Overview

Definition

Slipped capital femoral epiphysis (SCFE) is a hip disorder common in adolescence that features the displacement of the capital epiphysis of the femoral head through the growth plate (physis) in relationship to the femoral neck.

Slipped capital femoral epiphysis (SCFE) is considered a Salter-Harris type 1 fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures, because SCFE is a transverse fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures through the growth plate or physis.

Classification

There are several classification systems for SCFE:

• Temporal classification: time of presentation:
  • Acute: < 3 weeks
  • Chronic: > 3 weeks
• Loder classification of stability: based on the ability to bear weight:
  • Stable: ambulation possible
  • Unstable: ambulation not possible
• Southwick slip angle classification: femoral epiphyseal-diaphyseal angle difference:
  • Mild: < 30° 
  • Moderate: 30°–50°
  • Severe: > 50°
• Gradation: based on the percentage of slippage:
  • Grade I: 0%–33%
  • Grade II: 34%–50%
  • Grade III: > 50%

Epidemiology

• Incidence 1 in 1,000–10,000 children in the United States
• Mean age of presentation is 12–13 years.
• Male : female ratio 2.5:1
• More common in Pacific Islanders, Latinx, and Black adolescents 
• Left hip more commonly affected in unilateral cases
• Bilateral in 20%–40% of cases (up to 100% of patients with endocrine disease) 
• Associated with:
  • Obesity Obesity Obesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors. Obesity (the severity of disease worsens in parallel with obesity)
  • Hypothyroidism Hypothyroidism Hypothyroidism is a condition characterized by a deficiency of thyroid hormones. Iodine deficiency is the most common cause worldwide, but Hashimoto's disease (autoimmune thyroiditis) is the leading cause in non-iodine-deficient regions. Hypothyroidism
  • Hypogonadism Hypogonadism Hypogonadism is a condition characterized by reduced or no sex hormone production by the testes or ovaries. Hypogonadism can result from primary (hypergonadotropic) or secondary (hypogonadotropic) failure. Symptoms include infertility, increased risk of osteoporosis, erectile dysfunction, decreased libido, and regression (or absence) of secondary sexual characteristics. Hypogonadism
  • Panhypopituitarism 
  • Growth hormone disorders 
  • Several genetic disorders (e.g., Rubenstein-Taybi syndrome, Down’s syndrome)

Etiology

The causes of SCFE are multifactorial, a combination of endocrine and biomechanical factors. Excessive mechanical forces causing more shearing forces to be applied to the femoral neck result in the failure of a susceptible (weakened) physis.

• Increased mechanical forces: 
  • Increased body weight 
  • Trauma 
• Weakened physis:
  • Widening of the epiphysis and periosteal thinning during periods of rapid growth (e.g., pubertal growth) 
  • Chronic inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body's defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation of the joint
  • Endocrine and metabolic disorders causing abnormal mineralization of cartilage Cartilage Cartilage is a type of connective tissue derived from embryonic mesenchyme that is responsible for structural support, resilience, and the smoothness of physical actions. Perichondrium (connective tissue membrane surrounding cartilage) compensates for the absence of vasculature in cartilage by providing nutrition and support. Cartilage and instability of the perichondrial ring:
    • Hypothyroidism Hypothyroidism Hypothyroidism is a condition characterized by a deficiency of thyroid hormones. Iodine deficiency is the most common cause worldwide, but Hashimoto's disease (autoimmune thyroiditis) is the leading cause in non-iodine-deficient regions. Hypothyroidism
    • Renal osteodystrophy
    • Growth hormone deficiency 
    • Panhypopituitarism
  • Radiation exposure for treatment of bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones cancers

Pathophysiology

Repetitive shear forces applied to a weakened physis result in fracture Fracture A fracture is a disruption of the cortex of any bone and periosteum and is commonly due to mechanical stress after an injury or accident. Open fractures due to trauma can be a medical emergency. Fractures are frequently associated with automobile accidents, workplace injuries, and trauma. Overview of Bone Fractures and slipping. As slippage progresses, the metaphysis translates anteriorly and superiorly while rotating externally; the epiphysis remains in the acetabulum.

