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Christoph Heitmann

Publications and source records attributed to Christoph Heitmann.

14 recordsLinked to original sources
PubMed2006

Outcome assessment after reconstruction of complex defects of the forearm and hand with osteocutaneous free flaps.

BACKGROUND: Complex defects of the forearm and hand often require microvascular reconstruction with osteocutaneous free flaps for limb salvage. METHODS: Fifteen patients with osseous and soft-tissue defects of the forearm and hand were treated with osteocutaneous flaps (1992 to 2004) and evaluated for postoperative results. Assessment focused on range of motion, pain, grip strength, and Disabilities of Arm, Shoulder, and Hand questionnaire score. Donor- and recipient-site morbidity was documented. RESULTS: The defects resulted from trauma, infection, or malignancy. Reconstruction was possible by microvascular osteoseptocutaneous fibula transplantation (n = 8), osteocutaneous scapular or parascapular flaps(n = 6), and osteocutaneous lateral arm flap (n = 1). The average patient age was 38 years. The median osseous defect was 11.7 cm, and all patients needed additional soft-tissue reconstruction. All defects could be reconstructed in a one-step procedure after serial débridement or oncologic resection. Patients' hand function was markedly reduced compared with the unaffected extremity, but functional results were still satisfactory, with a mean Disabilities of Arm, Shoulder, and Hand score of 25.3 reflecting a moderate disability in activities of daily living. Two patients developed pseudarthrosis, and one had to undergo an ablation procedure because of persistent infection. Two patients developed wound dehiscence at the donor site, and one patient required a fasciotomy due to an imminent compartment syndrome after fibula harvest. For all patients, the functional results were acceptable when the potential alternatives were taken into consideration. This was also reflected by a high individual satisfaction rate. CONCLUSION: This analysis demonstrates that limb salvage with osteocutaneous free flaps is the treatment of choice for three-dimensional defects of the forearm and hand.

Bone Transplantation↗
PubMed2004

Side-to-side sutureless vascular anastomosis with magnets.

OBJECTIVE: Abbe and Payr introduced vascular techniques and devices to facilitate vessel anastomosis over a century ago. Obora published the idea of a sutureless vascular anastomosis with use of magnetic rings in 1978. The purpose of this study was to assess the performance of a new magnetic device to perform a side-to-side arteriovenous anastomosis in a dog model. MATERIAL AND METHODS: Male fox hounds (25 kg) were treated preoperatively and daily postoperatively with clopidogrel bisulfate (Plavix) and aspirin. The femoral artery and vein were exposed unilaterally in 3 dogs and bilaterally in 4 dogs (n = 11 anastomoses). A 4-mm arteriotomy was performed, and 1 oval magnet 0.5 mm thick was inserted into the lumen of the artery and a second magnet was applied external to the artery, compressing and stabilizing the arterial wall to create a magnetic port. An identical venous magnetic port was created with another pair of oval magnets. When the 2 ports were allowed to approach each other, they self-aligned and magnetically coupled to complete the arteriovenous anastomosis. Patency was assessed for the first hour with direct observation, again after 9 weeks with duplex ultrasound scanning, and at 10 weeks under direct open observation. The anastomoses were explanted after 10 weeks. Hydrodynamic resistance was measured ex vivo on the final 8 anastomoses by measuring the pressure drop across an anastomosis with a known flow rate. RESULTS: After implantation, very high flow created visible turbulence and palpable vibration. All 11 anastomoses were patent under direct observation and palpation. Ten of 11 anastomoses were clearly patent on duplex scans, and patency of 1 anastomosis was questionable. Hydrodynamic resistance averaged 0.73 +/- 0.33 mm Hg min/mL (mean +/- SEM). CONCLUSIONS: Vascular anastomoses performed with magnets demonstrated feasibility; exhibited 100% patency after 10 weeks in a dog arteriovenous shunt model; lacked apparent aneurysm or other potentially catastrophic failure; demonstrated remodeling of the vessel wall after several weeks to incorporate the magnets, making the magnetic force unnecessary; and warrants further study in vessels with different sizes, flow rates, and locations. CLINICAL RELEVANCE: We present a magnet-based device used to perform side-to-side peripheral vascular anastomoses. Its advantages include the ability to anastomose vessels without requiring circumferential surgical exposure. Vascular anastomosis performed with these magnets demonstrated 100% patency in the dog, lacked apparent aneurysm or other potentially catastrophic failure, and demonstrated remodeling of the vessel wall after several weeks, to incorporate the magnets, making indefinite retention of field strength unnecessary. This technique could enable minimally invasive procedures, such as complex reconstructive and revascularizing surgery, and warrants further study in vessels with different sizes, flow rates, and locations.

