Biomedical subjects
Publications and source records attributed to P Laneri.
We have examined the organic components of the nidus of an osteoid osteoma in 4 patients using scanning electron microscopy. Different organisation of the osteoblastic cells and of the fibrous structures of the osteoid matrix in different zones was demonstrated. These findings indicated a greater degree of immaturity in the centre, as compared with the peripheral area where the process of differentiation was more evident.
Taking advantage of the observation of 2 instances of intradural disk herniation, the authors examine the pathogenetic, clinical, diagnostic, and therapeutic aspects of this rare occurrence in light of a review of the literature and their own observations. Of the theories as to the cause of the syndrome, two appear worth noting: the relative immobility of the dural sac, bound by the surrounding nerve roots; the inflammatory and cicatricial adhesions that establish themselves between the posterior longitudinal ligament and the dural sac. The clinical features as well as the laboratory and diagnostic tests suggest compression of one or more nerve roots similar to that caused by other intradural expansion processes. The onset can be sudden and acute or delayed depending on whether the dural sac adhesions were present before disk herniation or appeared at a later stage. Intradural disk herniation must be checked for, often intraoperatively, in all cases of radiculopathy due to intradural compression. Error in the assessment of the level of the lesion, concomitant extruded extradural disk herniation, or failure to recognize the immobility of the dural sac can all lead to misdiagnosis of intradural disk herniation if the search for this syndrome is not correctly carried out.
The good results achieved with osteotomy in the treatment of arthritic varus knee lead the authors to pinpoint some frequently controversial aspects that are important for the attainment of an excellent outcome. The study consisted of 46 patients, each subjected to valgus osteotomy. The site of the tibial osteotomy should be above the insertion point of the patellar tendon in order to better guarantee stability and healing. For mechanical reasons, high metaphyseal peroneal osteotomy is preferred over other methods such as diaphyseal osteotomy, excision of the peroneal head, and proximal tibioperoneal syndesmotomy. Both osteotomies can be done through a single anterolateral incision, without risking injury to the lateral popliteal sciatic nerve. The preferred method of osteotomy is to cut a noncuneiform linear rima with the osteotome and perform the angular correction at the joint of the metaphyseal spongy bone. The osteotomy is then stabilized with staples and a cast for a period of 40 days. Overcorrection past the physiological valgus deformity is necessary in order to move the weight-bearing axis onto the lateral hemirima; the degree of surgical correction should be calculated on the basis of orthostatic radiographs. Good clinical results are always accompanied by the following radiographic developments: opening of the medial articular hemirima, improvement of the subchondral bone sclerosis, and reappearance of the outlines of both the spongy bone and the subchondral bone lamina; all these are signs of good bone adjustment made possible by the reinstatement of mechanical equilibrium in the knee.
The authors report the results of automated percutaneous diskectomy in the treatment of the herniated disk. During an 18-month period this procedure was used on 39 patients with both evident radicular pathology that had not regressed even after 4-6 weeks of medical and physical therapy as well as clear disk herniation revealed by diagnostic imaging. The level of the herniated disk was L4-L5 in 30 cases. L5-S1 in 7 cases, and L3-L4 in 2 cases. The clinical diagnosis was confirmed by CAT scan in 20 cases, by both CAT scan and x-ray of the spinal region in 14 cases, and by x-ray only in 5 cases. The patients were reviewed 2, 6, and 12 months after surgery. The results were classified according to Watters' criteria based on both the relief of pain and the resumption of everyday work activity. The satisfactory results (excellent and good) totaled 59% at the 6-month follow-up, with no substantial variation at the 1-year follow-up. Hemilaminectomy was performed in 12 cases with unsatisfactory results, confirming the diagnosis of disk herniation in 10 cases (extruded in 9 cases and protruded in 1 case). Diskectomy is a non-invasive, atraumatic method which is indicated for both protruded (non-sequestrated) and subumbilical hernias and allows rapid functional recovery. The rate of success can be increased with more accurate selection of patients based on imaging diagnosis (CAT scan and MRI).