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M Manfrini

Publications and source records attributed to M Manfrini.

69 records · Page 4Linked to original sources
PubMedDate not supplied

A computer assisted approach for monitoring and planning biological reconstructions in orthopaedic oncology: preliminary results and future perspectives.

The evaluation of the mechanical strength of a reconstructed bone, and its evolution during the follow-up is, at present, almost impossible. This information, however, may prove extremely useful in clinical practice, both in the surgical planning and in the management of the rehabilitation therapy. In this work, a non-invasive technique, based on the use of finite element modelling, is presented that allows the simulation of the mechanical behaviour of a skeletal reconstructions starting from Computed Tomography data. This method was applied to study the evolution, during the first year of follow-up, of the strength of the reconstructed femur of a ten year-old child if a short, slow, level walk were allowed. The preliminary results indicate that the window sculpted by the surgeon to allow the anastomosis of the vascular pedicle acts as a stress concentrator and that the reduced bone mineral density, induced in the child's bone by the absence of load during the post-operative period, increases the stress level in the proximal femur.

Bone Neoplasms↗
PubMedDate not supplied

Tricalcium phosphate and hydroxyapatite ceramics in the surgery of bone tumors: preliminary results.

The authors report their preliminary experience in the use of substitutive bone compounds in order to fill the bone cavity after curettage. The material used is constituted by a biphasic compound, made up of tricalcium phosphate and hydroxyapatite. Twenty-one patients were submitted to surgery because of the presence of a benign or low-grade malignant tumor. After removing the neoplastic tissue the residual cavity was filled with: tricalcium phosphate/hydroxyapatite (5 cases); tricalcium phosphate/hydroxyapatite plus autogenous bone (8 cases); tricalcium phosphate/hydroxyapatite plus bone allografts (8 cases). A radiological evaluation obtained 12 months after treatment showed that the incorporation of the compound in granular form was nearly complete in most of the cases, while the blocks revealed partial remodelling which was more evident in the angles. Finally, bone resorption in the site of the compounds used was not observed.

Adolescent↗
PubMedDate not supplied

[Magnetic resonance for the study of osteosarcoma].

The authors report their experience with MR imaging in the study of osteosarcoma. Two main elements were evaluated: signal characteristics and loco-regional staging. Seventy-one patients were studied: 65 of them had central long-bone osteosarcoma, and 6 had telangiectatic long-bone osteosarcoma. T1- and T2-weighted spin-echo sequences were employed and all cases were scanned on 3 planes (sagittal, coronal, and axial). In 28 patients MR imaging was performed both before and after preoperative chemotherapy. The obtained data were compared to surgical and pathological findings. With the exception of the typical signal patterns of quite-osteoblastic osteosarcoma (which presents with low signal on both T1- and T2-weighted sequences), no particular signal features were observed which could help distinguish the different types of osteosarcoma. MR imaging is the method of choice in loco-regional staging for, in our series, it allowed a rational and adequate surgical planning. For this purpose, at least a longitudinal T1- and an axial T2-weighted images are required.

Adolescent↗
PubMedDate not supplied

Osteosarcoma associated with Paget's disease: a description of a rare case.

Osteosarcoma associated with Paget's disease is very malignant and has an extremely severe prognosis. This is also related to the usually advanced age of the patient and to the consequent impossibility of carrying out suitable chemotherapy. The case presented here is exceptional because of the young age of the patient, which allowed us to use a neoadjuvant chemotherapy protocol.

Adult↗
PubMedDate not supplied

Total body bone scan in the evaluation of tumor response to preoperative chemotherapy in the treatment of osteosarcoma.

With the introduction of preoperative (neoadjuvant) chemotherapy in the treatment of osteosarcoma, an early preoperative evaluation of the effectiveness of chemotherapy is essential, so that treatment may be modified in cases which are not responsive, and so that the surgical margin may be planned. The authors evaluate the accuracy of total body bone scan with Tc99m MDP in determining response to chemotherapy in 43 patients affected with osteosarcoma of the limbs, and preoperatively submitted to two cycles of chemotherapy with MTX i.v. and CDP i.a. All of the cases were submitted to a double bone scan examination, before and after preoperative chemotherapy. A bone scan evaluation using a qualitative method was compared to the percentage of necrosis observed in the tumorous tissue by histological examination carried out after surgery. In 58% of the cases the two values corresponded perfectly, in 28% of the cases bone scan evaluation overestimated response, and in 14% it underestimated it. In order to obtain quantitative preoperative data on response to chemotherapy in osteosarcoma, orientation towards the use of more sophisticated bone scan methods seems to be necessary, with computerized analysis of captation by dynamic measurement after infusion of Tc99m MDP or by radiocompounds with intracellular fixation such as Ga 67.

Adolescent↗
PubMedDate not supplied

Humeral lengthening in hypoplasia of the upper limb.

Surgical treatment for the correction of upper limb discrepancies with primary involvement of the humerus is reported. The operative technique, the lengthening procedure with the G3-IOR distractor, and the successive external fixation are described. In the seven extremities treated, the mean lengthening was 5.0 cm, the mean percentage lengthening was 25.2%, and the mean residual discrepancy was 2.9 cm. The authors believe that humeral lengthening is advisable for 13- to 15-year-old patients with hypoplasia of the humerus when the discrepancy is greater than 3 cm.

