REST

Since the days of H. O. Thomas (p. 3), who, more than a century ago, emphasised its value in diseases of the spine and limbs, rest has been one of the mainstays of orthopaedic treatment. Complete rest demands recumbency in bed – which, for the most part, is deprecated today – or immobilisation of the diseased part in plaster. But by ‘rest’ the modern orthopaedic surgeon does not usually mean complete inactivity or immobility. Often he means no more than ‘relative rest’, implying simply a reduction of accustomed activity and avoidance of strain. Indeed complete rest is enjoined much less often now than it was in the past, because diseases for which rest was previously important, such as poliomyelitis or tuberculosis, can now be prevented or are more readily amenable to specific remedies such as antibacterial agents. Complete rest after operations, formerly favoured, has given place in most cases to the earliest possible resumption of activity.

SUPPORT

Rest and support often go together; but there are occasions when support is needed but not rest – for example, to stabilise a joint rendered insecure by muscle paralysis, or to prevent the development of deformity. When support is to be temporary it can be provided by a cast or splint made from plaster of Paris or from one of the newer splinting materials. When it is to be prolonged or permanent an individually made surgical appliance, or orthosis, is required. Examples in common use are spinal braces, cervical collars, wrist supports, walking calipers, knee and ankle orthoses, and devices to control drop foot (Figs 11.3–Figs 11.5, pp. 177–8).

PHYSIOTHERAPY

Physiotherapy in its various forms occupies an important place in the non-operative and post-operative treatments of orthopaedic disabilities. Emphasis on evidence-based practice has helped to produce an awareness among physiotherapists of the hazards as well as the merits of treatment. This has led to a correct emphasis being placed upon the value in many conditions of active rather than of passive treatment: in other words, of helping the patient to help him/herself. This approach is particularly rewarding in the rehabilitation of patients after injury or after operations, and in diseases such as poliomyelitis, cerebral palsy, hemiplegia, peripheral nerve palsies and mechanical low back pain. When it is used, physiotherapy should be pursued thoroughly. A number of different physiotherapy interventions have evolved over the years. These may be active, passive or a combination of the two. Passive approaches involve a range of different techniques carried out on the patient by the therapist. Active approaches require active involvement by the patient, either by exercising or changing behaviour.

ALTERNATIVE THERAPIES

There has been an increasing trend for patients to seek alternative therapy (i.e. chiropractic therapy, osteopathy, acupuncture, massage and homeopathy) to relieve musculoskeletal symptoms. However, no strong evidence has emerged over the last decade that suggests that alternative therapy is any more beneficial than physiotherapy.

LOCAL INJECTIONS

The indications for local injections fall into two groups:

The response depends upon the nature of the basic lesion: permanent relief is often gained in extra-articular lesions such as tennis elbow, but in arthritis the benefit is often no more than temporary, and repeated injections are seldom to be recommended.

DRUGS

Drugs have rather a small place in orthopaedic practice. Those used may be placed in eight categories:

Antibacterial agents are of immense importance in infective lesions, especially in acute osteomyelitis and acute pyogenic arthritis. To be successful treatment must be begun very early. These drugs are also of definite value in certain chronic infections, notably in tuberculosis.

Analgesics should be used as little as possible. Many orthopaedic disorders are prolonged for many weeks or months, and it is undesirable to prescribe any but the mildest analgesics continuously over long periods, except for incurable malignant disease.

Sedatives may be given if needed to promote sleep, but as with analgesics the rule should be to prescribe no more than is really necessary.

Anti-inflammatory drugs are those that damp down the excessive inflammatory response that may occur especially in rheumatoid arthritis and related disorders, by inhibiting the cyclo-oxygenase enzymes responsible for prostaglandin formation. Non-steroidal anti-inflammatory drugs are generally to be preferred – especially in the first instance – and they are a mainstay in the treatment of rheumatoid arthritis. Many of these drugs also have an analgesic action. The powerful steroids cortisone, prednisolone, and their analogues should be used with extreme caution and indeed should be avoided altogether whenever possible, because through their side effects they may sometimes do more harm than good. Nevertheless there are times when their use may be justified – as for instance in acute exacerbations of rheumatoid arthritis, and especially in polymyalgia rheumatica and giant-cell arteritis (see p. 166).

