Pus in the hands and feet
From Primary Surgery
The general method for an infected hand
A badly infected hand can be a real disaster. Some infections arise spontaneously, others follow quite minor injuries, or even a seemingly trivial scratch. They are particularly common in leprosy patients (30.4, 30.6). The best prevention is an early and thorough toilet of all hand wounds. If you do this early, it is quite a minor procedure. The great danger of late or inadequate treatment is a stiff finger (75.2), which is a great disability, and may need amputation.
If you treat a patient early enough, antibiotics may be effective, and may prevent a serious lesion spreading. Some hand surgeons make little use of them, and they are certainly much less important than a careful wound toilet and early drainage.
There are many spaces in the hand where pus can collect, each with its own signs and incisions. These spaces are not rigidly defined; some run into one another, and more than one may be infected at the same time, as in Fig. 8-5, so don't be dismayed by the apparent complexity of pus in the hand. The common places for it to collect are in the pulp spaces of the fingers (8.5), and in the web spaces (8.7). Even after pus has formed, he should recover completely[md]if you treat him correctly, and provided that his tendon sheaths have not been involved.
PUS IN THE HAND IS COMMON AND SERIOUS! DON'T BE BOTHERED BY THE NUMBER OF INCISIONS! One difficulty is knowing when to incise an infected hand. Pus is so tightly trapped in the spaces of the hand that you cannot use fluctuation as a sign that it is present. A good rule to remember is that, if his hand prevented him sleeping the previous night, it needs incising.
When you operate: (1) Don't cut his digital nerves[md]remember that they run on the radial and ulnar aspects of his fingers just anterior to the tips of his finger creases, as in D, Fig. 8-6. (2) Don't cut through a more superficial abscess into his flexor sheaths underneath, or you may infect them. These are in the greatest danger where they are nearest to the surface, under the flexor creases of his fingers. So don't incise the palmar surface of a finger proximal to its distal flexion crease, unless you are deliberately draining an infected tendon sheath. (3) When you drain pus, be sure to remove the granulation tissue that surrounds it, so that the wall of the abscess is clean, and antibiotic containing blood can enter it. (4) Use a bloodless field whenever you can, so that you can see the anatomy clearly.
DON'T WAIT FOR FLUCTUATION IF PAIN KEPT HIM AWAKE LAST NIGHT, INCISE HIS HAND USE A TOURNIQUET Fig. 8-1 THE MANY PLACES WHERE PUS CAN COLLECT IN THE HAND. There are also three which are not shown here: these are the web spaces in Fig. 8-5. After Farquharson's Textbook of Operative Surgery', edited by Rintoul RF, Fig. 3O2 (Churchill Livingstone): and Campbell's Operative Orthopaedics', edited by Edmondsen AS and Crenshaw AH[md]the Chapter on Hand Infections' by Lee Milford, Fig. 3-357, (CV Mosby Company). Both with kind permission.
THE GENERAL METHOD [s8]FOR HAND (AND FOOT) INFECTIONS If the patient has leprosy, see Sections 30.4 and 30.6.
WHERE IS THE PUS? Feel carefully for the point of greatest tenderness by probing with a matchstick.
If his terminal phalanx is infected, consult Figure 8-2.
If his whole hand is swollen like an inflated rubber glove, the pus is probably in his mid palmar space, or in a flexor tendon sheath, especially if he cannot move his little and ring fingers.
If the greatest swelling is over the web of his thumb, he probably has pus in his thenar space, especially if his index finger is held flexed, and he cannot move it or his thumb.
If: (1) his whole finger is swollen and tender, (2) there is no obvious sign of the pus pointing, and (3) any movement of the finger is exquisitely painful, he probably has a tendon sheath infection.
If all his fingers, especially the fifth, are held semi- flexed and rigid, suspect that the tendon sheaths in his ulnar bursa are infected.
If he has lymphangitis, lymphadenitis, and fever, his infection is spreading. If pus is present, incise his hand under antibiotic cover, and continue after his temperature and pulse have become normal.
CAUTION ! Pus is much more likely to be present on the palmar surface than on the dorsum, so don't be misled by swelling on the back of his hand. The commonest cause of a swollen dorsum is a web space infection.
SPECIAL TESTS. Test his urine for sugar[md]diabetes may present as a septic infection.
TREATMENT [s7]FOR HAND INFECTIONS RAISE HIS HAND to make him more comfortable and promote healing. In less severe infections, raise his arm in the St. John's sling. In more severe ones, such as a tendon sheath infection, put him to bed and raise his hand in a roller towel: both are shown in Fig. 75-1.
ANTIBIOTICS are usually unnecessary, but if his infection is spreading (see above) give him penicillin in the dose for a severe infection. If antibiotic resistance is likely, for example if he is working in a hospital, or your local strains are apt not to respond to penicillin, give him chloramphenicol, erythromycin, or, if you can afford it, cloxacillin.
Don't forget to give him an analgesic.
