Cemented femoral stem fixation through the anterior approach has fewer early complications than cementless fixation

Does introduction of a cemented polished taper-slip femoral stem reduce early periprosthetic fracture risk with anterior approach total hip arthroplasty? A case-matched study

BACKGROUND

Anterior approach total hip replacement (AA-THA) is associated with higher periprosthetic fracture (PFF) risk. Cemented femoral fixation may reduce this risk. This study aims to (1) determine if using a cemented polished taper-slip (PTS) stem reduces PFF risk, (2) describe perioperative complications, and (3) identify factors associated with outcome.

METHODS

This was a retrospective, case-matched cohort study from an academic center. The first 122 hybrid AA-THAs with a minimum 12-month follow-up were reviewed. These were matched (1:2) for age, sex, BMI, femoral and pelvic morphology with 244 AA-THAs using an uncemented, short, stem. Outcomes measured include PPF (Vancouver classification) rate, reoperation rate, complications, cement quality, and radiologic measurements.

RESULTS

Nineteen PFFs (5.2%) occurred at a mean 14.5±23 days following surgery. There was no difference in PPF rate between groups (Cemented Stems: 7/122, 5.7%, 5/7 Type-A and 2/7 Type-B2; Uncemented Stems: 12/244, 4.9%, 7/12 Type-A, 4/12 Type-B2 and 1/12 Type-C; p = 0.847). There was no difference in PPF risk between short (≤ 125 mm) and normal length (150 mm) stems (p = 0.676). More uncemented stems subsided (Cemented stems: 1/122, 0.8%; Uncemented stems: 27/244, 11.1%; p < 0.001). Suboptimum cementation was noted in 16 (13%) hips; two fractured and one subsided (risk-ratio [RR]: 3.9; p = 0.035). A narrow ischial width and high ilio-ischial ratio were the only morphological parameters associated with risk of PPF and subsidence.

CONCLUSION

Hybrid AA-THA did not reduce PFF risk. Suboptimal cementation was associated with increased risk of subsidence or fracture. Current instruments do not accommodate the limited working window and steeper femoral angle during AA-THA.

A comparison of cemented femoral fixation via anterior versus posterior approach total hip arthroplasty: an analysis of 60,739 total hip arthroplasties

BACKGROUND

Anterior approach total hip arthroplasty (THA) decreases the rate of dislocation but increases femoral-sided complications in the way of periprosthetic fractures and component loosening. A cemented prosthesis may reduce femoral-sided complications and improve the risk:benefit profile of anterior approach THA.

METHODS

Data from the Australian National Joint Replacement Registry were analysed for patients undergoing primary THA via the anterior or posterior approach using a cemented polished femoral stem from January 2015 to December 2021. The primary outcome measure was the cumulative percent revision (CPR) for all causes and CPR for femoral component loosening and fracture. The CPR for the primary outcome measures were compared between the anterior and posterior approach and adjusted for age, sex, ASA score, BMI and femoral head size.

RESULTS

The study included 60,739 THAs with cemented stems (10,742 anterior, 49,997 posterior). The rate of revision of the anterior versus the posterior approach did not significantly differ (HR 0.87 (95% CI, 0.74-1.03), p = 0.100). Anterior approach THA had a significantly higher rate of revision for femoral component loosening (HR 5.06 [95% CI, 3.08-8.30], p < 0.001); and a decreased rate of revision for infection (HR 0.59 [95% CI, 0.43-0.81], p = 0.001) and dislocation/instability (HR 0-3 months 0.48 [95% CI, 0.27-0.83], p = 0.008; HR >3 months 0.30 [95% CI, 0.15-0.61], p < 0.001). There was no difference in the rate of revision surgery for fracture between the 2 approaches (HR 1.01 [95% CI, 0.71-1.43]), p = 0.975).

CONCLUSIONS

There is no significant difference in overall revision rates with cemented femoral fixation performed with an anterior or posterior approach. Cemented fixation performed with the anterior approach partly mitigates femoral complications with no difference in the revision rate for fracture but an increased rate of femoral component loosening.

Cement Mantle Quality and Stem Alignment in Cemented Collarless Polished Tapered Stems Implanted via the Direct Anterior and Direct Lateral Approaches: A Single Institution Experience

BACKGROUND

The aim of this study was to compare the stem alignment and the quality of cement mantle of collarless polished tapered cemented stems inserted through the direct anterior approach (DAA) and the direct lateral approach (DLA).

METHODS

A comparative retrospective study of 232 hybrid total hip arthroplasties using a cemented collarless polished tapered stem through either the DAA (n = 147) or DLA (n = 85) was performed. Radiographic evaluation included stem alignment, cement mantle quality, and cement mantle thickness.

RESULTS

On anteroposterior radiographs, stems implanted through the DLA were more likely to be in neutral alignment, than those implanted through the DAA (83.5%[n = 71] versus 71.4% [n = 105]; P = <.001). No difference between approaches was noted for stem alignment on lateral radiographs or cement mantle quality. Multivariate analysis revealed factors associated with suboptimal cement mantle and included Dorr type B or C femur as well as male gender. A mean cement mantle thickness ≥2mm was achieved in all Gruen zones for both approaches.

CONCLUSION

In our series, the DAA was associated with a higher incidence of coronal plane stem malalignment compared to the DLA when using cemented tapered polished femoral components for total hip arthroplasty. No difference in lateral stem alignment or cement mantle quality was found.

Cemented Femoral Fixation in a High-Risk Cohort Diminishes Risk of Early Postoperative Periprosthetic Fracture

BACKGROUND

Early periprosthetic fractures (PPFx) following primary total hip arthroplasty (THA) create significant morbidity. Established risk factors for early PPFx include age, gender, body mass index, surgical approach, and implant fixation. We investigated the role of femoral fixation on early PPFx (<90 days postoperatively) in a high-risk cohort undergoing direct anterior approach (DAA) THA.

METHODS

The final cohort comprised 344 consecutive patients (390 hips) with risk factors for PPFx (age >68 years and body mass index <25 kg/m2) who underwent primary DAA THA between May 4, 2009 and December 31, 2019 and had 90-day follow-up. Noncemented fixation was used in 229-hips, while cemented fixation was used in 161 hips. The primary outcome was early PPFx. Fisher's exact test was used for categorical variables, while t-tests were used to compare continuous variables.

RESULTS

We observed 8 early PPFx (2.1%), all fractures occurring in the noncemented group. Baseline demographics were similar but not equal, with the cemented group being older (78.0 versus 76.3 years; P = .004) with a greater proportion of females (91.9% versus 69.4%; P < .001). The rate of early PPFx was significantly higher with noncemented fixation compared to cemented fixation (3.5% versus 0.0%; P = .023). A post hoc power analysis confirmed sufficient power (1-β = 0.81).

CONCLUSION

Although baseline risk factors for early PPFx are not easily modifiable, surgical factors can be modified. Cemented fixation has the potential to markedly reduce the risk of early PPFx in high-risk patients undergoing DAA THA.