Faculty Bibliography

BACKGROUND: Adjuvant chemotherapy is often required for the treatment of bone cancers after tumor resection, which often results in a large continuity defect. The immunosuppressive side effects could instead be exploited to allow immediate reconstruction with a composite tissue allograft (CTA) that would provide for replacement of tissues. We used a short course of doxorubicin to achieve a novel method of immunosuppression in a rat model undergoing CTA to create an immunological environment for allograft survival. MATERIALS & METHODS: The Institutional Animal Care and Use Committee-approved protocol consisted of 3 experimental groups. Groups 2 and 3 consisted of Brown Norway rats (n = 5) as allograft donors and Lewis rats (n = 5) as transplant recipients. An abdominal wall CTA was harvested off the superficial inferior epigastric vessels. Doxorubicin therapy was administered in group 3 animals. Survival of the CTA was assessed by physical examination and histological analysis. RESULTS: Allotransplant without treatment showed complete clinical and histologic rejection by day 7. Allotransplant rats treated with doxorubicin had clinically and histologically normal grafts through day 10. Kaplan-Meier survival analysis showed a statistically significant difference, with increased CTA survival time to end point with doxorubicin treatment, from a mean of 8.8 days in group 2 to 16.4 days in group 3. CONCLUSIONS: Allotransplant flaps without treatment developed complete clinical and histological rejection. The allotransplant group which received doxorubicin showed a delay of allograft rejection with an 86% increased CTA graft survival time. This demonstrates the feasibility of the immunosuppression side effect caused by chemotherapy to prevent rejection of a CTA.

The role of vascularized bone marrow in promoting composite allograft survival can be assessed by intrinsically chimeric flaps. In this study, we introduce a significant modification to a previously described rat model of combined superficial inferior epigastric artery (SIEA) myocutaneous/vascularized femur transplantation. We previously noted autocannibalization in orthotopic myocutaneous SIEA allotransplants, which complicated clinical and histologic evaluation of rejection. We therefore designed syngeneic experiments in eight Lewis (RTl(1) ) rat pairs to explore the feasibility of tunneling the SIEA component of chimeric SIEA myocutaneous/vascularized femur flaps to the recipient dorsum. Vascularized SIEA myocutaneous/femur transplants survived in their entirety to POD 63 study endpoint with patent anastomoses in seven of eight (87.5%) transplants as confirmed clinically, histologically, and via near-infrared fluorescent angiography. Tunneling of the SIEA component of SIEA myocutaneous/vascularized femur flaps to the recipient dorsum can be achieved with high success rate and acceptable operative times, and is a technically easy method to study the role of vascularized bone marrow in composite allografts. This modification facilitates SIEA component monitoring, removes it from constant contact with cage bedding, and places it in a location where autocannibalization is unlikely.

BACKGROUND: Injuries to the face can potentially lead to destruction of vital structures, with devastating sequelae to the patient. Facial fractures, especially of the midface, are often complicated by ocular injuries. The purpose of this study was to systematically review the literature to better understand specific fracture patterns associated with ocular injuries, including visual impairment and blindness. METHODS: The PubMed, EMBASE, and Cochrane databases from January of 2004 to April of 2010 were systematically reviewed to identify relevant studies. Only those that investigated facial fractures with concomitant ocular injuries, visual impairment, and/or blindness were included. Studies that described nonfacial fractures or those that only focused on the function of extraocular muscles were excluded. Case reports, nonsystematic reviews, and studies with fewer than 10 patients were also excluded. RESULTS: Eleven articles met study criteria and were included for analysis. There were a total of 14,535 patients, with an average of 1211 patients (range, 39 to 4426) per study. Level of evidence included levels II (n = 1 study), III (n = 1), and IV (n = 9). The mean reported rate of acute visual loss was 1.7 percent. Periorbital and orbital blowout fractures were more often complicated by ocular injuries compared with other facial fracture patterns. High-impact zygomatic fractures were most commonly associated with blindness. CONCLUSIONS: Existing studies exploring ocular injuries, visual impairment, and blindness associated with facial fractures offer conflicting data. Specifically directed studies are required so that significant correlations between specific fracture patterns and specific ocular injuries can be drawn. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, IV.

A 6-year-old girl presented with a large recalcitrant oronasal fistula after bilateral cleft lip and palate repair and numerous secondary attempts at fistula closure. Incomplete palmar arches precluded a free radial forearm flap. A free vastus lateralis muscle flap was successfully transferred. No fistula recurrence was observed at 18 months. There was no perceived thigh weakness. The surgical scar healed inconspicuously. Free flaps should no longer be considered the last resort for treatment of recalcitrant fistulas after cleft palate repair. A free vastus lateralis muscle flap is an excellent alternative, and possibly a superior option, to other previously described free flaps.

