The pivot shift test is an important test following ACL reconstruction, and it correlates with functional outcomes.

No abstract

Background: Anatomic anterolateral ligament (ALL) reconstruction has been proposed to assist anterior cruciate ligament (ACL) reconstruction in controlling anterolateral rotational laxity of the knee. However, the biomechanical effects have not been reported. Purpose: (1) To investigate the effect of ALL transection on rotational knee kinematics and (2) to determine the effect on knee biomechanics of ALL reconstruction procedures compared with lateral extra-articular tenodesis (LET). Study Design: Controlled laboratory study. Methods: A total of 12 cadaveric knee specimens were tested in the following sequence: (1) ACLintact, (2) anteromedial bundle of ACL sectioned (ACLamb), (3) complete ACL sectioned (ACLfull), (4) ALL sectioned (ALLsec), (5) anatomic ALL reconstruction (ALLanat), and (6) LET. Biomechanical anterior drawer and Lachman tests were performed in which a 90-N load was applied to the posterior tibia, and anterior translation was measured. A combined load to simulate the early phase of the pivot-shift test was executed in which a 5-N·m internal rotation moment was applied to a fully extended knee; anterior translation and internal rotation were measured. Results: Anterior translation increased across conditions for the biomechanical tests. Internal rotation during the simulated early-phase pivot-shift test was significantly different between ACLfull and ALLsec. Anatomic ALL reconstruction did not significantly reduce internal rotation or anterior translation during the simulated early-phase pivot-shift test. After LET, a significant decrease in anterior translation was found. There was no evidence of overconstraint of the knee with either anatomic ALL reconstruction or LET. Conclusion:The ALL demonstrated a role in controlling anterolateral laxity. LET had a composite effect in governing both anterior and rotational laxity. Anatomic ALL reconstruction did not reduce anterolateral rotational laxity. Clinical Relevance: Profiling the biomechanical characteristics of anterolateral reconstruction is integral to understanding the implications and potential benefit of such an additional procedure to ACL reconstruction.

Background:Anatomic anterolateral ligament (ALL) reconstruction has been proposed to assist anterior cruciate ligament (ACL) reconstruction in controlling anterolateral rotational laxity of the knee. However, the biomechanical effects have not been reported.Purpose:(1) To investigate the effect of ALL transection on rotational knee kinematics and (2) to determine the effect on knee biomechanics of ALL reconstruction procedures compared with lateral extra-articular tenodesis (LET).Study Design:Controlled laboratory study.Methods:A total of 12 cadaveric knee specimens were tested in the following sequence: (1) ACLintact, (2) anteromedial bundle of ACL sectioned (ACLamb), (3) complete ACL sectioned (ACLfull), (4) ALL sectioned (ALLsec), (5) anatomic ALL reconstruction (ALLanat), and (6) LET. Biomechanical anterior drawer and Lachman tests were performed in which a 90-N load was applied to the posterior tibia, and anterior translation was measured. A combined load to simulate the early phase of the pivot-shift test was executed in which a 5-N·m internal rotation moment was applied to a fully extended knee; anterior translation and internal rotation were measured.Results:Anterior translation increased across conditions for the biomechanical tests. Internal rotation during the simulated early-phase pivot-shift test was significantly different between ACLfull and ALLsec. Anatomic ALL reconstruction did not significantly reduce internal rotation or anterior translation during the simulated early-phase pivot-shift test. After LET, a significant decrease in anterior translation was found. There was no evidence of over-constraint of the knee with either anatomic ALL reconstruction or LET.Conclusion:The ALL demonstrated a role in controlling anterolateral laxity. LET had a composite effect in governing both anterior and rotational laxity. Anatomic ALL reconstruction did not reduce anterolateral rotational laxity. Clinical Relevance: Profiling the biomechanical characteristics of anterolateral reconstruction is integral to understanding the implications and potential benefit of such an additional procedure to ACL reconstruction.

Using direct lateral fluoroscopy, radiographic landmarks of the ALL origin and insertion have been described.

No abstract

Angiomyofibroblastoma-like tumor (cellular angiofibroma) is a rare, circumscribed, slow-growing mesenchymal tumor that occurs predominantly in the vulva, perineum, and pelvis of women. We report two cases of this tumor in men arising as paratesticular masses of the scrotum, summarize the history of this tumor, and discuss why efforts should be made to differentiate it from aggressive angiomyxoma. Recommended treatment is complete surgical excision with long-term follow up exams, as local recurrence may occur many years after resection of the lesion.

Background: Patients infected with SARS-CoV-2 often develop venous and arterial thrombosis. The high patient mortality is partly attributed to thrombotic events. An emerging trend is the presence of immunological phenomena including antiphospholipid antibodies which may promote thrombosis. The mechanism for these observations is not clear though many patients with SARS-CoV-2 develop thrombocytopenia. Case presentation: We describe a patient with SARS-CoV-2 pneumonitis who presented with intermediate risk pulmonary embolism (PE). Careful attention to his daily platelet count suggested the possibility of immune mediated heparin-induced thrombocytopenia (HIT) which was confirmed by laboratory testing and resolved when anticoagulation was switched to a direct thrombin inhibitor. Conclusions: Since excessive platelet activation and in situ thrombosis occur in HIT, this case underscores the need to consider that thrombocytopenia in patients with SARS-CoV-2-most of whom receive heparinoids-may be unrecognized HIT. A central role for the platelet in the etiology of thrombosis during the COVID-19 pandemic should be explored.