Side Of Cadaver Research Articles

Distal subsartorial compartment block of the saphenous nerve - A dissection study and a patient case series

Study objectiveA saphenous nerve block is an important tool for analgesia after foot and ankle surgery. The conventional midthigh approach to saphenous nerve block in the femoral triangle may impede ambulation by impairing quadriceps motor function. Primary objective: Developing a selective saphenous nerve block targeting the nerve distal to its emergence from the adductor canal in the subsartorial compartment. DesignThis study consists of A) a dissection study and B) Data from a clinical case series. SettingA) Medical University of Innsbruck, Austria (dissection of 15 cadaver sides) and.B) Aarhus University Hospital, Denmark (5 patients). InterventionsA) Five mL of methylene blue was injected into the subsartorial compartment distal to the intersection of the saphenous nerve and the tendon of the adductor magnus guided by ultrasound. B) Five patients undergoing major hindfoot and ankle surgery had a subsartorial compartment block with 10 mL of local anesthetic in addition to a popliteal sciatic nerve block. MeasurementA) The frequencies of staining the saphenous and medial vastus nerves. B) Assessment of postoperative pain by NRS score (0−10) and success rate of saphenous nerve block by presence of cutaneous anesthesia in the anteromedial lower leg, and motor impairment by ability to ambulate. Main resultsA) The saphenous nerve was stained in 15/15 cadaver sides. A terminal branch of the medial vastus nerve was stained in 2/15 cadaver sides. B) All patients were fully able to ambulate without support. No patients had any post-surgical pain from the anteromedial aspect of the ankle and foot (NRS score 0). The success rate of saphenous nerve block was 100%. ConclusionThe saphenous nerve can be targeted in the subsartorial compartment distal to the intersection of the nerve and the tendon of the adductor magnus. The subsartorial compartment block provided efficient analgesia without quadriceps motor impairment.

Endoscopically-Assisted Percutaneous Trigeminal Rhizotomy for Trigeminal Neuralgia: A Cadaveric Feasibility Study.

Objective Trigeminal neuralgia (TN) is a debilitating syndrome characterized by paroxysmal facial pain in one or more divisions of the trigeminal nerve. The etiology and treatment paradigms are still controversial. The endoscopically-assisted procedure has not yet been described in percutaneous procedures for TN. The aim of this study was to assess the utility and feasibility of endoscopic-assisted percutaneous approaches for trigeminal rhizotomy in TN. Methods This study comprised eight cadaveric sides heads that underwent an endoscopically assisted percutaneous approach using Hakanson's anterior puncture method for targeting the foramen ovale. Results V3 exiting the foramen ovale was easily visualized with the endoscope on all sides. While approaching the foramen ovale, distal branches of V3 such as the lingual and inferior alveolar nerves were first identified as they traveled between the medial and lateral pterygoid muscles. These branches were then traced proximally to the V3 trunk deep to the lateral pterygoid. Large arteries and veins were easily visualized and avoided in the trajectory to the foramen ovale. No gross injury to any neurovascular structure along the course of the needle insertion was identified. Conclusion We found that endoscopic-assisted percutaneous approach to the foramen ovale is feasible and allows for accurate canalization and anatomical identification of the precise location for rhizotomy under direct visualization. Such a procedure, after it is confirmed in patients, could offer a new technique for reducing unsuccessful canalization and could improve outcomes.

Submental island flap - should we be worried about lymph node transfer? An anatomical and histological study

