Anterior Border Research Articles

Vitreopapillary Tractions

Vitreo-papillary tractions develop in the posterior vitreous detachment (PVD) development process that vitreous cannot pass the separation process from the papilla. Distortion of the nerve fiber layer and microvascular structures in the papillae by the posterior hyaloid traction causes deterioration of visual functions. Conditions causing local ocular anatomic variations, such as small crowded papillae, previous trauma, intraocular surgery, intraocular inflammations, intraocular vascular problems may be predisposing for abnormal PVD. Vitreopapillary tractions (VPT) can be classified as primary if there is no other ocular pathology that can lead to abnormal PVD, and secondary, if there is a concurrent pathology that can lead to abnormal PVD. Three types of VPT's are defined according to the Optical coherence tomography (OCT) based classification. Type 1: vitreous band traction on the optic disc Type 2: prominent vitreous condensation at the optic disc surface and cup, Type 3: elevation of the anterior optic disc cup border above the level of the retina pigment epithelium/Bruch's membrane. Diagnosis is made by clinical examination ultrasonography and OCT findings. Vitrectomy is performed in situations that threaten visual functions in the treatment.

Clinical Significance of Lateral Ankle Radiograph after the Reduction of a Syndesmosis Injury

Category: Trauma Introduction/Purpose: To introduce reliable and newly developed radiographic measures based on a lateral ankle radiograph to assess a syndesmotic reduction after screw fixation and to compare with the radiographic measures based on the anteroposterior (AP) and mortise radiographs. Methods: The postoperative ankle radiographs of 34 ankle fracture cases after screw fixation for concurrent syndesmosis injury were reviewed. Two radiographic parameters were measured on each AP and mortise radiograph; tibiofibular clear space (TFCS) and tibiofibular overlap (TFO). Five radiographic parameters were measured on the true lateral radiographs; the anteroposterior tibiofibular (APTF) ratio, anterior tibiofibular ratio (ATFR), posterior tibiofibular ratio (PTFR), distances of intersection of the anterior fibular border and the tibial plafond to anterior cortex of the tibia (AA’), and the intersection of posterior fibular border and tibial plafond to the tip of the posterior malleolus (BB’). In addition, the distance (XP) between the fibular posterior margin (X) crossing tibial plafond or the posterior malleolus and posterior articular margin (P) of the tibial plafond was measured on the lateral view. Results: Using TFCS and TFO in the AP and mortise radiographs, malreductions of syndesmosis were estimated in 17 of 34 cases (50.0%). Using the introduced and developed radiographic measures in the lateral radiographs, syndesmotic malreductions were estimated in 16 out of 34 cases (47.1%). Seventeen cases (50.0%) showed no evidence of postoperative diastasis using the radiographic criteria on the AP and mortise view, 10 cases (58.8%) of whom showed evidence of a malreduction on the lateral radiograph. The newly developed measurements, XP, were measured 0 in 11 out of 34 cases (32.4%). Conclusion: The reduction of syndemosis after screw fixation can be accurately assessed intraoperatively with a combination of several reliable radiographic measurements of lateral radiograph and traditional radiographic measurements of AP and mortise radiograph. Using various radiographic parameters selectively, malreduction could be prevented even when some parameters are difficult to measure because of implants or when posterior malleolar fracture is accompanied.

Effect of percutaneous kyphoplasty on the quality of life in patients with osteoporotic vertebral compression fractures

