Large head metal-on-metal bearing surface with a TMZF titanium alloy femoral stem with high rates of revision and trunnion failure.

Background: Mechanically assisted crevice corrosion at the head-neck interface puts implants at risk of trunnionosis, femoral head dissociation, implant failure and the development of metallosis. Metal-on-Metal bearings have very low wear rates, significantly lower than metal-on-polytethylene, but their wear results in cobalt and chromium ion systemic distribution. This is a study of the MITCH metal-on-metal bearing surface coupled with an Accolade TMZF stem. Methods: This was a retrospective review of 24 total hip replacements 21 patients in that underwent MITCH TRH/Accolade TMZF implantation at a minimum of 12 years post operatively. The primary outcome of this study was all-cause revision with particular attention to revision due to trunnion failure and/or cobalt and chromium ion level. Results: There was a revision rate of 66.7 % (n = 16) at a minimum of twelve years post operatively. Most notably there were six revisions for a gross trunnion failure. Two cases were revised for impending trunnion failure. There were seven cases revised for elevated serum cobalt and chromium levels and one was revised for unexplained pain. Discussion: Patients in our study that underwent TMZF alloy cementless stems coupled with large cobalt chromium alloy heads are at high risk of catastrophic trunnion failure. The high rate of trunnnionosis in this implant combination is thought to be related to a significantly different Young's modulus due to a material mismatch coupled with galvanic corrosion.

Open Reduction and Internal Fixation and Cement-In-Cement Revision for Selected Vancouver B Proximal Femur Periprosthetic Fractures.

The incidence of periprosthetic proximal femoral fractures is increasing with the increase in arthroplasty being performed as well as aging populations. We describe an open reduction and internal fixation and cement-in-cement technique utilizing a well-fixed cement mantle. The advantages of this allow for a shorter operative time, reduction in risk of iatrogenic femoral fractures, and reduction in blood loss. This was a retrospective study reviewing 20 patients that underwent this technique for periprosthetic fractures. Thirty percent (n = 6) of patients underwent subsequent surgery. We had a 95% (n = 19) union rate with 1 case refracturing through the old fracture. This technique can allow for shorter operative times and a lower physiological insult in reducible periprosthetic proximal femur fractures with a stable cement mantle.

The 50 most influential papers pertaining to the Ilizarov method: A bibliometric analysis.

The Ilizarov method has become a widely recognised surgical technique. A bibliometric analysis of the 50 most-cited publications relating to the Ilizarov method was carried out. Cumulative number of citations was 4,918. Mean number of citations was 98. h-index was 50. Impact factor of these journals ranged from 0.5-5.082. Our study suggests that a highly cited and influential paper likely originated from an American journal with a high impact factor and was published in the 1990s/2000s. Our compilation of the 50 most influential papers on the Ilizarov method will prove invaluable to those in training and those involved in further advancing the technique.

Readability and quality of online information for patients pertaining to revision knee arthroplasty: An objective analysis.

BACKGROUND: Modern patients use the internet more frequently for their health information. Our aim was to assess the quality and readability of online patient education materials relating to revision knee arthroplasty. We hypothesised that this information would be too difficult to read for the average patient and of a lesser quality than desired. METHOD: A search of the top 50 results on 3 search engines (Google, Bing, Yahoo) was completed (MeSH "revision knee arthroplasty", "revision knee replacement"). Readability of these websites was calculated using a specialised website, www.readable.com to produce 3 scores (Gunning-Fog (GF), Flesch Reading Ease (FRE), Flesch-Kincaid Grade (FKG). Quality was assessed using the Journal of American Medical Association (JAMA) benchmark criteria and the Health On the Net (HON) code toolbar extension. RESULTS: 89 unique websites were identified. Mean FRE was 44.01 ± 11.05. The mean GF was 12.01 ± 2.94. The mean FKG level was 10.06 ± 1.95. As per the FRE score, no webpage was pitched at or below a sixth grade reading level. The GF index identified only 3 websites (3.4%) at 6th grade reading level. As per FKG score, most webpages (n = 58, 65.2%) found themselves in the 10th grade reading level and above. Four websites (4.5%) displayed a HONcode certificate. However, all had expired. Most websites (n = 34, 38.2%) didn't meet any of the JAMA criteria. CONCLUSION: The reading level of these materials is too high for the average patient and of a low quality. Given what we know about levels of health literacy and their relationship with patient outcomes, it is vital that we address these deficiencies promptly.

Lessons from lockdown: Virtual Clinics and service reorganisation in fracture management during COVID 19 experience of an Irish Regional Trauma Unit.

