Reappraisal of the proximal tibia anatomy in Turkish population.

OBJECTIVE: Total knee arthroplasty has been popular in recent years. Morphometry of proximal tibia is important for surgeons to perform successful total knee arthroplasty. Aim of this study was to reappraise the proximal tibia morphometry. METHODS: In this study, 57 human dry tibia were evaluated. Anteroposterior and mediolateral dimensions of tibial condyles, maximum width of superior articular surface and length of tibia were measured. Furthermore, morphometric measurements of the intercondylar area and Gerdy's tubercle (infracondylar tibial tubercle) were done. All measurements were performed by two observers using a digital caliper. RESULTS: Mean anteroposterior and mediolateral dimensions of medial tibial condyle were found 39.76 and 23.27 mm, respectively. Mean anteroposterior and mediolateral dimensions of lateral tibial condyle were measured 34.72 and 21.83 mm, respectively. Mean anteroposterior dimension of intercondylar area was 41.62 mm. Shape of the Gerdy's tubercle was oval in 76.8%, irregular in 12.5%, and triangular in 10.7%. Texture of the tubercle was smooth in 85.7% and rough in 14.3%. Mean superoinferior and mediolateral dimensions of Gerdy's tubercle were 12.28 and 10.27 mm, respectively. Anteroposterior and mediolateral dimensions of tibial condyles were significantly higher (p < 0.05) for the medial condyle. Positive and statistically significant correlations were found between the tibial length and the other parameters (p < 0.05, r > 0.40). CONCLUSION: The morphometric data of tibial plateau are important for surgeons during total knee arthroplasty. The superoinferior and mediolateral dimensions of the Gerdy's tubercle, the distance between Gerdy's tubercle and tibial tuberosity, the distance between Gerdy's tubercle and lateral tibial plateau were measured for the first time in our study. The data obtained from this study can be used as a guideline in designing tibial component of the total knee prosthesis in Turkish population. In arthroplasty, patient-specific prosthetic implants may eradicate implant mismatch in the near future.

To wedge or not to wedge; A cadaveric comparison study of two medial malleolar osteotomy modalities.

OBJECTIVE: To quantify the surface area of the talus accessible with a uniplanar and a biplanar medial malleolus osteotomy. Our secondary purpose study is to quantify the amount of weightbearing area that each osteotomy effects on the tibial articular surface. PATIENTS AND METHODS: Eight ankle joint specimens were dissected for this study. The uniplanar osteotomy was performed first. A K-wire marked the limits of access at two different angles: 90° and 30°. The boundaries were marked with a skin marker. Wedges were then created on the tibia plafond, and the osteotomy was converted into a biplanar one. Measurements were repeated again for this osteotomy. The talus, the tibial plafond, and the medial malleolus were then excised. Images were taken and then electronically calibrated for two-dimensional digital measurement of accessible areas. Areas of perpendicular and 30-degree access were recorded for both osteotomies. The articular surface of the tibia was also measured, and an area analysis was performed to calculate the amount of weightbearing cartilage removed by each osteotomy. RESULTS: Almost the entire sagittal plane was accessible with both osteotomies. At a 30° angle, bone purchase was achieved for 67.7 % of the talar articular surface with the uniplanar osteotomy and for 74.8 % with the biplanar osteotomy. At a 90° angle, uniplanar osteotomy provided access to 32.7 % of the talar articular area, whereas the biplanar osteotomy achieved an average coverage of 52.8 %. The difference was statistically significant. On average, 25.3 % of the weightbearing area of the tibial plafond is affected when a biplanar osteotomy is performed. CONCLUSION: Medial malleolar osteotomy provides varying degrees of access to the talar dome depending on how it is performed. A wedge-shaped biplanar osteotomy provides greater access and is therefore more suitable for defects located deeper on the talar dome. Despite providing wider access, it results in greater disruption of the weightbearing cartilage of the tibial plafond. LEVEL OF EVIDENCE: Level V.

Estimating the optimal entry point of the antegrade femoral nailing: Previous and novel morphometric measurements.

