Conditions of the Hip, Foot, and Ankle Flashcards
What is developmental dysplasia of the hip (DDH)? How common is it?
- (previously called congenital dislocation of the hip)
- patients are born with dislocation or subluxation of the hip (femoral head is displaced from the acetabulum)
- occurs in 1 in 1,000 live births; more common in females; left side is more commonly affected (60%, right is 20%, bilateral is 20%)
What is developmental dysplasia of the hip (DDH)? How common is it?
- (previously called congenital dislocation of the hip)
- patients are born with dislocation or subluxation of the hip (femoral head is displaced from the acetabulum)
- occurs in 1 in 1,000 live births; more common in females; left side is more commonly affected (60%, right is 20%, bilateral is 20%)
When is the risk for developmental dysplasia of the hip (DDH) greatest?
- risk is present at 4 times: 12th week, 18th week, final 4 weeks, and the post natal period
- (DDH increases dislocation probability after birth in the last category)
What is Trendelenburg’s sign/gait?
- single stance
- a gait/stance abnormality due to a shift in the center of gravity
- patient lurches towards the affected (weaker) side and the contralateral (normal) hemi-pelvis drops below the normal horizontal
- (affected hemi-pelvis and hemi-buttocks are tilted and elevated in contrast)
What is Barlow’s test? Ortolani’s test?
- Barlow’s positive: femoral head is dislocated when flexed hip is adducted towards midline and pushing down
- Ortolani’s positive: reverse of Barlow’s to reduce the dislocated hip (an audible clunk is heard)
Developmental dysplasia of the hip (DDH) is characterized by which findings on X-ray?
- small, delayed ossification center
- acetabular slope
- displacement of the femoral head
- a break in Shenton’s line (this line should be smooth and continuous from the femoral head to the pubic symphysis)
What is Legg-Calve-Perthes disease? How do patients present?
- avascular necrosis of the femoral head in children, possibly due to repeated micro trauma
- more common in males
- patients present with recurrent episodes of hip pain and limp
- younger patients have better prognoses
- these patients have an increased risk of developing early osteoarthritis
What is Trendelenburg’s sign/gait?
- single stance
- a gait/stance abnormality due to a shift in the center of gravity
- patient lurches towards the affected (weaker) side and the contralateral (normal) hemi-pelvis drops below the normal horizontal
- (affected hemi-pelvis and hemi-buttocks are tilted and elevated in contrast)
What is Barlow’s test? Ortolani’s test?
- Barlow’s positive: femoral head is dislocated when flexed hip is adducted towards midline and pushing down
- Ortolani’s positive: reverse of Barlow’s to reduce the dislocated hip (an audible clunk is heard)
Developmental dysplasia of the hip (DDH) is characterized by which findings on X-ray?
- small, delayed ossification center
- acetabular slope
- displacement of the femoral head
- a break in Shenton’s line (this line should be smooth and continuous from the femoral head to the pubic symphysis)
What is Legg-Calve-Perthes disease? How do patients present?
- avascular necrosis of the femoral head in children, possibly due to repeated micro trauma
- more common in males
- patients present with recurrent episodes of hip pain and limp
- these patients have an increased risk of developing early osteoarthritis
How do we treat a fractured femur neck?
- minimize best rest and maximize mobility
- only perform operation in high-risk patients (hemiarthroplasty or ORIF: open reduction internal fixation)
Sudden explosive contraction or over stretching results in which type of fracture of the hip? Where are the three most common sites?
- avulsion fracture
- ASIS, superior iliac crest, ischial tuberosity
What causes hip dislocations? Are posterior or anterior dislocations more common?
- mainly caused by high energy trauma (ie, in sports)
- 85% are posterior (results from an axial load to the femur with the hip flexed)
- anterior dislocations are caused by forced abduction with external rotation
What causes femur neck fractures in young patients? In elderly patients? What is the prognosis in elderly patients?
- young: high energy trauma (ie, sports)
- elderly: osteoporosis; 25% die within the 1st year, 25% will require residential care; 50% will not regain mobility
How do we treat a fractured femur neck?
