Mileage Varies for Different Hip Surgery Approaches

Most common types of hip arthroplasty achieve similar clinical improvements, a new meta-analysis indicated, but one particular approach appeared to fall short.

With data combined from 63 randomized trials with a total of 4,859 patients, pairwise comparisons showed that seven of eight approaches evaluated achieved similar levels of improvement in the hip score and pain, according to Bin Wang, MD, PhD, of Zhejiang University School of Medicine in Hangzhou, China, and colleagues.

The outlier was the direct lateral approach (DLA), for which hip score improvements were smaller than for the other surgical types, the group reported in JAMA Network Open. For six of the comparisons between DLA and the other approaches, the difference was statistically significant and ranged from 3.00 to 5.00 points on the measure’s 100-point scale. The seventh comparison, with the 2-incision approach, yielded a difference of 5.38 points that just missed statistical significance. DLA was also associated with greater blood loss than the others.

In addition to DLA and the 2-incision approach, the researchers looked at the direct anterior approach (DAA), minimally invasive direct lateral approach (MIS-DLA), minimally invasive anterolateral approach (MIS-ALA), posterior approach (PA), minimally invasive posterior approach (MIS-PA), and supercapsular percutaneously assisted total hip arthroplasty (SuperPath).

When Wang and colleagues examined hospitalization time, reported in 33 of the included trials, SuperPath procedures were the shortest by 1.31 to 2.37 days relative to the other seven approaches. Procedural times generally favored SuperPath, while the 2-incision approach and DAA were longer by 10-20 minutes versus the others.

In another part of the researchers’ analysis, the group created a chart using PA as the reference and comparing the other seven to it on eight different outcomes. These included hip and pain scores, hospitalization and procedural times, improvement in quality-of-life score, blood loss, cup abduction angle, and cup anteversion angle. These comparisons were also stratified by strength of evidence, for a total of 56 comparisons.

That was too many to include here, but some of the highlights were:

• MIS-DLA and MIS-PA were “definitely better” than PA for blood loss, while conventional DLA was “definitely no better”
• SuperPath was “definitely better” than PA for hospitalization time
• PA was superior to the other seven for operative time, mostly with strong evidence
• Differences in quality of life varied but were never very large

Another factor that the investigators considered was the year of study publication. In general, hospitalization times decreased with later publication, in line with overall trends seen in many countries (especially the U.S.) to discharge patients earlier.

Also, Wang and colleagues found that longer incisions decreased the procedural time but also led to smaller improvements in quality of life relative to less invasive approaches.

Taken together, the group wrote, their findings “will aid clinicians in balancing the risks and benefits of available approaches for primary [total hip arthroplasty] and provide key evidence for producing recommendations for clinical practice.”