ObjectiveThe purpose of this study was to evaluate the influence of a change in the meniscus cross sectional shape on its position and on the biomechanics of a knee joint.MethodsOne main finite element model of a left knee joint was created on the basis of MRI images. The model consisted of bones, articular cartilages, menisci and ligaments. Eight variants of this model with an increased or decreased meniscus height were then prepared. Nonlinear static analyses with a fixed flexion/extension movement for a compressive load of 1000 N were performed. The additional analyses for those models with a constrained medio-lateral relative bone translation allowed for an evaluation of the influence of this translation on a meniscus external shift.ResultsIt was observed that a decrease in the meniscus height caused a decrease in the contact area, together with a decrease in the contact force between the flattened meniscus and the cartilage. For the models with an increased meniscus height, a maximal value of force acting on the meniscus in a medio-lateral direction was obtained. The results have shown that the meniscus external shift was approximately proportional to the meniscus slope angle, but that relationship was modified by a medio-lateral relative bone translation. It was found that the translation of the femur relative to the tibia may be dependent on the geometry of the menisci.ConclusionsThe results have suggested that a change in the meniscus geometry in the cross sectional plane can considerably affect not only the meniscal external shift, but also the medio-lateral translation of the knee joint as well as the congruency of the knee joint.

BackgroundMeniscus extrusion is a serious and relatively frequent clinical problem. For this reason the role of different risk factors for this pathology is still the subject of debate. The goal of this study was to verify the results of previous theoretical work, based on the mathematical models, regarding a relationship between the cross-section shape of the meniscus and the risk of its extrusion.Materials and MethodsKnee MRI examination was performed in 77 subjects (43 men and 34 women), mean age 34.99 years (range: 18–49 years), complaining of knee pain. Patients with osteoarthritic changes (grade 3 and 4 to Kellgren classification), varus or valgus deformity and past injuries of the knee were excluded from the study. A 3-Tesla MR device was used to study the relationship between the shape of the lateral meniscus (using slope angle, meniscus-cartilage height and meniscus-bone angle) and the risk of extrusion.ResultsAnalysis revealed that with values of slope angle and meniscus-bone angle increasing by one degree, the risk of meniscus extrusion raises by 1.157 and 1.078 respectively. Also, an increase in meniscus-cartilage height by 1 mm significantly elevates the risk of extrusion. At the same time it was demonstrated that for meniscus-bone angle values over 42 degrees and slope angle over 37 degrees the risk of extrusion increases significantly.ConclusionsThis was the first study to demonstrate a tight correlation between slope angle, meniscus-bone angle and meniscus-cartilage height values in the assessment of the risk of lateral meniscus extrusion. Insertion of the above parameters to the radiological assessment of the knee joint allows identification of patients characterized by an elevated risk of development of this pathology.

High-pressure injection injury (HPII) is a rare severe hand trauma associated with high rates of complications and amputations of the peripheral parts of the fingers and permanent hand dysfunction. Early detection and treatment are crucial as any delay may result in a considerable functional deficit of the affected limb or amputation. The rate of amputation following HPII is 48%. This case report aims mainly to present the problem of HPII and general standards of management of such injuries. The routine use of supportive treatment in hyperbaric chambers, in the absence of contraindications, is also encouraged.

AbstractPurposeShoulder pain and weakness are common symptoms in athletes who play sports connected with overhead throwing. Suprascapular neuropathy may be one of the reason of such signs.The aim of the study was to find out if ultrasound examination of the shoulder in athletes reveals signs of suprascapular neuropathy.MethodsThis was a cross-sectional study in which 67 professional volleyball, handball and rugby players of polish teams without shoulder disorders, which have played sport for 10 or more years, were included. An ultrasound examination of both shoulders was performed. Excluding criteria were recent shoulder and/or neck trauma and neurological disorders.ResultsNo ultrasound signs of suprascapular neuropathy were seen in any player. The only finding was enthesopathy of supraspinatus muscle and this finding was connected with athletes’ age, type of sport and with dominant hand. It had statistical significance with p-value respectively 0.01 for athletes’ age, 0.0208 for sport type and 0.03 for dominant hand.ConclusionsUltrasonography should not be used as the screening examination of shoulders in athletes, but it can sometimes be an additional tool to help to diagnose shoulder disorders.