Faculty Bibliography

BACKGROUND:Occipital neuralgia (ON) is a primary headache disorder characterized by severe, paroxysmal, shooting or stabbing pain in the distribution of the greater occipital, lesser occipital, and/or third occipital nerves. Both medical and surgical options exist for treating headaches related to ON. The purposes of this study are to summarize the current state of surgical ON management through a systematic review of the literature and, in doing so, objectively identify future directions of investigation. METHODS:We performed a systematic review of primary literature on surgical management for ON of at least level IV evidence. Included studies were analyzed for level of evidence, therapeutic intervention, study design, sample size, follow-up duration, outcomes measured, results, and risk of bias. RESULTS:Twenty-two studies met the inclusion criteria. All 22 studies used patient-reported pain scores as an outcome metric. Other outcome metrics included complication rates (7 studies; 32%), patient satisfaction (7 studies; 32%), quality of life (7 studies; 18%), and analgesic usage (3 studies; 14%). Using the ROBINS-I tool for risk of bias in nonrandomized studies, 7 studies (32%) were found to be at critical risk of bias, whereas the remaining 15 studies (68%) were found to be at serious risk of bias. CONCLUSIONS:Greater occipital nerve decompression seems to be a useful treatment modality for medically refractory ON, but further prospective, randomized data are required.

Multisystem inflammatory syndrome in children (MIS-C) is thought to follow SARS-CoV-2 infection and presents with fever and multisystem dysfunction. We report three children with suspected MIS-C found to have retropharyngeal edema without evidence of a bacterial etiology. We raise the possibility that an association between MIS-C and retropharyngeal edema exists.

The forkhead box O1 (FOXO1) transcription factor plays a key role in wound healing process. Recently it has been reported that lineage-specific genetic ablation of FOXO1 significantly improves diabetic wound healing in a mouse model. To investigate the clinical usefulness of these findings, translational preclinical studies with a large animal model are needed. We report for the first time that the local application of a FOXO1 inhibitor (AS1842856) significantly improves connective tissue healing in a preclinical T2DM minipig model, reflected by increased collagen matrix formation, increased myofibroblast numbers, improved angiogenesis, and a shift in cell populations from pro-inflammatory (IL-1β⁺, TNF-α⁺ and iNOS⁺) to pro-healing (CD163⁺). Our results set up the basis for the clinical application of a FOXO1 antagonist in early diabetic wounds where there is impaired connective tissue healing.

PURPOSE/OBJECTIVE:The aim of this work was to evaluate osseointegration of endosteal implants with two different surface treatments at early stages (~3 weeks) in the tibia of healthy and ovariectomized rabbits. MATERIALS AND METHODS/METHODS:The study comprised 10 adult New Zealand female rabbits (Oryctolagus cuniculus; 6 months and 3.0 ± 0.5 kg). Five animals were subjected to bilateral ovariectomy to mimic osteoporotic-like conditions, and the remaining rabbits (n = 5) served as the healthy control group. After 3 months, specimens from the ovariectomized and control groups were subject to implant placement in both tibiae, using two different types of surface treatment. A total of 36 implants were placed, n = 18 acid-etched and n = 18 anodized. After 3 weeks, euthanasia of the animals was performed, and samples were obtained for processing. Bone-to-implant contact and bone area fraction occupancy were quantified to evaluate the osseointegration parameters around the implant surface and within the thread area, respectively, and nanoindentation tests were performed to determine elastic modulus and hardness of the new bone. Both analyses were performed on the entire implant (total), as well as individually within the cortical and bone marrow cavity area. RESULTS:All animals were evaluated with no signs of infection or postoperative complications. The total bone-to-implant contact and bone area fraction occupancy results, independent of surface treatment, yielded significant differences between the ovariectomized and control groups (P = .002 and P < .001, respectively). In the marrow cavity, analyzing the surface treatments independently as a function of bone condition, the only differences detected were in the anodized treatment (P = .04). Regarding the elastic modulus, differences were detected only with the anodized implants between the ovariectomized and control groups (P = .015). CONCLUSION/CONCLUSIONS:At 3 weeks after implant placement, there were better osseointegration values of the implants in the healthy control group compared with the ovariectomized group independent of surface treatment. Also, specifically in the medullary region of the rabbit tibia, the acid-etched implants had more uniform osseointegration values in conditions of low-quality bone in comparison to the anodized implants, histomorphometrically and biomechanically.