OBJECTIVE: This anatomical study aimed to investigate the possible relationships between the proximal femur parameters and verify the optimal entry point in line with the medullary canal. METHODS: Both in single image series and 3D-MPR views, 63 femur bones were evaluated. One-millimeter multidetector computed tomography scans were collected and assessed by OsiriX-Lite version 8 and Horos v3.3.5. Entry point locations, projected and true femoral neck-shaft, anteversion, and newly defined nail entrance angles were measured. RESULTS: The entry points of 16 femurs were placed at the tip of the greater trochanter, and the remaining 47 femurs were in the trochanteric fossa (i.e., piriformis fossa). Thirty-three of the entry points found in the trochanteric fossa were overlapped by the greater trochanter. When the parameters of the right and left sides were compared, it was found that; projected neck angle, nail entrance angle, and the differences between true neck angle and nail entrance angle were found significantly different. The relationship between nail entrance angle and entry point localization was assessed, and the probability of the entry point being at the tip of the greater trochanter is 63 times greater when the NEA is below 90. CONCLUSION: This study has demonstrated that the ideal entry point for straight nails, which is based on the anatomic axis of the femur, is found mainly at the trochanteric fossa, and the greater trochanter overlapped 70.21% of them. LEVEL OF EVIDENCE: Level IV, Diagnostic Study.

Vestibular landmarks to minimize injury to the mental nerve during transoral endoscopic thyroidectomy-vestibular approach (TOETVA) procedure: an anatomical study / Puntos de referencia vestibulares para minimizar la lesión del nervio mentoniano durante el procemiento de abordaje vestibular de tiroidectomía endoscópica transoral (TOETVA): un estudio anatómico

SUMMARY: The aim of this study is to reveal the morphometry of the mental nerve to describe a safe zone for minimizing mental nerve damage during transoral endoscopic thyroidectomy-vestibular approach (TOETVA). This study was performed on 12 cadavers. Localization of mental foramen according to teeth, distances of buccogingival sulcus-lip (BG-L), mental foramen-midline (MF-Midline), mental foramen - buccogingival sulcus (MF - BG), commissure - branching point (Cm - Br), branching point - vertical projection of branching point on lower lip (Br - LVP), vertical projection of branching point on lower lip - commissure (LVP - Cm), commissure - midline (Cm - midline), angles of mental (AM), angular (AA) and labial branches (AL) and branching patterns were recorded. Type 1 was mostly found as branching pattern in this study (45.8 %). A new branching pattern (type 9) was found on one cadaver. Mental foramen was mostly located at level of second premolar teeth. According to morphometric results of this study; supero- lateral to course of angular branch and infero-medial to course of mental branch of mental nerve on lower lip after exiting the mental foramen were described as safe zones during surgery for preserving mental nerve and its branches.

RESUMEN: El objetivo de este estudio fue revelar la morfometría del nervio mental o mentoniano para describir una zona segura y de esta manera, minimizar el daño de este nervio durante la tiroidectomía endoscópica transoral-abordaje vestibular (TOETVA). Este estudio se realizó en 12 cadáveres. Se realizó la localización del foramen mentoniano según los dientes, distancias surco gingival-labio (BG-L), foramen mentoniano-línea mediana (MF-Midline), foramen mentoniano-surco gingival (MF-BG), comisura-punto de ramificación (Cm-Br), punto de bifurcación - pro- yección vertical del punto de bifurcación en el labio inferior (Br - LVP), proyección vertical del punto de bifurcación en el labio inferior - comisura (LVP - Cm), comisura - línea mediana (Cm - línea mediana), ángulos del mentón (AM). Se registraron ramos angulares (AA) y labiales (AL) y patrones de ramificación. El tipo 1 se encontró principalmente como patrón de ramificación en el 45,8 %. Se describe un nuevo patrón de ramificación (tipo 9) encontrado en un cadáver. El foramen mentoniano se localizaba mayoritariamente a nivel de los segundos premolares. Según los resultados morfométricos, supero-lateral al curso de la rama angular e infero-medial al curso de la rama mentoniana del nervio mentoniano en el labio inferior, después de salir del foramen mentoniano, se describieron las zonas seguras, para la cirugía y preservación del nervio mentoniano y de sus ramos.

