Achilles Tendon Stiffness in the Etiology of Sever Disease: A Shear Wave Elastography Study.

BACKGROUND: Sever disease is one of the most common causes of heel pain in growing children and adolescents. There is no consensus about etiology of Sever disease. METHODS: The study comprised 41 participants aged 8 to 13 years who visited the orthopedic outpatient clinic: 17 patients with Sever disease and 24 asymptomatic children. The middle third segment of the body of the Achilles tendon and the calcaneal insertion zone were separately assessed. Five measuring points for the quantitative value of each point were randomly selected. The color scale used in the Young's modulus shows the lowest values in blue and the highest values in red. The mean values were used for the statistical analysis. RESULTS: Less elasticity was detected at the insertional site for the control group (4.02 kPa versus 3.65 kPa), the situation was reversed in the body of the Achilles tendon and the elasticity of the study group was less than that of the control group (241.0 kPa versus 260.5 kPa). However, no statistically significant difference was found between the groups. CONCLUSIONS: In conclusion, no difference was found in Achilles tendon elasticity between patients with Sever disease and healthy individuals in both the tendon body and the calcaneal insertionof the tendon. Achilles tendon elasticity has not been found to play a role in the etiology of Sever disease.

Comparison of Side-to-Side Difference in Posterior Tibial Slope in Knees With Acute Versus Chronic Anterior Cruciate Ligament Deficiency.

Background: The posterior tibial slope (PTS) is an important feature in knee joint biomechanics and indicates anterior-posterior knee stability. Increased PTS is a known risk factor for both primary anterior cruciate ligament (ACL) rupture and postreconstruction rerupture. Purpose: To investigate the effect of long-term exposure to ACL deficiency on the PTS and the sagittal anatomy of the proximal tibia. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A total of 44 patients (38 men, 6 women) with a history of knee injury and ACL rupture confirmed by magnetic resonance imaging and physical examination were included in this study. Patients were divided into those with chronic ACL deficiency (group 1: injured ≥5 years prior; n = 22) and acute ACL deficiency (group 2: injured <1 year prior; n = 22). The medial and lateral tibial plateau PTS and anterior tibial translation were measured on monopodal weightbearing knee radiographs at 20° of flexion. The mechanical tibiofemoral angle (MTFA) and the medial proximal tibial angle (MPTA) were measured using an orthoroentgenogram. The side-to-side difference between the affected and unaffected knees was also calculated for all measurements. Results: The mean duration of exposure to ACL deficiency was 7.6 years (range, 5-15 years) in group 1 and 4.4 months (range, 1-11 months) in group 2. Regarding the side-to-side differences in angular measurements, a higher medial PTS (affected vs unaffected: 12.4° vs 10.1°; P = .007), higher lateral PTS (11° vs 8.9°; P = .011), and increased varus alignment on both the MTFA (4.3° vs 2.4°; P = .036) and the MPTA (84.9° vs 86.3°; P = .033) were found in group 1, while no significant differences in angular measurements were found in group 2. Compared with group 2, patients in group 1 had a significantly higher side-to-side difference in the medial PTS (2.3° vs 0.1°; P = .0001), lateral PTS (2.1° vs 0.4°; P = .0001), and MPTA (1.4° vs 0.1°; P = .002). Conclusion: This study showed that the affected knees of patients with chronic ACL deficiency (≥5 years) had higher medial and lateral PTS compared with the unaffected contralateral knees. Therefore, when planning ACL reconstruction for patients with a history of long-term ACL deficiency, it is crucial to measure the preoperative PTS accurately.