Hormone-like drugs include the corticosteroids noted above, and sex hormones or analogues used for the prevention of osteoporosis in post-menopausal women and for the control of certain metastatic tumours such as hormone-dependent breast and prostatic tumours. These are being increasingly replaced by the bisphosphonates, a family of drugs which block the resorption of bone mineral.

Anti-osteoporosis drugs. Hormone replacement therapy and the SERMS (selective oestrogen receptor modulators) have largely been replaced by the bisphosphonates which block bone resorption and by anabolic agents such as parathyroid hormone and strontium.

Specific drugs work well in certain special diseases. Examples are vitamin C for scurvy, vitamin D for rickets and salicylates for the arthritis of rheumatic fever.

Cytotoxic drugs form the basis of chemotherapy for malignant tumours. These anti-cancer drugs include cyclophosphamide, melphalan, vincristine, doxorubicin, and methotrexate. They have serious side effects and are used only under expert supervision.

MANIPULATION

Treatment by manipulation is practised widely by orthopaedic surgeons and by others in allied professions. Strictly, the term might legitimately be used to include the passive movements, or ‘mobilisations’, that form part of the daily activities of a physiotherapy department and which have already been referred to above: but it is used here in a more restricted sense, to describe passive movements of joints, bones, or soft tissues carried out by the surgeon – with or without an anaesthetic, and often forcefully – as a deliberate step in treatment.

The subject will be considered under three general headings:

RADIOTHERAPY

Radiotherapy – by X-rays or by the gamma rays of radio-active substances – may be used for certain benign conditions or for malignant disease. Because of its possible ill effects – particularly the risk of inducing malignant change – it should be advised only with caution for benign lesions, but its use may rarely be justified in the treatment of some cases of giant-cell tumour of bone that are unsuitable for local excision because of their anatomical site. In malignant disease radiotherapy is occasionally curative but more often palliative. In conditions such as malignant bone tumours, for which a tumour dose in the range of 5000–6000 centiGray may be required, only the penetrating rays produced by a super-voltage linear accelerator or by a radio-active cobalt unit should be used. With such apparatus a high dose can be delivered to the tumour with the least possible damage to the skin.

SYNOVECTOMY

Synovectomy is the operation for removal of the inflamed lining of a joint, while leaving the capsule intact. It may be of value in some types of chronic infective arthritis as well as occasionally in early rheumatoid arthritis. Because of the difficulty in gaining anatomical access, it is necessarily a subtotal procedure; but it may nevertheless afford worthwhile relief by reducing local pain and swelling. There is no clear evidence that it protects the articular cartilage from further damage; but the removal of a large part of this invasive granulation tissue or pannus may be of benefit by reducing the production of proteolytic enzymes.

OSTEOTOMY

Osteotomy is the operation of cutting a bone or creating a surgical fracture.

Indications. The general indications for osteotomy are as follows:

In addition, there are certain special indications for osteotomy at the upper end of the femur, as follows:

Technique. If the bone is relatively soft (as in children) it may be divided simply with an osteotome or, in the case of a thin bone, by bone-cutting forceps. The strong cortex of the major long bones in an adult is not easily divided in that way because it tends to splinter; so most surgeons weaken the bone by making multiple drill holes before applying the osteotome, or, alternatively, they use a powered saw or a high-speed dental burr. When the bone has been divided and the necessary correction made it is often convenient to fix the fragments with a plate, nail-plate, or medullary nail: this may allow external splintage to be dispensed with. If internal fixation is not used the fragments may be immobilised by an external fixator; or they may be held in position by a suitable splint or plaster until union has occurred.

