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Biomedical subjects

J Cañadell

Publications and source records attributed to J Cañadell.

At least 19 recordsLinked to original sources

Soft tissue behavior during limb lengthening: an experimental study in lambs.

The effect of femoral elongation on skeletal muscle, nerves, and vessels was studied. Three groups of five lambs were used. After the intervention, the animals were killed at 2, 3, and 4 months. A left femoral elongation of 6 cm was practiced on all of them by means of callotasis, with a distraction rate of 0.5 mm every 12 hours. The femoral elongation process was evaluated by monthly x-ray films. The nucleic acid and protein levels in the muscular tissue were quantified at the level of the elongation focus and in the control extremity. The motor conduction velocity of the sciatic nerve was measured in both posterior limbs before the intervention and immediately before the lambs were killed. The arterial blood flow of both subsequent extremities was measured at the moment of death. A histological study of quadriceps muscle, sciatic nerves, artery, and subsequent femoral vein were examined histologically at the level of the elongation focus of both extremities. After elongation, no significant differences were observed in the muscle protein and nucleic acid levels with respect to the control extremity. No significant changes of the nerve conduction velocity were observed in any animal among the different groups. The arterial blood flow of the elongated extremity showed a progressive increase, reaching its maximum value 1 month after the distraction had terminated, with subsequent normalization. This increase of the blood flow was also observed in the control extremity, suggesting a possible systemic effect. The histological study revealed a comparative thickening of the endomysium and perimysium in the elongated muscle tissue, present at the end of the distraction and which was later normalized. No histological changes of the nerve stems undergoing distraction were observed either. During elongation, the arteries showed minimal histological changes. On the other hand, the veins showed areas of endothelial damage accompanied by thrombosis phenomena, especially at the end of the distraction period. The vascular morphology presented progressive normalization after the distraction phase.

Animals

Consolidation of massive bone allografts in limb-preserving operations for bone tumours.

This study analysed the influence of several factors affecting the consolidation time of 83 massive bone allografts in 79 patients with malignant bone tumours: osteosarcoma 57; Ewing's sarcoma 8; malignant fibrous histiocytoma 3; chondrosarcoma 4; fibrosarcoma 5; and giant cell tumours 2. The mean age of the patients was 19 years and the mean length of the allografts was 18 cm. The minimum follow up was for 12 months. The mean consolidation time for metaphyseal and diaphyseal osteotomies was 6.5 and 16 months respectively. Fifteen diaphyseal osteotomies required autologous cancellous grafting. There were 8 allograft fractures after consolidation. The following factors which might influence consolidation were analysed: age of the host and donor; allograft length and site; type of osteotomy and osteosynthesis; intra-arterial and systemic chemotherapy; intraoperative and external radio-therapy. In diaphyseal osteotomies there were statistically significant differences in consolidation time with the use of systemic chemotherapy, external radiotherapy and the recipient's age.

Adolescent

Complications of bone lengthening.

Bone lengthening is a surgical method which requires meticulous technique, continuous attention, and satisfactory cooperation on the part of the patient. The absence of common criteria makes it difficult both to classify the complications which arise, and to compare them with those of other authors. We report the complications in a group of 61 patients who were studied prospectively. Disorders of the lengthening callus accounted for 45% of all complications, and a further 33% arose in the joints. The remainder occurred in the bone, the apparatus and the soft tissues, of which the most common were stiffness of the joints, axial deviations and loosening of the pins, while articular subluxation, fractures with angulation and delayed consolidation occurred less frequently. In our study, the overall number of complications per lengthening process was 2.1. In bilateral lengthening, the rate was 1 per segment, while in unilateral cases the mean was 2.7. Problems which we defined as severe, requiring that the lengthening had to be halted, occurred in 1.8% of the total complications. The aetiology of the length discrepancy has an important role in the complications which occur in each segment. Over twice as many problems occur in asymmetrical lengthening procedures as in patients where lengthening is symmetrical.

Bone Lengthening

Biopsy technique in the treatment of osteosarcoma.

Seventy-eight consecutive patients with stage IIB osteosarcoma of the appendicular skeleton, treated between 1982 and 1992, were studied to determine whether the technique of biopsy affected the prognosis for long term survival. The risk of local recurrence was significant (p < 0.02) after open biopsy, as was the poor response to chemotherapy (p < 0.05) after percutaneous biopsy. We recommend percutaneous biopsy, if possible, when an osteosarcoma is suspected.

Adolescent

Intercalary bone allografts. 23 tumor cases followed for 3 years.

From 1987 to 1991, 26 patients with malignant bone tumors (osteosarcoma, Ewing's sarcoma, chondrosarcoma and malignant fibrous histiocytoma) in the diaphysis or metaphysis of long bones have been treated by chemotherapy, radiotherapy and intercalary bone allograft replacement after resection. The mean follow-up was 3 years in 23 patients, 2 died from tumors, and 1 had an amputation because of local recurrence. Allograft incorporation in 11 metaphyseal anastomoses was excellent in all cases. In the 23 diaphyseal anastomoses there were 6 non-unions. Other complications were deep infection in 3 cases, leg length discrepancy in 2 and allograft fracture in 2. Function became satisfactory in 14 cases.

