Rapid destruction of the humeral head due to bone fragility: report of two cases., Yoshikawa Katsuhisa;Tamai Kazuya;Yano Yuichiro;Kato Nakayuki;Akutsu Miwa;Tomizawa Kazuo;Nohara Yutaka, Journal of orthopaedic science : official journal of the Japanese Orthopaedic Association, 19(2), 354-358, Mar. 2014