Revision of double-tapered, titanium, fully hydroxyapatite-coated femoral stems: ease of extraction and subsequent reconstruction.

BACKGROUND: Fully hydroxyapatite coated, double-tapered, titanium stems are the most commonly used uncemented implants in the UK with survivorship reported at 96.3% at 23 years however there is no literature on the consequences of revision. We aimed to explore the reasons for failure, ease of stem extraction, extent of bone loss and complexity of the subsequent reconstruction. METHODS: Between December 2012 and March 2019, 104 cases requiring removal of the Corail® stem (DePuy Synthes, Warsaw, IN, USA) were identified from the National Joint Registry (NJR) and our local revision database. Indication for revision, surgical/reconstruction technique, complications and follow-up data were reviewed. RESULTS: The common reasons for revision were aseptic loosening 45.2%, infection 23.5%, instability 4.8% and peri-prosthetic fracture 12.5%. Removal of the implant without extended trochanteric osteotomy (ETO) was achieved in 94.2% of cases. Of those revised for aseptic loosening 23% were proximal, 38% were proximal/mid stem and 38% all zones. Significant bone loss is not a common feature of the failure of this stem with 95% graded as a Paprosky grade 2 or less. In terms of reconstruction, 69.2% were revised to a primary cemented stem. CONCLUSIONS: In the majority of cases revision can be achieved without an ETO and reconstruction possible using a primary stem as significant bone loss is not a common feature of failure of this stem design. We conclude that this stem is safe to use in younger patients who may outlast any type of primary implant and would inevitably face revision in their lifetime.

A comparison of mortality rates following revision hip arthroplasty for periprosthetic fracture, infection or aseptic loosening.

BACKGROUND: Mortality following revision hip surgery for periprosthetic fracture (PPF) is comparable to neck of femur fractures. Our institution provides a regional "PPF Service". The aim of this study was to determine the time to surgery and mortality rate for PPF, compared to revision for infection or aseptic loosening. METHODS: Revision arthroplasty procedures performed for PPF, infection or aseptic loosening between January 2014 and December 2015 were identified. Comparisons were made between the 3 groups for baseline demographics, admission to higher-level care, length of stay, complications and mortality. RESULTS: There were 37 PPF, 71 infected and 221 aseptic revisions. PPF had a higher proportion of females (65% vs. 39% in infection and 53% in aseptic; p = 0.031) and grade 3 and 4 ASA patients (p = 0.006). Median time to surgery for PPF was 8 days (95% CI, 6-16). Single-stage procedures were performed in 84% of PPF, 42% of infections and 99% of aseptic revisions (p < 0.001). 19% of PPF revisions required HDU admission, 1% in the aseptic group and none in the infection group. Median length of stay was significantly different (PPF 10; infection 14; aseptic 8 days (p < 0.001). The 1-year mortality rate for PPF was 0%, 2.8% for infection and 0.9% in the aseptic group (p = 0.342). CONCLUSIONS: Despite the PPF group having higher ASA grades and more HDU admissions, our 1-year mortality rate was 0% and not significantly different to infection or aseptic loosening. Our low complication and 1-year mortality rate is encouraging and supports the safety of a regional "Periprosthetic Fracture Service".

Study to Assess the Rate of Adverse Reaction to Metal Debris in Hip Resurfacing at a Minimum 13-year Follow-up.

BACKGROUND: Hip Resurfacing (HR), although reducing in popularity, is still used in the younger male population. Excellent medium-term results have been published; however, the use of metal on metal has reduced with increased awareness of adverse reactions to metal debris (ARMD). ARMD has been shown to often be clinically "silent" following large Head MoM total hip replacement (THR). The purpose of our study was to report the incidence of ARMD following HR with a minimum follow-up of 13 years. METHODS: We performed a retrospective study of a consecutive series of patients who underwent HR between January 1, 2000 and August 1, 2005. All patients were entered into our hospital MoM hip replacement surveillance program database. Patients were reviewed yearly for symptoms and blood ion levels. Patients had Magnetic Resonance (MR) imaging to assess for ARMD. RESULTS: A total of 102 patients with 123 hip replacements were included in the study. Eight hips in 7 patients were revised: two for fracture, one for avascular necrosis, and five for ARMD. A best-case scenario of 109 (93.2%) resurfacings were surviving at 13 years. With regard to the radiological analysis, 34% were found to have ARMD on MR. CONCLUSION: While the implant survivorship in our series is acceptable, we found a high incidence of ARMD. Surgeons and patients with or considering a HR should be aware of the risk of ARMD developing. This allows an informed choice as to the best implant for their personal requirement and informs of the potential modes of failure and need for long-term screening.

