Deniz Demiryürek

Variations in anatomy at the suprascapular notch possibly causing suprascapular nerve entrapment: an anatomical study

The purpose of the study was to determine anatomical variations at the suprascapular notch for better understanding of possible predisposing factors for suprascapular nerve entrapment. We dissected 32 shoulders of 16 cadavers between the ages of 39 and 74 years. We observed abnormally oriented superior fibers of the subscapularis muscle in five shoulders of the 16 cadavers, which were covering the entire anterior surface of the suprascapular notch and significantly reducing the available space for the suprascapular nerve. We also detected anterior coracoscapular ligament in six of the 32 shoulders, and calcified superior transverse scapular ligament in four of the shoulders. In this study, we classified the variations for the superior transverse scapular ligament. In conclusion, knowing the anatomical variations in detail along the course of the suprascapular nerve might be important for better understanding of location and source of the entrapment syndrome, especially for individuals who are involved in violent overhead sports activities such as volleyball and baseball. To our knowledge, close relationship of subscapularis muscle with the suprascapular nerve as a possible risk factor for suprascapular nerve entrapment has not been mentioned previously.

Infective agents in fixed human cadavers: A brief review and suggested guidelines

Cadavers remain a principal teaching tool for anatomists and medical educators teaching gross anatomy. Infectious pathogens in cadavers that present particular risks include Mycobacterium tuberculosis, hepatitis B and C, the AIDS virus HIV, and prions that cause transmissible spongiform encephalopathies such as Creutzfeldt‐Jakob disease (CJD) and Gerstmann‐Straussler‐Scheinker syndrome (GSS). It is often claimed that fixatives are effective in inactivation of these agents. Unfortunately cadavers, even though they are fixed, may still pose infection hazards to those who handle them. Specific safety precautions are necessary to avoid accidental disease transmission from cadavers before and during dissection and to decontaminate the local environment afterward. In this brief review, we describe the infectious pathogens that can be detected in cadavers and suggest safety guidelines for the protection of all who handle cadavers against infectious hazards. Anat Rec (New Anat) 269:194–197, 2002.

Minimally invasive plating of the distal tibia: do we really sacrifice saphenous vein and nerve? A cadaver study.

Objective: To investigate the risk of saphenous nerve (SN) and great saphenous vein (GSV) injury during percutaneous screw placement of the 3.5/4.5 LCP Distal Tibial Metaphyseal Plate and the 3.5-mm LCP Medial Distal Tibia Plate with tab in distal tibias of cadaver extremities. Methods: Thirty-one unpaired (1 fresh and 30 formalin fixed) adult cadaveric lower extremity specimens were dissected. Using the principles of minimally invasive plating, a 3.5/4.5 LCP Distal Tibial Metaphyseal Plate was implanted in 16 extremities and a 3.5-mm LCP Medial Distal Tibia Plate with tab in the remaining 15 extremities. Injuries to or any evidences of direct contact with the SN or GSV were recorded. Additionally, the shortest distances of each hole to the main branches of these anatomic structures were measured. Results: The risk of injury to the SN and GSV was higher in holes 4, 5, and 6 when using the 3.5/4.5 LCP Distal Tibial Metaphyseal Plate and in holes 3, 5, and 8 when using the 3.5-mm LCP Medial Distal Tibia Plate. Conclusions: The SN and GSV are at high risk for injury during percutaneous screw placement of the 3.5/4.5 LCP Distal Tibial Metaphyseal Plate and the 3.5-mm LCP Medial Distal Tibia Plate at the distal tibia. Careful dissection in the stab incisions down the plate, atraumatic placement of the drill sleeves, and protection of the soft tissues during screw insertion might decrease the risk of injury to the SN and GSV.

Recesses along the posterior margin of the infrapatellar (Hoffa’s) fat pad: prevalence and morphology on routine MR imaging of the knee

The objective is to evaluate the prevalence and morphology of recesses along the posterior margin of the infrapatellar fat pad on routine MR imaging of the knee. MR images of 213 knees in 204 consecutive individuals were evaluated with regard to the prevalence and morphology of recesses (a “suprahoffatic” recess close to the inferior border of the patella and the previously described “infrahoffatic” recess anterior to the inferior portion of the infrapatellar plica). The recesses were analyzed with regard to synovial effusion and the condition of the anterior cruciate ligament (ACL). Anatomic dissection was made in 29 knees in 16 cadavers to verify the presence of the suprahoffatic recess. The infrahoffatic recess was present in 45% of the knees and mostly linear in shape (44%). The suprahoffatic recess was detected in 71% of the knees (45% in cadavers). Very weak to moderate positive correlation was found between the synovial effusion or the condition of the ACL and the presence and dimensions of the recesses. An awareness of the recesses in the infrapatellar fat pad is important in order to distinguish between pathology and anatomic variants on routine MR imaging of the knee.