Tendon of Flexor Carpi Radialis in carpal tunnel: a radiologic and cadaveric study

Background/aim: Carpal tunnel is an important anatomical passage that carries the flexor tendons into the hand. As there is still no consensus about its contents among the anatomy textbooks, the main purpose of this study was to identify the relations of the flexor carpi radialis tendon in the carpal tunnel. Materials and methods: This retrospective study was completed in April 2018 at authors' university's hospital. Seventy-four female and 44 male patients' wrists without any pathology were examined by using magnetic resonance images. The series of axial sections where the pisiform exist were evaluated by using T1 sequence and the structures in the carpal tunnel were identified. Results: Results of this study showed that the tendon of the flexor carpi radialis was found above the flexor retinaculum within its own septal compartment in all patients. Conclusion: According to the results, tendon of flexor carpi radialis crosses the wrist region superficial to the carpal tunnel. Thus, tendon of flexor carpi radialis doesn't have any effect on the carpal tunnel syndrome. Further cadaveric studies would be useful for identifying the contents of the carpal tunnel and morphological organization of the wrist.

Para-aortic lymphadenectomy: step by step surgical education video

Para-aortic lymph nodes are exclusively important for the staging of gynecologic malignancies. This surgical education video describes the step-by-step technique for para-aortic lymphadenectomy with anatomic landmarks in a cadaver.

Morphometric analyses of clavicle's nutrient foramen.

PURPOSE: Fractures of the clavicle, which has an important location and function in the upper extremity and shoulder joint, compose 10% of all fracture cases. During the osteosynthesis of clavicle fractures and in the post-operative period of patients, considering the detailed morphometric and topographic properties of the nutrient foramen of clavicle is important to avoid the disruption of arterial nutrition of the clavicle and prevent unexpected injuries. The aim of this study was to investigate the morphometric properties of the nutrient foramen of clavicle in more detail using computedtomography images. METHODS: Computed tomography images of 116 healthy individuals (56 women/60 men) who had no pathology history were included in the presented study. Computed tomography images were reconstructed three-dimensionally using free-licensed Horos v3.3.3 software. Then, distances from clavicle's nutrient foramen to sternal end, anterior and posterior edges of the clavicle were measured. Statistical analyses were completed using SPSS v21 software. RESULTS: Our results demonstrated that the nutrient foramen of clavicle was located closer to the sternal end of the clavicle. The shortest distance to the sternal edge of clavicle was measured as 3.3 cm. Analyses of gender differences indicated that statistically significant differences were in favor of men. However, topographic properties of the clavicle's nutrient foramen were not affected by age. CONCLUSION: Nutrient foramen is mostly located closer to the sternal end of clavicle. Especially during osteosynthesis of clavicle fractures at the sternal end, maintaining the arterial supply of clavicle is of great importance for increasing the post-operative life quality of patients.

Redefining the morphometry of subclavian vessels for clavicle fracture treatments.

PURPOSE: Clavicle fractures are common injuries in adults and children. Although neurovascular damage is rarely seen, acute subclavian artery pseudoaneurysms and injuries to subclavian vessels were reported for closed fractures of the clavicle. The aim of this study was to identify the morphological details of the subclavian vessels and their relation to the sternoclavicular joint and body of the clavicle. METHODS: 127 patients (66 females and 61 males) were evaluated using reconstructed three-dimensional computed tomographic angiographies. The point at which the subclavian artery crossed posterior to the clavicle was detected as a landmark. The medio-lateral distance between the sternal end of the clavicle, landmark, antero-posterior distance between the clavicle and the subclavian artery, diameter of the artery and vein, angle between the subclavian artery and vein, distance of the subclavian vein to the subclavian artery and the clavicle at the landmark were measured. Measurements were compared according to gender and right and left sides, and age correlation was determined. RESULTS: Morphometric relationship between the subclavian vessels and clavicle presented differences between genders. We measured the antero-posterior distance between the subclavian artery and the clavicle to be less than 1 cm (0.91 cm). CONCLUSION: The subclavian artery travelled longer distances in men than women to reach the point that it crossed the clavicle. Our results demonstrated that the subclavian artery does not pass from the inferior margin of the clavicle, thus, superior plate osteosynthesis does not have any risk to injury against the subclavian vessels during the management of the clavicle fractures.

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.

Simulation of RIRS in soft cadavers: a novel training model by the Cadaveric Research On Endourology Training (CRET) Study Group.

