Case 25- anatomy Flashcards
The location of the lesser trochanter
Medial aspect of the proximal femur
The location of the intertrochanteric crest
Running between the greater and lesser trochanters on the posterior aspect of the proximal thigh
The location of the gluteal tuberosity
Inferior to the intertrochanteric crest on the posterior aspect of the proximal femur, attachment of the gluteus maximus
The location of the quadrate tuberosity
Approximately half-way along the intertrochanteric crest on the posterior aspect of the proximal femur. Attachment of the quadratus femoris
The location of the Pectineal line
Running inferiorly from the lesser trochanter on the postero-medoal aspect of the proximal femur, attachment of the pectineis
The location of the intertrochanteric line
Running between the greater and lesser trochanters on the anterior aspect of the proximal femur
Intracapsular ligaments of the hip
- Transverse acetabular ligament: Completes the labrum and forms acetabular foramen.
- Ligamentum teres: (ligament of the head of femur): Connects the fovea to the acetabulum. Provides passage for acetabular branch of obturator artery (artery of ligament of head of femur) into the head of the femur.
- The intrinsic hip ligaments restrict extension
Intrinsic (Extracapsular) ligaments of the hip
- Ischiofemoral ligament: Supports the posterior aspect of the hip joint. Limits extension and medial rotation. Holds the femoral head in the acetabulum
- Iliofemoral ligament: Supports anterior/superior aspect of hip joint. Limits extension and lateral rotation of the hip. Main role is to prevent extension
- Pubofemoral ligament: Supports anterior/inferior aspect of the hip joint. Limits extension and lateral rotation of the hip. Limits medial rotation
What type of joint is the hip joint
The hip joint is a multi-axial ball and socket synovial joint. The shape of the acetabulum and support of ligaments and muscles around the joint increase the stability of the joint but reduce the range of movement (when compared to the shoulder joint).
Head of femur
Covered in articular hyaline cartilage except the fovea. Only 50% of the head articulates with the acetabulum at any one time
Acetabulum
1) Meaning ‘vinegar cup’. The articular (lunate) surface is covered in hyaline cartilage.
2) Non-articulating acetabular fossa contains a fat pad for joint cushioning.
3) Deepened by a fibrocartilaginous acetabular labrum in an incomplete ring.
4) Remaining inferior portion of the ring is completed by the transverse acetabular ligament.
5) Vessels and nerves to the hip joint enter through the acetabular foramen beneath the transverse acetabular ligament.
Ligament of the Head of the Femus
Meaning ‘vinegar cup’. The articular (lunate) surface is covered in hyaline cartilage. Non-articulating acetabular fossa contains a fat pad for joint cushioning. Deepened by a fibrocartilaginous acetabular labrum in incomplete ring. Remaining inferior portion of the ring is completed by the transverse acetabular ligament. Vessels and nerves to the hip joint enter through the acetabular foramen beneath the transverse acetabular ligament.
Joint capsule- hip bone
Strong fibrocartilaginous capsule. Non-articular surfaces are lined with synovial membrane. IIiopsoas bursa protects the tendon of iliopsoas from the anterior aspect of the hip joint. Ring of circular fibres of capsule forms orbicular zone. Intrinsic ligaments provide joint stability.
Angles of movement- Hip
- Lateral rotation (60 degrees) Limited by iliofemoral and pubofemoral ligaments, and the medial rotators
- Flexion (120 degrees). Limited by soft tissue and tension in hip extensors
- Extension (25 degrees). Limited by the extracapsular ligaments
- Abduction (45 degrees). Limited by the adductor muscles, and pubofemoral and iliofemoral ligament
- Adduction (20-30 degrees). Limited by the abductors, and also soft tissue apposition (the other lower limb).
- Medial rotation (30 degrees) Limited by the ischiofemoral ligament, and lateral rotators
External (lateral rotation) of the hip joint
- Piriformis (sacrum to greater trochanter, nerve to piriformis)
- Superior gemellus (ischium to greater trochanter, nerve to obturator internus)
- Obturator internus (obturator membrane to greater trochanter, nerve to obturator internus)
- Gemellus inferior (ischium to greater trochanter, nerve to quadratus femoris)
- Quadratus femoris (ischium to quadrate tubercle, nerve to quadratus femoris)
- Obturator externus (obturator membrane to greater trochanter, obturator nerve)
Internal (medial rotation)
- Gluteus medius (ilium to greater trochanter, superior gluteal nerve)
- Gluteus minimus (ilium to greater trochanter, superior gluteal nerve)
- Tensor fasciae latae (ilium to iliotibial tract, superior gluteal nerve)
Hip abductors
- Gluteus medius (ilium to greater trochanter, superior gluteal nerve)
- Gluteus minimus (ilium to greater trochanter, superior gluteal nerve)
Abductor weakness
Trendelenburg’s sign can indicate abductor muscle weakness or superior gluteal nerve damage. This sign is characterised by a pelvis drop on the non weight bearing side during locomotion.