Rotator interval dimensions in different shoulder arthroscopy positions: A cadaveric study

The rotator interval was defined as a triangular structure, where the base of the triangle was the coracoid base, the upper border was the anterior margin of the supraspinatus, and the lower border was the superior margin of the subscapularis muscle-tendon unit. We evaluated the rotator interval dimensions in 15 shoulders from 10 lightly embalmed adult cadavers in 3 shoulder arthroscopy positions: 0 degrees of abduction and 30 degrees of flexion (beach chair [BC]), 45 degrees of abduction and 30 degrees of flexion (lateral decubitus 1), and 70 degrees of abduction and 30 degrees of flexion (lateral decubitus 2). In each shoulder position, measurements were made in neutral rotation (NR), 45 degrees of external rotation (ER), and 45 degrees of internal rotation (IR). The coracoid base lengthened with IR in all positions and shortened in ER in the lateral decubitus position but not in the BC position. Abduction significantly lengthened the coracoid base, which was shortest in the BC position with ER (24 +/- 4 mm) and longest in the lateral decubitus 2 position with IR (33 +/- 5 mm). The coracoid base, where sutures are placed during plication of the interval, was observed to lengthen and, therefore, loosen with IR and abduction. To prevent postoperative ER restriction, plication should be made in ER or neutral rotation when operating in the BC position and the degree of abduction should be decreased and the shoulder held in ER when operating in the lateral decubitus position.

Fine structure of the human coccygeal body: a light and electron microscopic study

There is only limited data on the microscopic structure of the coccygeal body in classical textbooks. Although there are several articles describing the light microscopic structure of the organ, the data presented are rather conflicting especially when comparing glomus tumors and normal coccygeal bodies. We therefore examined the pericoccygeal soft tissues histologically with the aim of obtaining further evidence. At the light microscopic examination, coccygeal bodies were distinguished as sections of several blood vessels encapsulated by a connective tissue capsule. Small arteries within the coccygeal bodies had an unusual endothelial lining, resembling pseudostratified epithelium or neuro-epithelium. We observed increased numbers of glomus cells in a few samples. A highly tortuous course run by the small arteries was observed in the serial sections. At their electron microscopic examination, endothelial cells exhibited the features of columnar epithelial cells, though some appeared to be vacuole rich. The basal surface of the cells showed basal infoldings, but not as extensive as those of absorptive cells. External lamina, subplasmalemmal vesicles, bundles of microfilaments, groups of membrane bound organelles including mitochondria and endoplasmic reticulum were observed in glomus cells. In conclusion, it is rather difficult to use the term tumor for the coccygeal bodies when relying solely on the number of cells observed, because some segments of the coccygeal bodies were rich in glomus cells. It is more likely that the coccygeal bodies show variability in different individuals. The characteristics of the endothelium of the small arteries in coccygeal bodies needs to be examined in a wider range of specimens in order to be validated as a unique entity.

Association of Medial Meniscus Extrusion With the Prominence of a Fascicular Capsulofemoral Band Subjacent to the Deep Medial Collateral Ligament

OBJECTIVE The objective of our study was to test our hypothesis that a transverse oblique fascicular anteromedial capsulofemoral band partially subjacent to the deep medial collateral ligament (MCL) is more prominent in knees with medial meniscal extrusion. MATERIALS AND METHODS We retrospectively analyzed all knee MRI examinations from a 6-month period for the presence and dimensions of the anteromedial capsulofemoral band on coronal proton-density fat-saturated images and also for medial meniscus extrusion, which was defined as extrusion of 3 mm or greater. Edemalike signal intensity within or in the vicinity of the anteromedial capsulofemoral band, partial or complete tears of the MCL, a history of MCL surgery, or a neoplastic mass lesion violating the medial supporting structures were exclusion criteria. We reviewed procedural videos of patients who subsequently underwent knee arthroscopy. MRI of a cadaveric knee was performed and was followed by dissection and histologic examination. RESULTS MRI examinations of 346 knees of 312 patients met the inclusion criteria; of these knees, 50 had medial meniscus extrusion. The anteromedial capsulofemoral band was discernible on MRI in all knees except five (98.6%), and it was visible in six of the arthroscopy videos of 17 knees. The anteromedial capsulofemoral band was thicker on MRI of patients with medial meniscus extrusion (p < 0.0001). The anteromedial capsulofemoral band was identified on MRI and at dissection of the cadaveric knee, and histologic examination revealed that the anteromedial capsulofemoral band was a capsuloligamentous structure. CONCLUSION A transverse oblique anteromedial capsulofemoral band subjacent to the deep MCL is thicker in knees with medial meniscus extrusion.

