Explant analysis of a Discocerv cervical disc: A case study for a ceramic-on-ceramic cervical disc.

Explant analyses are key to better understanding the effectiveness of medical implants in replacing natural joints. For the first time, an explanted Discocerv cervical disc was examined. The implant utilised the articulation of a caudal zirconia cup (inferior component) and a cephalic alumina head (superior component). The articulating surface of the superior alumina head had an average surface roughness of 0.016 ± 0.003 µm (Sa) and the articulating surface of the inferior zirconia cup had an average surface roughness of 0.015 ± 0.002 µm (Sa). Both articulating surfaces had negative skewness, indicating the removal of local peaks. The difference between the average surface roughness of the components was not significant (p-value: 0.741). Dark grey marks were observed on both of the articulating surfaces, which were found to be adhered titanium debris that was generated due to component impingement. This titanium debris may explain the small amount of metallosis that was reported at explantation. Some transfer of zirconium to the alumina articulating surface was also seen.

The Incidence of Venous Thromboembolism in Patients Undergoing Anterior Lumbar Interbody Fusion: A Proposed Thromboprophylactic Regime.

OBJECTIVE: To determine the safety and efficacy of the proposed venous thromboembolism (VTE) prophylaxis regime in patients undergoing anterior lumbar interbody fusion (ALIF) surgery. BACKGROUND: Deep vein thrombosis (DVT) and pulmonary embolism (PE) are recognized complications after spine surgery, with rates in the literature ranging from 0% to 14% with some form of prophylaxis. Pharmacological thromboprophylaxis can cause postoperative bleeding and hematomas, which can result in significant neural compromise or permanent injury, and wound complications. ALIF surgery involves the handling and compression of major abdominal vessels during surgery and this adds to the risk of both arterial thrombosis and VTE. METHODS: A retrospective review of data, which were prospectively collected to evaluate the incidence of VTE in 200 consecutive patients undergoing ALIF following our VTE prophylaxis protocol. All patients had low molecular weight heparin, tinzaparin 4500 units subcutaneously on the evening before surgery, then daily for 3 to 5 days, then aspirin (acetylsalicylic acid) 150 mg daily plus lansoprazole 30 mg daily for 4 weeks after surgery. All patients had intermittent pneumatic compression of their calves and thighs intraoperatively and for 24 hours postoperatively then had early mobilization and thromboembolic deterrent stockings for 6 weeks. RESULTS: There was no incidence of any symptomatic VTE in the any of the 200 patients and no loss to follow-up. There was a 0% incidence of injury to the iliac vessels, symptomatic arterial occlusion, wound hematoma, major intraoperative bleeding, need for transfusion, symptomatic GI bleed, or retroperitoneal hematoma requiring intervention. CONCLUSIONS: The proposed VTE prophylactic regime is safe and efficacious and may decrease the incidence of symptomatic VTE in patients undergoing an ALIF procedure, and despite the use of chemical thromboprophylaxis, there is no evidence of bleeding complications as a result of using this regime. LEVEL OF EVIDENCE: 4.

Novel bone grafting technique in stand-alone ALIF procedure combining allograft and autograft ('Northumbria Technique')-Fusion rate and functional outcomes in 100 consecutive patients.

INTRODUCTION: Successful ALIF surgery depends upon achieving solid fusion, whilst avoiding significant complications. Herein, we present the 'Northumbria Technique' of combining allograft with autograft in order to achieve solid interbody fusion. MATERIALS AND METHODS: A single-surgeon series of 100 consecutive patients undergoing stand-alone ALIF from 2016 to 2019 was studied. All had percutaneously harvested iliac crest bone graft (ICBG) dowels inserted into blocks of fresh frozen femoral head (FFFH) allograft, which were then inserted into the ALIF cages. Patients had dynamic radiographs at 4 months, CT at 6 months, and patient reported outcome measure scores (PROMS) throughout. RESULTS: One hundred patients (average age 44.8 years) were followed-up for an average of 29.1 months. Ninety-four (94%) patients were assessed as having fused on both CT and radiographs by an independent Radiologist. Three (3%) patients had abolition of movement on radiographs, but either lacked a CT scan or failed to meet Williams criteria for fusion. Two patients failed to attend for any imaging, so were considered not fused, and one patient had no evidence of fusion in either modality. There was a significant improvement in all PROMS. There were no intra-operative complications, and one patient had transient donor-site pain. CONCLUSIONS: The newly described 'Northumbria Technique' utilises the osteoconductive characteristics of the FFFH allograft, as well as the osteoinductive and osteogenic properties of the ICBG autograft. It gives high fusion rates (94-97%) and statistically significant improvements in PROMS, whilst avoiding the complications of harvesting a large amount of autograft and the huge costs of using synthetic agents.

