Imaging for Dupuytren disease: a systematic review of the literature

Diagnosis

Five studies described the use of US and/or MRI for the diagnosis of patients with DD, that had an atypical presentation [18–22]. In two cases, US and MRI did not lead to a diagnosis prior to surgery and DD was diagnosed upon histology [19, 21]. In the other three case-report US and/or MRI led to a wrong diagnosis prior to surgery and histology showed that the final diagnosis was DD [18, 20, 22].

In the two other studies, US was used to diagnose DD in patients with a more typical presentation, in which US was helpful in confirming the diagnosis that was based on clinical examination [23, 24].

In summary, imaging was not instrumental in diagnosing DD in any of the patients with an atypical presentation, but did assist in the diagnosis of DD in patients with a more typical presentation.

Measurement of disease extent

These studies show that MRI can accurately assess disease extent. However, for US it is unknown, as there were no available studies on the use of US to measure disease extent.

Measurement of disease activity

The third study described the use of MRI to measure disease stage by correlating MRI signal intensity to histological results [26]. In total, 22 cords and 13 nodules were found. In all cords and nodules, a low to intermediate signal intensity corresponded to low cellularity and an intermediate to high signal intensity corresponded to high cellularity or mixed composition.

These studies suggest that echogenicity/elasticity and MRI signal intensity are a reflection of disease activity, of which the last two studies have substantiated this hypothesis with study results.

Guidance of minimally invasive procedures

Four other studies performed ultrasound guided procedures [32–35]. The first showed the results of a patient undergoing US-guided PNF followed by osteopathic manipulative treatment [32]. The patient did not experience post-operative complications. The second study prospectively followed the results of US-guided CCH injections in a cohort of 33 DD patients [35]. No flexor tendon ruptures or damages to the NV-bundle were reported. In the last two studies, by the same authors, complications of a variety of US guided procedures in the hand were evaluated. These studies have suspected data-overlap, however, since the research question differed and no meta-analysis is conducted with the data, we decided to include both studies. In the first study, 513 procedures in 402 patients were conducted, of which 105 were Dupuytren contractures [34]. No instance of tendon-rupture or damage to the NV-bundle was reported in the whole group. In the other study, 63 US-guided procedures were conducted in 43 patients on anti-coagulants, of which 12 were Dupuytren contractures [33]. The anti-coagulants were not interrupted and local anaesthesia with epinephrine was used. No instance of clinically relevant hematoma was reported.

The conclusion of these articles is that US guided minimally invasive surgery is safe and result are satisfactory. However, none of these studies used a control group, which is why the additional value of US cannot be determined.

Evaluation of treatment

Two studies used US or MRI for the follow-up of minimally invasive procedures. In the first study, gap width of ruptured cords was evaluated with US, following CCH or PNF [39]. In all patients undergoing PNF and in 80% of patients undergoing CCH a single gap was detectable at the injection site and there was no significant difference in gap width between the groups. Furthermore, post-operative outcome, with a follow-up of 1 year, was comparable in the two groups. In the second study, MRI was used to evaluate if CCH disrupts or digests the Dupuytren cord [40]. Five patients were examined and MRI showed that signal intensity of the injected cords increased significantly, most likely because of tissue reaction to the injected CCH. Furthermore, the volume of a Dupuytren cord decreased significantly at 30 days post-injection. In summary, US and MRI were both used for the follow-up of different treatment modalities and a variety of outcome parameters was measured following treatment, like volume, signal intensity and gap-width of a cord.

Diagnosis

As pointed out in the introduction, DD is usually diagnosed by physical examination [10]. However, in all case-reports that described the use of US and/or MRI for the diagnosis of DD because of an atypical presentation, histology was required to make a final diagnosis, which is the gold standard [18–22]. This implies that US and MRI cannot differentiate DD from other soft tissue diseases to set the diagnosis. However, this can also be a reflection of the lacking knowledge of typical imaging features that characterise DD on US and MRI.

Furthermore, two studies concluded that US may be helpful in supporting the diagnosis for patients with a more typical presentation of DD [23, 24]. However, it is questionable if US is of additional value when clinical signs of the disease are evident.

In our opinion, imaging should still be performed for certain patients, to acquire additional information such as extent, dimensions and affection of neighbouring structures of an undefined lesion, but there is no place for routine imaging in the diagnosis of DD.

Measurement of disease extent

Two studies point out that MRI can accurately measure disease extent of DD [25, 26], which may be valuable in clinical management. However, at present, the choice of surgery is not primarily based on the extent of the disease, but more on the severity of contracture and patient complaints, which can also be monitored using physical examination [10, 45]. This is why the use of MRI for measurement of disease extent seems to be a cost-ineffective method to add to regular monitoring of patients with DD.

Measurement of disease stage

Several studies hypothesise that there is a relation between echogenicity and signal intensity of Dupuytren tissue and disease stage [26–28]. If US and MRI are indeed able to reflect cellularity of nodules and cords and hereby disease stage, this would be of importance in the monitoring of patients with early disease.

