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Ed H M Hartman

Publications and source records attributed to Ed H M Hartman.

12 recordsLinked to original sources
PubMed2006

The use of the pedicled supraclavicular flap in noma reconstructive surgery.

Three noma patients with large unilateral facial defects were reconstructed using the pedicled supraclavicular flap technique in the Noma Children Hospital in Sokoto, Nigeria. The results are-although not completely perfect-encouraging enough to report and to repeat the technique in future reconstructive noma surgery after moderate modifications. It is advised not to tunnel the pedicle in the neck, but instead to open the neck. Then, the flap can be inset in a Z-plasty fashion to close the neck without the chance of compression of the pedicle of the flap. In this way flap necrosis can be prevented, without the risk of a scar contracture of the neck. Another technique, which can prevent partial flap necrosis and loss of tissue, with the need for secondary stage interventions, is a delay procedure of the flap. Incorporation of the fascia in the pedicled supraclavicular flap can be another option to fulfil the abovementioned requirements.

Adolescent↗
PubMed2006

Octyl-2-cyanoacrylate tissue glue (Dermabond) versus Monocryl 6 x 0 Sutures in lip closure.

OBJECTIVE: To assess the value of octyl-2-cyanoacrylate tissue glue in lip closure versus Monocryl stitches. DESIGN: Closure of a cleft lip can be done using transcutaneous Monocryl 6 x 0 sutures or using octyl-2-cyanoacrylate tissue glue (Dermabond). In 15 consecutive patients, the cleft lip was closed with Monocryl 6 x 0 and in another 15 consecutive patients, Dermabond was applied. Outcome parameters were complications, satisfaction of the parents with the cosmetic result, and the cosmetic result as judged by professionals. Satisfaction of the parents was assessed using a questionnaire and a visual analog scale. The cosmetic result as judged by professionals was measured by rating standardized pictures according to a visual analog scale. SETTING: A tertiary referral center for children with craniofacial anomalies. RESULTS: Complications were equal in both patient groups (p = .273). Satisfaction of the parents, as well as the professionals, with the cosmetic result did not show significant differences between the Monocryl 6 x 0 and the Dermabond groups (p = .922 and .983, respectively). However, parents were significantly more positive about the cosmetic result than the professionals were (p = .000). CONCLUSION: The results of lip closure using Dermabond tissue glue equal the cosmetic results of lip closure using transcutaneous Monocryl 6 x 0 sutures.

Cleft Lip↗
PubMed2005

DBM induced ectopic bone formation in the rat: the importance of surface area.

Demineralized bone matrix (DBM) has been shown to induce ectopic endochondral bone formation, when intramuscularly implanted in rats. In earlier studies we have found a variation in bone formation capacity of this DBM. This might be due to the properties of the DBM itself, but the use of DBM blocks could be of influence as well. Therefore, this study was designed to investigate whether increasing the surface area of the DBM by morsellizing, influences the bone formation capacity. In view of this, DBM implants and morsellized DBM (MDBM) implants were placed intramuscularly in a rat model. At six weeks the implants were retrieved and evaluated by histology and histomorphometry. The results demonstrated that significant amounts of newly formed bone were present in some DBM as well as some MDBM implants while in others no, or very little new bone was found. Histomorphometric analysis showed an average bone formation of 2.6% in DBM implants and an average of 1.9% in MDBM implants. Still, the amount of bone formation was limited compared with previous studies. It is concluded that enlargement of the surface area by morsellizing DBM implants is not an important factor in bone forming capacity.

Animals↗
PubMed2005

Ectopic bone formation in rats: the importance of the carrier.

