{'fraction_non_alphanumeric': 0.022331397945511387, 'fraction_numerical': 0.013398838767306834, 'mean_word_length': 5.292134831460674, 'pattern_counts': {'":': 0, '<': 1, '<?xml version=': 0, '>': 2, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Skeletal manifestations of Marfan syndrome.

which are musculoskeletal. The genetic basis of Marfan syndrome is related to chromosome 15 that encodes fibrillin-1 and 2. As with most genetic diseases the nature and location of mutations in the genes are only an approximate guide to the severity of the phenotype unless the same mutation has been seen in other members of the same family or in similar unrelated patients. The estimated prevalence of the syndrome is about 10 cases per 100,000 births. Diagnosis is made by defining the involvement of multiple systems. The musculoskeletal criteria require at least four phenotypic expressions to be present. These include: pectus excavatum/carinatum, reduced upper to lower body segment ratio or hand span to length ratio of > 1.05, wrist and thumb signs, scoliosis of > 20 degrees or spondylolysthesis, reduced extension of the elbows < 170 degrees (also evident in the fingers, often referred to as spider-like hands due to flexion contractures of the interphalangeal joints), medially displaced medial malleoli, and protrusio acetabuli [1]. The wide variety of mutations affected by different subtypes of collagen abnormalities is responsible for the somewhat diverse phenotype. It is important to note that although the great majority of patients are diagnosed before the age of 10, few present with four skeletal criteria, developing them later in life [1]. While most characteristic abnormalities of the musculoskeletal system are easily recognized, protrusio acetabuli is often overlooked or non-apparent until clinical symptoms emerge. This review will focus on two of them: spinal manifestations and protrusio acetabuli Protrusio acetabuli The medial protrusion of the femoral head due to deepening of the femoral head is common in Marfan syndrome, affecting 31–100% of patients to varying degrees [2]. The clinical manifestations of protrusio acetabuli are hip joint stiffness and progressive limitation in activity related to joint pain, a waddling gait, limited range of motion, flexion contracture, a pelvic tilt with a resulting hyperlordosis of the lumbar spine, and eventual osteoarthritic changes. Locally progressive protrusion can lead to early hip pain and osteoarthritis