BACKGROUND: Trauma places a burden on healthcare services accounting for a large proportion of Emergency Department presentations. COVID-19 spread rapidly affecting over 30 million worldwide. To manage trauma presentations the Department of Trauma & Orthopaedic Surgery reorganised service delivery. AIM: To assess the impact of service reorganisation and Virtual Clinics on patients in a Regional Unit in Ireland. METHODS: A retrospective review of trauma activity following introduction of Virtual Fracture Clinics and Theatre COVID Pathways for a 10 week period in comparison with the same 2019 period. All patients underwent both nasopharyngeal and oropharyngeal swabs PCR testing prior to operations. Theatre and outpatient activity were evaluated. Clinic data were accumulated using the Integrated Patient Management System. RESULTS: Theatre Activity: 242 patients underwent surgery in our trauma unit (mean 2.98 per list) during the COVID- 19 period. 29 cases were performed in repurposed elective hospital giving a total of 271 during the 2020 study period. 371 cases were performed in the same 2019 period (mean 4.58 per list). Outpatient Activity: We noted a 25.86% fracture clinic referral reduction during the COVID 19 period compared to 2019. There was a 150.77% increase in patients managed through Trauma Assessment Clinic. 639 patients were managed through the Virtual Fracture Clinic Pathway during COVID 19 period. CONCLUSIONS: Over one in four fracture clinic patients can be managed virtually. A new dedicated Acute Fracture Unit within our institution permitted streamlining of care and social distancing. The "Non-COVID" pathway for ambulatory trauma was essential in managing the growing presentations of these injuries.

Cause of irreducible dislocation of a re-revision THR.

Instability or recurrent dislocations are a common reason for revision of total hip replacements (THRs). Dual-mobility constructs can help improve stability by increasing the femoral head jump distance. These constructs are used to decrease the risk of re-revision in the setting of recurrent dislocation. This case describes an unusual case of irreducible dislocation of a re-revision THR due to intraprosthetic dislocation. The patient required open reduction and revision of this construct to a tripolar implant. This is important to appreciate from an emergency medicine point of view as repeated attempts at reduction will be fruitless and may result in a femur fracture. This particular type of dislocation is very rare. Perioperative considerations should include early referral to the orthopaedic team for reduction in theatre, and having a low threshold for open reduction. Revision options should be available when bringing a case like this to the operating theatre.

The effect of time to surgery on functional ability at six weeks in a hip fracture population in Mid-West Ireland.

Patients with a hip fracture may be appropriately delayed for surgery as they require optimisation or clinical interventions to treat acute medical illnesses (Moja et al., 2012). Other patients are inappropriately delayed due to hospital factors (Brener, 2013; Lee & Elfar, 2014). Timely efficient admission and surgery is well documented as the best course of management for these patients. The aim of this prospective cohort longitudinal follow-up study was to establish if a relationship existed between duration of time spent in the Emergency Department (ED), time to surgery and functional ability in patients with hip fractures and to examine the effect prolonged waits may have on ability to return home. Functional ability for fifty one patients with a hip fracture was evaluated using the Barthel Index Score (BIS) on admission and at six weeks post-surgery. Data were analysed by using SPSS version 20. The findings reveal a change in BIS at 6 weeks for patients whose surgery is delayed. Patients who experienced long delays awaiting admission (>12 h) in the ED functioned less well (Kruskal-Wallis test p = 0.033). Correlation existed between time to surgery and returning to pre-fracture place of residence, (p = 0.000 Pearson chi-square), which also remained significant while controlling for age. Prolonged waits had an overall negative impact on patients' post-fracture functional ability. This study highlights the deleterious effects on functional ability when surgery is delayed.

A comparison of acetabular impaction grafting and trabecular metal for revision arthroplasty.

BACKGROUND: Acetabular defect reconstruction in revision hip arthroplasty may be achieved with acetabular impaction bone grafting (AIBG) or porous trabecular metal (TM) implantation. We sought to compare clinical and radiological outcomes of both methods at a single institution. METHODS: 36 patients that were revised using AIBG and 17 patients that were revised with TM were retrospectively reviewed from local joint registry data. 82% of the TM group and 64% of the AIBG group were ≥ Paprosky 2c. Rerevision was considered failure. Radiographs demonstrating 5 mm of migration of femoral head and 5° of acetabular component inclination change were considered loose. RESULTS: Age at surgery was earlier in the AIBG group (median 68 years vs. 74 years). Median follow-up was 5.9 years for AIBG and 5.4 years for TM. Harris Hip Scores improved significantly for both groups (mean improvement: 32 vs. 31). There were 4 failures (11%) in the AIBG group and none in the TM group. 3 of the 4 AIBG failures occurred following second-stage revision for prosthetic joint infection. 4 (11%) and 2 (12%) hip reconstructions demonstrated radiological evidence of loosening in AIBG and TM groups respectively. CONCLUSIONS: AIBG and TM acetabular defect reconstructions achieve good clinical outcome but there is greater success with TM in higher grades of acetabular deficiency regardless of prior infection.

In vitro comparative assessment of the mechanical properties of PMMA cement and a GPC cement for vertebroplasty.

AIMS: To develop a Glass Polyalkenoate Cement that is suitable for vertebroplasty. METHODS: Testing was carried out to assess the effect of gamma irradiation used for sterilisation, on the glass transition temperature as well as its mechanical properties, including compressive strength and biflexural strength in vivo as well as testing GPC and PMMA cements post injection in cadaveric human vertebral bone. RESULTS: There was a trend to a higher failure load required for the GPC cement group compared to the current standard PMMA injected group but this was not statistically significant with this small sample size. CONCLUSION: The results are encouraging for future research to continue on GPC cements for use in vertebroplasty.

