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Dive into the research topics where Jeffrey C. Posnick is active.

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Featured researches published by Jeffrey C. Posnick.


Plastic and Reconstructive Surgery | 2011

Long-term outcomes of primary craniofacial reconstruction for craniosynostosis: a 12-year experience.

Mitchel Seruya; Albert K. Oh; Michael J. Boyajian; Jeffrey C. Posnick; John S. Myseros; Amanda L. Yaun; Robert F. Keating

Background: The purpose of this study was to critically assess long-term outcomes after open reconstruction of craniosynostosis within the recent decade. Methods: The authors performed a retrospective, institutional review board–approved review of open repair for craniosynostosis between 1997 and 2009. Surgical factors, complications, and long-term outcomes were assessed. Pearson chi-square, Fishers exact, and Kaplan-Meier analyses were performed. Results: Of 212 patients, 72 underwent primary extended synostectomy and 140 had traditional open craniofacial repair. Mean follow-up was 36.3 months (range, 0.5 to 138 months). Indications included sagittal (n = 96), metopic (n = 40), unicoronal (n = 33), bicoronal (n = 24), multisutural (n = 15), bilambdoidal (n = 3), and unilambdoidal (n = 1) synostoses; 8.5 percent of patients were syndromic. Surgical reconstruction was performed at a mean age of 11.3 months (range, 0.2 to 117.8 months), including nonsyndromic patients at an average age of 10.6 months and syndromic patients at age 19.3 months. There were no deaths. A 3.3 percent complication rate included two cerebral contusions, two hematomas, one cerebrospinal fluid leak, one infection, and one wound breakdown. Patients were categorized as 89.2 percent Whitaker class I/II and 10.8 percent Whitaker class III/IV. Major and total reoperation rates were 9.0 percent and 10.8 percent, respectively. Higher total reoperation rate and Whitaker class III/IV distribution significantly correlated with syndromic diagnosis, bicoronal synostosis, and surgical age younger than 6 months. Conclusions: In this experience of contemporary open craniosynostosis surgery, rates of morbidity, mortality, and reoperation were low. These results support the merits of surgical delay, targeting an age of 6 months or older, and may serve as a more accurate metric of comparison to current minimally invasive techniques for craniosynostosis repair.


Journal of Oral and Maxillofacial Surgery | 1992

Modification of the maxillary Le Fort I osteotomy in cleft-orthognathic surgery: The unilateral cleft lip and palate deformity

Jeffrey C. Posnick; Bryan Tompson

The adolescent with bilateral cleft lip and palate (BCLP) undergoing orthognathic surgery may have multiple residual clefting problems, including a mobile, dysplastic premaxilla and hypoplastic lateral maxillary segments, with each segment misaligned in three dimensions. These problems are commonly compounded by residual oronasal fistulas, bony defects, soft-tissue scarring from previous surgery, and the congenital absence of the maxillary lateral incisor teeth with resulting cleft-dental gaps. This article describes modifications of the Le Fort I osteotomy that allow for the simultaneous routine and safe management of these deformities. Results of this operation on 22 consecutive patients are reported, with findings of follow-up ranging from 1 to 5 years. The long-term parameters reviewed include closure of residual oronasal fistulas, stabilization of the premaxilla, cleft-dental gap closure, maintenance of attached gingiva at the cleft site, maintenance of a positive overjet and overbite, the need for prosthetics to complete dental rehabilitation, and surgical morbidity.


Neurosurgery | 1993

Reconstruction of skull defects in children and adolescents by the use of fixed cranial bone grafts: long-term results.

Jeffrey C. Posnick; Jeffrey A. Goldstein; Derek Armstrong; James T. Rutka

This article presents the long-term results of skull defect reconstruction in a series of 27 children studied between 1986 and 1990 (mean age, 8.4 yr; range, 1-17 yr). Causes of their defects were encephalocele (six patients), trauma (seven patients), tumor (eight patients), fibrous dysplasia (two patients), postsynostectomy defects (two patients), osteomyelitis (one patient), and Reyes syndrome with bone flap loss (one patient). All patients underwent clinical and computed tomographic scan documentation of their skull defects before and immediately after surgery and at least 1 year later. The average preoperative defect surface area measured 33 cm2 (range, 2.5-114 cm2). Skull defects were reconstructed in all patients with fixed autogenous cranial bone grafts. In the initial five patients, the grafts were fixed with interosseous wires, and in the remainder, they were fixed with a combination of miniplates and microplates and screws. Follow-up ranged from 12 to 66 months (mean, 31.4 mo). Complications were minimal, with no infection, plate or graft exposure, or intracranial injuries. In 24 of 27 patients, clinical examination and computed tomographic scans showed no evidence of skull defect or appreciable irregularity of donor or recipient sites. Two patients had documented small regions of graft resorption. One skull had palpable contour irregularities but without a bony defect. All patients have resumed routine activities and sports without special head protection. Repair of skull defects in children with fixed autogenous cranial grafts is a reliable method of reconstruction with minimal morbidity. Although we prefer miniplates and microplates and screws for fixation, the grafts fixed in place with interosseous wires did equally well.


