As everybody knows, cervical arthrosis is a very frequent disease: approximately 10% of adult or elderly population is affected by it, and in a number of cases severely.
It is worthwhile pointing out from the very beginning that, since this is a degenerative pathology, it should somehow be viewed as an inevitable aging process of the vertebral structures. Indeed, it is almost impossible not to find arthrosic processes, to a larger or smaller extent, in the cervical column of any person who is over the age of 50. It should also be stressed that this pathology is often triggered off or worsened by certain professional activities. But luckily most people suffering from cervical arthrosis do not display neurological symptoms, which means that the ossifications produced by arthrosis in the vertebrae do not cause a compression of the nervous structures (nerve roots or marrow). This is the key to a correct approach to the treatment of cervical arthrosis: the specialist should be in a position to properly assess, for each individual patient, on the basis of any clinical test which might be required, if a neurological compression exists: that is if arthrosis has generated a local stenosis such as to cause a nervous compression. In these cases, only surgery can solve the patient’s problems and, what is even more important, in certain cases prevent the situation from inevitably and dramatically worsening. Lastly, it is these very cases that, if not selected early enough, may involve an aggravation of the neurological symptomatology as a result of physiotherapy. It is not always easy to differentiate between surgical and non-surgical cases, but it is essential from a prognostic point of view. To this end, specific competence in the field of cervical pathology and surgery can help and this is the reason why these patients should be addressed to centres which a expressly qualified for the purpose. The degenerative pathology affects the cervical rachis (Fig. 1) at a median/low level (from C3 to C7) and almost always spares the higher levels (occipital area – C1-C2), which are only affected by degenerative processes as a result of mechanical overloads brought about by congenital malformations. Arthrosis in the cervical area reveals itself with clinical symptoms that sometimes request surgical treatment, resulting from its localisation within the disc intersomatic articulation area and from vertebral body deformations, whereas localisation in the interapophyseal articulation area hardly ever involves a need for surgical treatment. Arthrosic osteophytic deformation of the epidisc body surface may cause clinical syndromes brought about by the compression of the structures near to the vertebral body. (Fig. 2 and 3) As a rule, we could state that intersomatic arthrosis can result in 4 types of osteophytic compression: anterior (rare), lateral, posterolateral and posterior. These generate 4 different clinical syndromes, which however may occasionally coexist when the ostephytosis is larger or circumferential. An accurate identification of any of these four syndromes will be sufficient for us to assess which and where the compression is and therefore, with the aid of CAT and NMR, it will address as to the required surgical action (TAB. I).
1) Cervical intersomatic arthrosis may easily cause the formation of anterior osteophyte protrusions, which occasionally prove very evident under examination; however such deformations rarely lead to an actual dysphagic syndrome caused by esophageal compression and demanding surgical ablation. Of course, indication for surgery, which as mentioned is rather rare, is preceded by radiologic examination of deglutition through videofluorografy and the surgical action (osteophytectomy), through an anterior pre-sternocleidomastoid approach, is simple and rapid.
2) On the other hand, a distinctly lateral deformation of the intersomatic joint (Fig. 4) brings about ostephytosis on a specific joint, which is called uncal joint. Uncoarthrosis results in a compression of a vertebral artery segment (Fig. 5) which, being contained in the intertransverse vertebral foramen, cannot avoid such a compression and brings about a complex syndrome, called uncoarthrosis-related vertebrobasilar insufficiency syndrome. (Fig. 6) This syndrome manifests itself with headache, nausea, vertigo, tinnitus, scotomata, memory disorders, difficulties in concentration, confusion, etc. It is very frequent and it chiefly triggers off as a result of head rotary motions or of head hyperextension (such as when shaving, or engaging the reverse gear or looking upwards when placing something on a cupboard shelf). In most cases, this is only an irritative pathology of the perivertebral orthosympathetic nervous plexus relating to the vertebral artery, which will therefore require medical, and not surgical, treatment. But in a certain percentage of cases, when this clinic syndrome exists without intrinsic otovestibular-related syndromes which may simulate a similar symptomatology, and, above all, with an arteriographic confirmation (Fig. 7 and 8) of the extrinsic compression of the vertebral artery by the uncoarthrosic deformation, indication for surgery exists, with the purpose of freeing the vertebral artery, according to the Jung techniques. These consist in reaching the vertebral surface through an anterior pre-sternocleidomastoid approach to the neck, in removing the part of the transverse which anteriorly closes the intertransversal canal (transversectomy) (Fig. 9) and subsequently, after having moved aside the vertebral artery, in removing the uncal osteophytic deformation compressing the artery (uncusectomy) (Fig. 10). This operation, which is very difficult and complex from a technical-surgical point of view, is however very well tolerated by the patient, it does not involve a long convalescence and above all leads to an immediate disappearance of the symptoms, with great satisfaction of the patient.
