Ankle Stability and Movement Coordination Impairments: Ankle Ligament Sprains

However, the reinjury rate may be greater in high-risk sports such as basketball, in which a reinjury rate of ____% was reported

73%

linicians should recognize the increased risk for developing ankle instability in patients who

(1) have an increased talar curvature, (2) are not using an external support, or (3) did not perform balance or pro- prioception exercises following an acute lateral ankle sprain

The 3 major contributors to stability of the ankle joint are

(1) osseous congruity and fit of the articular surfaces when the joints are loaded (2) static ligamentous and capsular restraints (3) surrounding musculotendinous units.

Acute Lateral Ankle Sprain: Extrinsic Risk Factors

- Athletes who did not use a lace-up ankle brace when participating in high school football or basketball had a higher incidence of ankle injuries, irrespective of previous injury - use of external supports, including both taping and bracing, reduces the incidence of ankle sprains. - High school-aged basketball and soccer players with a history of previous ankle sprain who did not partic- ipate in a balance training program were at greater risk for ankle sprain. - An increased risk of injury has been noted in ath- letes with a previous injury who did not perform a balance program261 and in those who did not participate in a general stretching program as part of their pregame warm-up. There is also an increased rate of in- jury in athletes who did not participate in a proprioceptive exercise program and in those who did not participate in neuromuscular warm-up activities - Wearing an air-cell shoe was identified as a risk factor for ankle sprain - An increased risk of ankle injury when playing II on third- and fourth-generation artificial turf was noted in the systematic review by Williams et al - Clinicians should recognize the increased risk of acute lateral ankle sprain in individuals who (1) have a history of a previous ankle sprain, (2) do not use an external support, (3) do not properly warm up with static stretching and dynamic movement before activity, (4) do not have normal ankle dorsiflexion range of motion, and (5) do not participate in a balance/proprioceptive prevention program when there is a history of a previous injury.

Acute Lateral Ankle Sprain: Intrinsic Risk Factors:

- Previous ankle sprains have been identified as a risk factor for a future sprain in the majority of prospective cohort studies - Generally, age and gender were not found to be risk factors for an ankle sprain. - it may be that age, gender, and grade of injury are interrelated. It was noted that males between the ages of 15 and 24 and females older than 30 years of age were found to have a higher incidence of ankle sprain than their respec- tive counterparts. - Studies have mostly noted height and weight not to be risk factors for an ankle sprain - poor postural control (as assessed through instrumented force plate test- ing) was generally associated with an increased risk of ankle sprain. - limited dorsiflexion was a pre- dictor for a lateral ankle sprain. - individuals with an inflexible ankle (average dor- siflexion of 34° measured in weight bearing) were 5 times more likely to suffer an ankle sprain compared to those with an average dorsiflexion range of motion of 45 - tibial varum in females20 and a mobile foot type (as measured with computerized assessment)279 were associated with ankle sprains. - Foot type (visually classified as pronated, supinated, or neutral), Q angle, and tibiofemoral angle, were NOT associated with an ankle sprain - General ligament laxity, ankle ligament laxity and functional instability were not found to be predictors of a future ankle sprain - Better cardiovascular condition as assessed through functional performance was found to be a predictor of ankle sprains in males but not females.

why is the anterior talofibular ligament hurt more often than the lateral ligaments of the ankle

- The anterior talofibular ligament demonstrates lower maximal load tolerance before failure as compared with the posterior talofibular ligament, calcaneo- fibular ligament, anterior inferior tibiofibular ligament, and deltoid ligament. - The anterior talofibular ligament has the lowest modulus of elasticity, and injury to adjacent muscles (fibularis brevis, longus, and tertius) leaves the lateral ankle somewhat unprotected dynamically

Nearly half of all ankle sprains (49.3%) occurred during athletic activity, with which sports being the most prevalent

- basketball (41.1%) - football (9.3%) - soccer (7.9%) being associated with the highest percentage of ankle sprains.

