1st MTP pain was a prominent feature in people with gout .
Imaging features were common at the 1st MTP including the double contour sign , tophi and erosions .
Conclusions 1st MTP acute arthritis is highly prevalent in people with gout and has a substantial impact on patient-reported pain and disability .
Gout affects the structure and function of the 1st MTP .
Microscopic and imaging studies have demonstrated crystal deposition and joint damage at the 1st MTP in people with gout
Background The aim of this review was to qualitatively synthesis e studies that have investigated characteristics of the  first metatarsophalangeal joint ( 1st MTP )  in gout and to undertake a meta- analysis to estimate the average prevalence of acute 1st MTP arthritis across studies in people with gout .
Ultrasonography shows disappearance of monosodium urate crystal deposition on hyaline cartilage after sustained normouricemia is achieved
This study aim ed at determining whether lowering serum urate ( SU ) to less than 6 mg/dl in patients with gout affects ultrasonographic findings . Seven joints in five patients with monosodium urate ( MSU ) crystal proven gout and hyperuricemia were examined over time with serial ultrasonography . Four of the five patients were treated with urate lowering drugs ( ULDs ) ( allopurinol , n = 3 ; probenecid , n = 1 ) . One patient was treated with colchicine alone . Attention was given to changes in a hyperechoic , irregular coating of the hyaline cartilage in the examined joints ( double contour sign or “ urate icing ” ) . This coating was considered to represent precipitate of MSU crystals . Index joints included metacarpophalangeal ( MCP ) joints ( n = 2 ) , knee joints ( n = 3 ) , and first metatarsophalangeal ( MTP ) joints ( n = 2 ) . The interval between baseline and follow-up images ranged from 7 to 18 months . Serial SU levels were obtained during the follow-up period . During the follow-up period , three patients treated with ULD ( allopurinol , n = 2 ; probenecid , n = 1 ) achieved a SU level of < 6 mg/dl . In two patients , SU levels remained above 6 mg/dl ( treated with allopurinol , n = 1 ; treated with colchicine , n = 1 ) . At baseline , the double contour sign was seen in all patients . In those patients who achieved SU levels of < 6 ml/dl , this sign had disappeared at follow-up . Disappearance of the double contour sign was seen in two knee joints , two first MTP joints , and one MCP joint . In contrast , disappearance of the double contour sign was not seen in patients who maintained a SU level ≥7 mg/dl . In one patient treated with allopurinol  , SU levels improved from 13 to 7 mg/dl during the follow-up period . Decrease , but not resolution of the hyperechoic coating was seen in this patient . In the patient treated with colchicine alone , SU levels remained > 8 mg/dl , and no sonographic change was observed . In our patients , sonographic signs of deposition of MSU crystals on the surface of hyaline cartilage disappeared completely if sustained normouricemia was achieved . This is the first report showing that characteristic sonographic changes are influenced by ULDs once SU levels remain ≤6 mg/dl for 7 months or more . Sonographic changes of gout correlate with SU levels and may be a non-invasive means to track changes in the uric acid pool . Larger prospect i ve studies are needed to further assess these potentially important findings
1st MTP pain was a prominent feature in people with gout .
Imaging features were common at the 1st MTP including the double contour sign , tophi and erosions .
Conclusions 1st MTP acute arthritis is highly prevalent in people with gout and has a substantial impact on patient-reported pain and disability .
Gout affects the structure and function of the 1st MTP .
Microscopic and imaging studies have demonstrated crystal deposition and joint damage at the 1st MTP in people with gout
Background The aim of this review was to qualitatively synthesis e studies that have investigated characteristics of the  first metatarsophalangeal joint ( 1st MTP )  in gout and to undertake a meta- analysis to estimate the average prevalence of acute 1st MTP arthritis across studies in people with gout .