Orthopaedics
From Primary Surgery
Contents |
27.1 The scope of primary othopaedics
Most of your orthopaedic problems will be the fractures that are described in detail from Chapter 69 onwards. Many of the non- traumatic conditions you will see are also described in other chapters: they include osteomyelitis (Chapter 7), septic arthritis (7.16), and tuberculous bone and joint disease (Chapter 29). The orthopaedics which remains to be considered here consists of the important subject of contractures in general (27.2), polio (27.3 to 27.7), talipes (27.15), and a few minor orthopaedic probems that you can treat without difficulty, such as epicondylitis ('tennis elbow', 27.9), stenosing tenosynovitis (27.10), ingrowing toenail (27.16), and a few others (27.17). Try to obtain the following superb manual, which describes the management of all kinds of disability in the community: David Werner, 'Disabled Village Children, A GUide for Community Health Palo Alto California CA 94302 USA
27.2 The general method for contractures
A contracture is a deformity which prevents the movement of a joint through its normal range. Structurally, contractures are the result of shortening of the soft tissues of a limb, and!or tightening of the ligaments of a joint. This can happen as the result of: (1) Disuse (see below). (2) Soft tissue or bony injuries, especially burns (58.24 to 58.26) and fractures. (3) Muscle imbalance, due to weakness of the nerves supplying a group of muscles. This can be temporary, when you expect the nerve to recover, or permanent, when you expect it not to. (4) Poliomyelitis, and other lower motor neurone lesions, which weaken one muscle group more than another. (5) The spastic paralysis of an upper motor neurone lesion, such as that following a cerebrovascular encephalitis, or a head injury. (6) Sepsis in bones (osteomyelitis,7.2), joints (septic arthritis,7.16), or lymph nodes with pariadenitis 9iliac abscess, 5.12). That 'prevention is better than cure' is never more true than with contractures. If a joint is to remain useful, it must move regularly through its full range. Anything which prevents it from doing this eventually causes a contracture. The soft tissues surrounding a disused joint become shorter, and less elastic, and its muscles waste and will not extend normally. Ultimately, its bones change their shape, and become deformed; it lacks a full range of move- can easily break a bone when you manipulate it, so follow the ment, or becomes fixed near one end of its range, usually flexion. The two important principles in prevention are: (1) Most importantly, to keep all joints moving whenever you possibly can. The need to do this is well shown by the the patient with the severe buttock injury in Figure 54-10. When she was admitted, both her elbows were normal, but as she lay on her front for several weeks, she kept them flexed, and never moved them. The result was that when she was discharged, she had severe contractures in both her elbows, which had been perfectly normal on admisssion. The burnt child in Fig. 58-1 developed contractures in his unburnt joints because he did not move them. Contractures like this can happen quite unnoticed, and when you do notice them,it may be too late. (2) When movements are temporarily difficult,or inadequate for any reason, prevent deformity by splinting or skin traction (70.10), as with the burnt child in Fig. 58-17. Treatment starts with a careful assessment, so begin by deciding: (1) Which tissues are causing the patient's contracture? If his joint is merely stiff, releasing it should not be too difficult. If only his skin, subcutaneous tissues, and muscles are involved, you should also be able to release them. But contractures of his tendons, or nerves (as in his popliteal fossa), are more difficult. Involvement of a joint can be due to: (a) Mild or dense adhesions.(b) Shortening of its capsule or ligaments. (c) Destructive changes,as the result of past infection. (d) A fibrous ankylosis. (e) A bony ankylosis. If his bones are not deformed, you should be able to release his contracted soft tissues. If they are deformed, you will have to refer him for an osteotomy. (2) What range ofmovement is there in the joint? Record the movement he still has. (3) How much power is there in his muscles? This is important if he has a lower motor neurone lesion, such as that following polio, or an upper motor neurone lesion as the result of paraplegia. Muscle power is graded from 0 to 5. The important grade is 3,because this is the grade at which a muscle is just able do its work against gravity. It varies with the muscle; the quadriceps,for example, has to lift a heavy leg against gravity, whereas the extensor of the little finger has only a finger to lift. Any muscle which can lift its part of a limb against gravity, must have a power of at least 3. Charting is difficult to do accurately, especially in young children. In an older patient trick movements can easily deceive you. Try non-operative methods first. You have several choices: (1) You can use active and passive movements. These might seem the simplest, but they need a determined physiotherapist, or someone, such as a nurse, with some physiotherapy training. (2) You can apply skin or skeletal traction (70.10, 70.11). (3) You can manipulate a joint. (4) You can apply serial corrective casts. Manipulation and casts can often be usefully combined. For ex- ample, you can manipulate a joint, and then apply a cast almost at the limit of its range of movement. Later, you can manipulate his joint again, and replace the cast with another one, in which his joint is nearer to the limit of its normal range of movement. If manipulation is to be thorough, you will have to anaesthetize him. The danger is that, during manipulation, a joint may bleed, waste and will not extend normally. Ultimately, its bones change and the blood in it may organize and cause more adhesions. You can easily break a bone when you manipulate it, so follow the instructions we give, which are designed to prevent this happening. You can also wedge a cast, as in Figs. 70-8 and 70-9. This is economical in plaster, but it has the disadvantage that you cannot combine it with manipulation. (5) You can release soft tissues surgically. Polio contractures are easier to release than the contractures which follow burns, because there is less scar tissue, and no skin loss.