Ankle Instability: Risk Factors

- larger talar curvature, inverted heel at heel strike of gait, decreased foot clearance when walking, prolonged time to stabilize after jumping, increased postural sway, and decreased concentric ankle inversion strength as characteristics associated with ankle instability. - Based on the information presented for acute lat- eral ankle sprain, a risk for developing ankle insta- bility could include not wearing an external support or not performing balance and proprioception activities as part of an appropriate rehabilitation program following an acute lateral ankle sprain

A lateral ankle sprain consists of partial or complete disruption of the lateral ankle ligaments. These ligaments consist of the

1) anterior talofibular ligament 2) calcaneofibular ligament 3) posterior talofibular ligament Up to 73% of lateral ankle sprains involve isolated anterior talofibular ligament injuries

The ankle joint was found to account for what % of all sports related injuries and lateral ankle sprains comprise ___% of these injuries

10% to 34%; 77% to 83%

estimated the incidence rate of an ankle sprain to be

2.15 per 1000 person-years in the general population.

A systematic review noted that reinjury occurred in what % of people

3% to 34%

what percent of people still experienced pain after 3 years

5-25%

what percent of people continued to have pain at 1 year or longer follow up

5-33%

What percentage of individuals with a subjective report of full recovery approximately 3 years after the injury and seemed to be independent of sprain severity.

50% and 85%

why would an anticipatory muscle contraction be more important to protect against inversion ankle injuries than a reflexive response?

Anticipatory muscle action may increase active muscle stiffness, and hence joint stiffness, while simultaneously increasing the sensitivity of the muscle spindle to stretch.

what is the origin and insertion of the anterior talofibular ligament

Its fibers course laterally from the talus in the transverse plane and superiorly between the sagittal and frontal planes to attach on the anterior distal tip of the lateral malleolus.

does the lateral subtalar ligaments cross the ankle joint?

No! Unlike the anterior talofibu- lar ligament, calcaneofibular ligament, and posterior talo- fibular ligament, the lateral talocalcaneal ligament does not cross the ankle joint

when considering doing surgery versus non-surgery, what were the results?

Physically active males (mean age, 20.4 years) with acute grade III injuries were randomly allocated to surgical (n = 25) or functional (n = 26) treatment. Long- term follow-up (mean, 14 years) found that both groups had recovered to preinjury activity level. The prevalence of reinjury was 1 of 15 in the surgical group and 7 of 18 in the functional treatment group --> surgery appeared to decrease the prevalence of reinjury, potentially at the expense of increasing the risk of developing posttraumatic osteoarthritis

what are residual problems of an acute lateral ankle sprain

Residual problems included pain (30%), instability (20%), crepitus (18%), weakness (17%), stiffness (15%), and swelling (14%).

attachment sites of the lateral subtalar ligaments?

The fibers of the lateral talocalcaneal ligament are parallel to and blend in with the posterior fibers of the calca- neofibular ligament

attachment sites of the inferior extensor retinacula

The inferior extensor retinaculum courses from the tip of the lateral malleolus to insert on the lateral calcaneus and sinus tarsi. --> the inferior extensor retinacu- lum also blends with the inferior fibular retinaculum and may improve evertor muscle function

what were other findings associated with chronic ankle instability

The literature has noted altered al- pha motor neuron pool excitability in not only the muscles that cross the ankle but also in the proximal limb muscles.110 Decreased hip abduction and trunk strength91 and altered proximal lower extremity muscle activation patterns were also found in those with chronic ankle instability.

which 3 muscles are thought to eccentrically control ankle plantar flexion

The tibialis anterior and extensor digito- rum longus and brevis

what is a unique fxn of the lateral subtalar ligaments?

These ligaments have a large modulus of elasticity and are considered stabilizers of the subtalar joint throughout the entire range of motion.

if lateral ankle sprains commonly occur in plantar flexion, and these muscles are also thought to protect against injury, then why is the lateral ankle still so commonly injured?

both peripheral and central reactions of a muscle response are likely too slow to protect against a sudden inversion force

which joints does the calcaneofibular ligament cross

both the ankle and subtalar joints

what type of bundles can the anterior talofibular ligament have?

can have single (38%), bifurcated (50%), or trifurcated (12%) fiber bundles.

there is decreased _______ strength in those with chronic ankle instability

concentric inversion

Fxn of the extensor and fibular retinacula

contribute to ankle and hindfoot stability primarily due to their anatomi- cal orientation.

