This research was done in the Asan Medical Center in Seoul. We performed a prospective study to assess clinical outcomes, complications and survival of prostheses in a consecutive series of 278 knees receiving NexGen legacy posterior stabilised (LPS) – Flex total knee replacement (TKR) between May 2003 and February 2005. The mean follow-up period was 3.8 years (3.0 to 4.8), and 259 knees (93.2%) were followed for an adequate interval. Annual follow-ups showed improvement in the Knee Society scores (paired t-test, P< 0.05). At the latest follow-up, the mean maximal flexion was 135° (110° to 150°). Two knees showed radiolucency but revision was not required as there were no significant symptoms. Revision was required in one case due to prosthetic infection, but no prosthesis-related revisions were required. There were no complications such as patellofemoral pain, wound healing problems, dislocation or instability during deep flexion postoperatively. The estimated survival rate at 4 years with revision for any reason and prosthesis-related problems were 99.6% and 100% respectively (life-table method). This relatively large TKR study indicates that LPS-Flex system provides excellent medium-term outcomes and seems to warrant ongoing evaluation to confirm the long-term durability and functioning of the implant afterward.

To evaluate the effectiveness of core decompression using the tantalum trabecular metal system for treatment of an early stage osteonecrosis of femoral head in minimum 1 year to maximum 5 years follow-up.

From January 2003 to August 2007, 36 patients in 46 cases underwent core decompression using the tantalum trabecular metal system. The ARCO classification system was used. Retrospective analysis was done. The conversion to total hip arthroplasty due to aggravating hip pain was defined as a clinical failure.

With the higher stage of ARCO classification and more lateral location of lesion, the conversions to total hip arthroplasty would be increased. The better outcome was noted with lower stage of ARCO classification and more medial location of the lesion.

The higher stage of ARCO classification and more lateral position of lesion, the failure rate of the tantalum trabecular metal system increases. The most important thing is to detect early stage of osteonecrosis of femoral head. The tantalum trabecular metal system is considered as a useful treatment of osteonecrosis of femoral head with lower stage of ARCO classification and medial location of lesion.