A noticeable lump in relation to an<unk> remity may be the first presenting symptom.<unk>  deformities can arise, namely coronal plane deformities around the knees, ankles, shoulders, elbows, and wrists. For example, genu valgum (knock knees), ankle valgus, ulnar bowing and shortening, and radial head subluxation are encountered. The majority of affected individuals have clinically manifest osteochondromas around the knee. Forearm involvement in HMO is considerable. Furthermore, short stature may occur and is generally disproportionate. Such manifestations usually result from disruption of physeal growth especially that osteochondromas typically arise at the metaphyseal ends of long bones in close proximity to the physis. Intra-articular osteochondromas of the hip can induce limitation of range of motion, joint pain and acetabular dysplasia. Likewise joint pain at other locations and neurovascular compression can occur. Furthermore, functional disability in regard to activities of daily living can be a presenting feature. Spinal deformity pain or neurological compromise should arouse suspicion of involvement of the vertebrae. Possible connection to autism Some parents of children with<unk>  have observed autism-like social problems in their children. To explore those observations more deeply, a 2012 study by the Sanford-Burnham Medical Research Institute used a mouse model of<unk>  to observe cognitive function. The findings indicated that the mutant mice endorsed three autistic characteristics: social impairment, impairments in ultrasonic vocalization, and repetitive behavior.
Hereditary multiple exostoses
Inherited patterned lentiginosis
Diffuse idiopathic skeletal hyperostosis
Pycnodysostosis
Familial myxovascular fibromas
Nevoid basal-cell carcinoma syndrome
Gerodermia osteodysplastica
Acrofrontofacionasal dysostosis