Bone marrow lesions in knee osteoarthritis assessed by dynamic contrast-enhanced MRI with histopathological correlations.

BACKGROUND: Bone marrow lesions (BMLs) in knee osteoarthritis (OA) have been assessed histopathologically and by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI); however, a direct comparison of the results has not been reported. PURPOSE: To evaluate and compare the findings by DCE-MRI and histopathology of subchondral BMLs in knee OA. MATERIAL AND METHODS: In total, 19 patients with medial tibiofemoral knee OA undergoing total knee arthroplasty were analyzed. Preoperative MRI, including a DCE sequence, was performed, and bone biopsies were obtained from the resected specimens corresponding to BML areas. The contrast enhancement by DCE-MRI was analyzed using semi-quantitative (area under the curve [AUC]), peak enhancement [PE]), and quantitative (Ktrans, Kep) methods. Enhancement in the medial OA compartment was compared with similar areas in a normal lateral compartment, and the DCE characteristics of BMLs were correlated with semi-quantitatively graded histopathological features. RESULTS: AUC and PE were significantly higher in medial tibial and femoral BMLs compared with the values in the lateral condyles; Ktrans and Kep were only significantly higher in the tibial plateau. In the tibia, AUC and PE were significantly correlated with the grade of vascular proliferation, and PE also with the degree of marrow fibrosis. There was no significant correlation between AUC/PE and histopathological findings in the femur and no correlation between quantitative DCE parameters and histopathological findings. CONCLUSION: BML characteristics by semi-quantitative DCE in the form of AUC and PE may be used as parameters for the degree of histopathological vascularization in the bone marrow whereas quantitative DCE data were less conclusive.

Feasibility, safety, and patient-reported outcomes 90 days after same-day total knee arthroplasty: a matched cohort study.

BACKGROUND AND PURPOSE: Despite increased attention to and acceptance of fast-track procedures, there is a lack of studies concerning discharge on the day of surgery (DOS) following total knee arthroplasty (SD-TKA). We evaluated the feasibility of SD-TKA, and compared safety and patient-reported outcomes (PROs) between patients undergoing SD-TKA and patients undergoing standard TKA. PATIENTS AND METHODS: A SD-TKA group (n = 101) was matched 1:1 to a standard TKA group (n = 101) on age, sex, and ASA score. Feasibility (being discharged on DOS), safety (unplanned contacts and complications evaluated by telephone calls (2 weeks), outpatient visits (2 weeks), and readmission (90 days)) were assessed. Further, Oxford Knee Score (OKS) and Visual Analogue Scale (VAS) (pain at rest and activity) were reported (90 days). RESULTS: 89 of 101 SD-TKA patients were discharged on DOS. The number of telephone calls (≤ 83) and outpatient visits (12) were similar in the 2 groups. The number of readmissions was ≤ 3 in both groups, and only 1 of the readmissions was related to TKA surgery. No differences were found at 90-day follow-up in terms of OKS (34 in both groups) or VAS (rest: SD-TKA = 7 and standard TKA = 8; activity: SD-TKA = 17 and standard TKA = 15). INTERPRETATION: SD-TKA is feasible in a selected group of patients, and safety and PROs are comparable to patients undergoing standard TKA.

Mobile- vs. fixed-bearing total knee replacement.

BACKGROUND AND PURPOSE: It is unclear whether mobile-bearing (MB) total knee arthroplasties reduce the risk of tibial component loosening compared to fixed-bearing (FB) designs. This randomized study investigated implant migration, periprosthetic bone mineral density (BMD), and patient-reported outcomes (Oxford knee score)-all at 2 years-for the P.F.C. Sigma Cruciate Retaining total knee arthroplasty. PATIENTS AND METHODS: 50 osteoarthritis patients were allocated to either FB or MB tibial articulation. RESULTS AND INTERPRETATION: At 2 years, the mean total translation (implant migration) was higher for the FB implant (0.30 mm, SD 0.22) than for the MB implant (0.17 mm, SD 0.09) (p = 0.04). BMD decreased between baseline and 1-year follow-up. At 2-year follow-up, BMD was close to the baseline level. The knee scores of both groups improved equally well. The FB tibial implant migrated more than the MB, but this was not clinically significant. The mobile polyethylene presumably partly absorbs the force transmitted to the metal tibial tray, thereby reducing micromotion.

Prognostic factors of knee pain and function 12 months after total knee arthroplasty: A prospective cohort study of 798 patients.

BACKGROUND: Approximately 20% of patients undergoing total knee arthroplasty (TKA) do not experience long-term improvements. Our aim was to identify prognostic factors of knee pain and function 12 months after TKA. METHODS: In a prospective cohort study, 1026 patients underwent primary TKA between 2018 and 2020. Main outcome was measured by the Oxford Knee Score (OKS) categorized in five categories (0-9, 10-19, 20-29, 30-39 and 40-48). Potential prognostic factors obtained at baseline included sex, age, baseline OKS, pain catastrophizing scale, EuroQol 5 dimensions, previous surgery, BMI, ASA classification, opioid consumption, living and employment conditions as well as educational level. Ordinal logistic regression analysis was used to identify prognostic factors of OKS. RESULTS: A total of 915 patients completed follow up (89%), and patients with complete data were included (n = 798). Patients with a baseline OKS between 10-19 and 20-29 had 2.5 (CI 1.6;4.0) and 1.6 (CI 1.1;2.4) higher odds, respectively, of no improvement or deterioration to a lower post-operative OKS category, compared with patients with a baseline score between 30 and 39. Female patients had 1.5 (CI 1.1;2.0) and patients receiving social benefits compared with retired patients had 2.0 (CI 1.1;3.5) higher odds of no improvement or deterioration to a lower OKS category. CONCLUSION: Baseline level of pain and function, sex and employment status were significant prognostic factors of OKS 12 months after TKA. Overall, the regression analysis only explained 4% of the outcome, indicating that it is difficult to predict 12-month TKA outcome prior to surgery.

