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- Schepull, Torsten, et al.
(författare)
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Early E-modulus of healing Achilles tendons correlates with late function : Similar results with or without surgery
- 2012
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Ingår i: Scandinavian Journal of Medicine and Science in Sports. - : John Wiley and Sons. - 0905-7188 .- 1600-0838. ; 22:1, s. 18-23
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Tidskriftsartikel (refereegranskat)abstract
- Non-operative treatment of Achilles tendon ruptures is associated with an increased risk of rerupture. We hypothesized that this is due to inferior mechanical properties during an early phase of healing, and performed a randomized trial, using a new method to measure the mechanical properties. Tantalum markers were inserted in the tendon stumps, and tendon strain at different loadings was measured by stereo-radiography (Roentgen stereophotogrammetric analysis) at 3, 7 and 19 weeks and 18 months after injury. Thirty patients were randomized to operative or non-operative treatment. The primary out-come variable was an estimate for the modulus of elasticity at 7 weeks. Strain per force, cross-sectional area and tendon elongation were also measured. The functional outcome variable was the heel-raise index after 18 months. There was no difference in the mean modulus of elasticity or other mechanical or functional variables between operative and non-operative treatments at any time-point, but strain per force at 7 and 19 weeks had a significantly larger variation in the non-operative group. This group, therefore, might contain more outliers with poor healing. The modulus of elasticity at 7 weeks correlated with the heel-raise index after 18 months in both treatment groups (r2=0.75; P=0.0001). This correlation is an intriguing finding.
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| 2. |
- Schepull, Torsten, et al.
(författare)
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Mechanical properties during healing of Achilles tendon ruptures to predict final outcome : A pilot Roentgen stereophotogrammetric analysis in 10 patients
- 2007
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Ingår i: BMC Musculoskeletal Disorders. - : Springer Science and Business Media LLC. - 1471-2474. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Background. 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. Methods. 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. Results. 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). Conclusion. We conclude that the RSA method might have potential for comparing different treatments of Achilles tendon ruptures. © 2007 Schepull et al, licensee BioMed Central Ltd.
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