PREVENTING CONTRACTURES IS EASIER THAN TREATING THEM
GENERAL METHOD FOR CONTRACTURES
PREVENTION. Most contractures can be prevented by: (1) Put- ting a patient's joints through their full range of active and passive movement, several times a day, as with paraplegia (64.13). This is such a simple measure, yet it is so often forgot- ten. You probably won't have physiotherapists, but this is something that all nurses can do so show them how. (2) Appropriate splinting, as for burns (58.24), tuberculosis of the knee (29.3), or a radial nerve palsy, as in Fig. 69-2. (3) Skin traction for burns, as in Fig. 58-17. (4) Early movements in bone and joint injuries, as with Perkins traction for a fractured femur (78.4), or fractures of the femoral condyles (79.15). (5) The early drainage of pus, as with septic arthritis of the hip, which readily causes a flexion contracture (7.18). (6) The early grafting of wounds and burns over joints (58.32). (7) Early manipulation and immobilization, as for neonatal talipes equinovarus (27.15) Often, you will need to do several of these preventive measures at the same time. For example, you may need to combine splinting and active and passive movements.
ASSESSING A PATIENT WITH A CONTRACTURE Where relevant, assess him lying, sitting, standing, and walking. Remember that abduction is movement away from the midline, and adduction is movement towards it. 'Varus' is a deformity towards the midline from the line of a long bone, and 'valgus' is a deformity away from it. In an equinus deformity of the ankle the foot points downwards, like that of a horse (equus, a horse), in a calcaneus deformity his foot points upwards so that his calcaneus is downwards.
RANGE OF MOVEMENT. In the anatomical position all joints are at 0°, so record the movement he has from this position (69-1), and state whether they are active or passive. For example, the range of movement for a normal hip could be: flexion 0°/120°, that is from 0° to 120°. Its other movements might be extension 0º/10º abduction 0°/40°, adduction 0°/30°,external rotation 0°/60°, internal rotation 0°/30°. 'Normal' peo- ple vary somewhat. A patient with a flexion contracture might have: flexion 30°/110°, extension - 30°/- 30° (this means that there is no extentionin his hip, movement starts at -30° of extension and ends there), abduction 0°/20°, adduction 0º/20º internal rota-tion 0°/10°, external rotation 0º/40º. This means that his hip is flexed, but will not extend at all; it will flex a bit more, but not as much as normal. In other directions its movements are slightly limited.
MUSCLE POWER and movements are usually assessed by a physiotherapist, but if you don't have one, you will have to assess them yourself. Grade O-no power, not even a flicker. Grade 1-a flicker of movement, but no more. Grade 2-movement with gravity eliminated. Grade 3-movement is just possible against gravity. Grade 4-movement is possible against gravity and some resistance. Grade 5-full normal power.
PARTICULAR JOINTS. A contracture of one joint can affect movement in another, so assess him like this. Hip. If you are assessing a flexion contracture of his hip, flex his other hip as far as it will go. This will correct any lumbar lordosis, which may disguise as much as 60° of fixed hip flexion. Extend and adduct his hip, because a tight abduction contracture may be responsible for most of his deformity. Knee. If you are assessing a flexion deformity of his knee, do so with his hip in both the neutral and the flexed positions. Assess a varus or valgus deformity from the line of the shaft of his femur. Assess backward, or lateral subluxation of his tibia on his femur as mild, moderate, or severe. Assess exter- nal rotation of his tibia on his femur with his knee extended as much as possible. Ankle. If you are assessing an equinus deformity of his ankle, do so with his knee flexed and extended, because this will help in deciding management. If the deformity is in his ankle joint, it will be the same whether his knee is flexed or extended. But if the deformity is in his gastrocnemius muscle, the range of movement in his ankle will vary with the position of his knee. This is because the gastrocnemius muscle spans both the knee and the ankle. So, if this is short an equinus deformity of his ankle will be less if his knee is flexed, than if it is extended, because his gastrocnemius is not being stretched by an extended knee.