PURPOSE: The aim of the current study was to evaluate the use of fresh-frozen concurrently with embalmed cadavers as initial training models for flexible ureteroscopy (fURS) in a group of urologists who were inexperienced in retrograde intrarenal surgery (RIRS). METHODS: Twelve urologists involved in a cadaveric fURS training course were enrolled into this prospective study. All the participants were inexperienced in fURS. Theoretical lectures and step-by-step tips and tricks video presentations on fURS were used to incorporate the technical background of the procedure to the hands-on-training course and to standardize the operating steps of the procedure. An 8-item survey was administered to the participants upon initiation and at the end of the course. RESULTS: Pre- and post-training scores were similar for each question. All the participants successfully completed the hands-on-training tasks. Mean pre-training duration [3.56 ± 2.0 min (range 1.21-7.46)] was significantly higher than mean post-training duration [1.76 ± 1.54 min (range 1.00-6.34)] (p = 0.008). At the end of the day, the trainers checked the integrity of the collecting system both by endoscopy and by fluoroscopy and could not detect any injury of the upper ureteral wall or pelvicalyceal structures. The functionality of the scopes was also checked, and no scope injury (including a reduction in the deflection capacity) was noted. CONCLUSIONS: The fURS simulation training model using soft human cadavers has the unique advantage of perfectly mimicking the living human tissues. This similarity makes this model one of the best if not the perfect simulator for an effective endourologic training.

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.

Redefining the proximal ulna anatomy.

PURPOSE: Complex fractures of the olecranon have always been a difficult condition for treatment. Successful reconstruction depends on restoration of the anatomic contributors to stability. The purpose of this study was to define the proximal ulna anatomy in detail with respect to fracture fixation and arthroscopy. METHODS: In 50 normal adult ulnae (26 left, 24 right); posterior olecranon height (POH), olecranon width (OW), trochlear notch width (TW), the distances between the olecranon and the trochlear notch on radial and ulnar sides (RTH, UTH), and proximal ulnar angulations were measured with a ruler and a digital goniometer. RESULTS: The average POH was 24.6 mm, OW was 23.1 mm, TW was 22.3 mm, RTH was 16.2 mm, and UTH was 15.8 mm. The mean value for proximal ulna torsion angle (PUTA) was found 11.1°. The mean varus angulation was 9.3°. The average articular angle was 27.7° and proximal ulnar dorsal angulation (PUDA) was 8°. CONCLUSIONS: The unique bony architecture of the proximal ulna presents particular difficulties for the implants used in fracture fixation and arthroplasty of the elbow. Knowing the detailed anatomy of the variations of proximal ulna will guide the surgeon to obtain a more reliable length of the olecranon and to offer a safe place for Kirschner wire replacement concerning humero-ulnar joint functionality. In this study, PUTA was also defined. The angle determines the rotation of the proximal ulna and it has a great importance for the movements of the joint. The measured angulations will help the surgeon to design the proper prosthesis for the maintenance of the functions of the elbow joint.

The reproduction accuracy for stereolithographic model of the thyroid gland derived from the visible human dataset.

OBJECTIVE: To investigate reproduction accuracy of the rapid prototyping technique by comparing 3-dimensional computer-aided design (CAD) (virtual) model with stereolithographic (solid) replica of the thyroid gland. METHODS: The Visible Human Dataset was used as the input imaging data. The Surfdriver software package was applied on these images to reconstruct the thyroid gland as 3-dimensional Data Exchange File (DXF) models. These models were post-processed in Cinema 4D and 3D-Doctor software for Virtual Reality Modeling Language (VRML) and Standard Triangulation Language (STL) formats. Stereolithographic replica was manufactured in the rapid prototyping machine using STL format. This study was conducted between June 1-30, 2008 at the Department of Anatomy, Hacettepe University, Ankara, Turkey. An excellent agreement was found in comparing the maximal dimensions of the CAD model of the thyroid gland and the corresponding stereolithographic model. Visual and tactile examination of the thyroid gland model allowed correct depiction of the thyroid gland anatomy. The accuracy of the stereolithographic model was attained by comparing wih the CAD model. RESULTS: Dimensional analysis showed that an average difference between the measurements on the virtual and the solid model was 0.09 mm (p=0.06), ranging from 0.07-0.92 mm. Thyroid volume and surface area were calculated to be 25393.9 mm3 and 8242.8 mm2 using 3D-Doctor software, which were agreement with those obtained from Brunn's formula. CONCLUSION: Stereolithographic biomodeling is a state-of-the-art and reliable method of visualizing anatomoclinical structures and abnormalities.