Adolescent

Large experimental segmental bone defects treated by bone transportation with monolateral external distractors.

Monolateral frames were applied to five dogs and ten lambs for treatment of large segmental bone defects (LSBD) surgically induced in one of their femoral diaphyses. Reconstruction was attempted by bone transport, as developed by Ilizarov. Monolateral frames were used to minimize the draw-backs of Ilizarov's circular device. Radiographic, computed tomographic, and histologic studies were performed. The skin and soft tissues were not a major obstacle for the longitudinal migration of the screws during bone transport. Four months after the operations, healing and remodeling of the bone defect was always satisfactory. Histologically, the repair of the lengthened segment followed an intramembranous ossification pattern in its central areas and in the periphery as well. At the end of the experiment, the new induced bone had a virtually normal diaphyseal bone appearance. Bone transport for the treatment of experimental LSBD can be completed in monolateral frames.

Animals

Removal of metaphyseal bone tumours with preservation of the epiphysis. Physeal distraction before excision.

In immature long bones, radical excision of malignant tumours of the metaphysis may necessitate sacrifice of the adjacent epiphysis. To preserve the adjacent joint while allowing a safe margin of excision, we used physeal distraction before removing the tumour. From July 1984 to August 1992, we operated on 20 patients by this method. After a mean follow-up of 54 months there was no local recurrence in the epiphyseal region. Three patients had developed pulmonary metastases.

Adolescent

Arthrodiastasis for stiff hips in young patients.

Joint distraction (arthrodiastasis) with a unilateral fixator was used to treat 9 patients with stiffness of the hip which had followed Perthes' disease (3), epiphysiolysis (2), congenital dysplasia (2), tuberculosis (1) and idiopathic chondrolysis (1). Their average age was 14 years, and they all had pain, limp and shortening of the leg. Distraction of 0.5 to 1 cm was maintained for an average of 94 days. The average range of movement subsequently was 65 degrees compared with 20 degrees before. The articular space was widened by an average of 2.8 mm, and only 3 patients had pain on follow up.

Adolescent

[Role of conservative surgery in the multidisciplinary treatment of Ewing's sarcoma in childhood].

BACKGROUND: In order to cure Ewing's sarcoma it is necessary to have an approach which considers the radical local control on the sites of macroscopic disease, along with the systemic control of micrometastases. On the present study the experience of the authors in analyzed, remarking the role of cytoreduction surgery on curability. METHODS: From January 1982 to August 1991, 24 patients with the mean age 13 years, 14 boys and 10 girls, previously untreated and with a pathology proven diagnosis have been treated by the authors. The treatment protocol included: alternating chemotherapy with cyclophosphamide, adriamycin, methotrexate, bleomycin, actinomycin D and vincristine; administered simultaneously with preoperative external radiation with a volume that completely included the affected bone and surrounding soft tissues for a total dose of 45 Gy/4.5 weeks. After a resting period of 4 weeks, resection of the involved bone and adjacent healthy bone was performed, followed by a single dose of 10-15 Gy of intraoperative radiotherapy to the tumor bed. Subsequently a custom prostheses or allograft was implanted. RESULTS: Twenty patients had localized disease and 4 had metastatic disease at diagnosis. In 16 cases the tumor was in extremities, 5 axial, and 3 extraskeletical. In 15 patients surgery with limb sparing techniques was performed, 8 had en block resection and one amputation (calcaneous location). At the time of this report 21 patient are alive (87%). Four had disease progression, of this 3 had died (12%). The actuarial disease free survival rate is 80% +/- 9% with a follow-up of 104 months, being the mean survival time of 85.5 months. CONCLUSIONS: The cytoreduction surgery included into a multidisciplinary approach permits to achieve a high rate of cure in Ewing's sarcoma. The toxicity of the program can be considered acceptable.

Actuarial Analysis

Delayed distraction in bone lengthening. Improved healing in lambs.

We compared delayed distraction (DD) with immediate distraction (ID) in bone-lengthening. Open femoral diaphyseal osteotomy was performed on 24 three-month-old lambs, and external distractor fixators were applied. In the ID group (n 12), distraction commenced on the first postoperative day; in the DD group (n 12), distraction was delayed until the tenth day after surgery. In all the animals, the femur was lengthened by 2 cm at the rate of 1 mm/day. The animals were killed 1, 2, and 3 months postoperatively. Radiography and densitometry of the lengthened callus showed that DD, compared with ID, improved the quality of the callus with quicker, denser, and more homogeneous bone formation.

Animals

Lymphocyte response to polymethylmethacrylate in loose total hip prostheses.