Much research has been done to develop the ideal bone graft substitute (BGS). One approach to develop this ideal BGS is the use of growth factors, but for this approach osteoprogenitor cells are needed at the site of reconstruction. An alternative is a cell-based approach, where enough cells are provided to form bone in a carrier material. In previous studies of our group, titanium (Ti) carriers have been used, because of the excellent mechanical properties and the bone-compatibility of this material. On the other hand, calcium phosphate (CaP) ceramics are known for their excellent osteoconductivity. The aim of this study is to investigate the influence of the carrier in a cell-based bone regeneration approach, whereby we hypothesize that CaP-ceramic implants will induce more bone formation than Ti-fiber implants, in the same animal model as our previous experiment. Ti-fiber mesh implants and ceramic implants were seeded with rat bone marrow cells (RBM) and implanted subcutaneously. Histological analysis after one, three and six weeks showed differences in the way of bone formation in the two groups: bone appeared to grow from the center to the periphery of the implant in the titanium group, while bone formation in the ceramic group occurred through the whole implant. Histomorphometrical analysis after one week showed very limited bone formation for both the titanium and ceramic group. At three weeks, the amount of bone formation was increased till about 10% for the titanium group and 18% for the ceramic group. No significant difference between the two groups could be observed. In the six week group, the bone formation was 6% (Ti) and 23% (CaP), respectively (P < 0.001). Further, bone formation started earlier in the CaP-ceramic scaffolds than in the Ti scaffolds. Our hypothesis could be confirmed: ceramic implants induce more bone formation than titanium implants.

Animals↗
PubMed2004

Ectopic bone formation in rats: the importance of vascularity of the acceptor site.

Bone graft substitutes (BGS) can be fabricated by the combination of three key ingredients: (1) competent bone-forming cells, (2) a suitable framework or scaffold, and (3) the presence of biological stimulants. Although much research has been done to develop the ideal BGS, still the results are not very consistent. In view of this, the cellularity and vascularity of the recipient site are supposed to be important for the osteoinductive capacity of BGS. Therefore, we hypothesized that a muscle recipient site could favor bone formation in a cell-based BGS compared to a subcutaneous recipient site due to the higher vascularity of muscle tissue. To prove this hypothesis, 48 titanium fiber mesh implants were seeded with rat bone marrow stromal cells (RBM) and implanted subcutaneously and intramuscularly in the adductor thigh muscle of rats. The amount of bone formation after 1, 3 and 6 weeks was evaluated by histology and histomorphometry as well as by calcium content. Analysis revealed that the bone formation increased during implantation. However, bone formation did not exceed 12% of the implant surface, both for the intramuscular and subcutaneous recipient site. Also, no significant differences in bone amount between these two sites existed. Consequently, our hypothesis could not be confirmed.

Absorbable Implants↗
PubMed2003

Contralateral reinnervation of midline muscles in nonidiopathic facial palsy.

The purpose of this study was to analyze contralateral reinnervation of the facial nerve in eight patients with complete facial palsy after surgery or trauma and seven healthy volunteers. All patients had contralateral reinnervation of facial muscles as demonstrated by electrical nerve stimulation versus none of the control subjects. Four patients had facial muscle movements at the site of the damaged nerve. In one patient this was entirely the result of contralateral reinnervation, whereas the other three patients had innervation both ipsilaterally and contralaterally. This implies that renewed facial muscle activity should be examined considering the origin of the reinnervation, either contralateral or ipsilateral. Contralateral reinnervation is a common phenomenon after total facial palsy and can occur alongside ipsilateral reinnervation. It can be mistaken for adequate reinnervation of the damaged nerve, causing postponement of dynamic reconstruction therapy.

Action Potentials↗
PubMed2003

Donor-site morbidity after free vascularized autogenous fibular transfer: subjective and quantitative analyses.