ARTHRODESIS

The operation of arthrodesis, or joint fusion, is used less commonly since the advent of reliable techniques of joint reconstruction, or arthroplasty, for the major limb joints. It has the advantage of providing a painless stable joint and the disability from a single stiff joint is usually slight, and patients readily adapt themselves to it. Even when two or three joints are fused function may be surprisingly good, depending upon the particular joints affected. This gives arthrodesis its most common application for treatment of arthritis in the small joints of the hands and feet but it is now rarely used for the hip, knee, or shoulder except as a salvage procedure.

Indications. Arthrodesis is indicated mainly in the following conditions:

Methods of arthrodesis. Arthrodesis may be intra-articular or extra-articular, or the two may be combined. In intra-articular arthrodesis the joint is opened and the bone ends are displayed. The articular cartilage (or what remains of it) is removed so that raw bone is exposed. The joint is placed in the desired position and immobilised, usually by metallic internal fixation as well as by a plaster-of-Paris splint, until clinical tests and radiographs show sound bony fusion. In some cases an external fixation device can be used with the addition of compression across the opposed bone surfaces which seems to speed union.

In extra-articular arthrodesis the joint itself is left undisturbed (though it may be immobilised by a nail or screw), but it is ‘by-passed’ by securing bone-to-bone fusion outside the joint, usually through the medium of a bone graft. The method is applicable mainly to the spine, shoulder, and hip. It has a theoretical advantage in cases of infective joint disease, because any risk of reactivating or disseminating the infection by opening the joint is avoided.

Examples of methods for arthrodesing the spine and a metatarso-phalangeal joint of the toe are illustrated in Fig. 4.1.

Fig 4.1 Two methods of arthrodesis (joint fusion). A Extra-articular arthrodesis of the cervical spine using a posterior cortico-cancellous bone graft with wire fixation, proximal and distal to the intervertebral joint to be fused. B Intra-articular arthrodesis of the metatarso-phalangeal joint of the great toe using internal fixation with a single screw to fix the raw cancellous bone surfaces in the desired position.

Position for arthrodesis. The best position for arthrodesis should not be regarded as rigidly established for each joint: variations may be appropriate and desirable in individual cases – for instance, to conform to the requirements of the patient’s work. The following is only a general guide. Shoulder: 30 ° of abduction and flexion, with 40 ° of medial rotation. Elbow: If only one elbow is affected, 75 ° of flexion from the fully extended position (or according to the requirements of the patient’s work). If both elbows are affected, one should be in flexion 10 ° above the right angle and the other about 20 ° below the right angle. If forearm rotation is lost the most useful position of the forearm is in 10 ° of pronation. Wrist: Extended 20 °. Metacarpo-phalangeal joints: Flexed 35 °. Interphalangeal joints: Semiflexed. Hip: About 15 ° of flexion; no abduction or adduction. Knee: About 20 ° of flexion. Ankle: In men, right angle; in women, 15–25 ° of plantarflexion, according to accustomed height of heel. Metatarso-phalangeal joint of big toe: Slight extension, depending upon the accustomed height of shoe heel.

ARTHROPLASTY

Arthroplasty is the operation for construction of a new movable joint. Its successful development in the last 30 years has resulted from the introduction of new biomaterials to replace articular surfaces and the surgical techniques to attach these to bone. Arthroplasty of the hip has revolutionised the treatment of arthritis in that joint and its use has now been extended to the knee, as well as the ankle, the shoulder, the elbow, certain joints in the hand, and the first metatarso-phalangeal joint in the foot.

Indications. The indications for arthroplasty vary with the particular joint affected and the degree of disability. Broadly, it has a use in the following conditions:

It will be realised that in several of these conditions arthroplasty is an alternative to arthrodesis. By far the commonest applications for arthroplasty are disabling osteoarthritis of the hip and the knee.

Methods of arthroplasty

Three methods are available:

1 excision arthroplasty

2 hemiarthroplasty or half-joint replacement

3 total replacement arthroplasty.

Each method has its merits, disadvantages and special applications.

