Diagnosis of post-traumatic complex regional pain syndrome of the hand: current role of sympathetic skin response and three-phase bone scintigraphy

[Sensitivity of the sympathetic skin response and scintigraphy in the diagnosis of complex regional pain syndrome]

OBJECTIVE

To evaluate the sensitivity of sympathetic skin response (SSR) and compare it with scintigraphy in patients with complex regional pain syndrome diagnosed according to the Budapest criteria.

MATERIAL AND METHODS

Twenty-two patients with complex regional pain syndrome who attended the Rehabilitation and Physical Medicine Department between January-2018 and May-2022 have been prospectively evaluated. The scintigraphy was considered positive if in the 1st-2nd phase slight asymmetric and diffuse uptake was observed, or when in the 3rd phase marked periarticular radioisotope uptake was observed. SSR was abnormal if: a) no response after 20 stimuli; b) lack of habituation with permanence of the stimuli greater than 67.2%.

RESULTS

Age 55.4±8.57 years. Complex regional pain syndrome was more frequent in women (90.9%), more common in upper limbs (68.2%) than lower limbs (31.8%). In SSR, we have observed normal response (<67.2%) in 2 patients (11.1%), lack of SSR in 2 patients (11.1%) and lack of habituation (>67.2%) in 14 patients (77.8%). In total, 16 patients presented abnormal or absent responses (88.8%). The diagnostic sensitivity of scintigraphy is similar to that of SSR (89.5% vs 88.8%), with no statistical difference (P=.6721).

CONCLUSION

Scintigraphy has shown similar sensitivity to SSR, although the simplicity, security, low cost, non-ionizing and non-invasiveness of the latter technique suggest that it could be more cost-effective. The lack of habituation and the absence of response could identify response patterns and localize the involvement in the afferent, central, efferent or post-ganglionic pathways.

Relationships of autonomic dysfunction with disease severity and neuropathic pain features in fibromyalgia: is it really a sympathetically maintained neuropathic pain?

Background

The pathophysiology of fibromyalgia (FM) involves many mechanisms including central nervous system sensitization theory, autonomic nervous system (ANS) dysfunction, and recently small fiber neuropathy. While the small fiber neuropathy itself can cause ANS dysfunction and neuropathic pain (NP), it is still unknown whether ANS problems have an association with severity of disease and NP in patients with FM. The aim of this study was to evaluate ANS dysfunction in FM patients and to explore possible associations of ANS dysfunction with disease severity and NP.

Methods

Twenty-nine FM patients and 20 healthy controls were included in this cross-sectional study. Participants were tested using sympathetic skin responses (SSR) and R-R interval variation analyses for sympathetic and parasympathetic ANS dysfunction, respectively. Disease severity and somatic symptoms of patients with FM were evaluated using the ACR-2010 scales and Fibromyalgia Impact Questionnaire, and NP symptoms were evaluated using the Pain Detect Questionnaire and Douleur Neuropathique questionnaire.

Results

FM patients were found to have ANS dysfunction characterized by increased sympathetic response and decreased parasympathetic response. SSR amplitudes were found to be correlated with a more severe disease. Although non-significant, NP severity tended to be associated with a decrease in sympathetic and parasympathetic activities.

Conclusions

ANS dysfunction may play a role in the pathophysiology of FM. The trend of decreased ANS functions in FM patients exhibiting NP contradicts the notion that FM is a sympathetically maintained NP and may be explained with small fiber involvement.

Evaluation of the Sympathetic Skin Response in Men with Chronic Prostatitis: A Case-Control Study

BACKGROUND

Etiological factors involved in chronic prostatitis (CP) type IIIb and chronic pelvic pain are not sufficiently understood; however, the nervous system has a significant role in the generation and maintenance of chronic pelvic pain. This study was designed to evaluate the sympathetic skin response (SSR) in men with CP type IIIb compared to normal population.

PATIENTS AND METHODS

For two years, about 14 patients suffering from CP type IIIb according to NIH-CPSI and 26 healthy control men were enrolled in this study. SSR was performed in all the subjects with a standard method. Bilateral palmar and plantar latency and amplitude of SSR were recorded in response to the median and tibial nerve electrical stimulations. SSR is considered abnormal when the latency is prolonged, and the amplitude reduced.

RESULTS

SSR latency in the left and right median nerve was significantly prolonged in the patient with CP type IIIb group compared to the control group (p=0.039 and 0.006, respectively). Additionally, the amplitude was reduced in patients with CP type IIIb group compared to the control group in the right tibial nerve (p=0.017).