Neurosurgery | 1993

Reconstruction of Skull Defects in Children and Adolescents by the Use of Fixed Cranial Bone Grafts

Jeffrey C. Posnick; Jeffrey A. Goldstein; Derek Armstrong; James T. Rutka

This article presents the long-term results of skull defect reconstruction in a series of 27 children studied between 1986 and 1990 (mean age, 8.4 yr; range, 1-17 yr). Causes of their defects were encephalocele (six patients), trauma (seven patients), tumor (eight patients), fibrous dysplasia (two patients), postsynostectomy defects (two patients), osteomyelitis (one patient), and Reyes syndrome with bone flap loss (one patient). All patients underwent clinical and computed tomographic scan documentation of their skull defects before and immediately after surgery and at least 1 year later. The average preoperative defect surface area measured 33 cm2 (range, 2.5-114 cm2). Skull defects were reconstructed in all patients with fixed autogenous cranial bone grafts. In the initial five patients, the grafts were fixed with interosseous wires, and in the remainder, they were fixed with a combination of miniplates and microplates and screws. Follow-up ranged from 12 to 66 months (mean, 31.4 mo). Complications were minimal, with no infection, plate or graft exposure, or intracranial injuries. In 24 of 27 patients, clinical examination and computed tomographic scans showed no evidence of skull defect or appreciable irregularity of donor or recipient sites. Two patients had documented small regions of graft resorption. One skull had palpable contour irregularities but without a bony defect. All patients have resumed routine activities and sports without special head protection. Repair of skull defects in children with fixed autogenous cranial grafts is a reliable method of reconstruction with minimal morbidity. Although we prefer miniplates and microplates and screws for fixation, the grafts fixed in place with interosseous wires did equally well.


Pediatric Neurosurgery | 1993

Childhood fibrous dysplasia presenting as blindness: a skull base approach for resection and immediate reconstruction

Jeffrey C. Posnick; Mark D. Wells; James M. Drake; Raymond Buncic; Derek Armstrong

Fibrous dysplasia is an abnormal fibroosseous process of bone of unknown cause. The incidence of skull involvement varies, painless enlargement being the most common presenting symptom. Change in vision is a rare but recognized finding. We report a 3-year-old boy with extreme fibrous dysplasia involving the skull base, who presented with blindness. He underwent exposure osteotomies of the frontal bones and orbits to provide access for skull base tumor removal. The orbital roofs were reconstructed with microplate-fixed cranial grafts. One and one half years after tumor excision followed by immediate reconstruction, the boy retains facial symmetry, and his ocular function has not deteriorated.


Plastic and Reconstructive Surgery | 1993

Fetal tibial bone healing in utero : the effects of miniplate fixation

Slate Rk; Jeffrey C. Posnick; Wells; Jeffrey A. Goldstein; Keeley Fw; Thorner Ps

Although clinical and experimental findings have demonstrated that fetal soft-tissue wounds heal without scarring, very little is known about the process of fetal bone healing. This study examined fetal long bone healing in utero, both histologically and biochemically, with and without fracture fixation in a fetal sheep model. Our study group consisted of 25 live fetuses (from 16 ewes). There were 50 fetal tibias in this group; 12 were control, 17 were fixed (miniplate fixation), and 21 were nonfixed. A midshaft osteotomy of the tibia, either fixed or non-fixed, was performed on fetal sheep at 95 days gestation (term = 145 days) in utero. The sheep were then killed at one of five postoperative time intervals (weeks 1, 2, 3, 4, and 7), and fetal bone healing was examined. The variables reviewed included gross morphology, histology, radiology, and collagen analysis (proportions of types II to I and III to I collagen). Fetal bone healing without fixation was accompanied by a large callus with rapid and abundant cartilage and collagen deposition. Bone healing was characterized by malunion or nonunion at 7 weeks. However, with miniplate and screw fixation, callus formation was minimal; primary bone healing occurred by 3 weeks and did not adversely affect long bone growth. Analysis of callus samples revealed a minimal amount of type III collagen, whereas the proportion of type II collagen was variable and proportional to the content of callus cartilage.


Journal of Craniofacial Surgery | 1996

Monobloc and facial bipartition osteotomies: a step-by-step description of the surgical technique.

Jeffrey C. Posnick

The surgical management of upper and midface deformities in the craniofacial dysostosis syndromes has evolved gradually. Staged surgical procedures performed at intervals to coincide with facial growth, visceral function, and psychosocial development represent the current approach. The lack of consensus on timing and techniques for the management of the complex upper and midface deformities reflects not only uncertainty about the results achieved with any one approach to treatment but also confusion about how to perform the intricate and technically sensitive procedures. The purpose of this article is to provide the surgeon with a step-by-step technical description of the monobloc and facial bipartition osteotomies as I routinely perform them. By understanding the details for their safe execution, craniofacial surgeons are able to maintain these reconstructive options as active components in their armamentarium.