The purpose of this study was to determine the subjective and quantitative donor-site morbidity after removal of a free vascularized fibula flap for autoreconstruction. Ten patients and six age-matched, healthy control subjects were included in this study. The postoperative periods ranged from 6 to 87 months. Subjective donor-site morbidity was assessed with a patient questionnaire and the Enneking system. For quantification of donor-site morbidity, gait was evaluated during normal walking, walking under visual and cognitive constraints, and walking at a velocity higher than the preferred one. In general, the patient perception of donor-site morbidity was low. Complaints were frequently mentioned, however, including pain (60 percent), dysesthesia (50 percent), a feeling of ankle instability (30 percent), and inability to run (20 percent). Gait analyses revealed that patients walked at a lower preferred velocity, compared with control subjects. Furthermore, they demonstrated significant increases in the coefficients of variation of stride time during walking under visual and cognitive loads and during walking at a velocity higher than the preferred one, compared with normal walking. These increases were not observed for control subjects. These findings suggest that the reautomatization of gait is affected among patients. This study demonstrates that fibula harvesting is associated with low subjective morbidity but frequent complaints. Walking during complex tasks and at high velocities reveals that restoration of gait is not complete after partial fibulectomy.

Adult↗
PubMed2002

In vivo magnetic resonance imaging explorative study of ectopic bone formation in the rat.

In animal studies of tissue engineering of bone, histology remains the standard for assessing bone formation. As longitudinal studies with this method are feasible only at the cost of large numbers of animals, we looked for an alternative. Therefore, demineralized bone matrix (DBM) and inactivated demineralized bone matrix (iDBM) implants were subcutaneously implanted in a rat. At 1, 3, 5, and 7 weeks postimplantation soft X-ray and magnetic resonance imaging (MRI) were done to monitor bone formation in the implants. At 7 weeks, the animal was killed and the implants were retrieved for histology. Our results showed that in vivo MRI is well suited to assess bone formation larger than 0.5 mm in diameter and to monitor the complete three-dimensional shape of the newly formed bone noninvasively and longitudinally. The MRI results matched well with the histology results obtained at 7 weeks. In contrast, X-ray imaging appeared inappropriate to monitor the bone formation process in DBM.

Animals↗
PubMedDate not supplied

Donor-site complications in vascularized bone flap surgery.

Microvascular osteocutaneous free flaps have given reconstructive surgeons a powerful tool in the reconstruction of composite defects in head and neck surgery. Radial forearm, scapula, iliac crest, and fibula flaps have been used extensively in mandibular reconstruction. The inevitable donor-site morbidity of these osteocutaneous flaps has received less attention than the reconstructive advantages. We have reviewed the literature for each type of flap to determine the kind, incidence, and consequences of flap associated morbidity. In the future, tissue-engineered prefabricated free flaps might play an important role.

Bone Transplantation↗
PubMedDate not supplied

Demineralized bone matrix-induced ectopic bone formation in rats: in vivo study with follow-up by magnetic resonance imaging, magnetic resonance angiography, and dual-energy X-ray absorptiometry.

The aim of this study was to further explore the use of magnetic resonance imaging (MRI), magnetic resonance angiography (MRA), and dual-energy X-ray absorptiometry (DEXA) to assess bone formation and blood circulation in a pedicled bone graft substitute. In 14 Wistar rats, initially 10 weeks old, heterogeneous demineralized femur bone matrix implants were wrapped in pedicled adductor thigh muscle flaps. One rat died after surgery. Subsequently, bone formation and maintenance of blood vessel functionality were evaluated in six rats 6 weeks postimplantation by means of in vivo MRI/MRA and postmortem histomorphometry. The other seven rats were left for 12 weeks, whereafter bone formation was evaluated by in vivo DEXA and postmortem histomorphometry. The results demonstrated that after 6 weeks bone formation was present in four of six animals, quantified as 42 (+/-35)% and 25 (+/-19)% by means of MRI and histomorphometry, respectively. MRA was able to show patency of the pedicles of these four rats only, which suggests that the lack of blood supply in the other two rats is the cause of the failure to form bone. In the 12-week group, histology showed increased bone formation without signs of osteolysis, which was quantified histomorphometrically to be as high as 48 (+/-15)%. DEXA failed to show bone formation. It is concluded that in vivo MRI proved to be a reliable method for monitoring ectopic bone formation in a rat model, whereas in vivo DEXA was unable to detect the implants. Furthermore, in vivo MRA proved to be a useful technique for studying the circulation of muscle flaps in this animal model.

Absorptiometry, Photon↗