Objective To study the effect of percutaneous kyphoplasty(PKP) in the treatment of patients with osteoporotic vertebral compression fractures(OVCF), and its influence on the quality of life of patients. Methods 100 cases with OVCF from January 2014 to January 2016 in Department of orthopedics, Shangyu District People's Hospital of Shaoxing city were selected as the research subjects.According to random number table method, the patients were divided into control group and observation group, with 50 cases in each group.The control group was treated by percutaneous vertebroplasty(PVP), the observation group was treated by PKP.The anterior vertebral height and kyphosis Cobb angle, the degree of pain, limb dysfunction, and quality of life score were compared between the two groups. Results After operation, the scores of VAS and ODI in the observation group were (2.27±1.25)points and (27.17±7.35)points, respectively, which were lower than those in the control group [(3.52±1.57)points, (44.28±8.63)points](t=4.404, 9.913, all P<0.05). After operation, the height of the anterior border of the observation group was (19.87±1.33)mm, which was higher than (19.22±1.30)mm of the control group, and the kyphosis Cobb angle of the observation group was (5.31±2.12)°, which was less than (6.34±2.78)°of the control group (t=2.471, 2.083, all P<0.05). After operation, the score of quality of life in the observation group was (78.69±13.77), which was higher than (65.46±12.67) in the control group (t=2.471, 2.083, all P<0.05). Conclusion The curative effect of PKP in the treatment of OVCF is positive, it can restore vertebral height, correct kyphosis, relieve pain, improve limb function of patients, and improve the quality of life of patients, it is worthy of clinical application. Key words: Osteoporotic fractures; Fractures, compression; Vertebroplasty; Quality of life

Polypoid change of middle turbinate is associated to an increased risk of polyp recurrence after surgery in patients with chronic rhinosinusitis with nasal polyps.

Chronic rhinosinusitis with nasal polyps (CRSwNP) affects approximately 4% of general population. Patients with CRSwNP have greater burden of CRS symptoms and higher rate of relapse after either medical or surgical treatments. The aim of this study was to evaluate the association between polypoid change of anterior free border of middle turbinate and rate of relapse in patients with CRSwNP. A controlled prospective cohort study was performed. Seventy-seven adult patients with CRSwNP in whom their MT polypoid change was proved and 77 patients without MT polypoid change were recruited. Allergy, asthma, aspirin hypersensitivity, Lund Kennedy and Lund Mackay scores and eosinophilic scores of polyp and middle turbinate were recorded. Patient's health-related quality of life was assessed using the 22-item Sino-Nasal Outcome Test (SNOT-22) questionnaire. All patients were evaluated 12 months after ESS. Polyp relapse, Lund Kennedy scores and SNOT-22 scores were documented. The relapse rate in patients with MT polypoid change was significantly higher than the control group (37.14 vs. 20.58, p value = 0.03). Eosinophil score of nasal polyps and MT specimens were significantly higher in patients with MT polypoid change than patients without polypoid change. The postoperative Lund Kennedy and SNOT-22 scores in patients with MT polypoid change were significantly higher than the control group. This study showed a significant association between polypoid change of anterior free border of middle turbinate and nasal polyp relapse. This new and simple criterion of severity of CRSwNP could have clinical implications.

Optimization of cervical lymph node clinical target volume delineation in nasopharyngeal carcinoma: a single center experience and recommendation.

Nasopharyngeal carcinoma (NPC) are characterized by distinct lymph node metastasis patterns. In order to minimize cervical lymph node irradiation volume, 379 NPC patients with metastatic cervical lymph nodes were eligible for geographic mapping. All lymph nodes were mapped into simulation computed tomography images of a template lymph node negative patient. The proportions of retropharyngeal lymph nodes (RLNs), Level Ib, II, III, IV, Va, Vb and supraclavicular (SCV) lymph nodes were 6.9%, 0.5%, 55.25%, 20.4%, 8.2%, 4.9%, 3.1% and 0.75%, respectively. Based on their distribution profile, we proposed the following modifications: 1. the lateral border of RLNs clinical target volume (CTV) be the medial edge of the internal carotid artery above the level of mastoid process, the medial border be adjacent to the cervical vessels below the free edge of the soft palate; 2. the submandibular gland should not be included in Level Ib; 3. Level II should include the posterior belly of digastric muscle, and the space between the posterior edge of submandibular gland and the anterior edge of sternocleidomastoid muscle; 4. the anterior border of Level III and IV should gradually shift backwards and the CTV only include part of the cervical vessels below the level where the thyroid gland appears; 5. the space of the posterior edge of trapezius muscle also should be included if there are metastatic lymph nodes in the transverse cervical vessle plexus. Our recommendations might adequately encompass metastatic lymph nodes while sparing the organs at risk and reducing adverse events.

