Wrong-level surgery is a unique pitfall in spinal surgery and is part of the wider field of wrong-site surgery. Wrong-site surgery affects both patients and surgeons and has received much media attention. We performed this systematic review to determine the incidence and prevalence of wrong-level procedures in spinal surgery and to identify effective prevention strategies. We retrieved 12 studies reporting the incidence or prevalence of wrong-site surgery and that provided information about prevention strategies. Of these, ten studies were performed on patients undergoing lumbar spine surgery and two on patients undergoing lumbar, thoracic or cervical spine procedures. A higher frequency of wrong-level surgery in lumbar procedures than in cervical procedures was found. Only one study assessed preventative strategies for wrong-site surgery, demonstrating that current site-verification protocols did not prevent about one-third of the cases. The current literature does not provide a definitive estimate of the occurrence of wrong-site spinal surgery, and there is no published evidence to support the effectiveness of site-verification protocols. Further prevention strategies need to be developed to reduce the risk of wrong-site surgery.

The purpose of this study was to evaluate whether concerns about the release of metal ions in metal-on-metal total hip replacements (THR) should be extended to patients with metal-bearing total disc replacements (TDR). Cobalt and chromium levels in whole blood and serum were measured in ten patients with a single-level TDR after a mean follow-up of 34.5 months (13 to 61) using inductively-coupled plasma mass spectrometry. These metal ion levels were compared with pre-operative control levels in 81 patients and with metal ion levels 12 months after metal-on-metal THR (n = 21) and resurfacing hip replacement (n = 36). Flexion-extension radiographs were used to verify movement of the TDR. Cobalt levels in whole blood and serum were significantly lower in the TDR group than in either the THR (p = 0.007) or the resurfacing group (p < 0.001). Both chromium levels were also significantly lower after TDR versus hip resurfacing (p < 0.001), whereas compared with THR this difference was only significant for serum levels (p = 0.008). All metal ion levels in the THR and resurfacing groups were significantly higher than in the control group (p < 0.001). In the TDR group only cobalt in whole blood appeared to be significantly higher (p < 0.001). The median range of movement of the TDR was 15.5° (10° to 22°). These results suggest that there is minimal cause for concern about high metal ion concentrations after TDR, as the levels appear to be only moderately elevated. However, spinal surgeons using a metal-on-metal TDR should still be aware of concerns expressed in the hip replacement literature about toxicity from elevated metal ion levels, and inform their patients appropriately

Establish the positive predictive value of clinical examination predicted radicular level to MRI. To identify the value of the Leeds Assessment of Neuropathic Symptoms and Signs (LANSS) assessment tool in the assessment of patients presenting with radicular symptoms of lumbar spine source. 8 patients attending the ESP Orthopaedic triage service, presenting with radicular pain in which MRI is clinically indicated. Prospective study on patients attending ESP Orthopaedic triage service. Patients were clinically examined, both parts LANSS score was completed. Following the assessment a radicular level was selected. Following MRI the results were compared. Positive predicted values (PPV) for clinical examination and sensitivity and specificity of a LANSS score>12 was calculated. LANSS score. MRI report. PPV of 75% of therapist predicted level being same level or adjacent level to MRI stated level. 66% specificity and 100% sensitivity of patients in study with LANNS>12 having MRI evaluated radicular nerve root compression. This pilot suggests that clinical examination and the LANSS score is useful in establishing the presence of radicular nerve root compression. This evidence supports the need for further research

Aim. To evaluate the level of health resource utilisation by patients after lumbar total disc replacement (TDR) for mechanical low back pain. Method. At our centre, 35 patients underwent TDR and were followed prospectively from surgery. All surgery was performed by the senior author. Patients were followed routinely in clinic at yearly intervals. In addition, the patients and their GPs were contacted via telephone. Information gathered included ODI and VAS, satisfaction with surgery and return to work. We specifically established whether the patients continued to seek healthcare, for persistent back symptoms, from professionals (both NHS and private) including their GP, pain clinic, physiotherapist, acupuncturist, chiropractor or another spinal surgeon, and had any further interventions. Results. We have complete dataset on 30 out of 35 patients and are the subject of this study. There were 13 men, with a mean age of 37.7 years (range 28-45 years), and 17 women with a mean age of 49.8 years (range 27-62 years). Surgery was single level in 26 and two levels in 6 cases. Patients were satisfied with the outcome of surgery in 21 cases (70%), not satisfied in 7. Two cases had implant failures. 25 patients were working pre-operatively and 26 were working postoperatively. Eighteen patients required no further healthcare input. Five had had pain clinic reviews, six had seen their GPs (1-6 visits) and one another spinal surgeon (after late liner extrusion). Seven had facet injections and two had epidurals. One patient underwent posterior fusion for implant migration. Conclusion. In our series TDR is successful in 70% and 60% of the entire cohort needed no further healthcare input. After successful TDR there is almost no ongoing use of health resources