Clinical Presentation

Children who present with SCFE typically complain of groin and anterior thigh Thigh The thigh is the region of the lower limb found between the hip and the knee joint. There is a single bone in the thigh called the femur, which is surrounded by large muscles grouped into 3 fascial compartments. Thigh pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain, and demonstrate an altered gait.  

• History:
  • Chief complaint: hip pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain without a history of trauma: 
    • May complain primarily of pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain in the ipsilateral knee
    • Pain in the groin, hip, knee, or thigh Thigh The thigh is the region of the lower limb found between the hip and the knee joint. There is a single bone in the thigh called the femur, which is surrounded by large muscles grouped into 3 fascial compartments. Thigh aggravated by physical exertion
  • Acute cases: severe and sudden pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain after injury or activity
  • Chronic cases: hip pain Pain Pain has accompanied humans since they first existed, first lamented as the curse of existence and later understood as an adaptive mechanism that ensures survival. Pain is the most common symptomatic complaint and the main reason why people seek medical care. Physiology of Pain for weeks or months
  • May report difficulty in daily activities (tying shoes)
• Physical examination:
  • Limping while walking or running (inability to walk in severe cases)
  • External rotation of the affected leg Leg The lower leg, or just "leg" in anatomical terms, is the part of the lower limb between the knee and the ankle joint. The bony structure is composed of the tibia and fibula bones, and the muscles of the leg are grouped into the anterior, lateral, and posterior compartments by extensions of fascia. Leg and loss of range of motion (ROM)
  • Length discrepancy of lower limbs (the affected limb is shorter)
  • Gait becomes antalgic as slippage progresses.

Diagnosis

The diagnosis of SCFE is performed through a combination of history, physical examination, and plain film X-rays X-rays X-rays are high-energy particles of electromagnetic radiation used in the medical field for the generation of anatomical images. X-rays are projected through the body of a patient and onto a film, and this technique is called conventional or projectional radiography. X-rays. 

• Hip X-rays X-rays X-rays are high-energy particles of electromagnetic radiation used in the medical field for the generation of anatomical images. X-rays are projected through the body of a patient and onto a film, and this technique is called conventional or projectional radiography. X-rays (anteroposterior (AP) and frog leg Leg The lower leg, or just "leg" in anatomical terms, is the part of the lower limb between the knee and the ankle joint. The bony structure is composed of the tibia and fibula bones, and the muscles of the leg are grouped into the anterior, lateral, and posterior compartments by extensions of fascia. Leg lateral views of both hips):
  • Lateral X-ray is the primary way to identify a subtle slip:
    • Epiphysiolysis: growth plate widening or lucency
  • Klein’s line: In AP view, a line drawn along the superior border of the femoral neck will intersect less of the femoral head in a child with SCFE; asymmetry between sides is key.
• Computed tomography (CT), magnetic resonance imaging (MRI), and bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones scans:
  • MRI may help diagnose a “preslip” condition.
  • If X-rays X-rays X-rays are high-energy particles of electromagnetic radiation used in the medical field for the generation of anatomical images. X-rays are projected through the body of a patient and onto a film, and this technique is called conventional or projectional radiography. X-rays normal, but SCFE suspicion high, MRI can demonstrate widening of the growth plate with surrounding edema Edema Edema is a condition in which excess serous fluid accumulates in the body cavity or interstitial space of connective tissues. Edema is a symptom observed in several medical conditions. It can be categorized into 2 types, namely, peripheral (in the extremities) and internal (in an organ or body cavity). Edema
• Hormone levels according to clinical suspicion of endocrinopathies

Management and Complications

Management

The treatment involves immediate non–weight-bearing status and referral to orthopedic surgery:

• Must be non–weight bearing to prevent further slippage
• Operative stabilization is the primary treatment:
  • Percutaneous screw fixation through the femoral neck, engaging the physis
  • Reduction of slipped epiphysis is not recommended because of increased risk of avascular necrosis.
  • Prophylactic pinning of the contralateral hip is controversial.
• Prognosis:
  • Mild cases with less slippage have a better prognosis.
  • More severe cases are at risk of developing osteoarthritis Osteoarthritis Osteoarthritis (OA) is the most common form of arthritis, and is due to cartilage destruction and changes of the subchondral bone. The risk of developing this disorder increases with age, obesity, and repetitive joint use or trauma. Patients develop gradual joint pain, stiffness lasting < 30 minutes, and decreased range of motion. Osteoarthritis at a young age.