INCISING [s7]HAND INFECTIONS SHOULD YOU INCISE IT? Don't try to treat an infected hand by aspiration only. Base your decision to incise it on: (1) The presence of acute local tenderness. This shows that pus is present and where it is pointing. (2) The length of his history[md]if symptoms are becoming worse after 48 hours, his hand probably needs incising. (3) The severity of the swelling. (4) The nature of his pain. If throbbing pain kept him awake last night, incise his hand.
ANAESTHESIA must be adequate. For any but the most minor infection, avoid local infiltration close to the infection, because this will only spread it and increase the swelling.
If the infection is in the distal two thirds of his finger or thumb you can use a finger block without adrenalin (A 6.21).
For all other hand infections, use an axillary block (A 6.18), or an intravenous forearm block (A 6.19), or ketamine (A 8.2), or general anaesthesia.
A TOURNIQUET is essential in all but the most superficial infections, because a bloodless field makes the operation easier (3.9). Don't exsanguinate his arm with an Esmarch bandage, because it may spread the infection.
If the pus is in the distal segment, wrap a rubber catheter twice round the base of his finger or thumb, and clamp it with a heavy haemostat.
If the pus is anywhere else, apply a pneumatic tourniquet, or an Esmarch bandage properly applied as a tourniquet (3.9).
EQUIPMENT. Use a small scalpel, fine pointed scissors, skin hooks, fine dissecting forceps, and if necessary Volkmann's spoon.
ASSISTANT. If he has a major infection, you must have an assistant scrubbed up to hold the retractors.
INCISING, DESLOUGHING AND DRAINING. Clean his skin with antiseptic. Incise where pus points, and don't adhere too slavishly to standard incisions, which are described later. We have numbered the incisions that you will need for major hand infections from 1 to 12. Most of them are shown on Fig. 8-6.
When you extend an incision, do so in a skin crease. If necessary jump from one crease to another by making a Z-shaped incision. Remove skin that is already dead. If necessary, extend an incision to explore the whole abscess cavity, and remove deeper dead tissues.
If more than one space is infected, adapt your incision(s) accordingly. For example, if his mid-palmar space, several web spaces and his tendon sheaths are infected, you may need to make several incisions like those in Fig. 8-5.
As soon as you are through his skin, insert a haemostat, open it, and explore the abscess cavity (Hilton's method). Culture the pus.
If there are no vulnerable structures such as periosteum, nerves or tendon sheaths, nearby, scrape away the lining of his abscess with curette or a swab. If there are vulnerable structures nearby, be more cautious, and only use a swab.
Drain the abscess by putting a piece of rubber glove into it. Or, leave a piece of vaseline gauze between the wound edges.
CAUTION ! (1) Don't cut his nerves, see Fig. 8-6. (a) His digital nerves run near the anterolateral margins of his fingers. So either cut near the middle of the palmar surfaces of his fingers, or on their lateral surfaces fairly posteriorly at the apex of his finger creases. (b) The muscular branch of his median nerve comes off the main trunk just distal to the tuberosity of his scaphoid and curves round into his thenar muscles. (2) Don't pack the wound tightly.
TO CONTROL BLEEDING remove the tourniquet, raise his arm and press firmly on the wound for 5 to 10 minutes without interruption.
POSTOPERATIVELY, be sure to elevate his hand, until pain and swelling subside[md]this is an important way of reducing stiffness. Rapid resolution of inflammatory oedema is more important than early movement in reducing stiffness. Wrap the wound with plenty of gauze, and use the dressings to splint it in the position of safety (75.8). Leave them on for several days, unless the wound becomes painful, or swells, or there is much discharge. When you change the dressings, use careful aseptic precautions, so as to avoid secondary infection. If they stick, soak them off in saline, and then gently remove them.
If the infection was extensive, check 2 to 4 days later for residual infection or necrotic tissue which may need treatment.
CAUTION ! Start active movements as soon as pain has subsided.
RAISE AN INFECTED HAND STIFF FINGERS RESULT IN POOR FUNCTION
Subcutaneous hand infections
A patient's skin and subcutaneous tissue can be infected anywhere in his hand. Pulp infections and paronychia are merely subcutaneous infections at the tip of a finger. If there is pus under the keratinized layers of his epidermis, strip these off, and see if you can find the hole through which it has tracked from a deeper abscess underneath. An abscess near the surface may communicate with pus deep inside his hand through a narrow opening. Pus like this forms a collar-stud abscess' as shown in Fig. 8-1. So, whenever you find a superficial abscess, look for the passage which might be joining it to a deeper one.
Carbuncles (5.4) may form in the hair follicles on the back of the fingers and hand. Antibiotics will not cure them, so deslough them.
DON'T BE MISLED BY A COLLAR-STUD ABSCESS Fig. 8-2 INFECTION AROUND THE NAIL. A patient can have pus on one side of his nail, either superficial (E), or deep (G). It may track all round his nail (A, and B) so that the proximal part of his nail needs excising (I to L). Avoid incising the ball of his finger (M) unless pus is already pointing there. N, and O, if infection is already present in several of the compartments of his pulp, you will have to make a lateral incision. Keep your incision away from his palmar skin, and not more than 3 mm from the edge of his nail. Note: In N, don't cut the end of his finger off; this is a schematic cross-section only! A, and B, after Flatt AB, Functional Anatomy', Fig. 14.2 with kind permission.
