Taper corrosion in modular hip prostheses: analysis of serum metal ions in 19 patients.

Recently, concerns have been raised about the use of metal-on-metal (MoM) implants. This has led to the recall of several resurfacing and large-diameter total hip arthroplasties (THA). Any MoM interface can be the cause of metal debris and adverse tissue reactions. We analyzed serum metal ions and HOOS scores in 19 of 306 patients treated with a THA with modular neck section. The only MoM interface in this particular implant is the taper between the neck and the stem. The articulating surface consists of a ceramic-on-polyethylene or ceramic-on-ceramic interface. As such, this study looks at the metal ion production from the modular neck section. One of 306 implants needed revision at 52-month follow-up because of an adverse reaction to metal debris (ARMD).

Functional and radiographic short-term outcome evaluation of the Visionaire system, a patient-matched instrumentation system for total knee arthroplasty.

Patient matched instrumentation is a new operative tool in the field of total knee arthroplasty. Custom made cutting blocks are designed to perform distal femoral and tibial bone cuts according to a pre-operative planning. This study evaluates the Visionaire system of Smith & Nephew. Thirty-one patients, operated with the Visionaire technique, were compared to an equal control group for different clinical and radiographic outcome parameters. Between both groups, no statistical significant difference could be found in post-operative pain, satisfaction, functional outcome, hospital stay, blood loss, radiographic alignment and precision of bone cuts. Only tibial plateau backslope can be created with more precision in the Visionaire group. But there was a statistical significant difference for residual flexion deformity after a mean follow-up time of 200 days.

Functional and radiographic medium-term outcome evaluation of the Humerus Block, a minimally invasive operative technique for proximal humeral fractures.

BACKGROUND: Conservative treatment of severe displacement of proximal humeral fracture fragments yields bad functional results, but open operative techniques have a high risk of avascular necrosis of the humeral head. We performed a medium-term outcome evaluation of the Humerus Block (Synthes, Oberdorf, Switzerland), a minimally invasive technique used in selected patients with proximal humeral fractures, to investigate the functional and radiographic outcome. MATERIALS AND METHODS: Of 47 patients operated on with the Humerus Block, 34 with a minimum follow-up of 30 months and a mean follow-up of 4 years and 4 months, were invited for interview, radiographic evaluation, and functional analysis by the Constant, Disabilities of Arm, Shoulder and Hand (DASH) and the University of California, Los Angeles (UCLA) scorings. Paired t test was used to investigate equivalence of the geometric mean scores of the trauma and control arm, for the scores of the functional analyses, and for the scores for mobility of the shoulder. RESULTS: Scorings and clinical examination showed that 85% of shoulder function and motion were preserved compared with the control arm. Radiographic evaluation showed very good healing and positioning of the fracture fragments, and only 10% developed avascular necrosis of the humeral head. CONCLUSIONS: With very satisfied patients; good clinical, functional, and radiographic outcomes; a short hospital stay; few complications; a reduced cost of implant; and a low incidence of avascular necrosis, this technique is a valuable alternative for operative treatment of proximal humeral fractures.