Operations on the feet in leprosy

Most leprosy ulcers don't need an operation, but there are some simple operations which you should be able to do. Try to correct clawed toes, because they predispose to ulcers at the tip of a toe, on the knuckle, and under the metatarsal head. Apart from the correction of clawed toes, most other tendon transfers are work for an expert. The only other possible exception is a posterior tibialis transfer for foot drop (30.8).

Fig. 30-9 SOME OF THE SIMPLER LEPROSY OPERATIONS. A, clawed toes due to weakness of the intrinsic muscles, but without skin or joint contractures (Grade One). B, clawed toes with contractures (Grade Two). C, clawed toes with severe contractures, and dorsal subluxation of the MP joints (Grade Three). D, Lisfranc's transmetatarsal amputation, in which most of the metatarsals are removed, and the tissues of the sole turned dorsally. E, F, and G, a transmetatarsal amputation for an ulcerated foot, including the excision of the ulcers on its sole. This amputation may be possible when there is not enough tissue to make the long sole flap needed by Lisfranc's amputation, or when there are open ulcers, and thus potential sepsis. F, the longitudinal incision on the side of the big toe, nearer the dorsum than the sole. G, the stump ready for the longitudinal incisions to be closed by suture, and the end of the foot allowed to heal by granulation. H, amputating the distal phalanx. I, the completed operation. J, a heel ulcer over a bony spur. K, expose the bone from the back and side. L, remove the spur with an osteotome. M, close the wound over a rubber drain. N, the incision to transfer the long flexor tendon of a toe to the dorsum. O, the transfer completed. P, Webster's incision for excising the breast. Mostly after Paul Brand ''Insensitive Feet, A Practical Handbook on Foot Problems in Leprosy'. E, F, G, N, and O, kindly contributed by Grace Warren.

FOOT OPERATIONS [s8]FOR LEPROSY ANAESTHESIA. If a patient's hand or foot are sufficiently anaesthetic, you may be able to operate under sedation alone, especially if he is co-operative. He may even be sufficiently anaesthetic to tolerate a tourniquet if you sedate him well. If necessary use axillary (A 6.18), wrist (A 6.20), hand (A 6.21), or ankle (A 6.24) blocks, or subarachnoid (spinal) anaesthesia (A 7.4), or ketamine (A 8.1).

ULCERS If you are excising an ulcer or scar on his sole, you may be able to close the gap you have made by primary suture. This will allow healing by first intention, and will improve the quality of his plantar skin. To do this, excise the ulcer with an elliptical incision, and close the wound with deep mattress sutures (4-7) of ''0' monofilament to eliminate dead spaces. Keep the wound dry, and leave the sutures in for 3 weeks. If you can only close an ulcer under excessive tension, consider using a lateral or dorsal relieving incision, right down to the bone. Loosely pack the dorsal incision, and leave it to granulate as described below. Make sure the bridge of skin, between the ulcer and the relieving incision, is adequate to maintain the circulation.

CAUTION ! Only close clean surgical incisions by primary suture. Even some of these need drains to minimize haematoma formation. Remove the drains after 48 hours.

If you are excising a deep ulcer with a sinus track leading from it, put gentian violet into the track. If you cut away all the violet tissue, you should have removed the base of his ulcer, tracks and all.

If you are excising a heel ulcer, make a ''fish mouth' relieving incision around the back or lateral margin of the sole of his heel, as in K, Fig. 30-9. Excise and suture the plantar defect, as described above. Consider packing the ''fish mouth' wound as described below, and allowing it to heal by granulation.

If you are doing some other operation on a foot and it happens to have an open, and potentially infected, ulcer pack it as described below.

PACKING A WOUND OR ULCER. Loosely pack it with gauze strips or bandages and allow it to heal by granulation. If you use gauze squares, be sure to leave part of each piece outside the wound, so that it will not be forgotten inside. Soak the packs in hypochlorite, sugar solution, acriflavine emulsion, magnesium sulphate and glycerine, or normal saline. Remove the dressings at 5 days. Provided there is no deep infection, lightly repack the depth of the wound, but keep its mouth widely open. Repeat this every 2 or 3 days, until it has healed by granulation.

TO EXCISE A CALCANEAL SPUR [s7](OR OTHER BONY PROJECTION) A normal calcaneus has a spur which projects forwards along the line of the plantar ligaments parallel to the ground; this is harmless. If an abnormal spur, associated with an ulcer, projects vertically downwards, remove it. Also remove any irregular bone that has developed because of a fracture or an infection, and which threatens to cause ulcers by pressure from within. Don't remove these bony projections through the ulcer, because this will make the plantar scar bigger.