3) In the cases in which the mass of the osteophyte, departing from the surface of the disc body, mainly develops in a posterolateral direction (Fig. 11), there is a narrowing of the intervertebral foramen with a severe compression of the root (Fig. 12): this causes a characteristic radiculopathic syndrome, which differs of course depending on the radicular level concerned and, from a clinical point of view, involves a radiculopathy-level diagnosis. In any case, the diagnostic stage should be accurately completed with CAT and/or NMR, and very often with electromyography, in order to ascertain the exact area and extent of the compression; in addition it is advisable to undergo an adequate period of medical therapy (rest, non-steroid anti-inflammatory agents, neurotrophic agents, cortisonic agents) and physical therapy (massotherapy, mild gymnastics), but never manipulations. In many cases the brachialgia, which is particularly unpleasant for the patient, disappears after a few months. In the cases in which compression causes a radicular damage that resists medical treatment, it is necessary to carry out a radicular lysis operation by means of posterolateral osteophytectomy (Fig. 14). This osteophytectomy is carried out with a transdisc anterior approach (Fig. 13) and is combined with intersomatic arthrodesis following complete discectomy. This surgical technique, besides enabling transdisc removal of the osteophyte, enables a certain diastasis between the two vertebral metameres, with consequent widening of the intervertebral foramen through which the compressed root passes. The intersomatic arthrodesis technique offering greater guarantees as regards consolidation and duration of the intermetameric diastasis, is the one performed according to the Robinson technique, whereby tissue is taken from the iliac crest, it is adequately shaped and is then fitted in the disc space prepared for the arthrodesis. (Fig. 15, 16, 17, 18). The old arthrodesis according to the Cloward technique, with bicortical graft taken from the iliac wing, has often displayed unpleasant inconveniences with arthrodesis consolidation resulting in kyphotisation. After the arthrodesis with osseous graft, it is optional to also accomplish a fixation with plate and screws. This may depend on the surgeon’s practices, on the extemporaneous solidity of the osseous graft, on the quality of the bone itself (osteoporosis) or on whether external immobilisation after the operation is possible. Out of over 800 Robinson technique operations carried out without the plate, we have always obtained a good fusion of the graft, but we have always applied a plaster or orthopaedic brace for 2 months. In the cases in which intolerance could be expected (elderly, obese, psychiatric patients, etc.) we have also accomplished a fixation with a plate. (Fig. 19). Over the most recent years, intersomatic arthrodesis is increasingly often carried out with cages in various materials (titanium, carbon), in various shapes and sizes, with different implantation techniques, filled with a greater or smaller number of autologous or heterologous fragments of osseous tissue, again with the purpose of relieving the patient from external post-operative immobilisation. We apply the BAK C system with full satisfaction. (Fig. 20). After 3 days the patient is discharged from hospital and may resume his/her activity without having to wear an external brace. (Fig. 21)
4) When the stenosis caused by osteophytic compression of the somatic surface mainly develops centrally, the resulting compression of the cervical marrow generates a myelopathic syndrome (Fig. 22 e 23). This syndrome always progresses over time. Therefore in such cases indication for surgical decompression should not be given when the symptom cohort is already evident, with clones, Babinski, ataxospastic walking, hyperreflexia of the lower limbs, but much earlier than these symptoms become evident, therefore as soon as initial signs of medullar suffering appear, thus suggesting the existence of medullar compressions. Initial disorders in walking, a sense of weakness of the lower limbs, difficulties in climbing the stairs after a few steps, calf cramps after walking a few metres, are all signs which demand in-depth diagnostic checks, such as CAT, NMR, electrophysiological tests with evoked potentials. Once indication for surgical treatment of the myelopathy has been assessed, it is necessary to establish which and how many osteophyte levels are causing the stenosis with medullar compression. The following conditions may materialise: stenosis at one level only, stenosis at several contiguous levels and stenosis at