Eduardo D. Rodriguez

Revascularization of human acellular dermis in full-thickness abdominal wall reconstruction in the rabbit model.

This study investigates whether human acellular dermis (Alloderm; LifeCell, Branchburg, NJ) revascularizes when used to reconstruct abdominal wall defects in rabbits. This could prove useful in infected situations in which prosthetic mesh is suboptimal. Twenty-five rabbits were randomly assigned to one of three groups: primary closure (n = 5), expanded polytetrafluoroethylene (GoreTex; W.L. Gore, Flagstaff, AZ) repair (n = 10), or AlloDerm (LifeCell) repair (n = 10). The rabbits in the primary closure group received a 7 cm × 0.5 cm full-thickness abdominal wall defect that was closed primarily. A 7 cm × 3 cm full-thickness abdominal wall defect was created in the other two groups. The defects were repaired with a GoreTex Mycromesh (W.L. Gore), or AlloDerm (LifeCell) patch. At 30 days, the following endpoints were evaluated: (1) incidence of herniation; (2) presence of intra-abdominal adhesions; (3) the breaking strength of the patch–fascial interface; and (4) evaluation of graft vascularization by fluorescein dye infusion and histological analysis. There was no incidence of herniation in any of the rabbits. Visceral adhesions to the patch were found in all animals in the Gore-Tex (W.L. Gore) group but in none in the AlloDerm (LifeCell) group. The size of the patch was unchanged in all the rabbits except for two rabbits in the AlloDerm (LifeCell) group that stretched 1 cm in the transverse dimension. The change in size was not statistically significant (p = 0.17) when compared with the change in size in the Gore-Tex (W.L. Gore) group. The mean breaking strength of the primary closure group was significantly higher (521.2 N/mm2 ± 223.0) than that of the two patch-repair groups (p < 0.05). But there was no significant difference between the mean breaking strength of the AlloDerm (LifeCell) fascial interface (288.6 N/mm2 ± 97.1 SD) and that of the Gore-Tex (W.L. Gore) fascial interface (337.0 N/mm2 ± 141.2). Fluorescein dye infusion and histological analysis confirmed vascularization of the AlloDerm (LifeCell) graft. This study demonstrates that AlloDerm (LifeCell) does become vascularized when used as a fascial interposition graft for abdominal wall reconstruction. AlloDerm (LifeCell) also performs mechanically as effectively as Gore-Tex (W.L. Gore) in ventral hernia repair at 1 month after operation in the rabbit model.

Recurrent abdominal laxity following interpositional human acellular dermal matrix.

Repair of large complex abdominal hernias with significant loss of domain requires component separation in combination with either a synthetic or biologic interpositional material. We previously described an algorithm for complex abdominal hernia repair, which incorporates Alloderm as an interpositional material and selective use of prolene mesh as an overlay. We now report recurrent laxity in a series of patients who were repaired with interpositional Alloderm alone without prolene mesh overlay. We reviewed all patients who underwent repair of massive ventral hernias and identified 7 patients who presented with abdominal wall laxity following component separation with interpositional Alloderm alone. All patients developed laxity within 12 months and required a secondary procedure. At the time of re-exploration, severe attenuation in the Alloderm was noted. The segment was excised, the edges closed primarily, and prolene mesh was placed as an onlay. Although Alloderm has been reported to be an effective biologic material for abdominal hernia reconstruction, we have noted significant laxity requiring secondary intervention.

Clinical outcomes in cranioplasty: risk factors and choice of reconstructive material.

Background: Continuing advances in cranioplasty have enabled repair of increasingly complicated cranial defects. However, the optimal materials and approaches for particular clinical scenarios remain unclear. This study examines outcomes following cranioplasty for a variety of indications in patients treated with alloplastic material, autogenous tissue, or a combination of both. Methods: The authors conducted a retrospective analysis on 180 patients who had 195 cranioplasties performed between 1993 and 2010. Results: Materials used for cranioplasty included alloplastic for 42.6 percent (83 of 195), autologous for 19.0 percent (37 of 195), and both combined for 38.5 percent (75 of 195). Mean defect size was 70.5 cm2. A subset of patients had undergone previous irradiation (12.2 percent; 22 of 180) or had preoperative infections (30.6 percent; 55 of 180). The most common complication was postoperative infection (15.9 percent; 31 of 195). Factors that significantly predisposed to complications included preoperative radiation, previous infection, and frontal location. Preoperative radiation was the strongest predictor of having any postoperative complications, with an adjusted odds ratio of 6.91 (p < 0.005). Irradiated patients (OR, 7.96; p < 0.05) and patients undergoing frontal cranioplasties (OR, 2.83; p < 0.05) were more likely to require repeated operation. Preoperative infection predisposed patients to exposure of hardware in alloplastic reconstructions (OR, 3.13; p < 0.05). Conclusions: Despite the evolution of cranioplasty techniques and materials, complications are not uncommon. The choice of reconstructive material may modify the risk of developing postoperative complications but appears less important than the clinical history in affecting outcome. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.

Abdominal wall reconstruction following severe loss of domain: the R Adams Cowley Shock Trauma Center algorithm.

