Quantitative bone single-photon emission CT/CT parameters reflect pain and functional status of symptomatic basal joint arthritis of the thumb.
AIMS
The aim of this study was to assess arthritis of the basal joint of the thumb quantitatively using bone single-photon emission CT/CT (SPECT/CT) and evaluate its relationship with patients' pain and function.


METHODS
We retrospectively reviewed 30 patients (53 hands) with symptomatic basal joint arthritis of the thumb between April 2019 and March 2020. Visual analogue scale (VAS) scores for pain, grip strength, and pinch power of both hands and Patient-Rated Wrist/Hand Evaluation (PRWHE) scores were recorded for all patients. Basal joint arthritis was classified according to the modified Eaton-Glickel stage using routine radiographs and the CT scans of SPECT/CT, respectively. The maximum standardized uptake value (SUVmax) from SPECT/CT was measured in the four peritrapezial joints and the highest uptake was used for analysis.


RESULTS
According to Eaton-Glickel classification, 11, 17, 17, and eight hands were stage 0 to I, II, III, and IV, respectively. The interobserver reliability for determining the stage of arthritis was moderate for radiographs (k = 0.41) and substantial for CT scans (k = 0.67). In a binary categorical analysis using SUVmax, pain (p < 0.001) and PRWHE scores (p = 0.004) were significantly higher in hands with higher SUVmax. Using multivariate linear regression to estimate the pain VAS, only SUVmax (B 0.172 (95% confidence interval (CI) 0.065 to 0.279; p = 0.002) showed a significant association. Estimating the variation of PRWHE scores using the same model, only SUVmax (B 1.378 (95% CI, 0.082 to 2.674); p = 0.038) showed a significant association.


CONCLUSION
The CT scans of SPECT/CT provided better interobserver reliability than routine radiographs for evaluating the severity of arthritis. A higher SUVmax in SPECT/CT was associated with more pain and functional disabilities of basal joint arthritis of the thumb. This approach could be used to complement radiographs for the evaluation of patients with this condition. Cite this article: Bone Joint J 2021;103-B(8):1380-1385.
['Kim|Yong-Il|YI|https://orcid.org/0000-0002-4113-8351', 'Ryu|Jin-Sook|JS|', 'Kim|Jae Kwang|JK|https://orcid.org/0000-0001-5104-4634', 'Al-Dhafer|Bassmh Abdullah A|BAA|', 'Shin|Young Ho|YH|']
D000368:Aged D018771:Arthralgia D001168:Arthritis D052737:Carpometacarpal Joints D005260:Female D000085542:Functional Status D006801:Humans D008297:Male D008875:Middle Aged D010147:Pain Measurement D012189:Retrospective Studies D000072098:Single Photon Emission Computed Tomography Computed Tomography
Arthritis SPECT/CT Thumb basal joint