Incidence and related factors for intraoperative failed spinal anaesthesia for lower limb arthroplasty.

BACKGROUND: Spinal anaesthesia is the preferred choice for total hip- and knee arthroplasty (THA/TKA), due to the claimed superior outcome profile, relative simple technique and without the need for advanced airway support. However, choosing and informing about spinal anaesthesia should also include the risk for intraoperative failed spinal anaesthesia with associated pain, discomfort and suboptimal settings for airway management. Small-scale studies suggest incidences from 1 to 17%; however, no multi-institutional large data exists on failed spinal incidence and related factors during THA/TKA, hindering evidence-based information and potential anaesthesia stratification. METHODS: In a sub-analysis, data from a prospective study on spinal anaesthesia for THA/TKA were examined for incidence of intraoperative conversion to general anaesthesia. Potential perioperative factors (age, gender, American Society of Anaesthesiologist (ASA) score, height, weight, BMI, procedure, bupivacaine dosage and duration of time from spinal administration until end of surgery) were analysed with logistic regression for relation to failed spinal anaesthesia. RESULTS: In all, 1451 patients were included for analysis, whereof 57 (3.9%) had failed spinal anaesthesia. Spinal failure patients were significantly younger (61 vs. 67 years, P = 0.003), and operation time longer in the failed spinal group vs no-failure, respectively (133 vs. 89 min, P < 0.001). No significant differences were found with regard to bupivacaine volume, gender, ASA-score, height, weight, BMI or THA vs. TKA. CONCLUSION: Failed spinal anaesthesia for THA and TKA is a relatively frequent occurrence and identification of risk patients is not feasible. These results should be considered when choosing anaesthesia and included in the information to patients.

[Partial or full component exchange in hip revision? : The relevance of off-label use and mix & match]. / Partieller oder vollständiger Wechsel in der Hüftrevisionsendoprothetik? : Bedeutung von Off-Label-Anwendung und Mix & Match.

Off-label use is frequently practiced in hip revision arthroplasty, as there may be indications for the application of implants for purposes outside the one the manufacturers intended (i.e. large bone and soft tissue defects, obesity). Patients may also benefit from selective application of mix & match in hip revision, when the exchange of one component only is necessary and the invasiveness of surgery can be reduced. Currently, there are no formal guidelines for these situations. Therefore, within a recent EFORT initiative, evidence- and consensus-based recommendations have been developed for the safe application of off-label use and mix & match in revision hip and knee arthroplasty.

Improved clinical investigation and evaluation of high-risk medical devices: the rationale and objectives of CORE-MD (Coordinating Research and Evidence for Medical Devices).

In the European Union (EU) the delivery of health services is a national responsibility but there are concerted actions between member states to protect public health. Approval of pharmaceutical products is the responsibility of the European Medicines Agency, whereas authorizing the placing on the market of medical devices is decentralized to independent 'conformity assessment' organizations called notified bodies. The first legal basis for an EU system of evaluating medical devices and approving their market access was the medical device directives, from the 1990s. Uncertainties about clinical evidence requirements, among other reasons, led to the EU Medical Device Regulation (2017/745) that has applied since May 2021. It provides general principles for clinical investigations but few methodological details-which challenges responsible authorities to set appropriate balances between regulation and innovation, pre- and post-market studies, and clinical trials and real-world evidence. Scientific experts should advise on methods and standards for assessing and approving new high-risk devices, and safety, efficacy, and transparency of evidence should be paramount. The European Commission recently awarded a Horizon 2020 grant to a consortium led by the European Society of Cardiology and the European Federation of National Associations of Orthopaedics and Traumatology, that will review methodologies of clinical investigations, advise on study designs, and develop recommendations for aggregating clinical data from registries and other real-world sources. The CORE-MD project (Coordinating Research and Evidence for Medical Devices) will run until March 2024; here we describe how it may contribute to the development of regulatory science in Europe.

Early hemodynamic response to tibial osteotomy in rabbits: influence of indomethacin and prostaglandin E2.