The submental island flap has been increasing in popularity for both oncological and non-oncological reconstruction of the head and neck. However, the original description of this flap left it with the unfortunate designation as a lymph node flap. There has thus been significant debate on the oncological safety of the flap. In this cadaveric study the perforator system suppling the skin island is delineated and the lymph node yield of the skeletonised flap is analysed histologically. A safe and consistent approach to raising the perforator flap modification is described and the pertinent anatomy, and an oncological discussion with regards to the submental island perforator flap histological lymph node yield discussed. Ethical approval was received from Hull York Medical School for the anatomical dissection of 15 sides of cadavers. 6 x 4cm submental island flaps were raised following a vascular infusion of a 50/50 mix of acrylic paint. The flap size mimics the T1/T2 tumour defects these flaps would usually be used to reconstruct.The submental vascular anatomy, including length, diameter, venous drainage patterns, and the skin perforator system was documented. The dissected submental flaps were then histologically examined for the presence of lymph nodes by a head and neck pathologist at Hull University Hospitals Trust department of histology. The total length of the submental island arterial system, the distance from where the facial artery branches off from the carotid to the submental artery perforator entering the anterior belly of digastric or skin, averaged 91.1mm with anaverage facial artery length of 33.1mm and submental artery of 58mm. Vessel diameter for microvascular reconstruction was 1.63mm for the submental artery and 3mm for the facial artery. The most common venous anatomy drainage pattern was the submental island venaecomitantes draining to the retromandibular system then to the internal jugular vein. Almost half the specimens had a dominant superficial submental perforator allowing the ability to raise this as a skin only system. There were generally 2-4 perforators passing through the anterior belly of digastric to supply the skin paddle.73.3% (11/15) of the skeletonised flaps contained no lymph nodes on histological examination. The perforator version of the submental island flap can be safely and consistently raised with inclusion of the anterior belly of digastric. In approximately half the cases a dominant superficial branch allows for a skin only paddle. Due to the vessel diameter, free tissue transfer is predictable.Venous anatomy is variable and care needs to be taken when raising this flap. The skeletonised version of the perforator flap is largely devoid of nodal yield and on oncological review a 16.3% recurrence rate is equivalent to current standard treatment.

A marginal process of the zygomatic bone predicts a lateral exit of the zygomaticotemporal nerve: An anatomical study with application to surgery around the midface.

Previous studies have not verified the contents of accessory foramina of the zygomatic bone on dry skulls and thus could not conclude whether they carried accessory zygomaticofacial nerve branches or branches or the entire trunk of the zygomaticotemporal nerve (ZTN). Therefore, the aim of the current study is to present findings from cadaveric dissections to clarify this relationship. Fifty, fresh frozen, adult cadaveric sides underwent dissection of the ZTN. When identified, these nerves were quantified and their relationship to the zygomatic bone further documented by dissecting through the bone following the course of the nerve from a superficial to deep perspective. Additionally, 100 dry, adult, human skulls were analyzed looking for lateral foramina on the zygomatic bone. On three cadaveric sides (6%), the ZTN was found to pierce the zygomatic bone deeply and exit its superficial lateral surface. For dry skull specimens, a lateral zygomaticotemporal foramen (ZTF) was identified on nine sides (4.5%). For both groups, the presence of a strong marginal process of the zygomatic bone was strongly correlated to a ZTF exiting the lateral surface of the zygomatic bone. Although relatively uncommon, the ZTN can pierce the lateral aspect of the zygomatic bone and thus can be located superficial to the cheek. Such findings should be borne in mind during surgical or other invasive procedures in this area in order to minimize iatrogenic injury to the ZTN.

Endoscopic transoral approach to the lateral poststyloid space.

The lateral poststyloid space (LPSS) located at the posterolateral aspect of the styloid process. This study aims to explore the anatomical relationships in LPSS via a transoral corridor, providing reference for addressing lesions extending to this region. An endoscopic transoral approach for exposure of the LPSS was performed on 6 cadaveric specimens (12 sides). Related landmarks were explored, and transoral extirpation of tumors extended into LPSS was employed in 12 patients. The deep lobe of the parotid gland, extratemporal facial nerve, and the accompanying artery in the LPSS were sufficiently exposed via the transoral corridor in all 12 cadaveric sides. The transoral corridor provided adequate exposure for tumors extending to the LPSS, and en bloc resection was achieved in these 12 patients. No facial nerve or vascular injury occurred, and no recurrence observed in this cohort with an average follow-up of 26 months. An endoscopic transoral approach provides a direct access to the LPSS. Appreciation of the anatomical relationships within the LPSS is valuable for employing a transoral extirpation of tumors extending to this specific region.

Anatomy and clinical application of suprascapular nerve to accessory nerve transfer.