Animals↗
PubMed2004

Reduction of skeletal muscle injury in composite tissue allotransplantation by heat stress preconditioning.

Ischemia-reperfusion injury is a dominant factor limiting tissue survival in any microsurgical tissue transplantation, a fact that also applies to allogeneic hand transplantation. The clinical experience of the 12 human hand transplantations indicates that shorter ischemia times result in reduced tissue damage and, ultimately, in better hand function. Heat stress preconditioning and the accompanying up-regulation of the heat shock protein 72 have been shown to reduce the ischemia-reperfusion injury following ischemia of various organs, including organ transplantation. The aim of this study was to reduce the ischemia-reperfusion injury in a model of composite tissue allotransplantation. Allogeneic hind limb transplantations were performed from Lewis (donor) to Brown-Norway rats. Donor rats in group A (n = 10) received a prior heat shock whereas rats in group B (n = 10) did not receive any prior heat shock. Group C served as a control group without transplantation. The transplantations were performed 24 hours after the heat shock, at which time the heat shock protein 72 was shown to be up-regulated. The outcome was evaluated 24 hours after transplantation by nitroblue tetrazolium staining and wet-to-dry weight ratio of muscle slices (anterior tibial muscle). The nitroblue tetrazolium staining showed a significant reduction of necrotic muscle in group A (prior heat shock) (p = 0.005). The wet-to-dry ratio was significantly reduced in group A (prior heat shock), indicating less muscle edema and less tissue damage (p = 0.05). Heat shock preconditioning 24 hours before an ischemic event leads to an up-regulation of heat shock protein 72 in muscle and to a tissue protection reducing ischemia-reperfusion injury in composite tissue transplantation.

Animals↗
PubMed2003

Restoration of thumb sensibility with the innervated first dorsal metacarpal artery island flap.

PURPOSE: This study investigated the quality of sensibility from innervated first dorsal metacarpal artery (FDMCA) island flaps in younger and older patients and evaluated the donor site morbidity at the index finger. METHODS: Twenty-five patients with an innervated FDMCA island flap to restore sensibility of the thumb were divided into groups according to age (>50 or <50 years). Sensory recovery and cortical reorientation were tested with Semmes-Weinstein monofilaments, a calibrated 2-point discrimination tester, and needle prick testing. Donor site morbidity was evaluated for range of motion, aesthetic appearance, pain, and problems with injuries. RESULTS: The mean age of the patients was 48.3 years and the mean follow-up period was 3 years. The 14 patients older than 50 years had a static 2-point discrimination (s2-PD) of 10.9 mm compared with 10.8 mm of the 11 patients younger than 50 years. The average loss of s2-PD of the flap compared with the donor area averaged 2.7 mm in all patients. Complete cortical reorientation occurred in 7 patients older than 50 years and in 5 patients younger than 50 years. Total loss of range of motion of all donor finger joints was 14 degrees (4.4%) compared with the contralateral index finger. Twenty-two patients were satisfied with the result. CONCLUSIONS: There were no age-related differences in the surgical results of the innervated FDMCA island flap and the donor site morbidity was negligible.

Adult↗
PubMed2003

Vasculature of the peroneal artery: an anatomic study focused on the perforator vessels.

