Search PubMed⌕ Search

Biomedical subjects

C Burri

Publications and source records attributed to C Burri.

At least 55 records · Page 3Linked to original sources
PubMed1986

Experimental studies on the influence of fibrin adhesive, factor XIII, and calcitonin on the incorporation and remodeling of autologous bone grafts.

In an experimental study on sheep the effects of fibrin adhesive system (FAS), plasma factor XIII (FXIII), and calcitonin on autologous cancellous bone grafts were studied. Drill holes in the tibia were filled with transplant bone, either untreated or locally treated with fibrin adhesive, with or without plasma factor XIII. We used 24 sheep, divided into three groups. Plasma factor XIII and calcitonin were administered parenterally; the third group received no treatment. For evaluation we carried out quantitative bone and fluorescence morphometry and microangiography. We found that local fibrin adhesive significantly decreased the remodeling and growth of the transplanted cancellous bone. Plasma factor XIII, given parenterally, increased the amount of bone in the transplant site; calcitonin showed no visible effect.

Animals↗
PubMed1986

The stabilizing effect of various implants on the torn acromioclavicular joint. A biomechanical study.

A biomechanical in vitro test was performed to determine the stabilizing effect of various implants for the surgical treatment of the torn acromioclavicular joint. In a specially designed testing device, plastic and cadaver specimens of the shoulder girdle were stressed in various ways. Different dislocations between the acromion and the clavicle and between the clavicle and the coracoid were determined, as well as the stiffness of the implants. A convenient stabilizing effect combined with less rigid fixation to secure the newly treated AC joint was provided by K-wire fixation with cerclage. Interfering shear and bending stresses could be avoided with this method, while the other implants showed various disadvantages. From a biomechanical point of view, a carbon-fiber ligament replacement provides sufficient stability in cases of chronic acromioclavicular separation.

Acromioclavicular Joint↗
PubMed1986

Intraoperative transesophageal two-dimensional echocardiography in total hip replacement.

A number of studies in medical literature suggest that during implantation of hip prostheses pulmonary embolism of medullary contents and of air may occur. Proof of this suggestion was based on histological examination of lung tissue in animal experiments as well as on post mortem examinations of human tissue. In vivo evidence of this suspected embolism has been lacking so far, since an appropriate technique has not been available. Using transesophageal two-dimensional echocardiography, continuous imaging of the right atrium and the right ventricle can be performed in order to prove this suspected embolization in vivo. Thus, in a prospective randomized study of 26 patients undergoing hip surgery, the right atrium and right ventricle were continuously imaged. Simultaneously, the end-expiratory CO2 partial pressure was recorded. The medical literature suggests that a venting hole in the shaft of the femur prevents the rise in pressure in the medullary space and thus also averts embolism. Therefore, prior to the implantation of the shaft prosthesis, and in order to vent the medullary space, in 13 patients a 4.5-mm lateral borehole was drilled into the femoral shaft, located two finger breadths distal to the point were the end of the prosthesis would be positioned. In 12 of 13 patients in the control group without boreholes, transesophageal two-dimensional echocardiography revealed that air bubbles formed during the implantation of the shaft. In the group with boreholes, however, presence of air could be demonstrated in only four patients (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Marrow↗
PubMed1986

Continuous passive motion after knee-joint arthrolysis under catheter peridural anesthesia.

The results of arthrolysis of a stiff knee are often poor because postoperative pain prevents the early active mobilization that is so essential. Adequate analgesia may be ensured by the use of continuous anesthesia via a peridural catheter; in combination with continuous passive motion, such analgesia is able to maintain, and often improve, the range of movement obtained at surgery. Twenty-two patients treated in this way showed improvement in the range of movement between 39 degrees and 120 degrees. Patients with post-traumatic knee stiffness achieved an average improvement in the range of movement of 93%, while those with stiffness following infection improved by only 55% on the average. The preoperative loss of movement does not appear to determine the end result; the etiology of the stiffness is more important.

