Cementless revision femoral stems application of press-fit principles and clinical outcomes

Use of short stems in revision of standard femoral stem: A case report

BACKGROUND

Short stems are usually uncemented prosthetics and are recommended in the treatment of traumatic or degenerative diseases of hip. In revision procedures for elderly patients with serious comorbidity, applying a short stem could reduce peri- and post-operative secondary surgical risks to femoral osteotomy, which are necessary for the removal of parts of the implant or acrylic cement from the medullary canal. There are no cases in the literature that apply a short stem for prosthetic revision by acrylic cement anchorage.

CASE SUMMARY

A male patient had a left hip replacement in 1995 due to coxarthrosis. At the age of eighty the patient reported an accidental trauma and walked with pain in the left thigh. The X-ray highlighted the stem breakage in the distal section without fracturing the femoral cortex. The patient had various comorbidities (diabetes, anaemia, heart deficiency, and arrhythmia) presenting a high operation risk (ASA 4). During the revision procedure, the distal apex of the stem could not be removed from the femoral cortex. Because of the poor general health of the patient, the surgeon decided not to perform a Wagner femoral osteotomy to remove the distal section of the stem and decided to implant a short stem to avoid removing the stem section of the previous implant. The patient had his left femur X-rayed 15 d post-trauma.

CONCLUSION

A field of application of short stem may be the development of a cemented short stem to reduce the complexity of the revision procedure.

High Revision Rates of a Cementless Beta-Titanium Alloy Stem with Contamination-Free Roughened Surface in Primary Total Hip Arthroplasty

Optimal osseointegration of cementless total hip arthroplasty is essential for high stability and long-term survival. The purpose of this follow-up study was to evaluate the clinical and radiological outcome, the complications, and survival rates of a beta-titanium alloy stem with a specific grit-blasted-free surface. In 192 patients (mean age of 64.4 years), 202 consecutive primary total hip arthroplasties were performed using a cementless Hipstar^® stem (Stryker, Duisburg, DE). The Harris Hip Score (HHS) was assessed pre-operatively and post-operatively. Radiolucent lines were evaluated and the implant survival rate was calculated using Kaplan-Meier analysis. The mean follow-up was 7.71 years (range of 5.0–14.0 years). Overall, 15 revisions were performed. Early aseptic stem loosening was observed in six cases (2.97%). Radiolucent-lines adjacent to the stem were detected in 73 cases (83.02%), especially (70.46%) in the Gruen zones 1, 7, 8, and 14. The mean postoperative HHS was 92.65 points (range 42–100). The cumulative survival probability of the stem was 94.4% (95% CI 90.3 to 98.5%). Considering aseptic failure as an endpoint, the cumulative survival rate of the stem was 95.3% (95% CI 0.914 to 0.992) at six years of follow-up. Overall, an inferior mid-term implant survival was observed in comparison to well-established cementless stem designs.