Surg_Hip Arthroplasty 2024 (1)

GENERAL POINTS ABOUT THE HIP

  • Structure:

    • A ball-and-socket joint between the head of the femur and the lunate surface of the acetabulum.

    • Ligamentum teres connects the non-articular acetabular fossa to the femoral head.

Movements:

  • Flexion: Iliacus, psoas major (anterior rami L2-L4), rectus femoris, pectineus

  • Extension: Gluteus maximus, hamstrings.

  • Abduction: Gluteus medius, minimus.

  • Adduction: Adductors (magnus, longus, brevis), pectineus, gracilis (obturator nerve)

  • Internal Rotation: gluteus medius and minimus (superior gluteal nerve)

  • External rotation: Gluteus maximus, piriformis, obturator externus/internus, gemellus and quadratus femoris

LIGAMENTS OF THE HIP

  • Iliofemoral Ligament:

    • Y-shaped; from AIIS to intertrochanteric line; supports the anterior capsule.

  • Ischiofemoral Ligament:

    • Reinforces the posterior capsule and resists excessive extension.

  • Pubofemoral Ligament:

    • Supports the inferior capsule against excessive extension and abduction.

ARTERIAL SUPPLY

  • Trochanteric anastomosis with contributions from four arteries around the greater trochanter. Minor supply from artery of ligamentum teres.

OSTEOPARTHRITIS OF THE HIP

Characteristics

  • Common in patients over 40.

  • Symptoms include pain exacerbated by activity and relieved at rest.

  • Progression may lead to night pain and functional limitations.

Investigations and Management

  • Investigations: X-rays for joint space evaluation. LOSS (Loss of joint space, Osteophytes, Subcondral sclerosis, Subchondral cysts)

  • Management Options:

    • Non-operative: Analgesia, physiotherapy, weight loss.

    • Operative: Total Hip Replacement (arthroplasty).

HIP FRACTURES

Types of Fractures

  • Intracapsular:

    • Neck of femur, femoral head fractures.

  • Extracapsular:

    • Intertrochanteric, subtrochanteric fractures.

Intracapsular Clinical Features

  • Common in the elderly; related to fragility fractures.

  • Classic presentation involves pain, shortened externally rotated, slightly abducted hip.

Neck of Femur Fractures

  • Garden Classification:

    • Describes displacement and type of fracture; guides management strategies.

MANAGEMENT STRATEGIES

For Intracapsular Neck of Femur Fractures

  • Undisplaced Fractures (Garden I + II):

    • Managed with cannulation screws or DHS with derotation screw.

  • Displaced Fractures (Garden III + IV):

    • Usually treated with hemiarthroplasty in older patients; total hip replacement in younger, active patients.

Complications

  • Avascular Necrosis (AVN): risk factors include delayed surgery, displacement, non-anatomical reduction; MRI is diagnostic of choice.

  • Non-union: Similar risks as AVN, with additional lack of compression across the fracture.

INTEGRATED CARE PATHWAY FOR HIP FRACTURES

Hip Fracture Care Pathway

  • Pre-Hospital:

    • Adequate pain management, hydration, and fracture immobilization during transport to an orthopedic-capable hospital.

  • Emergency Department:

    • Assessment, X-rays, femoral nerve block, and blood tests.

    • Rapid referral for orthopedic and geriatric assessment, ideally transferred to a dedicated orthopedic ward within 4 hours and surgery within 48 hours.

  • Preoperative:

    • Pain control, oxygen administration, and timely preoperative investigations.

  • Postoperative:

    • Thromboprophylaxis, mobilization, physical therapy, and assessments by geriatrics and occupational therapy for rehabilitation and falls prevention.