Adolescent↗
PubMed1986

[Simultaneous autologous spongioplasty and muscle flap transposition to restore the continuity of the leg with an osteitis defect].

About 12% of compound fractures of the lower leg give rise to posttraumatic osteitis. Loss of bone by sequestration causes many problems particularly if soft tissue quality is poor. Cancellous and corticocancellous bone from the iliac crest is used for bony reconstruction. To obtain bony union, a well vascularised recipient for the graft is essential. Local muscle flaps and distant microvascular flaps and distant microvascular flaps improve vascularity by their separate connection to the vascular system. We treated 54 soft tissue defects by local muscle flaps in 41 and by microvascular flaps in 13 cases. In 21 cases a cancellous or a corticocancellous bone graft was used. Necrosis or partial necrosis of the flap occurred in 12 cases. Skin closure and healing was obtained by secondary procedures. Combined muscle flap and bone grafting was found to allow full weight bearing within reasonable period of time.

Bone Transplantation↗
PubMed1986

[Indications for immediate and delayed amputation in severe soft tissue and skeletal injuries of the distal tibia].

Primary amputation of the lower extremity has become rare in the last years due to the advances in rigid fixation of the bone, plastic and microsurgical techniques and aseptic surgery. Primary amputation is indicated in the presence of non-reconstructable lesions of vessels and/or nerves, secondary amputations when vascular, neural or septic complications occur.

Amputation, Surgical↗
PubMed1986

[Resorbable implants for refixation of osteochondral fragments in joint surfaces].

Resorbable pins made of solid polydioxanone (PDS) were tested for refixation of osteochondral fragments. In both medial femoral condyles of sheep osteochondral fragments were chiselled and refixed by 3 PDS pins. After 3 months the sheep were sacrificed and healing of the fragments investigated histologically and biomechanically. Fragment dislocation was not seen in any of the cases and the cartilage surface could be described as normal. The strength of the bone healing zone reached 80% of the strength of the normal bone. The contact surface between fragment and subchondral bone showed complete bony healing. Only the border of the cartilage flake was still visible. The PDS pins had not been completely biodegraded after 3 months.

Animals↗
PubMed1986

[Transplantation of bones in traumatic and posttraumatic septic conditions].

The treatment of acute and chronic osteitis should be standardized, using the following steps: débridement/sequestrectomy; stabilization; eradication of local infection; revascularization; filling-up defects--bone transplantation. The transplantation of bone is only successful if the defect area is prepared following steps 1-4 mentioned above. If possible, only autologous bone should be transplanted into an infected bone area. For the take of the transplanted bone, good vascularization of the infected area is of great importance. To obtain the best function possible, the Kinesitherapy should be carefully supervised by the surgeon.

Bone Transplantation↗
PubMed1985

[Therapeutic principles, organizational and technical implementation].

A minimum of organised measures is mandatory in every clinic, where posttraumatic or postoperative bone infection may occur. Technical principles in the treatment of osteomyelitis are: debridement, stability, local anti-infection procedures such as irrigation drainage, PMMA-chains or Taurolin gel, filling of the osseous defect and adequate vascularity (muscle flap, muscle transplant with microvascular anastomosis).

Asepsis↗
PubMed1985

[Cruciate ligament replacement--current status. Carbon fiber implants].

The substitution of cruciate ligaments with carbon fibre implants is a treatment method for chronic ligament instabilities which is sufficiently reliable and can be easily standardized. The good bio-compatibility of the material is sufficiently demonstrated, its biomechanical properties - above all the tensile strength - are excellent. The poor resistance to shearing forces of the carbon fibre implants has to be considered as a limiting factor. The risk of a rupture of the implant can be considerably reduced by coating the prospective intra-articular ligament section and by smoothing off the borehole edges. A check-up investigation of 96 out of 112 operated patients showed good or satisfactory results in 3/4 of the examined patients.

Adolescent↗
PubMed1985

Bone healing stimulated by plasma factor XIII. Osteotomy experiments in sheep.

