To assess both progression of MONA spectrum disorder and therapeutic success the patients were regularly evaluated clinically in 3 to 6 month intervals. Clinical evaluation comprised an internal, neurological and orthopaedic status as well as a general assessment of neurocognitive function. Additionally, need for oral analgesic therapy was documented. In irregular intervals, depending also on the clinical symptoms, x-rays of hand and feet were taken and a densitometry of the total body, lumbar spine and hip was performed.