Faculty Bibliography

PURPOSE: Head and neck neoplasms requiring surgical resection of the mandible can have negative consequences on patient quality of life. For patients with segmental resections, the vascularized fibular free flap and nonvascularized iliac crest are frequently used. The fibula has surpassed the iliac crest in popularity due to the success associated with a vascularized graft; however, there still remain significant advantages with the nonvascularized graft. There has not been a study comparing the quality of life associated with these two methods of mandibular reconstruction. We carried out the following study to compare quality of life of both grafts in an attempt to help guide therapeutic decisions. PATIENTS AND METHODS: Twenty-nine patients at the University of California, San Francisco undergoing mandibular resection with subsequent reconstruction with either a vascularized fibular free flap or nonvascularized iliac crest bone graft were identified. Patient quality of life was assessed with a modified version of the University of Washington Quality of Life Questionnaire, version 4. RESULTS: Eighteen patients responded (10 reconstructed previously with a fibula, 8 with iliac crest reconstructions). Patients with an iliac crest bone graft had significantly better chewing and swallowing scores (P = .04, P = .049 respectively). There was also a trend for better taste (P = .067). When patients with a history of radiation therapy were excluded, differences in chewing and swallowing were not significant (P = .26 and P = .31 respectively), whereas taste was (P = .038). CONCLUSIONS: These findings suggest that reconstruction with the iliac crest had benefits in improved function (chewing, swallowing, and taste) rather than esthetics, donor site morbidity, or psychologic discomfort as was anticipated. However, prior radiation, a relatively frequent therapy in this patient population, presents an important confounding factor. Radiation therapy is difficult to control for without limiting an already scarce patient pool, and bears with it significant morbidity that likely influenced these findings. Further study is warranted to confirm the results and further distinguish the 2 groups

Horizontal maxillary osteotomy with an interpositional fibula flap for maxillary deficiency offers several advantages over conventional techniques for maxillary reconstruction. Maxillary deficiencies in all 3 planes, vertical, anterior-posterior, and transverse, can be corrected with a long-term stable construct while simultaneously restoring bony and soft tissue deficiencies. We conducted a retrospective review of patients with maxillary hypoplasia who underwent Horizontal maxillary osteotomy with interpositional osteoseptocutaneous fibula flaps. Compared with nonvascularized bone grafts, vascularized bone flaps undergo less resorption and can be used in poorly vascularized, mechanically unstable, irradiated, or scarred wound beds.

OBJECTIVES: In this retrospective review, the methods and outcomes in 96 children (98 extremities) with obstetric brachial plexus palsy who underwent primary reconstruction and/or palliative surgery for shoulder function were analysed. METHODS: Thirty cases underwent primary reconstruction alone, 37 underwent both primary and secondary procedures, and 31 late cases underwent only palliative surgery. The mean follow-up period was 6.7 years. RESULTS: The mean shoulder abduction increased from 48 degrees +/-32 degrees preoperatively to 123 degrees +/-35 degrees postoperatively (average gain 75 degrees ); the mean active external rotation with the arm at the side increased from -19 degrees +/-17 degrees to 62 degrees +/-21 degrees (mean gain 81 degrees ); and the mean aggregate Mallet score improved from 8.8 points to 20.9 points, respectively. CONCLUSIONS: Reconstruction of both axillary and suprascapular nerves yielded improved outcomes of shoulder abduction and external rotation. Early plexus reconstruction (<or=3 months) offered the best functional results and reduced the need for secondary reconstructions. A marked improvement was observed after palliative surgery irrespective of prior nerve reconstruction. Rerouting of latissimus dorsi and/or teres major tendons, combined with extra-articular musculotendinous lengthening, significantly improved global shoulder function

