Abstract
Background SPECT-CT highlights metabolic activity within skeletal structures, including degenerative arthropathies and other potentially pain-producing abnormalities.
Objectives Investigate the effectiveness of single-photon emission computed tomography (SPECT-CT) in identifying pain generators and assess its role in clinical and surgical decision-making and planning.
Methods Prospective study of 110 patients presenting with neck and back pain. SPECT-CT was ordered to identify pain generators and/or guide surgical planning. Pre– and post–SPECT-CT surveys were obtained to assess pain generator identification and subsequent changes to treatment recommendations.
Results SPECT-CT demonstrated increased uptake in areas corresponding to clinical symptoms in 78.1% of patients. This increased diagnostic specificity reduced the number of diagnostic possibilities per patient and led to a changed diagnosis in 68.1% of patients and a changed treatment plan in 62.7%. The nonoperative group was more likely to have specific, identified targets for injections after SPECT-CT. In 57.7% of surgical candidates, the surgical plan was altered, with 11 patients (42.3%) receiving surgical treatment recommendations involving fewer surgical levels and 4 (15.3%) involving more surgical levels.
Conclusions SPECT-CT appears to be a valuable diagnostic tool in assessing neck and back pain. It may help identify pain generators and limit the need for further diagnostic workup. It was impactful in guiding treatment strategies and potentially improved surgical planning by specifically targeting the affected areas. Further research is needed to validate these findings and establish clinical guidelines for their use in patients with neck and back pain.
Level of Evidence 4.
- SPECT-CT imaging
- lumbar spondylosis
- low back pain
- cervical spondylosis
- neck pain
- pain generators
- diagnostic imaging
- treatment decision-making
Introduction
Axial spine pain is a pervasive health issue that significantly impacts the quality of life and imposes substantial socioeconomic burdens. These symptoms are commonly attributed to underlying cervical or lumbar spondylosis, but managing these conditions effectively remains a significant clinical challenge given the limitations in determining the underlying etiology with typical imaging modalities. Successful treatment often requires advanced diagnostic techniques for diagnosis and treatment. Traditional imaging modalities, including radiographs and magnetic resonance imaging (MRI), are commonly used in the clinical evaluation of this patient population. However, these techniques have limitations, especially in patients with multilevel degenerative disease, and can reveal abnormalities that are not necessarily symptomatic or irrelevant to the underlying pain generator (PG), leading to potential misdiagnosis.1 Although detailed patient history and careful physical examination can suggest potential PGs, MRI is often unable to identify the specific source.2 Discograms and other invasive procedures have been used to potentially identify relevant PGs in the axial spine; however, discography has been associated with a significant risk of normal segment degeneration and has historically had high false positive rates.3
Single-photon emission computed tomography combined with low-dose computed tomography (SPECT-CT) is a hybrid nuclear medicine study that typically utilizes technetium 99m-methyl diphosphate or other radionuclide tracers. When combined with traditional computed tomography (CT), a 3-dimensional representation of increased bony metabolic activity can be obtained, providing anatomic specificity to the diagnostic picture4 (Figure 1). There has been a wide range of described indications for SPECT-CT in the musculoskeletal literature, including evaluation of bony lesions, metastases, infections, and nonunions.2,5–10 Delineating the primary PG in patients with axial back and neck pain has historically been problematic, and the use of SPECT-CT to better identify primary PGs has been described.11–16 In recent years, the use of this imaging technology for the localization of spine pain has increased substantially.
A 64-year-old woman presented with neck pain of unclear etiology after initial evaluation with radiographs and cervical magnetic resonance imaging. Single-photon emission computed tomography combined with low-dose computed tomography demonstrated increased uptake in the left C2–C3 facet joint, and her pain improved significantly following a medial branch block at that location.
While the use of SPECT-CT has been implicated as a potential adjunct for preoperative planning in spinal surgery,17 there is a lack of understanding in the literature regarding whether this nuclear medicine study holds true potential to directly affect management and surgical decision-making among spine surgeons. Furthermore, the potential link between metabolic activity seen on SPECT-CT and pain is not well understood.
Understanding how SPECT-CT might influence management decisions could have significant implications on treatment strategies, including the use and location of surgery, or alternative therapeutic pathways. Differential impact on therapeutic decisions through the use of SPECT-CT may have important ramifications on overall treatment invasiveness, risk, and cost. The objective of this study was to investigate the effectiveness of SPECT-CT imaging in identifying underlying pathologies and possible PGs in patients with axial spine pain and to assess its role in clinical and surgical decision-making. We hypothesized that SPECT-CT would play a significant role in treatment recommendations for patients with axial spine pain when compared with traditional imaging modalities alone.