Watershed microinfarct pathology and cognition in older persons.

Brain microinfarcts are common in aging and are associated with cognitive impairment. Anterior and posterior watershed border zones lie at the territories of the anterior, middle, and posterior cerebral arteries, and are more vulnerable to hypoperfusion than brain regions outside the watershed areas. However, little is known about microinfarcts in these regions and how they relate to cognition in aging. Participants from the Rush Memory and Aging Project, a community-based clinical-pathologic study of aging, underwent detailed annual cognitive evaluations. We examined 356 consecutive autopsy cases (mean age-at-death, 91years [SD= 6.16]; 28% men) for microinfarcts from 3 watershed brain regions (2anterior and 1 posterior) and 8 brain regions outside the watershed regions. Linear regression models were used to examine the association of cortical watershed microinfarcts with cognition, including global cognition and 5 cognitive domains. Microinfarcts in any region were present in 133 (37%) participants, of which 50 had microinfarcts in watershed regions. Persons with multiple microinfarcts in cortical watershed regions had lower global cognition (estimate=-0.56, standard error (SE)= 0.26, p= 0.03) and lower cognitive function in the specific domains of working memory (estimate=-0.58, SE= 0.27, p= 0.03) and visuospatial abilities (estimate=-0.57, SE= 0.27, p= 0.03), even after controlling for microinfarcts in other brain regions, demographics, and age-related pathologies. Neither the presence nor multiplicity of microinfarcts in brain regions outside the cortical watershed regions were related to global cognition or any of the 5 cognitive domains. These findings suggest that multiple microinfarcts in watershed regions contribute to age-related cognitive impairment.

Possible role of standardized echography complementing ultrasound biomicroscopy in tumors of the anterior eye segment: a study in a series of 13 patients

To evaluate the efficacy of standardized A-scan echography (ASE) complementing ultrasound biomicroscopy (UBM) to propose the most efficient method as grounds for the diagnosis, treatment, and follow-up of anterior eye-segment tumors. The inclusion criteria were tumors of the ciliary body and peripheral choroidal tumors, whose anterior border could not be visualized with a 10MHz ultrasound probe. The largest basal dimension and the highest prominence of the tumor were measured with a UBM Lin 50 probe. A standardized A-scan examination determined the tumor's thickness and internal reflectivity. Thus, tissue differentiation led to a standardized echography-based diagnosis (SED). The study included 13 patients. SED was achieved in all examined tumors. The smallest thickness of the tumor of the ciliary body enabling SED was only 1.78mm. The highest prominence of the tumor (3.66 ± 1.39mm) was generally larger than its thickness (3.30 ± 1.71mm). When approaching ciliary body tumors, both ASE and UBM should be performed, the former to accurately differentiate the tumor and measure its height, and the latter to delineate anterior tumor margins and iris involvement. Standardized echography-based diagnosis was grounds for further evaluation and/or treatment in this case series. The highest prominence of the ciliary body tumor perpendicular to the sclera as evidenced by UBM was generally higher than the thickness obtained with standardized echography. Hence, we propose ASE thickness to be the grounds for staging the severity of ciliary body tumors in the algorithm for their management.

Does the Anatomy of the Transected Pancreatic Neck Influence Post Whipple’s Operation Pancreatic Fistula?