Review of quality of x-rays for templating for total hip arthroplasty.

Digital templating of x-rays for total hip arthroplasty is used routinely for pre-operative planning. This is to assure that appropriately sized implants are selected to replicate patient's hip biomechanics. Multiple studies have shown that templating does not always correspond to the final implants used. The aim of this study was to assess the suitability of the x-rays taken pre-operatively for templating for total hip arthroplasty. We undertook a review of a series of pre-operative templating pelvis x-rays in 100 consecutive patients undergoing total hip arthroplasty. These x-rays were compared against set criteria to determine their suitability for use for templating. We determined that six x-rays met the criteria whereas ninety four x-rays did not meet the criteria for suitable x-rays. Twenty patients had repeat x-rays. The reasons for unsuitability were inadequate opposite femur (66%), absence or incomplete template (54%), inadequate femur length (47%), external rotation (39%), absence of opposite hip (4%). The twenty repeated x-rays were also reviewed for the same parameters and two (10%) satisfied the established criteria. It is imperative that x-rays for templating for total hip arthroplasty are done to a strict standard to obtain an x-ray that is appropriate for templating and there is minimal exposure of the patient to irradiation.

Haemodynamic performance of neuromuscular electrical stimulation (NMES) during recovery from total hip arthroplasty.

BACKGROUND: Patients post total hip arthroplasty (THA) remain at high risk of developing Deep Vein Thrombosis (DVT) during the recovery period following surgery despite the availability of effective pharmacological and mechanical prophylactic methods. The use of calf muscle neuromuscular electrical stimulation (NMES) during the hospitalised recovery period on this patient group may be effective at preventing DVT. However, the haemodynamic effectiveness and comfort characteristics of NMES in post-THA patients immediately following surgery have yet to be established. METHODS: The popliteal veins of 11 patients, who had undergone unilateral total hip replacement surgery on the day previous to the study, were measured using Doppler ultrasound during a 4 hour neuromuscular electrical stimulation (NMES) session of the calf muscles. The effect of calf muscle NMES on peak venous velocity, mean venous velocity and volume flow were compared to resting values. Comfort was assessed using a 100mm non-hatched visual analogue scale taken before application of NMES, once NMES was initiated and before NMES was withdrawn. RESULTS: In the operated limb NMES produced increases in peak venous velocity of 99% compared to resting. Mean velocity increased by 178% compared to resting and volume flow increased by 159% compared to resting. In the un-operated limb, peak venous velocity increased by 288%, mean velocity increased by 354% and volume flow increased by 614% compared to basal flow (p<0.05 in all cases). There were no significant differences observed between the VAS scores taken before the application of NMES, once NMES was initiated and before NMES was withdrawn (p=.211). CONCLUSIONS: NMES produces a beneficial hemodynamic response in patients in the early post-operative period following orthopaedic surgery. This patient group found extended periods of calf-muscle NMES tolerable. TRIAL REGISTRATION: ClinicalTrials.gov NCT01785251.

The first intermetatarsal angle in hallux valgus: an analysis of measurement reliability and the error involved.

In view of the importance placed on the first intermetatarsal angle in the assessment of surgical intervention in hallux valgus, we assessed the reliability with which one measures this angle. The study involved 10 observers of varying experience measuring the angle using a standard technique on 10 weightbearing AP X-rays of the foot on three separate occasions. The margin of error in measuring the angle was +/-3.60 degrees with a 95% confidence interval. Increasing and averaging the number of readings per observer or the readings of a number of observers, reduces the error. Experience doesn't improve reliability. In conclusion, improvement in the reliability of the measurements can be achieved by careful technique, performing the measurements at least twice, and averaging them.

Atypical ganglion cell tumor of the sciatic nerve.

CONTEXT: Although herniation of a lumbosacral intervertebral disk is a major cause of sciatic distribution pain, relentlessly progressive symptoms or signs should alert one to the possibility of a tumor involving the nerve. OBJECTIVE: To describe the clinical, neurophysiological, and histological features of a pathologically unique tumor involving the sciatic nerve. SETTING: Tertiary referral university hospital. PATIENT: A 36-year-old woman was seen with a 6-year history of increasingly severe symptoms in the distribution of the left sciatic nerve. RESULTS: Electromyography indicated a sciatic nerve lesion in the region of the greater sciatic notch. Magnetic resonance imaging demonstrated a tumor involving the left sciatic nerve in this area. Light microscopy, electron microscopy, and immunohistochemistry results confirmed the presence of an atypical ganglion cell tumor of the sciatic nerve that exhibited prognostically conflicting clinical and histological features. CONCLUSIONS: To our knowledge, this is the first report of an atypical ganglion cell tumor affecting the sciatic nerve, and illustrates the value of detailed neurophysiological examination in localizing the site of peripheral nerve injury to facilitate focused neuroimaging when standard investigations are uninformative. Longer follow-up is required to determine the true biologic potential of this lesion.