Infections of the apical finger space
The apical space lies between the distal part of a patient's nail and the bone of his distal phalanx. It may be infected when a splinter runs under his nail. His finger is painful, but there is little swelling. Tenderness is greatest at or just under the free edge of his nail. Cut a small V' out of the edge of the nail over the point of greatest tenderness, as in C, and D, Fig. 8-2. Remove the full thickness of the skin as a small wedge, and drain the pus.
Paronychia
Paronychia is an infection beside or proximal to a patient's nail. Pus may track round it, as in A and B, Fig. 8-2; either superficial to his nail as in E, and F, or deep to it as in G, and H. Early antibiotic treatment may abort the infection, but you usually have to drain pus.
PARONYCHIA For the general method for a hand infection, see Section 8.1.
If the pus is superficial to a patient's nail on one side only, incise it by angling the knife away from his nail to avoid cutting his nail bed, as in E, and F, Fig. 8-2.
If the pus lies under one corner of his nail, reflect a little flap and remove that corner only, as in G, and H.
If pus has tracked to the other side of his finger under his nail, make a second incision there, retract the flap, excise the proximal one third of his nail, pack the wound open and drain it, as in I, to L, in Fig. 8-2.
If the infection fails to resolve, or his nail becomes indurated and red, suspect a fungus infection, and examine scrapings microscopically. If you find fungi, remove his nail and apply wet dressings, or a topical antifungal agent, such as Castellani's paint or gentian violet.
Infection of the pulp space of the finger
This is the commonest hand infection[md]pus more often gathers in the finger tips than anywhere else in the hand.
The pulp of a finger is divided into many small fatty compartments by strands of fibrous tissue which run from the skin to the periosteum of the terminal phalanx. A sheet of fibrous tissue runs from the distal flexor crease to the periosteum, and so separates the pulp space from the rest of the finger. There is little room for swelling, so that infection causes a throbbing pain early. Pus from a patient's pulp can track: (1) through to the skin outside, or (2) through the periosteum, causing osteomyelitis of his distal phalanx. Its epiphysis is supplied by a separate artery, so this usually survives the infection.
PULP INFECTION For the general method for hand infections, see Section 8.1. Tenderness is maximal over the ball of the patient's pulp.
If the abscess is in his distal pulp, and is already pointing to its centre, drain it by making a cross-shaped incision, or by removing a small circular or elliptical segment of skin over the abscess, as in B, to E, Fig. 8-3. The incision will heal to leave a small punctate scar.
If the abscess is deep, is not pointing, and appears to extend into several compartments, make a J-shaped lateral longitudinal incision close to the bone, and not more than 3 mm in a palmar direction from the free edge of his nail. Keep your knife away from his palmar skin, as in N, and O, Fig. 8-2, and avoid the tip of his finger. Remove pus and slough, and lightly pack the wound with gauze. Don't suture the incision. Change the dressing after two days.
If the infection has been neglected, so that the whole terminal segment of his finger is swollen, continue the incision over the end of his finger and round to the other side. Divide the vertical septa and let the wound gape open. Dress it as above.
CAUTION ! (1) Don't incise the tips of his fingers, or the palmar surfaces of his distal phalanges, unless pus is already pointing there, because pressure on the scar may be painful. (2) Any incision, other than those described, is likely to be painful, especially if you carry it towards the palmar surface. (3) Don't damage his periosteum. (4) Check for a collar-stud abscess (easily seen if you have used a tourniquet to give you a bloodless field).
DIFFICULTIES. [f41]If his infected FINGER CONTINUES TO DISCHARGE for some weeks, suspect osteomyelitis (8.16D). X- ray it. When X-rays show that the sequestrum has separated, remove it. If he is a child, his distal phalanx will regenerate under its periosteum. If he is an adult, he will be left with an ugly curved nail and a short terminal phalanx.
Fig. 8-3 PULP INFECTIONS. A, a neglected pulp infection. Much of the patient's finger tip is already destroyed, and pus is starting to discharge spontaneously. B, [f10]if pus is already pointing, [f11]make a cross-shaped incision. C, swab away the pus. D, remove any dead skin. E, open up the infected pulp compartment. If it is not pointing and several spaces are infected, open up his finger tip from the side as in N in the previous figure.
Infections of the spaces over the volar surfaces of the middle and proximal phalanges
Pus sometimes collects on the volar surfaces of a patient's fingers, superficial to his tendon sheaths, as shown in A, Fig. 8-1. The spaces where it forms are separated from one another by the fibrous septa which run dorsally from the flexor creases of his fingers. The proximal space in each finger communicates with the web spaces in his palm. Pus may collect under his epidermis or under his deep fascia, and is less likely to remain localized than in a terminal phalanx.
He holds his swollen, tender, indurated finger semi-flexed. Trying to straighten it is acutely painful. Distinguishing an infection of these spaces from localized infection of a tendon sheath may be so difficult that you will not know which he has, until you have explored his hand.
Drain pus from a volar space through a transverse incision over the point of greatest tenderness. Take great care not cut into the tendon sheath underneath it or to damage his digital vessels or nerves (G, 8-6). Use a tourniquet to give you a bloodless field.