Excision arthroplasty. In this method one or both of the articular ends of the bones are simply excised, so that a gap is created between them (Fig. 4.2) effectively creating a false joint or pseudarthrosis. The gap fills with fibrous tissue, or a pad of muscle or other soft tissue may be sewn in between the bones. By virtue of its flexibility the interposed tissue allows a reasonable range of movement, but the joint often lacks stability making it less suitable for the large weight-bearing joints of the lower limb. Excision arthroplasty is used most commonly at the metatarso-phalangeal joint of the big toe, in the treatment of hallux valgus and hallux rigidus (Keller’s operation). It is also occasionally used at the hip, usually as a salvage operation after failed replacement arthroplasty. It is used occasionally at the elbow, the shoulder, and certain of the small joints of the hands and feet.

Fig. 4.2 Excision arthroplasty (pseudarthrosis) of the hip. Note the interposed soft tissue between the bony surfaces.

Hemi-arthroplasty (half-joint replacement arthroplasty). In a hemiarthroplasty only one of the articulating surfaces is removed and replaced by a prosthesis of similar shape (Fig. 4.3A). The prosthesis is usually made from metal. When appropriate, it may be fixed into the recipient bone with acrylic filling compound or ‘bone cement’. The opposing, normal articulating surface is left undisturbed. The technique has its main application at the hip, where prosthetic replacement of the head and neck of the femur is commonly practised for femoral neck fracture in the elderly. The disadvantage is that any degeneration in the unreplaced articular surface will accelerate with recurrence of pain and loss of movement making it unsuitable for younger patients. It has rather a limited use elsewhere, examples being the replacement of the head of the radius after certain types of fracture, and replacement of the lunate bone in Kienböck’s disease.

Fig. 4.3 Three methods of arthroplasty (joint replacement) used at the hip. A Half-joint replacement arthroplasty: the femoral head is replaced by a metal prosthesis. B Total replacement arthroplasty. The femoral head is replaced by a metal prosthesis and the acetabulum by a plastic socket. Both components may be held in place by acrylic filling compound or ‘cement’. C Resurfacing (double cup) arthroplasty. Matching metal shells are used to resurface the femoral head and acetabular socket with cemented or cementless fixation.

Total replacement arthroplasty. In this technique both of the opposed articulating surfaces are excised and replaced by prosthetic components (Fig. 4.3B). In the larger joints one of the components is usually of metal and the other of high-density polyethylene, and it is usual for both components to be held in place by acrylic ‘bone cement’. In small joints such as the metacarpo-phalangeal joints a flexible one-piece prosthesis made from silicone rubber may be used.

Total replacement arthroplasty has proved very successful at the hip, and at the knee. It has been extended, so far with only moderate success, to many other joints including the shoulder, elbow, ankle, metacarpo-phalangeal joints, and metatarso-phalangeal joints. A disadvantage – which applies also to half-joint replacement arthroplasty – is that there is a tendency for the prosthesis to work loose after 10–15 years. This results from bone resorption around the implant due to an aseptic inflammatory reaction triggered by the production of microscopic wear particles from the artificial materials used for the articulating surfaces. In turn this has led to a search for harder materials and improved prosthetic designs to minimise the production of wear particles.

Another approach to preserve bone in younger patients, who might require later revision surgery, is to resurface rather than replace the joint. Attempts have been made to achieve this biologically with autogenous chondrocytes in the knee, or with artificial materials as in the double cup arthroplasty of the hip (Fig. 4.3C). The longer-term results from these new techniques remain uncertain and it should be noted that a conventional well-fitted replacement joint may give good service for as long as 15–20 years, especially in the case of the hip or knee.

