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Biomedical subjects

C H Barbieri

Publications and source records attributed to C H Barbieri.

15 recordsLinked to original sources
PubMed2004

The end-to-side peripheral nerve repair. Functional and morphometric study using the peroneal nerve of rats.

Morphologic and functional recovery following an end-to-side repair was studied comparatively with conventional end-to-end repair in a model of peroneal nerve lesion in rats. Twenty-eight rats were used and divided into four groups according to the reparative procedure following nerve division: (1) nerve stumps buried into neighboring muscles (n = 8); (2) conventional end-to-end repair (n = 7); (3) end-to-side repair onto the tibial nerve (n = 8); (4) sham operation (n = 5). The sciatic functional index (SFI) was evaluated at weekly intervals for 8 weeks, the peroneal nerve being resected on the 56th day for histologic and morphometric studies. The SFI progressively improved in Groups 2 (-16.9) and 3 (-22.7), although it did not reach normal values (around -8). The average nerve fiber density increased to normal values in both Groups 2 and 3, although accompanied by a marked decrease of average minimal and maximal nerve fiber diameter, myelin sheath area and G quotient. The differences between Groups 2 and 3 or Groups 2 and 4 were not significant. We conclude that, although resulting in significant morphologic and functional recovery, end-to-side repair is not as efficient as the conventional end-to-end nerve repair. However, end-to-side repair has a potential for application in selected cases in humans.

Animals↗
PubMed2004

The use of a muscle graft to repair a segmentary nerve defect. An experimental study using the sciatic nerve of rats as model.

The use of a devitalized skeletal muscle graft and conventional nerve graft to repair a 5mm long segmentary sciatic nerve lesion was studied in rats by means of functional, morphometric and spinal cord motor neuron cell response evaluation. Thirty-four rats were used and divided into four groups according to the procedure: (1) sham operation; (2) conventional nerve grafting; (3) muscle grafting; (4) unrepaired lesion. The sciatic functional index (SFI) was evaluated every fortnight up to the 105th postoperative day by measuring three parameters in the rats' footprint. The animals of Groups 2 and 3 presented initial complete functional loss, followed by slow but steady recovery, with final similar SFIs. The histologic and morphometric studies showed an increased small diameter/thin myelin sheath nerve fiber density distally to the lesion site for both types of graft. An increased population of motor neurons was observed in the anterior horn of the lumbar spinal cord segment with both types of grafts, but not in the control groups. The SFI, histologic and morphometric data did not differ significantly between the two types of graft, thus indicating a similar behavior. The authors conclude that a 5mm long skeletal muscle graft works as well as a conventional nerve graft.

Animals↗
PubMed2001

Aneurysmal bone cyst with chromosomal changes involving 7q and 16p.

An aneurysmal bone cyst was submitted to cytogenetic analysis. The modal chromosome number was 46. The composite karyotype was 40 approximately 48,XY,-Y[4],-6[3],del(7)(q32)[3],-9[3],+12[2],+13[2], inv(16)(p13.1q24)[4],-17[3],-19[4],-20[3][cp13]. The clonal structural changes detected were del(7)(q32) and inv(16)(p13.1q24). The breakpoints involved affected areas to which important genes for cell cycle regulation have been mapped. There is only one report in the literature of three aneurysmal bone cysts presenting clonal karyotypic alterations. The cytogenetic study of the aneurysmal bone cyst reported here showed different results when compared to those previously described in the literature.

Adolescent↗
PubMed2001

Correlation between functional index and morphometry to evaluate recovery of the rat sciatic nerve following crush injury: experimental study.

An experimental study on the correlation between functional and morphologic recovery of crushed sciatic nerves was carried out in rats. The sciatic nerve of 33 rats, divided into three groups, was submitted to controlled crushing injury on a 5-mm long segment, in a universal testing machine for 10 min with three different loads (100, 500, and 15,000 g, respectively). Functional recovery was evaluated, using a modified sciatic functional index (SFI) at weekly intervals up to the 60th postoperative day, at which time, the animals were sacrificed for histologic and morphometric studies of the nerves. Results were compared with those of normal untouched nerves and nerves submitted to segmentary resection without repair. Initial loss of function was observed in all animals with crush injury, but recovery to a nearly normal SFI occurred after progressively longer intervals (25, 39, and 53 days), as a function of load. Nerve-fiber density was increased in the groups submitted to lower loads, but statistically significantly decreased in the animals submitted to the 15,000-g crush. The authors conclude that the SFI is directly correlated with nerve-fiber density and, therefore, is an adequate tool for evaluating sciatic functional deficiency in the rat.

