Anatomic and Compression Topography of the Lesser Occipital Nerve.

BACKGROUND: The surgical treatment of occipital headaches focuses on the greater, lesser, and third occipital nerves. The lesser occipital nerve (LON) is usually transected with relatively limited available information regarding the compression topography thereof and how such knowledge may impact surgical treatment. METHODS: Eight fresh frozen cadavers were dissected focusing on the LON in relation to 3 clinically relevant compression zones. The x axis was a line drawn through the occipital protuberance (OP) and the y axis, the posterior midline (PM). In addition, a prospectively collected cohort of 36 patients who underwent decompression of the LON is presented with their clinical results, including migraine headache index scores. RESULTS: The LON was found in compression zone 1, with a mean of 7.8 cm caudal to the OP and 6.3 cm lateral to the PM. The LON was found at the midpoint of compression zone 2, with an average of 5.5 cm caudal to the OP and 6.2 cm lateral to the PM. At compression zone 3, the medial-most LON branch was located approximately 1 cm caudal to the OP and 5.35 cm lateral to the PM, whereas the lateral-most branch was identified 1 cm caudal to the OP and 6.5 cm lateral to the PM. Of the 36 decompression patients analyzed, only 5 (14%) required neurectomy as the remainder achieved statistically significant improvements in migraine headache index scores postoperatively. CONCLUSION: The knowledge of LON anatomy can aid in nerve dissection and preservation, thereby leading to successful outcomes without requiring neurectomy

Chronic Knee and Ankle Pain Treatment through Selective Microsurgical Approaches: A Minimally Invasive Option in the Treatment Algorithm for Refractory Lower Limb Pain

 Injury or compression of a sensory nerve is an under-reported source of disabling pain in the lower limb. It is known that peripheral nerve microsurgeons can reconstruct and rewire injured nerves to relieve chronic pain but this option remains not completely understood and ignored by most orthopaedic surgeons, neurologists, and pain therapists. In this paper, we describe our experience with knee and ankle peripheral nerve surgery to improve the condition of patients suffering from chronic, posttraumatic lower limb pain

Noninfectious Wound Complications in Clean Surgery: Epidemiology, Risk Factors, and Association with Antibiotic Use

Background: Noninfectious wound complications are frequent and often are confused with and treated as infection. Methods: We assessed the epidemiology, impact, risk factors, and associations with antibiotic use of noninfectious wound complications in clean orthopedic and trauma surgery. We report a single-center, prospective, observational study in an orthopedic department. Results: Among 1,073 adult patients, 630 (59%) revealed clinically relevant postoperative noninfectious wound complications, leading to a significant prolongation of hospital stay (14 vs. 12days; Wilcoxon rank-sum test; p<0.02) compared with patients without complications. The most frequent and severe complications were discharge with dehiscence (n=437; 41%) and hematoma (n=379; 35%). Forty-seven patients (47/630; 7%) underwent reoperation for dehiscence (n=39) or hematoma (n=8). These patients made up 4.3% of the entire study population (47/1,073). In multivariate analysis, an ASA score ≥2 points, age≥60years, surgery duration for ≥90min, implant-related surgery, and poor compliance toward nurses' recommendations were pronounced risk factors for these complications, whereas antibiotic-related parameters had no influence. Staple use was significantly associated with wound discharge but not with hematoma. Conclusions: Wound complications, such as dehiscence with discharge or hematoma after clean orthopedic and trauma surgery, are frequent with an overall incidence of 60%. Although they lead to few surgical reinterventions, they prolong hospital stay by 2days. Few clinical parameters show association with wound complications. Among them, improvements of patient compliance and avoidance of staples use for skin closure are the most promising actions to decrease complication ris

Use of the parabiotic model in studies of cutaneous wound healing to define the participation of circulating cells

Previous experimental studies to assess the contribution of blood-borne circulating (BBC) cells to cutaneous wound healing have relied on discontinuous pulsing of labeled BBC elements or bone marrow transplant protocols. Such approaches do not allow the examination of stable BBC cells that have matured in a physiologically normal host. We have used a parabiotic murine model for cutaneous wound healing to evaluate the relative contribution of stable populations of peripheral blood cells expressing the green fluorescent protein (GFP) transgene in otherwise normal animals. Circulating cells (mature and immature) expressing the GFP transgene were easily detected and quantified in wounds of GFP− parabiotic twins during all evaluated stages of the healing response. Using multiple antibody probes, the relative contribution of various subsets of BBC cells could be comparatively assessed. In early wounds, some cells expressing mesenchymal epitopes were documented to be of hematopoietic origin, indicating the utility of this model in assessing cell plasticity in the context of tissue regeneration and repair. Application of this approach enables further investigation into the contribution of peripheral blood in normal and abnormal healing responses.National Institutes of Health (U.S.) (NIH 5 T32 HL007627- 22 Physician-Scientist Training Grant)National Institutes of Health (U.S.) (NIH/NIDDK (5 P30 DK36836-20))Brigham and Women’s Hospital (Program in Dermatopathology core grant (SDRC))National Institutes of Health. (U.S.). Department of Health and Human Services (Brigham and Women’s Hospital’s Program in Dermatopathology core grant (SPORE)

