture of the dorsal aspect of the talus that was clinically insignificant (no cast or surgery was required). Our results suggest that a brief but thorough physical examination can eliminate the need for a large percentage of radiographs ordered in patients with acute ankle trauma.
F. Conway1 W. Hayes1
F. Guisto2 S.
in Injuries:
Gervin2
AJR
157:789-791,
According injuries
October
to studies
account
1991
published
in both the United States and Great Britain, ankle
for approximately
10% of all visits
to the emergency
department
[i , 2]. Ankle fractures are detected in approximately 13% of these cases [3, 4]. Consensus is growing that the radiologic evaluation of the injured ankle has superseded the physical examination as the method to detect fractures in many institutions,
and
particularly
in crowded
inner-city
emergency
departments
Reasons for this change in medical practice include the large number lack of follow-up, expectations of patients, and medicolegal concerns
[5].
of patients, [6-8]. Con-
sequently, we undertook a prospective study to determine if a brief but thorough physical examination could reduce the need for radiologic examinations in patients
with acute ankle trauma. Received January 28, 1991 ; accepted
vision
April
Presented
Roentgen 1990. I
after re-
Subjects
16, 1991. at the annual
Ray Society,
Department
meeting
Washington,
of Radiology,
Box
tion, Medical College of Virginia, 23298-0615.
Address
of the American
reprint
DC, May
615 MCV StaRichmond,
requests
to W.
VA F.
Conway. 2 Department of Surgery, Medical College of Virginia, Richmond, VA 23298. 0361 -803X/91/1
574-0789
C American Roentgen Ray Society
The
and Methods
study
group
consisted
of 201
patients
who
were
referred
from
a level
I trauma
emergency department to the radiology department for ankle radiographs from April to August 1989. There were i 09 men and 92 women 11-72 years old (average, 32 years). Of the 201 patients, 151 were examined by resident clinical physicians (with varying degrees of orthopedic experience) in the emergency department before referral to radiology. Forty-five
patients
were referred
directly
to radiology
by nonphysician
triage
an examination by a physician. In five cases, it was unclear if a physician patient before referral to radiology. Only patients who had ankle trauma department were included. In addition,
personnel
without
had examined
the
for less than 24 hr before coming to the emergency only patients who were fully alert, English speaking,
790
AULETTA
ab-
ofthe
findings, open wounds, possible septic joints, or a history of malignancy or diabetes mellitus were excluded. Once in the radiology department, patients were reinterviewed and reexamined by the radiology resident (1 0 first- and second-year residents were involved in the study). These residents were unaware of the results of any physical examination that might have been performed by emergency department personnel prior to referral for radiographs. Before the study, radiology residents were given formal instruction in the inspection and palpation of the traumatized ankle. Despite its
bony
and not pregnant normal
Downloaded from www.ajronline.org by 198.252.15.206 on 03/02/15 from IP address 198.252.15.206. Copyright ARRS. For personal use only; all rights reserved
ET AL.
were included.
Patients
with multiple
trauma,
neurovascular
thoroughness, patient,
this examination,
required
including
a brief interview
of the
less than 5 mm to perform.
Gross deformity, instability severe soft-tissue tenderness,
or crepitation, focal bony tenderness, moderate or severe soft-tissue swell-
ing, and ecchymosis were all considered cally significant injuries. Special attention
indicative of potential cliniwas given to distinguishing
bony from soft-tissue tenderness. The deltoid, fibulocalcaneal, and anterior and posterior talofibular ligaments were all individually palpated, as were the lateral and medial malleoli, the base of the fifth metatarsal, and the dorsal talus. In both the initial physical examination and final radiologic evaluation, ankle injuries were considered clinically significant if the injury required open or closed manipulation and/or long-term immobilization in a cast. At our institution, this includes mostly fractures and dislocations, because acute ligamentous injuries are not treated surgically and are only rarely treated by immobilization in a cast. Clinically
medications,
and/or
resident
was
required
to indicate,
before the radiographs injury
was suspected,
(3)
suspected, was
were
present,
made
(2) a clinically
examination,
significant
significant
soft-tissue injury
was
was
suspected.