Few studies correlate anatomical parameters of the transected pancreatic neck to occurrence of the dangerous complication-post Whipple's pancreaticoduodenectomy pancreatic fistula. To evaluate the correlation between anatomical details of the transected neck of the pancreas and post-operative pancreatic fistula (POPF) following Whipple's pancreaticoduodenectomy. Observational study. The study included 66 patients undergoing Whipple's pancreaticoduodenectomy with pancreaticojejunostomy at tertiary care centre between December 2009 and December 2014. Student's t test, Fisher's exact test, Pearson's chi-squared test and forward stepwise. Clinically relevant POPF (grade B and C) was noted in 12 patients. Morbidity/mortality was 30.30% and 4.54% respectively. Among the fistula v/s no fistula groups, (a) mean thickness of the pancreatic stump was 12.17 ± 1.40mm v/s 14.94 ± 1.87mm (P = 0.000), (b) mean width of the pancreatic stump was 24.33 ± 4.14mm v/s 25.87 ± 4.02mm (P = 0.238) and (c) mean pancreatic duct (PD) diameter was 2.92 ± 0.79mm v/s 4.27 ± 1.39mm (P = 0.001). Mean distances of PD from anterior, posterior, superior and inferior pancreatic borders in the fistula group v/s no fistula group were 6.08 ± 1.62mm, 3.17 ± 0.72mm, 9.92 ± 2.15mm, and 11.42 ± 3.45mm v/s 5.93 ± 1.71mm, 4.83 ± 1.26mm, 11.83 ± 2.79mm and 9.96 ± 3.25mm respectively. Eleven of 38 patients (28.9%) with soft pancreas developed POPF. Pancreatic duct < 3mm diameter, < 3mm from posterior border, < 12mm from superior border, pancreatic neck thickness < 12mm and soft pancreas consistency were significantly associated with POPF.

Radiographic Study of Lumbar Sympathetic Trunk in Oblique Lateral Interbody Fusion Surgery

Oblique lateral interbody fusion (OLIF) surgery provides a convenient and minimal access to the lesion disc with few complications; however, the left lumbar sympathetic trunk (LST) lies in the surgical field with a certain incidence of injury. The aim of this study was to describe the anatomic structures of the left LST at risk for injury during OLIF at different lumbar segment levels based on radiologic evaluations. Forty-four healthy young people (22 men and 22 women) were recruited, and routine lumbar magnetic resonance radiograph was performed. The LST, abdominal aorta (AA), and psoas muscle (PM) were observed, and all parameters were acquired using axial T2-weighted turbo spin echo sequence images. Independent-samples t test, 1-way analysis of variance test, and Least significant difference test were used to explore the LST's tract and the anatomic relationship with the adjacent anatomic landmarks at different levels. The distance from the left lateral border of the AA to the anterior medial border of the left PM was significantly narrowing from the L2-3 to L4-5 segment levels (13.72 ± 3.00, 11.78 ± 2.69, and 9.18 ± 3.43 mm). The distance from the left lateral border of the AA to the left LST was also significantly decreased from the L2-3 to L4-5 segment levels (11.14 ± 2.89, 9.36 ± 2.79, and 6.63 ± 2.94 mm). However, the distance from the leading edge of the left PM to the left LST had no statistical differences among all adjacent segment levels (2.96 ± 0.62, 2.83 ± 0.62, and 3.07 ± 0.86 mm). The location of the left LST is more backward and lateral at level L2-3, whereas it is inside front at levels L3-4 and L4-5. The practical risk of LST injury in different segment levels varied with specific anatomic conditions. The segment level L2-3 could provide a safer surgical space for OLIF, and the risk of the left LST injury might be greater during OLIF at level L4-5.

A simple method to locate mandibular foramen with cone-beam computed tomography and its relevance to oral and maxillofacial surgery: a radio-anatomical study.