X-RAYS. If necessary, X-ray the bones and joints involved in his contracture. Look for: deformity of the joint surfaces, evidence of active disease, and the degree of osteoporosis.
TREATMENT FOR CONTRACTURES The need for treatment usually means that prevention has fail- ed. See elsewhere for burns (58.25, 58.26), for polio contractures (27.3 to 27.7), and for paraplegia (64.13). Here are some general methods which you can apply to most contractures. The first two are the safest.
ACTIVE AND PASSIVE MOVEMENTS FOR CONTRACTURES These may gradually stretch a patient's shortened soft tissues and correct his deformity. If possible, encourage him to do them himself (active movements). Or, they can be done by a physiotherapist, or nurse (passive movements). Most useful are'assisted active movements': (1) Support his limb while he gently moves it himself. This eliminates gravity and gives him a greater feeling of security.(2) At the extremes of movement use a little passive movement, as he moves his limb himself assisted by you. Chart the range of its movement at least every week.
TRACTION FOR CONTRACTURE If satisfactory correction is not possible by exercises alone, consider skin traction (70.10), or skeletal traction (70.11).
MANIPULATION FOR CONTRACTURES This is often combined with casting.
INDICATIONS. (1) Joints in which active and passive movements or traction have failed, or are not possible because the deformity is too great. (2) Hip contractures of less than 45º.(3) Knee contractures of less than 30°. (4) Ankle contractures of less than 20°.
ANAESTHESIA, If you decide to anaesthetize him, ketamine will be adequate.
METHOD. Press firmly for at least five minutes in a direction opposite to that of the contracture. If necessary, repeat the manipulations fortnightly. CAUTION! Before you begin, remember that a bone which has not been moving is soft and breaks easi Iy. To prevent this, reduce the leverage that you can exert, by holding a patient's bones close to his contracted joint, as in Fig. 27-2. HIP Flex his opposite hip to eliminate a lumbar lordosis. Press the upper third of his thigh backwards, to bring his leg down on the table in slight abduction. This will also stretch his ad- ductors, which will probably be tight.Laying the patient prone is a very useful nursing procedure for preventing and treating flexion contractures of the hip. If he will tolerate it, lay him face down with a pillow under his lower thigh. He is more likely to accept this uncomfortable position if his head faces towards the middle of the ward, rather than the wall. KNEE, Hold his knee close to the joint. If you don't, you may break his tibia or his femur, displace his epiphyses, or sublux his tibia on his femur. CAUTION! Don't try to release contractures of his knee too forcibly, or you may injure his popliteal nerve, or damage the joint. ANKLE, If he has an equinus deformity, support his ankle, and firmly dorsiflex his foot. If he has a varus deformity, or an adduction deformity of his forefoot, be especially firm and gentle. Don't push up his forefoot only; this may merely extend his mid tarsal and tarsometatarsal joints, without extending his ankle.
CASTING FOR CONTRACTURES Apply a well-padded plaster cast, close to but not at the extreme range of movement of the joint. If you do, pressure on its cartilage may cause necrosis and osteoarthritis later. So let it relax a little, before you apply the cast. A few weeks later, if necessary, manipulate his joint again, and replace the cast with another one, in which his joint is nearer to the limit of its normal range of movement. CAUTION! (1) Never put a joint, especially a knee, into a cast under tension. (2) Don't wedge a cast to correct a knee contracture. Both these mistakes may cause an early painful osteoarthritis, in what was previously a painless mobile joint.These are both very important rules. Fortunately, osteoarthritis and painful joints are rare in polio; it is tragic to create them unnecessarily.
OPERATIVE METHODS FOR CONTRACTURES You can release his soft tissues if he has a burns contracture(58.25 and 26). If he has polio, you can release the tendons of his ankle (27.7), his knee, or his hip (27.6). If his contracture is severe and long-standing, you may be able to refer him for a release combined with a myocutaneous flap, or by an osteotomy.
