Permissive Weight Bearing in Patients With Surgically Treated Periprosthetic Femoral Fractures Around Total Hip Arthroplasty: A Scoping Review.

Periprosthetic femoral fractures (PPFF) around total hip arthroplasty (THA) are one of the leading causes of hip revision. High mortality rates are observed after revision in case of PPFF around THA. To modify risk factors, early postoperative mobilization is necessary. Permissive weight bearing (PWB) is designed to optimize clinical recovery in aftercare. This study aimed to perform a scoping review to summarize the current available evidence on postoperative weight bearing in late PPFF around THA and the implementation of PWB in aftercare. A systematic search was performed on the Cochrane Library, Web of Science, Ovid MEDLINE, EMBASE, and CINAHL databases on January 26th, 2023. Articles were screened in two stages by two independent reviewers. Studies describing adult patients with a history of primary THA who were surgically treated for late PPFF and mentioning prescribed postoperative weight-bearing protocols with relevant outcome measures were included. Seven studies were included, reporting data on 22 patients (age range 47-97 years, BMI range 19-32 kg/m2, ASA classification range 2-3). No studies used PWB in aftercare. The non-weight-bearing group showed no complications. The restricted weight-bearing group had one death and one implant failure. The full weight-bearing group experienced one deep infection and one plate removal because of impingement. The main finding was that, after an extensive systematic search, no articles could be included focusing on PWB in patients with a late PPFF after THA. Addressing this gap in the literature is essential to advancing the understanding of postoperative weight-bearing protocols and PWB for late PPFF around THA.

Survival rates of anatomically shaped and tapered slip cemented femoral implants: an analysis of 76,281 femoral implants of the Dutch arthroplasty register (LROI).

INTRODUCTION: In cemented total hip arthroplasty (THA) various shapes and geometries of femoral implants are in use. Collarless, polished, and tapered (CPT) implants, and anatomically shaped (AS) implants are most commonly used. Due to their different design features, this might lead to different survival outcomes. In this register-based study, overall implant survival and short-term complications of CPT and AS cemented implants were evaluated. METHODS: Data of the Dutch Arthroplasty Register (LROI) were used. Cemented femoral implants, which could be classified as CPT or AS were included in this study. Implants were excluded when no classification could be made or if implanted <100 times. Survival analyses were performed using Kaplan-Meier survival analysis and multivariable Cox-proportional hazard analysis. RESULTS: 76,281 cemented THAs were included. At a mean of 5.1 years follow-up (SD 3.1, range 0-12 years), the overall survival of the AS implants was higher compared with the CPT implants, with a survival, of 99.2% and 99.0% respectively (log-rank; p < 0.001). Multivariable regression analysis revealed a higher rate for revision because of loosening of the AS implants (HR 2; CI, 1.4-3.1). AS implants had a lower rate for periprosthetic fractures compared with the CPT implants (HR 0.13; CI, 0.07-0.23). CONCLUSIONS: Both designs show excellent overall survival rates at short-term follow-up. There is a higher overall survival of AS implants when compared with CPT implants. Revision for implant loosening, however, was statistically significantly higher in AS implants when compared with the CPT implants.

Disappointing long-term outcome of THA with carbon-fiber-reinforced poly-ether-ether-ketone (CFR-PEEK) as acetabular insert liner: a prospective study with a mean follow-up of 14.3 years.

INTRODUCTION: Insert liner wear of the acetabular component is one of the predictive values for survival of total hip arthroplasties (THAs). This prospective single-centre study was designed to evaluate the follow-up of carbon-fiber-reinforced poly-ether-ether-ketone (CFR-PEEK) insert liner used as bearing in cementless THAs. METHODS: 29 healthy patients with an indication for cementless THA were selected for a CFR-PEEK insert liner and followed over time. All patients received a cementless THA with a CFR-PEEK insert liner used as bearing. At different follow-up moments patients were routinely examined and were analysed using the Oxford Hip Score (OHS), the modified Merle d'Aubigne-Postel (MAP) score, and radiologically. At the follow up moments the plain radiographics where assessed for loosening, cyst formations and wear of the CFR-PEEK liners. RESULTS: At a mean of 14.3 years follow-up 4 revisions of the acetabular component were performed, resulting in a survival rate of 86.5% (CI 95%, 72.4-96.6). A statistically significant difference in OHS and MAP scores between pre- and postoperative follow-up moments was observed. The acetabular components of the remaining patients showed no radiological abnormalities at 14.3 years follow-up. The overall CFR-PEEK wear was low, with a mean of 0.81 (0.2-1.4) mm wear at 14.3 years follow-up. CONCLUSIONS: In this series we found an aseptic loosening with unclear reasons in 4 well-positioned acetabular components, hence we do not recommend routine use of CFR-PEEK insert liners as bearing in cementless THAs. All the remaining THAs and acetabular components were in situ without abnormalities at 14.3 years follow-up.

Metal ion concentrations after metal-on-metal hip arthroplasty are not correlated with habitual physical activity levels.

INTRODUCTION: Metal-on-metal (MoM) hip arthroplasties have shown high clinical failure rates with many patients at risk for a revision and under surveillance for high metal ion concentrations. Implant wear releasing such ions is assumed to be a function of use, i.e. the patient's physical activity. This study aimed to assess whether habitual physical activity levels of MoM patients are correlated with metal ion concentrations and are higher in patients with high (at risk) than in patients with low (safe) metal ion concentrations. METHODS: A cohort study was conducted of patients with any type of MoM hip prosthesis. Metal ion concentrations were determined using ICP-MS. Habitual physical activity of subjects was measured in daily living using an acceleration-based activity monitor. Outcome consisted of quantitative and qualitative activity parameters. RESULTS: In total, 62 patients were included. Mean age at surgery was 60.8 ± 9.3 years and follow-up was 6.3 ± 1.4 years. Cobalt concentrations were highly elevated overall (112.4 ± 137.9 nmol/L) and significantly more in bilateral (184.8 ± 106.5 nmol/L) than in unilateral cases (87.8 ± 139.4 nmol/L). No correlations were found between physical activity parameters and metal ion concentrations. Subgroup analysis of patients with low versus high cobalt concentration showed no significant differences in habitual physical activity. DISCUSSION: No correlation was found between physical activity levels and metal ion concentrations. Implant use by normal habitual activities of daily living seems not to influence metal ion concentrations.