To review the accuracy of our systematic process in preventing wrong level lumbar microdiscectomy. X-ray is used to identify the correct level for the skin incision to be made, x-ray is again used if the surgeon is in doubt prior performing the flavotomy. Following a lumbar microdiscectomy a Watson Chane is inserted into the empty disc space and an intra-operative x-ray is taken to confirm the level the discectomy has occurred. Observers A and B independently reviewed intra-operative x-ray in patients undergoing lumbar microdiscectomies and correlated the accuracy of the x-ray in determining correct level surgery against the pre-operative MRI scan and the preposed level of surgery. 123 patients, 66 males and 57 females underwent 127 lumbar microdiscectomy procedures between 2007 and 2009. The levels where surgery occurred are;- L2/3 -1 patient, L3/4–8 patients, L4/5–53 patients and L5/S1-65 patients. Kappa coefficient was used to determine inter-observer and Pearson Correlation coefficient was used to determine the X-ray and MRI relationship. Percentage of patients who required a pre-flavotomy x-ray level check are:- L2/3–100%, L3/4-63%, L4/5–45%, and L5/S1–40%. Pearson's correlation in confirming the level lumbar microdiscectomy was performed using final x-ray and the pre-operative MRI scan was 1. Kappa coefficient between observer A and B was 1. This process of using intra-operative x-ray in determining the exact level where lumbar microdiscectomy was performed is 100% accurate. This is our standard process in preventing wrong level surgery for lumbar microdiscectomy

Inflammatory markers such as the C-reactive protein (CRP), white blood cell count and body temperature are easy to measure and are used as indicators of infection. The way in which they change in the early post-operative period after instrumented spinal surgery has not been reported in any depth. We measured these markers pre-operatively and at one, four, seven and 14 days postoperatively in 143 patients who had undergone an instrumented posterior lumbar interbody fusion. The CRP proved to be the only sensitive marker and had returned to its normal level in 48% of patients after 14 days. The CRP on day 7 was never higher than that on day 4. Age, gender, body temperature, operating time and blood loss were not related to the CRP level. A high CRP does not in itself suggest infection, but any increase after four days may presage infection

We treated 31 patients aged 65 years or more with cervical spondylotic myelopathy by microsurgical decompression and fusion at a single most appropriate level, in spite of MRI evidence of compression at several levels. Spinal cord potentials evoked at operation localised the level responsible for the principal lesion at C3-4 in 18 patients, C4-5 in 11 and at C5-6 in two. Despite the frequent coexistence of other age-related conditions, impairing ability to walk, the average Nurick grade improved from 3.5 before operation to 2.2 at a mean follow-up of 48 months. There was also good recovery of finger dexterity and sensitivity. Operation at a single optimal level, as opposed to several, has the advantage of minimising complications, of particular importance in this age group

Aim. A retrospective review of the management of adjacent level discectomy and fusion using a Zero-P (Synthes) cage and report of ease of technique and outcomes. Method. Surgical approach to adjacent level cervical disc protrusion with previous anterior cervical discectomy and fusion (ACDF) can be difficult. We review 4 patients who had previous ACDF with cage and plate who developed new onset adjacent level cervical disc prolepses causing myelopathy. A retrospective review of demographic data, symptoms, details of surgery, pre and post operative radiology, pre and postoperative ODI and pain score, length of stay, complications and follow-up data were collected in all patients. Results. Previous ACDF with plate was performed in all 4 patients an average of 11.6 years ago. Two patients had bilateral approaches previously and both had previous vascular injuries. The average duration of current symptoms was 9 months with a mean age of 65 years. All patients presented with myelopathy and two also had radiculopathy. Multiple level ACDF were operated in 2 patients previously. Revision surgery and dissection on the disc level was restricted by the previous plate. Screws from the previous plate fusion were removed adjacent to the level of surgery and discectomy was performed using distractor pins through the screw sites. Following discectomy a Zero-P cage was used to fusion with DBX under image intensifier guidance. The advantage was not to remove the previous plate and keep the dissection over the scar tissue to the minimal. All patients improved in their radicular symptoms with improvement of their hand function in the myelopaths. There was no complication and post operative radiographs were satisfactory. Conclusions. Use of the Zero-P cage for adjacent level discectomy and fusion was safe without disturbing the previous cage and plate fusion or stability