Background: Large, complex, posttraumatic and recurrent abdominal hernias present a reconstructive challenge. Multiple techniques have been described to restore the integrity of the abdominal wall, although the indications and applications can be difficult to navigate. The authors propose an algorithm that facilitates the assessment and treatment of secondary large ventral defects. Methods: The algorithm described involves a systematic approach to abdominal wall reconstruction and was applied to 23 consecutive patients at the R Adams Cowley Shock Trauma Center. Data collected from the chart review included age, body mass index, mechanism of injury, placement of skin graft and use of resorbable mesh before definitive reconstruction, size of defect, number of tissue expanders placed, length of follow-up, and complications. Results: There were six female patients and 17 male patients, with an average age of 36 years. The average follow-up was 7 months. Seventeen patients had posttraumatic laparotomies, five patients had aggressive abdominal wall debridement following necrotizing fasciitis, and one patient developed a large abdominal wall hernia following complications from gastric bypass surgery. All patients underwent delayed abdominal wall reconstruction, with an average time to initial reconstruction of 19.5 months. Sixteen patients had no postoperative complications. Seven patients had complications, including one with an enterocutaneous fistula, one with a partial small bowel obstruction, two with seromas, one with a superficial wound infection, and two with recurrent abdominal wall laxity. Conclusions: The reconstructive ladder for large, complex abdominal hernias is poorly defined. The proposed algorithm provides a systematic staged approach that incorporates available techniques used for delayed reconstruction of the abdominal wall.

An Anatomical Study of External Carotid Artery Vascular Territories in Face and Midface Flaps for Transplantation

Background: The technical success of facial composite tissue allotransplantation demands full understanding of superficial and deep perfusion for reliable microvascular transfer. Candidates with composite midface defects require an appreciation of the circulatory patterns to design a composite midface allotransplant. Methods: External carotid vascular territories were evaluated in 10 cadavers to determine the reliability of facial soft-tissue flaps based on a single vascular pedicle. The right common carotid artery was injected with red latex and the left was injected with blue latex. Dual perfusion was confirmed by purple, following two-color mixing. Vascular pedicles included the superficial temporal, transverse facial, and facial arteries. In five additional cadavers, the midface segment was isolated by Le Fort III osteotomy after two-color latex injection with inclusion of the internal maxillary vascular pedicle. Cadavers were imaged with three-dimensional computed tomographic reconstructions following latex injection to confirm perfusion patterns. Results: In soft-tissue facial flaps, unilateral carotid dominance was seen in the nasal dorsum and tip, confirming reliable supply by a single external carotid artery. In midface flaps, bilateral perfusion was seen in the maxilla. Ipsilateral perfusion was observed at the zygomaticomaxillary complex without any contralateral contribution. Conclusions: Dual soft-tissue perfusion was confirmed in most specimens at the nasal, central face, and maxilla. The inclusion of the maxilla in the design of a facial composite allotransplant demands bilateral vascular pedicles based on the internal maxillary arteries. The authors highlight a procurement strategy for design of such flaps.

Total face, double jaw, and tongue transplant simulation: a cadaveric study using computer-assisted techniques.

Background: With the transplantation of more extensive facial vascularized composite allografts, fundamental craniofacial and aesthetic principles become increasingly important. In addition, computer-assisted planning and intraoperative navigation may improve precision and efficiency in these complex procedures. Methods: Ten mock face transplants were performed in 20 cadavers. The vascularized composite allograft consisted of all facial skin, mimetic muscles, the tongue, the midface by means of a Le Fort III osteotomy, and the mandible by means of sagittal split osteotomies. Craniofacial computed tomographic scans were obtained before and after the mock transplants. Surgical planning software was used to virtually plan the osteotomies, and a surgical navigation system guided the osteotomies intraoperatively. Cephalometric analyses were compared between the virtually planned transplants and the actual postoperative results. Results: The combination of preoperative computerized planning and intraoperative guidance consistently produced a vascularized composite allograft that could be easily fixated to the prepared recipient, with only minimal burring of osteotomy sites necessary. Satisfactory occlusion was maintained, and postoperative computed tomography confirmed accurate skeletal fixation. Insignificant differences with regard to cephalometric analyses were noted when predicted and actual postoperative data were compared. Conclusions: The authors’ experience treating severe craniofacial injury allowed consistent transfer of facial vascularized composite allografts, maintaining proper occlusion. Preoperative computer planning and intraoperative navigation ensured precise osteotomies and a good donor-recipient skeletal match, which greatly reduced the need for intraoperative adjustments and manipulation. This total facial vascularized composite allograft represents one of the most extensive described and is intended to represent a typical central facial demolition pattern.

The effect of arthrocentesis of the temporomandibular joint in patients with rheumatoid arthritis

PURPOSE This study evaluated the objective and subjective changes in a group of rheumatoid arthritic (RA) patients with temporomandibular joint (TMJ) complaints who were subjected to joint lysis and lavage. PATIENTS AND METHODS Twelve females with previous documented RA underwent baseline assessment with erythrocyte sedimentation rate, physical examination of TMJ function, and a visual analog pain scale (VAPS). The VAPS and jaw function changes were recorded at 2-week intervals for 6 weeks after lysis and lavage under local anesthesia in an ambulatory setting. RESULTS All patients showed statistically significant post-treatment improvement in their pain, and function was enhanced. CONCLUSION TMJ arthrocentisis is a useful adjunct in the short-term management of the symptoms of rheumatoid arthritis.

