Session 6 Flashcards
Describe the anatomy of the hip joint (bones, ligaments etc) LO
- The hip joint consists of an articulation between the ? of the pelvis.
- The acetabulum is a cup-like depression located on the inferolateral aspect of the pelvis. Its cavity is deepened by the presence of a fibrocartilaginous collar – the ?. The head of femur is hemispherical, and fits completely into the concavity of the acetabulum.
- Both the acetabulum and head of femur are covered in ?, which is thicker at the places of weight bearing.
- head of femur & acetabulum
- acetabular labrum
- articular cartilage
Intracapsular
- The only intracapsular ligament is the ligament of ? It is a relatively small structure, which runs from the ?
- It encloses a branch of the ? artery (?), a minor source of arterial supply to the hip joint .
- head of femur, acetabular fossa to the fovea of the femur
- obturator, artery to head of femur
Extracapsular
There are three main extracapsular ligaments, continuous with the outer surface of the hip joint capsule:
Iliofemoral ligament – spans between the anterior inferior iliac spine and the intertrochanteric line of the femur.
It has a ‘Y’ shaped appearance, & prevents hyperextension of the hip joint
Pubofemoral – spans between the superior pubic rami & the intertrochanteric line of the femur. It has a triangular shape, & prevents excessive abduction and extension.
Ischiofemoral – spans between the body of the ischium and the greater trochanter of the femur. It has a spiral orientation, and prevents excessive extension.
Describe the factors that stabilize the hip joint
- The primary function of the hip joint is to ?
- There are a number of factors that act to increase stability of the joint:
- In addition, the muscles and ligaments work in a reciprocal fashion at the hip joint:
- weight-bear
- acetabulum -deep, & encompasses nearly all of the head of the femur. This decreases the probability of the head slipping out of the acetabulum (dislocation).
+ acetabular labrum - increase in depth provides a larger articular surface
+ iliofemoral, pubofemoral & ischiofemoral ligaments - spiral orientation; this causes them to become tighter when the joint is extended.
+ reciprocal fashion
- Anteriorly, where the ligaments are strongest, the medial flexors (located anteriorly) are fewer and weaker.
Posteriorly, where the ligaments are weakest, the medial rotators are greater in number and stronger – they effectively ‘pull’ the head of the femur into the acetabulum.
Identify the muscles which produce movement at the hip joint
Flexion-
Extension-
Abduction-
Adduction-
Lateral rotation-
Medial rotation-
Flexion – iliopsoas, rectus femoris, sartorius, pectineus, tensor fascia lata
Extension – gluteus maximus, semimembranosus, semitendinosus & biceps femoris
Abduction – gluteus medius, gluteus minimus & the deep gluteals (piriformis, gemelli etc.)
Adduction – adductors longus, brevis & magnus, pectineus & gracillis
Lateral rotation – biceps femoris, gluteus maximus, & the deep gluteals (piriformis, gemelli etc.)
Medial rotation – gluteus medius & minimus (Assisting Muscles semimembranosus, semitendinosus, tensor fascia latae, & hip adductors)
The degree to which flexion at the hip can occur depends on whether the knee is ? – this relaxes the hamstring muscles, and increases the range of ?
Extension at the hip joint is limited by the ? These structures become taut during extension to limit further movement.
flexed, flexion
joint capsule and the iliofemoral ligament
Identify the neurovascular structures associated with the hip joint
- The arterial supply to the hip joint is largely via the ? – branches of the ? (deep femoral artery).
- They anastomose at the ? to form a ring, from which smaller arteries arise to supply the hip joint itself.
- The medial circumflex femoral artery is responsible for the majority of the arterial supply (the lateral circumflex femoral artery has to penetrate through the thick ?). Damage to the medial circumflex femoral artery can result in ?
- The artery to head of femur & the ? arteries provide some additional supply.
- The hip joint is innervated by the ?
- medial & lateral circumflex femoral arteries - branches of the profunda femoris artery
- base of the femoral neck
- iliofemoral ligament, avascular necrosis of the femoral head
- superior/inferior gluteal
- femoral nerve, obturator nerve, superior gluteal nerve, & nerve to quadratus femoris.