Differential diagnosis in a professional basketball player with foot pain: is it an avulsion fracture or an os supranaviculare?

The os supranaviculare is an accessory bone located on the dorsal aspect of the talonavicular joint close to the midpoint. This rare incidental skeletal variant has an estimated prevalence of 1%. It may rarely become symptomatic and should not be confused with cortical avulsion fractures of navicular or talar head. We present the case of a 25-year-old professional basketball player with pain on the dorsum of his right foot after twisting his ankle during a regular season match. Magnetic resonance imaging findings of the player's foot represented a flake of bone on the superior part of the talar head. The differential diagnosis and clinical outcome of this unusual case are briefly discussed.

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.

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.

New microvenous anastomosis model for microsurgical training: external jugular vein.

In microsurgical training, the femoral vein is used frequently for a microvenous anastomosis model. But the femoral vein in the rat does not completely simulate the human vein because of its thin wall, fragility, and tendency to collapse. These anatomic characteristics cause some difficulty in carrying out anastomoses in microsurgery training particularly for beginners. The authors propose the external jugular vein of the rat for microsurgical training in microvenous anastomoses. In 10 Wistar rats, the anatomy of the external jugular vein was studied by dissection and histology. Anatomic dissections demonstrate that the external jugular vein has an average diameter of 1.9 mm (range: 1.6 to 2.1 mm) without tendency to collapse. The vein is easily dissected without any accompanying anatomic structure for an average segment of 45 mm, allowing effortless approximator clamp placement. Comparison of its cross section with that of the femoral vein and other previously described models by light microscopy and scanning electron microscopy reveals a larger diameter and much thicker vessel wall with a prominent tunica media and adventitia. Based on the anatomic findings in 20 rats, the external jugular vein was anastomosed with end-to-end standard microsurgical technique using 8-0 (n = 10) and 10-0 (n = 10) nylon sutures. Results indicate a 100 percent patency rate immediately after the anastomosis for the two subgroups and 100 percent and 90 percent patency rates 1 week after the procedure for the 10-0 and 8-0 nylon suture groups, respectively. This model presents some advantages: the vein is easily dissected with the naked eye without using the operating microscope because it is the largest vein among the superficially located veins in the rat, and has a thick vessel wall without tendency to collapse. The operative area allows for training inbilateral microsurgical anastomoses using a single skin incision and is safe from autocannibalization. The model simulates clinical microvenous anastomosis better because of its similarities to human large diameter flap veins.

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.

Change of quadriceps angle values with age and activity.

OBJECTIVE: The lines connecting the anterior superior iliac spine to the center of the patella and the center of the patella to the tibial tuberosity make the quadriceps angle (Q angle), and this can be used as data for patellar alignment. We undertook this study to provide detailed information about the change of Q angle values with age and activity. METHODS: The study was conducted on 474 active (AG) (soccer players) and 765 sedentary (SG) boys (N=1239) from the age of 9-19, and the sedentary group also served as control to their age matched active counterparts. The statistical methods used were the student's t-test and the 3 way analysis of variance (ANOVA). The study was carried out in the laboratories of the Anatomy Departments and School of Physical Education and Sports, Istanbul and Hacettepe Universities between 2001 and 2003. RESULTS: The right and left Q angle values within both groups were statistically insignificant. The comparison of the groups showed a very high level of significant difference between the groups for both knees (AG right Q angle = 14.54 +/- 4.76, SG right Q angle = 17.98 +/- 3.24; AG left Q angle = 14.41 +/- 4.61, SG left Q angle = 18.12 +/- 3.55). The 3 way ANOVA showed that the age and physical activity had equally highly significant effects on Q angle values with a greater change in the active group's values. CONCLUSION: We conclude that 1) children and adolescents have greater Q angle values than adults, 2) a change in quadriceps strength and tone, caused by both growth and activity, results in a decrease of the Q angle and 3) activity, particularly playing soccer in our study, has a remarkable effect on the Q angle.