Sheep had their right metatarsals osteotomized midshaft and stabilized by plate and screws. One group was injected with 1250 units of Factor Thirteen for 9 days postoperatively, and a control group received placebo injections. After 8 weeks, the bones were evaluated biomechanically, histomorphologically and by densitometry. The bones of the treated group had a significantly higher tensile strength than the bones of the control animals. The correlation of biomechanical and morphological results demonstrated that the tensile strength increased with an increasing number of osteons crossing the osteotomy gap. The hydroxyapatite content of the bone healing zone was 7.3 per cent higher for the treated bones than for the control bones.

Animals↗
PubMed1985

[Postoperative knee joint mobilization in catheter peridural anesthesia following arthrolyses of the knee joint].

The results of arthrolysis of a stiff knee are often poor due to post-operative pain preventing early active mobilization that is so essential. Adequate analgesia may be ensured by the use of continuous anaesthesia via an epidural catheter, and in combination with continuous passive motion such analgesia is able to maintain, and often improve, the range of movement obtained at surgery. 22 patients treated in this way showed an improvement in the range of movement of between 39 and 120 degrees. Patients with post-traumatic knee stiffness achieved an average improvement in the range of movement of 93%, while those with stiffness following infection only improved by 55% on the average. The pre-operative loss of movement does not appear to determine the end result: the aetiology of the stiffness is more important.

Adolescent↗
PubMed1985

Carbon fiber replacement of the ligaments of the shoulder girdle and the treatment of lateral instability of the ankle joint.

A normal active human being will not accept chronic instability or persistent luxation of any joint. Many attempts have been made to stabilize a damaged joint with autogeneic and allogeneic materials and by various surgical techniques. In animal and clinical trials, carbon fibers are reported to be a promising material for ligament replacement in chronic joint instability. The authors are investigating carbon fibers not only for repair of chronic instability of knee joints but also for chronic luxations and subluxations of the sternoclavicular, acromioclavicular, and ankle joints. For long-term stability of the new ligament, carbon fibers must be implanted in cancellous bone channels. Ingrowth of connective tissue and newly formed bone produces a secure ligament anchorage. A temporary tension band wire loop immobilizes the sternoclavicular or acromioclavicular joint. The ankle ligament replacements are immobilized with a weight-bearing plaster boot for six weeks postoperation. The use of carbon fibers as a ligament replacement in the sternoclavicular, acromioclavicular, and ankle joints produces favorable functions and stability. Reconstruction of the normal ligament insertions of a joint is essential, particularly with respect to supination and free range of movement. Of 56 cases with lateral chronic instability of the ankle, 51 with a mean average postoperative follow-up period of two years, 49 had subjectively good results. Stable joints were demonstrable in 48 cases; supination was limited in four cases.

Acromioclavicular Joint↗
PubMed1985

Carbon fiber ligament replacement in chronic knee instability.

Procedures currently acknowledged or still accepted and performed in the operative treatment of chronic instability of the knee include autogeneic, allogeneic, and xenogeneic grafts or alloplastic materials such as carbon fibers. After years of experimental studies of the carbon material itself and its behavior in animals, the following facts have been established. Carbon fibers possess a good biocompatibility, have favorable elasticity (by use of a band with a braid angle of 43 degrees), and permit the ingrowth of collagenous fibers between the carbon fibers of the prosthesis. With carbon fibers, an anatomic reconstruction of the injured ligament is possible. These fibers must be incorporated in bone to provide a long-lasting anchorage. For fixation, the band is pulled through bone channels or put under a trap door at the site of the original ligament insertion. Since ruptures have occurred when pure carbon strands were used intra-articularly, a coat of resorbable collagen has been applied. In addition, the intra-articular segment of the band is enveloped in a sheet of dura or fascia lata, thus providing stability against shear stresses. Of 64 patients followed up over 13.6 months on average, 60 were satisfied: 28 had stable knees; 30 had minor instability; and six were unstable. The range of movement was equal to the unaffected side in 37, slightly decreased in 23, and much reduced in four cases.

Carbon↗