A prospective randomized study comparing electrochemically deposited hydroxyapatite and plasma-sprayed hydroxyapatite...

Uncemented femoral stems require reliable coatings to promote osseointegration. Plasma-sprayed hydroxyapatite (HA) is widely used but may have limitations in long-term bone remodeling. Researchers have proposed alternative coatings that could improve transport of bone-active substances. Prior studies have shown HA coatings support initial fixation but may not optimize long-term bone retention. No prior work had resolved whether electrochemical deposition could match plasma spraying in clinical outcomes. This gap motivated investigation into a new coating method called Bonemaster (BM). The need for alternative coatings arises from potential benefits in bone transport and remodeling. Researchers aim to compare BM with HA to determine if it offers equivalent or superior performance.

The study aimed to evaluate whether electrochemically deposited hydroxyapatite (BM) could serve as a safe alternative to plasma-sprayed hydroxyapatite (HA) in uncemented femoral stems. Researchers focused on comparing clinical and radiological outcomes between the two coatings. The primary goal was to assess if BM would not be inferior to HA in fixation and bone remodeling. The study also aimed to measure subsidence and micromotion after implantation. Researchers wanted to determine if BM could retain bone as effectively as HA. The hypothesis was that BM would perform similarly to HA in clinical results. The study sought to provide evidence for alternative coating methods in hip arthroplasty. The findings could influence future implant design and coating selection.

The study involved 55 hips in 50 patients who received uncemented femoral stems. Stems were tapered and porous-coated proximally. One group received plasma-sprayed hydroxyapatite (HA), while the other received electrochemically deposited hydroxyapatite (BM). Patients were monitored postoperatively and at 3, 6, 12, and 24 months. Fixation was measured using radiostereometric analysis (RSA). Bone mineral density was assessed with dual-energy X-ray absorptiometry (DXA). Conventional radiography was also performed. Clinical outcomes were evaluated using Harris hip score and Oxford hip score. The study compared migration, rotation, and subsidence between the groups. Researchers analyzed data to determine if BM was non-inferior to HA.

After 24 months, both HA and BM groups showed minimal subsidence (0.25 mm and 0.28 mm, respectively). No statistically significant differences were found in migration or rotation between the groups. The BM group retained significantly more bone in Gruen zone 1 compared to HA. Bone mineral density measurements showed no major differences between the two coatings. Clinical scores, including Harris and Oxford hip scores, were similar in both groups. Radiostereometric analysis confirmed comparable fixation stability in both groups. The study found no evidence of inferiority for BM compared to HA. Results suggest BM could be a viable alternative coating method.

The authors concluded that electrochemically deposited hydroxyapatite (BM) does not appear to be inferior to plasma-sprayed hydroxyapatite (HA) in clinical and radiological outcomes. The study found no significant differences in subsidence, migration, or rotation between the groups. BM retained more bone in Gruen zone 1 compared to HA, suggesting potential advantages in bone remodeling. Clinical scores were comparable in both groups, indicating similar functional outcomes. The authors propose that BM could serve as a safe alternative coating. The findings support further investigation into BM’s long-term performance. The study does not suggest BM is superior but confirms it is non-inferior to HA. The results align with the hypothesis that BM could match conventional coatings in hip arthroplasty.