A traumatic hip dislocation occurs when the femoral head (thighbone) is forcibly ejected from its socket in the hip bone (pelvis). Such an event typically results from major impacts like car accidents or falls from great heights and is frequently accompanied by other injuries, such as fractures.
Hip Joint Anatomy The hip joint is a ball-and-socket structure, comprising:
- The acetabulum, a socket part of the pelvis.
- The femoral head, which forms the ball at the top of the femur.
Both the ball and socket are covered in articular cartilage, facilitating smooth movement. The acetabulum is also surrounded by fibrocartilage called the labrum, which provides additional stability, supported by strong ligaments.
Description of Hip Dislocations A hip dislocation involves the femoral head being displaced either backward (posterior dislocation) or forward (anterior dislocation).
- Posterior Dislocation: This is the most common type, occurring in about 90% of cases, where the femur is pushed backward, causing the lower leg to rotate inward.
- Anterior Dislocation: Less common, this involves the femur slipping forward, with the knee and foot rotating outward.
These dislocations often damage the ligaments, labrum, muscles, and other soft tissues around the joint. Nerve injuries can also occur.
Causes Traumatic hip dislocations are typically caused by:
- Motor vehicle accidents, especially when the knee impacts the dashboard.
- Falls from significant heights.
- Industrial accidents.
- Sports collisions, such as in rugby or football.
Dislocations are often accompanied by other injuries, including fractures in the pelvis and legs, and injuries to the back, abdomen, and head. A frequent associated injury is a posterior wall acetabular fracture-dislocation.
Symptoms: A hip dislocation causes severe pain, making it impossible for patients to move their leg. If nerves are damaged, there may also be a loss of sensation in the foot or ankle.
Diagnosis and Examination Hip dislocations are medical emergencies requiring immediate attention. Do not attempt to move the injured individual; keep them warm with blankets.
An orthopaedic surgeon can often diagnose a dislocation based on the leg’s position. Imaging tests, such as X-rays and CT scans, are used to confirm the diagnosis and identify additional injuries.
Treatment Options Reduction Procedures If there are no other injuries, an orthopaedic surgeon will perform a reduction, manipulating the bones back into position under anaesthesia or sedation. Surgery may be needed if loose tissues or fragments block the femur from returning to the socket.
Nonsurgical Treatment If the hip joint is stable and no fractures are present, nonsurgical treatment may be recommended. This involves avoiding weight-bearing on the injured leg for 6 to 10 weeks and avoiding certain leg positions.
Surgical Treatment Surgery is required if there are associated fractures or if the hip remains unstable after reduction. The aim is to restore stability and align the cartilage surfaces, which often involves a large incision and may require a blood transfusion.
Complications Hip dislocations can lead to long-term issues, including:
- Nerve Damage: The sciatic nerve is frequently affected, causing weakness in the lower leg.
- Osteonecrosis: Loss of blood supply to the bone can result in bone death and arthritis.
- Arthritis: Damage to the cartilage can lead to arthritis, potentially requiring hip replacement surgery.
Recovery Recovery from a hip dislocation can take 2 to 3 months, longer if fractures are involved. Physical therapy is essential for rehabilitation, with patients typically starting to walk with crutches shortly after the injury. Walking aids help restore mobility during the recovery period.
In conclusion, traumatic hip dislocations are severe injuries requiring prompt medical intervention and a comprehensive treatment plan to ensure proper healing and recovery.