Describe the risk factors for osteoarthritis of the hip & the symptoms
described by patients; describe the limitations placed on their activities of daily living
(1. Definition
2. Classification of OA
3. Give examples for causes of secondary osteoarthritis
4. Characteristics of OA)
5. Arthritis risk factors LO
6. Arthritis signs and symptoms
7. OA of hip in men signs & symptoms
- Degenerative joint disease. A clinical syndrome of joint pain
accompanied by functional limitation and reduced QOL
- Primary OA = Etiology is unknown
Secondary OA = Etiology is known
- • Trauma
- Previous joint disorders;
- Developmental Dysplasia of the Hip (DDH)
- Infection: Septic arthritis, Brucella, Tb
- Inflammatory: RA, AS
- Metabolic: Gout
- Haematologic: Haemophilia
- Endocrine: DM
- • OA is a chronic disease of the
musculoskeletal system, without systemic involvement
- OA is mainly a non-inflammatory disease of synovial joints
- No joint ankylosis is observed in the course of the disease
- Obesity
Past injury in a joint Occupational factors Genetics
- Symptom:
Joint Pain
Crepitis (grinding)
Joint stiffness
Sign: Joint Deformity
- • Joint stiffness • Pain of hip, gluteal and groin areas
radiating to the knee (N obturatorius) • Mechanical pain • Limited walking function
Which one is the arthritic hip?
How do you know?
Describe & identify the features of osteoarthritis of the hip on an X-ray LO
- Bloods
- FBC, U&Es, LFTs, ESR, CRP
- Imaging- 4 cardinal signs on Xray?
- Subchondrial sclerosis
- Osteophytes
- Narrowing of joint space
- Subchondrial cysts
Management
Structure of joint cartilage
- Collagen (Type 2)
- Proteoglycan
- Hyaluronic acid
- Glycoseaminoglycan
- Water
- Chondrocyte
Regeneration & Degeneration
Articular cartilage is the main tissue affected OA results in:
- Increased tissue swelling
- Change in color
- Cartilage fibrillation
- Cartilage erosion down to subchondral bone
The cartilage damage causes chondrocyte cloning in an attempt to restore articular surface (Normal adult chondrocytes are
fully differentiated and do not proliferate)
What is this image showing
Osteoarthritis:
lateral osteophyte, loss of articular cartilage & some subchondral bony sclerosis- X-ray shows loss of joint space
(Subchondral cysts- last sign)
Describe the common fractures of the hip & femoral shaft, their radiological appearance, & their complications with regard to adjacent anatomical structures LO
Describe the mechanism underlying avascular necrosis of the hip following an intracapsular fracture of the femoral neck, relating this to the vascular anatomy of the hip LO
Describe the mechanism underlying avascular necrosis of the hip following
an intracapsular fracture of the femoral neck, relating this to the vascular
anatomy of the hip
Have a basic understanding of the major methods available for treatment of
femoral neck fractures (total hip replacement, hemiarthroplasty, dynamic
hip screw) & the anatomical reasons why they are commonly selected
(also see groupwork). LO
Describe the common clinical appearance of the limb after a displaced femoral neck fracture, relating the rotation and shortening of the limb to the function of the muscles LO
- Describe the common mechanisms of traumatic posterior dislocation of the hip?
- Where does the femur move?
- The typical clinical appearance, relating the rotation & shortening of the limb to the function of the muscles
- Damage to other structures?
- Describe the common mechanisms of traumatic anterior dislocation of the hip
- The typical clinical appearance, relating the rotation & shortening of the limb to the function of the muscles
- Damage to other structures?
LO
Congenital Dislocation
Congenital hip dislocation is known as developmental dysplasia of the hip (DDH). It occurs when the hip joint does not develop properly in utero.
Common clinical features include:
Limited abduction at the hip joint
Limb length discrepancy – the affected limb is shorter
Asymmetrical gluteal or thigh skin folds
DDH is usually treated with a Pavlik harness. This holds the femoral head in the acetabular fossa and promotes normal development of the hip joint. Surgery is indicated in cases that do not respond to harness treatment.
Acquired Dislocation
- uncommon
1. Trauma axial load on femur, typically hip flexed e.g. MVA (femur hits dashboard)
2. Posteriorly & superior to acetabulum
3. shortened & medially rotated (gluteus medius & minimus), flexed (hamstrings- biceps, plantaris?, popliteal), adducted (gracilis, abductor brevis, magnus, longus)
4. crush & stretch sciatic nerve, which extends from the lower back down the back of the legs, is the nerve most commonly affected. Injury to the sciatic nerve may cause weakness in the lower leg and affect the ability to move the knee, ankle and foot normally. Sciatic nerve injury occurs in approximately 10% of hip dislocation patients. The majority of these patients will experience some nerve recovery.
Osteonecrosis. As the thighbone is pushed out of the socket, it can tear blood vessels and nerves. When blood supply to the bone is lost, the bone can die, resulting in osteonecrosis (also called avascular necrosis). This is a painful condition that can ultimately lead to the destruction of the hip joint and arthritis.
Arthritis. The protective cartilage covering the bone may also be damaged, which increases the risk of developing arthritis in the joint. Arthritis can eventually lead to the need for other procedures, like a total hip replacement.
- traumatic extension, abduction & lateral rotation.
- The femoral head is displaced anteriorly & (usually) inferiorly in relation to the acetabulum.
- It is often associated with fractures of the femoral head.
