BACKGROUND:The purpose of this research is to highlight a new issue facing national joint registries called 'Implant Camouflage', whereby a poorly performing implant combination within an overall brand portfolio is hidden by other high performing implant combinations. METHODS:This was an international multi-centre case-control study assessing implant combinations within the NexGen® TKA portfolio. There were 9392 primary TKA components included with 1744 'high-risk' cases and 7648 'standard-risk' controls. The median time to follow-up was 7.4 (IQR 4.8-9.4) years in the cases and 10.4 (IQR 7.5-13.8) years in the control group. The primary outcome variable was revision for aseptic loosening. All-cause revision was a secondary outcome variable. Cox regression and Kaplan-Meier (KM) survival analysis was used to determine survivorship free of revision for aseptic loosening. RESULTS:The high-risk cases had significantly higher rates of revision for aseptic loosening (5.2 % v 0.4 %, p < 0.001) and all-cause revision (7.9 % v 2.9 %, p < 0.001). KM curves demonstrated higher rates of aseptic loosening in the high-risk cases with no intersection of 95 % confidence intervals with the controls. On univariate analysis, older age (p < 0.001) and higher BMI (p < 0.001) patients had significantly higher rates of revision for aseptic loosening. After multivariate analysis, the high-risk component cases were the most significant predictor of early failure for aseptic tibial loosening (p < 0.001). CONCLUSIONS:The NexGen® Option-LPS Flex and Option-LPS GSF combinations have over a 10-fold higher revision rate for aseptic loosening when compared to other implant combinations in the NexGen® portfolio.

Introduction: Revision hip arthroplasty in the presence of complex acetabular deficiencies is challenging. Cement, allograft, reconstruction rings and porous trabecular metal now provide versatile options for acetabular fixation and restoration of acetabular offset. We compare acetabular impaction bone grafting (AIBG) and trabecular metal (TM) cups at long-term follow-up. Methods: 53 patients who underwent revision hip arthroplasty were retrospectively reviewed from local joint registry data. 36 patients were revised using AIBG and 17 with TM. Median clinical follow-up was 9.57 (2.46–18.72) years and 9.65 (7.22–12.46) years, respectively. 82% of the TM group and 63% of the AIBG group were ⩾ Paprosky 2C. Re-revision was considered failure. Radiographs demonstrating 5 mm of femoral head migration and 5° of acetabular component inclination change were considered loose. Results: Patients receiving AIBG were younger (68 vs. 74 years) with a longer interval from initial arthroplasty to revision (17 vs. 13 years). Revisions in both groups were indicated most commonly for failed cementing (AIBG 88.9% vs. TM 70.5%). No TM reconstructions underwent re-revision, with only 1 failing at 6.3 years, compared with 9 AIBG re-revisions. When revising for sepsis, 33% of AIBG revisions failed. Conclusions: AIBG demonstrated high failure rates at long-term follow-up when compared to TM constructs. We recommend the use of AIBG in small cavitary defects only. We strongly advise against its use in the setting of significant bony defects and for prosthetic joint infection.

Aims Total knee arthroplasty (TKA) is a common and safe orthopaedic procedure. Zimmer Biomet's NexGen is the second most popular brand of implant used in the UK. The primary cause of revision after the first year is aseptic loosening. We present our experience of using this implant, with significant concerns around its performance with regards early aseptic loosening of the tibial component. Methods A retrospective, single-surgeon review was carried out of all of the NexGen Legacy Posterior Stabilized (LPS) TKAs performed in this institute. The specific model used for the index procedures was the NexGen Complete Knee System (Legacy Knee-Posterior Stabilized LPS-Flex Articular Surface, LPS-Flex Femoral Component Option, and Stemmed Nonaugmentable Tibial Component Option). Results Between 2013 and 2016, 352 NexGen TKAs were carried out on 331 patients. A total of 62 TKAs have been revised to date, giving an all-cause revision rate of 17.6% at a minimum of five years. Three of these revisions were due to infection. Overall, 59 of the revisions were performed for aseptic loosening (16.7%) of the tibial component. The tibial component was removed intraoperatively without instrumentation due to significant tibial debonding between the implant-cement interface. Conclusion While overall, we believe that early aseptic loosening is multi-factorial in nature, the significantly high aseptic revision rate, as seen by an experienced fellowship-trained arthroplasty surgeon, has led us to believe that there is a fundamental issue with this NexGen implant design. Continued implant surveillance and rigorous review across all regions using this particular implant is warranted based on the concerning findings described here. Cite this article: Bone Jt Open 2022;3(6):495–501.