BACKGROUNDLoss of motor function in the trapezius muscle is one complication of radical neck dissection after cutting the accessory nerve (AN) during surgery. Nerve repair is an effective method to restore trapezius muscle function, and includes neurolysis, direct suture, and nerve grafting. The suprascapular nerve (SCN) and AN are next to each other in position. The function of the AN and SCN in shoulder elevation and abduction movement is synergistic. SCN might be considered by surgeons for AN reanimation.AIMTo obtain anatomical and clinical data for partial suprascapular nerve-to-AN transfer.METHODSTen sides of cadavers perfused with formalin were obtained from the Department of Human Anatomy, Histology and Embryology, Peking University Health Science Center. The SCN (n = 10) and AN (n = 10) were carefully dissected in the posterior triangle of the neck, and the trapezius muscle was dissected to fully display the accessory nerve. The length of the SCN from the origin of the brachial plexus (a point) to the scapular notch (b point) and the distance of the SCN from the origin point (a point) to the point (c point) where the AN entered the border of the trapezius muscle were measured. The length and branches of the AN in the trapezius muscle were measured. A female patient aged 55 years underwent surgery for partial SCN to AN transfer at Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology. The patient suffered from recurrent upper gingival cancer. Radical neck dissection was performed on the right side, and the right AN was removed at the intersection between the nerve and the posterior border of the SCM muscle. One-third of the diameter of the SCN was cut off, and combined epineurial and perineurial sutures were applied between the distal end of the cut-off fascicles of the SCN and the proximal end of the AN without tension. Both subjective and objective evaluations were performed before, three months after, and nine months after surgery. For the subjective evaluation, the questionnaire included the Neck Dissection Impairment Index (NDII) and the Constant Shoulder Scale. Electromyography was used for the objective examination. Data were analyzed using t tests with SPSS 19.0 software to determine the relationship between the length of the SCN and the linear distance. A P value of < 0.05 was considered as statistically significant.RESULTSThe whole length of the AN in the trapezius muscle was 16.89 cm. The average numbers of branches distributed in the descending, horizontal and ascending portions were 3.8, 2.6 and 2.2, respectively. The diameter of the AN was 1.94 mm at the anterior border of the trapezius. The length of the suprascapular nerve from the origin of the brachial plexus to the scapular notch was longer than the distance of the suprascapular nerve from the origin point to the point where the accessory nerve entered the upper edge of the trapezius muscle. The amplitude of trapezius muscle electromyography indicated that both the horizontal and ascending portions of the trapezius muscle on the right side had better function than the left side nine months after surgery. The results showed that the right-sided supraspinatus and infraspinatus muscles did not lose more function than the left side.CONCLUSIONBased on anatomical data and clinical application, partial suprascapular nerve-to-AN transfer could be achieved and may improve innervation of the affected trapezius muscle after radical neck dissection.

A prevalence study of the atlantomastoid muscle.

To contribute to the documentation and consideration of the prevalence of the atlantomastoid muscle in humans. Sixty formalin-fixed cadaveric sides were dissected for the presence of the atlantomastoid muscle (2 sides per donor). Laterality, origin, insertion, and other observable characteristics of the variant were recorded along with donor sex for comparative analyses. The atlantomastoid muscle was observed in nine sides (15%): two left side only, three right side only, and 2 bilaterally. The origin of the muscle was consistent from the transverse process of the atlas, lateral to both the insertion of obliquus capitis inferior and the origin of obliquus capitis superior. In one instance, the origin of atlantomastoid was continuous with the most superior tendinous slip of levator scapulae. The insertion of each atlantomastoid variant was the mastoid process, however, the precise location was variable. The atlantomastoid muscle is a common accessory muscle of the suboccipital region; the muscle was present in 15% of the cadaveric sides dissected in this study. Despite the notable prevalence of atlantomastoid muscles, there is little current literature dedicated to its study. Here, we document the first new information related to the prevalence of atlantomastoid since 1964 and discuss the development and potential clinical significance of the muscle.

Are the nerves supplying the anterior sacroiliac joint nociceptive?

