Surgical restoration of prehension by a pollici -digital pinch in high level tetraplegia

In 1975, Erik Möberg laid the foundations of functional surgery ofthe upper limb in high level tetraplegia. He described the “KeyGrip” or passive termino-lateral pinch with tenodesis activated bywrist extension, allowing restoration of a pollici-digital prehensionin high level tetraplegia. The simplicity of the surgical technique asdescribed by Möberg does not however permit it to be adapted to allsituations. Thanks to our 25 year old experience in functional surgeryof the upper limb in tetraplegia, we have modified this basicconcept. Restoration of this termino-lateral pollici-digital pinchmust take into account : -not only its closing but also opening amplitude;-not only the level of the neurological injury (Groups GIand GII of the international classification), but also the extent of thelesional medullary segment (presence or absence of an active sublesional segment);- and lastly the wishes of the patient (strong pinchor large pollici-digital opening).In order to perform a “Key Grip” the author distinguishes :- -its activation : active wrist extension (GII) or brachio-radialistransfer on the ECRB and ECRL (GI);- -thumb positioning depending on the extent of the lesional medullarysegment. When the thumb is badly positioned, in case ofa large lesional segment, the authors prefer positioning of thethumb column by tenodesis, according to a personal technique,rather than a trapezo-metacarpal arthrodesis.The results, in 45 cases, are analysed following activation of pollicidigitalpinch closing and thumb positioning.The results of each of these methods are explained to the patientand the “Key Grip” is performed “à la carte” following the patient’swishes.