several non-contiguous levels. In the event of compression at one level only, the operation is not very dissimilar from the one performed in treating a radiculopathic syndrome, in that it involves carrying out, after a discectomy, the transdisc removal of the osteophyte (with a curved spoon-shaped tool, or with a clamp or bur) which in this case will have mainly developed posteriorly, after which the surgical operation is completed with an intersomatic arthrodesis according to the Robinson technique, or with a cage (BAK). In multi-level ostephytosis it is necessary to assess whether the cervical lordosis has been preserved or has even increased. (Fig. 24) In these cases it is possible to adopt a posterior approach (Fig. 25), by carrying out laminectomies, and in special way the Aboulker laminectomy. This is a complete laminectomy, extending upwards and downwards, from C1 to D1-D2 and sideways up to the interapophyseal joints, which however have to remain intact. In this way, since the lordosis is cervical, the marrow, which is no longer hindered by the posterior laminar structures, is free to move backwards (Fig. 26), as if it were the string of an ideal bow, the cervical column, and in this way it becomes detached from the posterior surface of the vertebral fields where it undergoes the compressive effect of the intersomatic osteophytes. (Fig. 27). This plain laminectomy technique does not involve particularly severe consequences for the patient, who regains a reasonable amount of autonomy within a few a months. Based on the review of 100 cases treated with surgery in over 10 years, we have found that good results are maintained in over 80% of cases; only in 20% of cases has there been, over the years, a slight worsening in the lower limb neurological picture: it should be stressed that all these cases had reached the surgical stage belatedly, and already displayed clear neurological disorders before the operation. This therefore confirms the need for diagnosis and surgery to take place as early as possible. As an alternative to this plain laminectomy technique (Aboulker technique), the “open-door” laminectomy technique can be adopted to posteriorly decompress the marrow (Fig. 28): this procedure does not involve the removal of the laminae for each vertebra, but consists in their unilateral section and hence in opening them altogether, as if opening a door. This technique, which was first devised in Japan, has undergone over time a number of variants, but the basic concept is always that of decompressing the marrow without removing the laminae. The results may be compared to those of total laminectomy, but we have found the surgical technique more difficult and laborious. On the other hand, when the cervical lordosis in not preserved, and there is a straightening, or even an inversion, with lordosis changing into kyphosis, it is not of course conceivable to detach the marrow from the ostephytosis by taking advantage of the “bowstring effect”, which can be obtained with a laminectomy, and it is therefore necessary to go back to an anterior approach. If the stenosis of the canal is brought about by a number of osteophytes at non-contiguous levels, the operation to be chosen is the above-mentioned transdisc osteophytectomy and arthrodesis according to the Robinson technique, repeated at all the levels at which compression exists (Fig. 29 and 30). On the other hand, when the stenosis is due to ostephytosis at contiguous levels, rather than implementing several Robinson arthrodesis operations near to each other, it is advisable to implement not only transdisc osteophytectomy, but a corporectomy of the vertebral body or bodies existing between the contiguous compression levels, until complete decompression of the marrow is achieved, and then restore column stability by means of a single long tricortical osseous graft fitted in the entire area involved by the corpectomy, if necessary with the aid of a metal cage in titanium. However, only just recently, a new technique without graft, called free-corpectomy, is being improved. Indeed, it is now acknowledged that intersomatic arthrodesis generates a dynamic overload on intervertebral discs situated above and below the arthrodesis area, thus bringing about at a later stage new and serious disc alterations at such levels. Of course, this overload is even worse in the event of an extended multi-level arthrodesis area. For this reason, an attempt has been made to prevent this mechanical overload by avoiding the resort to the osseous graft. (Fig. 31, 32, 33, 34) Obviously, to avoid destabilising the cervical vertebral structures, the free-corpectomy operation can