Motor evoked potentials in the post-surgical follow-up of cervical spondylotic myelopathy.

Eighteen patients (6 female, 12 male; average age 51 years, range 37-79) with clinical and radiological evidence (MRI) of cervical spondylotic myelopathy (CSM) were examined. The subjects were divided into two groups depending on whether radiology indicated single level (9 patients) or multilevel (9 patients) compression of the cervical cord. All of the patients underwent surgical decompression. Seriate exam with trans-cranial magnetic stimulation was performed in double session before surgery, and 3 and 12 months after surgery. The follow-up study of these patients revealed a statistically significant neurophysiological improvement only in those patients with single-level compression. In these cases, the cervical cord pathology revealed by MRI signal hyperintensity in T2 may at least partially consist of an edematous component and/or an initial demyelinization that has still a chance of recovery. In patients with multilevel damage, the compression may cause irreversible lesions.

Usefulness of motor evoked potentials in compressive myelopathy.

Motor Evoked Potentials elicited by transcranial magnetic stimulation were recorded from 1 degree Dorsal Interosseus for the upper limbs and from Extensor Digitorum Brevis for the lower limbs in 42 subjects with compressive myelopathy (36 in the cervical region and 6 in the dorsal region), radiologically defined by Nuclear Magnetic Resonance (NMR) imaging, with no clinical and radiological signs of radiculopathy. Central motor conduction abnormalities in the cortex-C8 and cortex-L5 tract were compared with clinical signs of motor impairment and with NMR findings. The subjects with medullar hyperintensity of NMR signal at the compression site level, showed a central conduction time (C.C.T.) prolongation in at least one side in the 70% of cases in the cortex-C8 tract and in the 95% of cases in the cortex-L5 tract, while in the cases with no compression site alterations of signal, C.C.T. abnormalities were observed only in 25% in the cortex-C8 tract and in 42% in the cortex-L5 tract. In 12 subjects (10 with cervical compression and 2 with dorsal compression) we compared Motor Evoked Potentials before, two weeks and two months after surgical decompression. The C.C.T. cortex-C8 and cortex-L5 improved at least in one side in 11 out of the 12 subjects, showing a good correlation with clinical recovery. In the examined patients we found a latency reduction statistically significant between the first and second investigation, with a trend to stabilization in the following controls.

Lumbar stenosis surgery: "recalibrage" according to Senegas.

In the treatment of lumbar stenosis the method known as "recalibrage" proposed by Senegas is the most recent alternative to extended traditional laminectomy. Posterior decompression, which is obtained by removal of the cephalic half of the laminae, the yellow ligaments and the intraforaminal part of the facet joint, reduces the risk of postsurgical instability and makes it possible to proceed with fusion which is not just posterolateral. In cases where there is intersegmental instability we applied the Hartshill rectangle, proposed by Doce, stabilized to the residual laminar and associated with genous grafting. Our experience is based on 48 cases treated with this method over the last three years. In 19 cases Hartshill fixation was used to complete "recalibrage". Results are generally satisfactory, although follow-up is short. The "relative gain" method proposed by Lassale and Garcon was used for evaluation.

Automated percutaneous lumbar diskectomy according to the Onik method: conclusive considerations.

The Onik method of automated percutaneous diskectomy in the treatment of the herniated lumbar disk offers undeniable advantages which we have already elaborated in our preliminary studies. Nevertheless, further experience with this technique has allowed us to pinpoint several aspects worthy of more attention: patient selection and long-term results. The patient selection procedure must follow Maroon and Onik's original protocol to the letter in order to single out those patients in whom contained disk herniation has caused actual sciatic pain and not merely low back pain. Imaging tests such as CT scan, MRI, and myelography have proved useful mainly in identifying contraindications for the technique, while only intraoperative diskography has been capable of diagnosing the contained status of the disk herniation, the basic criterion for selection. We reviewed 98 automated percutaneous lumbar diskectomies after a follow-up period ranging from 6 months to 2 1/2 years and found the results to be satisfactory, in spite of a slight deterioration of the good results at 6-9 months, following which there was no further change.

Arthrography of the prosthesetized painful hip: the importance of imaging and functional testing.

Thirty-four patients with painful prosthesetized hips were submitted to arthrography in order to evaluate the correlation between pain and the anatomical situation between the implants and the host bone. By injecting a local anaesthetic together with the contrast medium it was possible to perform functional tests comprising passive movements of the hip and full weightbearing for at least 5 minutes in order to ascertain whether or not the pain persisted. This yielded different results varying from total relief to persistence, depending on the type of mobilisation demonstrated by arthrography. In particular, pain was reduced in cases of mobilisation of the acetabular component, and persisted when mobilisation was in the femoral component. A correlation between functional testing, arthrography and bacteriological examination for possible low grade infection allowed for a closer study of the origin of pain, and more accurate planning of surgery when re-prosthesetization was being considered.

Percutaneous lumbar nuclectomy according to the Onik method: indications, technique, first results.

The authors report their first experience with 20 cases of lumbar herniated disc treated by percutaneous nuclectomy according to the Onik method. The methods used for a precise preliminary assessment of the prolapse in order to establish correct indications are discussed. The technique of the operation is then described. The simplicity and relative absence of trauma in this type of surgery, associated with the patient's rapid recovery, drastically reduces hospitalization time, with consequent social and economic advantages. The clinical results at follow-up are sufficiently rewarding to suggest a wider use of this method, but it is essential to restrict it to the indications laid down, which are fully illustrated. The method is applicable only to contained hernias and is contra-indicated in extruded hernias.

The surgical treatment of metastatic tumours of the lumbar spine.

Thirty-three patients affected by metastases in the lumbar spine were treated surgically with the objective of stabilising the affected area while at the same time alleviating involvement of the neurological structures. The surgical technique was adapted to the type and site of the lesion. The lumbar spine differs from the dorsal and cervical spine in that there are two quite different levels of neurological risk above and below L2. Above L2 it is severe, of rapid onset, and usually irreversible. Below L2 it is more easily reversible, even if surgical intervention is not carried out immediately. In cases with neurological involvement, the results were always very much better in the cases operated on early. This led us to carry out the operation prophylactically with rewarding results because none of these patients subsequently developed neurological damage.

Retrosternal dislocation of the clavicle. Observations on three cases.

The writers report three cases of retrosternal dislocation of the clavicle which exemplify the three fundamental anatomical variants and the consequent different therapeutic approach. A review of the literature indicates that this condition is extremely rare, although it may sometimes be related to severe and even fatal complications.

Surgical management of spinal cord lesions due to metastases.

The authors having operated on 358 cases of metastatic lesions, 112 involving the spinal cord, explain their aim and surgical techniques. The importance of an early operation is emphasized. The main purpose is to improve the quality of the patient's life.