The ischiatic region: normal and MRI anatomy.

AIM: The aim of this study was to describe the anatomy correlated to the normal magnetic resonance imaging (MRI) images of the proximal thigh region and the ischial tuberosity. METHODS: MRI coronal and axial sequences were obtained from 20 asymptomatic volunteers (10 male and 10 female) aged 20 to 38 years (mean age: 28 years), and then they were compared with 2 anatomical dissections and 7 cryosections of 6 cadaver thighs. RESULTS: The anatomical specimens were directly correlated with MRI scans. From the comparison it could be seen how the axial MRI sequences well outlined the sciatic nerve, usually observed oval in shape with moderate signal intensity, and thus easily detectable from other surrounding organs. Other structures were also identified by axial images: the ischial tuberosity, the proximal origin of the hamstring muscles arising from the ischium and the related bursae, the gluteus maximus and its bursa, the quadratus femoris and its inconstant bursa, a triangular adipose body and vessels. Coronal scans also showed well the hamstring muscles, both in length and thickness. CONCLUSIONS: Both MRI images and cadaver dissections showed the ischial tuberosity as an interesting intersection area that could be delimited as follows: on the dorsal border the gluteus maximus and its bursa, on the dorso-medial side the hamstring muscle origin, and on the antero-lateral side the quadratus femoris muscle with its inconstant bursa and the ischial tuberosity. These anatomical and MRI descriptions are very useful to give a contribution to the right explanation of sciatic symptoms caused by those sports specifically overloading the hamstring muscles. Frequently, in fact, in these athletes a sciatic syndrome arise drawing the physician's attention to the lumbosacral joint or to the sciatic nerve course near the piriformis muscle. Another very important site where the sciatic symptoms can rise, indeed, could also be found in the hamstring muscle region, where the nerve run under the gluteus maximus beside the ischiatic bone. Athletes who manifest notorious muscle overload in this anatomical region usually show sciatic pain symptoms that are not to be related with pathologies of the lumbosacral junction nor to relationships of the sciatic nerve with the piriformis muscle but rather to relationships that this nerve acquires with either gluteal muscles as well as with muscles of the underneath ischiatic region.

Sports injuries in the pelvis and hip: diagnostic imaging.

We discuss the role of imaging techniques in examining the athletes with sports injuries involving the pelvis and the hip. Pelvis and hip pain is of difficult clinical clarification because of the various athletic injuries which may affect the bone or soft tissues at different anatomic sites. Moreover, the symptoms of pelvis and hip injuries are similar in most cases and they are often diffuse and atypical. Diagnostic imaging can play an essential role because treatment success depends on a correct diagnosis and these techniques can actually differentiate the most frequent causes of pelvis and hip sports injuries such as groin strain, osteitis pubis, ischial intersection syndrome, snapping hip, stress fractures, hernias and avulsion fractures. Finally, we discuss the role of magnetic resonance imaging in detecting the causes of hip pain other than sports injuries, such as avascular necrosis, reflex sympathetic dystrophy syndrome, herniation pit, acetabular labrum injuries. To conclude, diagnostic imaging techniques currently permit the direct and noninvasive depiction of pelvis and hip conditions. Particularly, magnetic resonance imaging is very helpful in detecting injury site, extent and characteristics; it can also predict the time period an athlete will be disabled and help define the best treatment planning.

Computed tomography of meniscal cysts of the knee joint.

CT findings of meniscal cysts, without intra-articular contrast medium, were compared with those of arthroscopic surgery in 12 patients. CT clearly defined the type, site and extent of the meniscal cysts. The CT diagnosis was confirmed by surgery in all patients. CT is a simple and accurate method for the diagnosis of meniscal cysts, and facilitates surgical planning.

[Normal and pathologic symphysis pubis: value of imaging]. / Symphyse pubienne normale et pathologique: apport de l'imagerie.

The pubic symphysis is a region which has been little or poorly investigated by imaging. It is however electively and primarily affected by many micro and macro-trauma and is a convenient witness of more general disorders, in particular rheumatological. After a brief anatomical and biomechanical review, the principal pathological aspects are set out.

The axial view in evaluating tibial translation in cases of insufficiency of the posterior cruciate ligament.

The purpose of this report is to present a new radiological method of diagnosis and evaluation of posterior instability using the patellofemoral axial view. During a period of 22 months, we performed clinical and radiological assessments on 20 patients (6 acute and 14 chronic) with isolated posterior instability caused by posterior cruciate ligament (PCL) rupture and on 20 patients with normal knees. The radiological examination included stress radiographs using the Telos device (Telos, Griesheim, Germany) as well as a modification of the routine axial patellofemoral view. Both diagnosis and quantification of the posterior tibial translation was possible in all cases by measuring, on the axial view, the distance between the anterior edge of the tibial plateau and the center of the femoral groove (trochlea). Clinical examination, conventional radiography, KT-1000 arthrometry, stress radiography at 90 degrees and at 20 degrees of flexion, and magnetic resonance imaging all assist in diagnosing a PCL tear. This new radiographic technique is simple, fast, and consistently effective both in patients with acute and those with chronic PCL tears, as well as in those who have undergone PCL reconstruction.