- minimize best rest and maximize mobility
- only perform operation in high-risk patients (hemiarthroplasty or ORIF: open reduction internal fixation)
What is the most common lower limb injury? Who does it usually occur in? Which two structures are usually involved? What’s the prognosis?
- lateral ankle sprains
- usually in young, active people
- tears in either the anterior talofibular ligament (ATFL) if ankle is plantarflexed and/or the calcaneofibular ligament (CFL) if ankle is dorsiflexed; these (along with the posterior talofibular) are the lateral collateral ligaments
- 95% have a good recovery
- (the CFL is the strongest lateral ligament)
- (anterior draw test will test laxity of ATFL)
What is the most common mechanism of lateral ankle sprains? What are the anatomic and histologic classifications for ankle sprains? The clinical classification?
- inversion stress with plantarflexion (so anterior talofibular ligament is usually involved)
- anatomic: I (ATFL), II (ATFL and CFL), III (complete ligamentous disruption)
- histo: I (stretching), II (partial tearing), III (complete rupture)
- clinical: I (normal stress tests; lateral tenderness), II (pain and swelling, stress tests can be pos or neg; medial + lateral tenderness), III (severe pain and swelling, positive stress tests; bruising + swelling)
What imaging do we use for ankle sprains?
- x-ray only if indicated via the Ottawa ankle rules
- (US and MRI are wastes of time and money)
What is Achilles tendinopathy?
- a chronic, degenerative disorder of the Achilles tendon
- usually occurs in elderly patients
What is syndesmosis?
- “high ankle sprain”; spraining of the joints between the tibia and fibula (tibiofibular ligaments, interosseous membrane)
- leads to instability (especially if a fracture is involved)
What percentage of ankle sprains are medial? What’s the mechanism of injury? What are they associated with?
- 5% of ankle sprains
- due to forced eversion and external rotation
- injures the deltoid ligament
- associated with syndesmosis and proximal fibular fractures
Which patients usually experience Achilles ruptures? How do patients present? Where does the rupture occur?
- usually occurs in middle-aged recreational athletes
- you’ll hear a loud whip-like snap upon rupture, followed by acute pain when contracting; calf squeeze test is positive
- you CAN still walk with an Achilles rupture
- rupture occurs 2-6 cm above the Achilles insertion (a watershed area)
What is Achilles tendinopathy?
- a chronic, degenerative disorder of the Achilles tendon
- usually occurs in elderly patients
In patients with plantar fascitis, 99% will settle/recover within what time frame?
- 12 to 18 MONTHS
- note that plantar fascitis is very common
What is pes planus? What causes it? Which populations are at risk?
- pes planus is adult acquired flat foot due to dysfunction of the posterior tibial tendon
- patient is unable to perform a single heel raise
- middle-aged, obese females are at greatest risk
Lisfranc Injuries; Fleck Sign
- Lisfranc ligament is between the medial cuneiform and 2nd metatarsal
- patients classically present with an icepack on the FOOT (not the ankle) and bruising on the plantar surface
- Fleck sign (malalignment of metatarsals and cuneiform) on weight-bearing x-ray indicates instability
How do we treat osteoarthritis of the ankle?
- arthrodesis (fuse the bones together; this will decrease ROM but solve the issue and alleviate the pain)
- joint replacements are fairly good, but will inevitably wear out and fail
How do we treat ankle sprains?
- 3 phases:
- phase 1: limit extent of injury; RICE (rest, ice, compression, elevation), limit weight-bearing, NSAIDs
- phase 2 (once pain and edema are relieved): restore ROM and strength; resistance training
- phase 3 (once strength is about 90% returned): restore agility; gradual increase in activity
What should we do for patients with an ankle sprain that don’t improve in 6-10 weeks time?
- occurs in 5-10% of cases
- do an MRI or CT scan
- suspect underlying pathology: missed fracture, syndesmosis, osteochondral lesions, peroneal tendinopathy, sinus tarsi syndrome