Anti-Bacterial Effects of Poly-N-Acetyl-Glucosamine Nanofibers in Cutaneous Wound Healing: Requirement for Akt1

Treatment of cutaneous wounds with poly-N-acetyl-glucosamine nanofibers (sNAG) results in increased kinetics of wound closure in diabetic animal models, which is due in part to increased expression of several cytokines, growth factors, and innate immune activation. Defensins are also important for wound healing and anti-microbial activities. Therefore, we tested whether sNAG nanofibers induce defensin expression resulting in bacterial clearance.The role of sNAG in defensin expression was examined using immunofluoresence microscopy, pharmacological inhibition, and shRNA knockdown in vitro. The ability of sNAG treatment to induce defensin expression and bacterial clearance in WT and AKT1-/- mice was carried out using immunofluoresent microscopy and tissue gram staining. Neutralization, using an antibody directed against β-defensin 3, was utilized to determine if the antimicrobial properties of sNAG are dependent on the induction of defensin expression.sNAG treatment causes increased expression of both α- and β-type defensins in endothelial cells and β-type defensins in keratinocytes. Pharmacological inhibition and shRNA knockdown implicates Akt1 in sNAG-dependent defensin expression in vitro, an activity also shown in an in vivo wound healing model. Importantly, sNAG treatment results in increased kinetics of wound closure in wild type animals. sNAG treatment decreases bacterial infection of cutaneous wounds infected with Staphylococcus aureus in wild type control animals but not in similarly treated Akt1 null animals. Furthermore, sNAG treatment of S. aureus infected wounds show an increased expression of β-defensin 3 which is required for sNAG-dependent bacterial clearance. Our findings suggest that Akt1 is involved in the regulation of defensin expression and the innate immune response important for bacterial clearance. Moreover, these findings support the use of sNAG nanofibers as a novel method for enhancing wound closure while simultaneously decreasing wound infection

Poly-N-Acetyl Glucosamine Fibers Induce Angiogenesis in ADP Inhibitor-Treated Diabetic Mice

Background: It has been previously demonstrated that short-fiber poly-N-acetyl-glucosamine (sNAG) nanofibers specifically interact with platelets, are hemostatic, and stimulate diabetic wound healing by activating angiogenesis, cell proliferation, and reepithelialization. Platelets play a significant physiologic role in wound healing. The influence of altered platelet function by treatment with the ADP inhibitor Clopidogrel (CL) on wound healing and the ability of sNAG to repair wounds in diabetic mice treated with CL were studied.Methods: Dorsal 1 cm2 skin wounds were excised on genetically diabetic 8-week to 12-week-old, Lep/r-db/db male mice, and wound healing kinetics were determined. Microscopic analysis was performed for angiogenesis (PECAM-1) and cell proliferation (Ki67). Mice were either treated with CL (P2Y12 ADP receptor antagonist, CL) or saline solution (NT). CL wounds were also treated with either a single application of topical sNAG (CL-sNAG) or were left untreated (CL-NT).Results: CL treatment did not alter wound healing kinetics, while sNAG induced faster wound closure in CL-treated mice compared with controls. CL treatment of diabetic mice caused an augmentation of cell proliferation and reduced angiogenesis compared with nontreated wounds. However, sNAG reversed the effects of CL on angiogenesis and partially reversed the effect on cell proliferation in the wound beds. The sNAG-treated wounds in CL-treated mice showed higher levels of cell proliferation and not did inhibit angiogenesis.Conclusions: CL treatment of diabetic mice decreased angiogenesis and increased cell proliferation in wounds but did not influence macroscopic wound healing kinetics. sNAG treatment did not inhibit angiogenesis in CL-treated mice and induced faster wound closure; sNAG technology is a promising strategy to facilitate the healing of complex bleeding wounds in CL-treated diabetic patients