BACKGROUND: The viability of fat grafts obtained by even a well-established technique remains poorly studied and unknown. This study was designed to determine the viability of fat grafts harvested and refined by the Coleman technique. METHODS: Sixteen adult white women were enrolled in this study. In group 1 (n = 8), fat grafts were harvested and processed with the Coleman technique by a single surgeon from the abdomen of each patient according to his standardized method. In group 2 (n = 8), fat grafts were harvested with the conventional liposuction by another surgeon. After centrifugation, the resulting middle layer of tissue was collected. All fat graft samples were analyzed for the following studies: trypan blue vital staining for viable adipocyte counts, glycerol-3-phophatase dehydrogenase assay, and routine histologic examination. RESULTS: The higher viable adipocyte counts were found in group 1 compared with group 2 (4.11 +/- 1.11 versus 2.57 +/- 0.56 x 10 cells/ml; p < 0.004). The level of glycerol-3-phophatase dehydrogenase activity was significantly higher in group 1 compared with group 2 (0.66 +/- 0.09 versus 0.34 +/- 0.13 U/ml; p < 0.0001). Histologic examination showed normal structure of fragmented fatty tissues in both groups. CONCLUSIONS: Although fat grafts obtained by both methods maintain normal histologic structure, the Coleman technique yields a greater number of viable adipocytes and sustains a more optimal level of cellular function within fat grafts and should be considered superior to conventional liposuction as a preferred method of choice for fat graft harvesting

BACKGROUND: Although it is clear that radiation therapy can cause tissue injury, the degree of injury that is observed clinically can be highly variable. It is possible that variability in the methods by which ionizing radiation is delivered can contribute to some of the observed variability. Thus, the purpose of this study was to assess the effects of various fractionation schedules on the growth and differentiation potential of isolated mesenchymal stem cells in vitro. METHODS: Isolated mesenchymal stem cells (triplicate studies) were exposed to a dose of 12 Gy of ionizing radiation as a single dose, in two doses of 6 Gy, or in six doses of 2 Gy. Cellular proliferation and the potential for differentiation along the bone and fat lineage were assessed. Potential mechanisms for injury and protection were evaluated by analyzing the expression of p21 and manganese superoxide dismutase. RESULTS: Delivery of radiation in multiple doses confers significant radioprotection to mesenchymal stem cell proliferation and potential for differentiation. In contrast, delivery of 12 Gy of radiation as a single dose or as two equal doses of 6 Gy results in marked deficiencies in cellular proliferation and potential for multilineage cellular differentiation. CONCLUSIONS: The authors have demonstrated that even minor alterations in fractionation of radiation dose can result in significant effects on the potential of mesenchymal stem cells to differentiate. These findings imply that at least some of the variability in tissue damage after radiation therapy observed clinically may be attributable to differences in the delivery of ionizing radiation.

OBJECTIVES: Profound and growing disparities exist in oral health among certain US populations. We sought here to determine the prevalence of oral health complaints among Harlem adults by measures of social class, as well as their access to oral health care. METHODS: A population-based survey of adults in Central Harlem was conducted from 1992 to 1994. Two questions on oral health were included: whether participants had experienced problems with their teeth or gums during the past 12 months and, if so, whether they had seen a dentist. RESULTS: Of 50 health conditions queried about, problems with teeth or gums were the chief complaint among participants (30%). Those more likely to report oral health problems than other participants had annual household incomes of less than $9000 (36%), were unemployed (34%), and lacked health insurance (34%). The privately insured were almost twice as likely to have seen a dentist for oral health problems (87%) than were the uninsured (48%). CONCLUSIONS: There is an urgent need to provide oral health services for adults in Harlem. Integrating oral health into comprehensive primary care is one promising mechanism

The bony biochemical environment is an active and dynamic system that permits and promotes cellular functions that lead to matrix production and ossification. Each component is capable of conveying important regulatory cues to nearby cells, thus effecting gene expression and changes at the cytostructural level. Here, we review the various signaling molecules that contribute to the active and dynamic nature of the biochemical system. These components include hormones, cytokines, and growth factors. We describe their role in regulating bone metabolism. Certain growth factors (i.e., TGF-beta, IGF-1, and VEGF) are described in greater detail because of their potential importance in developing successful tissue-engineering strategies