Indium Scan (Indium-Oxine Scan):

It is a scanning procedure used to evaluate pooling of white blood cells at a site of inflammation or infection, requiring that a patient's white blood cells (leukocytes) are first labeled (the cells are marked or identified) with a radioactive pharmaceutical substance called Indium (Indium-Oxine, In-111).  A scan is performed to track the migration pattern and locate white blood cells at the site of possible infection, inflammation or abscess.  By labeling the leukocytes, radiologists or nuclear medicine specialists can then watch the movement pattern on WBCs.

To perform the “taggingâ€? procedure a nuclear medicine technologist draws about 50 ml. of blood.  White blood cells are collected and exposed to Indium, then re-injected through an IV back into the patient.  The Indium scan is scheduled about 24 hours after the leukocytes (WBCs) have been labeled with the Indium.  Occasionally scanning may be scheduled 48 hours after labeling.  The scan procedure requires that the patient lie on a special scanning table.

The Indium study may be used to rule out an infection within the vertebral body, the spinal canal (an intradural or epidural abscess), the spinal (facet) joints and/or the intervertebral disc.  There has recently been some concern about the utility of labeled leukocytes in the evaluation of musculoskeletal infection.  The imaging of tagged leukocytes may occasionally miss an infection within the spine (osteomyelitis) for reasons that are not well understood.  One theory is that cell clumping can occur and produce local accumulation of radioactivity in tissues.  These areas may not “wash outâ€? in 24 hours and thus be one of the reasons for false positive results.  Such problems can be reduced by imaging immediately after injection.  The study may be used to rule out infection, post-operative infection and inflammatory processes of the spine. 

Isokinetic Testing:

Isokinetic testing is used to objectively evaluate nerve and related muscle function.  It also allows for evaluation of joints.  To perform a study, the patient is positioned on specialized equipment so that the specific body and joint movements to be measured are isolated.  The equipment is set at different speeds and the force applied is measured throughout the range of movement.  The results are recorded at different speeds so that a speed/strength/power relationship can be seen.  Comparative evaluation of muscle strength with side-to-side assessment and of agonists/antagonists relationships can be performed.  The equipment is often large, bulky and expensive; therefore, these tests are often performed at large clinics and in university settings as part of research projects, or as part of injury rehabilitation services.

Isokinetic testing can be used to evaluate impairment of muscle function secondary to central or peripheral nerve compromise, including spinal nerve root compromise.  Isokinetic testing may be performed as part of a battery of functional tests in the individual with neurological compromise.  Isokinectic testing provides an extensive array of quantitative data of which can be used to baseline physical performance.  It can also be used to help assess neurological and neuromuscular recovery.