Sacroiliac joint (SIJ) pain is often difficult to diagnose. Moreover, while its anatomical characteristics have been well studied, its innervation and the contributions of particular nerves remain controversial, especially in relation to posterior joint innervation. To our knowledge, previous studies have not investigated the presence of nociceptive fibres in the nerves innervating the anterior SIJ. Eight adult cadaveric sides underwent dissection of the anterior SIJ. Adjacent anterior rami were examined for branches to the anterior SIJ. Any branches contributing to the anterior SIJ were measured and then resected. These samples were fixed in formalin and substance P was identified immunohistologically. On all sides, 1-2 small branches (mean diameter of 0.33 mm) arose from the posterior aspect of the L4 anterior ramus (12.5%), the L5 anterior ramus (62.5%), or simultaneously from both the L4 and L5 anterior rami (25%). These branches had a mean length of 13.5 mm. All histological samples contained nerve tissue. All samples of nerve fibres traveling to the anterior SIJ were positive for diffuse substance P reactivity. There were no histological differences between sides or sex. Each of the branches identified as travelling to the SIJ exhibited similar positivity for substance P. This cadaveric study demonstrates that the anterior SIJ nerve fibres carry pain fibres. This new knowledge has application to patients with SIJ syndrome and to its various treatments including interventional approaches to SIJ pain.

Hamstring branches of the sciatic nerve as donors for neurotization of the superior gluteal nerve: A cadaveric feasibility study.

Although superior gluteal nerve (SGN) injury can have significant morbidity, to date, surgical strategies for its repair are scant in the literature. Specifically, neurotization options have not been explored. To address this deficiency in the literature, the current cadaveric feasibility study was performed. Via a transgluteal approach on 16 cadaveric sides, the proximal sciatic nerve and the entrance of the SGN into the gluteus medius and minimus were identified. Additionally, branches from the sciatic nerve to the hamstring muscles were traced proximally to confirm their position in relation to the sciatic nerve as a whole. These branches were cut at the level of the ischial tuberosity and teased away from the sciatic nerve proximally to the greater sciatic foramen and transferred superolateral to the SGN. The diameter of each nerve branch was measured as well as its available length for reaching the SGN. All branches of the sciatic nerve to the hamstring muscles arose from the anteromedial part of the nerve. The mean diameters of the branches to the semimembranosus, semitendinosus, and biceps femoris muscles were 2.1, 1.9, and 1.5 mm, respectively. The mean diameter of the SGN was 3.1 mm and the mean distance from this entrance point to the ischial spine was 7.2cm. The mean length of the donor nerve was 8.5cm. Based on our study, use of a tibial-innervated hamstring branch as a donor for nerve transfer to the SGN is feasible.

Novel Use of Nerve Branch to Sartorius as Donor for Intrapelvic Neurotization of the Sciatic Nerve and Its Contributions

Sciatic nerve injuries are relatively infrequent but extremely disabling for the patient. As injury to this nerve is relatively infrequent, there is little about its repair in the literature, especially within the pelvis. Twelve adult embalmed cadavers (24 sides) underwent exposure of the anteromedial thigh, inguinal region, and pelvic cavity. The sartorius muscle was identified in the anterior thigh, and its nerve branches from the femoral nerve were isolated and traced proximally to the femoral nerve trunk. The isolated sartorius nerve branches were further traced to the pelvic part of the femoral nerve. Next, the lumbosacral plexus was dissected on the posterior aspect of the pelvis so that its constituent parts were seen and followed distally to also visualize the most proximal part of the sciatic nerve. The previously dissected nerve branches to sartorius were then transposed to these constituent parts, and the ability for a tension-free anastomosis between these 2 nerves was evaluated. The branches ranged in diameter from 1.89 to 3.1 mm (2.88 mm). The average length of the nerves was 17.3 cm. Transposition of these branches to all ventral rami of the lumbosacral plexus in the pelvis and proximal sciatic (intrapelvic) nerve was possible on all cadaveric sides. Our cadaveric study found that nerve branches to the sartorius muscle can be transposed intrapelvically to the lumbosacral plexus and could provide tension-free anastomoses for neurotization procedures in patients with nerve injury.

