Fascial Spaces of the Palm-Fascial Spaces of the Palm and Infection -Pulp Space of the Fingers--Pulp-Space Infection (Felon)

Fascial Spaces of the Palm

Normally, the fascial spaces of the palm are potential spaces filled with loose connective tissue. Their boundaries are important clinically because they may limit the spread of infection in the palm.

The triangular palmar aponeurosis fans out from the lower border of the flexor retinaculum. From its medial border, a fibrous septum passes backward and is attached to the anterior border of the 5th metacarpal bone. Medial to this septum is a fascial compartment containing the three hypothenar muscles; this compartment is unimportant clinically. From the lateral border of the palmar aponeurosis, a second fibrous septum passes obliquely backward to the anterior border of the third metacarpal bone. Usually, the septum passes between the long flexor tendons of the index and middle fingers. This second septum divides the palm into the thenar space, which lies lateral to the septum (and must not be confused with the fascial compartment containing the thenar muscles), and the midpalmar space, which lies medial to the septum. Proximally, the thenar and midpalmar spaces are closed off from the forearm by the walls of the carpal tunnel. Distally, the two spaces are continuous with the appropriate lumbrical canals .

The thenar space contains the first lumbrical muscle and lies posterior to the long flexor tendons to the index finger and in front of the adductor pollicis muscle

The midpalmar space contains the 2nd, 3rd, and 4th lumbrical muscles and lies posterior to the long flexor tendons to the middle, ring, and little fingers. It lies in front of the interossei and the third, fourth, and fifth metacarpal bones.

The lumbrical canal is a potential space surrounding the tendon of each lumbrical muscle and is normally filled with connective tissue. Proximally, it is continuous with one of the palmar spaces

Fascial Spaces of the Palm and Infection

The fascial spaces of the palm are clinically important because they can become infected and distended with pus as a result of the spread of infection in acute suppurative tenosynovitis; rarely, they can become infected after penetrating wounds such as falling on a dirty nail.

Pulp Space of the Fingers

The deep fascia of the pulp of each finger fuses with the periosteum of the terminal phalanx just distal to the insertion of the long flexor tendons and closes off a fascial compartment known as the pulp space . Each pulp space is subdivided by the presence of numerous septa, which pass from the deep fascia to the periosteum. Through the pulp space, which is filled with fat, runs the terminal branch of the digital artery that supplie the diaphysis of the terminal phalanx. The epiphysis of the distal phalanx receives its blood supply proximal to the pulp space.

Pulp-Space Infection (Felon)

The pulp space of the fingers is a closed fascial compartment situated in front of the terminal phalanx of each finger. Infection of such a space is common and serious, occurring most often in the thumb and index finger. Bacteria are usually introduced into the space by pinpricks or sewing needles.

Because each space is subdivided into numerous smaller compartments by fibrous septa, it is easily understood that the accumulation of inflammatory exudate within these compartments causes the pressure in the pulp space to quickly rise. If the infection is left without decompression, infection of the terminal phalanx can occur. In children, the blood supply to the diaphysis of the phalanx passes through the pulp space, and pressure on the blood vessels could result in necrosis of the diaphysis. The proximally located epiphysis of this bone is saved because it receives its arterial supply just proximal to the pulp space.

The close relationship of the proximal end of the pulp space to the digital synovial sheath accounts for the involvement of the sheath in the infectious process when the pulpspace infection has been neglected.

 

Vagina-Supports of the Vagina-Blood Supply-Vulva-Nerve Supply-Vulval Infection-The Vulva and Pregnancy-Urethral Infection-Urethral Injuries-Catheterization

Vagina

The vagina not only is the female genital canal but also serves as the excretory duct for the menstrual flow from the uterus and forms part of the birth canal. This muscular tube extends upward and backward between the vulva and the uterus (see Fig. 8.4). It measures about 3 in. (8 cm) long. The cervix of the uterus pierces its anterior wall. The vaginal orifice in a virgin possesses a thin mucosal fold, called the hymen, which is perforated at its center. The upper half of the vagina lies above the pelvic floor within the pelvis between the bladder anteriorly and the rectum posteriorly; the lower half lies within the perineum between the urethra anteriorly and the anal canal posteriorly
.

Supports of the Vagina

■■ Upper third: Levatores ani muscles and transverse cervical, pubocervical, and sacrocervical ligaments

■■ Middle third: Urogenital diaphragm

■■ Lower third: Perineal body

Blood Supply

Arteries

The vaginal artery, a branch of the internal iliac artery, and the vaginal branch of the uterine artery supply the vagina.

