Ankle sprain
An ankle sprain is a common musculoskeletal injury that involves the stretch or tear (partial or complete) of the ligaments of the ankle.
LATERAL COMPARTMENT
LIGAMENT SPRAINS
Epidemiology
This ligament is the most frequently injured structure in sports (25% of all sports injuries) where
running and jumping are important, particularly
basketball, volleyball, football, soccer,field hockey, and racquetball.
The incidence rate
is 1.6 (male) and 2.2 (female) significant sprains
per 1000 person-days of sports.
Risk factors include -
tibial varum and calcaneal eversion in females and
increased talar tilt in males.
For both genders, a history of ankle injury increases the risk of repeat trauma
shoes with air cells in the heel
lack of stretching
Mechanism of Injury
Inversion, plantar flexion, and adduction (supination) especially during landing.
Anatomy
Sequential tearing of anterior talofibular (ATF),calcaneofibular (CF), and posterior talofibular(PTF) ligaments.
grade
1 (<30%of fibers torn)
2 (30–70% of fibers torn)
3 (>70% of fibers torn).
Symptoms
Grade 1 — minimal pain and disability;
weight bearing not impaired
Grade 2 — moderate pain and disability;
weight bearing difficult
Grade 3 — severe swelling, pain, discoloration; no weight bearing possible; significant functional loss
Signs
Grade 1
slight tenderness and swelling over ligament with no laxity
anterior drawer test and talar tilt negative
Grade 2
moderate tenderness and edema; hemarthrosis, ecchymosis,
positive talar tilt (5 to 10° difference),
positive anterior drawer (4 to 14 mm).
Grade 3
pronounced edema and loss of function, typically with severe pain but
may be painless; hemarthrosis,, ecchymosis.
positive talar tilt (>10° difference).
anterior drawer (>15 mm).
X-Rays
Anteroposterior, lateral, and mortise views may show localized tissue swelling,
lateral clear space >2 mm.
Special Studies
Interpretation of stress films may be difficult, and a mechanical stress
device is recommended.
Grade 1 — negative
Grade 2 — 5 to 10° tilt difference; 3- to
14-mm anterior displacement of talus.
Grade 3 — >20° tilt difference; >15-mm
anterior displacement of talus.
An arthrogram has the advantages of being able to
identify calcaneofibular tears and extravasation of
dye with calcaneofibular tears. MRI provides direct
visualization of the ATF and CF ligaments in acute
and chronic injuries; 27% show bone contusions.
Diagnosis
Lateral compartment sprain grade 1, 2, or 3.
Differential Diagnosis
Posterior compartment osteochondral fracture,
peroneal tendon subluxation/dislocation
peroneal quartus strain,
physical injury of the distal fibula in skeletally immature patients
interosseous membrane tear,
tibiofibular ligament sprain,
Achilles tendon rupture,
subtalar and Lisfranc joint sprain,
avulsion fracture of fibula or break of os calcis.
Treatment-
A. Initially:
Treat with RICE,
posterior plaster or air splint,
no weight bearing;
NSAIDs and analgesics as needed.
Homeopathic ointment for 10 days has been found to significantly improve
pain control vs. placebo.
Grade 1 — Weight-bearing brace or
strapping for 2 to 3 weeks.
Grade 2 — Walking, well-padded dorsiflexion cast, Unna boot weight-bearing brace or air-stirrup for 2 to 4 weeks, followed by strapping at 90° for 2 to 4 weeks. Avoid casting severely swollen limbs.
Grade 3 — Dorsiflexion cast or weight bearing brace for 3 to 6 weeks, followed by orthotic or strapping for 3 to
6 weeks; surgical repair. Best approach
is unresolved, although age <40 and
athletic competition favor surgical
repair.
Rehabilitation should include isometrics while the cast is on, then range of motion (ROM), progressive resistance exercise (PRE), and proprioceptive
exercises (balance/wobble board), plus functional activity:
Injection therapy can be used in a stable ankle that is chronically inflamed, preventing progression in a rehabilitative program.
Ultrasound and cold packs have been found to offer no significant benefit over placebo, and the benefit for Diathermy over sham therapy is conflicting.
Complications
Recurrent sprains
osteochondral fracture instability
peroneal and/or tibial nerve injury,
peroneal tendon subluxation/dislocation.
Prevention
Peroneal muscle conditioning program;
teaching players to land with a relatively wide-based stance;
support with tape or an orthosis (semirigid
or air-cast) for previously injured ankles,
particularly in high-risk sporting activities such as basketball or soccer brace/stabilizer perhaps being superior to taping;
use of an outer heel wedge;
coordination training on balance board;
wearing high-top, flexible
shoes with cushioned midsoles
adequate toe box.
MEDIAL COMPARTMENT
LIGAMENT SPRAINS
Epidemiology
Of all ankle sprains, 5 to 10% involve the medial compartment
this is a more serious injury than a lateral sprain.
Mechanism of Injury
Eversion, dorsiflexion, and abduction (pronation).
Anatomy
Sequential tearing of the superficial deltoid ligament (tibionavicular), anteromedial capsule, anterior deep deltoid component, anterior tibiofibular
ligaments, interosseous membrane, and remaining
superficial and deep components.
Symptoms
Grade 1 — minimal pain and disability;
weight bearing not impaired
Grade 2 — moderate pain and disability;
weight bearing difficult
Grade 3 — severe swelling, pain, discoloration; no weight bearing possible; significant functional loss
Signs
Grade 1
slight tenderness and swelling over ligament with no laxity
anterior drawer test and talar tilt negative
Grade 2
moderate tenderness and edema; hemarthrosis, ecchymosis,
positive talar tilt (5 to 10° difference),
positive anterior drawer (4 to 14 mm).
Grade 3
pronounced edema and loss of function, typically with severe pain but
may be painless; hemarthrosis,, ecchymosis.
positive talar tilt (>10° difference).
anterior drawer (>15 mm).
X-Rays
Anteroposterior, lateral, and mortise views may show localized tissue swelling,
lateral clear space >2 mm.
Special Studies
Stress films show increased talar tilt on eversion
stress; arthrography shows extravasation of dye;
MRI is positive.
Diagnosis
Medial compartment sprain grade 1, 2, or 3
.
Differential Diagnosis
Avulsion fracture of medial malleolus (15%),
sprain of anterior tibiofibular ligament and
interosseous membranes,
osteochondral fracture,
strain of the tibialis posterior,
Tillaux fracture.
Treatment
A. Initially-
RICE,
posterior splint,
non weight bearing,
NSAIDs, analgesics as needed.
B. Long-term:
Grade 1
weight-bearing
cast for 2 to 3 weeks, followed by
brace/strapping; grades 2 and 3 —
weight-bearing cast for 5 to 6 weeks,
followed by brace/strapping. Operative repair, as necessary. For rehabilitation, see discussion in Lateral
Compartment Ligament Sprains section, above.
Consultation: see lateral ankle sprains
Complications
Chronic ankle instability
recurrent sprains.
Prevention
Strengthening of posteromedial muscles;
taping/strapping/bracing (an ankle brace/stabilizer
may be superior to taping);
inner heel wedge;
balance board training.