TomoFix HTO Small Stature (Asian Version)

Osteoarthritis due to varus deformity of the knee is common in Asian countries. For instance, it is said that 7 million patients need treatment for knee osteoarthritis in Japan. High-tibial osteotomy (closed-wedge or dome) used to be a common procedure for these patients. However, the treatment trend shifted to total knee arthroplasty or unicompartmental knee arthroplasty because of the complications and relatively high rate of failures of the conventional high-tibial osteotomy. Although there is a renewed interest in medial open-wedge high-tibial osteotomy with the TomoFix, the plate was too large for the small stature female patients in Asia. Therefore, the TomoFix HTO small stature (Asian version) was developed by the Knee Expert Group in collaboration with the Asian Pacific Surgery group.

This new plate was developed taking into consideration the requests of knee surgeons in Japan. Based on CT scans of the typical Japanese patient (60-year-old female weighing less than 60 kg), the plate widths at head and shaft, plate radius, and the radii surround were reduced. This improved anatomical fit for the typical small stature patient will decrease pain due to minimizing the risk of complications with wound closure or irritation of soft tissue and skin. High-tibia osteotomy (TomoFix HTO) small stature is indicated for all open-wedge osteotomies on tibiae in small patients with less than 65 kg without postoperative restriction. Otherwise, the small stature version has the same indications as the standard plate TomoFix HTO.

65-year-old female. Osteoarthritic patient complaining of medial knee pain of her left knee.

Case provided by Takeshi Sawaguchi, Toyama, JP

Follow-up in this case is short, because the TomoFix small only became available in August 2008.

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