Single photon emission computerized tomography and reverse gantry computerized tomography findings in patients with back pain investigated for spondylolysis.

BACKGROUND

Athletes with low back pain may have sustained a bone stress injury in the lumbar neural arch, including spondylolysis. Single photon emission computerized tomography (SPECT) and reverse gantry computerized tomography (rg-CT) help localize bone stress response and spondylolyses.

OBJECTIVE

To describe the SPECT and rg-CT findings in those patients suspected of suffering from a spondylolysis.

METHODS

Large retrospective case series.

METHODS

Secondary and tertiary care center in England.

METHODS

A total of 213 patients presenting to the Spinal Unit and Sports Medicine Clinics between 1995 and 2000 with low back pain and subsequently investigated for spondylolysis by SPECT and rg-CT.

METHODS

An experienced consultant musculoskeletal radiologist reported the SPECT and rg-CT, and these results along with data from the patient's medical records were analyzed.

METHODS

Sites and sides of increased scintigraphic activity in the lumbar neural arch seen on SPECT and complete and incomplete spondylolyses were recorded.

RESULTS

Single photon emission computerized tomography scan showed increased scintigraphic uptake in 145 patients, mostly (42.3%) at L5. Marked increase in scintigraphic uptake was noted on the left side of the neural arch in 31 patients and on the right in 17 (chi; P < 0.05). Spondylolysis was identified on rg-CT in 81 patients. Spondylolyses were bilateral on 44 occasions, but unilateral lesions occurred in the left pars 36 times and on the right 16 times (chi; P < 0.01)

CONCLUSIONS

Spondylolyses were a frequent finding on rg-CT in young athletes with low back pain. The sports most commonly associated with this stress response in the pars interarticularis were cricket and soccer. The lower lumbar levels are more likely to show abnormalities on SPECT and computerized tomography. Among those investigated for spondylolysis, left-sided lower lumbar pain was more common than right, and a marked increase in scintigraphic uptake was noted on the left more often than the right. Although bilateral spondylolyses were common, left-sided spondylolyses were more common than right. The asymmetric repetitive movements of certain sports may be responsible. In particular, fast bowlers developed spondylolysis on the opposite side of the body to their bowling arm.