Bifurcation of Common Carotid Artery in Relation to Vertebral Level in Nepalese: A Cadaveric Study

The principal arterial supply of the head and neck are the two Common Carotid Arteries (CCA), they ascend in the neck and each divides into two branches, the External Carotid Artery (ECA) supplying the exterior of the head, neck and the Internal Carotid Artery (ICA) supplying the cranial and orbital cavities. Atherosclerosis of the carotid arteries is a major cause of stroke and transient ischemic attack and it increases with age. The present study was observational based descriptive type, conducted to identify the CCA bifurcation in relation to cervical vertebral level. A total number of 18 cadavers (16 males and 2 females), right and left side of cadavers were studied by dissection method in the Department of Anatomy, NMCTH from February 2020 to February 2021. The ethical approval was taken from NMC- IRC (Ref no- 026-076/077). In present study the frequency of CCA bifurcation in sixteen male Nepalese cadavers (32 samples) on the right and left side was observed and found high level of bifurcation on 31.25% and 37.5% respectively and normal/ standard on the right and left on 68.75% and 62.5% and there were no findings of low bifurcation of CCA. In two female cadavers (4 observations) the level of bifurcation was same on both the side at the level of C3-C4. The Carotid artery injury is possible in different neurological and head and neck surgery. Therefore, the knowledge of variation in level of bifurcation of CCA in different population will be referential to reduce the iatrogenic injury.

Endoscopic frontal recess anatomy directed by the drainage pathways using the connecting plates as landmarks.

To investigate the anatomical features of frontal recess (FR) drainage, and the classification of FR cells and frontal sinus (FS). Fifty sides from 30 adult cadaver heads were examined. FR cells and FS along the drainage pathways were dissected under 0° and 70° endoscopic views using unique connecting structures between the uncinate process and the ethmoid bulla as landmarks. Connecting plates between the uncinate process and the ethmoid bulla were discovered and termed medial suprainfundibular plate (MSIP), which were observed on each cadaver head, and lateral suprainfundibular plate (LSIP) on 92% (46/50) sides. Separated by MSIP, two drainage pathways were identified and named medial pathways of the FR (MPFR) medial to the MSIP and the lateral pathways of the FR (LPFR) in the lateral side. Different drainage pathways of the FS were confirmed, in which drained into the MPFR in 37 and into the LPFR in 13 of the cadaver sides. MSIP is the critical landmark for the recognition of MPFR, LPFR, and the classification of FR cells. The FR resection along LPFR and MPFR facilitated excellent exposure of FS.

The arterial blood supply of the symphysis pubis – Spatial orientated and highly variable

BackgroundOpen surgical treatment of the pubic region and adductor related pathologies require an exact knowledge of the arterial blood supply of the symphysis pubis that seems furthermore important to explain the hematogenous occurrence of symphysitis. Pubic bone marrow oedema (PBME) is a frequent occurring magnetic resonance imaging finding in groin pain. However, even asymptomatic athletes present PBME and a correlation to the physical activity or higher blood flow was suggested. Data on the vascular anatomy of the symphysis pubis are rare. MethodsTen formaldehyde-embalmed cadavers were dissected, and the arterial blood supply was investigated and photographically documented. ResultsIn the majority of cases the following pattern was determined: superior–inferior epigastric artery (n=12 hemipelves), inferior - dorsal artery of the penis/dorsal artery of the clitoris (n=16), posterior- obturator artery (n=16 hemipelves), anterior- deep external pudendal artery (n=14 hemipelves). Besides variations for the deep external pudendal artery anteriorly, we observed a highly variable arterial supply, especially superior. Superior in 4/10 cadavers, inferior in 0/10 cadavers, posterior in 2/10 cadavers and anterior in 5/10 cadavers side variations were found. ConclusionThe symphysis pubis has a spatial and rich organized arterial blood supply with several variations. Despite the symphysis pubis is recognized as bradytroph, the high number of vessels is presumably required in stress situations for example in heavy training.

Surgical anatomy of the internal carotid plexus branches to the abducens nerve in the cavernous sinus

ObjectiveSympathetic branches to the abducens nerve derived from the internal carotid artery sympathetic plexus, while in the cavernous sinus, have been scantly described in the extant literature. Therefore, the present cadaveric study was performed to better elucidate this anatomy. Patients and methodsEighteen cadaveric sides underwent dissection. ResultsThe number of branches derived from the sympathetic plexus traveling with the internal carotid artery in the cavernous sinus was one on 11.1 %, two in 11.1 %, and three in 72.2 %. One side was found to have no branches (5.6 %). The mean diameter of the distance from the posterior border of the internal carotid artery, length, and diameter of the branches was 7.0 ± 4.1 mm, 2.9 ± 1.3 mm, and 0.4 ± 0.1 mm, respectively. Of 44 of 45 sympathetic branches, 97.8 % originated from the lateral wall of the cavernous part of the internal carotid artery with only one from the medial wall. ConclusionBased on our cadaveric findings, sympathetic connections between the internal carotid artery and the abducens nerve are common. Therefore, surgeons who operate in or near the cavernous sinus should be aware of such connections in order not to place unwanted tension on the cavernous part of the internal carotid artery or abducens nerve during dissection.