If
resident believed that a clinically significant injury was present (whether it was of bony or soft-tissue origin) or was uncertain, the patient was classified as having adequate indications for radioginjury
was
present,
indications
resident
the
patient
for radiography.
believed that no clinically significant classified as having inadequate The residents were instructed to be was
conservative in their evaluations and were told significant injury meant that they were confident
physical examination received lateral,
that no significant
of the evaluation
Regardless
a full set of ankle radiographs and mortise
views.
who
blinded
radiologist
For purposes
was
All studies
to the results
of the radiograph
as clinically significant
resident,
including
all patients
anteroposterior,
were then evaluated
of this study, outcome
the interpretation
that no clinically by virtue of the
injury was present.
by the radiology
of the
physical
was considered and categorization
evidence
treated
of significant
conservatively.
who were to radiology,
actually examined by a 74 (49%) were classified
as having adequate indications for radiographs of the ankle. Twenty-three (31 %) of those patients had an injury that required orthopedic intervention. Seventy-seven patients (51 %) were classified as having inadequate indications for radiographs
(all of these
patients
had
injuries
that
could
be
treated conservatively). This group included the previously described patient with an avulsion fracture of the dorsal talus. Forty-five patients (22%) were sent directly to radiology by nonphysician
triage
examination.
Twenty-one
indications
personnel
without
(47%)
for radiographs;
the benefit
of these
patients
of this group,
of physical
had ade-
six (29%)
had
significant
injury requiring orthopedic intervention. Twenty-four patients (53%) were classified as having madequate indications for ankle radiographs. None of these had clinically significant injuries.
Discussion
bony
injury
the radiology
raphy. If the radiology
and were
questionnaire
if (1) a clinically
was unclear whether a clinically significant injury
it
or (4) no clinically
injury
the radiology
on a preprinted significant
had no radiographic
Of the 1 51 patients physician before referral
a clinically
an Ace wrap.
Solely on the basis of the physical
100 patients or soft-tissue
1991
One hundred one patients (50%) were classified as having inadequate indications for radiographs of the ankle on the basis of the physical examination. Of these, only one had a fracture; this was a minimal avulsion fracture of the dorsal aspect of the talus that was treated conservatively. The remaining 1 00 patients had no radiologic evidence of a signifcant bony or soft-tissue injury.
quate
insignificant injuries were those that were treated conservatively, that is, with weight-bearing as tolerated, elevation, nonsteroid antiinflammatory
AJA:1 57, October
by a staff
examination.
complete
with of the findings
or insignificant.
Only half of the patients who were referred for ankle radiography had a physical examination performed by radiology residents that indicated a need for ankle radiographs. No patients in whom indications for radiography were inadequate on the basis of the radiologist’s physical examination had a clinically significant ankle injury (95% confidence interval:
.960, 1 .0 [9]). In none of these cases did radiographs change the clinical management. These findings suggest that a brief but thorough physical examination can eliminate the need for a large percentage of ankle radiographs in patients with acute ankle injuries.
It is important to note that some patients who presented to the emergency department with acute ankle trauma were never sent for radiographs. Emergency department physicians believed the injuries in these patients were insignificant, and they were treated conservatively. Additionally, clinicians (with the exception of the chairman of the emergency department) were unaware that the study was ongoing. This prevented unintentional bias in the patient referral pattern for
Results
radiography, but it also led to incomplete record keeping. Thus, we do not know the exact number of patients treated
On the basis of the results of physical examination, 100 of the 201 patients in this study had adequate indications for ankle radiography. Of these patients, 30 (30%) had an abnormality on the radiographs that required manipulation and/or immobilization in a cast. Twenty-nine had fractures, and one had a chronic tear of the deltoid ligament that was acutely
without the diagnostic aid of radiographs. We were also unable to ascertain the criteria used by emergency department personnel in ordering radiographs. Approximately 75% of the patients were referred for ankle
exacerbated
soft-tissue
and
required
casting.