CONCLUSION

Sympathetic skin response may be a helpful diagnostic test for men with chronic prostatitis type IIIb. However, this observation needs to be validated in a large sample cohort study with long-term follow-up.

Utility of Radionuclide Bone Scintigraphy in Complex Regional Pain Syndrome

PURPOSE OF REVIEW

To describe the current understanding of the role of three-phase bone scintigraphy (TPBS) in the diagnosis and management of complex regional pain syndrome (CRPS), discuss its advantages and limitations, and present three examples of TPBS patterns typically seen in CRPS patients.

RECENT FINDINGS

CRPS is a debilitating disorder frequently presenting with pain to ordinarily non-painful stimuli, redness, swelling, following fractures, stroke, myocardial infarction, surgery, or even minor trauma, and its diagnosis, based on clinical criteria and supportive imaging findings, is difficult. Of the available adjunctive diagnostic imaging modalities, radionuclide bone scintigraphy using a TPBS protocol is the most sensitive and specific for detecting abnormalities commonly seen with this condition-classically, increased periarticular uptake on delayed phase of TPBS, with variable increased uptake on perfusion phases, depending on chronicity. Recent studies have (1) demonstrated a more heterogeneous correlation of TPBS findings with CRPS diagnosis using the current Budapest criteria than in studies using older criteria, (2) pointed to the utility of novel quantitative scintigraphic techniques, and (3) highlighted the value of the early perfusion phases of TPBS in predicting treatment response. TPBS remains a valuable imaging adjunct to clinical diagnosis of CRPS. In combination with a multi-modal analgesic approach, TPBS can be used to follow disease course and potentially treatment response, although prospective trials are needed to further delineate its role.

Predictive value of sympathetic skin response in diagnosing complex regional pain syndrome: a case-control study

Objective

To investigate the predictive value of the sympathetic skin response (SSR) in diagnosing complex regional pain syndrome (CRPS) by comparing three diagnostic modalities-SSR, three-phasic bone scans (TPBS), and thermography.

Methods

Thirteen patients with severe limb pain were recruited. Among them, 6 were diagnosed with CRPS according to the proposed revised CRPS clinical diagnostic criteria described by the International Association for the Study of Pain. SSR was measured in either the hands or feet bilaterally and was considered abnormal when the latency was prolonged. A positive TPBS finding was defined as diffuse increased tracer uptake on the delayed image. Thermographic findings were considered positive if a temperature asymmetry greater than 1.00℃ was detected between the extremities.

Results

Five of 6 CRPS patients showed prolonged latency on SSR (83% sensitivity). TPBS was positive in the 5 CRPS patients who underwent TPBS (100% sensitivity). Thermography was positive in 4 of 5 CRPS patients who underwent the procedure (80% sensitivity). The remaining 7 non-CRPS patients differed on examination. SSR latencies within normal limit were noted in 4 of 7 non-CRPS patients (57% specificity). Results were negative in 4 of 5 non-CRPS patients who underwent TPBS (80% specificity), and negative in 3 of 5 non-CRPS patients who underwent thermography (60% specificity).

Conclusion

SSR may be helpful in detecting CRPS.

Usefulness of asymmetry score on quantitative three-phase bone scintigraphy in the evaluation of complex regional pain syndrome

Introduction:

Complex regional pain syndrome (CRPS) is primarily a clinical diagnosis. Diagnostic imaging in CRPS can be used, especially to exclude other disorders. The sensitivity and specificity of three phase bone scintigraphy (TPBS) for the diagnosis of CRPS is variable throughout the literature.

Aim:

To establish a simple and effective quantitative approach to help in the diagnosis of CRPS by TPBS.

Materials and Methods:

TPBS done in patients (n = 68) with suspected CRPS was analyzed retrospectively. They were classified into bone scan positive group (BSP), bone scan negative group (BSN) and non-CRPS group based on diffusely increased periarticular uptake, symmetrical uptake, and focal uptake respectively. Asymmetry score (AS) was also measured between the affected and unaffected side.

Results:

16 patients showed focal uptake, 37 were in BSP group with mean AS score of 1.57 ± 0.5 and 15 were in BSN group with mean AS score of 1.01 ± 0.05. The mean AS was significantly different (P < 0.0001). AS of 1.06 had sensitivity and specificity of 96.43% and 100% respectively (P = 0.0001). There was a trend of negative correlation between the AS and the duration, r = −0.21; however, it was not statistically significant (P = 0.28).

