Rigi10™ Malleable Penile Prosthesis
Also Known As
Pudendal canal
Definition
Alcock’s canal, also known as the pudendal canal, is a crucial anatomical passageway located in the pelvis. It is formed by a splitting of the obturator fascia, which is the fascia covering the medial aspect of the obturator internus muscle.¹&˒;² It lines the lateral wall of the ischioanal fossa.² The primary purpose of Alcock’s canal is to serve as a conduit for important neurovascular structures. Specifically, the internal pudendal artery, internal pudendal veins, and the pudendal nerve traverse this canal.¹&˒;² The perineal nerve, a significant branch of the pudendal nerve, often arises within Alcock’s canal itself or as the pudendal nerve exits it.¹ Understanding the anatomy of Alcock’s canal is vital as it protects these structures, and its compromise can lead to significant clinical syndromes.¹
Clinical Context
Alcock’s canal is clinically significant primarily due to its relationship with the pudendal nerve and associated vessels.¹ Pudendal nerve entrapment (PNE), also known as Alcock’s canal syndrome, can occur when the pudendal nerve is compressed within this canal.²&˒;&sup4; This compression can lead to a variety of debilitating symptoms, including chronic pelvic pain, perineal pain, pain during sexual intercourse (dyspareunia), and altered sensation in the regions supplied by the pudendal nerve (genitalia, perineum, and anal region).¹ Symptoms may be exacerbated by sitting for long periods.
The pudendal nerve, which traverses Alcock’s canal, is susceptible to injury from various causes, including childbirth (due to stretching or compression during delivery), prolonged cycling, direct trauma to the pelvic region, or surgical procedures in the vicinity.¹ Such injuries can result in loss of sensation, fecal incontinence (due to involvement of the inferior rectal nerve branch), urinary incontinence (due to involvement of branches supplying the external urethral sphincter), and sexual dysfunction, including erectile dysfunction in males and altered arousal or anorgasmia in females.¹
Diagnosis of conditions related to Alcock’s canal, such as PNE, often involves a combination of clinical examination, patient history, nerve conduction studies, and imaging (like MRI) to rule out other causes of pelvic pain. Management can range from conservative measures like physical therapy, lifestyle modifications (e.g., avoiding activities that worsen pain), and pain medications, to more invasive treatments such as pudendal nerve blocks (injecting anesthetic and/or corticosteroids near the nerve, sometimes guided into or near the canal) or surgical decompression of the nerve within Alcock’s canal in refractory cases.¹