INVERSION ANKLE
                                      Lindsay Berks

                   Pathways and Evaluations of Athletic Injuries I

                                        Dr. Sterner

Injury Identification


The ankle consist of two joints: the talar mortise and the subtalar joint. The mortise is
shaped like an inverted "U" bounded by the distal fibula and tibia. Inside then "U" is the
trapezoid-shaped talar dome; its greater anterior width gives the ankle lateral stability (4).
The subtalar joint lies inferior to the ankle joint. The end of the tibia forms the inner bony
prominence of the ankle called the medial malleolus while the outer bony prominence is
called the lateral malleolus and is formed by the tibia (5). The lateral aspect of the ankle
is also composed of a complex of three ligaments. These include the talo-fibular
ligament, which attaches from the talus to the fibula, the calcaneo-fibular ligament, which
has attachments from the calcaneus to the fibula, and the posterior talo-fibular ligament,
which attaches from the talus to the fibula. Muscles and tendons, which act as secondary
stabilizers, are also present in the foot and ankle. The peroneus brevis originates at th e
inferior 2/3 of the lateral fibular surface and inserts into the base of the fifth metatarsal,
while the peroneus longus originates at the head of the fibula and inserts into the
posterolateral aspect of the medial cuneiform and the lateral side of the base of the first
metatarsal. Both of these muscles are innervated by the superficial peroneal nerve. *See
figures 1-2


The entire ankle is a simple hinge joint. Much of the stability of this joint depends on the
supporting ligamentous structures. The subtalar joint lies inferior to the ankle joint and is
responsible for inversion and eversion of the hindfoot. This joint also controls foot
supination and pronation in close conjunction with the transverse tarsal joints of the
middle foot (4). The lateral ankle ligaments that are responsible for resistance against
inversion and internal rotation stress are the anterior talofibular ligament (ATFL), the
calcaneofibular ligaments (CFL) and the posterior talofibular ligament (PTFL). The
ATFL resists ankle inversion in plantar flexion, and the CFL resists ankle inversion
during dorsi flexion. The accessory functions of the ATFL include resistance to anterior
talar displacement from the mortise and resistance to internal rotation of the talus within
the mortise. The CFL spans both the lateral ankle joint and lateral subtalar joint, thus
contributing to b oth ankle and subtalar joint stability. The PTFL is under greatest stress
in ankle dorsi flexion and acts to limit talar displacement within the mortise as well as
talar external rotation (5). The muscles and tendons of the foot and ankle act as secondary
stabilizers and are often injured. The peroneus longus is the main everter of the ankle,
while the peroneus brevis everts the foot and plantar flexes the ankle. The anterior tibialis
acts in dorsi flexion while the posterior tibialis inverts and plantar flexes the foot. The
Achilles tendon also acts in plantar flexion (4). *See figures 3-4


Sprains of the lateral ligaments, which are much weaker then the medial ligaments, are
the most common ankle injuries in sports and in daily activities. Lateral ankle sprains, or
inversion ankle sprains, occur as a result of landing on a plantar flexed and inverted foot.
The most common injury resulting from an inversion ankle injury is a partial tear to the
anterior talo-fibular ligament. This ligament may also tear completely. The next most
frequently injured ligament is the calcaneo-fibular ligament and least injured is the
posterior talo-fibular ligament due to its impeccable strength (2). Other structures that can
be injured in an inversion ankle sprain include the peroneal tendon, which can sublux or
move in and out of place, the calcaneo-cuboid ligament and the base of the fifth
metatarsal, which can break.


The most common mechanism of lateral ankle sprain injuries is a combination of plantar
flexion and inversion. Sometime these injuries can occur while running on uneven
terrain, stepping in a hole, stepping on another athlete’s foot during play, or landing
from a jump in an unbalanced position (4).

Personal Data

The athlete is a 20-year old female who is currently in her third year at a small division
three university and she has been playing collegiate soccer since her freshman year. This
injury to the lateral aspect of her dominant right ankle was documented on October 3,


The mechanism of this injury is the result of the athlete turning her ankle on a ball while
proceeding to trap it. When the injury occurred there was no recognition of an audible
pop or sound of any kind. Following the incident the athlete was helped off the field and
could not continue playing in the remainder of the game. She was out for two weeks
following the incident. Her level of pain on a scale of 1-10 was not documented. The
athlete has a history of one previous ankle sprain.

Assessment Results

During inspection it was noted that the athlete was developing an edema over the sinus
tarsi and posterior to the medial and lateral malleoli. There was also visible ecchymosis
inferior to the medial malleolus.