However, the overall evidence is poor. One study reports on the use of US-elastography and hypothesizes that it may differentiate both the acute and chronic findings in DD [27]. Unfortunately, this study comprised of only one patient and results were not substantiated with histology or follow-up. Another study concluded that echogenicity of Dupuytren cords may be a related to recurrence [28]. However, the inter-rater reliability of assessing nodularity of cords was poor (Cohen’s kappa = 0.38). Also, the authors did not conduct any statistical analyses to show a significant difference in the occurrence of recurrence between fibrillar and nodular cords. Finally, no clear definition of recurrence was used in this article. Recurrence was defined as either residual disease (a palpable cord without recurrent contracture) or recurrent contracture. In our opinion this definition is nonspecific, as DD tissue is not excised during CCH-injections and PNF, which is why it is expected that most patients have signs of residual disease. Recurrent contracture is more clinically relevant, but for this outcome parameter no cut-off value was described. The relation between echogenicity and activity of a DD nodule has also been reported in a descriptive article by Créteur et al. [11]. This article was not included in the analyses since the conclusions were based on an expert opinion of the author and no patient data were provided.

The final study in this category showed that MRI signal intensity corresponds to disease stage, which was determined using the gold standard histology [26]. These results seem promising, however, as US is easier to access, less expensive and patient-friendlier than MRI, it would be very interesting to investigate if echogenicity also corresponds to cellularity in the future. If this is the case, US can be used regularly to assess if patients are at risk of an aggressive course of DD, which is helpful in disease monitoring and in the future also for the selection of patients that are eligible for treatment aiming at disease control [41, 46].

Guidance of minimally invasive procedures

The main reason to perform US-guided minimally invasive procedures is to enhance safety. In addition to that US-guidance may optimize results. The available literature showed that displaced NV-bundles could be detected using (Doppler)-US [29, 30] and that US-guided minimally invasive surgery had a low complication rate (no incidence of flexor tendon rupture or damage to NV-bundle) [31–35]. Furthermore, ultrasound guided procedures had satisfactory results [31, 32, 35]. However, no study used a control group of patients undergoing non-US-guided minimally invasive surgery. When comparing the results to studies that did not perform US, there does not seem to be much difference in both complication rate and reduction of contracture [47–54]. A randomized controlled trial should be conducted to analyse whether US is really of additional value in pre- and peri-operative management.

Evaluation of treatment

The last application that was described for US and MRI, was evaluation of several treatment modalities. The number of studies reporting the outcomes of non-surgical treatment aiming at disease control of patients with early DD is increasing [41, 55]. As these patients do not have contractures yet, there is need for an alternative reliable outcome parameter. This is why several studies report the use of imaging to follow-up treatment outcome of non-surgical procedures for patients with early DD [36–38]. In our opinion, the use of US and MRI to follow-up size and signal of early DD nodules is most relevant as, currently, the only other reliable measurement instruments for patients without contractures is physical examination, which only measures area of disease in one plane and measures the projection of DD on the overlying skin [10]. However, no information on the reliability of these imaging modalities for the measurement of area of early DD is available yet. Studies covering the reliability of multiple measurements by a single observer (intra-observer reliability) and measurements by multiple observers (inter-observer reliability) have to be conducted first, to determine the accuracy of US and MRI in the measurement of disease extent in patients with early DD.

Furthermore, imaging for the follow-up of minimally invasive surgery in patients with contractures was described [39, 40]. The results of follow-up of CCH-injections were contradicting. While one study observed an overall decrease of the DD cords [40], the other study observed a local disruption at the injection site comparable to that of PNF [39]. This may be caused by the difference in follow-up time and also by the different imaging modality used (MRI vs US). A study measuring cord volume multiple times following PNF and CCH-treatment could give more insight. However, the relevance of such a study is questionable as there was no difference in surgical outcome and recurrence between PNF and CCH [39], which is supported by previous literature on the outcomes of CCH-injection vs PNF [56].

Limitations

Generating a clear overview about imaging for DD was challenging, as there was a wide variety of described applications and overall the included studies had a low level of evidence. Ten studies were case-reports, including only 1 patient [18–23, 25, 27, 32, 36]. In three other studies, less than 10 DD patients were included [24, 38, 40] and in one study the number of observed patients was not described [29]. Of the 9 other studies that did describe a larger cohort of DD patients [26, 28, 31, 35, 37, 39], two studies were conference proceedings [33, 34] and only 1 study included a control group with healthy volunteers for a part of the study [30]. All studies were observational, and most lacked adequate statistical methods. The median level of evidence was 4, and no randomized controlled trials were found.

The inclusion of case-reports and conference proceedings may also be seen as weakness of this study. However, as this is the first systematic review on imaging for DD specifically, it was of interest to include as many studies as possible that showed original data, so that the provided information was as complete as possible. Although the search string that was used was selected to be inclusive, it is possible that some studies were not found by our review. Some studies may have used imaging, but not mentioned this in the title, abstract or keywords. However, because of this it is unlikely that these studies aimed to emphasize the value of imaging for DD. Also, we decided to exclude review articles. Although some of these articles did show original US/MRI-images of patients with DD [11–13, 57–67], no original data on one of the possible applications of imaging for DD were given in these articles or the information provided was based on an expert opinion.

Another limitation is that there is a risk of publication bias. Studies that found a valuable application of imaging for DD are more likely to be published than studies that did not show any relevant findings. Finally, relevant articles may have been missed because they were excluded based on language.