Methods
This prospective study included patients who presented for evaluation of symptomatic neck and back pain in a single center with 5 spine surgeons between June 2023 and July 2024 and who underwent SPECT-CT as part of their evaluation. Ethical approval for the study was obtained from our institution’s Institutional Review Board (IRB; #13–6297). We retrospectively analyzed clinical data that had been prospectively collected as part of routine clinical care. Since the clinical data used for this study were collected during routine patient care and no experimental procedures were conducted, the need for individual patient informed consent was waived by our IRB. SPECT-CT imaging was ordered at the discretion of each surgeon when traditional imaging, such as radiography and MRI, failed to provide a clear picture of a PG or to limit the scope of treatment (Figure 2). SPECT-CT was primarily ordered to evaluate for more specific therapeutic targets in patients with diffuse spondylosis or multifactorial presentation, or when trying to perform more targeted surgical procedures to avoid larger deformity surgeries.
Schematic representation of the diagnostic process incorporating single-photon emission computed tomography combined with a low-dose computed tomography (SPECT-CT). AP, anteroposterior; MRI, magenetic resonance imaging; NSAIDs, nonsteroidal anti-inflammatory drugs; PT, physical therapy.
When ordered, a discussion of applicable risks, benefits, and alternatives was held with each patient. Pre– and post–SPECT-CT questionnaires were completed by the ordering spine surgeon for each patient. The surveys were utilized to determine the surgeon’s hypothesis as to the source of pain and treatment plan, both before and after the SPECT-CT was complete. The data for this study were collected under our IRB for the collection of patient outcomes.
Data on patient demographics, the rationale for obtaining SPECT-CT, SPECT-CT imaging findings, and changes to treatment recommendations were collected and analyzed. The treatment recommendations from before and after SPECT-CT were compared using χ 2 tests, and the number of recommendations per patient was compared using 2-tailed student t tests to evaluate statistical significance and to determine clinical utility.
Results
A total of 110 patients, 49% men and 51% women, with an average age of 64.6 years, were included. Thirty-two patients (29.1%) had axial neck pain, and 73 (66.3%) had back pain, while 5 (4.5%) had both. The SPECT-CT was ordered to help identify a PG (n = 100), to aid in determining surgical levels (SL, n = 26), or both (n = 16). SPECT-CT demonstrated increased uptake in areas corresponding to clinical symptoms in 78.1% of patients (n = 84). These SPECT-CT results significantly increased diagnostic specificity, with 53 (49%) of patients having ≥2 diagnostic possibilities considered before SPECT-CT, and only 36 (33%) having ≥2 potential sources of pain determined after SPECT-CT (P = 0.022). There was a change in presumed diagnosis in 75 PG patients (68.1%; Figure 3), and the original treatment plan was altered in 69 patients (62.7%) after SPECT-CT. There was significantly increased specificity of nonoperative treatment recommendations with an mean of 1.03 (0.46 SD) treatment recommendations after SPECT-CT, compared with an average of 1.3 (0.59 SD) before SPECT-CT (P = 0.008; Figure 4). This significant decrease largely stemmed from a reduction in additional imaging or further diagnostic workup (49% before SPECT-CT vs 3.6% after SPECT-CT).
Diagnosis and etiology of pain. Figure 3 shows the changes to the frequency of different diagnoses before and after single-photon emission computed tomography combined with a low-dose computed tomography (SPECT-CT) results. There was an overall significant decrease in the number of diagnoses listed, indicating increased diagnostic clarity, specificity, and confidence with respect to the identification of pain generators.
Nonoperative treatment recommendation. Figure 4 demonstrates changes to the treatment plan before and after single-photon emission computed tomography combined with a low-dose computed tomography (SPECT-CT) results. Significantly more patients were sent for specific injections at targeted pathology, and fewer patients required additional diagnostic evaluation. PT, physical therapy.
PG patients were more likely to receive targeted injections following acquisition of SPECT-CT (36 patients after vs 23 before, P < 0.001), less likely to require further diagnostic workup or imaging (2 patients after vs 35 before), and less likely to receive pain management referrals (17 patients after vs 23 before). There were no differences in the rate of pain management referrals before (n = 23) vs after (n = 17) SPECT-CT imaging. Similarly, there were also no differences in the rate of physical therapy referrals before (n = 7) vs after (n = 5).
