Background With an increase in deep vein thrombosis (DVT) following total knee arthroplasty (TKA) in the Asian population, most surgeons today use a form of prophylactic anticoagulant agents in patients after TKA. Nevertheless, DVT occasionally develops even in these patients with prophylaxis. The purpose of this study was to identify the risk factors for DVT after TKA in cases of postoperative low-molecular-weight heparin (LMWH) use. Methods We designed a retrospective study with 103 patients who underwent primary TKA. From the second postoperative day, 60 mg of LMWH was subcutaneously injected into the patients daily. On the seventh postoperative day, patients had computed tomography angiography to check whether they had DVT. Regarding risk factors, we investigated patients’ gender, age, surgical site (unilateral/bilateral), body mass index, method of anesthesia, preoperative hypertension, diabetes, hypercholesterolemia status, and prothrombin time/international normalized ratio from electronic medical records. We analyzed the statistical significance of these risk factors. Results Statistically significant factors in the single-variable analysis were surgical site (unilateral/bilateral), body mass index, preoperative hypertension status, and anesthesia method. Multiple logistic regression analysis with these factors revealed that the surgical site (unilateral/bilateral, p = 0.024) and anesthesia method (p = 0.039) were significant factors for the occurrence of postoperative DVT after TKA. Conclusions Patients undergoing simultaneous bilateral TKAs and patients undergoing TKA with general anesthesia need more attention regarding DVT even with chemoprophylaxis using LMWH after TKA.

Background: The goals of operative treatment for the adolescent athlete with unstable osteochondritis dissecans (OCD) lesion are rigid fixation and prevention of recurrence. Purpose: To evaluate clinical and radiological outcomes of internal fixation of lateral trochlear groove OCD with simultaneous lateral retinacular lengthening. Study Design: Case series; Level of evidence, 4. Methods: Adolescent athletes who had undergone internal fixation and simultaneous lateral retinacular lengthening for an unstable OCD lesion of the lateral trochlear groove were retrospectively reviewed. Subjective assessments included the Lysholm score, International Knee Documentation Committee (IKDC) subjective score, Tegner activity scale, and an athletic questionnaire. Functional tests included isokinetic muscle strength, single-leg hop for distance, single-leg vertical jump, and Y-balance. Pre- and postoperative radiographs and magnetic resonance images were reviewed. Results: The mean ± SD age of the 17 patients included in this study was 15.9 ± 0.9 years; last clinical follow-up duration was 37.7 ± 8.1 months. At the last follow-up, the Lysholm score improved from 68.7 ± 15.3 to 93.4 ± 12.4 and the IKDC subjective score from 60.2 ± 14.7 to 88.7 ± 12.7 ( P < .001). The mean Tegner activity scale score was 9.4 ± 0.5 before injury and 8.9 ± 1.2 at the last follow-up ( P = .059). The limb symmetry indices of isokinetic muscle strength, single-leg hop for distance, single-leg vertical jump, and Y-balance improved at the last follow-up; the mean limb symmetry index was ≥85% in each functional test. Regarding the athletic questionnaire, 16 (94.1%) patients were satisfied with the surgery. At the last follow-up, 2 patients had higher ability after returning to sports, 11 had the same ability, and 3 had lower ability than the preinjury level. Postoperative magnetic resonance imaging at 12-month follow-up showed that the OCD lesion appeared healed in 7 (41.2%) patients and partially healed in 9 (52.9%). Conclusion: Internal fixation of lateral trochlear groove OCD with simultaneous lateral retinacular lengthening in adolescent athletes achieved satisfactory clinical and radiological outcomes. Therefore, this combined surgical technique could be considered an effective treatment for lateral trochlear groove OCD, with a high rate of return to sport.