ATYPICAL KNEE ALGODYSTROPHY - REPORT OF 2 CASES WITH PARTIAL FORMS

Algodystrophy is a common entity which may present in many clinical co ntexts. Its early diagnosis and therapy are of great prognostic intere st. Apart from the typical complete forms there are some other atypica l forms, such as partial knee algodystrophy, of difficult diagnosis. I ts inclusion in the differential diagnosis of gonalgia occurring in pa tients attended under many medical specialties is therefore necessary. Two atypical cases of knee algodystrophy in its partial form are repo rted. One of these cases relapsed at the heterolateral knee after 18 m onths of the initial presentation; this second episode was also a part ial form, a fact which we have not seen reported. The reported cases a re here discussed and the scarce literature is reviewed, commenting on the difficulty of the early diagnosis compared with other entities wh ich may mimic the clinical picture, radiological and scanning features of algodystrophy, such as aseptic osteonecrosis or stress fracture. T he diagnostic algorithm is discussed, pointing to the usefulness of ma gnetic resonance (MR) in difficult cases to rule our other entities wh ich would entail different therapeutic modalities.