27.3 Preventing contractures in the acute and subacute stages of poliomyelitis
If a child has paralytic polio, teach his parents how to prevent contractures as soon as his pain allows-they can start only a few days after the acute illness. Preferably four times a day, his joints must be stretched in the direction opposite to that in which a contracture might form-for example, stretch an equinus ankle contracture dorsally. Teach them the methods in Fig. 27-2.Fit him with a caliper, as soon as his tender muscles will allow. In the acute stage, leave this on for most of the day and the night.Or, use a plaster gutter splint.Start to assess the power of his muscles (27-1) as soon as the tenderness allows, usually about three weeks after the start of paralysis. If you assess the degree of recovery each time you see him, you will be able to judge how far he will recover finally. Three months from the onset of paralysis, you will know whether he needs calipers or not. CONTRACTURES CAN FORM IN A FEW DAYS
27.4 Managing Chronic Polio
The children of the developing world pay a high price for acquiring their natural immunity. A survey from Ghana showed seven in every thousand to be lame, and although nearly 90% of these children could walk without mechanical aid, many of them had scoliosis and needed calipers. Poliomyelitis destroys the anterior horn cells of a patient's spinal cord. This causes a flaccid lower motor paralysis, without impairing sensation. The flexor and extensor muscles of a normal limb are arranged so that they oppose one another's action. Polio can weaken both groups mildly or severely, equally or unequally. When, as is usual, the muscle groups are involved unequally, it is commonly his extensors which are most affected. When this happens, his stronger flexors pull his limb into a flexion contracture. If all the muscles of his limb are weak, he has a flail limb. If he is a child, growth will cause further deformity. All this can happen in varying degrees to his hips, his knees, or his ankles, on one or both sides, to cause many patterns of paralysis. His arms are less commonly affected, and are usually less of a disability, so we say nothing about them here, nor do we discuss the effects of polio on the spine.
These are your opportunities: (1) Do all that you can to promote the immunization campaigns that should now be taking place in your district in response to WHO's expanded programme of immunization (EPI). (2) Try to prevent contractures develop- ing immediately after the acute phase of the illness. (3) If they do develop, use serial plasterings, tractions or tenotomies to release some of the milder ones. More complex operations, such as osteotomies, arthrodeses, and tendon transfers, are tasks for an expert, so are all operations on the arms and spine, on the rare occasions when these are necessary. (4) Provide patients with the necessary calipers, crutches, and plaster splints. (5) Follow them up for many years, if necessary, and help them to find places in schools, and to find jobs. As always in medicine, but particularly in polio, consider a patient's total needs. Never treat a single joint without considering the other joints in his limb, his other limb, and the adaptations that he has already made to his disability.
Your results should be good if: (1) you operate carefully on the right indications, (2) you give him simple calipers, and (3) you are able to provide the necessary physiotherapy and follow-up. These last two are likely to be your main constraints. The methods we describe are adapted from those of Huckstep. In some countries they are mostly done by orthopaedic assistants.
Huckstep RL. 'Poliomyelitis: A Guide for Developing Countries, including appliances and rehabilitation' ELBS version. Churchill Livingstone, 1975.
Nicholas 0,et al.Is poliomyelitis a serious problem in the developing countries?-The Danfa Experience. British Medical Journal 1977;1:1009-12.
A GENERAL METHOD FOR CHRONIC POLIO
A patient with chronic polio can have any of the following pat- terns of paralysis: THE HIP IN CHRONIC POLIO
A MILDLY WEAK HIP (common) needs no treatment, especially if he also has a mild equinus deformity of his ankle, which helps to compensate for the shortening caused by his hip.
A FLEXION AND ABDUCTION CONTRACTURE OF THE HIP (common) due to weakness of its extensors and adductors. If an adult or child has an isolated flexion contracture of his hip of < 30º he is probably walking adequately, and needs no treatment, provided he has no other serious contractures. The stability of his hip may even be improved, and shortening compensated for, by a small adduction and flexion contracture. If an adult or child has an isolated flexion contracture of >30º, consider releasing it.
A FLAIL HIP (fairly common) due to paralysis of all its muscles. Give him a pair of crutches.
DISLOCATION OR SUBLUXATION OF THE HIP (rare) mayoc- cur in a flail hip. Reduce his dislocation, and put him into an abduction spica (77.3). Give him crutches. Occasionally, he may need an osteotomy, an arthrodesis, or a psoas transfer. Reduc- ing a dislocated hip can be difficult. Some surgeons would leave a flail hip because it so easily redislocates. If his dislocation is recurrent, it may be best left untreated. Unfortunately, most dislocations are recurrent, because there are no functioning muscles left around the hip to hold it in place.