The hemodynamic role of prostaglandins in the inflammatory phase of bone healing was studied on day 4 after creation of a nailed midtibial osteotomy in 40 rabbits, divided into groups of 10, treated with either indomethacin (oral dosage 10 mg/kg), subcutaneous (s.c.) prostaglandin E2 (PGE2) (dosage 1 mg/kg), or PGE2 infusion into the abdominal aorta (rate 20 ng/kg/min) for a 20-min period immediately before the animals were killed. The last group served as controls. Regional blood flow was measured by means of radioactive microspheres, and plasma volume was assessed by distribution of circulating [125I]fibrinogen. Neither indomethacin nor s.c. PGE2 treatment had any hemodynamic effects in the osteotomy area. PGE2 infusion caused increased blood flow in bone, bone marrow, and muscle of the lower limbs except in the osteotomy area. Thus, the influence of prostaglandins and indomethacin on bone healing of a rabbit midtibial osteotomy does not appear to be a direct vascular effect in the early healing phase.

The use of indomethacin to prevent the formation of heterotopic bone after total hip replacement. A randomized, double-blind clinical trial.

We studied the effect of indomethacin on the prevention of formation of heterotopic bone after total hip replacement. In a randomized, double-blind clinical trial involving 201 patients, 102 patients received twenty-five milligrams of indomethacin three times daily for the first six postoperative weeks, and the other ninety-nine patients received a placebo. One year after the operation, eighty-nine of those who had received indomethacin had no sign of heterotopic ossification, and the remaining thirteen had a grade-I lesion. In the group that had received a placebo, twenty-seven had no heterotopic ossification; twenty-four, a grade-I lesion; thirty, a grade-II lesion; and eighteen, a grade-III lesion. Significantly fewer patients who had received indomethacin had formation of heterotopic bone compared with those who had been given a placebo (chi-square test, p less than 0.0005). Only patients who had grade-III formation of heterotopic bone had a significant reduction in movement of the hip.

The stabilizing effect of the ligamentous structures in the sinus and canalis tarsi on movements in the hindfoot. An experimental study.

Three-plane kinesiology of hindfoot instability was studied after lesions to the ligamentous structures in the sinus and canalis tarsi in 20 amputation specimens. Neither a lesion of the cervical ligament nor of the interosseous talocalcaneal ligament resulted in an increase in the total range of movements above 2.6 degrees in any of the three planes. However, the percentage increase in the total range of movements after cutting of the ligaments was generally largest in the talocalcaneal joint compared to the increase in the total hindfoot joint complex. The largest percentage increase (43%) in the talocalcaneal joint occurred at dorsiflexion after cutting the interosseous talocalcaneal ligament. The demonstrated minor instability after experimental lesions of the ligamentous structures in the sinus and canalis tarsi may have a clinical identity in the sinus tarsi syndrome. Patients with that syndrome rarely present an objective hindfoot instability, although a major complaint is a feeling of hindfoot instability.

Long-term results of total condylar knee arthroplasty in rheumatoid arthritis.

We have reviewed at an average period of ten years the results of 71 consecutive primary arthroplasties with the Insall-Burstein total condylar knee prosthesis in patients with rheumatoid arthritis. Their mean age at surgery was 52 years (24 to 72). At follow-up the overall results (Hospital for Special Surgery knee rating score) were excellent or good in 77%, fair in 11% and poor in 11%. There was residual pain in only 5% of patients with prostheses in situ; 58% could walk more than 500 m, and the median range of motion was 108 degrees. Eight knees had been revised. Five underwent arthrodesis because of deep infection and three needed revision arthroplasty for mechanical loosening. The crude survival rate of the arthroplasties was 89%. The presence of radiolucency around the tibial component correlated significantly with the severity of residual pain.

Combined treatment with indomethacin and low-dose heparin after total hip replacement. A double-blind placebo-controlled clinical trial.

