The TRAC-PS dual radius total knee arthroplasty : Disappointing medium and long terms results.

The TRAC prosthesis is a dual radius, mobile bearing, posterior stabilized prosthesis, to increase stability by optimizing contact area and control wear using a mobile polyethylene. Between February 1995 and January 2000, a single surgeon performed a continuous series of 85 TRAC-PS TKAs in 85 patients at the University Hospital Brussels. A retrospective review on patient charts was performed. Patients available were scored clinically using the Knee Society Score, WOMAC osteoarthritis index, SF 36 and a Visual Analogue Scale for pain. 43 patients had died at time of evaluation, three were unavailable for examination due to bad general health and five were lost to follow up. The remaining 35 patients were examined with a mean follow-up of 13 years. The mean age of the patients at follow up was 83 years. The mean WOMAC score was 78,4(SD 17,9). The mean Knee Society Score was 86.8(SD 8,4) clinical and 42,6(SD 28) functional. The mean range of flexion was 105°. The mean SF-36 score was 59,8(SD 15,4). The VAS for pain was 6(SD 9). With revision (8 cases) as endpoint, survival rate of the prosthesis was estimated to be 92% at 13 years. Twenty-three Serious Adverse Events (28%) in 17 patients, related to the prosthesis were registered in this patient group. Long term results of this prosthesis were satisfying but a large number of serious adverse events led to abandonment of the TRAC-prosthesis.

The Oxford unicompartmental knee prosthesis: an independent 10-year survival analysis.

One hundred forty-nine medial prostheses were implanted in 140 patients between 1988 and 1996. After a mean of 67 months 28 patients had died, without the need for revision. Seventeen prostheses were lost to follow-up. Revision surgery using a total knee prosthesis was performed in 16 cases. In four others, a lateral prosthesis was implanted subsequently to a medial one. One of these four was revised to a total knee prosthesis 6 years later. In another four cases, late complications of the meniscal bearing were treated with replacement of this bearing. The surviving prostheses were seen back after a mean of 126 months. The cumulative survival rate at 10 years was 82% for the whole population and 84% when knees with a previous high tibial osteotomy were excluded. Since these results compare poorly to the survival of total knee arthroplasty, this prosthesis is not the first-choice implant. Because it preserves a maximum of bone stock and is revised to a total prosthesis almost without difficulty, it is the first-choice implant for medial unicompartmental osteoarthritis in patients younger than 65. Further research is mandatory to confirm that this prosthesis very rarely needs revision in patients older than 75. It should not be used in osteotomized knees.

Is acute compartment syndrome avoidable?

Complete absence of acute compartment syndrome was observed in a consecutive series of 966 tibial fractures in African patients of diverse ethnic groups, reviewed retrospectively at our institution. Considering the incidences reported in the literature, we should have experienced between 22 and 86 cases of acute compartment syndrome. The purpose of this prospective study was to confirm these findings and at the same time to look for possible explanations for this unexpected observation. During a period of one year and four months, 257 tibial fractures were prospectively analyzed for clinical signs and late sequelae of acute compartment syndrome. In 156 of these patients, presenting 158 fractures of the tibia, the pressure in the anterior compartment was systematically measured. No single case of compartment syndrome was diagnosed in this series, and no late sequelae of acute compartment syndrome were noted. The hypothesis we forward for total absence of acute compartment syndrome is the favourable effect of the continuously high surrounding temperatures on safeguarding the arteriovenous pressure gradient and lowering the vascular resistance. We suggest that further investigation should be carried out to study this hypothesis.

The use of primary total hip arthroplasty in university hospitals of the European Union.

Current practice in primary total hip replacement was investigated by postal survey in 125 university hospitals of the European Union (EU). Most hospitals (78.4%) use a hip register and implant cemented as well as uncemented stems (72.0%) and cups (68.8%). In Scandinavian & Anglo-Saxon countries, 42.9% of the departments implant cemented stems in all their patients, and 16.7% implant cemented cups in all their patients. In these countries, modern cementing techniques are commonly used and therapeutic choices are strongly influenced by hip registers. In Southern Europe, cemented cups have been abandoned in 31.1% and modern cementing techniques are less common. Benelux & Germanic countries have a practice in between. Three cemented (Exeter, Charnley, Lubinus) and three uncemented stems (Zweymüller, ABG, Bi-contact) represent 41.9% and 25.3% of stem types in use. Most departments (70.4%) have adopted alternative bearings. Ceramic-ceramic and metal-metal are both used in almost half of the hospitals. Metal-polyethylene has been abandoned in 15.2%. These trends are taught to new generations of surgeons in the EU and could become common practice in a near future.

Socioeconomic aspects of total hip arthroplasty. A one-year survey in a Belgian university hospital.

We prospectively analysed hospital stay, discharge policy, hospital cost and postoperative recovery of 102 consecutive total hip arthroplasties performed in a Belgian university hospital during a one-year period starting in October 2001. Of the independent patients, 87.4% regained independence after 6 weeks and 19.6% used rehabilitation units. Preoperative residence, hip function and mental scores were the best predictors for postoperative independence. Average hospital stay was 14.4 days and hospital cost 9,500 Euros. Hospitalisation represented over 50% of hospital cost and hip implants between 16.1 and 25.6% depending on prosthesis type. Complications and discharge to a rehabilitation unit increased hospital stay and cost. Six months after surgery, functional hip scores as well as WOMAC, mental and physical SF-12 scores improved significantly. Surgical techniques and faster rehabilitation programs, reducing needs for rehabilitation units and allowing earlier return to independence, are probably the best ways to control the cost of total hip arthroplasty in Belgium.