Background: Total knee arthroplasty (TKA) is a common orthopedic procedure with 975,739 performed in the UK between 2003 and 2016. The two most common prosthetics used are P. F.C. Sigma and NexGen. The aim of this study is to compare the experience of a single fellowship-trained arthroplasty surgeon at a single dedicated orthopedic hospital using both of these prosthetics over a 17-year period. Methods: This study was carried out as a retrospective review. Information was gathered from a database of primary TKAs and revision TKAs, as well as medical records, correspondence and operative notes. Results: A total of 1,511 TKAs were performed between 1999 and 2015 - with a further followup period of 2 years. There were 1,161 consecutive P.F.C. primary TKAs done from 1999 to April 2013, after which, 350 consecutive NexGen primary TKAs were performed. Between 2015 and 2017, 26 NexGen revisions were required. 23 (6.6%) of the NexGen knees were carried out for aseptic loosening. The average time for revision from the NexGen index surgery was 30.4 months. The failures all presented similarly - with the tibial component having collapsed into varus and radiographic lucency noted under the implant. Conclusion: In spite of changes in orthopedic practice and advances in implant technology over the time period of this study, we would not expect this level of implant failure from a surgeon who had no previous significant issues with aseptic loosening using a different prosthetic. Usage of the NexGen knee has been discontinued at this center. (C) 2019 Elsevier B.V. All rights reserved.

Total knee arthroplasty (TKA) is a common orthopaedic procedure with over 1,500 done in 2016 in Ireland alone. 96% of all TKAs are due to pain in the knee associated with osteoarthritis. According ...

Background: The role of Orthopaedic Advanced Nurse Practioner (OANP) is novel within the Irish healthcare system, despite its proven benefit internationally, with huge potential to enhance fracture clinic activity, reduce Non-Consultant Hospital Doctors (NCHD) workload and enhance the overall fracture clinic experience for patients. The aim of this study was to assess the role of our OANP, in the management of fracture clinic patients through an intra-departmental comparison with NCHDs.

A 69-year-old female with a history of bilateral total hip replacements presented with rigors, fever and sudden onset left groin pain. A pelvic X-ray showed well-fixed implants. Blood results revealed a leucocytosis (white cell count 22.3 × 109 l-1) and elevated C-reactive protein (211 mg/l). Ultrasound-guided aspiration of her left hip grew Streptococcus gordonii No source infection could be identified apart from a new chronic sinus infection in a left upper incisor. Following a discussion with the patient a 6-week course of intravenous ceftriaxone was started and was successful in normalizing her inflammatory markers. She was placed on long-term suppressive amoxicillin following this. Her suppressive antibiotic therapy was complicated by the development of a clostridium difficile infection and her antibiotics were changed to doxycycline. At 1-year follow-up, she was asymptomatic with no further episodes of groin pain or fever.

Synchronous quadriceps tendon rupture is rare. A 29-year-old man, an amateur weight lifter, taking androgenic-anabolic steroids (AAS), developed sudden onset bilateral pain and swelling of his anterior thighs when attempting to squat 280 kg (620 lb). Examination revealed gross swelling superior to the patella and palpable gaps in both quadriceps tendons. He underwent successful operative repair. MRI revealed a partial tear of the anterior cruciate ligament (ACL) of the right knee. This was not reconstructed. Only a few case reports of the association between AAS and quadriceps rupture exist in the literature, with none to the best of our knowledge in the past 10 years. ACL rupture coexisting is very rare, with only two reported cases.