Anesthesia of the anterior femoral cutaneous nerves for total knee arthroplasty incision: randomized volunteer trial

Background and objectivesFor pain relief after total knee arthroplasty (TKA), an injection at the midthigh level may produce analgesia inferior to that of a femoral nerve block as the anterior...

The applied anatomy and clinical significance of the proximal, V1 segment of vertebral artery.

The aim of the study was to probe the morphological features of the proximal segment (V1) of vertebral artery (VA) in a sample of Chinese cadavers. The origin, course and outer diameter at origin of the pre-vertebral part of the VAs were evaluated in 119 adult cadavers. It was found that 94.12% of the VAs originated from the subclavian arteries, bilaterally. The variant origins were present in 5.88% of the cadavers and all originated directly from the arch of the aorta. All the variations were observed on the left side of male cadavers. The average outer diameters at origin of the normal and variation groups were 4.35 ± 1.00 mm and 4.82 ± ± 1.42 mm, respectively, p = 0.035. In the normal group, but not in the variation group, the average diameter in the males was significantly larger than that in the females (4.50 ± 0.99 mm, 3.92 ± 0.92 mm, respectively, p = 0.000). In addition, only 5 cadavers in the normal group had hypoplastic VAs (4.20%, 4 males, 3 right-sided). Vertebral artery dominance (VAD) was present in 91 (69 males) out of 112 cadavers and more common on the left (n = 48). In addition, 3 cadavers satisfied conditions for coexistence of VAD and vertebral artery hypoplasia. All 7 cadavers in the variation group exhibited VAD, which was more common on the right side (n = 5). The morphologic variations and frequencies described above have implications for the early prevention, abnormal anatomy detection, accurate diagnosis, safe surgery and endovascular treatment of cardiovascular and neurological disease.

Latissimus Dorsi-Rib Osteomyocutaneous Flaps for Composite Cranial Defects: A Case Series and Anatomical Study

PURPOSE: Latissimus dorsi-rib osteomyocutaneous flaps (LDRFs) are versatile in reconstructing compromised composite defects of the cranium. The flap restores the contour of the skull, protects the brain, and improves neurologic status. There are benefits to using autologous rib instead of alloplastic material; however, rib viability and flap success rely on adequate blood supply. Our aim was to present the outcomes of 6 patients treated with LDRF and provide an anatomical basis for this flap. METHODS: Six patients with cranial defects treated with LDRF were evaluated retrospectively. Defect size, etiology, previous reconstructive attempts, outcomes, and complications were assessed. Red latex was injected into the subscapular arterial system of 20 fresh cadaver sides. In the prone position, latissimus dorsi muscle was dissected from the ribs in a mediocaudal to superolateral direction to locate interconnecting vessels between the thoracodorsal and lateral posterior intercostal systems. The number, diameter and length of perforators, and distance from midline were measured. RESULTS: All patients had a history of ≥2 previous failed reconstructions. Defects were secondary to gunshot injury, post-CVA cranioplasty, postablation irradiation, and postfrontal intracranial hemorrhage cranioplasty. Three defects were reconstructed using 2 ribs, whereas the remaining 3 patients received 1 rib. A prolene mesh was used to fill in the donor site defects in 4 patients. Follow-up ranged from 6 to 35 months. All patients had stable reconstructions. Headache resolved in 2 patients after reconstruction, and neurologic status improved in 2 patients. An average of 13.75 perforators could be localized in each cadaveric latissimus dorsi muscle. No perforator was found for the seventh rib. Not all cadaver sides contained perforating vessels for the eighth and 12th ribs. The distance from the midline to the first perforator was not different between the ribs (P = 0.499). Perforator diameter and pedicle length tended to decrease at more inferior rib levels. The 10th rib (4.65 ± 2.01) followed by ninth rib (3.7 ± 1.63) had the highest number of perforators. The eighth and 12th ribs contained the least perforators. The eighth rib had the longest perforators (4.26 ± 1.52 cm). CONCLUSION: The LDRF can successfully address large composite cranial defects, provide support, and enhanced contour with negligible donor-site morbidity. The 10th followed by the ninth rib has the best vascular supply for this flap. If 2 ribs are considered for the flap, the ninth and 11th are recommended. If only 1 rib is necessary for reconstruction, the 10th is ideal.