The triticeous cartilage: redefining of morphology, prevalence and function

BACKGROUND Triticeous cartilage is a small cartilaginous component of the laryngeal skeleton. This cartilage, located in posterior end of the thyrohyoid ligament, presents in different shapes. Radiological studies indicate clinical and anatomical importance of the triticeous cartilage but these studies have limited information due to inadequate inspection method. Computed tomographic angiography is able to evaluate the triticeous cartilage with using three-dimensional images in more detail. The aim of this study is to describe prevalence and morphological properties of the triticeous cartilage. MATERIALS AND METHODS We examined computed tomographic angiography images of 746 patients (368 women, 378 men) retrospectively. Shapes, calcification degrees, volumes, lengths and wideness of the triticeous cartilage were evaluated by OsiriX-Lite software. RESULTS According to our results, triticeous cartilage presents common in the examined population (68.1%). The prevalence of the triticeous cartilage was higher in men than in women. We also found that the degree of calcification was not related with age and gender. CONCLUSIONS Clinical importance of the triticeous cartilage is that it could be misdiagnosed with atherosclerosis in common carotid artery because the triticeous cartilage is located almost at same level as the bifurcation of the common carotid artery. Therefore, clinicians should be aware about the triticeous cartilage.

Modified tension band wiring technique for olecranon fractures: where and how should the K-wires be inserted to avoid articular penetration?

OBJECTIVE Articular penetration of K-wires is a possible complication of the modified tension band wiring technique. However, there is no clear information or evidence regarding the entry point or introduction angle for K-wires to avoid this complication. The aim of this experimental study was to evaluate the effect of varying K-wire insertion points and angles on the risk for articular penetration during modified tension band wiring for olecranon fractures. METHODS All anatomical measurements were made on 50 cadaveric ulnas, and all other measurements were performed on exact foam replications of the 50 cadaveric ulnas. Morphometric measurements, including olecranon height and heights of the central, radial and ulnar facets of the semilunar notch, were taken. In the sagittal plane, articular angle and tubercle angle were measured. Two 1.6-mm parallel K-wires were inserted from 0, 5 and 8 mm anterior to the dorsal cortex of the olecranon process at angles of 20° and 30°. K-wire articular penetration was evaluated both visually and radiographically. RESULTS The mean central, radial and ulnar heights of the semilunar notch were 17.3 mm (14.7-20.0), 16.2 mm (12.0-21.0) and 15.8 mm (13.30-20.5), respectively. We observed no articular penetration at the 0-mm level at 20° and 30° (0 mm 20° and 0 mm 30°, respectively) or at 5 mm 20°. At 8 mm 30° wire introduction, more than 64% articular penetration was observed on either facet. The sequence from least to most likely to cause articular penetration was: 0 mm = 5 mm 20° > 5 mm 30° = 8 mm 20° > 8 mm 30°. The radial height of the semilunar notch was negatively correlated to the risk of articular penetration, when the wire was introduced at 8 mm 30°, 8 mm 20° and 5 mm 30° (all p<0.047). There were poor correlations between radiological and direct observational assessments, particularly for 8 mm 20° and 5 mm 30°. The frequency of intra-articular positioning for those observed to be radiologically extra-articular was 4/28 (14.3%) for 8 mm 30°, 4/7 (57.1%) for 8 mm 20° and 5/6 (83.3%) for 5 mm 30°. CONCLUSION When applying the modified tension band wiring technique to prevent articular penetration, K-wires should be inserted in the first 5 mm from dorsal cortex of the olecranon process at a maximum angle of 20°. Moreover, if the wires are required to be inserted more anteriorly because of the anatomical configuration of the fracture, they should be inserted at a shallow angle in the sagittal plane in relation to the proximal cortex of the ulna.