Question: What is (are) Proximal symphalangism ?
Answer: Proximal symphalangism, which is also called Cushing's symphalangism, is a rare genetic condition characterized by the fusion of the proximal joints in the hands and feet. These individuals usually have straight fingers and are unable to make a fist. Other joints may also be affected, leading to stiff joints in the elbows, ankles and wrists. Hearing loss due to the fusion of the auditory ossicles (bones in the middle ear) is also a characteristic feature. This condition is inherited in an autosomal dominant pattern and is caused by a mutation in the NOG gene or GDF5 gene.
Source: GARD

Question: What are the symptoms of Proximal symphalangism ?
Answer: What are the signs and symptoms of Proximal symphalangism? The Human Phenotype Ontology provides the following list of signs and symptoms for Proximal symphalangism. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Camptodactyly of finger 90% Proximal symphalangism (hands) 90% Symphalangism affecting the phalanges of the hand 90% Synostosis of carpal bones 90% Tarsal synostosis 90% Carpal synostosis 75% Abnormality of the metacarpal bones 50% Brachydactyly syndrome 50% Conductive hearing impairment 50% Elbow dislocation 50% Humeroradial synostosis 50% Sensorineural hearing impairment 50% Stapes ankylosis 50% Aplasia/Hypoplasia of the middle phalanges of the hand 7.5% Aplasia/Hypoplasia of the middle phalanges of the toes 7.5% Clinodactyly of the 5th finger 7.5% Finger syndactyly 7.5% Strabismus 7.5% Distal symphalangism (hands) 5% Metacarpophalangeal synostosis 1% Abnormal finger flexion creases - Autosomal dominant inheritance - Pes planus - Proximal/middle symphalangism of 5th finger - Short 5th metacarpal - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
Source: GARD

Question: How to diagnose Proximal symphalangism ?
Answer: Is genetic testing available for Cushing's symphalangism? GeneTests lists the names of laboratories that are performing genetic testing for Cushing's symphalangism. To view the contact information for the clinical laboratories conducting testing, click here. Please note: Most of the laboratories listed through GeneTests do not accept direct contact from patients and their families; therefore, if you are interested in learning more, you will need to work with a health care provider or a genetics professional. Below, we provide a list of online resources that can assist you in locating a genetics professional near you.
Source: GARD