only be carried out subject to the following two prerequisites: absolute respect for the anterolateral part of the intersomatic joints represented by the uncal joints (which means a posterior trapezoidal corpectomy is carried out) and pre-operative and intraoperative checks (through dynamic radiographic controls of the cervical rachis) as to the existence of any rigidity within the interapophyseal joints. In this limited range of cases, therefore, free-corpectomy appears to offer the undoubted advantage of preventing the development, over time, of articular overloads in the areas neighbouring the arthrodesis and of also preventing post-operative plaster immobilisation, which is often required after an intersomatic arthrodesis. In addition to what has been said so far with respect to individual syndromes deriving from intersomatic arthrosic ostephytosis, we obviously need to take into account that, in the event of broader ostephytosis, causing at the same time a compression on the vertebral artery and on the nervous root, or on the nervous root and on the marrow, or even on all three at the same time (Fig. 35), it may become necessary to carry out a decompression of all these elements at the same time, by adopting an anterior approach and completing the operation with an intersomatic arthrodesis.
5) In fewer cases, interapophyseal arthrodesis, that is arthrodesis involving the posterior joints, may generate a form of ostephytosis resulting in the narrowing of the intervertebral foramen (Fig. 36) and hence a radiculopathic syndrome demanding a relief of the nervous root, through osteophytectomy and partial interapophyseal arthrectomy, with a posterolateral approach according to the Frikolm technique. (Fig. 37)
CONCLUSIONS
Cervical arthrosis, with the formation of osteophytic protrusions developing in various directions, undoubtedly is the most frequent cause of stenosis of the vertebral, intervertebral or transverse canal. Very often, this situation develops within a spinal canal that is already congenitally narrow (8% of population). However, we would like to stress a very important concept: there is no correlation between the extent of the osteophytic formation and the patient’s complaints. We daily see CAT and NMR pictures of cervical rachises full of osteophytes and narrowings of the vertebral canal, in absolutely asymptomatic patients. Such cases should not be approached surgically, but should only be regularly monitored. It is imperative for the specialist to combine examination of the patient’s clinical picture with that of the imagining report (X-Rays, CAT, NMR): we are to treat the patient, not the test. Only when a correlation exists between the clinical report (above all the neurological picture) and imaging, should indication for surgery be put forward. At this point we also need to point out that many of such patients, even though displaying symptoms, partly or fully solve their problems without the need of surgery. An adequate medical and physiotherapeutic treatment may certainly solve a great part of branchial radiculopathies. We are however alarmed by the really superficial abuse of cervical manipulations or tractions. Suffice it to mention the case of a large osteophyte of the uncus compressing a vertebral artery, or that of a large stenosis of the canal with medullar compression that does not display symptoms yet: how can we not take into account the possible damage resulting from the repeated friction of the osteophytes on the compressed structures? Although we have expressed and recommended caution in addressing cervico-arthrosic patients to surgery, there is one case in which we definitely recommend early surgery: that of patients affected by canal stenosis resulting in myelopathy. Medullar compression should be immediately relieved: any time spent waiting or on physiotherapy is wasted. The efficaciousness of the operation depends on its precocity. Having established this principle, we have amply described how the operation should be planned, depending on the individual patient’s clinical picture (TAB. I) and on the situation of his/her cervical column. In this type of surgery, it is necessary to be schematic and to take a correct view of how to proceed: there are no alternative approaches, either anterior or posterior, but specific indications to adopt one approach or the other. Only in this way is it possible to obtain good results in a pathology which is often severe for the patient, but which in most cases can be successfully dealt with.
Antonio Solini
Primario Ospedale Molinette - Torino Centro Studio e Chirurgia del Rachide Cervicale Divisione di Ortopedia e Traumatologia
