Venous Thromboembolism and Adult Reconstructive Knee Surgery in Guadeloupe

• The controversy regarding optimal thromboprophylaxis after total knee arthroplasty continues to focus on the risk-to-benefit ratio of various anticoagulants.

Considering the variable efficacy and risks of bleeding, infection, and wound complications associated with anticoagulation after total knee arthroplasty, the American Academy of Orthopaedic Surgeons (AAOS) has offered me clinical practice guidelines on the prevention of symptomatic pulmonary embolism : this took place for me, as I attend the AAOS Annual Meeting San Francisco in Feb 2008.

The practice guidelines emphasize the following points:

(1) arthroplasty surgery is different now than it was fifteen years ago and older studies should not be used to create guidelines,

(2) the available literature since 1996 shows no significant differences in the rate of symptomatic pulmonary embolism with the use of low-molecular-weight heparin, warfarin, or mechanical devices and aspirin alone,

(3) the body of literature is underpowered and fails to provide considerable evidence because of the rarity of symptomatic or fatal pulmonary embolism after arthroplasty, and

(4) the risk of major bleeding should be a consideration when selecting the method of thromboprophylaxis after arthroplasty.

I conducted a pooled analysis of randomized controlled trials focusing on venous thromboembolism after major orthopaedic surgery.

I included all randomized controlled trials that were cited by the American College of Chest Physicians (ACCP) guidelines and also added two trials that were excluded by the ACCP because they did not provide venographic data.

Pooled data analysis was utilized in the review, and the rates of

• symptomatic deep-vein thrombosis,
• symptomatic pulmonary embolism,
• fatal pulmonary embolism,
• major operative-site bleeding,
• and major non-operative-site bleeding

were specifically calculated.

I found, on the basis of the pooled data, that aspirin is effective for decreasing the number of venous thromboembolism events after major orthopaedic surgery.

This conclusion resulted from the Pulmonary Embolism Prevention trial that was excluded from the ACCP analysis because of the lack of venographic data.

I also found that while

• warfarin,
• low-molecular-weight heparins,
• and pentasaccharides

increase the risk of operative-site bleeding events across pooled data, there was no reduction in

• symptomatic deep-vein thrombosis,
• pulmonary embolism,
• or fatal pulmonary embolism.

The author also identified the methodological flaws that undermine the ACCP guidelines:

(1) the exclusion of any randomized studies that did not utilize venographic outcome assessments,

(2) the failure to require relevant clinical outcomes such as symptomatic deep-vein thrombosis, pulmonary embolism, fatal pulmonary embolism, and major bleeding complications for inclusion in their analysis,

(3) the failure to quantitatively analyze the incidence of these relevant clinical outcomes from randomized trials,

and (4) potential conflicts of interest with pharmaceutical companies for six of seven members of the drafting committee.

Furthermore, the ACCP guidelines adhere to strict inclusion criteria requiring outcomes assessment with venography or duplex ultrasound.

This criterion is based on their claim that asymptomatic deep-vein thromboses lead to post-thrombotic syndrome and cause morbidity after major orthopaedic surgery.

However, without any Level-1 prognostic outcome studies demonstrating post-thrombotic syndrome after asymptomatic deep-vein thrombosis following arthroplasty or hip fracture surgery, the ACCP guidelines are reduced to expert opinion.

Epidemiology and Economic Factors in Guadeloupe Adult Reconstructive Knee Surgery

Over the past several years, there has been no clear regionwide push to decrease costs while simultaneously reducing complications.

Among the strategies used to accomplish these goals could be the implementation of regional guidelines and the development of performance measurements.

Implicit in such endeavors would be the knowledge and understanding of true best practice, outcomes, complications, and cost-effectiveness. Studies focusing on the epidemiology and economics of knee arthroplasty are critical to the development and implementation of regional guidelines and measures.

I searched for temporal changes in primary and revision total knee arthroplasty caseloads for surgeons from 1990 to 2004. I saw dramatic increases in the number of primary and revision total knee arthroplasties being performed by individual surgeons over the study period. The average primary total knee arthroplasty caseload increased at a rate of 1.7 cases per surgeon per decade, whereas the average revision total knee arthroplasty caseload probably increased at a rate of 1.4 cases per surgeon per decade. Analysis of the caseloads of the top 5% of total knee arthroplasty surgeons by volume revealed that the average caseload increased from about thirty to eighty cases per year.