Critical computed tomographic diagnostic criteria for frontal sinus fractures

PURPOSE Diagnosis and treatment of frontal sinus fractures (FSFs) have progressed over the previous 30 years. Despite advances in computed tomography, there is no current diagnostic uniformity with regard to classification and treatment. We developed a statistically valid treatment protocol for FSFs based on injury pattern, nasofrontal outflow tract (NFOT) injury, and complication(s). These data outlined predictable injury patterns based on specific computed tomographic findings critical to the diagnosis and ultimate treatment of this potentially fatal injury. MATERIALS AND METHODS A retrospective review was conducted on patients with FSF from 1979 to 2005 under institutional review board approval. All computed tomographic scans were reviewed by the authors and fractures categorized by location, displacement, comminution, and degree of NFOT injury. RESULTS One thousand ninety-seven patients with FSF were identified, 87 expired and 153 had inadequate data, leaving a group of 857 patients. Simultaneous displacement of anterior-posterior tables constituted the largest group (38.4%). NFOT injury occurred in most patients (70.7%) and was strongly associated with anterior (92%) and posterior (88%) table involvement (comminuted 98%). Sixty-seven percent of patients with NFOT injury had obstruction. Five hundred four patients (59.6%) had surgery with 10.4% complications and 353 patients were observed with 3.1% complications. All but 1 patient with complications had NFOT injury (98.5%). CONCLUSIONS Predictable patterns of injury based on specific computed tomographic data play a pivotal role in classification and surgical management of potentially fatal frontal sinus injuries. Radiologic diagnosis of NFOT injury in FSFs, particularly obstruction, plays a decisive role in surgical planning.

Long-term impact of damage control laparotomy: a prospective study.

HYPOTHESIS Damage control laparotomy (DCL) has beneficial effects on the long-term morbidity and survival of trauma patients. DESIGN Prospective study. SETTING Level I trauma center. PATIENTS Eighty-eight trauma patients who were admitted during a 3-year period (January 1, 2000, through December 31, 2003) underwent damage control laparotomy and were subsequently followed up (January 1, 2001, through December 31, 2008). INTERVENTION Damage control laparotomy. MAIN OUTCOME MEASURES Major and long-term complications, lengths of stay, mortality, readmissions, subsequent surgical procedures, activities of daily living, and return to work. RESULTS On admission, the mean age and Injury Severity Score were 33 years and 34, respectively. Of the 88 patients, 66 (75%) were male; 46 patients had blunt injuries and 42 had penetrating injuries. Liver was the most common injury (63 patients), followed by bowel (34), spleen (33), major vessel (19), and pancreas (10). The mean admission pH and temperature were 7.19 and 34.4°C, respectively, with 21.5 U of packed red blood cells transfused. The mean (SD) number of initial abdominal operations was 4.6 (2.5) per patient, with an overall mortality of 28% (25 patients). Intensive care unit and hospital lengths of stay were 18 (15) and 32 (20) days, respectively. Of the 63 patients who survived, 58 underwent intra-abdominal closure with polyglactin mesh. During the study, 44 intra-abdominal infections and 18 enterocutaneous fistulas were diagnosed. All 63 survivors were readmitted at least once. There were a total of 186 readmissions and 92 subsequent surgical procedures. Ventral hernia repair (66 readmissions) was the most common reason for readmission, followed by infection (41) and fistula management (29). There was 0% mortality for patients who survived the preliminary hospitalization. Of the 63 surviving patients, 51 (81%) reported that they had gone back to work and resumed normal daily activities. CONCLUSION Although damage control laparotomy is associated with a significant complication and readmission rate, its overall benefit is indisputable.

Abdominal ventral hernia repair with current biological prostheses: an experimental large animal model.

Biologic prostheses have emerged to address the limitations of synthetic materials for ventral hernia repairs; however, they lack experimental comparative data. Fifteen swine were randomly assigned to 1 of 3 bioprosthetic groups (DermaMatrix, AlloDerm, and Permacol) after creation of a full thickness ventral fascial defect. At 15 weeks, host incorporation, hernia recurrence, adhesion formation, neovascularization, inflammation, and biomechanical properties were assessed. No animals had hernia recurrence or eventration. DermaMatrix and Alloderm implants demonstrated more adhesions, greater inflammatory infiltration, and more longitudinal laxity, but near identical neovascularization and tensile strength to Permacol. We found that porcine acellular dermal products (Permacol) contain following essential properties of an ideal ventral hernia repair material: low inflammation, less elastin and stretch, lower adhesion rates and cost, and more contracture. The addition of lower cost xenogeneic acellular dermal products to the repertoire of available acellular dermal products demonstrates promise, but requires long-term clinical studies to verify advantages and efficacy.