Elsevier

Seminars in Nuclear Medicine

Volume 39, Issue 5, September 2009, Pages 293-307
Seminars in Nuclear Medicine

SPECT/CT Imaging in General Orthopedic Practice

https://doi.org/10.1053/j.semnuclmed.2009.06.002Get rights and content

The availability of hybrid devices that combine the latest single-photon emission computed tomography (SPECT) imaging technology with multislice computed tomography (CT) scanning has allowed us to detect subtle, nonspecific abnormalities on bone scans and interpret them as specific focal areas of pathology. Abnormalities in the spine can be separated into those caused by pars fractures, facet joint arthritis, or osteophyte formation on vertebral bodies. Compression fractures can be distinguished from severe degenerative disease, both of which can cause intense activity across the spine on either planar or SPECT imaging. Localizing activity in patients who have had spinal fusion can provide tremendous insight into the causes of therapeutic failures. Infections of the spine now can be diagnosed with gallium SPECT/CT, despite the fact that gallium has long been abandoned because of its failure to detect spine infection on either planar or SPECT imaging. Small focal abnormalities in the feet and ankles can be localized well enough to make specific orthopedic diagnoses on the basis of their location. Moreover, when radiographic imaging provides equivocal or inadequate information, SPECT/CT can provide a road map for further diagnostic studies and has been invaluable in planning surgery. Our ability to localize activity within a bone or at an articular surface has allowed us to distinguish between fractures and joint disease. Increased activity associated with congenital anomalies, such as tarsal coalition and Bertolotti's syndrome have allowed us to understand the pathophysiology of these conditions, to confirm them as the cause of the patient's symptoms, and to provide information that is useful in determining appropriate clinical management. As our experience broadens, SPECT/CT will undoubtedly become an important tool in the evaluation and management of a wider variety of orthopedic patients.

Section snippets

Back Pain in Preteens and Teenagers

The intensity of athletic competition in the preteen and teenage years has led to a large number of injuries that result in back pain, a situation made worse by the heavy backpacks that students carry to and from school. Because many injuries in this age group are as a result of muscle strain, physical therapy and abstaining from competition are often prescribed; in patients with fractures of the pars interarticularis, physical therapy needs to be avoided and back braces are often used to limit

Bertolotti's Syndrome

Figure 4 shows a patient who presented with low back pain. The planar bone scan shows only faint activity on the right side of the lumbar spine, but SPECT shows a more prominent focal abnormality. The location of the uptake was unclear until fusion imaging showed that the activity was in an articulation between the transverse process of L5 and the sacrum, an abnormality described in the early 1900s by an Italian physician named Mario Bertolotti.7 He suggested that the rigidity of the L5-S1

Pain After Spinal Fusion

Patients with intractable low back pain or those with significant neurologic deficit may undergo spinal fusion to stabilize the spine, restricting motion to prevent symptoms. A significant number of patients will have either residual or recurrent pain and further treatment depends on distinguishing among several possible causes.9 There may be failure of the surgical hardware, which usually is associated with fracture of the bone graft and formation of a pseudarthrosis. In this setting, CT

Foot and Ankle

Perhaps the greatest effect of SPECT/CT on our bone scan patients is in the foot and ankle. In our experience, stress fractures of the metatarsals or sesamoiditis can usually be identified with a single plantar image, but in many cases, the location of the activity may not be obvious from planar imaging. It is critical to patient management that we are able to distinguish between stress fractures of the mid foot, degenerative joint disease in the mid foot and hind foot, and osteochondritis

OCD

OCD is a repetitive stress injury seen in young athletes.11 Overuse of a joint leads to disruption in the blood supply to the adjacent bone. Bone and cartilage fragments often separate because of devitalization of the subarticular region and these fragments may cause severe pain in the joint. Although the condition has been described in the knee, hip, and elbow, our experience to date has been limited to the ankle. The patients present with vague ankle pain, and most often have no recollection

Tarsal Coalition

Tarsal coalition is a condition in which there is congenital fusion of two of the tarsal bones with either a bony or fibrous bridge.12 These abnormal connections cause abnormal stress on the hind foot, with pain usually beginning in the early teenage years. Surgery is required to separate the bones in those patients who do not respond to conservative treatment.

A 27-year-old female runner presented with pain in the left mid foot and was sent for a bone scan to find her presumed metatarsal stress

Osteoid Osteoma

Osteoid osteomas are benign tumors of bone seen often in teenagers.13 They classically produce nocturnal pain that responds dramatically to salicylates. The pain responds to surgical removal of the nidus. Recently, radiofrequency ablation has also been used successfully.

A focus of intense activity is almost always seen on bone scan and a lucent nidus can usually be identified on CT, but the findings can be difficult to interpret when they occur in the small bones of the mid foot.

A man in his

Spine

Although the nuclear medicine published data suggest that gallium and WBC imaging of the spine are ineffective in finding infections, we suspect that the poor performance may be due in part to our inability to localize gallium uptake and distinguish normal bone uptake from infection.14 Again, dual isotope SPECT/CT may provide some help.

A 68-year-old man had back pain and his MRI suggested osteomyelitis and/or diskitis at the L4-L5 level. Aspiration of the L4-L5 disk space yielded no organisms.

Conclusion

SPECT/CT has rekindled interest in the use of Nuclear Medicine studies among our orthopedists. Of particular value to them is our ability to help localize pathology and plan surgical intervention. As our experience grows, we expect to be able to expand the range of appropriate clinical indications for SPECT/CT. To accomplish this goal, we need to work with orthopedists to update our understanding of the issues involved in evaluating and treating orthopedic patients and re-educate them in the

References (14)

  • P. Matin

    Basic principles of nuclear medicine techniques for detection and evaluation of trauma and sports medicine injuries

    Semin Nucl Med

    (1988)
  • P. Matin

    The appearance of bone scans following fractures, including immediate and long-term studies

    J Nucl Med

    (1979)
  • R.D. Bellah et al.

    Low back pain in adolescent athletes: Detection of stress injury to the pars interarticularis with SPECT

    Radiology

    (1991)
  • J.O. Lusins et al.

    Bone SPECT in patients with persistent back pain after lumbar spine surgery

    J Nucl Med

    (1989)
  • R.J. Bodner et al.

    The use of single photon emission computed tomography (SPECT) in the diagnosis of low-back pain in young patients

    Spine

    (1988)
  • A.D. Elster

    Bertolotti's syndrome revisitedTransitional vertebrae of the lumbar spine

    Spine

    (1989)
  • M. Bertolotti

    Contributo alla conoscenza dei vizi di differenzazione regionale del rachide con speciale riguardo all' assimiliazione sacrale della V lombare

    Radiol Med (Torino)

    (1917)
There are more references available in the full text version of this article.

Cited by (0)

View full text
Copyright © 2009 Elsevier Inc. All rights reserved.