Craniofacial defects are often associated with 3-dimensional volumetric contour deficiencies. The free groin flap was historically popular though technical limitations subsequently caused its use to fall from favor. We sought to determine if a role remained for the free groin flap in aesthetic craniofacial reconstruction. From May 2005 to July 2010, 15 patients had 18 consecutive free groin flaps performed by the senior surgeon at the R Adams Cowley Shock Trauma Center and the Johns Hopkins Medical Institute. Data collected included age, sex, operative date, etiology, defect size, recipient vessels, complications, donor-site closure, and follow-up time. Eighteen groin flaps were used for the patient cohort consisting of 10 males and 5 females (mean age, 26 years; range, 18-40 years) who underwent reconstruction necessitated by various oncologic, traumatic, infectious, and congenital etiologies. The average defect size was 7.3 x 6.3 cm (range, 3-10 x 1-10 cm). Seventeen flaps were based on the superficial circumflex iliac vessels and 1 on the superficial inferior epigastric vessels. Seventeen flaps used the superficial temporal artery and vein as the recipient vessels, and the remaining flap used the superior thyroid artery and retromandibular vein. Of the 18 flaps, 17 survived (94% survival rate). All donor sites were closed primarily. Follow-up time ranged from 6 to 60 months. The free groin flap is generally underused in the reconstruction of complex craniofacial facial defects. Its unique characteristics and minimal donor-site morbidity should prompt the reconstructive surgeon to retain the free groin flap in his or her armamentarium.

Bisphosphonates (BPs) are the standard of care for patients with metastatic cancer and multiple myeloma to prevent skeletal complications (e.g., severe bone pain, pathologic fracture, etc.) and to treat osteoporosis. The cause and effect relationship between BPs and BP-related osteonecrosis of the jaws (BRONJ) is not well established. Current research suggests that bacterial biofilms may play a significant role in the pathogenesis of BRONJ. Recently, we have shown that BRONJ lesions are heavily colonized by oral bacteria and present many clinical challenges as they are difficult to culture and antibiotic resistance may result in misguided antibiotic therapy. Here we highlight the crosstalk among the oral bacteria and host immune response in BRONJ subjects. Using 16S rDNA molecular technique we characterize the total bacterial profile of BRONJ, BP and control subjects. Denaturing gradient gel electrophoresis cluster analysis revealed three clusters each representing the three groups, control, BP and BRONJ indicating that the microbiome present in tissue samples was distinct to each group. DGGE band pattern indicated that the BRONJ group had less bacterial diversity as compared to control indicating that high abundance of specific bacteria colonizing the BRONJ lesion. 16S sequencing and clonal analysis showed 6 phyla in all three groups. The phylum Firmicutes was predominant in BRONJ group (72%) followed by BP group (70%) as compared to control group (59%). The Chi-square test also showed significant differences in percent relative distribution of phyla, between control/BP groups (p<0.001), control/BRONJ (p<0.001) and BP/BRONJ (p<0.05). There was significantly increase in the gram positive bacteria in BRONJ group. PCR Array analysis indicated that the host genes responsible for antibacterial response such as MPO, CTSG, and NOD2 were significantly down regulated. Deficient innate immune responses to microorganisms together with poor healing and repair provide continuous opportunities for expanding!

BACKGROUND: Facial synkinesis comprises unwanted facial muscle contractions in different facial muscle groups following voluntary ones, in cases of incomplete recovery from facial paralysis. Facial expressivity and function are impaired, and the psychological integrity of the patients is seriously affected. METHODS: Thirty-one adult patients (older than 18 years) presenting with post-facial paralysis synkinesis were included in this study. The mean patient age was 39.6 years and the mean denervation time was 124 months. RESULTS: There were five patient groups. Group A (n = 9) underwent cross-facial nerve grafting and secondary microcoaptations. Group B (n = 8) had cross-facial nerve grafting, secondary microcoaptations, and botulinum toxin type A injections. Group C (n = 6) received cross-facial nerve grafting, secondary microcoaptations, botulinum toxin type A, and selective neurectomies. Group D (n = 2) underwent cross-facial nerve grafting, direct muscle neurotization, and botulinum toxin type A. Group E underwent other means of treating synkinesis (n = 6), such as botulinum injections alone (n = 1), biofeedback alone (n = 2), biofeedback with selective neurectomies and myectomies (n = 2), and biofeedback and botulinum injections (n = 1). Group B had the highest synkinesis improvement (100 percent), followed by groups A and C (66 percent). Functional results were improved, with smile improvement being higher in group C and eye closure being higher in groups A, B, and E. CONCLUSION: Meticulous patient selection and evaluation followed by an individualized form of treatment, most frequently including cross-facial nerve grafting and secondary microcoaptations along with botulinum toxin type A and biofeedback including facial muscle retraining, constitute an effective and reliable methodology with which to combat post-facial paralysis synkinesis. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Although elbow extension is facilitated by gravity, triceps muscle provides elbow joint stability; in patients with brachial plexus injuries stable elbow is necessary for obtaining useful hand function. This study presents the senior author's experience with triceps nerve reconstruction and the functional results in patients with brachial plexus injuries. Outcomes were analyzed in relation to denervation time, severity score, length of the interposition nerve graft and donor nerves used. One hundred and sixty two patients with brachial plexus injury had triceps nerve neurotization and elbow extension recovery between 1978 and 2006. The mean patient's age was 25.45 +/- 9.90 years and the mean denervation time was 16.90 +/- 26.95 months. Two hundred and thirty two motor donors were used in 156 patients; 6 patients underwent neurolysis; 86 intercostal nerves were transferred in 41 patients. Interposition nerve grafts were used in 130 patients. Results were good or excellent in 31.65% of patients. The age of patients and the severity of the brachial plexus lesion are among the factors that significantly influenced functional results. Intraplexus motor donors are always preferable achieving better functional outcomes than extraplexus donors. Intercostal nerves and the posterior division of contralateral C7 proved preferred donors for elbow extension restoration in multiple avulsions. Although it is difficult to restore strong elbow extension, triceps nerve reconstruction is suggested in brachial plexus management, since it provides elbow stability. Satisfactory elbow extension strength was restored in young patients with high severity score.