Femoral stem migration after direct lateral and direct anterior total hip arthroplasty: a prospective cohort study

Abstract

Background: The direct lateral (DL) approach to total hip arthroplasty is more commonly used than the newer direct anterior (DA) approach. Both approaches use collared or collarless femoral stems. We sought to assess implant stability of stem designs implanted with the DL approach and compare outcomes from this cohort with those of a previously reported cohort of patients who underwent arthroplasty with a DA approach. We also sought to determine if early recovery influences differences in migration. Methods: Patients underwent total hip arthroplasty using the DL or the DA approach and were randomized to receive either a collared or collarless, cementless femoral stem. On the day of surgery and at 6 follow-up visits through to 1 year, patients underwent supine radiostereometric imaging to track implant migration. At follow-up visits, patients performed an instrumented walking test to assess their functional ability and logged an average daily step count to assess their activity levels. We assessed whether patient function and activity were correlated with migration. Results: Stem design did not have a significant effect on migration for the DL group ( p = 0.894). Compared with the DA group, the DL group migrated significantly less for both collared ( p = 0.031) and collarless ( p = 0.002) stems. Migration was not correlated with function or activity at any time point ( p > 0.05). Conclusion: Most implant migration occurred from the day of surgery to 2 weeks after the operation and stabilized thereafter, suggesting adequate fixation and a low risk for aseptic loosening in both patient groups.

Collared versus collarless hydroxyapatite-coated stems for primary cementless total hip arthroplasty; a systematic review of comparative studies. Is there any difference in survival, functional, and radiographic outcomes?

“…Four papers [ 17 , 18 , 20 , 25 ] mainly evaluated stem subsidence and RLLs, while three others [ 8 , 22 , 24 ] focused on stem performance and revision rates. One study [ 19 ], mainly assessed PPFs, survival, and complication rates, and another [ 11 ], the Corail stem stability.…”

“…Only one study did not report the overall mean age [ 22 ]. BMI was reported in 6 out of 12 studies [ 11 , 12 , 17 – 19 , 23 ]; the mean BMI of the included studies was 27.6 (kg/m 2 ) ( SD = 1.03). The follow-up ranged from 12 to 360 months.…”

“…Six studies reported extensive follow-ups up to 6 years [ 8 , 19 – 21 , 23 , 24 ]; 2 had notable >10-year follow-ups [ 20 , 23 ]. A mid-term (2–9 years) follow-up was reported in five studies [ 8 , 17 , 19 , 21 , 24 ], and a short-term (1–2 years) follow-up in four studies [ 11 , 12 , 18 , 25 ]. Table 1 shows the patients’ demographics and study characteristics.…”

“…Eight studies reported the preoperative diagnosis for primary THA [ 8 , 11 , 12 , 17 – 19 , 22 , 23 ], and then showed the surgical approach used [ 8 , 11 , 12 , 17 – 21 , 23 , 24 ]. The preoperative diagnosis was osteoarthritis in 62,336 patients (68.8%).…”

Phantom validation of a novel RSA-based impingement metric to assess component-on-component impingement risk

“…14–19 Today, it is conventionally used to investigate implant component micromotion as well as the biomechanics of novel implants. 14,20–22 In model-based RSA (MBRSA), dual x-rays are analyzed to calculate an optimal match between the virtual projection of a three-dimensional implant model (a reversed engineered or CAD model) with the contours of the implant on the dual-plane radiographs. Once matched, the three-dimensional pose of each implant component is specified, and the implant position is defined.…”