Adolescent↗
PubMedDate not supplied

Gastrocnemius flaps in the surgical treatment of sarcomas of the knee.

The authors discuss their experience with the pediculated gastrocnemius flap used in the oncological surgery of the knee, in 27 patients. Three groups of patients are evaluated: in one group the method was used in patients affected with bone sarcoma and associated with reconstruction of the resected bone segment; in another group the method was used after infection had occurred as a result of reconstructive surgery; in the third group the method was used at the same time as excision of sarcomas of the soft tissues. The gastrocnemius flap may be used to cover sufficiently wide areas of loss of skin and muscular substance around the knee, and may be effectively used to cover metallic prostheses or composite reconstructive implants (bone-cement-metal). We recommend using the covering technique at the same time as resection and reconstruction are performed in order to avoid the risk of infection, and thus reduce any changes in chemotherapy protocols that postoperative infection would require in these patients. The use of the gastrocnemius flap associated with excision of sarcomas of the soft tissues must be reserved for selected cases. The high incidence of local recurrence after such excisions indicates that either wider excisions using distant free flaps or the association of radiotherapy should be considered.

Adolescent↗
PubMedDate not supplied

The effect of intra-arterial versus intravenous cisplatinum in the neoadjuvant treatment of osteosarcoma of the limbs: the experience at the Rizzoli Institute.

The effect of intra-arterial versus intravenous infusion of cisplatinum on the histological response of osteosarcoma of the limbs was evaluated based on the results of three studies in which CDP was preoperatively associated with MTX and ADM (1st study), and with MTX, ADM, and IFO (2nd and 3rd studies). In the chemotherapeutic protocol that involved 3 drugs the percentage of "good histological responses to chemotherapy" (defined as tumor necrosis > 90%) was significantly higher in the 40 patients who were administered CDP by intra-arterial infusion as compared to that observed in the 39 patients treated with CDP by intravenous route (78% versus 46%: P .004). In the two sequential studies where 4 drugs were used, the percentage of good histological responses was essentially the same for patients treated with CDP administered intravenously, and for those treated with CDP administered intra-arterially (78% versus 84%). Regardless of the route of infusion used to administer cisplatinum the percentage of "good" histological responses was significantly higher in the 109 patients treated with the 4-drug protocol as compared to the 79 patients treated with the 3-drug protocol (82% vs 62%; P .04). This difference may essentially be attributed to the higher percentage of good responses observed in the 4-drug protocol in patients treated with CDP administered intravenously (78% vs 46% for patients treated i.v. with the 3-drug protocol; P .006). For the patients instead treated with CDP administered intra-arterially the percentage of good responses was essentially the same with the 4-drug protocol and with the 3-drug protocol (84% vs 78%; P ns). These data lead us to conclude that in the neoadjuvant treatment of osteosarcoma of the limbs a preoperative 4-drug protocol (MTX, CDP, ADM, IFO) is more effective than a 3-drug protocol (MTX, CDP, ADM), and that in a 4-drug preoperative chemotherapy protocol intra-arterial infusion of CDP does not offer particular advantages as compared to intravenous infusion.

Adolescent↗
PubMedDate not supplied

[Local recurrence after surgical or surgical-chemotherapeutic treatment of osteosarcoma of the limbs. Incidence, risk factors and prognosis].

METHODS: Local recidivation (incidence, risk factors an prognosis) was analysed retrospectively in 765 patients with non-metastatic osteosarcoma of the extremities treated between 1972 and 1992 either with surgery alone (78 cases) or with surgery and associated adjuvant (258 cases) and neoadjuvant chemotherapy (429 cases). RESULTS: The local recurrence of the disease, which was documented in 26 patients (3.4%), was significantly related to the type of surgery performed (1.1% in 344 amputated patients vs 5.2% in 422 patients treated with resection; p < 0.003) and with surgical margins (0.6% in 700 radical or extensive operations vs 22.7% in 66 marginal or intralesional interventions; p = 0.0001). In patients treated with neoadjuvant chemotherapy, the incidence of local recidivation was also correlated with the type of histological response to chemotherapy (2.9% in 274 cases with a "good" response vs 8.4% in 154 cases with a "poor" response; p < 0.021). In all 26 patients local recidivation was associated with metastases occurring before (16 cases), after (3 cases) or in concomitance (7 cases) with the local recurrence of neoplasia. In spite of treatment performed at the start of recidivation, 25 patients (96.1%) died from the tumour whereas the mortality rate in those patients with metastases but no local recidivation was only 72.1% (261 out of 362 cases). This difference was also statistically significant (p < 0.01). CONCLUSIONS: The results obtained appear to justify the current trend of minimising demolitive surgery in osteosarcoma of the extremities. Surgery should only be performed in these patients by centres able to make an adequate evaluation of surgical margins and the histological response to preoperative chemotherapy. In view of the fatal prognosis linked to recidivation and the high probability of its onset in cases with inadequate surgical margins and a poor response to chemotherapy, the authors propose that subsequent amputation should be performed immediately in those patients undergoing resection who present both these conditions.

Bone Neoplasms↗