DON'T OPEN A TENDON SHEATH OR A JOINT UNLESS IT IS INFECTED
Web space infections
Three spaces, filled with loose fat, lie between the bases of a patient's fingers in the distal part of his palm. They lie just proximal to his deep transverse ligaments, near his MP joints. Pus more often gathers here than anywhere else in his hand, except in the pulp spaces of his finger tips. It mostly gathers near the palmar surface, but if it is not drained, it may track: (1) posteriorly towards the dorsum, (2) along a lumbrical canal into his middle palmar space, (3) across the front of a finger into a neighbouring web space, or (4) distally into his finger.
Pain and swelling may be so great that he comes for treatment before much pus has formed. The back of his hand is swollen, as in D, Fig. 8-5. If infection is severe, the fingers on either side of the web separate[md]a very useful sign. The point of maximum tenderness is on the palmar surface of the web, and may extend a short way into his palm. Although you may suspect a web space infection, you may find it difficult to exclude an infected tendon sheath.
WEB SPACE INFECTION. For the general method for an infected hand, see Section 8.1.
Make a V-shaped incision between the patient's fingers, as in incision (1), in Figs. 8-5 and 8-6.
If pus is pointing into his palm, pass a probe proximally from the incision you have just made in his web space up into his palm. Its tip should underlie the place where the pus is pointing. Make a second incision there. Scrape the walls of the abscess cavity free from granulation tissue. If necessary, divide some strands of his palmar fascia.
Infection of the superficial palmar space
When pus collects in the superficial palmar spaces of a patient's hand, it does so under his palmar fascia. Sometimes, it tracks superficially and forms a collar-stud abscess under the superficial layers of his epidermis, as in B, Fig. 8-1.
SUPERFICIAL PALMAR SPACE. For the general method for a hand infection, see Section 8.1.
If you can see pus under the patient's epidermis, remove it and look for a track leading deeper into his hand.
If you cannot see any pus, make a small transverse incision over the point of maximum tenderness, in the line of the nearest skin crease (not illustrated). Probe the abscess cavity. If you find an opening leading to a deeper collection of pus, enlarge it. Scrape infected granulations from the wall of the cavity.
Fig. 8-4 THE THENAR (radial) AND THE MIDDLE PALMAR SPACES lie deep to a patient's flexor tendons, between them and the fascia covering his metacarpals and interossei (see also Fig. 8-1). They communicate with his lumbrical canals. Incise his middle palmar space in the middle third of his distal (or proximal) palmar crease (incision 2), or along the ulnar border of his hand (incision 3). Incise his thenar space in the web between his thumb and his index finger (incision 4), or along his thenar crease in his palm (incision 5). Beware of the motor branch of his median nerve!
Infection of the middle palmar space
This is the most important space in the hand, and is frequently infected in leprosy patients (30.4). It lies deep to a patient's flexor tendons and lumbricals, and between them and the fascia covering his interossei and metacarpals. It is separated from his thenar space by a fibrous septum which extends from his middle metacarpal towards his palmar fascia. Infection reaches this space from a lumbrical canal, or from an infected tendon sheath.
His hand is so grossly swollen that it looks like a blown-up rubber glove. The normal hollow of his palm is obliterated, and the dorsum of his hand is swollen. He cannot move his middle or ring fingers. His interossei are surrounded by pus and paralysed, so that if you ask him to hold a piece of paper between his extended fingers he cannot do so.
The middle palmar space communicates through the carpal tunnel with a space deep to the flexor tendons in the forearm (the space of Parona). If there is pus there you may be able to detect fluctuation between it and the pus in his palm.
MIDDLE PALMAR SPACE. For the general method for a hand infection, see Section 8.1. Always use a tourniquet.
Make a transverse incision (incision 2) in the middle third of the patient's distal or proximal palmar creases or wherever fluctuation is maximal. Enter his middle palmar space on either side of the flexor tendon of his ring finger. Or, enter it through an incision along the ulnar border of his hand, passing between his 5th metacarpal and his hypothenar muscles (incision 3). As soon as you are through his skin, use blunt dissection (Hilton's method) in the line of his tendons and nerves. See also under ulnar bursa' (8.13).
CAUTION ! (1) Don't make your initial incision deeper than his palmar fascia. Push a blunt instrument through it to free the pus underneath. You can then see clearly to open up the space more by a combination of sharp and gentle blunt dissection. (2) Don't cut his digital nerves or vessels, his flexor tendons, or his lumbrical muscles.
If there is pus in the space of Parona, drain it through a longitudinal incision (incision 6) on one side of his palmaris longus tendon (absent in 5% of people), taking care not to injure his median and ulnar nerves or his radial and ulnar vessels.