There was a significant increase in the number of patients who received surgical treatment recommendations after SPECT-CT (49%) compared with before SPECT-CT (35%; P = 0.04). In the SL group, the surgical plan changed in 15 patients (57.7%), with 11 patients (42.3%) receiving surgical treatment recommendations involving fewer SLs and 4 (15.3%, P = 0.19) involving more SLs.
Discussion
The use of SPECT-CT for the diagnostic evaluation of patients presenting with axial spine pain resulted in significant changes in both diagnosis and treatment within our cohort. Most patients had multiple differential diagnoses before undergoing SPECT-CT, and more specific PGs were identified in a substantial majority of those patients. Utilizing SPECT-CT after traditional imaging that did not adequately define a specific PG led to a change in the presumed source of pain in 68% of PG patients and a change in the treatment plan for 62% of patients. There was also a decrease in the number of differential diagnoses considered after obtaining the SPECT-CT scan, which ultimately changed surgeon decision-making for patients who previously had nonspecific axial neck and low back pain.
In patients who received nonoperative treatment recommendations, SPECT-CT was valuable at isolating a pathology thought to be the underlying PG and allowed for significantly more specific treatment recommendations. These patients were more likely to be sent for a specific, therapeutic injection targeted to that pathology, such as a level-specific facet joint, and less likely to receive pain management referrals, which are somewhat generic at our institution and frequently used as a less-favorable attempt at symptomatic control when a specific target cannot be identified. Additionally, the SPECT-CT results were helpful in decreasing additional diagnostic workup, which may further indicate diagnostic clarity or be viewed as a proxy for confidence in the treatment plan. This could potentially lead to significant cost savings as well as secondary risk reduction by avoiding unnecessary testing and procedures, though further research is required.
The SLs group also showed interesting results. Notably, the SPECT-CT findings were associated with a change in the surgical plan in more than half of the patients, thus directly impacting surgical decision-making. This included conversion to a more selective surgery involving fewer levels in 11 patients and larger surgery involving more levels in only 4 patients. SPECT-CT may therefore provide guidance on more selective fusions when managing primary axial spine pain surgically.
Prior literature has supported the concept that the use of SPECT-CT results in identifying PGs, thus subsequently facilitating more targeted interventions. For example, Lee et al retrospectively reviewed 175 patients with chronic low back pain who underwent SPECT-CT/CT during workup and analyzed their numeric rating scale pain scores in response to targeted injection therapy based on scan findings. They found a higher rate of response in patients with active lesions found on SPECT-CT (79.4%) compared with those who did not (63%), lending credibility to the utility of SPECT-CT in identifying PGs.18 Brusko et al described SPECT-CT as a surgical planning tool in their retrospective review of 23 patients with axial neck and back pain who had evidence of hypermetabolic foci and underwent surgery on active levels (primarily lumbar interbody fusion or anterior cervical discectomy and fusion). Eleven patients (47.8%) reported complete symptom resolution at the 6-month follow-up visit. At 1 year postoperatively, 19 patients (82.6%) reported significant relief of their symptoms following surgery.17 The study, however, lacked a comparative cohort of patients without a SPECT-CT/CT obtained prior to surgery. Tender et al retrospectively reviewed 315 patients who underwent diagnostic SPECT-CT/CT and subsequently 48 patients among them who underwent either cervical or lumbar fusion.14 Axial spine pain visual analog scores at 6 months postoperatively improved from 9.04 ± 1.4 to 4.34 ± 2.3 (P = 0.026), with cervical fusion patients improving from 8.8 ± 1.8 to 3.92 ± 2.2 (P = 0.019) and lumbar fusion patients improving from 9.35 ± 0.7 to 4.87 ± 2.3 (P = 0.008). They concluded that SPECT-CT/CT may offer a diagnostic advantage over current imaging modalities in identifying primary PGs.14
There were several examples of a more focal treatment plan being chosen after the addition of SPECT-CT. This was most significantly demonstrable in cases where a patient presented with axial spine pain and a significant deformity in the setting of multilevel arthropathy on traditional imaging. SPECT-CT then demonstrated only 1–2 levels of metabolic activity, thus supporting a smaller surgical operation over potentially a larger thoracolumbar reconstruction.
Despite these promising results, this study has some limitations. First, it is important to interpret these data in the context of a complex patient population. Our knowledge of SPECT-CT, as well as its correlation with painful pathology and its role in the management of complex multilevel degenerative disease, is still evolving. Ultimately, postoperative patient-reported outcome measures will be needed to show that these changes result in more successful surgery and better patient outcomes. Although we are currently focusing on the impact with respect to our clinical decision-making, patient-reported outcome measures data are being collected for future studies to address surgical and treatment effectiveness, as well as any cost implications or savings. In addition, our survey did not clarify subcategories that led to the large reduction in need for further testing before and after SPECT-CT. It is our belief that this is best interpreted as a proxy for surgeon confidence in the treatment plan, as SPECT-CT is thought to have been commonly ordered when there was not enough confidence to move forward with a definitive treatment recommendation.