Unexplained perioperative vertebrobasilar stroke in a patient undergoing anterior cervical decompression and disc arthroplasty.

BACKGROUND: Vertebrobasilar stroke associated with the anterior approach to the cervical spine is rare and has not been reported in cervical disc arthroplasty surgery. We report the case of a 60-year-old patient who underwent cervical disc arthroplasty at C4-5, C5-6 and C6-7. Postoperatively, due to symptoms and signs of a cerebellar stroke, magnetic resonance imaging of the brain was obtained confirming this diagnosis. Despite thorough investigation no specific identifiable cause for the stroke has been identified. We hypothesis an unrecognised period of intraoperative hypotension may have caused a temporary reduction in vertebrobasilar blood flow. METHODS: A retrospective review of the patient's case notes and a focused review of literature has been performed. RESULTS: Now two years postoperatively the patient has regained full power but has residual problems with balance. She has neuralgic pain down the right side of her body which following investigation is believed to result from the stroke. CONCLUSIONS / LEVEL OF EVIDENCE: Surgeons should be aware vertebrobasilar stroke is a possible rare perioperative complication associated with anterior cervical decompression and disc arthroplasty. Level V.

The effect of triclosan coated sutures on rate of surgical site infection after hip and knee replacement: a protocol for a double-blind randomised controlled trial.

BACKGROUND: 187,000 hip and knee joint replacements are performed every year in the National Health Service (NHS). One of the commonest complications is surgical site infection (SSI), and this represents a significant burden in terms of patient morbidity, mortality and cost to health services around the world. The aim of this randomised controlled trial (RCT) is to determine if the addition of triclosan coated sutures to a standard regimen can reduce the rate of SSI after total knee replacement (TKR) and total hip replacement (THR). METHODS: 2400 patients due to undergo a total hip or knee replacement are being recruited into this two-centre RCT. Participants are recruited before surgery and randomised to either standard care or intervention group. Participants, outcome assessors and statistician are blind to treatment allocation throughout the study. The intervention consists of triclosan coated sutures vs. standard non-coated sutures. The primary outcome is the Health protection Agency (HPA) defined superficial surgical site infection at 30 days. Secondary outcomes include HPA defined deep surgical site infection at 12 months, length of hospital stay, critical care stay, and payer costs. DISCUSSION: To date there are no orthopaedic randomised controlled trials on this scale assessing the effectiveness of a surgical intervention, particularly those that can be translated across the surgical specialities. The results from this trial will inform evidence-based recommendations for suture selection in the management of patients undergoing total hip or knee replacement. If triclosan coated sutures are found to be an effective intervention, implementation into clinical practice could improve long-term outcomes for patients undergoing hip and knee replacement. TRIAL REGISTRATION: Current Controlled Trials ISRCTN 17807356.

Are the claims made in orthopaedic print advertisements valid?

PURPOSE: Advertisements are commonplace in orthopaedic journals and may influence the readership with claims of clinical and scientific fact. Since the last assessment of the claims made in orthopaedic print advertisements ten years ago, there have been legislative changes and media scrutiny which have shaped this practice. The purpose of this study is to re-evaluate these claims. METHODS: Fifty claims from 50 advertisements were chosen randomly from six highly respected peer-reviewed orthopaedic journals (published July-December 2011). The evidence supporting each claim was assessed and validated by three orthopaedic surgeons. The assessors, blinded to product and company, rated the evidence and answered the following questions: Does the evidence as presented support the claim made in the advertisement and what is the quality of that evidence? Is the claim supported by enough evidence to influence your own clinical practice? RESULTS: Twenty-eight claims cited evidence from published literature, four from public presentations, 11 from manufacturer "data held on file" and seven had no supporting evidence. Only 12 claims were considered to have high-quality evidence and only 11 were considered well supported. A strong correlation was seen between the quality of evidence and strength of support (Spearman r = 0.945, p < 0.0001). The average ICC between the assessors' ratings was strong (r = 0.85) giving validity to the results. CONCLUSION: Orthopaedic surgeons must remain sceptical about the claims made in print advertisements. High-quality evidence is required by orthopaedic surgeons to influence clinical practice and this evidence should be sought by manufacturers wishing to market a successful product.