The mandibular foramen (MF) cannot be palpated clinically and its location is variable at the medial surface of mandibular ramus. Nevertheless, determining its exact location is very important to the oral and maxillofacial surgeon for the relevant anesthetic and surgical ramus procedures. The aim of this study was to analyze the position of MF using cone-beam computed tomography (CBCT) to help the surgeon in identifying reliable 'target area' for the inferior alveolar nerve (IAN) block and 'safety zone' for mandibular ramus osteotomies approached extra-orally. This radio-anatomical study examined all CBCT radiographs for patients treated over 2years. Distances from MF to the anterior (A) and posterior (P) borders of the ramus, mandibular incisura (MI), mandibular notch (MN), and mandibular occlusal plane (O) were measured by a reliable examiner, followed by calculation of ratios to determine the horizontal and vertical position of MF. Patients' details were then recorded. Student's t test and One-Way-ANOVA test were used to analyze data. A total of 210 CBCT radiographs were included and belonged to 210 subjects; 91 males (43.3%) and 119 (56.7%) females, with mean age (± SD) of 43.70 ± 19.08years. The horizontal and vertical positions of MF differed significantly (P < 0.001) according to age, but generally calculated at least 40% of AP and MIMN distances from P and MI, respectively. This study suggested the '40% rule' to locate the 'target area' for IAN block and 'safety zone' for ramus osteotomies approached extra-orally.

Histomorphometric analysis of the choroid of donkeys, buffalos, camels and dogs.

The present study was carried out to investigate the morphological and histomorphometric characters of choroid in donkeys, buffalos, camels and dogs. The findings of the study revealed that, macroscopically, the choroid was consisted of two areas in all studied animals, except in camel which consists of one area. Histologically, the choroid consists of five layers. Interestingly, the anterior borders of all investigated animals were free of pigments except in camel. Morphometric analysis revealed significant species differences in the mean total thickness of the choroid and its different layers. In addition, significant differences were also found between the ratios of the means of different layers to the total thickness of the choroid. In conclusion, these variations might be related to the different lifestyles and visual behavior of the investigated animals.

Fat infiltration in the gluteus minimus muscle in older adults.

PurposeFat infiltration (FI) in the gluteus minimus muscle (GMin) has been reported as being restricted to the anterior part. The aim of this study was to verify whether FI is localized only to the anterior part of the GMin through the dissection of large number of elderly cadavers and to clarify the underlying mechanism of FI localized to a specific region.Materials and methodsThirty-eight hips from 20 embalmed elder cadavers were dissected for verification of FI localization. The samples of three regions – the fat infiltrated region of the anterior part (FI), the region without FI (non-FI), and the posterior region – were harvested from nine hips for the histological fiber type assessment.ResultsThe FI area was distributed at 2.6°–38° from the anterior border within the anterior part, of which function is responsible for hip extension and internal rotation and is likely reduced by disuse following aging. The number of type I fibers was lowest in FI, followed by non-FI, while the number of type I fibers was highest in the posterior. Meanwhile, the number of type II fibers was equivalent across the three regions. Atrophic type II fibers were observed in overall samples of the three regions, and grouped atrophy, which is evidence of denervation, was observed in FI and non-FI samples. Type grouping, which suggests to be reinnervated, was found in the non-FI and posterior samples but very little in the FI samples.ConclusionFI in the GMin in older adults restricted to deep within the anterior part is secondary to disuse and is strongly related to impaired denervation–reinnervation process.

Posterior spinal canal decompression with screw fixation and reconstruction of three vertebral column for thoracolumbar burst fractures complicated with nerve injury