Randomized trial of ultrasound-guided superior cluneal nerve block

Background and objectivesThe superior cluneal nerves originate from the dorsal rami of primarily the upper lumbar spinal nerves. The nerves cross the iliac spine to innervate the skin and subcutaneous...

Preoperative identification of the initial burr hole site in retrosigmoid craniotomies: A teaching and technical note.

When fashioning a retrosigmoid craniotomy, precise placement of the initial burr hole is crucial to avoid iatrogenic sinusal injury and to facilitate a corridor that allows for minimal cerebellar retraction. 3D CT reconstructions of 16 cadaveric sides were used to identify and measure three discrete anatomical points. These three points and distances between them were plotted onto the surface of the skull using a digital caliper to identify the optimal burr hole location. This technique was subsequently applied in 20 clinical cases. Optimal burr hole placement was achieved in 87.5% of specimens and, with minor refinement, 100% of clinical cases with no significant increase in operative time. Preoperative planning took an average of 10minutes. This technique for localizing the location of the initial retrosigmoid burr hole is a simple, safe, reliable, rapid, and inexpensive solution for surgeons who do not have regular access to neuronavigation.

The Morphology of the Infraorbital Nerve and Foramen in the Presence of an Accessory Infraorbital Foramen.

The accessory infraorbital foramen (AIOF) is an anatomical variation associated with the infraorbital foramen (IOF) and nerve (ION). Its occurrence and neural contents have clinical implications regarding failure of loco-regional anesthesia and risk of neural damage during surgical interventions involving the maxillary region. Thus, morphologic characterization of the AIOF and neural contents as well as the spatial relationships to the IOF are potentially useful for optimizing surgical procedures. Additionally, predictive features of the AIOF based on its relationship to IOF morphology could enable the surgeon to anticipate its presence and proceed accordingly. The purpose of this study was to determine whether the presence of an AIOF and its neural contents affected the size, shape, and composition of the IOF and ION. The specific hypothesis tested was that the topography and fascicular composition of the ION and IOF differs between individuals possessing an AIOF and those lacking this anatomical variant. Gross topographic features of the IOF (42 crania) were compared between specimens possessing (test) or lacking (control) an AIOF. Nerve fascicles of ION (60 cadaveric sides) were examined histologically and compared morphometrically between specimens presenting or lacking an AIOF. An additional sample of 30 crania was subjected to cone-beam computed tomography (CBCT) analysis to determine the course of the canal leading to the AIOF. The AIOF incidence was 47.6% (20 crania) and 32.1% of the sides (27 sides). A single AIOF was observed in 24 sides and double AIOF in three sides. The AIOF occurred bilaterally in 7 specimens (16.7%). The majority of AIOF (86.7%) were located superomedial to IOF. A slightly higher frequency of the AIOF was found in left side compared to the right. Using CBCT, a patient sample showed an AIOF incidence in 21 sides of 16 patients (65.6%). A single AIOF was observed in 19 sides. Only 1 double AIOF was found in the scans, whereas 3 were found in the dry skull group. The AIOF occurred bilaterally in 3 scans (10%). The majority of AIOF (90.4%) were located superomedial to the IOF based on the CBCT scans. The AIOF was consistently seen connected to the infraorbital canal and progressed superiorly and medially from the infraorbital canal to the maxillary surface. The size of the ION without an AIOF was not significantly different than the ION in the presence of an AIOF (1.45 × 10/1.32 × 10 μm, P < 0.35) based on fascicular area. However, the number of ION fascicles was greater in specimens without an AIOF compared to those showing this feature (15.15/12.71, P < 0.04) CONCLUSION:: Results indicate that the area of the ION is not affected by an AIOF, suggesting that the field of innervation of this area is not modified by its occurrence. However, the ION appears to divide more proximally into its component branches when the AIOF is present.