Cephalopelvic disproportion

1) Disease Description (Causes and Symptoms)

• Definition and pathophysiology: Avascular necrosis of the femoral head (AVN of femoral head) is a disease in which insufficient blood supply to the femoral head causes bone tissue necrosis, eventually leading to collapse (depression) of the subchondral cortex and cancellous bone and the development of secondary arthritis. There may be no clear symptoms in the early stage, but as the lesion progresses, structural collapse, pain, and restricted movement occur.
• Main causes/risk factors: Excessive alcohol consumption and long-term or high-dose use of adrenocortical hormones (steroids) are major risk factors and account for a substantial proportion of all causes. Other associated factors include hip trauma (fracture/dislocation), decompression sickness, serum lipid abnormalities, blood coagulation disorders, and chronic kidney disease and chronic pancreatitis. Some cases are idiopathic.
• Clinical features: Gradual groin and buttock pain, worsening with activity, limping, limited internal rotation of the hip, and discomfort in a cross-legged (floor-sitting) position. When the lesion collapses, leg-length shortening and severe functional impairment may occur.
• Epidemiological features: It occurs most commonly in people in their 30s–50s, is more common in men, and may be bilateral in approximately 60% of cases.
• Diagnostic features: Plain X-rays may be normal in the early stage, limiting early diagnosis. MRI has high sensitivity and specificity and is useful for early detection. Bone scintigraphy (bone scan) may help with early diagnosis, but MRI is superior for determining lesion size and precise location.

2) Treatment Methods (Standard Treatment, Medications·Procedures·Surgery, Lifestyle Management, Precautions)

• Conservative treatment
  • Activity restriction and weight-bearing adjustment (temporary use of assistive devices is recommended for severe pain and early lesions)
  • Pain control: NSAIDs, acetaminophen, etc.
  • Correction of causes: Stop alcohol consumption; reduce or discontinue steroids if possible; treat lipid and coagulation abnormalities
  • Medication: Bisphosphonates (e.g., alendronate) may delay disease progression according to some studies, but the evidence is limited and inconsistent.
• Invasive/surgical treatment
  • Core decompression and multiple drilling: Performed to reduce micropressure and promote revascularization, mainly before femoral-head collapse (pre-collapse/early stage). The effects may be better when treatment is provided early, before cartilage collapse.
  • Bone grafting (autologous bone·allogeneic bone) and injection of bone marrow-derived stem cells: Performed at some institutions with the goal of promoting regeneration. Long-term, large-scale evidence for regenerative effects remains limited.
  • Osteotomy: Aims to preserve the joint by moving the necrotic area to a region subject to less weight-bearing. This is a partial indication for young, active patients.
  • Total hip arthroplasty (THA): The most definitive treatment when femoral-head collapse and joint destruction have progressed. It is considered preferentially in older patients or when the lesion is large.
• Rehabilitation and follow-up care
  • Stepwise postoperative weight-bearing instructions and physical therapy are needed, and prevention and management of DVT and infection are important.
  • Because the durability of artificial joints is limited, long-term follow-up and the possibility of revision surgery should be discussed.
• Precautions and complications
  • Possibility of progression based on the natural course of the disease (particularly a high likelihood of bilateral progression)
  • Femoral-head collapse and the need for joint replacement at an early stage if treatment is delayed
  • Surgical complications: infection, thrombosis, nerve injury, wear·adhesion·dislocation of the artificial joint, etc.

3) Outpatient Visit Checkpoints (Items to Bring and Things to Confirm)

• Items/documents to bring
  • List of currently used medications (including steroids) and allergy history
  • Previous test results (recent X-rays, MRI, bone scan, etc.) and surgical records (if applicable)
  • Pain diary (when it started, which activities make it worse, changes in pain intensity), exercise and occupational history (whether heavy loads are involved)
• Medical history points to confirm
  • Recent excessive alcohol consumption and drinking history (duration and amount)
  • History of steroid use (oral/injection) (duration and dosage)
  • History of hip trauma, diving·aviation history (if applicable)
  • Chronic diseases: autoimmune diseases (such as SLE), pancreatitis, kidney disease, blood coagulation disorders, etc.
• Standard outpatient tests (if ordered by the doctor)
  • Pelvic/hip X-ray (comparison of both sides), MRI (essential for early diagnosis), and bone scan if needed
  • Blood tests: blood lipids, liver and kidney function, blood coagulation tests, and, if necessary, tests for autoimmune and inherited coagulation disorders

4) Examples of General Questions to Ask the Doctor

• "What is the likelihood that my condition will improve with conservative treatment?"
• "Which tests do you recommend (such as MRI), and why?"
• "What treatment options do you recommend, and what are the advantages and disadvantages of each (recovery period, complications, and success rate)?"
• "What are the expected effects and side effects of medications (such as bisphosphonates)?"
• "If I undergo surgery, how long will recovery take, and what restrictions will there be on daily activities and exercise?"

5) Examples of Disease-Specific Questions (1–2 Questions Worth Asking First)

• "What stage is my current femoral-head necrosis at (for example, according to the ARCO or Ficat classification), and what are the size and location of the necrotic lesion (the overall and partial proportions)? Based on these results, what is the optimal recommended treatment?"
• "Can joint preservation be attempted with interventional treatments (such as core decompression or injection of bone marrow-derived stem cells)? Please explain the success rate and the likelihood of recurrence or additional surgery."

Note: The choice of diagnosis and treatment varies according to the individual patient's condition (stage, lesion size and location, age, activity level, comorbidities, etc.). Please determine the treatment plan based on subsequent test results and the doctor's opinion.