BONE GRAFTING OPERATIONS

Bone grafts are usually obtained from another part of the patient’s body (autogenous grafts or autografts). If it is impracticable or undesirable to take bone from the patient’s own body, grafts from another human subject may be used (allografts, homogenous grafts or homografts). These must be stored frozen under aseptic conditions until they have been proved to be free from transmissible infection, including HIV and other dangerous viral infections. For bone from living donors (mainly femoral heads removed during hip replacement operations) this necessitates retesting after 9 months to ensure that the donor was not incubating infectious disease at the time of removal of the bone. Cadaveric bone sterilised by irradiation is sometimes used and is increasingly available from large tissue banks. Grafts obtained from animals (xenografts, heterogenous grafts or heterografts) may be applicable if they are specially treated to reduce their antigenic properties. At some centres limited use is still made of such bone (chiefly bovine) prepared commercially in sterile packs, but it has been shown to be far inferior to the patient’s own bone and cannot be relied upon to become incorporated with the host bone.

Bone transferred as a free autograft from one site to another does not survive wholly in a living state. For the most part the bone cells die, although a proportion may possibly survive, especially in cancellous bone. The purpose of the graft – as of allografts and heterografts – is mainly to serve as a scaffolding or temporary bridge upon which new bone is laid down. It also provides an osteogenic stimulus to the host cells from the bone morphogenic proteins released from the non-cellular bone matrix. Thus the whole of a graft is eventually replaced by new living bone. This process of replacement is dependent upon adequate revascularisation of the graft; so a graft that lies in a highly vascular bed is more likely to succeed than one that is surrounded by relatively ischaemic tissue.

With refinements in the technique of microvascular surgery it is now possible to transfer bone with its soft-tissue coverings on a vascular pedicle to a distant recipient site, with immediate anastomosis of its nutrient vessels to those in the new bed. Such living grafts are found to become incorporated rapidly. Vascularised grafts are especially valuable in major reconstructive procedures after extensive loss of bone and soft tissue.

Indications. Bone grafts are used mainly in three types of case:

Technique. Autogenous bone for grafting may be obtained as a solid slab, or it may be used in the form of multiple slivers or strips, or of small chips.

Strut grafts. A strut graft is usually obtained from strong cortical bone: the subcutaneous part of the tibia is a common site. The graft is fixed to the recipient bone either by internal fixation or by inlaying. Such a graft serves as an internal splint as well as providing a framework for the growth of new bone (Fig. 4.4A).

Fig. 4.4 Examples of bone grafting techniques. A Strut graft of cortico-cancellous bone used to provide inlay fixation for anterior cervical spine fusion. B Cancellous grafts used to fill a cavity in a bone. C Vascularised fibula bone graft.

Strip grafts. Sliver or strip grafts are generally obtained from spongy cancellous bone – especially from the crest of the ilium. They are used commonly for ununited fractures. They are laid about the fracture, deep to the periosteum, and are held in place by suture of the soft tissues over them.

Chip grafts. These also are preferably obtained from cancellous bone. They serve the same purposes as sliver grafts but are smaller pieces of bone. The chips are packed firmly into, or around, the recipient bone and are held in place simply by suture of the soft tissues over them (Fig. 4.4B).

Vascularised grafts. These require a suitable donor site, such as the fibula, rib, or iliac crest, together with a meticulous microscopic technique to secure the necessary re-anastomosis of the nutrient vessels at the new site (Fig. 4.4C). The method is only suitable for use in specialised centres with the necessary equipment and expertise.

TENDON TRANSFER OPERATIONS

In the operation of tendon transfer, or tendon transplant, the insertion of a healthy functioning muscle is moved to a new site, so that the muscle henceforth has a different action. In this way the lost function of a paralysed or severed muscle can be taken over by one that is intact. In properly selected cases there need be no noticeable loss of power in the former sphere of action of the transferred muscle, because there is often considerable duplication or overlap in the function of individual muscles. Thus a tendon of flexor digitorum superficialis may be transferred to a new site without appreciably impairing the power of finger flexion, which can be adequately controlled by the flexor profundus. Similarly the extensor indicis can be spared for a new function without seriously interfering with the power of extension of the index finger (Fig. 4.5).

