Conditions Of The Hip Flashcards
What is at risk when administrating IM injections in the gluteal region? 1️⃣
Injury to the sciatic nerve
When is the dorsogluteal site used? 1️⃣
In children 3-7
When is the ventrogluteal site used? 1️⃣
Children >7 and adults
Site is further from neurovascular structures but requires better patient compliance
How is the ventrogluteal site located? 1️⃣
- place palm over greater trochanter
- point thumb towards inguinal region
- point index finger toward anterior superior Iliad crest
- spread index and middle fingers to make a V
- inject between the proximal interphalangeal joints of the fingers, into the gluteus medius
What does a superior gluteal nerve lesion lead to? 2️⃣
Superior gluteal nerve supplies hip abductors therefore lesion leads to weakness in thigh abduction at the hip
How can the superior gluteal nerve be injured? 2️⃣
- complication of hip surgery
- injections into buttock
- # of greater trochanter (insertion site of gluteus medius)
- hip joint dislocation
What prevents hip tilting when standing on one leg? 2️⃣
Standing erect with one foot lifted off ground:
- gluteus medius and minimus is supporting limb usually contract
- prevents tilting of pelvis towards unsupported side
Describe a postitive Trendelenburg sign 2️⃣
Person with superior gluteal nerve palsy asked to stand on injured lower limb:
-pelvis on unsupported side descends
When does a hamstring injury tend to occur (‘pulled hamstrings’) 3️⃣
During sudden muscular exertion that results in stretching of the posterior thigh muscles :
- jumping
- sprinting
- lunging
Relatively common in athletes and footballers esp in absence of a proper warm up
What occurs in a hamstring injury? 3️⃣
- sudden tension in hamstrings results in either a muscle sprain, partial tear or a complete tear of the origin of the hamstrings from the ischial tuberosity
- sometimes accompanied by avulsion of a fragment of bone
What is the pathological definition of osteoarthritis? 4️⃣
A degenerative disorder arising from the breakdown of articulate hyaline cartilage
What is the clinical definition of osteoarthritis? 4️⃣
A clinical syndrome comprising joint pain accompanied by functional limitation and reduced QoL
What joints are most commonly affected by OA? 4️⃣
- hips
- knees
- cervical spine
- lumbar spine
- small joints of the hands
Describe the features of OA 4️⃣
- chronic disease of musculoskeletal system
- without systemic involvement
- non-inflammatory
- in comparison to some other inflammatory arthropathies, ankylosis (bone fusion across a joint) is very rarely seen
Difference between primary and secondary OA 4️⃣
Primary OA: unknown cause
Secondary OA: known precipitation cause
What are some risk factors for primary OA? 4️⃣
- age
- female sex
- ethnicity (increased in African-Americans, American Indians and Hispanics)
- Genetics (OA) runs in family
- Nutrition (consumption of antioxidant-rich diet may provide some protection)
Give examples of specific causes of secondary OA 4️⃣
- obesity
- trauma
- malalignment
- infection e.g septic arthritis and tuberculosis
- inflammatory arthritis e.g RA
- metabolic disorders affecting joints e.g gout
- haematological disorders e.g haemophilia with haemarthrosis
- endocrine abnormalities e.g diabetes with neurovascular impairment leading to chronic malalignment of articular surfaces
State some symptoms of OA 4️⃣
- deep aching joint pain, exacerbated by use
- reduced range of motion and crepitus
- stiffness during rest i.e morning stiffness
What do precipitating risk factors of OA cause? 4️⃣
Lead to excessive or uneven loading of the joint
Leads to damage to the hyaline cartilage covering articular surface
Describe what happens to hyaline cartilage in OA 4️⃣
- initially becomes swollen due to increased proteoglycan synthesis by chondrocytes with increased numbers of chondrocytes differentiating from chondroprogenitor cells
- this stage reflects an attempt to repair the cartilage damage and can continue for several years
Describe what happens to the hyaline cartilage as the disease progresses 4️⃣
- proteoglycan content falls
- causes cartilage to soften and lose elasticity
- microscopically, flaking and fibrillation develop along the normally smooth articular surface
- over time, the cartilage becomes eroded down to the subchondral bone, resulting in loss of joint space
What does the surface changes in hyaline cartilage cause? (Eburnation)4️⃣
- alters the distribution of biomechanical forces and trigger further active changes in the tissues
- subchondral bone responds with vascular invasion and increased cellularity, becoming thickened and denser at areas of pressure
= eburnation - manifests as subchondral sclerosis on x rays
What else happens to the traumatised subchondral bone in OA? 4️⃣
May undergo cystic degeneration to form subchondral bone cysts
Attributable to either issues necrosis secondary to chronic impaction or to the intrusion of synovial fluid
How do the osteophytes form? 4️⃣
At areas along the articular margin, osseous metaplasia of connective tissue occurs, leading to irregular outgrowth of new bone
State 4 cardinal signs of OA in x rays 4️⃣
- reduced joint space
- osteophytes
- bone cysts