Complications

• Osteonecrosis or avascular necrosis of the hip: loss of blood supply to the femoral head leading to necrosis of cartilage Cartilage Cartilage is a type of connective tissue derived from embryonic mesenchyme that is responsible for structural support, resilience, and the smoothness of physical actions. Perichondrium (connective tissue membrane surrounding cartilage) compensates for the absence of vasculature in cartilage by providing nutrition and support. Cartilage and bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones: 
  • Most concerning complication leading to worst outcome 
  • Increased risk seen with acute, unstable slips 
  • 10%–15% of children with SCFE develop osteonecrosis.
• Contralateral hip SCFE: increased risk in obese males with endocrine disorders
• Chondrolysis: destruction of hip cartilage Cartilage Cartilage is a type of connective tissue derived from embryonic mesenchyme that is responsible for structural support, resilience, and the smoothness of physical actions. Perichondrium (connective tissue membrane surrounding cartilage) compensates for the absence of vasculature in cartilage by providing nutrition and support. Cartilage: occurs with penetration of a stabilization pin into the joint during surgery
• Residual deformity with limb length discrepancy
• Femoroacetabular impingement (FAI): poor fit of the hip “ball in socket” causing grating and further injury with movement
• Degenerative arthritis with aging
• Non-union after surgical pinning

Clinical Relevance

• Avascular necrosis of the hip: necrosis and deformation of the femoral head due to impaired blood supply to the head of the femur. Development of avascular necrosis is a serious complication in SCFE or other conditions.
• Osteoarthritis or degenerative joint disease: progressive degeneration of the joint characterized by a loss of cartilage Cartilage Cartilage is a type of connective tissue derived from embryonic mesenchyme that is responsible for structural support, resilience, and the smoothness of physical actions. Perichondrium (connective tissue membrane surrounding cartilage) compensates for the absence of vasculature in cartilage by providing nutrition and support. Cartilage and growth of bone Bone Bone is a compact type of hardened connective tissue composed of bone cells, membranes, an extracellular mineralized matrix, and central bone marrow. The 2 primary types of bone are compact and spongy. Structure of Bones spurs. Patients with SCFE, due to femoral head deformity, are at risk of developing degenerative changes of the hip joint Hip joint The hip joint is a ball-and-socket joint formed by the head of the femur and the acetabulum of the pelvis. The hip joint is the most stable joint in the body and is supported by a very strong capsule and several ligaments, allowing the joint to sustain forces that can be multiple times the total body weight. Hip Joint and osteoarthritis Osteoarthritis Osteoarthritis (OA) is the most common form of arthritis, and is due to cartilage destruction and changes of the subchondral bone. The risk of developing this disorder increases with age, obesity, and repetitive joint use or trauma. Patients develop gradual joint pain, stiffness lasting < 30 minutes, and decreased range of motion. Osteoarthritis earlier in life.
• Legg-Calvé-Perthes disease Legg-Calvé-Perthes Disease Legg-Calvé-Perthes disease (LCPD) is characterized by idiopathic avascular necrosis of the femoral head. The disease presents as a limp with an insidious onset and associated hip pain. Legg-Calvé-Perthes disease primarily affects school-age children and has a male predominance. Legg-Calvé-Perthes Disease (LCPD) ( LCPD LCPD Legg-Calvé-Perthes disease (LCPD) is characterized by idiopathic avascular necrosis of the femoral head. The disease presents as a limp with an insidious onset and associated hip pain. Legg-Calvé-Perthes disease primarily affects school-age children and has a male predominance. Legg-Calvé-Perthes Disease (LCPD)): idiopathic avascular necrosis of the femoral head. Exact mechanism is unknown and diagnosis is made by clinical findings and diagnostic imaging. Treatment can be conservative or surgical, depending on the severity and the patient’s age.