Purulent diseases of the extremities and hand

Purulent processes of the lower extremity

The surgical anatomy of purulent foci in the lower extremities is directly related to the arrangement of major muscle groups and neurovascular bundles.

In the thigh, inflammation is most frequently localized within the vastus lateralis muscle (m. vastus lateralis) or rectus femoris muscle (m. rectus femoris). The development of phlegmon in the region of the main vascular bundle and sciatic nerve is also characteristic. Overall, a number of key muscles are identified in this area that may be involved in extensive suppuration: vastus medialis (m. vastus medialis), sartorius (m. sartorius), gracilis (m. gracilis), semimembranosus and semitendinosus (m. semimembranosus, m. semitendinosus), the long head of the biceps femoris (caput longum m. biceps femoris), as well as the adductor magnus and longus muscles (m. adductor magnus et longus).

In the leg, the bony framework is formed by the tibia (tibia) and fibula (fibula). The muscular apparatus is represented by the tibialis anterior (m. tibialis anterior), extensor digitorum longus (m. extensor digitorum longus), peroneus longus and brevis (mm. peroneus longus et brevis), and soleus muscles (m. soleus). Phlegmons of the leg are usually concentrated in the areas where the anterior and posterior tibial vessels course (vasa tibialis anteriora, vasa tibialis posteriora).

Fascial spaces of the hand

The hand has a complex layered structure that determines the pathways through which pus can spread.

• Deep fascial space: located between the deep fascia with interosseous muscles (forming the floor) and the flexor tendons (forming the roof). It contains the deep palmar arterial arch. Pus from here spreads proximally (through the carpal tunnel onto the forearm into Pirogov's space) or distally (through the lumbrical canals to the dorsal aspect of digits II–V and into the 2nd–4th interdigital spaces).
• Superficial fascial space: contains the superficial palmar arch, digital arteries, and median nerve.

There are also isolated fascial compartments on the palm:

1. Medial compartment (hypothenar): located between the own fascia, the anterior surface of the 5th metacarpal bone, and the fascial septum. It contains the muscles of the hypothenar eminence and deep branches of the ulnar neurovascular bundle.
2. Lateral compartment (thenar): bounded medially by the attachment site of the fascia to the 3rd metacarpal bone, and laterally by the lateral surface of the 1st metacarpal bone. The muscles of the thenar eminence lie inside.

The connecting link between the tissues of the palm and forearm is the carpal tunnel, which transmits the median nerve and flexor tendons.

Synovial sheaths and their surgery

Flexor tendons on the palmar surface are surrounded by synovial sheaths. For digits II–IV, these sheaths are completely isolated.

Radial sheath (for the flexor pollicis longus tendon) begins 2–3 cm proximal to the radial styloid process, passes through the carpal tunnel, and terminates at the base of the distal phalanx of the thumb. Ulnar sheath (common flexor sheath) encloses the tendons of digits II–V. In its proximal part, it forms a broad sac at the level of the metacarpophalangeal joints, whereas distally it narrows, reaching the base of the distal phalanx of digit V only.

When tenosynovitis develops, emergency incision is required. Incisions on the proximal and middle phalanges are made as interrupted unilateral or paired linear-lateral incisions. Drainage is performed transversely using a fenestrated tube. It is extremely important to pass the tube strictly above the tendon so as not to injure its mesotendon, which is responsible for blood supply.

In U-shaped (crossed) phlegmon, inflammation spreads from one edge of the hand to the other. Treatment requires massive drainage of three areas simultaneously: the radial bursa (1st digit), the ulnar bursa (5th digit), and the deep fascial space of the forearm (Pirogov-Parona space).

Radical operations and unusual etiologies

The most severe purulent infection of the finger is pandactylitis — the destruction of all its structures. If conservative therapy for fingers II–V fails, radical surgery is indicated — exarticulation of the finger to prevent infection generalization. However, for pandactylitis of the thumb (I), the strategy is different. The surgeon must preserve the finger to the maximum extent possible. Even with a complete loss of flexion and extension function, the thumb provides the vital function of opposition. Its loss critically reduces overall hand functionality and leads to disability.

Opening of phlegmons in the thenar and hypothenar areas is performed taking into account the location of the "danger zone" of the hand, using through-and-through or local drains.

Finally, one should remember deep purulent processes of the neck, which can spread inferiorly. Their frequent cause is foreign bodies (pins, needles, sharp objects) that damage the wall of the cervical esophagus or pharynx. This causes the development of paraesophagitis and paratracheitis, which requires timely removal of the object and anti-inflammatory therapy.

Class and exam questions

What else to study on this topic

• Boundaries and anatomy of the deep Pirogov-Parona space on the forearm
• Location of neurovascular bundles on the thigh and leg
• Topography of the hand's "danger zone" and safe surgical approaches
• Conservative therapy in early stages of pandactylitis
• Anatomy of the cervical esophagus in the context of paraesophagitis

Other topics from the section "CHAPTER 11. SURGICAL INFECTION (PURULENT-INFLAMMATORY DISEASES)"

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.