[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.

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.

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.

Biochemical markers of type II collagen breakdown and synthesis are positioned at specific sites in human osteoarthritic knee cartilage.

OBJECTIVE: To investigate whether type II collagen turnover markers used for osteoarthritis (OA) activity evaluation in body fluids can be detected at the level of specific histological features of OA cartilage tissue, as well as how they relate with each other at this level. METHODS: Adjacent sections were obtained from full-depth cartilage biopsies from 32 OA knees. Immunohistochemistry was performed for Helix-II and CTX-II, which are type II collagen fragments originating from the triple helix and the telopeptide region, respectively, and believed to reflect distinct breakdown events, as well as for type IIA N propeptide (PIIANP), a biochemical marker reflecting synthesis of type IIA collagen. RESULTS: Helix-II and CTX-II were detected in areas where collagen damage was reported previously, most frequently around chondrocytes, but also frequently in regions not previously investigated such as the margin area and close to subchondral bone, including vascularization sites and bone-cartilage interface. The latter is CTX-II's prevailing position and shows rarely Helix-II. PIIANP co-localized with Helix-II and CTX-II on a limited number of features, mainly in deep zone cartilage. Overall, our analysis highlights clear patterns of association of the markers with specific histological features, and shows that they spread to these features in an ordered way. CONCLUSION: Helix-II and CTX-II show to some degree differential selectivity for specific features in cartilage tissue. CTX-II detection close to bone may be relevant to the possible role of subchondral bone in OA. The restricted co-localization of breakdown markers and PIIANP suggests that collagen fragments can result only partially from newly synthesized collagen. Our study strengthens the interest for the question whether combining several markers reflecting different regional cartilage contributions or metabolic processes should allow a broader detection of OA activity.

Constrained liners for recurrent dislocations in total hip arthroplasty.

This study reports the results and complications from treating recurrent hip dislocations with a constrained liner (CL) after total hip arthroplasty (THA). Forty patients who had a CL inserted as a secondary prophylactic treatment were retrospectively reviewed after a median observation period of 27 months (range 7-77 months). During the observation period five patients had to be revised: one for deep infection and four on account of re-dislocations. Our results indicate that patients with recurrent THA dislocations can be treated with a CL and has a satisfactory low complication rate and a relatively low risk of re-dislocation.

Progressive Osteolysis after Porous-Coated Anatomic (PCA) Uncemented Total Hip Arthroplasty Ten-Year Results in 32 Consecutive Cases

ABSTRACT: Thirty-two primary non-cemented first generation Porous-Coated Anatomic (PCA) total hip prostheses in 31 patients were followed prospectively. The average follow-up period was 10.3 years. The median age at surgery was 53 years (range 21-65). All operations were performed by one surgeon. Preoperatively, all cases had a poor Harris Hip Score. Ten years after surgery, 95% were rated good or excellent. Progressive roentgenographical changes were observed. In particular there was severe femoral osteolysis in zones 1, 2 and 7, and extensive wear of the polyethylene liner at the two latest follow-up examinations. Wear of the polyethylene liner, up to 0.4 mm/year, was significantly correlated with osteolysis after seven years (p=0.003). Aseptic cup loosening was the reason for six of the eight failures. At 10.3 years after surgery the survival with revision as end-point was 72%. We stopped using the 1st generation PCA prosthesis after five years due to worrying roentgenographic changes. The seven and ten years results have confirmed that this prosthesis cannot be recommended for implantation. (Hip International 1999; 9: 214-20)

Indomethacin for prevention of heterotopic ossification. A randomized controlled study in 41 hip arthroplasties.

The effect of indomethacin 25 mg 3 times daily during the first 2 postoperative weeks in preventing heterotopic bone formation after cemented total hip arthroplasty was investigated in a randomized, double-blind and placebo-controlled clinical trial on 57 patients. 16 patients were secondarily excluded, leaving 19 patients in the indomethacin group and 22 patients in the placebo group. Evaluated from the 3-month radiographs, 18/19 indomethacin patients developed either no or only the milder Grade 1 ossification. In contrast, 11/22 placebo patients developed Grade 2 or 3 ossifications. Our observations favor indomethacin prophylaxis for 2 weeks in cemented arthroplasty of the hip.

Total condylar arthroplasty for gonarthrosis. A prospective 10-year study of 138 primary cases.

The results of 138 consecutive primary Insall-Burstein arthroplasties with an average observation period of 10 (9-11) years were assessed. Mean age at surgery was 71 (30-81) years. The patients were evaluated clinically, using the Hospital for Special Surgery knee rating scale, and radiographically, according to the radiolucency score of the Knee Society. At latest follow-up, the overall evaluation of the patients who completed the study was excellent or good in 86 percent, fair in 8 percent and poor in 6 percent. Residual functional pain was recorded in 12 percent of cases with prostheses in situ. An ability to walk more than 500 m was found in 62 percent. The median range of motion was 104 degrees. Arthrodesis was performed on 2 knees due to deep infection. There were 14 cases with substantial radiolucency around the prosthesis, but none of these patients had severe functional pain. The crude prosthetic survival rate was 98 percent. A correlation was found between the radiolucency score and both the total score and the intensity of the residual functional pain.