- subchondral sclerosis
Who is OA of the hip most common in? 5️⃣
Males over 40 years old
Describe the symptoms of hip OA 5️⃣
- joint stiffness
- pain in hip, gluteal and groin regions radiating to the knee via obturator nerve
- mechanical pain
- crepitus
- reduced mobility
What does treatment of hip OA involve? 5️⃣
- weight reduction if patient overweight or obese
- activity modification
- walking stick or walking frame
- muscles strengthening exercises
- orthotic footwear to rebalance misaligned load through the joint
- Analgesia and anti-inflammatories
- nutritional supplements
- steroid injections into joint to reduce swelling and alleviate stiffness and pain
- hyaluronic acid injections into joint (viscosupplementation) may increase lubrication and possible promote cartilage repair
What is the only cure for hip OA? 5️⃣
Total Hip Replacement: replaces damaged surfaces with implants and helps to relieve pain and restore mobility
Define fractured neck of femur (#NOF) 6️⃣
Fracture of the proximal femur, up to 5cm below the lesser trochanter
How are #NOFs classified? 6️⃣
- intracapsular
- extracapsular - further divided into intertrochanteric and subtrochanteric
Classification is important as the site of the fracture has implication for the blood supply and therefore viability of the femoral neck
What implications to blood supply are intracapsular fractures likely to cause? 6️⃣
- disrupt ascending cervical (retinacular) branches of the MFCA
- due to inability of the Artery of the Ligamentum Teres to sustain the metabolic demand of the femoral head, there is a high risk of avascular necrosis of the bone.
- Risk increased if fracture displaced
*with extracapsular fractures, retina your arterial supply to the femoral head to likely to remain intact
Who are #NOFs common in and when can they occur?6️⃣
-intracapsular fractures: elderly esp post-menopausal women with osteoporotic bone.
Usually after a minor fall
-extracapsular fractures: young and middle aged population
Usually result of significant traumatic force
How is a displaced #NOF treated in an older person? 6️⃣
Due to high risk of a vascular necrosis, treated by surgical replacement of the femoral head or a total hip replacement.
What are the symptoms of a #NOF? 6️⃣
- reduced mobility/ sudden inability to bear weight on the limb
- pain which may be felt in the hip, groin and/or knee
Upon physical examination, how does a displaced #NOF present? 6️⃣
affected leg usually:
- shortened
- abducted
- externally rotated
There us exacerbation of pain on palpating if the greater trochanter and pain is exacerbated by rotation of hip
Why is the hip shortened, abducted and externally rotated in a displaced #NOF? 6️⃣
- the #NOF allows shaft of femur to move independently of the hip joint
- the axis of rotation of femur that normally passes obliquely through the head and down the neck of the femur, shifts to pass through the greater trochanter and vertically down the long axis of the femoral shaft
- the short lateral rotators of the hip (piriformis, obturator internus, superior and inferior gemelli and quadratus femoris) contract and externally rotate the femoral shaft. Iliopsoas also now acts as a lateral rotator of the femur as it pulls the lesser trochanter anteriorly about the new axis of rotation so the femoral shaft rotated externally
- the string abductors that attach to the greater trochanter abduct the femur dusts, to the fracture sire. They also rotate the greater trochanter laterally about the new longitudinal axis
- shortening occurs because the strong muscles of the thigh pull the distal fragment of the femur upwards. This includes the rectus femoris, adductor Magnus and hamstrings
Define dislocation of the hip 7️⃣
The head of femur being fully displaced out of the cup shaped acetabulum of the pelvis
Describe congenital dislocations 7️⃣
- developmental dysplasia of the hip
- not always congenital, can develop after birth
Describe traumatic hip dislocation 7️⃣
- acute traumatic hip dislocation
- affected hip extremely painful and patient resists attempt to move the limb
- 90% posterior
- most common cause is knee impacting dashboard during road traffic collisions
- affected limb shortened and held in position of flexion, addiction and internal rotation
- sciatic nerve palsy in 8-20% cases
Why do shortening and internal rotation of the limb occur after the posterior dislocation of the hip? 7️⃣
- femoral head pushed backwards over posterior margin of acetabulum and comes to lie on lateral surface of the ilium. Head of femur pulled upwards by strong extensors (gluteus maximums and hamstrings) and hip adductors, causing limb shortening
- anterior fibres of gluteus medius and minimus pull on the posteriorly displaced greater trochanter, causing internal rotation.
Describe anterior hip dislocation 7️⃣
- limb held in position of external rotation and abduction with slight flexion
- femoral nerve pulses can be present but uncommon
Describe central hip dislocation 7️⃣
- femoral head driven into pelvis through acetabulum
- always a fracture-dislocation
- femoral head palpable on rectal examination
- High risk of intrapelvic haemorrhage due to disruption of the pelvic venous plexuses- life-threatening
