Transcript Mohamed Akl

 Impingement is a painful mechanical limitation of full ankle
movement secondary to osseous or soft tissue abnormality.
 The prevalence and incidence rates are high. Impingement
complicates 3% of all ankle sprains, and with incidence rate in
athletes reaching 16%.
 Ankle impingement was first described by Morris, (1943) as a
common cause of ankle pain in athletic patients who undergo
repetitive forced dorsiflexion or plantar flexion of the ankle.
 The ankle joint is approximately a uniaxial hinge. The lower
end of the tibia and its medial malleolus, the lateral malleolus
and the transverse tibiofibular ligament, form a deep recess
('Mortise') for the body of the talus.
 Dorsiflexion is to 10º with the knee straight, and to 30º with
knee flexion and planter flexion is to 30º.
Bony anatomy of ankle joint formed by:
Tibial plafond.
Medial Malleolus.
Lateral malleolus.
Talus.
Ankle ligaments:
A. Lateral collateral ligament (LCL):
 Anterior talo-fibular ligament (ATFL)
 Calcaneofibular ligament (CFL)
 Posterior talo-fibular ligament (PTFL)
B. Medial collateral ligament (MCL) “Deltoid ligament”:
 Superficial Layer:

Tibionavicular ligament

Tibiospring ligament

Superficial tibiotalar ligament

Tibiocalcaneal ligament
 Deep Layer:

Deep posterior tibiotalar ligament

Deep anterior tibiotalar ligament
C. Syndesmosis:
 Anteroinferior tibio-fibular ligament.
 Posteroinferior tibio-fibular ligament.
 Interosseous tibio-fibular ligament.
 Bony stabilizers:
 They contribute approximately 30% of the resistance to rotational
forces around the ankle, with the remainder attributed to the soft
tissues.
 The trapezoidal shape of the talus, wide anteriorly and narrow
posteriorly, provides strong bony constraint to the tibio-talar joint in
neutral flexion and dorsiflexion.
 Ligamentous stabilizers:
 The lateral collateral ligament.
 The Medial collateral ligament (Deltoid ligament).
 Additional important stabilizers of the sub-talar joint are the
interosseous ligament, cervical ligament and the lateral root of
the inferior extensor retinaculum.
• In the plantarflexed position the ATFL acts as the “sole”
stabilizer, placing it at the most risk for inversion injury.
Anatomy of the major ligamentous stabilizers of the lateral ankle.
Ankle Impingement
Anterior Ankle Impingement
Bony
Soft tissue
Posterior Ankle Impingement
Bony
Soft tissue
Etiology of anterior ankle impingement:
 Traction theory: traction to the anterior ankle capsule during plantarflexion
movements results in the formation of anterior tibiotalar osteophytes.
 Bone formation is considered to be a response of the skeletal system to
intermittent stress and injury, as evidenced by Wolff's law of bone
remodeling.
 Anterolateral impingement is thought to develop subsequent to a relatively
minor injury usually consisting of forced ankle plantar flexion and supination.
 Bassett et al., (1990), were the first who reported a ligamentous etiology of
anterior ankle impingement. The distal part of the AITFL fascicle rubs against
the talus, and this causes pain at the ankle.
 Anteromedial impingement lesions are associated with both eversion and
inversion ankle injuries and also may occur following medial malleolar or talar
fractures.
 It results from injury to the deltoid ligament complex leading to scar formation
and synovitis along the anteromedial joint line.
Etiology of posterior ankle impingement:
 Posterior ankle impingement can be caused by trauma or overuse as in ballet
dancers and runners.
 An anatomic variation such as an os trigonum is often associated with this
entity.
 Between 8 and 11 years of age, a separate ossification center appears posterior
to the posterior process of talus.

When the ossification center doesn't fuse to the lateral tubercle, the ossicle
is named the “Os trigonum”.

When it is fused to the posterior process, it becomes an elongated posterior
process. "Trigonal process" or "Stieda's process" .

The articular surface of the posterior tibia and the calcaneal tuberosity are
also involved in the impingement mechanism.
Diagram demonstrating variations in posterior ankle anatomy that contribute to
posterior ankle impingement syndrome. 1.Stieda's process; 2.Os trigonum;
3.Fractured lateral tubercle of talus; 4.Downward sloping posterior tibial plafond;
5.Calcified inflammatory tissue; 6.Prominent superior surface of calcaneal tuberosity.
Pathology of anterior ankle impingement:
 Bony anterior ankle impingement:

Osteophytosis is the process of formation of new bony spurs at the
joint margin causing protrusions around the joint space.