[Groin pain in athletes: role of magnetic resonance]. / La pubalgia negli atleti: ruolo della Risonanza Magnetica.

INTRODUCTION: Aim of our work was to evaluate the diagnostic role and potentials of Magnetic Resonance Imaging (MRI) in the study of groin pain in athletes and in the differential diagnosis among the pathological conditions that cause this syndrome. MATERIAL AND METHODS: MRI examinations were performed with a 1.5 T superconductive magnet, and a 0.2 T permanent magnet. Spin-Echo (SE) T1-w, PD, SE T2-w, Gradient-Echo (GE) T2-w and fat saturation sequences were used, on axial, sagittal and coronal scan planes. We performed MRI on twenty-five athletes (22 men and 3 women; age range 17 to 32 years) with chronic groin pain of questionable origin who had been complaining of it for at least 6 months. In 22 cases, radiographs were available; Computed Tomography (CT) had been performed in 3 cases and Ultrasound (US) in 7 cases. Nine patients were submitted to MRI after the symptoms had disappeared. RESULTS: In all patients, MRI provided an accurate depiction of pubic bone alterations and of adjacent myotendinous structures. In 14 cases, osteitis pubis was diagnosed, which was bilateral in 2 cases only (muscular asymmetry of the rectus abdominis was found in 4 of these patients); 4 patients had myotendinous posttraumatic changes (1 hematoma of the psoas muscle and 3 injuries of the abductor muscles of the thigh); 4 patients presented isolated dysmetria of rectus abdominis muscles, with unilateral involvement of the sacroiliac joint in 1 patient; 3 patients had inguinal hernia, surgically confirmed in all cases. DISCUSSION: Osteitis pubis, intended as reactive intraspongiuos edema of the pubic bones, is the most frequent cause of groin pain in athletes. In the early diagnostic phases, both plain films and CT may be negative or not specific. On the other hand, MRI has always proved to be a valuable diagnostic technique in detecting the osteitic change as an area of low signal intensity on T1-w images and of high and homogeneous signal intensity on T2-w scans without fat suppression. Dysmetria of the straight muscles of the abdomen, which may be associated, is always well depicted by MRI on axial planes. Both posttraumatic and dysmetric changes of the muscular structures adjacent to the pubis are well documented by US and MRI. The latter, however, thanks to its multiplanar capabilities, allows better spatial assessment of the alteration, especially if located at peri-insertional level. Possible associated diseases such as the involvement of the sacroiliac joints are also well shown by MRI. Inguinal hernias are easily demonstrated by MRI, which allows the direct visualization of the hernial sac within the inguinal canal. CONCLUSIONS: In our experience, only MRI can permit an accurate and early diagnosis of the different sport-related pubic conditions. MRI is also a valuable tool in monitoring the alterations with reference to their response to treatment, which may also help bring the athletes back to their activities.

Computed tomography of the knee joint: technique of study and normal anatomy.

Computed tomography was employed in 100 cases to examine the knee joint, without the use of intraarticular contrast medium administration. For greater resolution, only one leg of the patient was introduced into the gantry, and the limb being examined was immobilized and flexed at 8-10 degrees. Computed tomography clearly demonstrated all the anatomical structures that are of clinical interest such as menisci, cruciate and collateral ligaments, and articular and paraarticular soft tissues and tendons. The exact knowledge of the anatomy in axial view and in the indispensable sagittal and coronal reconstructions is fundamental in the identification of pathological conditions.

Computed tomography of the knee joint: clinical results.

Computed tomography (CT) was used to examine the knee joint in 175 patients with various pathological conditions. In 118 of these patients a unique technique of study was employed. This technique is based on thin slices, a high resolution reconstruction program, and routine multiplanar reconstructions, without intraarticular contrast medium administration. In 36 patients studied with this technique, surgery was performed, thus permitting verification of the CT patterns. We concluded that CT may identify lesions of menisci, cruciate and collateral ligaments, and other pathologic conditions with at least 90% accuracy.

CT demonstration of capsuloligamentous lesions of the knee joint.

Direct CT of the knee joint was performed on 45 patients who subsequently underwent surgery for clinically suspected capsuloligamentous lesions. It was possible to perform a complete examination on all patients, even those immobilized in a cast or with acute clinical symptoms. Computed tomography correctly differentiated 32 lesions of the anterior cruciate ligament, five lesions of the posterior cruciate ligament, 16 lesions of the collateral ligaments, and 43 associated meniscal lesions. In five cases surgery disproved the CT diagnosis. Our experience permitted us to identify direct CT signs that not only indicate the presence of a capsuloligamentous lesion but also determine its site, extent, and seriousness.