Fig. 4.5 Transfer of extensor indicis to replace a ruptured extensor pollicis longus. This transfer is to be preferred to direct suture when the ends of the ruptured tendon are frayed.

Indications. Tendon transfers have their main application in three groups of conditions:

Technique. The tendon to be transferred is divided at an appropriate point, re-routed in the direction of its new action, and secured to its new insertion. If it is to be inserted into bone it is passed through a drill hole and held by suturing back on itself or by suturing to the periosteum or soft tissues on the deep aspect of the bone. If it is to be united to a tendon stump the junction may be secured by end-to-end suture or, preferably, by interlacing the tendons one through the other and transfixing them with mattress sutures.

Examples. 1. In a case of paralysis of the radial nerve, with loss of active extension of the wrist, fingers, and thumb, function may be restored by the following tendon transfers: pronator teres is transferred to extensor carpi radialis brevis; flexor carpi ulnaris is transferred to extensor digitorum and extensor pollicis longus; and palmaris longus is transferred to abductor pollicis longus. 2. In a case of congenital talipes equino-varus (p. 434) transfer of the tendon of the tibialis anterior or tibialis posterior to the outer side of the foot will help to prevent recurrence of the deformity. 3. In a case of rupture of the extensor pollicis longus, with extensive fraying of the tendon, direct repair may be impracticable. Function may be restored by transfer of the extensor indicis to the extensor pollicis longus (Fig. 4.5).

TENDON GRAFTING OPERATIONS

In tendon grafting a length of free tendon is used to bridge a gap between the severed ends of the recipient tendon.

Indications. The chief use of free tendon grafts is in the reconstruction of flexor tendons severed and adherent in the fibrous digital sheaths of the hand (p. 324).

Technique. The free tendon graft is usually obtained from the palmaris longus or from one of the toe extensors at the dorsum of the foot. The original, adherent tendon is removed. Proximally, the graft is joined to the recipient tendon by sutures of stainless steel wire. Distally, it may be secured to the distal stump of the recipient tendon or it may be attached directly to bone through a drill hole.

EQUALISATION OF LEG LENGTH

If a patient’s legs are of markedly unequal length, as in certain cases of congenital anomaly, previous poliomyelitis, or damage to a growth epiphysis, the discrepancy may be reduced or eliminated by operation. The methods available are:

Leg lengthening is suitable mainly for children. It is achieved by dividing the appropriate bone (usually the tibia, sometimes the femur) and then gradually elongating the limb in a special screw-distraction apparatus at the rate of about 2 mm a day. A maximum of about 5 cm may be gained. The procedure is time-consuming and trying for the patient, and should be reserved for carefully selected cases in which the discrepancy in length is marked. A more recent innovation is the technique of bone transport, in which a length of the diaphysis is moved slowly downwards to fill a gap, while new bone forms to fill in the space created by its advancement (Fig. 4.6). These techniques have been facilitated by the introduction of the ring frame distraction apparatus of Ilizarov¹, which allows correction of angulation as well as lengthening (Fig. 4.7).

Fig. 4.6 The mechanism of bone transport with new bone being formed in a healthy area by distraction.

Fig. 4.7 A Ilizarov frame applied to tibia for leg lengthening. B Radiograph of leg in frame to show position of fixator pins in relation to osteotomy of tibia.

Leg shortening, by removing an appropriate length from the shaft of the longer femur or tibia, is less hazardous but not to be undertaken lightly because it disturbs a limb that was previously normal. In a patient who is fairly tall, and especially in adults, it is often preferable to leg lengthening.

Arrest of epiphysial growth (on the longer side) is applicable only to children with considerable growth still to come. It entails either destruction, or bridging by bone grafts or by metal staples, of the lower femoral epiphysis or of the upper tibial epiphysis, or both. The correction to be expected depends upon the amount of growth still to come from the corresponding epiphysis of the opposite (shorter) leg, which depends in turn upon the patient’s age at the time of operation, and upon the nature of the abnormality that is responsible for the shortening.