Vulva

The term vulva is the collective name for the female external genitalia and includes the mons pubis, labia majora and minora, the clitoris, the vestibule of the vagina, the vestibular bulb, and the greater vestibular glands.

Blood Supply

Branches of the external and internal pudendal arteries on each side.

The skin of the vulva is drained into the medial group of superficial inguinal nodes.

Lymph Drainage

Medial group of superficial inguinal nodes
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Nerve Supply

The anterior parts of the vulva are supplied by the ilioinguinal nerves and the genital branch of the genitofemoral nerves. The posterior parts of the vulva are supplied by the branches of the perineal nerves and the posterior cutaneous nerves of the thigh.

Vulval Infection

In the region of the vulva, the presence of numerous glands and ducts opening onto the surface makes this area prone to infection. The sebaceous glands of the labia majora, the ducts of the greater vestibular glands, the vagina (with its indirect communication with the peritoneal cavity), the urethra, and the paraurethral glands can all become infected. The vagina itself has no glands and is lined with stratified squamous epithelium. Provided that the pH of its interior is kept low, it is capable of resisting infection to a remarkable degree.

The Vulva and Pregnancy

An important sign in the diagnosis of pregnancy is the appearance of a bluish discoloration of the vulva and vagina as a result of venous congestion. It appears at the 8th to 12th week and increases as the pregnancy progresses.

Urethral Infection

The short length of the female urethra predisposes to ascending infection; consequently, cystitis is more common in females than in males.

Urethral Injuries

Because of the short length of the urethra, injuries are rare. In fractures of the pelvis, the urethra may be damaged by shearing forces as it emerges from the fixed urogenital diaphragm.

Catheterization

Because the female urethra is shorter, wider, and more dilatable, catheterization is much easier than in males. Moreover, the urethra is straight, and only minor resistance is felt as the catheter passes through the urethral sphincter.

Penis-Root of the Penis-Body of the Penis-Blood Supply-Arteries-Veins-Lymph Drainage-Rupture of the Urethra- Erection and Ejaculation after Spinal Cord Injuries -Urethral Infection

Penis

The penis has a fixed root and a body that hangs free

Root of the Penis

The root of the penis is made up of three masses of erectile tissue called the bulb of the penis and the right and left crura of the penis. The bulb is situated in the midline and is attached to the undersurface of the urogenital diaphragm. It is traversed by the urethra and is covered on its outer surface by the bulbospongiosus muscles. Each crus is attached to the side of the pubic arch and is covered on its outer surface by the ischiocavernosus muscle. The bulb is continued forward into the body of the penis and forms the corpus spongiosum. The two crura converge anteriorly and come to lie side by side in the dorsal part of the body of the penis, forming the corpora cavernosa.

 

Body of the Penis

The body of the penis is essentially composed of three cylinders of erectile tissue enclosed in a tubular sheath of fascia (Buck’s fascia). The erectile tissue is made up of two dorsally placed corpora cavernosa and a single corpus spongiosum applied to their ventral surface. At its distal extremity, the corpus spongiosum expands to form the glans penis, which covers the distal ends of the corpora cavernosa. On the tip of the glans penis is the slitlike orifice of the urethra, called the external urethral meatus.

The prepuce or foreskin is a hoodlike fold of skin that covers the glans. It is connected to the glans just below the urethral orifice by a fold called the frenulum.

The body of the penis is supported by two condensations of deep fascia that extend downward from the linea alba and symphysis pubis to be attached to the fascia of the penis.

 

Blood Supply

Arteries

The corpora cavernosa are supplied by the deep arteries of the penis; the corpus spongiosum is supplied by the artery of the bulb. In addition, there is the dorsal artery of the penis. All the above arteries are branches of the internal pudendal artery.

 

Veins

The veins drain into the internal pudendal veins.

Lymph Drainage

The skin of the penis is drained into the medial group of superficial inguinal nodes. The deep structures of the penis are drained into the internal iliac nodes

Nerve Supply

The nerve supply is from the pudendal nerve and the pelvic plexuses.

Rupture of the Urethra

Rupture of the urethra may complicate a severe blow on the perineum. The common site of rupture is within the bulb of the penis, just below the perineal membrane. The urine extravasates into the superficial perineal pouch and then passes forward over the scrotum beneath the membranous layer of the superficial fascia,. If the membranous part of the urethra is ruptured, urine escapes into the deep perineal pouch and can extravasate upward around the prostate and bladder or downward into the superficial perineal pouch.