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.

[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.

Short-term treatment with nonsteroidal antiinflammatory medications to prevent heterotopic bone formation after total hip arthroplasty. A preliminary report.

The effect of short-term postoperative treatment with nonsteroidal antiinflammatory medication to prevent the formation of heterotopic ossification (HO) after total hip arthroplasty (THA) was studied in two groups of patients. Group A included 46 noncemented THAs in 40 men. Eight patients (13 hips) received prophylaxis with 25 mg of indomethacin three times daily for 14 days, and 32 patients (33 hips) received prophylaxis of 650 mg of aspirin twice daily for six weeks. Six to 12 months after surgery, only one hip (aspirin treated) developed HO, this being Grade I. In group B, 17 hips in 17 patients with cemented THA received prophylaxis of 25 mg of indomethacin three times daily. Of these, 12 patients were given indomethacin from one to nine days. One year after surgery, five hips had no HO and seven hips showed a Grade I or Grade II lesion. The remaining five patients in Group B received indomethacin from 19 to 26 days; one developed HO. This study demonstrated that treatment with either 650 mg of aspirin twice daily for six weeks or 25 mg of indomethacin three times daily for the first 14 postoperative days is sufficient to prevent the formation of severe HO after THA.

[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.

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.

Heterotopic bone formation following hip arthroplasty. A retrospective study of 65 bilateral cases.

Heterotopic bone formation after two-stage bilateral cemented total hip arthroplasty was evaluated in 65 patients (23 women and 42 men) who had not received treatment with antiinflammatory drugs in the immediate postoperative weeks. The mean age at the first operation was 65 years, and the median interval between the two arthroplasties was 3 months. Fifty-two patients developed heterotopic ossification after the initial hip arthroplasty. Of these patients, 40 also developed ossifications after contralateral hip arthroplasty. Out of 11 males developing Grade-III heterotopic ossification after the initial hip arthroplasty, 8 also developed Grade-III ossification after contralateral hip arthroplasty. Two females developed Grade-III ossification after the initial arthroplasty, but neither of them developed a Grade-III lesion after contralateral total hip arthroplasty. Males with Grade-III heterotopic ossification after the initial hip arthroplasty were shown to be at a high risk of developing the same severe lesion after contralateral total hip arthroplasty, making them candidates for postoperative prophylaxis.

Instability of the hindfoot after lesion of the lateral ankle ligaments: investigations of the anterior drawer and adduction maneuvers in autopsy specimens.

The mobility patterns in the tibiotalocalcaneal joint complex with a solitary lesion of the anterior talofibular ligament (ATL) and a combined lesion of the ATL and calcaneofibular ligament (CFL) were studied in 22 human lower-extremity autopsy specimens mounted in a kinesiologic testing device. A solitary lesion of the ATL increased the anteroposterior (AP) laxity in the ankle joint in the entire range of flexion, with a maximum median of 3.1 mm in neutral flexion. Further cutting of the CFL increased AP laxity most obviously in dorsiflexion. A solitary lesion of the ATL resulted in a minor instability in adduction, whereas further lesion to the CFL increased adduction in the entire range of flexion, with a maximum median of 14.2 degrees in dorsiflexion. The anterior drawer maneuver can reveal a combined lesion of the ATL and CFL if performed with the tibiotalocalcaneal joint complex in dorsiflexion. Significant clinical instability in adduction will only take place when a combined lesion of the ATL and CFL is present.

Total hip arthroplasty. The role of antiinflammatory medications in the prevention of heterotopic ossification.

Postoperative prophylaxis with antiinflammatory medications, primarily indomethacin, is extremely effective in preventing the severest degrees of heterotopic ossification (HO) after a total hip arthroplasty (THA) and the recurrence of excised HO developed after a previous hip surgery. Prophylaxis with indomethacin should be given in 25-mg doses three times daily for at least three weeks, starting on the first postoperative morning. However, a shorter treatment period may be equally effective in preventing the severest degrees of HO, and a postoperative delay of five days before the initiation of prophylaxis does not seem to be followed by the development of severe HO. As evaluated one year after surgery, treatment with antiinflammatory medications in the immediate postoperative weeks did not increase the incidence of implant-bone interface radiolucencies, aseptic loosening, or revisions in cemented or cementless THAs when compared with cases that did not have postoperative treatment. However, although no major complications have been reported regarding the use of antiinflammatory medications in the prevention of HO after THA, orthopedic surgeons prescribing such treatment should be aware of their contraindications as well as early and late side effects. Since several antiinflammatory agents are reported to be effective in preventing HO, future reports dealing with HO after THA should always include information about the postoperative antiinflammatory treatment used.