Fig. 8-5 A SEVERE HAND INFECTION. This started as a web infection which spread to the patient's middle palmar space. A, shows the standard site of the incisions for a middle palmar space infection (incisions 2 and 3), and B that for web space infections (incisions 1). In this patient these incisions had to be modified. C, shows the callosity through which infection entered. Although the back of his hand was swollen (D) it was not incised, because the swelling was due to secondary inflammatory oedema only. E, pus was found in his distal palm, his three web spaces, and his flexor sheaths. The spaces were drained and necrotic tissue was excised. F, eight days after the incision the web spaces have been grafted. After Campbell's Operative Orthopaedics', edited by AS Edmondson and AH Crenshaw[md]the Chapter on Hand infections' by Lee Milford, Figs. 3-355 and 3- 356. CV Mosby, with kind permission.
Infection of the thenar space of the hand
A patient's thenar space (B, and C, Fig. 8-1) is sometimes infected by a penetrating wound. It lies underneath his palmar fascia, and is bounded dorsally by the transverse head of his adductor pollicis. On its ulnar side a fibrous septum divides it from his middle palmar space.
His thenar eminence is grossly swollen, and his thumb is abducted.
THENAR SPACE. For the general method for a hand infection, see Section 8.1.
Drain the patient's thenar space over the point of greatest tenderness through a curved incision in the web between his thumb and index finger, parallel to the border of his first dorsal interosseous muscle, on the dorsal edge of his hand (incision 4). Or, drain it in an incision along his thenar crease in his palm (incision 5). Insert a haemostat deep into the abscess, and open it. You will usually find that it is walled off from the muscles of his thumb.
CAUTION ! Remember the course of the sensory and motor branches of his median nerve which lies within his thenar muscles. These are in less danger from incision (4) than from incision (5).
Infections on the dorsum of the hand and fingers
Infection almost anywhere in a patient's hand makes its back swell, but pus seldom collects there. On the rare occasions when it does collect on the dorsum, it is usually subcutaneous, and only occasionally in the subaponeurotic space under his extensor tendons (B, Fig. 8-1). If localized tenderness persists for more than 48 hours, don't wait for fluctuation. Drain it through a longitudinal incision over the point of greatest tenderness.
THE COMMONEST CAUSE OF SWELLING ON THE DORSUM IS INFECTION IN THE PALM Fig. 8-6 INCISIONS FOR HAND INFECTIONS. Incisions for the finger tips are shown in Figs. 8-2 and 8-3. Some infections don't have fixed incisions (the volar surfaces of the proximal and middle phalanges, the superficial palmar space, and the dorsum of the hand), so these are not illustrated. A, to D, the remaining incisions for more serious hand infections, have been numbered, and most of them are shown here.
Incisions 1 for web space infections. Alternative incisions 2 and 3 for a middle palmar space infection. Alternative incisions 4 and 5 for a thenar space infection. Incision 6 for pus in the space of Parona (proximal to the flexor retinaculum and deep to the flexor tendons).
There are several alternative incisions for tendon sheaths: The lateral ones 7. The transverse palmar ones 8 (shown in Fig. 8-7). The zig-zag palmar ones 9; 9a the first part, and 9b the second part if necessary. Incisions 7 and 8 are for less severe infections, and incisions 9 for more severe ones.
Incision 10 divides the flexor retinaculum. Incisions 11 or 12 drain the radial bursa.
E, the tendon sheaths, the radial and ulnar bursae, the lumbrical muscles, and the flexor retinaculum.
F, the incision for dividing the flexor retinaculum (10). On the ulnar side of the retinaculum the palpable landmarks are the pisiform and the hook of the hamate. On the radial side you can feel the tubercle of the scaphoid and, more deeply, the tuberosity of the trapezium (see also Fig. 27-14a).
G, a cross section of the finger. The digital nerves are at the edges' of the palmar surfaces, so don't incise there. Either incise towards the middle of the palmar surfaces or laterally towards the dorsum as shown by the arrows. E, and F, after Grant's Method of Anatomy', (9th edn. 1975 edited by JV Basmajian). Williams and Wilkins, with kind permission.
Infections of the flexor tendon sheaths of the hand
The sheaths of a patient's flexor tendons come nearest to his skin as they pass under the flexor creases of his fingers. It is here, and particularly over his distal flexor crease, that they are most often punctured and infected. They can also be infected by spread from a pulp infection. The sheaths of his little finger and thumb (and occasionally those of his other fingers also) extend proximally into his palm, and so provide a path through which infection can spread there. If an infected tendon sheath bursts, it does so into the middle palmar space, through one of the lumbrical canals.
There are problems: (1) An infected tendon may later stick to its sheath and make a finger stiff. (2) If pressure inside a sheath exceeds that in its vessels, which can occur if drainage is delayed, the tendon will become ischaemic and slough.
If infection is localized or one area is maximally infected, staphylococci are usually causing it. Only one segment of his finger is swollen, so that distinguishing a localized tendon sheath infection of this kind from an infection of one of his middle palmar and thenar spaces can be difficult (8.9).
If infection is fulminating, streptococci are usually responsible, and his whole finger is swollen, sausage shaped and acutely tender, without becoming red. The swelling extends into his distal palm. He holds his finger partly flexed, and cannot bend it, except perhaps for a little movement at its MP joint.
The danger when you open a tendon sheath is that you may cut a patient's digital nerves. So study where these run in the cross-section of the finger shown in G, Fig 8-6. Either approach a tendon laterally, well towards the dorsum, or from the palm. The danger area is the palmolateral' region. The other nerve which is in danger is the motor branch of his median nerve as it curves round the distal end of his flexor retinaculum and the tubercle of his trapezium.