Instead, paint the ulcer with gentian violet. Then make an incision round the back or lateral side of the patient's heel, as in J, to M, in Fig. 30-9, so as to avoid his medial calcaneal vessels. Deepen the incision to the bone, and lift his heel pad off the bone by clean sharp dissection. Continue the incision, so as to raise a flap of heel and plantar fascia, and mobilize the ulcer. Then excise and suture it as described above. Trim his calcaneus with an osteotome to leave a flattened surface. Don't remove bone unnecessarily, or leave new sharp edges or corners to form new ulcers.

If his ulcer had already healed before the operation, insert a drain and stitch the flap back, provided there is no tension.

If his ulcer is open, excise its edges, and sew it up with deep stitches, leaving a pack in place under it, and coming out of the relieving incision as described above. The skin wound from his ulcer should heal by first intent, leaving a gap round the edge of his heel flap to heal by granulation.

If he has osteitis, excise or curette the sinus tracks and insert a pack.

If osteitis is already draining through the centre of his heel, curette and pack the lesion, without trying to excise the ulcer. Stop all weight-bearing until his ulcer is healed; give him a splint. When the infection is controlled, trim any rough bone. Alternatively, as soon as his osteitis is controlled, you may be able to excise the ulcer scar, pack the lesion laterally, and allow it to heal by granulation.

Don't let him walk on trimmed bone for 6 weeks, or until his wound is fully healed, and its scabs are off[md]unless he is in a plaster cast.

AMPUTATIONS [s7]IN LEPROSY INDICATIONS. Conserve as much bone and soft tissue as you can. The only absolute indications for a below knee amputation are: (1) malignancy, which cannot be removed in any other way. (2) Gangrene. (3) Grossly infected ulcers with inadequate bone, so that they are no longer weight-bearing.

METHOD. Ideally the stump should have sensation. If not, he will need a good prosthetist and careful training. Use one of the methods below, and only do a below-knee amputation as a last resort: it may however be the operation of choice if the tibial area is sensitive. The method of Anderssen and Perssen was specially devised for leprosy. Use a tourniquet (3.9), and see Sections 56.1 and 56.8. The longer his tibial stump, the easier it will be for him to learn to walk with a prosthesis. If he is a healthy young adult, you may be able to take skin flaps almost to his malleoli. If his circulation is poor make a shorter stump. If you amputate through his foot, try to leave as large a weight- bearing surface as you can.

If his foot has become shortened, his toes may remain projecting, and make it difficult to fit a shoe, or they may be subject to excessive pressure. If so amputate them.

If the soft tissue under his metatarsal heads has become so scarred that it constantly reulcerates, remove the distal ends of his metatarsals through dorsal incisions. Keep his toes in line with his sole by bandaging them to a flat board while they heal.

If his foot is chronically scarred and ulcerated, and he has lost part of all his toes, but has good sole tissue proximally, do a transmetatarsal amputation, as in D, Fig. 30-9. Make a dorsal incision and divide the bones along a line proximal to the scar. Without removing tissue from the sole, turn a long sole flap, including the scar up, and around the ends of the bones, bringing the suture line dorsally. The most proximal line for this amputation is through his tarsometatarsal joints (Lisfranc amputation). At this level, you will have to saw through the neck of his 2nd metatarsal, the base of which is more proximal.

CAUTION ! Foot operations leaving shorter stumps are prone to develop complications. So avoid them, unless arthrodeses or stabilization of the ankle are possible.

If he has severe ulceration, poor toes, and not enough sole tissue for a long sole flap, make an incision right round the dorsal and plantar surfaces of his forefoot, at the base of his toes. If possible try to keep some of the skin of his toes on the foot flap (E, in Fig. 30-9). The dorsal skin flap does not need to be as wide as the plantar one, so when you incise his foot laterally to make them, do so as far dorsally as you can (F).

Starting at the base of his toes, strip the soft tissues off the bones, and remove all rough infected pieces of bone, far enough back for the most distal part of the remaining healthy bone to lie over a fairly healthy area of skin. Trim all his metatarsals to a suitable length, so that one does not stick out in front of the others. Smooth the rough bone ends. The dorsal and plantar flaps should meet in front of his foot. Excise any ulcers on the sole of his foot, and suture the gaps you have made with monofilament longitudinally as described above.

CAUTION ! Don't suture the end of his foot. Instead, pack it and allow it to heal by granulation. This will increase the tissue over the ends of his metatarsals, and allow you to operate while he is still infected and ulcerated.

Try to stop him walking for at least 6 weeks. If absolutely necessary, put him into a walking cast, with his ankle in good dorsiflexion, and with sufficient plantar protection to stop him bumping the healing area. Leave the end of his granulating foot protruding for dressings.