We studied the safety of combining the postoperative use of a non-steroidal anti-inflammatory drug with low-dose heparin. In a double-blind, placebo-controlled clinical trial we reviewed the complications in 235 patients after total hip replacement, all treated with low-dose heparin and either indomethacin or a placebo. The incidence and type of complications in the two groups were nearly equal; indomethacin-treated patients had no increase in complications related to bleeding. Postoperative bleeding into drains was marginally greater in the indomethacin group, although the difference was not statistically significant. We conclude that treatment with indomethacin and low-dose heparin after hip replacement does not significantly increase the bleeding or other complications. We also found that patients receiving indomethacin were mobilised an average of one day before those on placebo.

A custom-made prosthesis for the treatment of supracondylar femoral fractures after total knee arthroplasty: report of four cases.

Four supracondylar femoral fractures following total knee arthroplasty, two because of intraoperative notching of the anterior femoral cortex and two because of osteoporosis, were revised using a custom-made prosthesis with femoral condyle section. At 1-6 year follow-up (median 3 years) after the revision, all patients had an excellent clinical result, although 2 had a prolonged rehabilitation period because of severe osteoporosis. At roentgenographic examination, no signs of loosening of the prostheses at the cement-bone interface were present.

Dislocation of the elbow: an experimental study of the ligamentous injuries.

The stability of human cadaveric elbow specimens was investigated using an experimental apparatus. Posterior dislocation of the elbow could only be produced when a combined valgus and external rotatory torque was applied to the specimen. None of the elbows were dislocated during varus and internal rotatory torque or in the extreme positions. In ten elbow specimens with an experimentally produced posterior dislocation, simultaneous rupture of the anterior part of the medial collateral ligament and the annular ligament were the most frequent findings. A lateral collateral ligament tear was only seen in two cases. Posterior elbow dislocation seems to be due to a combined valgus and external rotatory stress to the semiflexed elbow, resulting in a bilateral ligamentous injury.

Heterotopic bone formation after total hip arthroplasty in patients with primary or secondary coxarthrosis.

Heterotopic bone formation was investigated in 392 Charnley low-friction total hip arthroplasties. A multivariate linear regression analysis was used to account for the influence of co-variables: sex, age at surgery, postoperative treatment with antiinflammatory drugs during at least the first 2 weeks, and previous ipsilateral hip surgery. A total of 232 hips had been treated for primary coxarthrosis, and 114 and 46 hips for secondary coxarthrosis due to congenital dislocation and fracture-dislocation of the hip, respectively. None of the hips with primary coxarthrosis previously had ipsilateral hip surgery, whereas 41 hips (36%) in patients with congenital dislocation of the hip and 28 hips (61%) in patients with fracture-dislocation of the hip had one or more ipsilateral surgical procedures prior to the arthroplasty. The sex ratio varied between the groups, with a male:female hip ratio of 1:1, 1:10, and 3:1 for the three groups, respectively. The risk of developing grades 2 or 3 heterotopic ossification after total hip arthroplasty were significantly higher in men, patients without postoperative treatment with antiinflammatory drugs, and patients above age 60. In contrast, the analysis documented that previous ipsilateral hip surgery and type of coxarthrosis did not influence lesion development, supporting the theory that a systemic, rather than local factor, is responsible for the development of heterotopic bone formation after total hip arthroplasty.

Early radiolucencies following cemented total hip replacement. Influence of postoperative treatment with indomethacin.

The influence of treatment with indomethacin in the first 6 postoperative weeks on the incidence of early loosening and radiolucencies following cemented total hip replacement were studied in 102 hips. Ninety-nine hips in 99 patients without postoperative antiinflammatory treatment served as control group. One year after surgery, two patients in the indomethacin group and five patients in the control group were suspected of having loosening of one or both prosthetic components. However, no patients had a revision. The lateral acetabular cement-bone interface most frequently showed a radiolucent line. Concerning the incidence of radiolucent lines in any acetabular or femoral cement-bone interface zone, no difference could be shown between the two groups. When evaluated 1 year after surgery, postoperative treatment with indomethacin does not increase the incidence of aseptic loosening or cement-bone interface radiolucencies in cemented total hip replacement.

[Registration under the diagnosis of traumatic hip luxation in the national registry]. / Landspatientregisterets registrering under diagnosen traumatisk hofteluksation.

