abdominal musculature absent with microphthalmia and joint laxity abdominal musculature absent with microphthalmia and joint laxity abdominal musculature absent with microphthalmia and joint laxity is a rare human disorder characterized mainly by ligamentous laxity, small eyes, a lack of abdominal muscles and facial anomalies. abdominal musculature absent with microphthalmia and joint laxity