Based on the dissection of 20 fresh cadaver legs, the authors have further defined the vascular anatomy of the peroneal artery and its cutaneous perforator vessels. They identified a total of 95 cutaneous perforators of the peroneal artery greater then 0.3 mm in 20 legs. The average number of cutaneous perforators was 4.8 (range: three to seven) per leg. The cutaneous perforators were either musculocutaneous (34 percent) or septocutaneous (66 percent). The musculocutaneous perforators were found predominantly in the upper two-thirds of the lower leg; the septocutaneous perforators were located in the lower two-thirds of the leg. The external diameter of the cutaneous perforators at the posterior border of the fibula was 0.6 (range: 0.3 to 1.5) mm. The blood supply of the proximal fibula epiphysis and fibula head was found not to be in the vascular territory of the peroneal artery. These results are the basis of the established osteoseptocutaneous fibula transfer, the peroneal fasciocutaneous free flap, and the double-paddle peroneal tissue transfer that all require dissection of highly vascularized tissue adjacent to the fibula, in order to reach the peroneal vessels. These constant anatomic findings should encourage the surgeon to harvest skin flaps just to the level of the posterior border of the fibula, thereby creating perforator flaps based on the peroneal system.

Arteries↗
PubMed2003

Tissue expansion.

Tissue expansion in the upper extremity is a valuable technique with expanding indications and expected outcomes. The primary indications are coverage problems after trauma, but the technique is also applicable to defects caused by treatment of hemangioma, nevi, tattoos, or hypertrophic scars as well as correction of unstable tissue or as an alternative to free tissue transfer. The advantage of expansion-specifically, match in tissue texture and retention of sensibility-may be more important in the hand and upper extremity than in other areas. The inevitable capsule that forms around the expander does provide a smooth gliding surface for tendons in the forearm and wrist. In conclusion, tissue expansion of the upper extremity offers the surgeon the ability to improve cosmesis in one location without having to sacrifice cosmesis at a second site.

Journal Article↗
PubMed2003

Applications of the vascularized fibula for upper extremity reconstruction.

There are limited reconstructive options for segmental bone defects of the upper extremity larger than 6 cm in length, especially when associated with soft-tissue loss. Among the limited treatment options the osteoseptocutaneous fibular transplant is well established. The anatomy is reliable, the blood supply is constant, and the operative technique can be standardized. The advantage of including skin with the vascularized fibular transplant is twofold. First, the skin paddle can be used to augment the soft-tissue envelope. Second, the skin paddle serves as a monitor, providing an immediate, ongoing, and reliable method to monitor the blood flow to the graft. The osteoseptocutaneous fibular transplant proved to be an effective treatment of combined segmental bony and soft-tissue defects of the forearm and humerus.

Journal Article↗
PubMed2003

Extended TRAM flap: feasibility study on fresh human cadavers.

The purpose of this study was to investigate the feasibility of a superiorly based TRAM flap for breast reconstruction with its superior border abutting the inframammary fold. This flap would have a primary blood supply from the superior epigastric vessels, similar to a free flap attached to the mammary system. This flap, however, would not require microsurgery. Instead, it would have its superior epigastric pedicle lengthened by partial rib resection. Donor site closure would be accomplished by reverse abdominoplasty and the donor scar hidden in the inframammary fold. The surgical anatomy of such an extended TRAM flap (eTRAM) was investigated by cannulation of the internal mammary artery (IMA) in 10 fresh human cadavers bilaterally, injection with latex, and then dissection throughout its intrathoracic course. At the level of the third intercostal space, the mean external diameters of the right and left IMA were found to be 2.5 mm and 2.3 mm, respectively. The diameter of the vessel decreased until the IMA bifurcated into the superior epigastric artery and the musculophrenic artery, usually at the sixth intercostal space. The superior epigastric artery, having a mean diameter of 1.6 mm at its origin, descended caudally behind the seventh costal cartilage and could be followed until it entered the posterior rectus sheath and the rectus abdominis muscle. On its downward course, it was not embedded in the diaphragm muscle and was easily separated without violation of the thoracic cavity. From this anatomic study, it seems to be possible to raise an eTRAM after partial rib resection. Some technical considerations of such a flap are discussed. This modification of the TRAM would be helpful to surgeons commonly performing pedicled TRAM flaps and might extend its applicability beyond breast reconstruction to chest wall, intrathoracic, and head and neck reconstruction.