Venous thromboembolism incidence in upper limb orthopedic surgery: do these procedures increase venous thromboembolism risk?

BACKGROUND: In 2005, the House of Commons (HoC) Health Committee stated deaths attributed to preventable, hospital-acquired venous thromboembolism (VTE) numbered upwards of 25,000 per annum. Nationwide prevention of VTE became the topic of a major health campaign. The HoC Health Committee stated there was an unstratified VTE risk of between 45% and 51% associated with orthopedic surgery. VTE research in orthopedic surgery has been concentrated on lower limb procedures. Experience suggests that this kind of relation does not hold true for upper limb orthopedic procedures. This project aimed to estimate the incidence of postoperative VTE in upper limb orthopedic surgery. METHODS: The incidence of postoperative VTE was assessed in 3357 consecutive upper limb orthopedic operations performed by 4 surgeons in Lancashire Teaching Hospitals National Health Service (NHS) Trust (LTHTR) between July 1, 2009, and July 31, 2012. RESULTS: Four pulmonary embolisms and 2 deep vein thromboses occurred. Incidence of postoperative VTE was 0.0018%, significantly lower than rates reported in the literature. Five of 6 patients who developed a VTE reported a personal or family history of VTE. Three patients would not have been identified as at risk under the current VTE screening guidelines. Three of these patients received appropriate anticoagulation according to present guidelines, yet VTE events still occurred. CONCLUSION: These results indicate VTE risk in orthopedic upper limb surgery is much lower than reported in the literature. The necessity for screening for VTE in upper limb surgery is contested. The efficacy of VTE screening and current VTE prophylaxis is discussed, and an alternative and much simplified method of screening is suggested.

Effects of estradiol and FSH on maturation of the testis in the hypogonadal (hpg) mouse.

BACKGROUND: The hypogonadal (hpg) mouse is widely used as an animal model with which to investigate the endocrine regulation of spermatogenesis. Chronic treatment of these GnRH-deficient mice with estradiol is known to induce testicular maturation and restore qualitatively normal spermatogenesis. The aim of the current studies was to investigate whether these effects of estradiol are direct effects in the testis, or indirect actions via paradoxical stimulation of FSH secretion from the pituitary gland. METHODS: Initially, Western blot and immunohistochemistry were used to analyse tissues from hpg mice to identify potential sites of action of estradiol. In the main study, hpg mice were treated for 50 days with either an estradiol implant or daily injections of recombinant human FSH, or a combination of both, to determine whether estradiol would have an additive or synergistic effect with FSH on testis development, as assessed by histological analysis and stereological quantification of Leydig, Sertoli and germ cell proliferation. RESULTS: Western blot analysis revealed ERalpha immunoreactive bands of appropriate molecular weight in extracts of testis and pituitary glands from hpg mice, and immunohistochemical studies confirmed ERalpha in nuclei of anterior pituitary cells and Leydig and peritubular cells in hpg mice. Histological and morphometric analyses revealed that estradiol treatment alone was as effective as FSH in promoting Sertoli cell production and proliferation of the seminiferous epithelium, resulting in the production of elongating spermatids. Combined estradiol and FSH treatment did not produce a greater effect than either treatment alone, though an increased dose of FSH significantly increased seminiferous tubule volume and testis weight and increase Sertoli cell numbers further within the same time frame. In contrast, estradiol caused substantial increases in the wet weight of the seminal vesicles, whereas FSH was without effect on this tissue, and did not augment the actions of estradiol. CONCLUSION: As ERalpha receptor is abundantly expressed in the pituitary gland of hpg mice, and estradiol did not exert effects on testis development over and above those of FSH, we conclude that the action of estradiol on testis development in hpg mice is predominantly via the stimulation of pituitary FSH release.