injury that led to orthopedic
No
other
patient
intervention.
had
Seventy
a
radiographs
after
examination
by a resident
emergency
de-
partment physician. Radiographs on the others were requested by nonphysician triage personnel without the aid of a physical examination. No significant difference was found
Downloaded from www.ajronline.org by 198.252.15.206 on 03/02/15 from IP address 198.252.15.206. Copyright ARRS. For personal use only; all rights reserved
AJA:157, October 1991
ROLE
OF
RADIOGRAPHY
in the percentage of indicated studies ordered by these two groups (51 % vs 53%, respectively; 95% confidence interval: 0.197, -0.1 57 [9]). In addition, no difference was seen in the percentage of clinically significant injuries detected on radiographs (1 5% vs 1 3%, respectively; 95% confidence interval: 0.145, -0.105 [9]). These data suggest that either the emergency department physician performed an inadequate physical examination or failed to act on the results of an adequate examination. DeLacey et al. [1 ] stated that if the maxim of “no swelling, no radiographs” were applied, the number of radiographs of the ankle could be reduced by two thirds. Our study indicates that if a policy of “no significant physical examination findings, no radiographs” had been implemented, the number of radiographs in this specific patient population could have been reduced by 50%. Overall reduction probably would have been lower if all patients (i.e., multiple trauma) had been included in the study. Many studies, in both the United States and Great Britain [1 , 3-6, 1 0-1 2], have addressed the issue of overuse of radiology in the evaluation of acute ankle trauma. Yet, these studies have had limited impact on clinical practice; overuse of ankle radiographs in patients with acute ankle trauma persists. This issue takes on special significance in this day of cost containment and limited resources. The cost in terms of money, radiation exposure, and decreased efficiency is substantial. Even though the study was performed by radiologists, we do not advocate that radiologists routinely take medical histones and perform physical examinations on patients with traumatized ankles. Rather, we think that clinical physicians or physicians’ assistants, with their additional clinical training and experience, should be performing this task. It must be
IN ANKLE
TRAUMA
791
emphasized, however, that whoever performs the physical examination should be well trained in its intricacies. Without such training, accuracy is limited. In conclusion, our study confirms that requesting radiographs on the basis of a properly performed physical examination can substantially reduce the number of radiographs obtained for evaluation of acute ankle trauma without affecting the quality of patients’ care.
REFERENCES 1 . DeLacey
GJ, Bradbrooke
S. Rationalizing
requests
for x-ray
examination
of acute ankle injury. Br Med J 1979;1 :1597-1598 Ferguson DG. Why do accident and emergency doctors Arch Emerg Med 1984;3: 143-150 3. Cockshott WB, Jenken JK, Pui M. Limiting the use of routine radiography for acute ankle injuries. Can Med Assoc J 1983;129: 129-131 2. Warren
RA,
request x-rays?
4. Dunlop MG, Beattie TF, White Gl, Aaab GM, Doull RI. Guidelines for selective radiological assessment of inversion ankle injuries. Br Med J 1986;293:603-605 5. Vargish T, Clarke WA, Young AA, Jensen A. The ankle injury-indications for the selective use of x-rays. Injury 1982;14:507-512 6. Brand DA, Frazier WH, Kohlhepp WC, et al. A protocol for selecting patients with injured extremities who need x-rays. N EngI J Med
1982;306:333-339 7. Hall FM. Overutilization of radiologic examination. Radiology 1978; 120:443-448 8. Grover K. X-ray examination for legal protection. JAMA 1980244:14361437 9. Berry CC. A tutorial on confidence intervals for proportions in diagnostic radiology. AJR 1990;154:477-480 1 0. Brooks SC, Potter BT, Rainey JB. Inversion injuries of the ankle: clinical assessment and radiographic review. Br Med J 1981:282:607-608 11 . Garfield JS. Is radiological examination of the twisted ankle necessary? Lancet 19602:1167-1169 1 2. Montague AP, McQuillan AF. Clinical assessment of apparently sprained ankle and detection of fracture. Injury 1985:545-546
