Complex regional pain syndrome type I of the knee: A systematic literature review

Abstract

In our Center for Pain Medicine, a group of patients reported to have symptoms possibly attributable to complex regional pain syndrome (CRPS) of only the knee(s). Therefore, this study aimed to investigate whether the literature reports on patients with CRPS type I in the knee(s) alone and, if so, to summarize the reported diagnostics, aetiology and treatment strategies of CRPS of the knee(s). Medline, Embase, Cochrane Library, PubMed and Web of Science were searched for articles focusing on a painful disorder of the knee, most likely CRPS type I. Screening on title and abstract was followed by full-text reading and searching of reference lists to determine the final set of relevant articles. Of the 513 articles identified, 31 met the inclusion criteria. These articles reported on a total of 368 patients diagnosed with CRPS of the knee(s) based on the diagnostic criteria used at the time of publication. Knee surgery, especially arthroscopic surgery, was the most common inciting event in developing CRPS of the knee(s). Various treatment strategies were applied with variable outcomes. In conclusion, the scientific literature does report cases of CRPS type I of only the knee(s). This applies when using the diagnostic criteria prevailing at the time of publication and, obviously for a smaller number of cases, also when using the current Budapest criteria set. Arthroscopic knee surgery is described multiple times as the inciting event. We recommend to include CRPS of the knee in future research on the aetiological mechanisms of and optimal treatment for CRPS.

Response to the Letter to the Editor

“…Within the group of 12 patients who all finished the trial period, the following causes of the knee CRPS were given: 7 patients had undergone (arthroscopic) surgery or an arthroscopy, 4 patients had a trauma of the knee (2 had a luxation of the patella and 2 patients had fallen on the specific knee), and 1 patient had a fracture of the tibia plateau. The surgical causes of CRPS confined to the knee are in line with one of our earlier reports concerning CRPS confined to the knee …”

“…We totally agree with the statement of the authors of the letter to the editor that “the incidence of CRPS knee following trauma or otherwise is not well appreciated.” We would like to refer to our earlier published paper in which we concluded that the scientific literature does report cases of complex regional pain syndrome (CRPS) type I of only the knee(s). Our recommendation was to consider CRPS confined to the knee as a medical entity and therefore to include CRPS of only the knee(s) in future research on the etiological mechanisms of and optimal treatment for CRPS …”

Successful Treatment of Intractable Complex Regional Pain Syndrome Type I of the Knee With Dorsal Root Ganglion Stimulation: A Case Report

“…Recently, a systematic review was performed to find evidence for the diagnosis of CRPS of the knee. The authors concluded that this diagnosis has been described before and the best therapy is yet to be found .…”

Layered Approach to the Anterior Knee: Normal Anatomy and Disorders Associated with Anterior Knee Pain

“…Signal intensity alterations related to disuse hyperemia are challenging to differentiate from those caused by early infection and marrow infiltration and particularly difficult to differentiate from those due to complex regional pain syndrome, which results in similar hyperemia and osteopenia. Complex regional pain syndrome should be diagnosed on the basis of clinical criteria, as the imaging findings are nonspecific (49).…”