  Erection and Ejaculation after Spinal Cord Injuries

Erection of the penis is controlled by the parasympathetic nerves that originate from the 2nd, 3rd, and 4th sacral segments of the spinal cord. Bilateral damage to the reticulospinal nerve tracts in the spinal cord will result in loss of erection. Later, when the effects of spinal shock have disappeared, spontaneous or reflex erection may occur if the sacral segments of the spinal cord are intact.

Ejaculation is controlled by sympathetic nerves that originate in the 1st and 2nd lumbar segments of the spinal cord. As in the case of erection, severe bilateral damage to the spinal cord results in loss of ejaculation. Later, reflex ejaculation may be possible in patients with spinal cord transections in the thoracic or cervical regions.

Urethral Infection

The most dependent part of the male urethra is that which lies within the bulb. Here, it is subject to chronic inflammation and stricture formation.

The many glands that open into the urethra—including those of the prostate, the bulbourethral glands, and many small penile urethral glands—are commonly the site of chronic gonococcal infection.

Injuries to the penis may occur as the result of blunt trauma, penetrating trauma, or strangulation. Amputation of the entire penis should be repaired by anastomosis using microsurgical techniques to restore continuity of the main blood vessels.

Uterine Tube-Uterine TubeFunction-Blood Supply-The Uterine Tube as a Conduit for Infection-Pelvic Inflammatory Disease-Ectopic Pregnancy- Tubal Ligation-

Uterine Tube

The two uterine tubes are each about 4 in. (10 cm) long and lie in the upper border of the broad ligament . Each connects the peritoneal cavity in the region of the ovary with the cavity of the uterus. The uterine tube is divided into four parts:

1. The infundibulum is the funnel-shaped lateral end that projects beyond the broad ligament and overlies the ovary. The free edge of the funnel has several fingerlike processes, known as fimbriae, which are draped over the ovary .

2. The ampulla is the widest part of the tube.

3. The isthmus is the narrowest part of the tube and lies just lateral to the uterus .

4. The intramural part is the segment that pierces the uterine wall .

Function

The uterine tube receives the ovum from the ovary and provides a site where fertilization of the ovum can take place (usually in the ampulla). It provides nourishment for the fertilized ovum and transports it to the cavity of the uterus. The tube serves as a conduit along which the spermatozoa travel to reach the ovum.

Blood Supply

Arteries

The uterine artery from the internal iliac artery and the ovarian artery from the abdominal aorta .

Veins

The veins correspond to the arteries.

Lymph Drainage

The internal iliac and para-aortic nodes.

Nerve Supply

Sympathetic and parasympathetic nerves from the inferior hypogastric plexuses

The Uterine Tube as a Conduit for Infection

The uterine tube lies in the upper free border of the broad ligament and is a direct route of communication from the vulva through the vagina and uterine cavity to the peritoneal cavity.

Pelvic Inflammatory Disease

The pathogenic organism(s) enter the body through sexual contact and ascend through the uterus and enter the uterine tubes. Salpingitis may follow, with leakage of pus into the peritoneal cavity, causing pelvic peritonitis. A pelvic abscess usually follows, or the infection spreads farther, causing general peritonitis.

Ectopic Pregnancy

Implantation and growth of a fertilized ovum may occur outside the uterine cavity in the wall of the uterine tube. This is a variety of ectopic pregnancy. There being no decidua formation in the tube, the eroding action of the trophoblast quickly destroys the wall of the tube. Tubal abortion or rupture of the tube, with the effusion of a large quantity of blood into the peritoneal cavity, is the common result.

The blood pours down into the rectouterine pouch (pouch of Douglas) or into the uterovesical pouch. The blood may quickly ascend into the general peritoneal cavity, giving rise to severe abdominal pain, tenderness, and guarding. Irritation of the subdiaphragmatic peritoneum (supplied by phrenic nerves C3, 4, and 5) may give rise to referred pain to the shoulder skin (supraclavicular nerves C3 and 4).

Tubal Ligation
Ligation and division of the uterine tubes is a method of obtaining permanent birth control and is usually restricted to women who already have children. The ova that are discharged from the ovarian follicles degenerate in the tube proximal to the obstruction. If, later, the woman wishes to have an additional child, restoration of the continuity of the uterine tubes can be attempted, and, in about 20% of women, fertilization occurs.