Once the osteophytic prominence forms, impingement occurs more
easily. So that, the impingement spur once formed often increase in
size and eventually may break off forming a loose body.
•
Scranton and McDermott in 2000, advised a classification system that
aide in both clinical and operative decision making:
I. Grade 1: Synovial impingement & inflammation. Tibial spurs > 3mm.
II. Grade 2: Grade 1 with tibial spurs < 3 mm. No talus spurs.
III. Grade 3: Grade 2 with spurs on the talus.
IV. Grade 4: Tibial and talar spurs with pantalocural arthritis.
 Soft tissue anterior ankle impingement:
• A localized soft tissue reaction can occur after an ankle sprain with a
localized synovial or hyalinized fibrocartilaginous scar reaction.
• Chronic impingement can results in further hypertrophic synovium or
fibrocartilage formation.
• Histological examination of the meniscoid lesion showed hyalinized
and fibrous stroma partially covered by synovial membrane with
blood vessels, but no ligamentous structures were found.
Pathology of posterior ankle impingement:
 Soft tissue posteromedial impingement lesion is usually caused by entrapment
of fibrotic scar tissue in the medial ankle gutter and posterior aspect of the
medial malleolus.
 Osteophytes of the posterior tibial rim, an os trigonum, and even part of the
posterior talar process may break off during a hyper-plantarflexion trauma
and act as a loose body.
 After a severe inversion trauma, the posterior talofibular ligament may
avulse a bony fragment from posterior talar process and may cause posterior
ankle impingement.
Diagnosis of anterior ankle impingement:
 Clinical diagnosis:
• Occurs more commonly in active people and athletes probably
because recurrent sub- clinical injury.

Symptoms: Patients present with pain, stiffness, swelling and
subjective feeling of blocking on dorsiflexion. Symptoms are
exacerbated by activity and may radiate to the lateral or medial
malleolus.
 Signs: Molloy et al., (2003), described a physical sign for diagnosis
synovial anterolateral impingement.
Photographs showing a) plantar flexion of the ankle with thumb pressure over the
anterolateral aspect, b) dorsiflexion of the ankle with no thumb pressure over the
anterolateral aspect and c) the combined maneuver by thumb pressure and dorsiflexion.
 If the combined maneuver produces pain or intensifies the pain
already felt with pressure alone in the plantar flexed position, this is
considered to be a positive sign.