If his heel pad has some sensation and a good prosthetist is available, consider doing a Symes amputation (56.9). A Symes stump is too short and too small to be used for weight-bearing unless he has a good elephant boot.

TENDON TRANSFERS [s7]FOR CLAW TOES (Girdlestone type) INDICATIONS. Mobile clawed toes in Grades One or Two (30.6). This operation allows his toes to take more part in weight-bearing, and so protects his metatarsal heads.

ANAESTHESIA. (1) Toe or ankle blocks (A 6.21). (2) Ketamine (A 8.1). (3) Subarachnoid anaesthesia (A 7.4).

METHOD. Under a tourniquet, incise along the midline of the medial side of the middle and proximal phalanges of the toe whose tendon you want to transfer. Proximally, curve the incision dorsally to reach the dorsum of his foot at the distal end of the web. Find his long flexor at his DIP joint. Hold it in forceps, and cut it distally. Cut his flexor sheath back to the middle of his proximal phalanx. Lift the skin and soft tissue off the dorsum of his proximal phalanx and interphalangeal joint, and transfer his long flexor tendon so that it runs diagonally across his proximal phalanx, and reaches the long extensor tendon of that toe. Suture it to his long extensor tendon, proximal to his PIP joint. If his flexor digitorum longus is transferred at this level it will remain a flexor of his MP joint, but will now extend his PIP and DIP joints. Close his skin with monofilament. Splint his foot on a flat board for 3 weeks, and don't allow him to walk. There is no need for physiotherapy.

REMOVING TOE TIPS [s7]FOR LEPROSY INDICATIONS. (1) Fixed flexion of his toes, so that he is walking on the tips of his toes, or on his nails. (2) Repeated ulcers on the tips of his toes.

METHOD. Cut round his nail and across the skin over his DIP joint. Dissect out his distal phalanx, leaving all pulp possible (H, Fig. 30-9). Close the incision with a few mattress sutures (I), and don't worry about dog ears: they will soon atrophy.

EXCISING METATARSAL HEADS [s7]FOR STIFF, CLAWED LEPROSY TOES INDICATIONS. More than one stiff, clawed toe of Grades Two or Three, or ulcers under his metatarsal heads. Sepsis is not a contraindication, because you leave the dorsal wound open and pack it.

Aim to reduce the scarred area, by shortening the metatarsals of one or all of his toes, so bringing his toes down to take some weight. Keep all incisions dorsal where you can, and aim for a mobile pseudarthrosis, not an ankylosis.

METHOD. Over his stiff toe make a dorsal incision which is long enough for you to see his MP joint, and 2 cm of his metatarsal. Elevate his periosteum, and remove his metatarsal head with bone nibblers or cutters. Base the site of bone section on the thickness and quality of his plantar skin. Save as much plantar surface as you can, provided it is of reasonable quality. Smooth the remaining shaft with a small bone file or nibbler. You should now be able to straighten his toe; if it is still dorsiflexed, remove a little more metatarsal. If there is much scarring under his metatarsal heads, consider removing all of them. Don't leave one metatarsal obviously longer than the others. Excise any ulcers on the sole, as above, and close the gaps with monofilament.

Try to avoid damaging his proximal phalanges. If you can find any flexor digitorum longus tendons, release them distally and anchor them over his proximal phalanges, as in the claw toe method above.

For each toe, cut the branches of extensor digitorum longus and brevis to prevent extension. Tack the proximal cut end of the tendon to the remains of his metatarsal to prevent it reattaching itself to the distal end.

Leave the dorsal incision open, pack the wound, and allow it to heal by granulation. Splint his toes straight on a board for three weeks or longer, while his foot heals. When excessive discharge has stopped, consider applying a cast with a window and letting him walk. Ideally, he should not walk, unless he is in a walking cast, for a minimum of 6 weeks, or until his foot is fully healed and the scabs are off.

If you are operating on the head of his 1st or 5th metatarsal, do it in the same way. Make an incision on the medial or lateral side of his foot, but make sure there is enough width in the skin bridge to prevent it necrosing. The width of the flap of skin between the excised ulcer and the relieving incision must be at least half its length (as in making flaps and pedicles).

If all his toes are affected, you can remove all his metatarsal heads through 3 or 4 longitudinal incisions.

If he has marked osteoporosis, apply a walking cast for 2 to 5 months to allow his damaged bones to recalcify, as they will do when infection is controlled. His bone will still look osteoporotic on X-ray; but, provided he returns to walking gradually, it should recalcify without breaking.