THE KNEE IN CHRONIC POLIO Not all weak knees need a complete caliper. Some patients may be able to manage with a knee splint.
A FLEXION CONTRACTURE OF THE KNEE (common) due to weakness of its extensors. If a patient has an isolated flexion contracture of his knee of < 30º apply serial casts for a child (27.2), and skin traction for an adult. CAUTION !Never put a cast on a knee (or any other joint) while it is held under tension, or osteoarthritis will follow (27.2). If a patient has an isolated flexion deformity of his knee of >30 but <90º consider releasing it surgically (27.6). The operation described in Fig. 27-8 is a very limited open tenotomy suitable for a patient: (1) who needs a bit more extension, so that he can be put into skin traction, and (2) whose biceps femoris tendon is tight, but not his semitendinosus and semimembranosus tendons, which are attached medially. Feel his tendons when his knee is extended to its limit. If all his tendons are tight and need surgical relase, refer him. If an adult has a flexion deformity of >90º, correction is going to be difficult, and he may subsequently have a stiff painful knee. If he has one contracted knee, either leave him alone, or consider referring him for an osteotomy or an arthrodesis. Don't ever consider straightening two contracted knees in an adult.
A VALGUS DEFORMITY OF THE KNEE (common) is usually associated with a flexion contracture, for which he needs a surgical release and a caliper. If necessary, bend his caliper, or fit it with a valgus knee strap, to prevent it rubbing against his knee. If a small child has a severe valgus deformity of his knee, refer him for an osteotomy, or stapling of his medial epiphysis by an expert.
LATERAL ROTATION OF THE TIBIA ON THE FEMUR, or LATERAL SUBLUXATION OF THE KNEE (common). He usually also has a flexion contracture of his knee. You may be able to correct rotation and subluxation at the same time that you correct his flexion contracture. More often, the deformity is structural by the time you see him, and cannot be corrected by simple tenotomies. If rotation and subluxation are his only deformities, they are usually asymptomatic, and do not require specific treatment.
A HYPEREXTENSION DEFORMITY OF THE KNEE (genu recurvatum, fairly common) is due to early weight-bearing on a weak knee. If a child's knee has less than 10 degree of hyperextension, leave it untreated. If a child has >10 degree of hyperextension, fit him with an above knee caliper with a posterior strap. If an adult has a hyperextended knee, leave him untreated, provided it is not getting worse, or causing complications. Otherwise, he may need an osteotomy.
COMBINED HIP AND KNEE CONTRACTURES. If these are less than 30° and he is walking, leave them. If they are> 30°,consider releasing them, provided there are no contraindications. FLAIL KNEE. He may be able to walk adequately without a caliper, if he has good hip extensors, and if his foot is in a good position.
THE ANKLE IN CHRONIC POLIO AN EQUINUS DEFORMITY OF THE ANKLE (very common) due to paralysis of its extensors. If he is a child and flexion of his knee allows you to bring his ankle up into neutral, correct his deformity by serial castin(27.2). If he has a greater degree of deformity than this, do a tenotomy.If he Is an adult, the decision as to whether an operation would improve him is difficult, and depends on: (1) the degree of equinus of his ankle, (2) the power in his knee and hip, (3) the condition of his other leg, (4) whether he can or cannot use crutches, and (5) whether he will need calipers after surgery and can get them.
A CALCANEUS DEFORMITY OF THE ANKLE (rare) due to weakness of his calf muscles. If his calcaneus deformity is mild, a lace-up boot may be all he needs. If his calcaneus deformity is more severe, fit him with a below-knee caliper with a front stop.
A VALGUS DEFORMITY OF THE ANKLE (common) is usually associated with some degree of equinus. If his valgus deformity is mild, correcting his equinus defor- mity and fitting him with a caliper will probably be enough. If his valgus deformity is severe, consider referring him for transfer of his peroneal tendons, and perhaps a triple ar- throdesis.
A VARUS DEFORMITY OF THE ANKLE (rare) is due to weakness of the evertors of his foot. His foot is inverted and his forefoot may be adducted. If his varus deformity is mild, fit him with a below-knee caliper. If his deformity is severe, you wi 11 probably have to refer him for soft tissue correction, or a subtaloid triple arthrodesis.