Animals↗
PubMed2000

Scintigraphic evaluation of tibial shaft fracture healing.

A scintigraphic study of the healing process of type A and B closed tibial shaft fractures was carried out in 40 cases treated non-operatively, comprising 32 men and eight women aged 30.6 yr on average. Scintigraphic scans were obtained with technetium methylenediphosphonate (MDP-Tc99m, 25 mCi) at 6, 12 and 24 weeks after the fracture and an activity index was calculated taking the mean of three consecutive uptake counts for both fractured and normal opposite leg, used for comparison. The results showed that the activity index in general decreased progressively from the first to the third evaluation, with little difference in behaviour between the two types of fractures. However, for B type fractures the activity index remained stable from the first to the second evaluation, followed by a marked decrease at the third evaluation, with a comparable end result for both fracture types. It was concluded that a decrease of the activity index occurs in both types of closed fractures undergoing uneventful healing and that such a decrease can be taken as a parameter for further studies which include delayed union and non-union.

Adult↗
PubMed1999

Use of a delayed cortical bone graft to treat diaphyseal defects in the forearm.

The technique of delayed autogenous cortical bone grafting was used in 17 patients (6 women, 11 men, with an average age of 22 years) to treat diaphyseal defects resulting mainly from closed or compound fractures complicated by infection and bone tissue loss. Bones affected were the humerus in 1 case, the radius in 7 cases, the ulna in 4 cases, the radius and ulna in 2 cases, the first metacarpal in 1 case, and the femur in 2 cases. The average length of the defect was 5.7 cm and the graft, prepared from the anteromedial aspec of the tibia, was at least 1.5 cm longer than the defect. The graft application was combined with rigid internal fixation using an AO 3.5 mm DCP plate in most cases and this permitted early active movement. Union occurred without the need for any additional grafting procedure in 14 patients and within an average of 23 weeks. In most cases there was an increase in the thickness of the graft probably as a result of osteo-induction, with consequent restoration of the original diameter of the recipient bone diaphysis. The most frequent complication was infection (4 cases), and this was controlled by means of debridement, cleaning and antibiotics. A delayed graft provides mechanical support, incorporates quickly and is therefore a reasonable alternative method for treating diaphyseal defects of long bones, particularly in the upper limb.

Adolescent↗
PubMed1998

Mechanical strengths of tendon sutures. An in vitro comparative study of six techniques.

A comparative study of six tendon suturing techniques (1. Modified Kessler + simple epitendinous running suture; 2. Modified Kessler + Halsted epitendinous suture; 3. "Six strand" suture; 4. "Interlocking" suture; 5. "Cross stitch" suture; 6. simple epitendinous running suture) was carried out by evaluating strength in relation to the beginning of separation between the tendon stumps, a 3 mm separation and rupture in porcine flexor tendons. The technique most resistant to initial separation was the modified Kessler + Halsted epitendinous suture followed by the "Six strand" suture. The "Six strand" suture was the most resistant to the 3 mm separation and rupture followed by the modified Kessler + Halsted epitendinous suture. Despite the greater resistance to rupture of the "Six strand" technique, we conclude that modified Kessler + Halsted epitendinous suture showed the best overall performance and was easier to use.

Animals↗
PubMed1997

Use of a bone block graft from the iliac crest with rigid fixation to correct diaphyseal defects of the radius and ulna.

We report our experience with the use of a bone block graft from the iliac crest to correct diaphyseal defects of the forearm bones. The technique was used in 12 patients (ten men and two women, average age 29 years) for defects resulting mainly from either closed or compound fractures, which later developed infection and bone tissue loss. The average dimensions of the graft required to correct the defect was 3.5 x 1.8 cm. The graft application was combined with rigid fixation with an AO 3.5 mm DCP plate, permitting early active motion. The graft incorporated without any additional grafting procedure in ten cases within 17.2 weeks on average. The most frequent complication was infection (four cases), controlled by means of debridement, cleansing and antibiotics. A comparative analysis of the immediate and final radiographs of the graft showed an average 30% loss of bone mass despite integration. We conclude that the technique of bone block grafting to correct diaphyseal defects of the radius or ulna is relatively easy to carry out and has a high success rate.

