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INTRODUCTION: Fracture of the femoral stem is the cause of ~1 % of revisions after total hip arthroplasty. The risk increases intrinsically with modularity, whereby modularity is particularly useful in revision arthroplasty. We present 7 cases of failure of a specific modular, tapered, fluted, titanium alloy Revitan stem and analyse the different failure modes. METHODS: Retrospective review of all Revitan stems revised at our institutions due to implant failure and analysis of clinical presentation, diagnostic workup, and failure mode. The retrieved components were analyzed by optical and scanning electron microscopy. RESULTS: A total of 7 cases were included. There was a significant time lag between symptom onset and correct diagnosis. Conventional radiographs and low-dose CT scans (CT scout imaging) were decisive for diagnosis. All failures occurred at the level of the connection between the proximal component and the distal part of the stem. Three different failure modes were identified: loosening of the proximal component, fatigue fracture of the connection pin, and distal loosening of the connection pin. No alterations of the microstructure or deviation from manufacturing specifications regarding dimensions were observed. Failure was caused by mechanical overload. CONCLUSION: Conventional radiographs are the mainstay in identifying failed modular stems. Repeated radiographs and low-dose CT scans may be helpful additions. No single modification of the connection will address all possible failure modes. Modularity of revision stems offers advantages up until insertion of the definitive stem. Monoblock definitive stems might overcome the potential mechanical weaknesses of modularity and should be considered in relatively young, heavy and active patients.

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Osteonecrosis of the femoral head is a disease that leads to gradual degeneration of the hip joint causing immobility and a devastating impairment of quality of life. Early stage disease is characterised by a bone marrow edema of the proximal femur, a sight it shares with bone marrow edema syndrome. Although total hip arthroplasty offers quick symptom relief and functionally appealing results the treatment remains challenging, with its particularly young patients and considering limited non-invasive treatment options. We treated 6 patients with bone marrow edema in MRI and suspected osteonecrosis of the hip joint with calcium dobesilate, a vasoactive agent used in the treatment of diabetic retinopathy. We could demonstrate rapid symptom relief and concomitant disease remission on control MRI in early stage disease without any adverse events. Patients at advanced stages benefited in terms of pain reduction, but the treatment failed to halt disease progression. To the best of our knowledge, this is the first report of the therapeutic administration of calcium dobesilate in patients with bone marrow edema syndrome or osteonecrosis of the hip joint.

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INTRODUCTION: Goal of the study was an analysis of functional outcomes after radical prostatectomy (RP) in a large cohort of patients. METHODS: Functional outcomes were assessed with the ICIQ-SF questionnaire and daily pad-usage for the evaluation of stress urinary incontinence (SUI) as well as with the IIEF-5 score for the evaluation of erectile dysfunction (ED). Statistical analysis included log-rank test, Mann-Whitney-Test, ANOVA test and logistic regression (P < 0.05). RESULTS: In total 4003 patients were included in the study. Median follow-up was 42 months (min. 2-max. 147 mo.). Regarding ED, an IIEF-5 score of ≥20 was reached by 39% of patients. Regarding SUI, 55% stated that they needed no pads, 21% of patients needed one pad per day. 33% of patients reported of no incontinence (0 p. in ICIQ), 26% of patients reported of a mild incontinence (1-5 p. in ICIQ). Patients global impression of their overall health respectively patients subjective quality of life were assessed with the EORTC QLC-C30 and were both high with a median of six points (on a scale of 1-7). In multivariate analysis time since surgery could be identified as independent risk factors on QOL (P = 0.0028), IIEF-5 (P = 0.0149), ICIQ (P < 0.001), and pads per day (P < 0.001). CONCLUSIONS: Our data show a good continence status, a clearly impaired erectile function but overall a good quality of life after surgery. In summary older patients-with an advanced tumor and adjuvant radiation therapy-were at highest risk for an impaired functional outcome.

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