{"id":13037,"date":"2015-05-20T08:05:41","date_gmt":"2015-05-20T08:05:41","guid":{"rendered":"http:\/\/healthmedicinet.com\/news\/thumb-hypoplasia-current-concepts\/"},"modified":"2015-05-20T08:05:41","modified_gmt":"2015-05-20T08:05:41","slug":"thumb-hypoplasia-current-concepts","status":"publish","type":"post","link":"http:\/\/healthmedicinet.com\/news\/thumb-hypoplasia-current-concepts\/","title":{"rendered":"Thumb hypoplasia: current concepts"},"content":{"rendered":"<p>This presentation discusses an updated classification of thumb hypoplasia which allows<br \/>\n         greater relevance of comparison of surgical results; advises upon the indications<br \/>\n         for specific surgical techniques; presents some detail of many but not all surgical<br \/>\n         techniques; and discusses methods of assessment of outcomes following surgery.\n      <\/p>\n<p>The Blauth classification of hypoplastic grades 1-5 is based on the work of Mueller<br \/>\n         who proposed the concept of an increasing severity of hypoplasia of all thumb components,<br \/>\n         soft tissue and bone, with increasing severity of insult. Manske and others have sub-divided<br \/>\n         grade 3 in an attempt to compare like with like but this classification does alter<br \/>\n         the integrity of the Blauth system which distinguishes between grades 2 and 3 by the<br \/>\n         presence or absence of the proximal metacarpal. My proposed classification maintains<br \/>\n         the integrity of Blauth\u00e2\u20ac\u2122s classification, sub-dividing within grade 2. Grade 2A is<br \/>\n         of mild nature with first web deficiency, uniaxial MCP joint instability and hypoplasia<br \/>\n         of intrinsic muscles, each of which may require reconstruction through local flaps<br \/>\n         in the first web, ulnar collateral ligament reconstruction and an opposition transfer.<br \/>\n         Extrinsic anomalies may be present but do not deserve attention. Grade 2B is moderate<br \/>\n         in nature and in this instance extrinsic anomalies which require reconstruction are<br \/>\n         present as is global MCP joint instability. An FDS transfer is the most appropriate<br \/>\n         opposition transfer as the tails of the tendon may be used for reconstruction of ulnar<br \/>\n         and radial collateral ligaments. A palmar plate advancement may assist in hyperextension<br \/>\n         of the MCP joint. A more extensive first web plasty with skin grafting may be necessary.<br \/>\n         Grade 2C is of severe nature with severe global MCP joint instability as demonstrated<br \/>\n         by the \u00e2\u20ac\u0153elephant\u00e2\u20ac\u2122s trunk\u00e2\u20ac\u009d sign. Fusion of the MCP joint is appropriate but this does<br \/>\n         have the problem of increasing the length of the lever arm, placing greater stress<br \/>\n         across an unstable CMC joint. Furthermore, it shortens the digit, places the growth<br \/>\n         plate at risk and it may be possible to obtain a chondrodesis only if the epiphysis<br \/>\n         has not ossified. Regardless, it is almost impossible to reconstruct such joints with<br \/>\n         soft tissue procedures alone. The CMC joint is also inadequate, being unstable or<br \/>\n         immobile. Most current classifications do not attend to this complex problem. A radiological<br \/>\n         \u00e2\u20ac\u0153pencil sign\u00e2\u20ac\u009d is indicative of the severe underdevelopment of the CMC joint, which<br \/>\n         may respond to a soft tissue reconstruction. However, occasionally pollicisation may<br \/>\n         give superior outcomes for the severe grade 2C hypoplasias.\n      <\/p>\n<p>Distinction between grades 3A and 3B on the basis of the amount of the metacarpal<br \/>\n         absent, the proximal third in 3A and the proximal two-thirds in 3B, allows a comparison<br \/>\n         of surgical results when one decides to reconstruct these severely hypoplastic thumbs.<br \/>\n         Results of reconstruction tend to be improved when there is more to work with. For<br \/>\n         the same reasons the grade 4 thumb is less likely to be as functional as a grade 3A<br \/>\n         or 3B thumb when reconstruction of the floating digit is attempted.\n      <\/p>\n<p>Pollicisation remains the preferred option for grades 3, 4 and 5, and occasionally<br \/>\n         for grade 2C. A whole toe transfer is an option for reconstructing a grade 5 thumb<br \/>\n         when a determination to obtain five digits is absolute.\n      <\/p>\n<p>Assessment of results following reconstruction of the paediatric hypoplastic thumb<br \/>\n         is difficult. An assessment scale is offered which incorporates components of scales<br \/>\n         previously described by Percival and Japanese authors, not only following reconstruction<br \/>\n         of the hypoplastic thumb but also following reconstructions of thumb duplications.<br \/>\n         Although such an assessment scale contains some flaws, it does provide an objective<br \/>\n         basis from which pre- and post-operative comparisons can be made and comparisons between<br \/>\n         surgical results of one may be compared with those of others. To achieve this, it<br \/>\n         is necessary to begin with a classification which at least allows comparison of like<br \/>\n         with like.\n      <\/p>\n","protected":false},"excerpt":{"rendered":"<p>This presentation discusses an updated classification of thumb hypoplasia which allows greater relevance of comparison of surgical results; advises upon the indications for specific surgical techniques; presents some detail of many but not all surgical techniques; and discusses methods of assessment of outcomes following surgery. The Blauth classification of hypoplastic grades 1-5 is based on [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[],"class_list":["post-13037","post","type-post","status-publish","format-standard","hentry"],"_links":{"self":[{"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/posts\/13037","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/comments?post=13037"}],"version-history":[{"count":0,"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/posts\/13037\/revisions"}],"wp:attachment":[{"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/media?parent=13037"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/categories?post=13037"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/healthmedicinet.com\/news\/wp-json\/wp\/v2\/tags?post=13037"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}