A national study of patients treated on account of traumatic dislocation of the hip in Denmark in 1989 and 1990 revealed that 755 cases had been registered under this diagnosis in the National Patient Register. A review of case reports from 71 departments with 755 registered identity numbers in the National Patient Register demonstrated that 121 patients had been treated for traumatic dislocation of the hip during the same period, and that seven of these had not been registered via the National Patient Register. The remaining 605 patients (80%) had either sustained dislocation of a hip prosthesis or had congenital dislocation of the hip. It is concluded that the Danish National Register, in its present form is of no value whatsoever in registration of traumatic dislocation of the hip nor congenital dislocation of the hip or dislocation of a total hip prosthesis.

[Long-term results of total condylar knee alloplasty by the Insall-Burstein method. A follow-up after 9-11 years]. / Langtidsresultater af totalkondyl-knaealloplastik ad modum Insall-Burstein. 9-11 års opgørelse.

A total of 118 patients (164 knees) participated in this investigation. These consisted of 23 males (31 knees) and 95 females (113 knees). The average age was 63 years (24-80 years) and the average period of observation was 10 years (9-11 years). The patients were examined clinically and radiographically preoperatively and also 8-12 weeks postoperatively and at intervals of one year thereafter. The Hospital for Special Surgery knee rating scale was employed in the clinical assessment and The Knee Society recognized radiolucency index in the radiographic assessment. At the most recent control examination, 82% of the knees assessed showed excellent or good results, 9% had fair results and 9% poor. The median total score was 84 points (quartiles: 76 and 98). Complete freedom from pain or slight pain were found in 91%. The range of motion was increased by an average of 12 degrees. A considerable improvement in the walking ability was found. A significantly positive correlation was found between the varus positioning of the tibial component and the occurrence of translucent zones. Serious complications occurred in 10% but none proved fatal.

[Postoperative analgesia with morphine versus morphine and paracetamol. A double-blind clinically controlled study with a placebo]. / Postoperativ smertebehandling med morfin vs. morfin og paracetamol. En dobbeltblind klinisk kontrolleret undersøgelse med placebo.

The effect of paracetamol on the postoperative employment of morphine was investigated in a double-blind clinically controlled investigation with a placebo. The operations concerned were elective gynaecological laparotomies and hip replacements. During the first 60 hours postoperatively, the employment of morphine was reduced significantly in the patients who received paracetamol. Reductions of 16, 22 and 26% were concerned. The differences between the various types of operation were not significant. Patients for joint replacements who had been treated preoperatively with non-steroid anti-inflammatory preparations did not have any significantly greater consumption of morphine postoperatively but the reduction in consumption of morphine in the paracetamol group was significantly greater with a saving of 43%. Patients who had received treatment with morphine preparations preoperatively had significantly greater consumption of morphine postoperatively but the additive analgesic effect of paracetamol remained unchanged at approximately 25%.

The relationship between ultra-short telomeres, aging of articular cartilage and the development of human hip osteoarthritis.

INTRODUCTION: Ultra-short telomeres caused by stress-induced telomere shortening are suggested to induce chondrocyte senescence in human osteoarthritic knees. Here we have further investigated the role of ultra-short telomeres in the development of osteoarthritis (OA) and in aging of articular cartilage in human hips. MATERIALS AND METHODS: Cartilage was obtained from four different distances of the central weight-bearing area in human femoral heads (14 OA and 9 non-OA). Samples were split into three: one for quantification of ultra-short single telomeres by Universal STELA and mean telomere length measurement by Q-PCR; one for histological grading of OA, and one for immunohistochemical staining. RESULTS: Load of ultra-short telomeres increased closer to the central weight-bearing area and correlated with cartilage degradation in both OA and non-OA samples. Mean telomere length decreased with decreasing distance to the central weight-bearing area, however, unexpectedly increased in the most central zone. This increase was associated with immunohistochemical findings of cells expressing markers characteristic of progenitor-like cells. CONCLUSION: These findings suggest a role of short telomeres in the development of OA and in aging of articular cartilage. Furthermore, progenitor-like cells with long telomeres may be recruited to the most damaged areas of the cartilage.