ABSTRACT/UNASSIGNED:Migraine affects ∼15% of the world's population greatly diminishing their quality of life. Current preventative treatments are effective in only a subset of migraine patients, and while cannabinoids appear beneficial in alleviating migraine symptoms, central nervous system (CNS) side effects limit their widespread use. We developed peripherally-restricted cannabinoids (PRCBs) that relieve chronic pain symptoms of cancer and neuropathies, without appreciable CNS side effects or tolerance development. Here we determined PRCB effectiveness in alleviating hypersensitivity symptoms in mouse models of migraine and medication overuse headache (MOH). Chronic glyceryl trinitrate (GTN, 10 mg/kg) administration led to increased sensitivity to mechanical stimuli, and increased expression of phosphorylated protein kinase A (p-PKA), neuronal nitric oxide synthase (nNOS), and transient receptor potential ankyrin 1 (TRPA1) proteins in trigeminal ganglia. PRCB pretreatment, but not posttreatment, prevented behavioral and biochemical correlates of GTN-induced sensitization. Low pH- and allyl isothiocyanate-activated currents in acutely isolated trigeminal neurons were reversibly attenuated by PRCB application. Chronic GTN treatment significantly enhanced these currents. Chronic sumatriptan treatment also led to development of allodynia to mechanical and cold stimuli which was slowly reversible after sumatriptan discontinuation. Subsequent challenge with a previously ineffective low-dose GTN (0.1-0.3 mg/kg) revealed latent behavioral sensitization and increased expression of p-PKA, nNOS, and TRPA1 proteins in trigeminal ganglia. PRCB pretreatment prevented all behavioral and biochemical correlates of allodynia and latent sensitization. Importantly, chronic PRCB treatment alone did not produce any behavioral or biochemical signs of sensitization. These data validate peripheral cannabinoid receptors as potential therapeutic targets in migraine and MOH.

OBJECTIVE/UNASSIGNED:This study evaluates skeletal and dental outcomes of LeFort I advancement surgery in patients with cleft lip and palate (CLP) with varying degrees of maxillary skeletal hypoplasia. DESIGN/UNASSIGNED:Retrospective study. METHOD/UNASSIGNED:: ≤-10 mm. PARTICIPANTS/UNASSIGNED:Fifty-one patients with nonsyndromic CLP with hypoplastic maxilla who met inclusion criteria. INTERVENTION/UNASSIGNED:LeFort I advancement. MAIN OUTCOME MEASURE/UNASSIGNED:Skeletal and dental stability post-LeFort I surgery at a 1-year follow-up. RESULTS/UNASSIGNED:At T2, LeFort I surgery produced an average correction of maxillary hypoplasia by 6.4 ± 0.6, 8.1 ± 0.4, and 10.7 ± 0.8 mm in the mild, moderate, and severe groups, respectively. There was a mean relapse of 1 to 1.5 mm observed in all groups. At T3, no statistically significant differences were observed between the surgical groups and controls at angle Sella, Nasion, A point (SNA), A point, Nasion, B point (ANB), and overjet outcome measures. CONCLUSIONS/UNASSIGNED:LeFort I advancement produces a stable correction in mild, moderate, and severe skeletal maxillary hypoplasia. Overcorrection is recommended in all patients with CLP to compensate for the expected postsurgical skeletal relapse.