Conclusion:

TPBS should be considered in the evaluation of CRPS to rule out patients who have focal involvement, not diagnostic of CRPS (~24% in this study). Quantitative AS of 1.06 can be included to support visual interpretation in the delayed phase.

Clinical applications of SPECT/CT in imaging the extremities

Today, SPECT/CT is increasingly used and available in the majority of larger nuclear medicine departments. Several applications of SPECT/CT as a supplement to or replacement for traditional conventional bone scintigraphy have been established in recent years. SPECT/CT of the upper and lower extremities is valuable in many conditions with abnormal bone turnover due to trauma, inflammation, infection, degeneration or tumour. SPECT/CT is often used in patients if conventional radiographs are insufficient, if MR image quality is impaired due to metal implants or in patients with contraindications to MR. In complex joints such as those in the foot and wrist, SPECT/CT provides exact anatomical correlation of pathological uptake. In many cases SPECT increases the sensitivity and CT the specificity of the study, increasing confidence in the final diagnosis compared to planar images alone. The CT protocol should be adapted to the clinical question and may vary from very low-dose (e.g. attenuation correction only), to low-dose for anatomical correlation, to normal-dose protocols enabling precise anatomical resolution. The aim of this review is to give an overview of SPECT/CT imaging of the extremities with a focus on the hand and wrist, knee and foot, and for evaluation of patients after joint arthroplasty.

Diagnosis of partial complex regional pain syndrome type 1 of the hand: retrospective study of 16 cases and literature review

Background

The partial form of the complex regional pain syndrome of the hand type 1 (CRPS 1), involving only 1 to 3 fingers, is a rare condition first described in 1972. The aim of the study is to define more precisely the diagnosis workup and the prognosis of this clinical entity.

Methods

Retrospective study of CRPS1 partial form observed during five years in a rehabilitation ward. Application of The Budapest criteria, evaluation of radiological exams, therapeutic results and vocational outcomes. Comparison with cases from literature review.

Results

132 patients were hospitalized with the diagnosis of CRPS type 1 of the hand. 16 partial forms were isolated: 11 men, 5 women with a mean age of 43 years. Among these patients, 14 (88%) met The Budapest criteria and the two remaining cases were diagnosed by using the three phase bone scintigraphy. Only moderate improvement was obtained in the majority of the patients. At the maximal time of follow-up (4 to 9 years), 50% of the patients hadn’t returned to work. From the literature review, 19 cases were eligible for clinical comparisons. The main differences between our series and the literature were: more men involved, later diagnosis and worst prognosis in term of return to work.

Conclusions

This is the largest series of consecutive partial form of CRPS. The Budapest criteria are sufficient for the diagnosis in 88% of cases. As in complete form of CRPS1 of the hand, three phase bone scintigraphy should only be used in doubtful cases in the first six months of the illness. Partial form of CRPS1 of the hand is rare and its prevalence remains unknown. Long term prognosis (4 to 9 years) is poor in our series, 50% of patients didn’t returned to work.

Proposing a scoring system for the research criteria of complex regional pain syndrome

This study evaluated the structure of complex regional pain syndrome (CRPS) population and suggested a weighted scoring system to balance on objective signs. One hundred sixty-eight consecutive patients were evaluated using the Budapest Research Criteria (BRC). By using multidimensional scaling and logistic regression analysis, we analyzed the degree of importance and relationships between objective findings. In addition, a receiver operating characteristic curve was constructed using a weighted score derived from the risk ratio as a diagnostic test. There were correlations between skin color change and edema, and between decreased range of motion and motor dysfunction when multidimensional scaling was applied. The trophic change was excluded by a logistic regression (95% CI; 0.80-11.850). The cutoff point based on weighted score derived from the risk ratios for determining CRPS was 7.88. At this point, the sensitivity, specificity, positive predictive value and negative predictive value were 75.0%, 95.3%, 96.3%, and 70.1%, respectively. We propose a weighted scoring system for the BRC using risk ratios of objective signs. Although a thorough systematic review would be required in the future, this study can contribute to reduction of the possible distortion of the feature of CRPS populations by the BRC.