Meniscal lesions of the knee joint: CT diagnosis.

Computed tomography (CT) resulted in a diagnostic accuracy of 89.2% and 96.1% for medial and lateral meniscal lesions, respectively, in 109 patients who underwent surgery after a direct CT study of the knee joint for a clinically suspected meniscal lesion. The meniscal lesions were the only pathologic condition found in 59 patients, while in 35 patients they were associated with various lesions of the cruciate ligaments (31 cases) and collateral ligaments (15 cases) and with cystic bursitis (6 cases). In the remaining 15 patients, the menisci were normal, but in eight of these cases, lesions of other knee joint structures were present. If meniscal lesions are clinically suspected, direct CT study of the knee joint may be considered the elective radiologic diagnostic method, rather than the more invasive arthrography. It may also be helpful in selecting patients for diagnostic and therapeutic arthroscopy.

Prosthetic reconstruction of the anterior cruciate ligament of the knee: the roles of CT scan and M.R.

The authors examined 10 patients treated by intra-articular reconstruction of the anterior cruciate ligament with an artificial ligament in terylene (Kejo-Leeds type). Clinical evaluation was supplemented by CT scan and magnetic nuclear resonance (M.R.). The basic parameters assessed were the positioning of the tunnels, biological anchoring, presence of reactive synovitis, growth and modification of periligamentous fibrous tissue, characteristics and relationships of the extra-articular plastic. CT scan was better at determining the tunnels, evaluating biological anchoring and visualising the new ligament in its intra-articular course. Magnetic nuclear resonance was better at evaluating changes in the periligamentous tissue. The authors therefore conclude that M.R. is preferable in the early follow-ups, while CT scanning has greater diagnostic value in follow-ups after six months.

[Comparing computerized tomography and magnetic resonance in the study of articular pathology of the knee]. / Raffronto TC e RM nello studio della patologia articolare del ginocchio.

The authors present a comparison between the diagnostic accuracy of computed tomography (CT) and magnetic resonance imaging (MRI) in the articular pathologies of the knee. CT and MRI were performed in 30 patients who subsequently underwent surgery. CT and MRI results were compared on three bases: technique, definition of normal anatomy, and diagnostic accuracy. CT allowed a standardization of the technique, while MRI was superior in defining normal anatomy--especially in the study of capsulo-ligamentous structures. In all cases the use of both CT and MRI allowed a correct diagnosis, showing the site, extent and gravity of the lesion. CT proved to be superior to MRI in 4 cases, while MRI corrected CT diagnosis in 11 cases; in 15 patients both techniques had the same diagnostic accuracy. Meniscal tears were better identified by CT, while MRI was superior in the detection of ligamentous lesions and in the characterization of PVNS and tendinitis of the patellar tendon. In conclusion, MRI should be performed in selected cases only, or when CT cannot be trusted; on the other hand, it might also be used as a first-choice diagnostic procedure for synovial pathologies and acute lesions of the anterior cruciate ligament.

The use of computerized tomography in the study of the cruciate ligaments of the knee.

Computerized tomography was used to investigate the knee joint, without the aid of a contrast medium, in 253 patients referred with a variety of diagnoses. The authors report in particular their experience in the visualization of the cruciate ligaments and assessment of the location, extent and nature of any relative lesions. Computerized tomography proved to be an extremely reliable means of investigating all the capsulo-ligamentous structures, both intra- and extra-articular. The diagnosis was accurate in 94% of cases with disorders of the cruciate ligaments.

[Computerized axial tomography and electromyography in vertebral and spinal cord pathology]. / Tomografia assiale computerizzata ed elettromiografia nella patologia vertebro-midollare.

Fifty patients with lumbar spinal disease, 47 of them with disk herniation, were studied preoperatively using both electromyography and computerized tomography (CT), in order to verify the mutual diagnostic significance and accuracy of these techniques. Electromyographic studies provided correct informations regarding the level of the lesion in 41 patients with 1 mistaken level and 8 false negatives, without indicating the nature of involved pathologies. The specific nature of the lesions was correctly indicated by CT studies in 43 patients with 4 incorrect diagnoses and 3 false negatives, without defining the functional loss produced by the lesions. Using electromyography and CT together, first electromyographic studies to establish the spinal level to investigate principally with CT, the diagnostic accuracy can improve because of the decrease of the false negatives.

Clinical interpretation of cysts in the popliteal space using computerised tomography.

The use of computerised tomography in the examination of the knee joint has made it possible to investigate popliteal cysts much more precisely, particularly as regards incidence, localisation, size, shape and above all their possible relationship with other pathological conditions. In 315 examinations, 60 patients (19.5%) were found to have cysts in the popliteal space of whom only 9 were unassociated with any other pathology of the knee. Fifty-five (91.6%) of these cystic dilatations were semimembranosus bursae. The two pathogenetic theories which are favoured at the moment were considered in the light of our findings, but it appears from our experimental work that both could be valid.