A population-based nationwide study of cruciate ligament injury in Sweden, 2001-2009: Incidence, treatment, and sex differences

Background: A few national cruciate ligament (CL) registers have been initiated with operative surveillance and outcome monitoring. No nationwide study describing CL injury has ever been done. Purpose: To study the incidence and characteristics of patients diagnosed with cruciate ligament injury in Sweden. Study Design: Descriptive epidemiology study. Methods: Data for all patients with a diagnosed CL injury between 2001 and 2009 were identified from the National Swedish Patient Register. Risk analysis and specific incidences were calculated according to age, sex, geographic region, and surgery. Results: A total number of 56,659 patients with CL injury were included in the study, and the overall incidence of CL injury in Sweden was 78 per 100,000 persons. Sixty percent of the patients were male. The mean age was 32 years (range, 1-98 years), and 50% of the cohort was younger than 30 years. There was an increased rate of injury among female patients younger than 20 years as compared with male patients in that age group. Among patients with CL injury, 36% underwent reconstructive surgery, with one-third of these performed within 1 year after injury. Among patients who underwent surgery, 59% were male; the mean age was 27 years (range, 5-89 years). Conclusion: This study defines the incidence of CL injury and also demonstrates sex differences in which men were more likely to sustain a CL injury, although female patients were injured at an earlier age. The findings in this study corroborate the results from recent surgical registers. Clinical Relevance: No data have hitherto been published including all patients with CL injury, treated both surgically and nonsurgically. Such baseline epidemiologic data are crucial to be able to validate and judge the generalizability of results from procedure registers and clinical studies. © 2012 The Author(s)

Mechanical properties during healing of Achilles tendon ruptures to predict final outcome: A pilot Roentgen stereophotogrammetric analysis in 10 patients

<p>Abstract</p> <p>Background</p> <p>There are presently few methods described for in vivo monitoring of the mechanics of healing human tendon ruptures, and no methods for prediction of clinical outcome. We tested if Roentgen stereophotogrammetric analysis (RSA) can be used to follow the restoration of mechanical properties during healing of ruptured Achilles tendons, and if early measurements can predict clinical results.</p> <p>Methods</p> <p>Achilles tendon repair was studied with RSA in 10 patients with a total rupture. Tantalum beads were implanted in conjunction with surgical repair. The patients were evaluated at 6, 12 and 18 weeks, and after 1 year. RSA was performed with two different mechanical loadings, and the strain induced by increasing load was measured. The transverse area was determined by ultrasound. CT scan at 12 weeks confirmed that the tantalum beads were located within the tendons. Functional testing was done after 1 year. A heel raise index was chosen as primary clinical outcome variable.</p> <p>Results</p> <p>The strain was median 0.90, 0.32 and 0.14 percent per 100 N tendon force at 6 weeks, 18 weeks and one year respectively. The error of measurement was 0.04 percent units at 18 weeks. There was a large variation between patients, which appears to reflect biological variation. From 6 to 18 weeks, there was a negative correlation between increase in transverse area and increase in material properties, suggesting that healing is regulated at the organ level, to maximize stiffness. Modulus of elasticity during this time correlated with a heel raise index at one year (Rho = 0.76; p = 0.02).</p> <p>Conclusion</p> <p>We conclude that the RSA method might have potential for comparing different treatments of Achilles tendon ruptures.</p

Function after anterior cruciate ligament injuries. Influence of visual control and proprioception

Information about limb positions and movements consists of input from visual, vestibular, cutaneous, muscular, tendinous and joint receptors, but the relative contribution from each type and location of receptors is not known. The aim of this study was: a) to measure the contribution from visual control on extremity function, as measured with a one-leg hop test in healthy persons, in patients with an asymptomatic ACL injury, after non-operative treatment and in patients with a stable knee after an ACL reconstruction, b) to investigate if there was any relation between proprioception from the extremity, as measured with the threshold for detecting passive motion of the knee, and the one-leg hop test with a gradual decrease in visual control. There was a decrease in hop-length when the subjects were deprived of visual control that was significant when the dominant eye or both eyes were blinded, both in the 2 patient groups and the reference population. The magnitude of the length reduction did not differ between the groups or between injured and healthy limbs. In all 4 threshold tests performed as a measure of peripheral proprioception, a stronger relation to hop-length was recorded for the blinded hop than with full visual control in the patients with nonoperated ACL injuries. The coefficients of correlation between hop-length and the proprioceptive recordings in the injured limb were of the same magnitude as on the healthy side