To explore the feasibility and clinical effect of posterior spinal canal decompression with pedicle screw fixation and reconstruction of anterior and middle vertebral column for thoracolumbar burst fractures complicated with nerve injury. A total of 36 patients with thoracolumbar burst fractures treated from March 2011 to April 2016 were enrolled in the retrospective study. There were 20 males and 16 females, aged from 21 to 52 years old with an average of 37.6 years. All the fractures were located on a single segment, 8 cases of T11₁₁, 10 cases of T₁₂, 12 cases of L₁, 6 cases of L₂. According to thoracolumbar injury classification and severity score(TLICS) system, the score was 7 to 9 points, with an average of 7.4 points. According to the America Spine Injury Association(ASIA) grade, 4 cases were type A, 10 cases were type B, 14 cases were type C, 8 cases were type D. All the patients underwent posterior spinal canal decompression with pedicle screw fixation and reconstruction of anterior and middle vertebral column. The recovery of nerve function was evaluated by ASIA grading. The correction of kyphosis(Cobb angle), the volume change of injuried spinal canal, the change of anterior border height of injury vertebra which can be observed by X-rays;the internal fixation loosening and breakage and all the information of bone fusion were recorded. All the operations were successful, the mean operative time and intraoperative blood loss were(2.8±0.3) h (2.1 to 3.5 h) and (880±120) ml(550 to 1 350 ml), respectively. All the incisions got primary healing. All the patients were followed up for 12 to 28 months with an average of 18.4 months. All the patients obtained satisfactory bone fusion. No pseudoarticulation formation was found, and there was no loosening, breakage of pedicle screws or displacement of titanium mesh. Neurological function was improved in different degree, except in one patient with grade A and another one with grade B. According to the ASIA grade, there were 1 case of type A, 1 case of type B, 7 cases of type C, 10 cases of type D and 17 cases of type E, postoperatively. At 3 days after operative, the anterior border height of injury vertebra, Cobb angle and the volume changes of injury spinal canal were obviously improved(P<0.05), and there was no significant difference between postoperative at 3 days and final follow-up(P>0.05). Spinal canal decompression with screw fixation and reconstruction of anterior and middle vertebral column through posterior midline approach is a safe and effective method in the treatment of thoracolumbar burst fractures with nerve injury, it is worthy to be popularized. It can complete the spinal canal decompression of 360 degree, reduction of fractures and reconstruction of vertebral three-column at the same time through a single posterior approach. The advantages includes less trauma, perfect decompression, good stability and etc.

Effect observation of percutaneous pedicle screw fixation combined with percutaneous vertebroplasty for the treatment of osteoporotic thoracolumbar fractures

To evaluate the clinical effects of percutaneous pedicle screw fixation(PPSF) combined with percutaneous vertebroplasty(PVP) for the treatment of osteoporotic thoracolumbar fractures. The clinical data of 94 patients with osteoporotic thoracolumbar fractures treated from January 2014 to December 2015 were retrospectively analyzed. There were 31 males and 63 females, aged from 65 to 70 years old with an average of 67.2 years. Fracture level was T₁₁ on 15 cases, T₁₂ on 32 cases, L₁ on 29 cases and L₂ on 18 cases. The patients were divided into two groups according to different therapeutic methods. Percutaneous pedicle screw fixation combined with percutaneous vertebroplasty were applied in 43 patients(group A) and percutaneous vertebroplasty was applied to 51 patients(group B). Operation time, intraoperative blood loss, bone cement volume, postoperative in-bed time were recorded; preoperatively, 3 d, 1 year after the operation, the ratios of anterior border heights, sagittal Cobb angles, visual analogue scale(VAS) scores were compared between two groups. The condition of postoperative complication in two groups was analyzed. All the patients were followed up for 12 to 24 months with an average of 18.5 months. Operation time of group A [(96.2±28.7) min] was longer than that of group B [(31.8±10.6) min]. Intraoperative blood loss of group A[(62.2±25.5) ml] was more than that of group B [(25.4±10.9) ml]. Bone cement volume of group A [(5.5±0.5) ml] was larger than that of group B [(4.9±1.1) ml]. Postoperative in-bed time of group A[(5.1±1.8) d] was longer than that of group B[(1.8±0.7) d]. There were significant differences in operation time, intraoperative blood loss, bone cement volume, postoperative in-bed time between two groups(P<0.05). Three days, 12 months after the operation, the ratios of anterior border heights and Cobb angles in two groups were significantly improved. At final follow-up, the ratio of anterior border height and Cobb angle of group A[(85.6±3.5)%, (11.9±5.3)°] were better than of group B[(84.2±4.5)%, (15.3±3.4)°](P<0.05). Three cases in group B had re-collapse of cemented vertebral bodies. Postoperative at 3 d, 1 year, VAS score of all patients had significantly decreased(P<0.05), and there was no significant difference between two groups(P>0.05). Compared to simple PVP, PPSF combined with PVP in treating osteoporotic thoracolumbar fracture can obtain stronger vertebral strength and stiffness, furthermore to improve vertebral reduced effect, keeping vertebral heights, and preventing vertebral re-collapse.