We investigated the lymphocyte-mediated immune response to polymethylmethacrylate bone cement in 26 patients who had revision surgery for aseptic loosening of cemented total hip arthroplasties, at a mean time of seven years after the first replacement. We studied eight patients with cemented total hip arthroplasties which were not loose as controls. Patch tests to polymethylmethacrylate bone cement were positive in 13 patients with loosening, and these patients had higher lymphoblast transformation values against polymethylmethacrylate bone cement patients with a negative skin reaction (p < 0.01) or those in the control group (p < 0.001). Specific monoclonal antibodies were used to assess the percentage of certain cells of the immune system according to their cluster of differentiation (CD). There was a higher number of total T and B lymphocytes (CD2 and CD22) and interleukin-2 receptor-positive lymphocytes (activated cells, CD25) in patients with loose prostheses. More CD25 lymphocytes were found in patients with positive patch tests. The activation of the lymphocyte-mediated immune response was not related to the presence or absence of aggressive granulomatous lesions at the cement-bone interface.

Adolescent

Intraoperative radiotherapy in the multidisciplinary treatment of bone sarcomas in children and adolescents.

From September 1984 to December 1989, 38 patients of pediatric age with localized bone sarcomas received intraoperative radiotherapy (IORT) as part of a multidisciplinary treatment program. The age ranged from 6 to 21 years. The tumor histologies were 22 osteosarcomas and 16 Ewing's sarcomas. Thirty-four had initial primary disease (90%) and 4 were treated for local recurrence (10%). IORT was used on 32 untreated patients and in 6 previously treated with external beam radiotherapy (EBR). The IORT field included the surgically exposed tumor bed area. Single radiation doses ranging from 10 to 20 Gy were delivered, using 6-20 MeV electron beams. The median follow-up time for the entire group is 25 months (2-65+ months). The projected 5-year disease-free and overall survival rates are 65% and 69%, respectively. One patient developed a local recurrence in each histological group: one chondroblastic osteosarcoma and one cervical Ewing's sarcoma. Six patients died from metastatic progression: 3 initially recurrent tumors and three primary disease cases. Severe neuropathy and soft tissue necrosis were seen in some patients as IORT related complications. IORT is a feasible technique to be integrated in multidisciplinary programs that may promote local control in pediatric and adolescent patients with bone sarcomas. Peripheral nerves are dose-limiting tissue structures for IORT.

Adolescent

Posttraumatic ulnar neuropathy versus non-traumatic cubital tunnel syndrome: clinical features and response to surgery.

The outcome of 53 patients operated on either for posttraumatic ulnar neuropathy (PUN) or non-traumatic cubital tunnel syndrome (CTS) was reviewed after 3 years follow-up. Results were analyzed and compared considering the surgical technique used (neurolysis versus anterior transposition or combined) and a variety of clinical features that could influence outcome after nerve release. In the whole series, excellent outcome was obtained in 39 patients (73%). No major differences were found with the different surgical procedures. Slightly better results, but no statistically significant, were found in cases with CTS. As to clinical parameters, patients with CTS had a higher mean age, a shorter duration of symptoms and most were men. The presence of symptoms for more than one year before operation significantly diminished the chance of satisfactory recovery in cases with CTS, but not in those with PUN. For both CTS- and PUN-cases with symptoms for more than one year, neurolysis plus anterior transposition was the more useful technique. Our study shows that CTS and PUN differ to a certain extent in their clinical profile, electrophysiological findings and response to different surgical approaches and hence can be considered as two different clinical entities.

Adolescent

Leg lengthening by distraction through the callus of an arthrodesis.

Limb lengthening by means of distraction through the callus of a knee arthrodesis was performed in a 14-year-old boy with congenital hypoplasia of one lower limb. Knee arthrodesis was indicated because of destruction of the distal femoral epiphysis caused by a previous bone lengthening procedure.

Adolescent

Long term evaluation of high tibial valgus osteotomy.

We present a long term evaluation of 100 high valgus tibial osteotomies with a mean follow up of 11 years. Knees with slight or moderate osteoarthritis had the best results. Slight overcorrection was beneficial, but gross overcorrection was not. There were few complications and the overall long term results were good.

Activities of Daily Living

Secondary repair of ulnar nerve injury. 44 cases followed for 2 years.

A series of 44 patients with complete section of the ulnar nerve was reviewed on average 2 years after secondary repair. The procedures applied were fascicular grafting in 33 cases, epineural suture in 7, and suture in 4. Useful ulnar motor function was restored in 22 cases of fascicular grafting, in all 4 of fascicular suture and in 3 of epineural suture. Sensibility recovered in 23 patients operated on by fascicular grafts and in 10 of 11 treated by epineural or fascicular suture. Cases with unsatisfactory results had other associated severe lesions, i.e., median nerve section, vascular damage or tendon injuries. Early repair of clean-cut nerve sections by fascicular or epineural suture gives a good chance for recovery. Grafting should be performed within 3 months and no later than 1 year after the injury.

Adolescent