Improving the referral pattern of patients with knee osteoarthritis to the orthopaedic surgeon: Development and evaluation of a new screening algorithm based on patient-reported data and radiographs.

INTRODUCTION: Many patients with knee osteoarthritis referred to orthopaedic surgeons are not eligible for surgery and might benefit from being examined by other healthcare professionals. The objective of this study was to develop and test a screening algorithm to define relevant referral to the OS. METHODS: Prior to clinical examination, 173 consecutive patients referred to the orthopaedic outpatient clinic completed questionnaires, and radiographic osteoarthritis severity was graded. The gold standard for relevant referral to an orthopaedic surgeon was based on actual treatment. The performance of the algorithm in predicting relevant referrals and total knee replacement (TKR) was assessed using sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). RESULTS: Referral to an orthopaedic surgeon was considered relevant in 65% (113/173) of patients. Sensitivity, specificity, PPV and NPV for predicting relevant referral to an orthopaedic surgeon were 0.70, 0.56, 0.76 and 0.48, respectively. The corresponding estimates for predicting TKR surgery were 0.92, 0.56, 0.55 and 0.92. CONCLUSIONS: The algorithm was able to identify most patients relevant for referral to an orthopaedic surgeon, but less suitable for identifying those not relevant. The algorithm demonstrated excellent performance in predicting TKR surgery. With further development, this screening algorithm might contribute to improvement of the referral pattern in the orthopaedic outpatient clinic.

Analgesia of Combined Femoral Triangle and Obturator Nerve Blockade Is Superior to Local Infiltration Analgesia After Total Knee Arthroplasty With High-Dose Intravenous Dexamethasone.

BACKGROUND AND OBJECTIVES: High-dose intravenous dexamethasone reduces the postoperative opioid requirement and is often included in the multimodal analgesia strategy after total knee arthroplasty (TKA). Combined obturator nerve and femoral triangle blockade (OFB) reduces the opioid consumption and pain after TKA better than local infiltration analgesia (LIA). The question is whether preoperative high-dose intravenous dexamethasone would cancel out the superior analgesic effect of OFB compared with LIA. The aim was to evaluate the analgesic effect of OFB versus LIA after TKA when all patients received high-dose intravenous dexamethasone. METHODS: Eighty-two patients were randomly assigned either to OFB or LIA after primary unilateral TKA. All patients received 16 mg dexamethasone. Primary outcome was morphine consumption via patient-controlled analgesia during the first 20 postoperative hours. Secondary outcomes were pain, nausea, dizziness, and length of hospital stay. RESULTS: Seventy-four patients were included in the analysis. Median total intravenous morphine consumption during the first 20 postoperative hours was 6 mg (interquartile range [IQR], 2-18 mg) in the OFB group and 20 mg (IQR, 12-28 mg) in the LIA group. The 14-mg difference (95% confidence interval, 6.4-18.0 mg) was significant (P < 0.001). There was no difference in pain score at rest at 20 hours postoperatively: 2 (IQR, 1-4) in the OFB group and 3 (IQR, 2-5) in the LIA group. CONCLUSIONS: Combined OFB reduces morphine consumption better than LIA after TKA even when all patients received high-dose intravenous dexamethasone. CLINICAL TRIAL REGISTRATION: This study was registered at ClinicalTrials.gov, identifier NCT02374008.

Missed injuries in a level I trauma center.

BACKGROUND: Major trauma presents major diagnostic and therapeutic problems. Any delay in providing the treatment necessary may lead to increased morbidity and mortality, prolonged length of hospital stay, and increased cost. This study was undertaken to determine the extent, contributing factors, and implication of missed injuries and relate them to the three surveys in a Danish Level I trauma center. METHODS: The records of all major traumatized patients admitted to the Odense University Hospital from January 1996 through December 1999 have been studied to determine the extent and type of missed injuries. The initial examination is carried out by the trauma team in the A&E department according to standard protocols. Resuscitation is carried out according to Advanced Trauma Life Support principles and details are documented in the patient journal and in a special trauma journal. RESULTS: Sixty-four of 786 patients (incidence, 8.1%) had 86 missed injuries. The missed injuries averaged 1.3 injuries per patient. There were 45 male and 19 female patients, with a median age of 33 years (range, 12-81 years). The median ISS was 17 (range, 4-50); 14%, 38%, and 48% of the injuries were missed in primary, secondary, and tertiary surveys, respectively. CONCLUSION: Our study demonstrates that missed injuries can occur at any stage of the management of patients with major trauma. Repeated assessments, both clinical and radiologic, are mandatory to diminish the problem. In initial assessment, one still has to treat the greatest threat to life before complete diagnosis of all injuries, but alertness to evolving injuries must remain throughout the patient's stay in hospital.