A case of third branchial cleft cyst

Branchial cyst or congenital cystic lesions of neck originate from branchial clefts, the 2nd branchial cleft cyst being the most common and 3rd and 4th being missed. Hence, they are often misdiagnosed as lymph nodal masses, cold abscess. We are reporting a case of 3rd Branchial cleft cyst, of a 12-year-old boy who presented with left sided recurrent painful cystic mass at the level of hyoid bone going down to the level of pyriform fossa. All the tests for tuberculosis were negative. USG neck revealed loculated thick walled cyst from SCM to lateral part of pharynx. CECT revealed a thick-walled cyst extending from the anterior border of the sternocleidomastoid going down obliquely below the level of thyrohyoid membrane to pyriform fossa. Exploration revealed a thick walled infected cyst, pushing left upper pole of thyroid medially and anterior to left sided superior laryngeal nerve. The cyst was going downwards medially below the level of thyrohyoid membrane. The cyst was excised completely. Histopathology revealed the findings of squamous epithelial lining of cyst wall and cholesterol crystals within. Detailed anatomy on CECT, surgery and histopathology confirmed 3rd arch Branchial cyst.

Arthroscopic Fixation of Traumatic Tibial Bone Avulsion of Posterior Cruciate Ligament Using Scorpion Suture Passer: A New Technique

Several operative techniques have been described for operative treatment of posterior cruciate ligament (PCL) avulsion injuries. Here we introduce a new arthroscopic suture technique for the treatment of PCL avulsion fracture using Scorpion suture passer. Three standard portals of anteromedial, anterolateral, and posteromedial are established along with the central trans-patellar tendon portal, if necessary. A Scorpion suture passer and No. 2 FiberWire were used to put two sutures at the base of the PCL-bone interface. After reducing the fragment, a tibial target guide for PCL was used to make a tunnel at the center of the fracture site and the fragment, if possible. An Endotack is used to fix the sutures at the anterior border of the tibia. This is a practical technique with a short learning curve and biomechanically stable fixation.

The Relationship of the Articular Eminence with the Mandibular Fossa: Implications for Temporomandibular Joint Mechanics

The temporomandibular joint varies from most joints in that it is ginglymoarthrodial, both a hinge and a gliding joint. Early opening of the mouth produces a rotational movement at the joint; however, with wide mouth opening, the mandibular condyle translates anteriorly beyond the articular eminence. In some circumstances, the translation of the mandibular condyle over the articular eminence produces a dislocation of the mandible with concomitant spasm of local musculature, thereby holding the mandible in an open position. In certain circumstances, conservative treatments may prevent future dislocations. However, occasionally, surgeries such as eminectomy may be warranted. Because of the aforementioned relationship of the articular eminence with the movement of the mandible, the anatomy of the articular eminence warrants study in order to attain a better understanding of the temporomandibular joint mechanics. Therefore, this study assessed the angle formed by the anterior and posterior boundaries of the articular eminence and the angle formed between the posterior border of the mandibular fossa with the anterior border of the mandibular fossa (i.e., the posterior border of the articular eminence)—angles A and B, respectively. A total of 102 left sides and 99 right sides were analyzed. The average angle A was 112.5±14.49° (Mean±SD) and the average angle B was 112.4±13.28°. Angles A and B were correlated (r=0.41; p&lt;0.0001). Paired t‐tests revealed no statistically significant difference between angle A, bilaterally (t=1.543(80); p=0.1268). However, there was a statistically significant difference between left‐ and right‐sided angle B (t=4.045(77); p=0.0001). The results of this study suggest that there is bilateral asymmetry among mandibular fossae. Similarly, the anterior and posterior boundaries of the articular eminence do not differ significantly from side‐to‐side. Further study should incorporate the size of the articular eminence and mandibular fossa in relation to the angular data presented here.Support or Funding InformationWV Research Challenge Fund [HEPC.dsr.17.06] and [HEPC.dsr.14.13]This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Anterolateral Triangle: A Cadaveric Study with Neurosurgical Significance.

