It is likely the condition refers to a problem referred to as Legg-Calvé-Perthes (LCP) disease. Over 100 years have passed now since Drs. Legg, Calvé, and Perthes first described a hip condition in children now referred to as Legg-Calvé-Perthes (LCP) disease. In those 10 decades, three things have become much clearer: what causes the problem, who is affected, and which treatment approaches work best.
In this condition, the blood supply to the growth center of the hip (the capital femoral epiphysis) is disturbed, causing the bone in this area to die. The blood supply eventually returns, and the bone heals. But in the meantime, there can be severe pain, an obvious limp, loss of motion, and change in function.
How the bone heals determines what problems the condition will cause in later life. Perthes disease may affect both hips. In fact, 10 to 12 percent of the time the condition is bilateral (meaning that it affects both hips). This condition can lead to serious problems in the hip joint later in life.
Seventy-five years ago tuberculosis (TB) was still a problem in this country. Hip problems associated with TB had to be diagnosed and differentiation from Legg-Calvé-Perthes disease. X-rays were used to accomplish this task.
Your family member may have been diagnosed by Dr. Legg himself (or someone who worked or trained with Dr. Legg) to get this diagnosis of Legg hip affliction. At least that’s our best guess given the information you have provided and knowledge of the history of this disease.