Penile bone

The males of some mammal species have a bone called the baculum within the penis. Also called the penis bone, penile bone, or os penis, it is an aid to copulation and its size and shape are specific to each species. Animals that have such a bone include rats, dogs, and walruses. These bones are used as fertility charms and objects of curiosity. 

Fig. 12.2a-d. Gunshot penile injury, a X-ray demonstrates the bullet projecting on the right ischiatic bone. b,c Grey-scale ultrasonography (b) and CT (c) show that the bullet is located within the right corpus cavernosum. d Surgical removal of the bullet... 

Most penile metastases originate from the genital apparatus or from the lower urinary tract (Belville and Cohen 1992). In the past, bladder tumor was considered the major source responsible for penile metastases, but a relatively recent revision of the literature pointed out that most secondary penile tumors originate from prostate cancer (Perez et al. 1992). Tumors from different organs, however, can be involved, such as renal, testicle, bowel and rectum, lung, skin and bone malignancies. The reason why penile metastases are rare despite rich penile vascularization remains unexplained. 

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