It should be discussed that we do not advocate the use of SPECT-CT as a first-line imaging modality when working up patients with axial neck or low back pain. We strongly support the use of traditional imaging, including radiography and MRI, as first-line imaging choices. In our cohort, SPECT-CT was only used as a supplement when traditional imaging was unable to adequately define a PG that the surgeon could target. To further push this point, our prospective cohort of 110 SPECT-CT patients was obtained after seeing a total of 4462 spine patient consultations. Therefore, the percentage of patients receiving SPECT-CT scans was only 2.47%. Detailed discussions should be had with patients prior to ordering this test, including risks of radiation exposure.
While several studies previously mentioned have alluded to the fact that SPECT-CT can potentially be used as a diagnostic tool to locate PGs in the spine, this is the first study to our knowledge that directly assesses the impact of SPECT-CT on diagnosis and treatment decision-making by spine surgeons. Our data demonstrate that SPECT-CT has significant potential to affect management decisions among spine surgeons when used as a supplement to standard imaging.
Conclusions
SPECT-CT appears to be a valuable diagnostic tool in the assessment of symptomatic axial neck and back pain. Its ability to detect active pathological processes may aid in pinpointing PGs and guiding treatment strategies. Our initial results show an increased ability to identify specific treatment targets while limiting the need for additional workup, possibly resulting in increased diagnostic accuracy and more effective treatment recommendations when compared with traditional imaging alone. SPECT-CT had impactful changes to the treatment plan and recommendations. These findings suggest the potential for SPECT-CT imaging to play a significant role in the clinical decision-making process for this patient population. Further research is warranted to validate these preliminary findings and to establish guidelines for the use of SPECT-CT imaging in the management of axial neck and back pain.
Footnotes
Funding This study was supported by a grant from the Scripps Health Medical Group.
Declaration of Conflicting Interests The authors report no conflicts of interest in this work.
Disclosures Gregory Mundis reports grants/contracts from Medtronic, Sofamor Danek, Globus, and Orthofix; royalties/licenses from NuVasive, Seaspine, and Stryker; consulting fees from Carlsmed, NuVasive, Seaspine, SI-Bone, and Viseon; leadership or fiduciary roles for Scoliosis Research Society, Society of Minimally Invasive Spine Surgery, San Diego Orthopaedic Society, Global Spine Outreach, and San Diego Spine Foundation; and stock/stock options for Alphatec Spine, NuVasive, and Orthofix. Hani Malone reports consulting fees from Atec Spine and Orthofix and serves on the Education Committee of Society of Minimally Invasive Spine Surgery. James Bruffey reports royalties/licenses from Globus and Seaspine; consulting fees and payment/honoraria from NuVasive and Seaspine; and stock/stock options from Alphatec, Nuvasive, and Seaspine. Robert Eastlack reports grants/contracts from Medtronic, Sofamor Danek, Globus, and Seaspine; royalties/licenses from Aseculap/B.Braun, Globus, NuVasive, Seaspine, and SI-Bone; consulting fees from Aesculap/B.Braun, Amgen Co, Johnson & Johnson, Kuros, Medtronic, Neo Spine, NuVasive, Silony, Spinal Elements, and Seaspine; payment/honoraria from Radius; leadership or fiduciary roles for San Diego Orthopaedic Research Society, San Diego Spine Foundation, and Scoliosis Research Society; and stock/stock options for Aclarion, Alphatec Spine, Orthofix, NuVasive, and Spine Innovations. The remaining authors have no disclosures.
- This manuscript is generously published free of charge by ISASS, the International Society for the Advancement of Spine Surgery. Copyright © 2025 ISASS. To see more or order reprints or permissions, see http://ijssurgery.com.