The anterolateral triangle is one of 10 surgical triangles of the cavernous sinus and serves as an important anatomic landmark for the skull base surgeon. There are few studies in the English literature that have precisely defined and measured the borders of the anterolateral triangle and little agreement has been made regarding the nomenclature within the English literature. A total of 12 midsagittally hemisected adult human cadaveric head halves were dissected to expose the anterolateral triangle. The triangle was defined and measurements of the anterior, posterior, and lateral borders were taken. The mean lengths and standard deviations of the anterior, posterior, and lateral borders were 8.3 ± 2.2 mm, 5.9 ± 2.0 mm, and 11.5 ± 2.9 mm, respectively. The mean area and standard deviation were 20.46 ± 9.30 mm2. The anterolateral triangle is helpful in understanding and planning surgical approaches to the cavernous sinus and middle cranial fossa. As such, normal anatomic relationships and the sizes of the anterolateral triangle must first be recognized to better access the pathologic changes within and around this region.

Zone de sécurité de la tête radiale : une nouvelle méthode de localisation sur les coupes axiales tomographiques

PurposeDirect location of the “safe zone” on a CT axial view is impossible because the radial head is circular in shape. Previous “safe zone” location methods are not appropriate if the physician is unable to visualize the actual radial head. This study aims to introduce a new method to locate the “safe zone” on CT. MethodsCT scans were performed on 20 intact cadaveric upper limbs from 20 different corpses in full pronation and supination. The DICOM-format raw data were then re-sliced and analyzed in Mimics 17.0 (Materialise, Belgium). The radial interosseous border (IB) is shaped like a droplet on the axial view; its axis was selected as our reference line (RL). A parallel line in the radial head axial slice was created, and its position relative to the “safe zone” was studied. Deviation in RL direction was evaluated. ResultsSafe-zone scope was 114.41°±11.99. The rotation angle from the RL to the safe-zone's anterior and posterior border was 215.03°±5.99 and 100.62°±8.12, respectively. Rotation direction (clockwise or anti-clockwise) depended on relative radius-ulna position. The safe zone was located by determining these two borders. The reference line's direction was stable in the upper half of the IB; its distance to the radial head fovea was 77.33°±6.24mm. ConclusionsThe radial head “safe zone” can be located on CT axial view based on the upper half of the IB using this new method. The method is clinically applicable to determine whether postoperative elbow malrotation results from plate impingement.

Effects of mechanical loading on cortical defect repair using a novel mechanobiological model of bone healing.

Mechanical loading is an important aspect of post-surgical fracture care. The timing of load application relative to the injury event may differentially regulate repair depending on the stage of healing. Here, we used a novel mechanobiological model of cortical defect repair that offers several advantages including its technical simplicity and spatially confined repair program, making effects of both physical and biological interventions more easily assessed. Using this model, we showed that daily loading (5N peak load, 2Hz, 60 cycles, 4 consecutive days) during hematoma consolidation and inflammation disrupted the injury site and activated cartilage formation on the periosteal surface adjacent to the defect. We also showed that daily loading during the matrix deposition phase enhanced both bone and cartilage formation at the defect site, while loading during the remodeling phase resulted in an enlarged woven bone regenerate. All loading regimens resulted in abundant cellular proliferation throughout the regenerate and fibrous tissue formation directly above the defect demonstrating that all phases of cortical defect healing are sensitive to physical stimulation. Stress was concentrated at the edges of the defect during exogenous loading, and finite element (FE)-modeled longitudinal strain (εzz) values along the anterior and posterior borders of the defect (~2200με) was an order of magnitude larger than strain values on the proximal and distal borders (~50-100με). It is concluded that loading during the early stages of repair may impede stabilization of the injury site important for early bone matrix deposition, whereas loading while matrix deposition and remodeling are ongoing may enhance stabilization through the formation of additional cartilage and bone.