AN ADDUCTION DEFORMITY OF THE FOREFOOT. Try several manipulations as in L, Fig. 27-2. You will probably have to refer him for surgical correction.
A CAVUS FOOT. You may need to refer him for tenotomy, tendon transfer, or arthrodesis of his toes. Surgery is complex,so that scarce orthopaedic skills are probably be best reserved for other patients.
COMBINED DEFORMITIES IN CHRONIC POLIO A common pattern is a flexion deformity of his hip and knee, and an equinus deformity of his ankle. Provided there are no contraindications (27.6, 27.7), treat these as if they were isolated deformities. If they are all severe enough to need release, considerreleasing his hip and knee first, and then his ankle. Refer him if you can.
SHORTENING IN CHRONIC POLIO Apparent shortening is due to tilting of his pelvis, as the result of an adduction or abduction deformity of his hip. True shortening is a real shortening of his leg, and in polio is due to the failure of a paralysed leg to grow. If necessary, correct an abduction contracture of the hip, a flexion contracture of the knee, or an equinus contracture of the ankle. If his shortening makes walking difficult (usually> 4 cm), raise his short leg with a clog or with boots. If necessary, fit calipers.
DIFFICULTIES WITH CHRONIC POLIO If he BREAKS HIS FEMUR OR HIS TIBIA, fit him with a cast, use the opportunity to correct any deformity, and keep him walking. His knee and ankle are unlikely to be functional, so stiffness will not be a problem. Perkins traction (78.4) may be useful for a short period initially.
27.5 Appliances for Polio
When you have released a patient's contracture, the muscles of his leg will still be weak, so you will probably have to provide him with a brace, or a crutch, or both. A weak hip needs crut- ches, a weak knee needs a long caliper, and a weak ankle needs a short one. If you cannot provide him with calipers, don't try to release his contractures. There are four types of orthopaedic appliances of increasing sophistication: (1) Appliances of the traditional type, such as the pads, kneelers, sticks, peg legs and crutches, that are used in traditional societies everywhere. Unfortunately, there are no traditional calipers. 2) Appliances of the Huckstep type, shown in Fig. 27-6. These can be made in a hospital workshop using locally available iron, galvanized wire, wood, and leather, and can be repaired by a bicycle mechanic, a cobbler, or a blacksmith. If they are properly made with hardwood, a child will usually outgrow them, and need a larger size before they wear out. If they are made of soft wood they wear out quickly. (3) Appliances of an intermediate type are more durable than Huckstep's. They are cheaper than appliances of type (4), and are less dependent on imported materials. An example is a modified Bata shoe with a metal tube to support the end of the iron bar. If these shoes have an open toe, they will fit feet of various sizes, but are less durable in wet weather. The leprosy shoes in Section 30.5 are of this kind. (4) The expensive high-technology appliances that are standard in the industrial world. These need imported materials, particularly duralumin and special plastics, and can only be made and repaired by a skilled prosthetist. Unfortunately, many prosthetists consider it a matter professional pride to make only the most sophisticated appliances of this type, which patients cannot afford. Resist their efforts, and encourage them to make appropriate appliances in sufficient quantity. If you cannot get ready-made appliances from an orthopaedic service, ask your hospital workshop to make those of Types (2) or (3). All large or medium-sized hospitals, doing much surgery, need a workshop making a wide range of appliances of level (3). You will need above- and below-knee calipers, fitted when necessary with backstops or frontstops. These differ only in length, in the diameter of the ring, and in the presence of a knee piece in an above-knee caliper. Calipers of Types (2) and (3) have irons each side of the leg. Although the single outside or inside irons of the calipers of Type (4) look more elegant, they are weaker, they are more difficult to make and adjust, and they are usually less effective than double ones. Use calipers to prevent deformities in a weak limb, and to straighten and support a child's leg after you have corrected his contracture. There are few indications for fitting calipers on an uncorrected contracture. Fit them as soon as he starts to walk, and replace them with a larger size as he grows. Encourage all children,who have muscle weaknesses which might lead to deformities, to wear calipers until they have stopped growing, even if they can walk without them. The indications for fitting an adult with a crutch, or a caliper, are the same as in a child, except that an adult has usually had polio many years ago in childhood, so that his deformities are now stable, in that he is unlikely to get new ones.