extrinsic factors (def)

describe features outside/external to the individual that may put an individual at risk for lateral ankle sprain, and generally in- clude the use of external support, sport, level of competition, and participation in neuromuscular training.

intrinsic factors (def)

describe the char- acteristic of an individual that increases their risk for a lateral ankle sprain and include the history of previous sprains, age, gender, physical characteristics (ie, height, weight, and body mass index), and musculoskeletal characteristics (ie, bal- ance, proprioception, range of motion, strength, anatomic alignment, and ligament laxity)

functional ankle instability (def)

describes those who report instability but seem to have normal joint motion --> it has been hypothesized that func- tional ankle instability results from sensorimotor and/or neu- romuscular deficits

Decreased ankle ______ strength, noted shortly after injury, seems to resolve over time.

eversion

Is the anterior talofibular ligament an extra or intra articular ligament

extra-articular ligament of the talocrural joint

The most common mechanism of injury occurs with

forefoot adduction, hind- foot internal rotation, ankle inversion in plantar flexion, and external rotation of the leg beyond anatomical constraints.

Prognosis:

having a high level of activity, defined as training 3 times or more per week, increased the likelihood for residual symptoms --> Prognosis may also be related to not receiving appropriate treatment after injury, including bracing and rehabilitation

is the posterior talofibular ligament an extra or intra articular ligament

intracapsular but extrasynovial

Risk factors for acute lateral ankle sprain are categorized as being

intrinsic or extrinsic

what motions injure the lateral subtalar ligaments?

inversion injuries

The lateral ligaments of the ankle complex are potentially injured with what type of movement

inversion or supination

Is the calcaneo-fibular ligament an extra or intra articular ligament

is an extra-articular ligament of the talocrural joint

why would a patient get early onset of posttraumatic ankle arthritis?

is there is chondral damage + repetitive ankle sprains

what is the fxn of the posterior talofibular ligament

it is the strongest of the lateral ligaments222 and primarily functions to provide transverse plane rotatory stability

what nerves are effected after a lateral ankle sprain

joint receptors and cutaneous nerves, such as the sural nerve and distal superficial peroneal nerve

Age and genders of those effected by ankle sprains

males between 14 and 24 years of age and females older than 30 years of age

Individuals with long-term symptoms and signs after acute lateral ankle injuries are commonly characterized as either having

mechanical or functional ankle instability

what motions may cause injury to the ligament

movements that in- volve extreme ankle dorsiflexion, foot external rotation and pronation, along with limb internal rotation

aside from local musculature, a lateral ankle sprain effects what PROXIMAL muscles?

muscle weakness of the bilateral gluteus maximus, biceps femoris, and lumbar erector spinae --> Abnormal hip muscle activation has been found after ankle inversion movements in those with ankle hypermobil- ity after injury.

sensorimotor deficits associated with ligamentous disruption in individu- als with lateral ankle sprains include:

proprioception, postural control, reflex reactions to inversion perturbation, alpha motor neuron pool excitability, and muscle strength

attachment sites of the superior fibular retinacula

runs from the lateral malleolus to the calcaneus, parallel with the posterior fibers of the calcaneofibular ligament.

what are the attachment sites of the posterior talofibular ligament?

runs from the posterior- medial portion of the fibula to the lateral tubercle on the posterior aspect of the talus.

because the calcaneofibular ligament crosses the subtalar joint and parallels its axis, motions of what other joint effect it?

subtalar joint motions

what is the origin and insertion of the calcaneofibular ligament

that courses from the anterior distal tip of the fibula obliquely downward and backward to the lateral calcaneus.

The hindfoot is composed of

the distal tibiofibular syndesmosis, talocrural joint, and subtalar joint

The anterior talofibular ligament restricts

the primary restraint to inversion movement when the ankle is in a plantar-flexed position --> Damage to the ligaments is dependent on the ankle and foot position at the time of injury and the velocity of the mechanism of injury.

mechanical ankle instability (def)

used to describe those who have excessive joint motion --> those with mechanical ankle instability may not only have laxity in the talocrural joint but also the subtalar joint, with both contributing to symptoms of instability

what are common complaints of people in subacute phase of healing after an acute lateral ankle sprain

xperience weakness, impaired balance response, stiffness, swelling, decreased function, and instability.