Introduction/Aim. Intra-operative localisation of thoracic spine levels can be difficult due to anatomical constraints such as scapular shadow, patient's size and poor bone quality. This is particularly true in cases of thoracic discectomies in which the vertebral bodies appear normal. We describe a simple and reliable technique to identify the correct thoracic spine level. Methods. After induction of general anaesthesia, the patient is placed prone and the pedicle of interest is identified using fluoroscopy. A ‘K’ wire is then inserted percutaneously into this pedicle under image guidance (confirmed in the antero-posterior (AP) and lateral views). The ‘K’ wire is then cut flush and the patient is then positioned laterally and the intended procedure is performed. Results. We routinely use this technique in all our thoracic discectomies. Placing the ‘K’ wire into a fixed point like the pedicle, facilitates rapid intra-operative viewing of the level of interest and is removed easily at the conclusion of surgery. Conclusion. Per-operative placement of the ‘K’ wire avoids the patient undergoing two procedures as some of the other invasive techniques have described in the literature for correct level identification. Furthermore, this technique is simple and requires no more ability than placing an implant in the pedicle under fluoroscopy. It has the added advantage of reducing anaesthetic, surgery and fluoroscopy time

The study is been conducted to compare the outcome of pedicle screw fixation in dorsolumbar fractures by long segment fixation and short segment fixation with a screw in fractured vertebra. Study includes the consecutive patients of dorsolumbar fractures treated by either long segment or short segment fixation. Twenty patients were included in each category. Patients with or without neurological deficit were included. Patients with single fractured vertebra only were included. Patients with single level dorsolumbar fracture were subjected to detailed radiological analysis preoperatively by measurement of height loss and kyphosis angle of fractured vertebra. Detailed neurological status was recorded. During the fixation the pedicle screw was inserted in less affected pedicle of fractured vertebra and decompression if needed was done by hemilaminectomy of other side. Bone graft. Postoperative kyphosis correction and restoration of height was calculated in both the groups. At 3 months, 12months and 24 months the maintenance of corrected kyphosis and restored height was recorded. Neurological examination to record the effect of surgical intervention on neurological recovery was recorded at every examination. All the patients had satisfactory outcome. The loss of correction in both the groups was comparable. The treatment allows easier postoperative nursing and early mobilization of the patient. Segmental fixation with screws at the level of the fracture offers improved biomechanical stability. It allows additional fixation points that may aid in fracture reduction and kyphosis correction. It also reduces the duration of surgery, blood loss as well as cost of implant without significant compromise on outcome. Pedicle screw at the level of fracture in short segment fixations provides added stability, better postoperative maintenance of corrected kyphosis at reduced cost of implant

Back ground:. Previous studies have stated that presence of concomitant back pain has a negative effect on the outcome of lumbar decompression/microdiscectomy but none have actually defined what level of back pain should be considered as significant. This is a study of consecutive patients who underwent a primary single level lumbar micro decompression /microdiscectomy performed by thirty nine surgeons at a single tertiary spinal centre between August 2011 and December 2014. The aim was to determine the differential effect of the intensity of back pain and leg pain as a predictor of outcome. Method and Result:. Data was prospectively collected using SpineTango COMI questionnaires pre-operatively and at 3 months postoperatively. 995 patients who had a complete dataset were included in the analysis. Multivariate regression analysis and ROC curves were used to evaluate factors associated with poor outcome. At 3 months follow up 72.16% of patients were satisfied with the outcome of surgery. The VAS for low back pain was a significant predictor of poor outcome. Of patients with a VAS of 6 or more 34% had a poor outcome following surgery while of patients with a VAS of less than 6, 17% had a poor outcome at three months. Conclusion:. Our study has shown that patients with pre-operative concomitant back pain with VAS of 6 or more have a significantly greater chance of a poor outcome following primary lumbar microdecompressive/microdiscectomy surgery as compared to those with a back pain VAS of less than 6

