Hemiarthroplasty, a Costly Choice?

In an economic downturn as severe as the one we are presently experiencing, every purchase is subject to scrutiny. This is as true in orthopedics as it is in the car market. In a comparison of the costs of a hemiarthroplasty with its alternative of a total hip arthroplasty (THR), we found that, using the PearlDiver Record database, hemiarthroplasty procedures surprisingly don’t stack up!

Here is the story. When it comes to repairing hips, most patients think that “less is better.” They do not want any more of their body replaced than is necessary. This tilts the scale toward a hemiarthroplasty because, in this procedure, only the femoral components are replaced; recovery time logically should be quicker, thus reducing complications, hospitalization time, and the price tag.

In 2006 more than 250,000 Americans had a hemiarthroplasty hip procedure. That was 20,000 more than those who had the standard total hip arthroplasty. Combined, the two procedures accounted for nearly half a million hip surgeries.

Table 1: U.S. Hip Procedures

To assess the value of the hemiarthroplasty versus its primary alternative—THR in private pay patients—PearlDiver analysts compared two key elements: price and conversion/revision rates. A sample set from each group was selected consisting of 1,350 hemiarthroplasty patients and 5,250 THR patients under the age of 65. All members of both groups had their procedures in 2004, thus allowing for three post-procedural years to assess any required conversions or revisions.

The Price Tag
Each procedure comes with two price tags: the physician’s charge and the hospital’s charge. The average physician’s charge for the hemiarthroplasty in our sample set of patients was $3,530. When the average hospital charge of $60,769 for this group is added in, the total average cost for a hemiarthroplasty procedure was slightly over $64,000.

For a THR, the average physician’s charges in our sample set were $4,623 while the average hospitalization charge was substantially lower than hemiarthroplasty at $42,937. The total charge for the THR was $47,560, or a savings of around $16,700 less than the hemiarthroplasty.

Since 2004 when the patients of our sample set had their procedure, the charges associated with THR procedures have increased a dramatic $7,375. Even with this increase, current charges for the hemiarthroplasty procedure still amount to a stunning $8,083 more than the THR procedure.

Table 2:  Average Procedure Charges to Privately Insured Patients

What accounts for this discrepancy? The greatest difference between the patients for the two procedures is the diagnosis prior to treatment. Although both procedures have similarities, over 70% of the patients who received the hemiarthroplasty were diagnosed with one or more fractures. This compares to only 5% of the THR patients. The result is a potentially longer hospital stay for hemiarthroplasty patients because of complications from trauma.

According to the Agency for Healthcare Research and Quality’s Healthcare Cost and Utilization Project, the mean length of hospital stay for a THR patient was 4 days while the average length of stay for a hemiarthroplasty patient was 6.6 days.

If we assume that a longer length of stay is required for all 70% of the hemiarthroplasty patients who suffered a fracture, then the hospital charges on a per-day basis are not out of line. When we break down the average per-day hospital charges for the hemiarthroplasty patients, they come to $9,096 versus the average charge per day for a THR of $10,734. If trauma were not involved and a hemiarthroplasty patient only required four days in the hospital, the charges would be $6,553– in favor of hemiarthroplasty—rather than a THR. However should a patient suffer a facture and require the average of 6.6 days in the hospital, the difference would be a startling $10,813.

Are fractures driving up the cost of hemiarthroplasties? To answer the question, PearlDiver filtered out of its patients' sample those diagnosed with a fracture prior to having the procedure. The answer was a resounding NO. Of the patients having the procedure without a prior fracture diagnosis, the average hospital charges increased to $87,985, a figure that does not include the physician charges. It is not the primary diagnosis that is driving the length of hospital stay and thus increased hospitalization charges. It is, instead, a function of the procedure itself.

Value

Does a higher price tag represent greater value to the patient? If so, then the hemiarthroplasty should provide better results for a patient than a total hip replacement. Using conversion and revision codes on the procedures performed in 2004, we put this assumption to the test. If the high price tag procedure provided greater benefits to the patient, we should see fewer conversions in the following three years to total hip arthroplasty and fewer revisions on hemiarthroplasty patients than on those patients who received a total hip arthroplasty.

Table 3: Three Year Follow-Up Results

Table 3 shows the results through 2007. Of the patients who underwent a total hip arthroplasty, the total revision rate was 3%. However, the revision/conversion rate for the hemiarthroplasty patients was three times that of the total hip arthroplasty patients. Even more surprising was the rate at which this took place among age groups. While 7% of the hemiarthroplasty patients age 55 to 64 required a revision/conversion, a full 16% of patients age 35 to 44 required a revision/conversion. These results show that hemiarthroplasty patients are not receiving a level of benefit comparable to a total hip arthroplasty or commensurate to the price difference between the two options.

Table 4 shows the three-year follow-up results for male patients. The age group with the highest rate of revision/conversion is age 35 to 44 with 21%. This is followed by patients age 25 to 34 who have a 14% revision/conversion rate. This is exceptionally high when compared to THR patients who, in any age group under the age of 65, experience at most a 3% revision rate.

Table 4: Three Year Follow-Up Male Patients

Female patients have experienced significantly different results from male patients. In both hemiarthroplasty patients and THR patients, the total rate of revision/conversions was higher in females than in males. Not only is the rate higher but the trend is different among age groups between genders.

Male hemiarthroplasty patients experienced a revision/conversion rate of 8% while female patients fared worse at 10%. Female patients’ highest revision/conversion rate was in the age group of 44 to 54, considerably older than the high point for male patients.

Table 5: Three Year Follow-Up Female Patients

Between genders, with the exception of patients age 0 through 24, female THR patients fare worse in every age category than their male counterparts. Regardless of procedure, hemiarthroplasty or THR, female patients have a greater chance of later requiring revision.

Still, as the numbers indicate, the likelihood of revision/conversion occurring is far greater for both male and female patients with a hemiarthroplasty when compared to the alternative of a THR. Because there is less benefit for the patient, from an economic standpoint, charges for the hemiarthroplasty procedure should be lower than the charges for a THR. But this is not the case, making hemiarthroplasty a costly choice.