During bony palpation for the indication of pain, the athlete was point tender over the
lateral malleolus. At the same time, when palpating the surrounding soft tissue, the
athlete had pain over the sinus tarsi.


Active, passive and resistive range of motion for plantar flexion was a 2 out of a possible
5 with pain. Active, passive and resistive range of motion for inversion was a 3 out of 5
with pain.


All neurological and circulation tests were within normal limits.


Five special tests were performed on the athlete which included talar tilt, anterior drawer,
kleigers, and the tap and squeeze tests. Three of the tests had negative results with
exception to the talar tilt and anterior drawer tests which both came out positive. *See
figures 5-6


Following the incident and initial inspection of the injury the athlete was referred to a
physician. There she received X-rays to rule out any possibilities of ankle or foot
fractures, lateral malleolus fractures, or Osteochondritis Dissecans, which is the
pathology where a loose piece of cartilage and bone separates from the end of the bone.
These pathologies were negative though which leads to my understanding that there were
instead visible signs of a partial tear to the ATF ligament which is indicative to a lateral
ankle sprain.


The Athletic Trainers initial response to the athletes injury was a second degree anterior
talo-fibular ankle sprain. Although I only observed the athlete a week after the occurrence
of the initial injury, it is clear that by looking at the injury report and understanding that a
mechanism of inverting the foot on an object such as a ball, is clear indication of an
inversion, or lateral ankle sprain. As far as what level of sprain this injury can be
classified as, I agree with the Athletic Trainers impression of a second degree sprain
based on these grounds. Ankle sprains are classified into three levels which are
determined by the amount of instability present during the assessment of the injury.
Giving a sprain a grade of a two is quite accurate because it assumes that there is
incomplete tearing of a ligament coupled with moderate functional impairment (1). Since
the athlete was given active, passive and resistive ROM grades of a 2 out of 5 in plantar
flexion and a 3 out of 5 in inversion, it is indicated that there is only some loss of motion
and function. Classifying the athlete with a grade 3 sprain would imply that there is a
complete tear of one or more ligaments involved and full loss of function or motion
within the ankle. Severe swelling and ecchymosis on or above the fibula, or lateral
malleolus, are also indicative of a level 2 ankle sprain which the athlete showed direct
signs of. Gross deformity should not occur with an ankle sprain, although severe swelling
can give the impression of deformity (1). Knowing that the athlete had a previous lateral
ankle sprain also helps to diagnose this pathology. This injury is very straight forward
which is typical of most ankle sprains whether they may lateral or medial. Determining
which ligament or ligaments became the direct cause for the sprain though can sometimes
be difficult to assess. Sometime these particular injuries need radiological examinations,
which were used in this case, to determine the exact ligaments involved with this

Initial Management

Immediately following the incident the athlete took part in early management techniques
which included RICE (rest, ice, compression and elevation). These techniques were
continued and participation in practice was discontinued until her visit to the physician.
After determining that the pathology was indeed an inversion ankle sprain, her
participation remained restricted and ice continued to be applied to the lateral ankle for
20 minutes every night with the foot in elevation to reduce swelling. The athlete was also
restricted from excessive weight-bearing and placed in a boot to allow for as little
movement as possible. During resting periods the athlete was instructed to complete
ROM exercises in order to maintain motion in the injured limb.


The importance of proper rehabilitation after an ankle sprain cannot be overemphasized,
especially when the debilitating consequences of decreased range of motion, persistent
pain and swelling and chronic joint instability are considered. Regardless of weight-
bearing capacity, Achilles tendon stretching should be instituted within 48 hours after the
ankle injury because of the tendency of tissues to contract following trauma (1). Ankle
joint stability is a prerequisite to the institution of functional rehabilitation, and because
grade 1 and 2 ankle sprains are considered stable, functional rehabilitation can begin
immediately (1). The athlete focused on regaining full function to her foot, toes and ankle
by engaging in ROM exercises immediately after the occurrence of her injury. Alphabet
exercises were conducted where the ankle was moved actively in multiple planes of
motion by drawing letters of the alphabet. The athlete also used her toes to pick up small
objects from the gro und and move them to another space. Once ROM increased and
swelling and pain was controlled, muscle strengthening exercises were engaged by the
use of resistance bands and other resistance equipment. Strengthening of weakened
muscles is essential to rapid recovery and important in preventing re-injury. Exercises
should focus on the conditioning of peroneal muscles because insufficient strength is this
muscle group has been associated with ankle instability and recurrent injury (1). Since
this athlete has a history of injury recurrence, this becomes especially important.