ORTHOPAEDIC APPLIANCES FOR POLIO
ABOVE KNEE CALIPER
If you are uncertain if a knee or ankle caliper is going to be useful or not, consider applying a suitable plaster cast of the same function for 4 to 6 weeks. If it is helpful, make a caliper. In this way you will avoid making calipers that do not help. INDICATIONS. Fit a child with an above-knee caliper if: (1) His knee is so weak that he is unable to lift his leg against gravity (the power in his quadriceps is <3). If he can lift it against gravity, a caliper will not help him. (2) He is likely to develop a contracture as the result of muscle imbalance. (3) He has a mild knee contracture of less than 30 degree that a caliper could correct, if he wore one during the day or at night. (4) He is developing a hyperextended knee, as the resu It of trying to lock and stand on it. (5) He has weak quadriceps, and at the same time too much equinus to let him swing his leg, and lock his knee. CONTRAINDICATIONS. Don't fit him with an above- or a below- knee caliper, or crutches, if: (1) He is able to walk reasonably well with a flail ankle-walking may be easier without them. (2) He is able to walk reasonably well with a weak knee. He may have learnt to use his hamstrings to extend his thigh, and lock his knee. (3) He needs crutches (because of weak hips), but does not have enough power in his triceps, shOUlders, or trunk to use them. (4) You have not corrected his deformity (unless it is a very mild one, and the caliper is designed to correct it). FITTING. Choose a caliper which reaches about 2 cm below his ischial tuberosity when he is standing, make the straps fair- ly tight, and make sure that the knee piece gives his knee ade- quate support anteriorly. Make the posterior strap slightly loose, unless his knee is abnormally hyperextended. If he has a mild flexion deformity of his knee, fit him with an ordinary caliper with a loose posterior strap, and a tight knee piece, which may need to be padded. If his knee is hyperextended (genu recurvatum), you can correct this easily, so apply only slight tension to the posterior strap. If he has a valgus knee, bend the caliper to avoid his bony points, and fit him with an inner knee pad tied to the outer side of his calipers, to prevent his knee from rubbing against the inside iron, especially when he is bearing weight. Fit it so that it presses on the medial side of his knee, and corrects the deformity as he walks.CAUTION ! A long caliper keeps a knee straight, and lets him walk. But, because his knee does not bend, it may become fixed in extension, and be a nuisance when he sits. So make quite sure that when he takes his caliper off, he puts his knee through a full range of passive flexion. This should not bea problem, if he takes off his caliper each night.
BELOW-KNEE CALIPER FOR CHRONIC POLIO
INDICATIONS. Provided there are no complications (see above), fit him with a below-knee callper if his foot is flail or drooping, or is tending to go into varus or valgus, provided the power in his quadriceps is > 3. If it is <3, he needs an above-knee caliper. FITTING. Choose a caliper that will allow his knee to flex ful- ly, with a socket which will fit firmly, and not allow too much movement. Always fit a supporting ankle strap. If his calf muscles are so weak that his foot dorsiflexes ex- cessively, fit him with a front stop. If he has little power in his dorsiflexors, so that his foot goes into equinus, fit a backstop. If his ankle is inverted or everted, fit the appropriate inner or outer T-strap.FOLLOW UP Try to see him at least every 6 months. Replace his caliper with a larger one as he grows. A long caliper is no use if it ends just above his knee! Make sure that his family understands that he will need a caliper for life. Do all you can to help him with his education.
OTHER APPLIANCES FOR CHRONIC POLIO
CRUTCHES. You will need a variety of sizes. If possible, make them to measure. If necessary, you can use any straight stick with a handle and a bar for the axilla. He will find a crutch useful if polio has weakened his hips. Let him try one and see how he manages with it. His grip must be strong enough to hold it, his triceps must be strong enough to propel him forwards, and his spine must be strong enough to allow him to sit without help. A crutch is likely to help him if: (1) Both his legs are in calipers. (2) One leg is in calipers, and his opposite leg or his spine are weak. (3) One leg is in a caliper and is very weak, and his hip on the same side is weak. Fit crutches as in Section 77.1. The length and the position of the hand grip must be right. Many patients who are given crutches could manage equally well with a stick. It you try him with a stick, teach him to hold it on the opposite side to his weak or weakest leg. If his hands are too weak to hold ordinary crutches, he may be able to use forearm crutches. CAUTION! Make sure that he does not lean on his crutches, while they are in his axilla. He may paralyse his radial nerve, or even all the nerves to his forearm and hand, and they may take 6 months to recover. A TOE SPRING may be of great help if he has foot drop. Fix a suitable spring, or a piece of bicycle tubing to the toe of his shoe and to a strap below his knee (30-5). Alternatively, fit a back stop, which is easier to fit. AN ANKLE SPLINT will be useful if he is in dangerof foot drop while he is in bed. Make a suitable splint from plaster, or padded boards, to keep his foot at 90 degrees to his leg. A RAISED SHOE will help him if one leg is >4 cm shorter than the other. Any cobbler will raise it for him. If he has <4 cm of shortening, do nothing (78.1).