BACKGROUND:Performing successful total hip replacement (THR) in dysplastic, subluxed, and dislocated hip is a challenging task. Here, we assessed midterm clinical and radiological outcomes of uncemented total hip arthroplasty in osteoarthritis (OA) of hip secondary to Hartofilakidis low and high-dislocated hips with a mean follow-up of 8.8 years.MATERIALS AND METHODS:A retrospective study of prospectively collected data was designed involving all consecutive patients who underwent uncemented THR for OA of hip secondary to developmental dysplasia of the hip and Grade II or Grade III Hartofilakidis classification.RESULTS:Thirty-two patients underwent 45 THR, with 23 Grade II (low dislocation) and 22 Grade III (high-dislocation) of Hartofilakidis classification. Thirteen patients had bilateral hip replacements, 19 patients had unilateral THR. There was highly statistically significant difference between preoperative and postoperative HHS and SF-36v2™ at each follow-up. Survivorship of original implant was 98.88% at a mean follow-up of 8.8 years. The mean improvement in leg length in this series was 3.6 cm (1.8-4.5, 95% confidence interval). No sciatic nerve or femoral nerve palsies were observed.CONCLUSIONS:Uncemented THR provides better function and quality of life. However, longer follow-up studies are needed to assess survivorship of uncemented THR in Hartofilakidis low and high-dislocations.

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.

Case: We describe the case of a forty-one-year-old man who underwent total hip arthroplasty with a 32-mm BIOLOX delta ceramic head articulating with a polyethylene liner. The patient did not suffer any trauma postoperatively, and his only symptom was of a “clicking” noise from the operatively treated hip. At his six-week postoperative review, fracture of the femoral head was diagnosed. Conclusion: Fracture of a ceramic femoral head is a rare but catastrophic complication. This case report highlights the importance of vigilance on the part of the surgeon when reviewing patients after hip arthroplasty with ceramic-on-polyethylene bearing couples, even with limited symptoms associated with the hip and no reported trauma.

Objectives: Hip arthroplasty registries, encompassing all-cause end-stage hip degeneration, have shown that slightly more right hip replacements are performed than left. Given that greater than 85% of individuals are right-handed, we sought to investigate the association between side of hand dominance and side of hip osteoarthritis.Methods: This Level III observational study evaluated exclusively end-stage osteoarthritis of the hip, using 3 independent centres totalling 386 consecutive arthroplasty patients. Logistic regression was used as a statistical model.Results: In total, 322 patients with hip osteoarthritis were included in the final analysis, including 146 (45.5%) women and 176 (54.5%) men, with a mean age of 68.1 years (SD = 9.5 years). There were 133 (41.2%) right, 73 (22.6%) left, and 116 (35.9%) bilateral hips where the contralateral side had been previously replaced. The proportion of individuals requiring unilateral hip arthroplasty on their dominant side was 67.4%.Conclusions: In the development of hip osteoarthritis, one is significantly more likely to require hip arthroplasty on their dominant side than in the contralateral hip. Assessment of hand dominance identifies cerebral laterality as a contributing factor in predisposing one's dominant side to hip osteoarthritis. (C) 2014 Elsevier Inc. All rights reserved.

Prosthetic joints and other orthopedic implants have improved quality of life for patients world-wide and the use of such devices is increasing. However, while infection rates subsequent to associated surgery are relatively low (<3%), the consequences of incidence are considerable, encompassing morbidity (including amputation) and mortality in addition to significant social and economic costs. Emphasis, therefore, has been placed on mitigating microbial risk, with clinical microbiologists and surgeons utilizing rapidly evolving molecular laboratory techniques in detection and diagnosis of infection, which still occurs despite sophisticated patient management. Multidisciplinary approaches are regularly adopted to achieve this. In this commentary, we describe an unusual case of Actinomyces infection in total hip arthroplasty and, in that context, describe the perspectives of the clinical microbiology and surgical teams and how they contrasted. More specifically, this case demonstrates an ad hoc approach to structured eradication of biofilms and intracellular bacteria related to biomaterials, as reflected in early usage of linezolid. This is a complex topic and, as described in this case, such accelerated treatment can be effective. This commentary focuses on the merits of such inadvisable use of potent antimicrobials amid the risk of diminishing valuable antimicrobial efficacy, albeit resulting in desirable patient outcomes.

Total hip arthroplasty is associated with significant postoperative pain. A psoas compartment block is superior to other regional techniques in analgesia post THA. However, traditional methods of delivery are associated with serious complications. We present a technique of a surgeon delivered lumbar plexus block through injection at the portion of the iliopsoas seen intraoperatively. We randomised fifty-three consecutive patients into two groups. The group that received the block had an increased period prior to requesting supplementary analgesia and lower overall pain scores. There were no adverse effects. We have demonstrated the analgesic efficacy of Psoas Compartment Block performed during surgical access for total hip arthroplasty. This technique should be considered in the analgesic regimen for 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