Adjust your incisions to the severity of the infection. You can approach an infected tendon sheath: (a) Along the side of a finger towards the dorsum (incision 7). (b) Through several transverse incisions on his palm (incisions 8, see Fig. 8-7). (c) By making zig-zag cuts on his palm (incisions 9); these give the best exposure, but take longer to heal. Incisions 7 and 8 are for less severe infections.
Tendon sheath infections are a common complication of the anaesthetic hands of leprosy (30.4), which allow a patient to neglect an infection until it is so advanced that it has destroyed his tendon sheaths.
Fig. 8-7 INFECTIONS OF THE TENDON SHEATHS. A, lateral incisions for opening an infected tendon sheath (incision 7). B, the anatomy of a tendon sheath, to show the fibrous pulleys opposite the shafts of the phalanges. C, the surface markings of the tendon sheaths. D, transverse incisions for draining tendon sheaths (incisions 8). E, opening the distal cul-de-sac (incision 8a). F, irrigating a tendon sheath. E, and F, after Farquharson's Textbook of Operative Surgery', edited by RF Rintoul, Figs. 317 and 318. Churchill Livingstone, with kind permission.
FLEXOR SHEATH INFECTIONS For the general method for a hand infection, see Section 8.1.
EXPOSING [s7]THE TENDON SHEATHS Start by opening the soft tissue over the involved segment through a small lateral incision (incision 7). Examine the synovial sheath. If there is any sign of infection (redness, or thickening) open the sheath itself and look carefully at the fluid. If there is much fluid, it is probably infected; if it is even a little cloudy, it is certainly infected.
If a sheath is infected, make several incisions over the patient's finger(s) and distal palm (incisions 8a, and 8b). Hold the sheath open with hooks and retractors. Using a stiff catheter, syringe the sheath with saline or sterile water (F).
If a sheath is infected in his palm (as is usual with his little finger and thumb), make a further incision (incision 8c) at his wrist, and repeat the irrigation, inserting the catheter through the palmar incision.
If his tendon sheaths are grossly infected, operate urgently. Open the sheath by a zig-zag incision on the volar surface of his finger as in Fig. 8-6. Do this in two stages. First cut along the solid lines (9a), then, if necessary join up these incisions by cutting along the dotted ones (9b). Cut the flaps in the palm larger than those in the fingers, and make them follow his skin creases where possible. Cut through his skin and open the tissues with scissors. Leave bridges of the sheath over the joints to act as pulleys to prevent the tendons prolapsing.
CAUTION ! Don't take the incisions laterally where they may injure his neurovascular bundles.
Wash out the pus with saline. Don't close the incision; the flaps will heal by granulation to leave a linear scar.
If a tendon has become a grey slough, extend the incision, withdraw the dead part into the wound, and excise it. Preserve its sheath and pulley. Allow the wound to heal. If his hand settles well it may be possible to insert a tendon graft later. This will only be worthwhile if the joints of his fingers are mobile. So, as soon as the swelling is starting to settle, he needs intensive physiotherapy, both by himself and a by a physiotherapist[md]this is vital! If his finger remains stiff, try to persuade him that it should be amputated. A stiff finger can be a severe handicap.
If a tendon and its sheath are extensively disorganized, consider amputating his finger. If you don't do so: (1), infection may spread and cause further damage, (2) when his finger heals, it will be stiff, and cause considerable disability by impairing the grip of his other fingers. It may be better amputated. But a stiff thumb is much better than no thumb, so retain it.
If his palm is seriously infected, divide his flexor retinaculum to free his tendons. Either: (a) Approach this through a longitudinal incision 1 cm to the ulnar side of his scaphoid tubercle. Make a 5 cm longitudinal incision over his retinaculum. Keep to the ulnar side of his median nerve and its ulnar branch (incision 10) Or, (b) use the approach shown for the ulnar bursa (incision 3). Both are shown in Fig. 8-6.
AN UNNECESSARY INCISION IS BETTER THAN A LOST FINGER
Infection of ulnar bursa of the hand
Infection of the ulnar bursa is the most serious hand infection, because it contains all the flexor tendons of a patient's fingers. His whole hand is oedematous, his palm is moderately swollen, and there may a fullness immediately above his flexor retinaculum. His flexed fingers resist extension, particularly his little one, and least of all his index.
The radial and ulnar bursa sometimes communicate with one another. So if one of them has been infected, infection may follow in the other a day or two later.
INFECTION OF THE ULNAR BURSA. For the general method for a hand infection, see Section 8.1.
Open the tendon sheath of the patient's little finger with palmar flaps, using incisions 9a and if necessary 9b.
Incise his skin and deep fascia over the antero-medial side of his fifth metacarpal, using incision 3. Separate his abductor and flexor digiti minimi muscles from the bone. Retract them forwards and you will see his opponens digiti minimi muscle. Divide this close to its attachment to his flexor retinaculum. Divide his flexor retinaculum deep to opponens digiti minimi[md]you will see his bulging ulnar bursa. Wash this out, as for a tendon sheath infection (8.12)
You can also drain his middle palmar space through this incision, as in Section 8.9.