27.6 Contractures of the hip and knee
Before you decide on any operative treatment, assess the func- tion of the patient's limbs in detail, and what he needs to do with them. He may have already achieved remarkable mobility, and although a straight leg may look better, it may not work better, especially if it needs calipers. If a child's legs are so weak and contracted that he crawls along the ground, you must get him walking, because the psychological effect of doing this will be tremendous-his parents will now think that he is worth educating. But if he is an adult, consider his whole future carefully first. He may be able to crawl fast and cultivate his fields on his hands and knees, but if he can only walk slowly and stiffly in calipers, he may die of starvation. So a cultivator may be better crawling, especially if his arms are too weak to use crutches, whereas a clerk, for example, may benefit from calipers. Sometimes an operation is an obvious disseroice, for example lengthening a patient's Achilles tendon, when he walks on the ball of an equinus foot, and this is compensating for a short leg. A severe polio contracture can: (1) cause the skin over a patient's joint to shrink, (2) shorten his muscles, intermuscular septa, nerves, and vessels, (3) contract his joint capsule, (4) deform his epiphyses. Undoing all this is difficult, and may be impossible, so only try to relieve milder contractures, and follow the indications we give carefully, or you may damage important structures, or cause infection or skin loss. A child's contractures are easier to correct than an adult's - he probably only needs a tenotomy - whereas an adult may need an osteotomy, or an arthrodesis. The contractures of a patient's hip and knee, are often associated. You may have to release: (1) His iliotibial band, in several places down his thigh. In a young child, one or two incisions may be enough, and you may not need the complete set of four incisions described below. When you have divided it in his thigh, there may be no need to divide it at his knee. (2)The tight structures on the front of his hip, particularly his iliopsoas. (3) The tendon of his biceps femoris in his popliteal fossa. (4) His medial hamstrings (occasionally). You can cut tight bands and tendons in two ways: (1) You can push a long thin tenotomy knife through a small skin incision, and cut the bands by feel. This is satisfactory for the less severe contractures, provided you do it correctly, and as extensively as necessary.(2) You can cut tight structures under direct vision. In the thigh, this is the best method, especially for severe contractures, but it needs more skill and the wound may break down, so use the closed method. Behind the knee, the common peroneal nerve is very superficial, so the only safe way to divide the tendons there is by open operation. Don't try to treat a contracted hip by manipulation and serial casting in a spica-surgery is better. The knee is the most difficult of the three joints on which you may have to operate, especially in an adult, whose tibia can be rotated backwards and laterally, as well as being flexed. Be safe, and don't try to release a contracture of > 90º. If you try, his tight popliteal vessels and nerves may be stretched; and pain, paralysis, and even gangrene may follow. Even a contracture of < 90° may be difficult. After you have released it as much as you can by tenotomy, you can obtain the final correction by one of these three methods. You can: 1) Manipulate his knee and apply a cast.(2) Apply a cast and wedge it; this may be useful if plaster is scarce, but manipulation and a fresh cast will give better results. A cast by either of these methods will mobilize him earlier, and is economical in the use of beds; but it will not be effective, if the operation has left him with a contracture of 45°, or more. It also increases the risk of a stiff, painful knee, and of osteoarthritis later. (3) Put him into Hamilton Russell traction. This will keep him in bed for 2 or 3 months, but it does have these advantages; (a) it is better if he is an adult, and his contracture is severe, (b) it reduces the risk of pain and osteoarthritis, (c) it is the only way of treating a contracture which remains> 45° after the opera- tion, (d) it helps to control an associated contracture of his hip, (e) it is less likely to cause backward subluxation of his tibia on his femur than extension traction (78.3). Hamilton Russell traction is commonly used for treating fractures of the upper femur and hip, but Perkins traction (78.4) is better and simpler. (4) Use reversed slings on a Thomas splint. (5) Use skeletal traction with a pin through the lower tibia, a simple and very useful method (70.11).