Hip adductors
- Adductor magnus (pubis and ischium to linea aspera and adductor tubercle, obturator nerve)
- Adductor longus (pubis to linea aspera, obturator nerve)
- Adductor brevis (pubis to linea aspera, obturator nerve)
- Gracilis (pubis to pes anserinus of tibia, obturator nerve)
- Pectineus (pectineal line of pubis to pectineal line of femur, femoral and obturator nerve)
- Obturator externus (obturator membrane to greater trochanter, obturator nerve)
Hip flexors
- Iliopsoas (ilium and vertebral column to lesser trochanter, femoral nerve)
- Sartorius (anterior superior iliac spine to pes anserinus of the tibia, femoral nerve)
- Rectus femoris (anterior inferior iliac spine to patella tendon, femoral nerve)*
- Tensor fasciae latae, pectineus, adductor longus, adductor brevis and gracilis also contribute to hip flexion.
Hip extensors
- Gluteus maximus (ilium to gluteal tuberosity, inferior gluteal nerve)
- Semitendinosus (ischium to pes anserinus of tibia, tibial division of sciatic nerve)
- Semimembranosus (ischium to medial tibia, tibial division of sciatic nerve)
- Biceps femoris (long head ischium and short head linea aspera to fibula, tibial division of sciatic nerve)
- Hamstring part of adductor magnus (ischium to adductor tubercle, tibial division of sciatic nerve)
Shenton’s line
An imaginary curved line from the inferomedial aspect of the femoral shaft and femoral neck and the superior border of the obturator foramen, this line should be smooth and continuous. Disruption in this line could be a fractured neck of the femus or developmental dysphasia of the hip.
Common hip fractures
Hip fractures include an intertrochanteric fracture, femoral shaft (sub-trochanteric) fracture and a femoral neck fracture.
Traumatic hip dislocation
Typically occurs in cases of major trauma. Most commonly its posterior dislocation (i.e. in a road traffic accident). Fractures of the acetabular rim and damage to the posterior thigh structures (including the sciatic nerve) can occur in posterior dislocation. Anterior dislocation can also occur.
Development dysphasia of the hip
Congenital hip displacement can occur in neonates when the head of the femur does not articulate with the malformed, shallow acetabulum.
Osteoporosis
Reduced bone density and mass
Equal loss of mineral and organic matrix
Increased risk of fractures
Osteoporosis- Pathogenesis
1) Uncoupling of normal balance between bone formation and resorption
2) Bone resorption exceeds bone formation-too much resorption (high turnover), too little formation (low turnover)
3) Bone present is biochemically normal
Risk factors for osteoporosis (women)
USA: 1:2 female > 50 years will suffer an osteoporosis-related fracture (male = 1 in 8)
Why- females have a lower bone mass and oestrogen is involved
Most frequent in postmenopausal women- natural loss with ageing exacerbated. Lack of oestrogen promotes bone resorption (high turnover). Most bone loss in the first ten years after the menopause or oophorectomy
Other risk factors for osteoporosis
1) Genetics
2) Ethnicity- northern european and Asian
3) Smoking and alcohol
4) Immobilisation- low physical activity, astronauts
5) Drug induces= corticosteroids inhibit bone formation (low turnover)
6) Testosterone deficiency (males)- hypogonadism
Major risk factors for osteoporosis
History of fracture as an adult
Fragility fracture in first degree relative
Low body weight (< 127 lb)
Additional risk factors for osteoporosis
Impaired vision Oestrogen deficiency at early age (< 45) Dementia Poor health/frailty Recent falls Low calcium intake (lifelong)
What conditions increase the risk of osteoporosis
COPD Cushing’s syndrome Eating disorders Hyperparathyroidism Hypophosphatasia IBS RA - autoimmune connective tissue disorders Insulin dependent diabetes Multiple sclerosis Multiple myeloma Stroke (CVA) Thyrotoxicosis Vitamin D deficiency Liver diseases
Postmenopausal osteoporosis- therapy for prevention and treatment (Oral bisphosphonates)
1) First-line choices - alendronic acid, risedronate sodium
2) Anti-fracture efficacy
3) Reduce occurrence of vertebral, non-vertebral and hip fractures
4) Adsorbed onto hydroxyapatite
5) Induce apoptosis of osteoclasts
6) Reduces rate of bone turnover
Intravenous bisphosphonates
Ibandronic acid, zoledronic acid, denosumab, raloxifene hydrochloride alternative if intolerant of oral bisphosphonates or contra-indicated.
