Introduction

Alendronate is an antiresorptive agent that reduces oedema and the rate of remodelling and prevents the progression of bone collapse.

Aim

To investigate efficacy of alendronate in the treatment of AVN of the hip

Patient Profile

60 Patients with AVN of the hip (100 hips with AVN)

Methods

• Prospective open-label study
• All the patients were treated with alendronate 10 mg per day (or 70 mg once a week), given early in the morning on an empty stomach with two glassfuls of water.
• All patients received daily 500–1000 mg of calcium and 400–800 IU vitamin D3. NSAIDs and analgesics were permitted as needed
• Patients were followed up every 3 months for the first year and every 6 months thereafter
• Parameters studied were walking time, standing time, pain, and disability on a visual analogue scale (VAS), range of motion of the hip, X-ray, and MRI of the hip

  Results

• There was significant improvement in all clinical parameters [walking time, standing time, pain, and disability (P<0.001)]

  Table 1: Mean range of motion on follow-up

  	0–1 yr (n = 71)	0–2 yr (n = 42)	0–2+ yr (n = 37)
  Flexion	98.8→102.9	101.2→106.4	100.5→103.8
  Extension	15.4→17.6	16.9→16.2	16.5→11.9
  Adduction	22.8→25.3	25→24.8	24.5→21.8
  Abduction	36.2→38.6	38.9→36.6	37.7→33.1
  Internal rotation	13.9→19.6	16.0→17.2	14.9→12.4
  External rotation	38.2→41.1	41.9→40.0	40→37.7

• There was significant reduction in pain and disability scores (P<0.001) and significant increase in standing and walking time (P<0.001)

  Table 2: Mean changes in pain, disability, walking time and standing time at follow up

  Parameters	0 and 1 yr (41 pts)	0 and 2 yr (24 pts)	0 and 2+ yr (21 pts)
  Pain (VAS)	6.0 à 2.2	6.1 à 1.6	6.6 à 2.0
  Disability (VAS)	5.2 à 2.3	4.9 à 1.7	4.8 à 2.4
  Standing time (min)	19 à 45	18 à 51	14 à 45
  Walking time (min)	16 à 41	16 à 46	12 à 37

   

   

  Table 3: X-ray grades of the hips with AVN

  X-ray grade	Baseline (100 hips)	1 yr (71 hips)	2 yr (42 hips)	2+ yr (37 hips)
  1	24	20	11	5
  2	42	24	14	13
  3	23	20	15	13
  4	11	7	2	6

   

   

  Table 4:  Radiological progression of AVN

  Years	No. of hips	Same grade	Progressed by one grade	Progressed by two grades
  0–1	71	61	10	0
  0–2	42	30	11	1
  0–2+	37	17	16	4

   

   

• Radiological deterioration was seen in 14% at 1 yr, 28% at 2 yr and 54% in the group with more than 2-yr of follow-up.
• All hip movements improved at 1 yr (P = 0.000–0.009) with an insignificant decline after that (P>0.001).
• MRI showed a decrease in marrow oedema in most cases at the 1-yr follow-up.
• 6 patients (10 hips) required surgery and there were 2 (3 hips) dropouts.
• Alendronate was well-tolerated and there was a reduction in NSAID requirement.

Conclusion

• Alendronate reduces pain, improves function and retards AVN progression. Early surgical intervention can be avoided in most patients.
• Treatment with alendronate is safe and gives early relief from pain with a reduced requirement for NSAIDs and delays the need for surgery.

Reference