Mismatch 'never events' in hip and knee arthroplasty: a cohort and intervention study.

AIMS: The aim of this study was to give estimates of the incidence of component incompatibility in hip and knee arthroplasty and to test the effect of an online, real-time compatibility check. MATERIALS AND METHODS: Intraoperative barcode registration of arthroplasty implants was introduced in Denmark in 2013. We developed a compatibility database and, from May 2017, real-time compatibility checking was implemented and became part of the registration. We defined four classes of component incompatibility: A-I, A-II, B-I, and B-II, depending on an assessment of the level of risk to the patient (A/B), and on whether incompatibility was knowingly accepted (I/II). RESULTS: A total of 26 524 arthroplasties were analyzed. From 12 307 procedures that were undertaken before implementation of the compatibility check, 21 class A incompatibilities were identified (real- or high-risk combinations; 0.17%; 95% confidence interval (CI) 0.11 to 0.26). From 5692 hip and 6615 knee procedures prior to implementation of the compatibility check, we found rates of class A-I incompatibility (real- or high-risk combinations unknowingly inserted) of 0.14% (95% CI 0.06 to 0.28) and 0.17% (95% CI 0.08 to 0.30), respectively. From 14 217 procedures after the introduction of compatibility checking (7187 hips and 7030 knees), eight class A incompatibilities (0.06%; 95% CI 0.02 to 0.11) were identified. This difference was statistically significant (p = 0.008). CONCLUSION: Our data presents validated estimates of the baseline incidence of incompatibility events for hip and knee arthroplasty procedures and shows that a significant reduction in class A incompatibility events is possible using a web-based recording system. Cite this article: Bone Joint J 2019;101-B:960-969.

Chronic pre-operative opioid use and acute pain after fast-track total knee arthroplasty.

BACKGROUND: Pre-operative opioid use has been suggested to increase post-operative pain and opioid consumption after total knee arthroplasty (TKA), but previous studies are either retrospective or inhomogeneous with regard to surgical procedures or control of analgesic regimes, or with few opioid-treated patients, hindering firm conclusions. METHODS: In a prospective observational study, we investigated the effect of > 4 weeks pre-operative opioid use [none vs. low dose (< 30 mg morphine equivalents (eq.)) vs. high dose (> 30 mg morphine eq.] in patients scheduled for primary, unilateral TKA. All patients had well-defined multimodal opioid-sparring perioperative analgesic therapy, and continued any pre-operative opioid medication. The primary outcome was differences between groups in pain at rest and during walk for the first 6 post-operative days. RESULTS: Among 123 patients included, 115 were available for final analysis (93% follow-up rate). Post-operative pain during walk was significantly increased in both opioid-treated groups vs. non-opioid-treated patients (P < 0.009). Secondary analysis of combining all pre-operatively opioid-treated patients vs. opioid-free patients, showed significantly increased pain at rest and walk and increased post-operative opioid requirement - excluding pre-operative dosage - during the first post-operative week in opioid-treated patients (P = 0.001 and P = 0.007, respectively). CONCLUSION: Pre-operative opioid use increases the risk for post-operative pain at rest and walk, and increased opioid consumption after TKA.

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.

[Knee alloplasty and working ability. The significance of knee alloplasty for working ability of patients who were working prior to surgery]. / Knaealloplastik og erhvervsevne. Knaealloplastiks betydning for erhvervsevnen hos patienter, der praeoperativt er i arbejde.

The effect of a total knee arthroplasty (TKA) on maintaining or restoring working ability for patients who preoperatively still were in active employment has not previously been reported. Between February 1989 and December 1990 a total of 926 patients (1024 knees) had the same type of TKA (AGC-2000) implanted at 14 different Danish hospitals. The patients were followed prospectively. Sixty-two patients (6.7% of the total material) were preoperatively registered as being still engaged in active employment. Follow-up after three years included 51 of these patients (with 62 knees). Fifty-eight percent were still working after three years compared to 79% after the first postoperative year. Only eight out of the 21 who quit their job during the follow-up period stated knee-trouble as being the direct cause. The most common reason for stopping work was ordinary age-determined pension. We found no correlation between the amount of occupational knee-load and the relative risk of not being able to continue working. Thus, four out of five patients who are employed preoperatively will generally be able to return to the same job within a year after a TKA.

Patient survival after total knee arthroplasty. 5-year data in 926 patients.

We analyzed prospectively the 5-year survival in 926 patients undergoing 1,024 total knee arthroplasties (TKA) in the period February 1989-December 1990. The patients were compared to an age- and sex-matched general population and to 326 patients operated on in the same period with total hip arthroplasty. Cox analysis showed that male sex, rheumatoid arthritis and complications within the first year increased the mortality rate in the TKA group. When this group was compared to the general population, only rheumatoid patients aged 65-74 years had an increased mortality. Generally, the TKA patients had a longer survival than the general population, especially women > 75 years old with arthrosis. The cumulative 5-year patient survival was 89%, both after hip and knee arthroplasty and was 81% in the matched general population.

[Autologous transfusion of drained blood in hip and knee alloplasty. A prospective controlled study of 56 patients]. / Autolog draenblodtransfusion ved hofte- og knaealloplastik. En prospektiv kontrolleret undersøgelse af 56 patienter.

Fifty-six patients undergoing hip or knee replacements were randomized to receive autologous drain-blood transfusion or homologous blood transfusion at postoperative need. A reinfusion of 65% of the postoperative drainage blood loss was achieved. The number of homologous blood transfusions fell concomitantly from 2.3 to 0.6 after hip replacement and from 3.3 to 0.3 after knee replacement. No signs of activation of the complement or coagulation systems were found.

Autotransfusion of drainage blood in arthroplasty. A prospective, controlled study of 31 operations.

56 consecutive patients who had primary arthroplasties of the hip or the knee were randomly selected for either autologous or homologous blood transfusion. For autologous transfusion, the Solcotrans Orthopaedic device was used. Patients who received autologous transfusion had 65 percent of the post-operatively drained blood reinfused; compared to the control group the number of bank blood transfusions decreased in the hip group from 2.3 to 0.6 units, and in the knee group from 3.3 to 0.3 units.

Spinal gas collection demonstrated at CT.

In 234 consecutive CT examinations of the lumbar spine, gas collection was observed in 4 cases with disk herniation, and in 6 cases of disk protrusion. In 3 cases free gas was found in the epidural space, and one patient presented an intraspinal gas-filled "bleb". Gas collection in intervertebral disk spaces and facet joints was found in a total of 60 patients. The CT findings and surgical results were compared to determine whether gas collection contributes to clinical symptoms. In most cases the presence of gas was not clinically important, but in one patient it presented as a spinal mass, causing pain and radiculopathy.