Purpose. A new approach to the reporting of health outcomes involves assessing the proportion of patients achieving a level of symptoms that they feel they could live with. We evaluated the acceptable level of pain in patients after surgery for lumbar disc herniation (LDH). Methods. 12 mo after first-time surgery for LDH, patients completed 0–10 scales for back pain and leg pain and a question: “if you had to spend the rest of your life with the symptoms you have now, how would feel about it?,” answered on a 5-point Likert scale from “very satisfied” to “very dissatisfied”. This was dichotomised and used as the external criterion in receiver operating characteristics (ROC) analysis to derive the cut-off score for pain that best indicated being at least “somewhat satisfied” with the symptom state. Results. 1,209 (91%) patients returned a questionnaire, of which 611 (51%) reported being at least somewhat satisfied with their symptom state. The area under the curve for the ROC analysis was 0.91 (95% CI, 0.89–0.92), indicating a good ability of the pain score to discriminate between being in a satisfactory state or not. The cut-off indicating a satisfactory symptom state was ≤2 points on the pain scale (sens, 76% and spec 89%). Conclusion. Most spine interventions are aimed at decreasing pain but only rarely do they totally eliminate it. Determination of the % patients achieving an acceptable symptom state for pain may represent a useful and more stringent target for denoting surgical success in the treatment of painful spinal disorders

Herniated intervertebral disc tissue has been shown to produce a number of proinflammatory mediators and cytokines, but there have been no similar studies using discs from patients with discogenic low back pain. We have compared the levels of production of interleukin-6 (IL-6), interleukin-8 (IL-8) and prostaglandin E. 2. (PGE. 2. ) in disc tissue from patients undergoing discectomy for sciatica (63) with that from patients undergoing fusion for discogenic low back pain (20) using an enzyme-linked immunoabsorbent assay. There was a statistically significant difference between levels of production of IL-6 and IL-8 in the sciatica and low back pain groups (p < 0.006 and p < 0.003, respectively). The high levels of proinflammatory mediator found in disc tissue from patients undergoing fusion suggest that production of proinflammatory mediators within the nucleus pulposus may be a major factor in the genesis of a painful lumbar disc

There are many causes of paraspinal muscle weakness which give rise to the dropped-head syndrome. In the upper cervical spine the central portion of the spinal cord innervates the cervical paraspinal muscles. Dropped-head syndrome resulting from injury to the central spinal cord at this level has not previously been described. We report two patients who were treated acutely for this condition. Both presented with weakness in the upper limbs and paraspinal cervical musculature after a fracture of C2. Despite improvement in the strength of the upper limbs, the paraspinal muscle weakness persisted in both patients. One ultimately underwent cervicothoracic fusion to treat her dropped-head syndrome. While the cause of the dropped-head syndrome cannot be definitively ascribed to the injuries to the spinal cord, this pattern is consistent with the known patho-anatomical mechanisms of both injury to the central spinal cord and dropped-head syndrome

We studied 27 patients with low back pain and unilateral L5 or S1 spinal nerve root pain. Significant radiological changes were restricted to the symptomatic root level, when compared with controls. Low back and leg pain were graded on a visual analogue scale. Dermatomal quantitative sensory tests revealed significant elevations of warm, cool and touch perception thresholds in the affected dermatome, compared with controls. These elevations correlated with root pain (warm v L5 root pain; r = 0.88, p < 0.0001), but not with back pain. Low back pain correlated with restriction of anteroposterior spinal flexion (p = 0.02), but not with leg pain. A subset of 16 patients underwent decompressive surgery with improvement of pain scores, sensory thresholds and spinal mobility. A further 14 patients with back pain, multilevel nerve root symptoms and radiological changes were also studied. The only correlation found was of low back pain with spinal movement (p < 0.002). We conclude that, in patients with single level disease, dermatomal sensory threshold elevation and restriction of spinal movement are independent correlates of sciatica and low back pain