Infection of the radial bursa of the hand
A patient's radial bursa is a continuation of the tendon sheath of his flexor pollicis longus, so that any infection inevitably involves both of them. The distal phalanx of his thumb is flexed and rigid. He cannot extend it, although he can extend his other fingers normally. His hand is tender over the sheath of flexor pollicis longus, and you may be able to feel a swelling above his flexor retinaculum. If treatment is delayed, infection may spread to his ulnar bursa, or the tendon of his flexor pollicis longus may slough.
INFECTION OF THE RADIAL BURSA Incise the patient's radial bursa through incision 11 along the proximal phalanx of his thumb. Open it at its distal end; pass a probe proximally towards his wrist, and make a second incision over its proximal end (incision 12). Insert a fine catheter down the sheath and irrigate it with saline.
CAUTION ! (1) Don't incise along the radial border of his first metacarpal. Dissecting among the muscles there may impair the function of opposition, and prevent him bringing his thumb across his palm.
Fig. 8-8 SEPTIC ARTHRITIS. A, acute suppurative arthritis presenting with a sinus. B, exploring the lesion. C, mobilizing an intact extensor tendon to expose a suppurating distal interphalangeal joint. After Bailey DA, The Infected Hand', Figs. 65, 66 and 67. HK Lewis, with kind permission.
Septic arthritis of the fingers
A patient's finger joints are easily infected from open wounds, or from nearby infections. A human bite into a joint is particularly dangerous. The infected joint is acutely tender, swollen and painful. Its ligaments, cartilage, and bone are soon involved, so that he inevitably ends up with a stiff joint. A stiff DIP joint is little disability, but if he has a stiff MP or PIP joint, his finger but not his thumb are probably better amputated.
SEPTIC ARTHRITIS [s7]OF THE FINGERS Give the patient an antibiotic (8.1); but this is less important than drainage and an efficient surgical toilet.
Open the joint immediately, especially if there is a wound over it. If the edges of the wound are not obviously infected, excise their extreme margins. Examine his extensor tendon.
If his extensor tendon has not been divided, enter the dorsolateral aspect of the joint and retract it to the opposite side. Look inside the joint. Remove any debris and loose bits of cartilage or bone. Syringe it out with saline. Leave his skin wound open for delayed primary closure. If you had to divide his extensor expansion, repair it at the same time. Immobilize his joint in the position of function (7.17), in case it stiffens, not the position of safety (75.2).
If his finger (but not his thumb) is stiff, consider amputation if he is an adult[md]but not if he is a child!
Other problems with hand infections
Hand infections, particularly if they are not well treated can cause many problems. Here are some of them. For infections in leprosy hands, see Section 30.4.
OTHER PROBLEMS If, a few hours after a minor scratch, a patient's hand becomes hot and shiny, red lines spread up his arm, and he has rigors, a fast pulse, and severe headaches, he has lymphangitis progressing to streptococcal SEPTICAEMIA. This was common and usually fatal before the antibiotic era. Never incise such an infection, even with antibiotic cover. Give him an antibiotic first (2.9), and if an abscess or gangrene forms later, incise or deslough his hand.
If his hand has been infected as the result of a HUMAN OR ANIMAL BITE, do an efficient wound toilet under a tourniquet, excise all tissue of doubtful viability, and leave the wound open. Give him chloramphenicol and metronidazole (2.9). He is in great danger of a serious infection, particularly with anaerobes. If you treat him early, he will probably recover and have a useful, mobile hand. If he presents late with a finger like that in Fig. 8-9 it will remain stiff, especially if a joint or a tendon sheath are involved. When his infection is controlled, and if he will allow you, amputate his stiff useless finger.
If SWELLING AND TENDERNESS SPREAD ABOVE HIS WRIST, pus has probably tracked proximally behind his flexor tendons up his arm into the space of Parona, as the result of a neglected palmar infection[md]see Section 8.9. Drain it through incision 6 in Figs. 8-4 and 8-6.
If he has EXPOSED JOINTS OR TENDONS after a hand infection, leave them open for about a week until infection is controlled. Raise his hand in a roller towel (75-1), and start movements as soon as pain permits. When healthy granulations have appeared, refer him to an expert who will cover his exposed tendons with a flap. If you cannot refer him, close his wound by secondary closure without tension (seldom possible, 54.6), or by secondary split skin grafting unless you have experience in the use of flaps. This will be less satisfactory, because his fingers will not be so mobile.
If OSTEOMYELITIS develops, continue antibiotic treatment, immobilize his hand in the position of function, X- ray it 2 weeks later and remove sequestra through dorsal incisions as necessary. Osteomyelitis of the distal phalanx is common in untreated pulp infections (8.5), and can follow other hand infections. You may eventually have to amputate his infected finger[md]see below.
If it involves a metacarpal (uncommon), treat this as if it were any other long bone. Approach it through a dorsal incision, and reflect his extensor tendons. Approach his middle and lateral phalanges through midlateral incisions.