Cadaver↗
PubMed2003

The thoracodorsal artery perforator flap: anatomic basis and clinical application.

Based on the dissection of 20 fresh cadavers, the authors have detailed further the vascular anatomy of the thoracodorsal artery and its cutaneous perforator vessels. The thoracodorsal artery showed a constant bifurcation into a horizontal branch and a lateral branch, located on the deep surface of the latissimus dorsi muscle 4 cm (range, 3-6 cm) distal to the inferior scapular border and 2.5 cm (range, 1-4 cm) medial to the lateral free margin of the muscle. In 20 specimens there was a total of 64 musculocutaneous perforators larger than 0.5 mm. Thirty-six perforators (56%) originated from the lateral branch and 28 perforators (44%) originated from the horizontal branch. All perforators originated within a distance of 8 cm from the neurovascular hilus and ran in proximity with the horizontal or lateral branches. In 11 dissections (55%) there was also a direct cutaneous branch originating from the extramuscular course of the thoracodorsal artery before the neurovascular hilus. This cutaneous branch did not pierce the latissimus muscle but rounded the lateral muscle edge and supplied the overlying subcutaneous tissue and skin. It is hoped that the constant anatomy will encourage surgeons in the future to use the thoracodorsal artery perforator flap more often.

Adult↗
PubMed2003

Musculoskeletal sepsis: principles of treatment.

Musculoskeletal sepsis is infection of bone, joints, muscles, and skin and often occurs after open fractures. Thus, the main objective in the treatment of open fractures in restoration of function and prevention of infection. It is important to consider all open fracture wounds as contaminated. The principles of open fracture treatment include taking appropriate cultures, instituting immediate systemic antibiotic therapy, surgical débridement and wound management, stabilizing the fracture, and early bone grafting when indicated. The open tibial fracture, classified according to Gustilo and Anderson, serves as an exemplary model for musculoskeletal sepsis because this type of injury is described extensively in the literature. Early diagnosis and effective surgical and antibiotic management can control musculoskeletal sepsis, and the suppression of infection may last a lifetime.

Anti-Bacterial Agents↗
PubMed2002

Alternatives to thumb replantation.

LEARNING OBJECTIVES: After studying this article, the participant should: 1. Have a variety of options for thumb reconstruction. 2. Know the advantages and disadvantages of the nonmicrosurgical and microsurgical techniques for thumb reconstruction. 3. Understand the decision making from the variety of thumb reconstruction techniques based on patient needs. 4. Have a basic understanding of the various thumb reconstruction techniques discussed. The traumatic amputation of the thumb is an absolute indication for attempted replantation. The profound disability of the hand resulting from absence of the thumb, with loss of pinch and grasp, obliges the surgeon to make every attempt to replant the amputated thumb and preserve hand function. However, not all attempts at replantation result in survival of the amputated portion, and unreconstructable damage to or complete loss of the amputated part may preclude attempted replantation. In such situations, the surgeon must have alternative methods of dealing with the sequelae of thumb loss. This article will discuss nonmicrosurgical and microsurgical techniques for thumb reconstruction.

Amputation, Traumatic↗
PubMedDate not supplied

Treatment of deep infections of the shoulder with pedicled myocutaneous flaps.

Infection after reconstruction of the shoulder can lead to significant morbidity and possible destruction of the glenohumeral joint. Often, seemingly small wound problems mask underlying soft-tissue deficiency and instability. We have reviewed our experience with deep infections of the shoulder that have been treated with pedicled myocutaneous flaps. Patients in this series had been treated by a variety of local measures including debridement and attempts at reclosure, often unsuccessfully. The ability to import well-vascularized tissue that can treat dead space as well as reestablish a new cutaneous envelope around the shoulder is desirable and indicated for these difficult cases. Surprisingly, even with exposure of the humeral head in the wound, the shoulder joint can be salvaged by use of the techniques described in this article.

Adult↗