Strengthening begins with isometric exercises performed against an immovable object in
four directs of ankle movement (1). Then, resistance exercises are performed with an
emphasis on eccentric contraction. As the patient receives full weight-bearing status
without pain, proprioceptive training is initiated for the recovery of balance and postural
control (1). Balance techniques such as standing on one foot and trying to reach for the
ground were initiated during this part of the athletes rehabilitation.

A patient who will be returning to sports participation may also require additional athletic
therapy. This type of therapy tends to be sport specific. With this particular athlete, once
full ROM was gained in her ankle, dribbling techniques and agility exercises were
conducted to allow for muscle memory rehabilitation. The teams Athletic Trainer taped
the athletes ankle before any low impact drills were engaged.

Criteria for Return

Many ankle injuries will not prevent an immediate return to action, but return to play is a
case specific decision. A patient who has a stable injury should not return to play if that
injury may become unstable. It is also very important that the athlete has pain free ROM.
The athlete must then complete functional testing pain free. Examples of functional tests
include walking, jogging, figure eights and zig-zags (5). Once functional tests can be
completed and walking a specified distance is no longer limited by pain, the patient may
progress to a regimen of 50 percent walking and 50 percent jogging (1). The main issue
to focus on when determining an athletes proper time to return to play is how stable the
entire ankle is in all its aspects. The Athletic Trainer must observe the ankle making sure
it has rid itself of all ecchymosis and swelling. They must watch the athlete run and pay
close attention to any gait impairments. The Athletic Trainer should also compare the
ankle to its bilateral companion checking to see if all structures, muscles, tendon, and
ligaments match up. Once all of these items are in order and the athlete is essentially pain
free, then return to play is allowed.

Here are some other recommendations for return to play: (6)

                       Must have full ROM

                       Must have 80-90% strength in injured ankle compared to the
                       uninjured ankle

                       Strengthen the uninjured leg
                      Run in a pool, using a floating device; swimming

                      Tape the ankle if necessary

                      High-topped footwear to stabilize the ankle

                      Cleats should be outset along periphery of the shoe to provide

                      Gradual progression of functional activities that slowly increase
                      stress on ligaments

                      Full weight bearing when you can walk without a limp

                      Lunges forward, on a 45? angle, and sideways with injured and
                      uninjured leg

                      Pain-free hopping on affected side (start with hopping with both
                      legs and progress to hopping with only injured leg)–four-square
                      hopping drills

                      Step up and over, forward and sideways, on high step in pain free

                      Stand on your toes of the injured ankle for 20 seconds, and hop on
                      your toes 10 times

                      Begin stair master, treadmill, biking

                      Running can be started as soon as you can walk in a fast pace
                      without pain; initially, start jogging in a straight line, and progress
                      to running from smooth, flat surface to uneven surfaces

                      Cutting exercises: run in figure eights, cross-over walking

                      Jump rope


The majority of this case was very basic. Inversion ankle sprains are not difficult to
evaluate due to the specificity of their mechanism and the commonality of the pathology
itself. The athlete displayed all the signs and symptoms of a typical lateral ankle sprain
which made this one a "no brainer". The only issues that needed to be considered were
possible fractures to any of the lateral bony structures or to the fifth metatarsal. The
athletes recovery was also quite normal with no alternations holding her back from
continuing the rest of her season after only a few weeks. This case study helped me to
develop a better understanding of how to perform a full evaluation of any particular
injury. I learned that you must look closely when performing your observations and
analysis because some injuries may not be as straight forward as this one. Knowing the
correct mechanisms for pathologies can easily aid you in your evaluation process. With
over 15,000 lateral ankle sprains occurr ing daily in the U.S., it is very important to assess
your case correctly the first time, to save time.


               1) "American Family Physician" Management of Ankle Sprains January 1,
               2001. Nov. 2005 <>

               2) Pribut, Steven M. Q & A Resources April 30, 1998. Nov. 2005

               3) "Sports Injury Info" Ankle Anatomy 2004. Nov. 2005

               4) "The Center for Orthopedics and Sports Medicine" Ankle Sprains 1999.
               Nov. 2005 <>

               5) "The Center for Orthopedics and Sports Medicine" Anatomy and
               Biomechanics 1999. Nov. 2005

               6) Trojian, Thomas H. McKeag, Douglas B. "The Physician and Sports
               Medicine" Ankle Sprain: Expedient Assessment and Management Vol 26
               No. 10 October 98. Nov. 2005

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