Dislocation Hip, Total hip replacement

  • Anatomy of Hip joint ( Dislocation Hip)
    • hip joint is a ball and socket joint with inherent stability (MCQ)
    • Stability is largely as a result of the adaptation of the articulating surfaces of the acetabulum and femoral head to each other.
    • The capsule and ligaments of the joint provide additional stability.
    • Acetabulum faces an angle of 30° outwards and anteriorly(MCQ)
    • The normal neck-shaft angle of the femur is 125° in adults, with 15° of anteversion. (MCQ)
    • Neck is made up of spongy bone with aggregation of bony trabeculae along the lines of stress.
    • Blood supply of the femoral head:
      • Three main sources
        • medullary vesselsfrom the neck
        • retinacular vesselsentering from the lateral side of the head
        • foveal vesselfrom the ligamentum teres.
      • Most important are medullary vessels, retinacular vessels
        • generally cut off following a fracture of the neck of the femur
        • result in avascular necrosis of the head.
    • The abductor mechanism of the hip
      • When a person stands on one leg, the body weight tends to tilt the pelvis down on the other side. (MCQ)
        • The ipsilateral hip acts as a fulcrum in this.
        • The abductors of the hip on the side on which one is standing, contract to counter this
        • This helps in keeping the pelvis horizontal.
      • This abductor mechanism  is disrupted in conditions like dislocation of the hip, fracture of the neck of the femur
  • Dislocations of the hip
  • Classification
    • posterior dislocation (the commonest) (MCQ)
    • anterior dislocation
    • central fracture-dislocation.
  • All of these may be associated with fracture of the lip of the acetabulum.
  • Posterior dislocation of the hip
  • The head of the femur is pushed out of the acetabulum posteriorly
  • In about 50 per cent of cases, this is associated with a chip fracture of the posterior lip of the acetabulum, in which case it is called a fracture-dislocation.
  • The injury is sustained by violence directed along the shaft of the femur, with the hip flexed. – also known as dashboard injury. (MCQ)
  • Deformity – flexion, adduction and internal rotation(MCQ)
  • This is associated with a shortening of the leg(MCQ)
  • One may be able to feel the head of the femur in the gluteal region.
  • Why is it  “wise to X-ray the pelvis in all patients with fracture of the femur (MCQ)
      • Dislocation is sometimes missed, especially when associated with other more obvious injuries such as fracture of the shaft of the femur
      • Dislocation may go unnoticed in an unconscious patient
    • Radiological features:
      • femoral head is out of the acetabulum (MCQ)
      • thigh is internally rotated so that the lesser trochanter is not seen(MCQ)
      • Shenton’s line is broken. (MCQ)
    • Treatment
      • Reduction of a dislocated hip is an emergency, since longer the head remains out, more the chances of it becoming avascular.
      • In most cases it is possible to reduce the hip by manipulation under general anaesthesia.
      • The chip fracture of the acetabulum, if present, usually falls in place as the head is reduced. (MCQ)
      • Open reduction -Indications
        • closed reduction fails, usually in those presenting late
        • if there is intra-articular loose fragment not allowing accurate reduction
        • if the acetabular fragment is large and is from the weight bearing part of the acetabulum. Such a fragment makes the hip unstable.
    • Complications
      • Injury to the sciatic nerve: (MCQ)
        • The sciatic nerve lies behind the posterior wall of the acetabulum.
        • Treatment:
          • Injury is a neurapraxia in most cases and recovers spontaneously(MCQ)
          • In cases where the fragment of the posterior lip is not reduced by closed method, open reduction of the fracture, and nerve exploration may be required.
          • If the sciatic nerve is severely damaged at this level, prognosis is poor.
      • Avascular necrosis of the femoral head
      • Osteoarthritis:
        • Commonly, a total hip replacement is required
      • Myositis ossificans
  • Anterior dislocation
    • usually sustained when the legs are forcibly abducted and. externally rotated. (MCQ)
    • This may occur in a
      • fall from a tree when the foot gets stuck and the hip abducts excessively(MCQ)
      • in a road accident.
    • Clinically, the limb is in an attitude of external rotation (MCQ)
    • There may be true lengthening,with the head palpable in the groin(MCQ)
  • Central fracture-dislocation of the hip
    • In this common injury
    • femoral head is driven through the medial wall of the acetabulum towards the pelvic cavity
    • Joint stiffness and osteoarthritis are inevitable.
    • skeletal traction is applied distally and laterally
    • If the fragments fall in place and reasonably reconstitute the articular margins, the traction is continued for 8-12 weeks(MCQ)
    • In some young individuals, in whom the fragments do not fall back in place by traction, surgical reconstruction of the acetabular floor may be necessary. (MCQ)
    • Complications – Hip stiffness, myositis and osteoarthritis

Hip anatomy
Hip anatomy

Hip anatomy
Hip anatomy

Hip prosthesis displaying aseptic loosening
Hip dislocation
Hip dislocation

Hip Replacment
Hip Replacment
An X-ray showing a right hip (left of image) has been replaced, with the ball of this ball-and-socket joint replaced by a metal head that is set in the femur and the socket replaced by a white plastic cup (clear in this X-ray)
Dislocated hip replacement
Dislocated hip replacement

hip prosthesis
hip prosthesis
A titanium hip prosthesis, with a ceramic head and polyethylene acetabular cup
Hip Replacment
Hip Replacment
Cement free implant 16 days after surgery. Femoral component is cobalt chromium combined with titanium which induces bone growth into the implant. Ceramic head. Acetabular cup coated with bone growth inducing material and held temporarily in place with a single screw.

This video is another example of the emergency management of a dislocated hip. This patient was injured in a motor vehicle accident and sustained a dislocation as well as a fracture of the femoral head. He tolerated the procedure well.

Hip Dislocations – Everything You Need To Know – Dr. Nabil Ebraheim

This video demonstrates the reduction of a dislocated hip and the placement of a femoral traction pin.

Hip dislocation

Hip Reduction Trauma, Kelly Barringer, MD
Hip dislocation reduction

Hip Dislocation Following Total Hip replacement – Everything You Need To Know – Dr. Nabil Ebraheim

Hip Dislocation , Sciatic Nerve Injury – Everything You Need To Know – Dr. Nabil Ebraheim

this video shows the pre and post pictures of a dislocated hip that was reduced

Dislocation reduction of the hip joint (sample)

This video demonstrates the reduction of a dislocated hip and the insertion of a traction pin. The video was posted several years ago and has been quite popular. I have reworked the video and improved its quality.

Sifu Jen Sam treats my 94 year old grandma for a suspected dislocation of her right hip. The x-ray does not indicate fracture. So we are trying to fix the dislocation.

Total Hip Replacement Surgery

Total Hip Replacement – Surgical Procedure – HD

This surgical video features a posterior total hip replacement. The patient has osteoarthritis, or wear and tear arthritis of the hip, causing pain, stiffness, and decreased range of motion which has persisted despite efforts to control symptoms with non-operative means. The operation is performed in the operating room with the patient under general or spinal anesthesia.
video hip surgical procedure for total hip replacement