OBJECTIVE:To evaluate the fatigue survival, failure mode, and maximum principal stress (MP Stress) and strain (MP Strain) of resin-matrix ceramic systems used for implant-supported crowns. METHODS:Identical molar crowns were milled using four resin-matrix ceramics (n = 21/material): (i) Shofu Hard, (ii) Cerasmart (iii) Enamic, and (iv) Shofu HC. Crowns were cemented on the abutments, and the assembly underwent step-stress accelerated-life testing. Use level probability Weibull curves at 300 N were plotted and the reliability at 300, 500 and 800 N was calculated for a mission of 50,000 cycles. Fractographic analysis was performed using stereomicroscope and scanning electron microscope. MP Stress and MP Strain were determined by finite element analysis. RESULTS:While fatigue dictated failures for Cerasmart (β > 1), material strength controlled Shofu Hard, Enamic, and Shofu HC failures (β < 1). Shofu HC presented lower reliability at 300 N (79%) and 500 N (59%) than other systems (>90%), statistically different at 500 N. Enamic (57%) exhibited a significant reduction in the probability of survival at 800 N, significantly lower than Shofu Hard and Cerasmart; however, higher than Shofu HC (12%). Shofu Hard and Cerasmart (>93%) demonstrated no significant difference for any calculated mission (300-800 N). Failure mode predominantly involved resin-matrix ceramic fracture originated from occlusal cracks, corroborating with the MP Stress and Strain location, propagating through the proximal and cervical margins. SIGNIFICANCE/CONCLUSIONS:All resin-matrix ceramics crowns demonstrated high probability of survival in a physiological molar load, whereas Shofu Hard and Cerasmart outperformed Enamic and Shofu HC at higher loads. Material fracture comprised the main failure mode.

Marko Godina in his landmark paper in 1986 established the principle of early flap coverage for reconstruction of traumatic lower extremity injuries to minimize edema, fibrosis, and infection while optimizing outcomes. However, with the evolution of microsurgery and wound management, there is emerging evidence that timing of reconstruction is not as critical as once believed. Multidisciplinary care with a combined orthopedic and reconstructive approach is more critical for timely and appropriate definite treatment for severe lower extremity injuries.

SUMMARY/CONCLUSIONS:Prepectoral breast reconstruction has minimized morbidity and dynamic deformities associated with submuscular implant-based breast reconstruction. However, reliance on implant coverage with acellular dermal matrix in immediate implant reconstruction remains limited by high material costs. The authors describe a technique in which anterior implant coverage in prepectoral reconstruction is split into acellular dermal matrix inferolaterally and synthetic, absorbable mesh superiorly. Use of acellular dermal matrix inferiorly provides coverage and reinforces the inframammary fold, whereas the absorbable mesh is trimmed and sutured to the acellular dermal matrix at the appropriate tension to support the implant and relieve pressure on mastectomy flaps. A retrospective review was performed on all consecutive prepectoral one-stage breast reconstructions using this technique at a single institution. Patient demographics, mastectomy and reconstruction characteristics, reconstructive outcomes, and cost of support materials were queried and analyzed. Eleven patients (21 breasts) underwent prepectoral immediate implant reconstruction with Vicryl and acellular dermal matrix anterior coverage. Average mastectomy weight was 775.8 g. Smooth, round cohesive implants were used in all cases and average implant size was 514.5 ml. Overall complication rates were low and included one minor infection (4.8 percent) and one case of minor mastectomy flap and partial nipple necrosis each (4.8 percent). Calculated cost savings of Vicryl and acellular dermal matrix anterior coverage was up to $3415 in unilateral and $6830 in bilateral cases. Prepectoral breast reconstruction using acellular dermal matrix inferiorly and Vicryl mesh superiorly is a safe technique that decreases material costs associated with support materials and allows the surgeon to precisely control the implant pocket and position. CLINICAL QUESTION/LEVEL OF EVIDENCE/METHODS:Therapeutic, IV.