Role of high tibial osteotomy in chronic injuries of posterior cruciate ligament and posterolateral corner

High tibial osteotomy (HTO) is a surgical procedure used to change the mechanical weight-bearing axis and alter the loads carried through the knee. Conventional indications for HTO are medial compartment osteoarthritis and varus malalignment of the knee causing pain and dysfunction. Traditionally, knee instability associated with varus thrust has been considered a contraindication. However, today the indications include patients with chronic ligament deficiencies and malalignment, because an HTO procedure can change not only the coronal but also the sagittal plane of the knee. The sagittal plane has generally been ignored in HTO literature, but its modification has a significant impact on biomechanics and joint stability. Indeed, decreased posterior tibial slope causes posterior tibia translation and helps the anterior cruciate ligament (ACL)-deficient knee. Vice versa, increased tibial slope causes anterior tibia translation and helps the posterior cruciate ligament (PCL)-deficient knee. A review of literature shows that soft tissue procedures alone are often unsatisfactory for chronic posterior instability if alignment is not corrected. Since limb alignment is the most important factor to consider in lower limb reconstructive surgery, diagnosis and treatment of limb malalignment should not be ignored in management of chronic ligamentous instabilities. This paper reviews the effects of chronic posterior instability and tibial slope alteration on knee and soft tissues, in addition to planning and surgical technique for chronic posterior and posterolateral instability with HTO

Stage-I osteochondritis dissecans versus normal variants of ossification in the knee in children

Background: Juvenile osteochondritis dissecans (OCD) has a better prognosis than the adult type. Objective : We postulated that the excellent prognosis of juvenile OCD could be explained, at least in part, by the erroneous diagnosis of some developmental variants of ossification as stage-I OCD. Materials and methods : Knee MRIs of 38 children, ages 7.5–17.7 years (mean and median age 13 years), were retrospectively reviewed to look for features that might separate normal variants of ossification from stage-I OCD. These included age, gender, site, configuration of the lesion, residual cartilaginous model and presence of edema. Results : Twenty-three patients (32 condyles) had ossification defects with intact articular cartilage suggestive of stage-I lesions. No stage-II lesions were seen in the posterior femoral condyles. Accessory ossification centers were seen in 11/16 posterior condyles and 3/16 central condyles. Spiculation of existing ossification was seen in 12/16 posterior condylar lesions and 1/16 central condyles. There was a predominance of accessory ossifications and spiculations in the patients with 10% or greater residual cartilaginous model. No edema signal greater than diaphyseal red-marrow signal was seen in the posterior condyles. Clinical follow-up ranged from 0.5 to 38 months, with clinical improvement in 22 out of 23 patients. Conclusion : Inclusion of normal variants in the stage-I OCD category might explain, in part, the marked difference in published outcome between the juvenile and adult forms of OCD. Ossification defects in the posterior femoral condyles with intact overlying articular cartilage, accessory ossification centers, spiculation, residual cartilaginous model, and lack of bone-marrow edema are features of developmental variants rather than OCD.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46719/1/247_2005_Article_1507.pd

The anterolateral ligament of the knee: unwrapping the enigma. Anatomical study and comparison to previous reports.

It has been suggested that the anterolateral ligament (ALL) of the knee may have importance in limiting rotational instability, and reconstruction may prevent a continued pivot-shift following anterior cruciate ligament surgery. However, the anatomy of this ligament has not been consistently reported in recent publications. We describe our experience of cadaveric dissection with reference to other published work.This article is freely available via Open Access. Click on the 'Additional Link' above to access the full-text from the publisher's site.Published (Open Access