Clayton Frater

Radionuclide Bone Scintigraphy in Sports Injuries

Bone scintigraphy is one of the mainstays of molecular imaging. It has retained its relevance in the imaging of acute and chronic trauma and sporting injuries in particular. The basic reasons for its longevity are the high lesional conspicuity and technological changes in gamma camera design. The implementation of hybrid imaging devices with computed tomography scanners colocated with the gamma camera has revolutionized the technique by allowing a host of improvements in spatial resolution and anatomical registration. Both bone and soft-tissue lesions can be visualized and identified with greater and more convincing accuracy. The additional benefit of detecting injury before anatomical changes in high-level athletes has cost and performance advantages over other imaging modalities. The applications of the new imaging techniques will be illustrated in the setting of bone and soft-tissue trauma arising from sporting injuries.

A novel view for the scintigraphic assessment of the elbow

Using any imaging modality, the elbow is a complex joint to evaluate. The use of scintigraphy in the evaluation of the effects of acute or chronic trauma has largely been confined to epicondylitis. We developed a skyline view of the elbow that minimized the effect of overlap and assessed its incremental value in the scintigraphic assessment of several pathological conditions. Thirty-four abnormalities were evaluated in 20 patients with a range of pathologies, including epicondylitis, ligamentous avulsion injury, articular injury, fractures and synovitis. The incremental value of addition of the skyline view to the standard views was assessed in addition to the overall accuracy of scintigraphy. Overall, scintigraphy detected 27 of 34 abnormalities, with the standard views of the elbow accurately identifying 15 and the skyline view 23 abnormalities. This gave the skyline view an incremental value of 24% over the standard views. In conclusion, scintigraphy has the potential to identify a greater range of pathologies in the elbow than previously reported, due to the addition of the skyline view to the standard views.

Prominence of the C2 vertebra on SPECT: a normal variant

Mild preferential focal uptake of Tc-99m HDP in the spinous process of C2 was identified with SPECT of the cervical spine performed in patients in whom the indication for bone scintigraphy was suspected of lesions in the limbs. Its presence in all 21 subjects indicates that such uptake is a normal finding.

Lung perfusion and chest wall configuration is altered by glossopharyngeal breathing

Glossopharyngeal insufflation is used by competitive breath-hold divers to increase lung gas content above baseline total lung capacity (TLC) in order improve performance. Whilst glossopharyngeal insufflation is known to induce hypotension and tachycardia, little is known about the effects on the pulmonary circulation and structural integrity of the thorax. Six male breath-hold divers were studied. Exhaled lung volumes were measured before and after glossopharyngeal insufflation. On two study days, subjects were studied in the supine position at baseline TLC and after maximal glossopharyngeal insufflation above TLC. Tc 99m labelled macro-aggregated albumin was injected and a computed tomography (CT) scan of the thorax was performed during breath-hold. Single photon emission CT images determined flow and regional deposition. Registered CT images determined change in the volume of the thorax. CT and perfusion comparisons were possible in four subjects. Lung perfusion was markedly diminished in areas of expanded lung. 69% of the increase in expired lung volume was via thoracic expansion with a caudal displacement of the diaphragm. One subject who was not proficient at glossopharyngeal insufflation had no change in CT appearance or lung perfusion. We have demonstrated areas of hyperexpanded, under perfused lung created by glossopharyngeal insufflation above TLC.

TI-201 scintigraphy in muscle trauma.

Muscle uptake of Tl-201 thallous chloride in the larger or more major groups, particularly the legs, chest, and upper limb areas, is not uncommonly observed in healthy persons. However, as illustrated in three patients, such uptake, when localized or asymmetric, may provide evidence of unrecognized traumatized muscle, resulting from more chronic or subacute muscle overuse than the acute muscle insult that produces the marked uptake of Tc-99m phosphates associated with frank rhabdomyolysis.

Blunt trauma soft-tissue uptake on skeletal scintigraphy

Muscle and soft-tissue uptake have been described numerous times in the literature in patients undergoing Tc-99m methylene diphosphonate skeletal scintigraphy following trauma. Many of these traumas range from electrical burns, intramuscular injections, sports-related trauma, and overexercising, to actual physical damage resulting in superficial bruising and skin discoloration. In this case the patient presented with continuing low back pain after falling down some stairs. Although the scan was essentially normal for bony trauma, subtle soft-tissue uptake was detected that was enhanced with the addition of single photon emission computed tomographic imaging and surface rendering.

Development of osteoradionecrosis demonstrated on bone scintigraphy.

&NA; A 62‐year‐old woman was examined because of chronic groin pain indicative of possible symphysitis pubis. She had a total hysterectomy 2.5 years earlier for squamous cell carcinoma of the cervix and underwent postoperative radiotherapy. A whole‐body bone scan performed 1 year later revealed a sacral insufficiency fracture with instability reaction in the left sacroiliac joint but no evidence of bony metastatic disease or abnormal uptake in the symphysis pubis. The current whole‐body bone scan did not show evidence of bony metastatic disease but did reveal marked focal osteoblastic activity and hypervascularity within the symphysis pubis in keeping with active osteitis pubis. A pelvic radiograph confirmed the typical radiographic features of radiation‐induced osteitis pubis.

Specific muscle uptake on bone scintigraphy after strenuous activity.

A 38-year-old woman was referred for bone scintigraphy to evaluate her left groin pain, which had been present for a number of weeks. While dynamic and blood pool images were unremarkable, static images at 2 hours demonstrated soft tissue tracer uptake in the proximal thigh muscles medially, corresponding to the adductor longus muscles of both thighs, more so on the left. While the presence of muscle uptake on bone scintigraphy has been well documented after over-strenuous activities, this case demonstrates an unusual selective uptake pattern involving the adductor thigh muscles, the specific groups subject to overuse in the patients recent intensive horse-riding.

Scintigraphy of an avulsion injury of the sartorius insertion in the pelvis.

A 16-year-old athletic boy was examined for a 1-month history of pain in the anterior aspect of the left iliac crest. He was a middle-distance runner who ran regular 400-and 800-meter races. He had no history of direct trauma to the pelvis. The results of plain radiography were reported as normal. Bone scintigraphy showed hyperemia and increased uptake in the left anterior superior iliac crest, at the site of insertion of the sartorius muscle. This was confirmed on ultrasound. Although there are reports of injuries to both the proximal and distal insertions of the sartorius muscle, a Medline search failed to identify any specific cases in the scintigraphic literature.

Coincidental finding of crossed fused renal ectopia detected on bone scintigraphy.

A 26-year-old man was examined for long-standing back pain, with a provisional diagnosis of sacroilitis or ankylosing spondylitis. A limited bone scan with SPECT was performed 2.5 hours after injection. Although the results were essentially normal, the right pelvic kidney was seen on both blood-pool images and delayed images, but the left kidney was seemingly absent. The patient noted that, after a sports-related trauma to the abdomen 10 years before, an intravenous urogram at the time showed a cross fused renal ectopia lying in the right iliac fossa, with two normal pelvicalyceal systems. Subsequently, the patient was advised to discontinue participating in contact sports.