Journal of Neurosurgery | 2011

Treatment for delayed presentation of sagittal synostosis: challenges pertaining to occult intracranial hypertension

Mitchel Seruya; Albert K. Oh; Michael J. Boyajian; Jeffrey C. Posnick; Robert F. Keating

OBJECTnPatients with delayed presentation of isolated sagittal synostosis (ISS) pose unique surgical challenges. Intracranial hypertension can be missed in the absence of overt findings. Here, an algorithm is presented for the elucidation of intracranial hypertension and approaches to surgical treatment during calvarial reconstruction.nnnMETHODSnPatients with delayed presentation (age > 15 months) of ISS between 1997 and 2009 were identified. Symptoms, signs, and radiological evidence of intracranial hypertension were noted. Intraoperative management included calvarial reconstruction in conjunction with ventriculostomy for intracranial pressure (ICP) monitoring and CSF drainage in the setting of suspected intracranial hypertension.nnnRESULTSnSeventeen patients underwent calvarial reconstruction for delayed presentation of ISS. The mean surgical age was 40.5 months (16.2-82.9 months), and the average follow-up was 34.2 months (0.6-92.2 months). Eleven patients with subtle findings of intracranial hypertension underwent ICP monitoring during calvarial reconstruction. The mean opening ICP was 23.5 cm H(2)O (16.5-29.5 cm H(2)O), and the mean closing ICP was 7.0 cm H(2)O (3.5-17.0 cm H(2)O). Nine (81.8%) of 11 monitored patients demonstrated intracranial hypertension (ICP ≥ 20 cm H(2)O); the other 2 had borderline increased ICP. Perioperative morbidity was 5.9%, with 1 patient medically treated for transient, new-onset intracranial hypertension. The postoperative Whitaker category was I in 94.1% of patients, II in 5.9%, and III/IV in 0%. There were no reoperations or deaths.nnnCONCLUSIONSnIn this consecutive series, 11 of 17 patients with delayed presentation of ISS underwent ICP monitoring during calvarial reconstruction as a result of subtle clinical findings of intracranial hypertension. Nine (81.8%) of 11 monitored patients demonstrated intracranial hypertension. Calvarial reshaping along with ICP monitoring and CSF drainage facilitated reconstruction and resulted in good outcomes and the resolution of intracranial hypertension.


Plastic and Reconstructive Surgery | 1994

An assessment of postnatal growth after in utero long bone osteotomy with fixation

Jeffrey A. Goldstein; Jeffrey C. Posnick; Wells; Slate Rk; Thorner Ps

Researchers have recently suggested that rigid fixation of the immature bony skeleton may restrict growth and development. This study assesses the effect on postnatal growth of an in utero tibial osteotomy fixed with a miniplate in fetal sheep. A midshaft osteotomy was performed on fetal sheep tibia (n = 5) at 95 days gestation (term 145 days). One tibia was reduced and fixed with a titanium miniplate and screws, while the contralateral hindlimb served as a control. The newborns were vaginally delivered and sacrificed at 2 months of age. The hindlimbs, control and fractured, were harvested, stripped of soft tissue, and the tibia, femur, and distal metatarsal were each measured and weighed. Each tibia also underwent radiographic analysis and histologic examination (after decalcification) using hematoxylin and eosin, Sirius red, and Alcian blue stains. No prenatal, postnatal, or perioperative medical complications occurred. Apart from a slight angulation in one operated tibia, no gross morphologic differences, either visible or palpable, were found between the operated and control limbs. This was confirmed radiographically where no remnant of the osteotomy site was visible. Measurements of the operated and control tibias, femurs, and metatarsal bones were not statistically different. Histologic analysis showed a total incorporation of bone at the osteotomy site with appositional growth present. All bone was lamellar with longitudinal orientation. In the area of the screw sites, the surrounding bone shaft was the same width as its neighboring bone. Epiphyses also appeared normal. In utero long bone healing of a midshaft tibial osteotomy (nongrowth center) with miniplate fixation does not appear to retard postnatal growth.


Plastic and Reconstructive Surgery | 1990

A method for repositioning the external ear

Linton A. Whitaker; Michael J. Yaremchuk; Jeffrey C. Posnick

The malposition of an otherwise normal-appearing external ear is not uncommon in certain craniofacial syndromes. This paper presents a 10-year experience of 14 patients who underwent external ear repositioning. In this technique, a posterior incision is used to mobilize surrounding soft tissues circumferentially around the external auditory canal, which then serves as an axis for anterior rotation and elevation. Elevation of up to 8 mm and rotation up to 30 degrees can be achieved. Further elevation is limited by the ensuing constriction and resistance of the external auditory canal. More rotation can be achieved with a Z-plasty transposition of an inferiorly based postauricular skin flap.

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Albert K. Oh

Children's National Medical Center

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Michael J. Boyajian

Children's National Medical Center

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Mitchel Seruya

Children's Hospital Los Angeles

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Robert F. Keating

Children's National Medical Center

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Amanda L. Yaun

Children's National Medical Center

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