References
- 1.↵Boden SD , Davis DO , Dina TS , Patronas NJ , Wiesel SW . Abnormal magnetic-resonance scans of the lumbar spine in asymptomatic subjects. a prospective investigation. J Bone Joint Surg Am. 1990;72(3):403–408. 10.2106/00004623-199072030-00013
- 2.↵Saha S , Burke C , Desai A , Vijayanathan S , Gnanasegaran G . SPECT-CT: applications in musculoskeletal radiology. Br J Radiol. 2013;86(1031):20120519. 10.1259/bjr.20120519
- 3.↵Carragee EJ , Chen Y , Tanner CM , Truong T , Lau E , Brito JL . Provocative discography in patients after limited lumbar discectomy: a controlled, randomized study of pain response in symptomatic and asymptomatic subjects. Spine (Phila Pa 1976). 2000;25(23):3065–3071. 10.1097/00007632-200012010-00014
- 4.↵Israel O , Pellet O , Biassoni L , et al . Two decades of SPECT/CT - the coming of age of a technology: an updated review of literature evidence. Eur J Nucl Med Mol Imaging. 2019;46(10):1990–2012. 10.1007/s00259-019-04404-6
- 5.↵Waldman LE , Scharf SC . Bone SPECT/CT of the spine, foot, and ankle: evaluation of surgical patients. Semin Nucl Med. 2017;47(6):639–646. 10.1053/j.semnuclmed.2017.07.007
- 6.↵Upadhyay B , Mo J , Beadsmoore C , Marshall T , Toms A , Buscombe J . Technetium-99m methylene diphosphonate single-photon emission computed tomography/computed tomography of the foot and ankle. World J Nucl Med. 2017;16(2):88–100. 10.4103/1450-1147.203077
- 7.↵Lu S-J , Ul Hassan F , Vijayanathan S , Gnanasegaran G . Radionuclide bone SPECT/CT in the evaluation of knee pain: comparing two-phase bone scintigraphy, SPECT and SPECT/CT. Br J Radiol. 2018;91(1090):20180168. 10.1259/bjr.20180168
- 8.↵Corre AL , Huynh KP , Dhaliwal RS , Bain GI . Development of a protocol for SPECT/CT in the assessment of wrist disorders. J Wrist Surg. 2016;5(4):297–305. 10.1055/s-0036-1583314
- 9.↵Dobrindt O , Amthauer H , Krueger A , et al . Hybrid SPECT/CT for the assessment of a painful hip after uncemented total hip arthroplasty. BMC Med Imaging. 2015;15(1):18. 10.1186/s12880-015-0056-1
- 10.↵Arıcan P , Okudan B , Şefizade R , Naldöken S . Diagnostic value of bone SPECT/CT in patients with suspected osteomyelitis. Mol Imaging Radionucl Ther. 2019;28(3):89–95. 10.4274/mirt.galenos.2019.20053
- 11.↵Al-Riyami K , Gnanasegaran G , Van den Wyngaert T , Bomanji J . Bone SPECT/CT in the postoperative spine: a focus on spinal fusion. Eur J Nucl Med Mol Imaging. 2017;44(12):2094–2104. 10.1007/s00259-017-3765-6
- 12.↵Kato S , Demura S , Matsubara H , et al . Utility of bone SPECT/CT to identify the primary cause of pain in elderly patients with degenerative lumbar spine disease. J Orthop Surg Res. 2019;14(1):185. 10.1186/s13018-019-1236-4
- 13.↵Lehman VT , Murphy RC , Maus TP . 99mTc-MDP SPECT/CT of the spine and sacrum at a multispecialty institution: clinical use, findings, and impact on patient management. Nucl Med Commun. 2013;34(11):1097–1106. 10.1097/MNM.0b013e328364bfa6
- 14.↵Tender G , Constantinescu A , Conger A , DiGiorgio A . Primary pain generator identification by CT-SPECT in a patient with low back pain: a case report. BMC Res Notes. 2017;10(1):132:132. 10.1186/s13104-017-2458-3
- 15.↵Shur N , Corrigan A , Agrawal K , Desai A , Gnanasegaran G . Radiological and radionuclide imaging of degenerative disease of the facet joints. Indian J Nucl Med. 2015;30(3):191–198. 10.4103/0972-3919.158526
- 16.↵Matar HE , Navalkissoor S , Berovic M , et al . Is hybrid imaging (SPECT/CT) a useful adjunct in the management of suspected facet joints arthropathy? Int Orthop. 2013;37(5):865–870. 10.1007/s00264-013-1811-y
- 17.↵Brusko GD , Perez-Roman RJ , Tapamo H , Burks SS , Serafini AN , Wang MY . Preoperative SPECT imaging as a tool for surgical planning in patients with axial neck and back pain. Neurosurg Focus. 2019;47(6):E19. 10.3171/2019.9.FOCUS19648
- 18.↵Lee I , Budiawan H , Moon JY , et al . The value of SPECT/CT in localizing pain site and prediction of treatment response in patients with chronic low back pain. J Korean Med Sci. 2014;29(12):1711–1716. 10.3346/jkms.2014.29.12.1711