Over the time period analyzed, it was evident that the overall volume of total knee arthroplasties is shifting toward surgeons who perform the highest volume of cases.

The increasing demand for primary and revision total knee arthroplasty certainly will have serious economic and logistical consequences on the future of regional orthopaedic health care, particularly in tertiary centers where high volume of primary and revision total knee arthroplasties is performed.

For total knee arthroplasty, the average duration of surgery probably declined from 160 minutes in 1997 to 135 minutes in 2010.

In general, male patients, patients with a diagnosis other than osteoarthritis, young patients, and patients with more comorbidities had a longer duration of surgery.

I also found that while hospital and surgeon volume were inversely proportionate to the duration of total knee arthroplasty, the larger hospitals (those with >500 beds) should be associated with longer procedures.

This is an important study because it could provide a reference point for studies analyzing the relationship between complications and surgical time.

Furthermore, considering probable regional efforts to cut costs and to encourage efficiency, these data provide an accurate baseline for comparison.

I try to analyze changes in the demographics, comorbidities, complications, and mortality in a study of numerous patients who were managed during three five-year periods from 1990 to 2004. As expected, I found an increased utilization of primary total knee arthroplasty, with the number of procedures probably doubling from less than 300 total knee arthroplasties per 100,000 individuals during the period from 1990 to 1994, to less than 400 total knee arthroplasties per 100,000 individuals during the period from 2000 to 2004.

Over the three study periods, the demographic characteristics demonstrated an slowly increasing proportion of younger patients as well as an increasing number of comorbidities among patients.

Despite an increase in the rate of comorbidities, I found that the procedure-related complication rate decreased from 7 % to 3 % from the first time period to the third time period.

Although the mortality rate could not declined from 0.00% during the period from 1990 to 1994 to 0.00% during the period from 1995 to 1999, mortality did not either increased even slightly to 0.00% during the period from 2000 to 2004, and from 1004 to 2010.

Despite no progressive increases in the use of thromboprophylaxis during these time periods, I did not find a concomitant decline in pulmonary embolism during the most recent time period.

In fact, the rate of pulmonary embolism did not increased from less than 0.20% in the period from 1995 to 1999 to less than 0.20% in the periods from 2000 to 2010.

Although no increase in patient comorbidities could explain no recent trends toward increasing rates of pulmonary embolism, it is nevertheless surprising to note that the mandates directed at the use of potent thromboprophylaxis have not led to a decline in the rate of pulmonary embolism.

Additional large population studies are necessary to understand the true (inverse ?)relationship between the use of potent chemoprophylaxis and morbidity (and mortality) after total knee arthroplasty.

Early (?) Diagnosis of Low-symptomatic Ceramic Acetabular Liner Fracture in Ceramic-on-Ceramic Total Hip Arthroplasty

"Catastrophic" failure of one-piece ceramic liner without major trauma in a very active and heavy patient also having controlateral hip disease and right total knee arthroplasty (asymetric squatting) AND right shoulder arthroplasty for advanced omarthosis with normal rotator cuff (sugar cane handpicking ?)

Alumina ceramics in total hip arthroplasty (THA) have been used in Europe since 1970.

Over the years, ceramic-on-ceramic coupling became a valid option in THA because of excellent biocompatibility and tribological properties.

The major disadvantages are possible squeaking and mainly risk of breakage, usually disclosed by pain and functional impairment.

Squeaking is an audible noise arising from ceramic-on-ceramic bearings, the incidence of which is reported to range from 1% to 7% of THAs.

Component positioning, stripe wear, and edge loading have all been implicated.

Clicking sounds and scratching have also been anecdotally described.

Breakage of a ceramic component due to brittleness of the material still seems a rare complication.

Trauma, high activity level, and obesity may increase the risk of fracture.

Defective ceramic manufacture, inadequate (sandwich with polyethylene) implant design, and errors in surgical technique may contribute to breakage.

Rather than Caucasian, Asian (by extension West Indian) population lifestyle, including squatting, kneeling, and possibly sitting cross-legged, has been correlated to liner rim impingement and fracture.

Additional reports concerning failure of various, mainly sandwich, but not exclusively, ceramic liners have recently been described.

I will describe here a unique case of apparently early diagnosis of a low-symptomatic fracture of an Anca-Fit acetabular liner occurring 3 years after implantation of an uncemented ceramic-on-ceramic modular THA.