The benefit of SPECT/CT in the diagnosis of osteochondral lesions of knee joints

Summary

Introduction:

The bone scintigraphy and other more complex examinations are recomended for patients with knee joints damage, whose symptoms do not match findings of simpler imaging methods (especially based on radiographs) and laboratory methods.

Purpose:

The aim of the study was to evaluate the benefit of SPECT/CT examination in the diagnosis of avascular necrosis, osteochondrosis dissecans and other osteochondral lesions of knee joints. To compare the main clinical findings, X-ray findings and results of SPECT/CT. To assess the benefits of the availability of the hybrid system in routine practice.

Materials and methods:

The data of 38 patients, with 45 affected joints from the years 2007–2017 (mean age 60 ± 17 years, 57 % of women) who underwent bone scintigraphy with regional SPECT and separately CT until 2014, then with hybrid SPECT/CT, were retrospectively evaluated.

Results:

Pain (87 %) and swelling of the knee (21 %), pain in hips and spine (13 %) dominated in clinical findings. Secondary diagnosis was gonartrosis in 58 %, trauma in 16 %, prostate cancer or breast cancer in 16 %. Radiography was suspected in 36 % only before SPECT examination. Bone scintigraphy was positive in 96 % of cases. A blood pool was positive in 80 % of cases. According to CT results we found an osteochondral defect in 67 %, osteochondrosis dissecans in 20 %. We observed early stage of the joint damage in 9 % and early condyle osteonecrosis in 4 %. The number of discovered pathological findings increased to six times after the introduction of the SPECT/CT hybrid system into clinical routine practice.

Conclusions:

Early condyle osteonecrosis, osteochondrosis dissecans, osteochondral defect and the „atypical“ degenerative changes of the knee joints based on only clinical symptomatology or radiography cannot be distinguished. Hybrid SPECT/CT is an appropriate investigative method for these diagnoses. It improves patient management and treatment planning.

Key Words:

knee, SPECT/CT, chondral lesion, osteonecrosis