Adolescent↗
PubMed1996

Triradiate skin incision for dorsal approach to the wrist.

A new triaradiate skin incision is presented as an approach to the wrist. Centred over Lister's tubercle, it consists of one longitudinal proximal and two oblique distal rays, making three 120 degrees skin flaps. These provide an excellent triangular operating field to the distal radius, the radiocarpal joint and the carpus itself, allowing for most procedures in this region. There have been no complications in 32 patients, and the cosmetic appearance has been excellent in most of them.

Adult↗
PubMed1996

The posterior interosseous forearm island flap for skin defects in the hand and elbow. A prospective study of 51 cases.

The authors' experience of 51 posterior interosseous forearm island flaps is presented. Its main indications were inadequate scar or scar contraction and complex trauma with gross skin loss, either acute or postprimary. The flap healed uneventfully in 45 cases (88%), but in six it was partially or subtotally lost due to necrosis. Late complications included hair growth in the first web and palm, flap redundancy and hypertrophic scar at the donor site. The posterior interosseous island flap produces excellent skin coverage but is difficult to raise and tends to develop oedema and occasionally necrosis.

Adolescent↗
PubMed1993

The effect of venous occlusion on the integration of vascularized cortical bone graft.

The biologic phenomena involved in the healing process of vascularized, cortical bone grafts, vascularized grafts with venous occlusion, and conventional cortical bone grafts, were studied in rabbits. The middle third of the radial diaphysis was the donor site, with a 1.6-cm-long bone cylinder delimited by double transverse osteotomies. The vascularized grafts were raised by extraperiosteal dissection, with preservation of their vascular pedicle, while the conventional grafts were obtained by subperiosteal dissection. The vascularized graft with venous occlusion had its draining vein ligated. Radiologic, scintigraphic, and histologic studies were undertaken at days 7, 15, 30, and 60 postoperatively. Results demonstrated that the vascularized graft healed earlier than the corresponding vascularized graft with venous occlusion and than the conventional graft, respectively. The vascularized graft with venous occlusion suffered some degree of impairment of its irrigation, probably due to retrograde block of the arterial blood flow. It underwent a degree of bone necrosis, followed by resorption and creeping substitution, which delayed its integration. This seemed to be a temporary effect, for it healed earlier than the conventional graft.

Anastomosis, Surgical↗
PubMed1991

The fate of tendon grafts used to reconstruct the digital annular pulleys.

An experimental morphological study on the reconstruction of the digital annular pulleys has been carried out in dogs. The segment corresponding to zones 1 and 2 of the flexor apparatus of the 2nd and 5th digits of the left forepaw was chosen for the experiment. The whole flexor apparatus was resected and a single digital pulley (A 2) was reconstructed, using segments of the animals own deep flexor tendon. A length of silicone rubber tube was used as tendon spacer. The new pulleys showed marked degeneration of the collagen fibres and thinning which increased with time and may be the cause of decrease in strength. A layer of mesothelial cells with secretory properties developed at the interface between the tendon graft and the spacer.

Animals↗
PubMed1986

Studies on tendon healing. A comparison between suturing techniques.

An experimental study comparing Kessler's and Tsuge's techniques for tendon suture was undertaken in dogs. Both second and fifth flexor digitorum profundi tendons of the left forepaw were divided in the segment corresponding to zone 2 of human hands. Following division, the tendons to the second digit were repaired by Kessler's technique and those to the fifth digit by Tsuge's method. Results were evaluated by means of standard and polarized--light microscopy, intravascular dye injections and tensile strength tests. Both ordinary and polarized--light microscopy showed that a microscopical gap develops between the tendon ends, being filled in with healing tissue which undergoes progressive maturation. The tensile strength tests showed that the deformation (elongation) progress directly with load, up to the point of rupture; the suture thread does not interfere with this. Furthermore, strength increases with time. Intravascular dye injection showed that a net of newly formed blood vessels develops at the site of section and suture, previously destitute of macroscopical vessels. The new vessels tended to redistribute them selves to resemble the pattern in normally vascularized regions. It was not possible to detect, by means of the methods employed, any important difference between Kessler's and Tsuge's techniques for tendon suture.

Animals↗