CRPS I following artificial disc surgery: case report and review of the literature

We report a case of type 1 complex regional pain syndrome (CRPS I) of the left leg following the implantation of an artificial disc type in the L4/5 segment of the lumbar spine using a midline left-sided retroperitoneal approach. This approach included the mobilisation of the sympathetic trunk with incision and resection of the intervertebral disc. The perioperative and immediate postoperative periods were uneventful, but on the second postoperative day the patient complained of a progressive allodynia of the whole left leg in combination with weakness of the limb. Neurological examination did not reveal any radicular deficit or paresis. A sympathetic reaction following the mobilisation of the sympathetic trunk during the ventral preparation of the spine was suspected and investigated further. A diagnosis of CRPS I was proposed, and the patient was treated with analgesia, co-analgesics for pain alienation, and systemic corticosteroid therapy. A computed tomography-guided sympathetic block and lymphatic drainage were performed. Following conservative orthopaedic rehabilitation therapy, the degree of pain, allodynia, weakness, and swelling were reduced and the condition of the patient was ameliorated. The cost-benefit ratio of spinal arthroplasty is still controversial. The utility of this paper is to debate a possible cause of a painful complication, which can invalidate the results of a successful operation.

[Bone scintigraphy in evaluation of bone vascularisation at wrist and hand]

Diphosphonate bone scintigraphy is used since the 1970s for studying bone pathology; it is increasingly common because of increased physical activity of the population. The disphosphonate uptake in bone requires the preservation of bone vascularity and reflects osteoblastic activity; it allows studying the viability of bone. Using data from the literature and our experience, we tried to take stock of its main uses in routine emphasizing the study of vascular and describe its use in fractures of the scaphoid and in the study of vascularised bone transfers. If the value of scintigraphy is well known, the use made by means of pinhole collimator and the market entry of new and more sensitive detectors with better resolution could allow the side of the imaging anatomy of improving the study of the vascularisation of small bone transfers which are increasingly used, particularly at wrist and hand.

Extension fractures of the distal radius in patients older than 50: a prospective randomized study comparing fixation using mixed pins or a palmar fixed-angle plate

We randomized 103 patients over the age of 50 with an unstable closed intra- or extra-articular dorsally displaced distal radius fracture to have either palmar fixed-angle plating (n=50) or 'mixed pinning' (n=53) and compared the clinical and radiological outcomes at 3, 6, 12 and 26 weeks after surgery in a prospective study. Postoperative palmar tilt was significantly better in those stabilized with K-wires, but loss of reduction was statistically less in those stabilized with a plate. At 26 weeks, functional results, assessed by DASH and Herzberg scores, were better in those fixed with a plate.

Imaging in Early Posttraumatic Complex Regional Pain Syndrome

OBJECTIVES

The complex regional pain syndrome type I (CRPS I) still is difficult to diagnose in posttraumatic patients. As CRPS I is a clinical diagnosis the characteristic symptoms have to be differentiated from normal posttraumatic states. Several diagnostic procedures are applied to facilitate an early diagnosis, although their value for diagnosing posttraumatic CRPS I is unclear.

METHODS

One hundred fifty-eight consecutive patients with distal radial fracture were followed up for 16 weeks after trauma. To assess the diagnostic value of the commonly applied methods a detailed clinical examination was carried out 2, 8, and 16 weeks after trauma in conjunction with bilateral thermography, plain radiographs of the hand skeleton, three phase bone scans (TPBSs), and contrast-enhanced magnetic resonance imaging (MRI). All imaging procedures were assessed blinded.

RESULTS

At the end of the observation period 18 patients (11%) were clinically identified as having CRPS I and 13 patients (8%) revealed an incomplete clinical picture which were defined as CRPS borderline cases. The sensitivity of all diagnostic procedures used was poor and decreased between the first and the last examinations (thermography: 45% to 29%; TPBS: 19% to 14%; MRI: 43% to 13%; bilateral radiographs: 36%). In contrast a high specificity was observed in the TPBS and MRI at the eighth and sixteenth-week examinations (TPBS: 96%, 100%; MRI: 78%, 98%) and for bilateral radiographs 8 weeks after trauma (94%). The thermography presented a fair specificity that improved from the second to the sixteenth week (50% to 89%).

DISCUSSION

The poor sensitivity of all tested procedures combined with a reasonable specificity produced a low positive predictive value (17% to 60%) and a moderate negative predictive value (79% to 86%). These results suggest, that those procedures cannot be used as screening tests. Imaging methods are not able to reliably differentiate between normal posttraumatic changes and changes due to CRPS I. Clinical findings remain the gold standard for the diagnosis of CRPS I and the procedures described above may serve as additional tools to establish the diagnosis in doubtful cases.