If it involves a distal phalanx this will usually present at his finger tip. Bite it off with a bone nibbler.
If DISCHARGE AND PAIN PERSIST, they are probably the result of: (1) Inadequate drainage and desloughing. (2) Osteomyelitis. (3) The spread of a more superficial infection to a tendon sheath, or another fascial space which you did not recognize initially. (4) Sloughing of a tendon. (5) A foreign body.
If an adult's FINGER CONTINUES TO BE PAINFUL AND DISCHARGE because of osteomyelitis or estabished septic arthritis of an MP or PIP joint, consider AMPUTATION, because the nearby joints may become stiff too. A stiff DIP joint is not a disability. When you amputate, do so at least through the joint proximal to the involved bone. Don't merely remove part of the involved bone, because the infection will spread. The thumb is an exception; spare as much bone as you can, and don't amputate if you can avoid doing so, because even a stiff stump of a thumb is better than no thumb. See Section 75.24.
CAUTION ! A child is much more likely to regain some useful movement eventually, so don't amputate unless his finger remains stiff after the infection has settled.
Fig. 8-9 DISASTER WITH A HUMAN FINGER BITE. The wound entered the patient's terminal IP joint which became infected. His finger might have been saved by an efficient wound toilet soon after the injury. Excise all tissue of doubtful viability, leave the wound open, and give him chloramphenicol and metronidazole. After Charles Bowesman Surgery and Clinical Pathology in the Tropics'. E and S Livingstone. Permission requested.
Pus in the foot
Foot infections are common, especially in communities where people don't wear shoes, but they are not as common as hand infections. Fine movements are not so important in the foot as they are in the hand, so that infection of the tendon sheaths of the foot is less of a disaster. You must however drain septic arthritis and osteitis, or persistent sinuses may follow.
Some aspects of foot infections are discussed in other chapters[md]osteomyelitis of the calcaneus and talus (7.13), and mycetoma (31.3). Leprosy patients are particularly liable to foot infections, and have their own special problems (30.6).
PUS IN THE FOOT Manage subcutaneous infections (8.2), apical toe space infections (8.3), paronychia (8.4), pulp infections (8.5) and web space infection (8.7) as in the hand. They are all fairly common
ANAESTHESIA. (1) Intravenous ketamine (A 8.1). (2) General anaesthesia (A 10.1). (3) Local anaesthesia is suitable for very localized infections.
For all but the most superficial infections use a tourniquet (3.9), unless the patient's circulation has been impaired by ischaemic disease.
DEEP INFECTION OF THE PLANTAR SURFACE OF THE FOOT is usually due to an injury, such as a thorn, which has penetrated deeply.
If you suspect a foreign body, incise the abscess, search for it and clean out the cavity thoroughly. Leave the wound open sufficiently for it to heal up from below.
If infection is spreading on to his foot and up his leg, explore and drain the lesion, and give him an antibiotic suitable for the staphylococci in your area. As in the hand, rapidly spreading infections are likely to be due to haemolytic streptococci (8.12).
INFECTIONS OF THE DORSUM OF THE FOOT present early, and can usually be drained through a small incision using local anaesthetic infiltration.
INFECTIONS OF THE TENDON SHEATHS are uncommon except in leprosy, and when there is a foreign body involving the tendon sheath. Incise over the infected part, drain, and leave the wound open. In a late case you may need to remove necrotic tendon.
SEPTIC ARTHRITIS can involve any joint.
If an IP joint is involved, open it widely through a longitudinal incision on the dorsal surface to one side of the extensor tendon. Clean it out and leave it open to drain.
If an MP joint is involved, approach it either from the dorsal surface (open it from just to one side of the extensor tendon), or from the plantar surface. Open the wound widely and let it drain. Wounds in the plantar surface heal well.
If other joints are involved, approach them from the side where the bone is nearest to the surface. Clean the joint out well and leave it open.
OSTEITIS. Give him an antibiotic (2.9) and remove necrotic bone as necessary in chronic cases.
If his phalanges are involved, drain the infection and it will probably settle. Osteitis commonly follows infection in the soft tissues, especially infections of the pulp of the distal phalanx.
If his metacarpals are involved (uncommon), he may have: (1) Osteomyelitis following an injury. Approach the bone through a dorsal incision and reflect his extensor tendons. Drain the wound and remove necrotic tissue. Loss of one or two metacarpals is of little functional importance. (2) Acute haematogenous osteomyelitis. If he is under 10 years, an antibiotic alone may be adequate. If he is over 10, his bone will also need drilling. (3) Chronic haematogenous osteomyelitis. He presents with persistent pain and sinuses. Remove necrotic bone, without waiting for the formation of an involucrum.
CAUTION ! If his foot becomes infected without obvious reason look for: (1) A foreign body. (2) Leprosy (30.5). (3) Diabetes. (4) Ischaemia (uncommon in most of the developing world: feel his dorsalis pedis and his posterior tibial pulses).
POSTOPERATIVELY, stop him bearing weight. If he has a severe infection apply a plaster gutter splint to hold his foot in neutral (69-1). This will reduce pain and ensure that his foot is in the best position if it does becomes stiff.