Introduction. With the use of each pedicle screw for surgical correction of adolescent idiopathic scoliosis (AIS), there is an increase in instrumentation-related costs, operative time, risk of neural injury, and overall health-care expenses. As such, alternate level screw strategy (ALSS) has been reported as a potential alternative to contiguous multilevel screw strategy (CMSS). Moreover, studies have shown the importance in accounting for the flexibility of the curve based on the fulcrum bending radiograph when assessing postoperative curve correction. Therefore, this study addressed a radiographic and cost analysis comparing CMSS with ALSS for the treatment of thoracic AIS with titanium screws and rod application. Methods. 77 patients with AIS underwent surgery (range 6–15 levels). 35 patients received CMSS, which was characterised as bilateral screw fixation at every level. 42 patients underwent ALSS, which entailed bilateral screw fixation at alternate levels. Titanium rods were used in all cases. Preoperative and postoperative posteroanterior and fulcrum bending radiographic Cobb angles were obtained for all patients. The fulcrum flexibility and the fulcrum bending correction index (FBCI) were assessed. Cost analysis was also done. Results. We recorded a statistically significant difference between screw strategy-type to that of preoperative and postoperative Cobb angles, and postoperative curve correction (p<0·05). No statistically significant difference was noted between screw strategy-type and fulcrum flexibility (CMSS mean 66·9%; ALSS mean 62·7%; p>0·05). The mean FBCIs of the CMSS and ALSS were 126·1% and 122·1%, respectively, and did not differ significantly (p=0·734). Compared with CMSS, ALSS was associated with pedicle screw cost reductions of up to 46·2%. Conclusions. This study is the first to show that irrespective of curve rigidity, ALSS with fewer pedicle screws can achieve comparable FBCI as CMSS. We attribute this finding to the relatively flexible titanium rods used in this study. Thus, ALSS is as effective as CMSS in terms of coronal curve correction, and it has the added benefits of reducing operative time and neurological complication risk. Furthermore, it offers the possibility of better kyphosis restoration compared with the lordosing effect of CMSS

The purpose of this study was to evaluate and compare the effect of short segment pedicle screw instrumentation and an intermediate screw (SSPI+IS) on the radiological outcome of type A thoracolumbar fractures, as judged by the load-sharing classification, percentage canal area reduction and remodelling.

We retrospectively evaluated 39 patients who had undergone hyperlordotic SSPI+IS for an AO-Magerl Type-A thoracolumbar fracture. Their mean age was 35.1 (16 to 60) and the mean follow-up was 22.9 months (12 to 36). There were 26 men and 13 women in the study group. In total, 18 patients had a load-sharing classification score of seven and 21 a score of six. All radiographs and CT scans were evaluated for sagittal index, anterior body height compression (%ABC), spinal canal area and encroachment. There were no significant differences between the low and high score groups with respect to age, duration of follow-up, pre-operative sagittal index or pre-operative anterior body height compression (p = 0.217, 0.104, 0.104, and 0.109 respectively). The mean pre-operative sagittal index was 19.6° (12° to 28°) which was corrected to -1.8° (-5° to 3°) post-operatively and 2.4° (0° to 8°) at final follow-up (p = 0.835 for sagittal deformity). No patient needed revision for loss of correction or failure of instrumentation.

Hyperlordotic reduction and short segment pedicle screw instrumentation and an intermediate screw is a safe and effective method of treating burst fractures of the thoracolumbar spine. It gives excellent radiological results with a very low rate of failure regardless of whether the fractures have a high or low load-sharing classification score.

Cite this article: Bone Joint J 2014;96-B:541–7.

Aims. The aims of this study were first, to determine if adding fusion to a decompression of the lumbar spine for spinal stenosis decreases the rate of radiological restenosis and/or proximal adjacent level stenosis two years after surgery, and second, to evaluate the change in vertebral slip two years after surgery with and without fusion. Methods. The Swedish Spinal Stenosis Study (SSSS) was conducted between 2006 and 2012 at five public and two private hospitals. Six centres participated in this two-year MRI follow-up. We randomized 222 patients with central lumbar spinal stenosis at one or two adjacent levels into two groups, decompression alone and decompression with fusion. The presence or absence of a preoperative spondylolisthesis was noted. A new stenosis on two-year MRI was used as the primary outcome, defined as a dural sac cross-sectional area ≤ 75 mm. 2. at the operated level (restenosis) and/or at the level above (proximal adjacent level stenosis). Results. A total of 211 patients underwent surgery at a mean age of 66 years (69% female): 103 were treated by decompression with fusion and 108 by decompression alone. A two-year MRI was available for 176 (90%) of the eligible patients. A new stenosis at the operated and/or adjacent level occurred more frequently after decompression and fusion than after decompression alone (47% vs 29%; p = 0.020). The difference remained in the subgroup with a preoperative spondylolisthesis, (48% vs 24%; p = 0.020), but did not reach significance for those without (45% vs 35%; p = 0.488). Proximal adjacent level stenosis was more common after fusion than after decompression alone (44% vs 17%; p < 0.001). Restenosis at the operated level was less frequent after fusion than decompression alone (4% vs 14%; p = 0.036). Vertebral slip increased by 1.1 mm after decompression alone, regardless of whether a preoperative spondylolisthesis was present or not. Conclusion. Adding fusion to a decompression increased the rate of new stenosis on two-year MRI, even when a spondylolisthesis was present preoperatively. This supports decompression alone as the preferred method of surgery for spinal stenosis, whether or not a degenerative spondylolisthesis is present preoperatively. Cite this article: Bone Joint J 2022;104-B(12):1343–1351