The effect of high dose antibiotic impregnated cement on rate of surgical site infection after hip hemiarthroplasty for fractured neck of femur: a protocol for a double-blind quasi randomised controlled trial.

BACKGROUND: Mortality following hip hemiarthroplasty is in the range of 10-40% in the first year, with much attributed to post-operative complications. One such complication is surgical site infection (SSI), which at the start of this trial affected 4.68% of patients in the UK having this operation. Compared to SSI rates of elective hip surgery, at less than 1%, this figure is elevated. The aim of this quasi randomised controlled trial (RCT) is to determine if high dose antibiotic impregnated cement can reduce the SSI in patients at 12-months after hemiarthroplasty for intracapsular fractured neck of femur. METHODS: 848 patients with an intracapsular fractured neck of femur requiring a hip hemiarthroplasty are been recruited into this two-centre double-blind quasi RCT. Participants were recruited before surgery and quasi randomised to standard care or intervention group. Participants, statistician and outcome assessors were blind to treatment allocation throughout the study. The intervention consisted of high dose antibiotic impregnated cement consisting of 1 gram Clindamycin and 1 gram of Gentamicin. The primary outcome is Health Protection Agency (HPA) defined deep surgical site infection at 12 months. Secondary outcomes include HPA defined superficial surgical site infection at 30 days, 30 and 90-day mortality, length of hospital stay, critical care stay, and complications. DISCUSSION: Large randomised controlled trials assessing the effectiveness of a surgical intervention are uncommon, particularly in the speciality of orthopaedics. The results from this trial will inform evidence-based recommendations for antibiotic impregnated cement in the management of patients with a fractured neck of femur undergoing a hip hemiarthroplasty. If high dose antibiotic impregnated cement is found to be an effective intervention, implementation into clinical practice could improve long-term outcomes for patients undergoing hip hemiarthroplasty. TRIAL REGISTRATION: Current Controlled Trials: ISRCTN25633145.

Systematic review of microendoscopic discectomy for lumbar disc herniation.

STUDY DESIGN: Systematic review. OBJECTIVE: To search and analyse randomised controlled trials (RCTs) published since the Cochrane review by Gibson and Waddell (2007) comparing microendoscopic discectomy (MED) with open discectomy (OD) or microdiscectomy (MD) and to assess whether MED improves patient-reported outcomes. Discectomy for symptomatic herniated lumbar discs is an effective operative treatment. A number of operative techniques exist including OD, MD, and MED. A 2007 Cochrane review identified OD as an effective treatment for symptom improvement, and found sufficient evidence for MD. However, evidence for MED was lacking. METHODS: A systematic review of Medline and Embase was carried out. Aiming to identify RCTs carried out after 2007, which compared OD with MD and MED which reported the Oswestry disability index (ODI) as an outcome. RESULTS: Four RCTs were identified. None of the studies found a significant difference in the ODI scores between study groups at any time point. Three studies compared MED to OD and one compared OD, MD, and MED. The largest study reported an increased number of severe complications in the MED group. CONCLUSIONS: There is some evidence to suggest that MED performed by surgeons skilled in the technique in tertiary referral centres is as effective as OD.

Cemented versus cementless hemiarthroplasty for intracapsular neck of femur fracture--a comparison of 60,848 matched patients using national data.

National guidelines recommend cemented hemiarthroplasty for intracapsular fractured neck of femur (NOF), based on evidence of less pain, better mobility and lower costs. We aimed to compare complications following cemented and cementless implants, using the national hospital episode statistics (HES) database in England. Dislocation, revision, return to theatre and medical complications were extracted for all patients with NOF fracture who underwent hemiarthroplasty between January 2005 and December 2008. To make a 'like for like' comparison all 30,424 patients with a cementless implant were matched to 30,424 cemented implants (from a total of 42,838) in terms of age, sex and Charlson co-morbidity score. In the cementless group, 18-month revision (1.62% versus 0.57% (OR 2.90, p<0.001)), 4-year revision (2.45% versus 1.11% (OR 2.28, p<0.001)) and 30-day chest infection (8.14% versus 7.23% (OR 1.14, p=0.028)) were significantly higher. Four-year dislocation rate was higher in cemented implants (0.60% versus 0.26% (OR 0.45, p<0.001)). No significant differences were seen in return to theatre or other medical complications. In this national analysis of matched patients mid-term revision and perioperative chest infection was significantly higher in the cementless group. This supports the published evidence and national guidelines recommending cement fixation of hemiarthroplasty.