Syndesmotic ankle impingement is diagnosed by positive squeeze test
and external rotation test.
Squeeze test.
External rotation test.
 Radilological diagnosis:
 X-Ray:
• Bony ridge may be seen extending forward from the surface of the
tibia. Occasionally, a similar bony outgrowth is seen projecting
upward and slightly backward form the neck of the talus.
 CT :
• CT is helpful in localizing the osteophyte and planning the
operative approach. 3D CT is an excellent tool investigating the
morphology, location, shape, size and number of the osteophytes
preoperatively.
 Ultrasound :
• Ultrasound assessment show nodular, mixed echogenic synovial
mass within the anterolateral recess.
• Importantly, findings of U/S are not dependent on the presence of
an ankle joint effusion, unlike MR imaging.
 MRI :
• MR imaging accurately detects and localizes anterior tibiotalar
spurs, adjacent reactive synovitis and fibrosis, subchondral marrow
edema , collateral ligament complex injury, osteochondral lesions
and intra- articular bodies.
sagittal T1-weighted, demonstrating anterior tibial and talar osteophytes,
sagittal proton density T2 with fat suppression show bone marrow edema, besides anterior
capsular thickening characterizing anterior ankle impingement.
Diagnosis of posterior ankle impingement:
 Clinical diagnosis:
• It occurs usually in ballet dancers as well as individuals who are active in
sports as soccer, basketball, running, and volleyball players.
• Symptoms: The patient complains pricking posterior ankle pain during
push off while running. The pain is often absent during walking on level
ground. Plantarflexion may be limited and painful.
• Signs: Physical examination can reveals the presence of moderate swelling
on the medial or on both sides of the Achilles tendon, with tenderness on
palpation.
 Posterior impingement test : repetitive quick
hyper-plantarflexion movements in
passive
a patient
sitting with the knee flexed at 90o,
with slight
external rotation or internal rotation
of the foot
on the tibia, which cause grinding
the posterior
talar process/os trigonum between
tibia and
calcaneus, which intensifies the pain.
 Diagnostic infiltration test: the pain disappears on forced plantar
flexion after local infiltration of xylocain is diagnostic for posterior
ankle impingement.
 Radilological diagnosis:
 X-Ray:
 Is the first step in the assessment of all cases of posterior ankle
impingement.
 Os trigonum is usually triangular.
 Acute fracture of the posterior process or Stieda’s process will
appear as an irregular and rough fracture line.
 Bone scan:
 Bone scan is positive in an acute fracture of the posterior process
and in symptomatic os trigonum.
 Ultrasound:
 Hypoechoic nodular, soft tissue thickening deep to tibialis
posterior, between the medial malleolus and talus involving the
posterior tibiotalar ligament.
 Also can identify capsular abnormality.
Nonsurgical injection treatment of soccer player with clinical posterior
impingement. Axial ultrasound shows nodular hypoechoic synovitis (*), os
trigonum (Os), talus, and needle placement (arrow).
 CT :
• CT scan is best suited to make the distinction between
intraarticular
abnormalities
versus
an
extra-articular
intracapsular.
Sagittal (A) and axial (B) CT image of the ankle in long-standing os trigonum.
or
 MRI :
• Common soft tissue abnormalities include posterior capsular
thickening, a fluid-distended posterior joint space and increased T2
weighted signal along the posterior margin of the ankle are
indicative of synovitis and FHL tenosynovitis .
Sagittal T2 shows posterolateral capsular
synovitis and thickening.
Sagittal T2 showing marked inflammation in
the flexor hallucis longus (FHL) sheath
(arrow) in a professional ballerina.
Conservative treatment:
• In the form of ankle braces, physical therapy, non-steroidal antiinflammatory drugs and one or more injections of local anaesthetic
and/or steroid into the posterior ankle to treat the impingement
symptoms which may be successful.
Surgical treatment of anterior ankle impingement:
Open spur resection and debridement:
• Severe tibio-talar spurs in grade IV lesions (Scranton’s grading)
should be considered for arthrotomy.
• the resection should be restricted mainly to the tibial spurs in order
to prevent osteonecrosis of the talar neck.
• skin incision just lateral to the anterior-most fibers of the deltoid
ligament, proximal extent to the level of the tibio-talar articulation
and the distal extent should reach the region of the talar neck.
Arthroscopic treatment:
• Anterior ankle arthroscopy is both diagnostic
and therapeutic for many ankle disorders.
• Ankle arthroscopy can be performed with
without distraction device.
• Standard anteromedial and anterolateral
ankle arthroscopy portals are utilized.
or
• Guhl technique: James F.Guhl et. al.,
prefer supine position with the thigh
supported by a thigh holder and
non-invasive distraction is applied.
• Van Dijk technique : Patient is in supine
position without distraction with the ankle
in the fully dorsiflexed position.
Surgical treatment of posterior ankle impingement:
Open surgery:
• Historically, it can be performed through a lateral or medial
approach. But the complication rates reported were rather high.
• The most commonly recommended approaches in open operative
treatment are posterolateral, posteromedial, or combined approach.
 Arthroscopic treatment:
• Marumota and Ferkel technique:
Place the patient supine with a thigh support
and utilize standard anterolateral and
posterolateral portals to access the subtalar joints.
• Lombardi et al., technique: Place the patient
in the lateral decubitus position and describe
the use of two "stacked" posterolateral portals
to access and excise the os trigonum.
• Van Dijk technique: patient placed in a prone position with access
via both posterolateral and posteromedial portals.
• Rehabilitation of ankle arthroscopy:
• Immobilization in a posterior splint and the patient is non–weight
bearing immediately after surgery for 10 days then gradual weight
bearing as tolerated in boot walker.
• After 2 weeks postoperatively, patients are weaned from the boot
and can start working with a physical therapist on progressive
ankle strengthening, ROM and gait training.
• Advantages of arthroscopic surgery over open surgery in
treatment of ankle impingement:

Direct visualization of structures.

Improved assessment of articular cartilage.

Less post-operative morbidity.

Faster as well as functional rehabilitation, earlier resumption
of sports.
• Complications of ankle arthroscopy:
• Ankle portals are in close proximity to neurovascular structures
that can be easily damaged.
The anterolateral portal should avoid the terminal branches of
the superficial peroneal nerve and FHL.
The anteromedial portal should avoid the saphenous vein and
nerve.
• The infection rate after arthroscopic surgery of the ankle is
approximately 0.1%, which is similar to most of other joints.
• Damage to the articular cartilage, loose bodies and debris created
during the resection, sinus tract formation, and fluid extravasation
are other possible complications.
• Ankle impingement is a frequent ankle morbidity that has higher
incidence and prevalence rates among a highly demanding group
(athletes and dancers).
• Once the diagnosis of impingement is confirmed by clinical and
radiological evaluation, usually there is a little improvement with
nonsurgical treatment.
• Arthroscopy has proved to provide better functional and overall
results compared with open techniques.
• Most of the existing literature promotes the use of ankle
arthroscopy to surgically treat ankle impingement.