Aims. Historically, patients undergoing surgery for adolescent idiopathic scoliosis (AIS) have been nursed postoperatively in a critical care (CC) setting because of the challenges posed by prone positioning, extensive exposures, prolonged operating times, significant blood loss, major intraoperative fluid shifts, cardiopulmonary complications, and difficulty in postoperative pain management. The primary aim of this paper was to determine whether a scoring system, which uses Cobb angle, forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and number of levels to be fused, is a valid method of predicting the need for postoperative critical care in AIS patients who are to undergo scoliosis correction with posterior spinal fusion (PSF). Methods. We retrospectively reviewed all AIS patients who had undergone PSF between January 2018 and January 2020 in a specialist tertiary spinal referral centre. All patients were assessed preoperatively in an anaesthetic clinic. Postoperative care was defined as ward-based (WB) or critical care (CC), based on the preoperative FEV1, FVC, major curve Cobb angle, and the planned number of instrumented levels. Results. Overall, 105 patients were enrolled. Their mean age was 15.5 years (11 to 25) with a mean weight of 55 kg (35 to 103). The mean Cobb angle was 68° (38° to 122°). Of these, 38 patients were preoperatively scored to receive postoperative CC. However, only 19% of the cohort (20/105) actually needed CC-level support. Based on these figures, and an average paediatric intensive care unit stay of one day before stepdown to ward-based care, the potential cost-saving on the first postoperative night for this cohort was over £20,000. There was no statistically significant difference between the Total Pathway Score (TPS), the numerical representation of the four factors being assessed, and the actual level of care received (p = 0.052) or the American Society of Anesthesiologists grade (p = 0.187). Binary logistic regression analysis of the TPS variables showed that the preoperative Cobb angle was the only variable which significantly predicted the need for critical care. Conclusion. Most patients undergoing posterior fusion surgery for AIS do not need critical care. Of the readily available preoperative measures, the Cobb angle is the only predictor of the need for higher levels of care, and has a threshold value of 74.5°. Cite this article: Bone Joint J 2024;106-B(7):713–719

Aims. To investigate the correlations among cytokines and regulatory T cells (T-regs) in ankylosing spondylitis (AS) patients, and their changes after anti-tumour necrosis factor-α (TNF-α) treatment. Methods. We included 72 AS patients with detailed medical records, disease activity score (Bath Ankylosing Spondylitis Disease Activity Index), functional index (Bath Ankylosing Spondylitis Functional Index), and laboratory data (interleukin (IL)-2, IL-4, IL-10, TNF-α, interferon (IFN)-γ, transforming growth factor (TGF)-β, ESR, and CRP). Their peripheral blood mononuclear cells (PBMCs) were marked with anti-CD4, anti-CD25, and anti-FoxP3 antibodies, and triple positive T cells were gated by flow cytometry as T-regs. Their correlations were calculated and the changes after anti-TNF-α therapy were compared. Results. The frequency of T-regs in PBMCs was positively correlated to ESR and CRP in AS (r = 0.35 and 0.43; p = 0.032 and 0.027, respectively), and there was also a significant correlation between serum level of TNF-α and CRP (p = 0.041). The frequency of T-regs in PBMCs positively correlated to serum levels of TNF-α, IL-10, and TGF-β, while IL-2, IL-4, and IFN-γ showed opposite results. After anti-TNF-α treatment, there were significantly lower serum levels of TNF-α, IL-10, TGF-β, and frequency of T-regs in PBMCs among these AS patients (p = 0.026, 0.032, 0.029, and 0.037, respectively). Conclusion. In AS patients, proinflammatory cytokine may give positive feedback to induce more T-reg production and anti-inflammatory cytokine secretion to suppress this inflammatory status, and they can be reversed by anti-TNF-α therapy. However, the detailed interactions among T-regs and complex cytokine networks in autoinflammatory diseases still need more studies and further functional assay. Cite this article: Bone Joint Res 2023;12(2):133–137