Postmenopausal osteoporosis- therapy for prevention and treatment (HRT)
Younger postmenopausal females with menopausal symptoms who are at a high risk of fractures. Risk of adverse effects- cardiovascular, cancer in older postmenopausal females and long term HRT therapy
Postmenopausal osteoporosis- therapy for prevention and treatment (Teriparatide)
Treatment is limited to 24 months
Reserved for postmenopausal females- severe osteoporosis
High risk of vertebral fractures
Glucocorticoid induced osteoporosis
Glucocorticoid therapy associated with bone loss and increased risk of fractures
Bone-protection treatment should be started at the onset of therapy if risk fractures
Oral bisphosphonates - First-line treatment
Osteoporosis in men
Long-term androgen deprivation therapy for prostate cancer - increased fracture risk
Oral bisphosphonates - First-line treatment
Useful investigations in diagnosing bone disease
X-ray BMD ( DEXA calcaneum) Screening DEXA ( Dual Energy X–Ray Absorptiometry) FRAX Hormone levels Quantitative CT Scan Body Composition Analysis to detect bone loss MRI
Dual energy x-ray absorptiometry (DEXA)
Diagnose of assess risk of osteoporosis
Measure BMD before starting treatment that may have an adverse effect on bone density- se hormone deprivation for treatment for breast or prostate cancer
When may they be recommended to measure BMD
1) Have had a broken bone after a minor fall or injury
2) Have arthritis
3) Take oral glucorticoids for three months
4) Early menopause
5) Postmenopausal women- smoke or drink excessively, family history or hip fractures, BMI <21
6) Large gaps between periods (>years)
Osteomalacia (Rickets in children)
Inadequate mineralisation of new bone matrix or osteoid
Rickets is defective mineralisation at the epiphyseal growth plates
Causes of rickets/osteomalacia- deficient intake or absorption of vitamin D
Inadequate sun exposure
Low dietary intake
Malabsorption: Coeliac disease, Crohn’s disease, Primary biliary cirrhosis, Gastrectomy
Causes of rickets/osteomalacia- Dietary 1-alpha hydroxylation
Chronic kidney disease
Vit D dependent Rickets type I (Lack of 1α-Hydroxylase)
Causes of rickets/osteomalacia- Primary renal PO4 wasting
Renal tubular acidosis
Fanconi syndrome
X-Linked hypophosphatemia
Other causes of rickets/osteomalacis
Inhibitors of mineralisation- Fluoride, Aluminium. Metabolic acidosis
Defective vitamin D receptors- Vit D dependent Rickets type II
Clinical features of rickets- at birth
craniotabes, softened occipital bones, flattened parietal bones can be buckled
Clinical features of rickets- Early years
Widened epiphyses (wrists), frontal bossing, squared appearance to the head
Presence of Rickety rosary - Beading at costo-chondral joints
Groove in the rib cage (Harrison’s sulcus)
Pigeon chest
Clinical features of rickets in older children
Lower limb deformities Myopathy Lumbar lordosis and bowing of the legs Hypocalcemic tetany (severe cases)
Clinical features of osteomalacis
Usually asymptomatic- identified incidentally in routine investigation
Symptomatic=
Proximal Muscle weakness
Widespread bone pain – tenderness, hydration of the demineralized matrix
Dull pain, worse on weight bearing
Insufficiency fracture= stress upon weakened bone - bone elastic resistance decreased
Abnormal gait
Laboratory tests for osteomalacia
Serum Calcium (normal in Osteoporosis) Plasma Phosphate Vitamin D status T4, TSH PTH FSH Testosterone Bone Specific Alkaline Phosphatase (Bone ALP / BALP) Type 1 Collagen propeptides Bone resorption and Bone Formation Markers
