Patient characteristics and their impact on recovery after acute Achilles tendon rupture

Abstract

The incidence of acute Achilles tendon rupture has increased in the Swedish population. The median age at injury onset is roughly 50 years, with a male-to-female ratio of approximately 4:1. Acute Achilles tendon rupture is managed surgically or non-surgically. Several randomised controlled trials (RCTs) have been conducted to compare patients who received one of the two treatment interventions. The results demonstrate no significant differences in self-reported or functional outcomes between these treatment modalities. Complications occur following both treatment regimens. Wound-related complications, such as infections or nerve damage, may follow surgical treatment, whereas re-ruptures are more common after non-surgical treatment. Notwithstanding the robust results of these RCTs, a unified approach to personalise patient treatment remains elusive. To support the development of individualised treatment plans, five studies have been performed to address this issue. Studies I, II and III are based on patient-reported outcome measurements (PROMs). Patients who have sustained an acute Achilles tendon rupture were invited to complete the Achilles tendon Total Rupture Score (ATRS) and additional questions related to recovery, activity level and satisfaction after treatment. Study I investigated whether there were differences between men and women in self-reported outcomes. A total of 564 patients were included in the study, of which 129 (23%) were women. This study revealed that women self-reported significantly worse outcomes than men 1 to 6 years after injury. Study II evaluated the extent to which patients refrained from physical activity due to fear of re-injury to their Achilles tendon. In this study, 550 patients were included, of which 308 (56%) reported fear of re-injury. These patients also reported poorer self-reported outcomes compared to those who did not report a fear of re-injury. Study III aimed to establish the Patient Acceptable Symptom State (PASS) for the ATRS. The PASS is defined as patients’ self-reported perception of their well-being. The study comprised 316 participants; their responses to the anchor question and ATRS yielded a PASS value of 75 points for the Swedish ATRS. Calculations were conducted employing the receiver operating characteristic (ROC) curve. Study IV examined how the Achilles Tendon Resting Angle (ATRA) correlated with ultrasound (US) measurements at 6 and 12 months after an acute Achilles tendon rupture. Moreover, the correlations between the ATRA and other clinical measurements were evaluated. The study included 60 patients. The results demonstrated a significant correlation between relative ATRA and tendon elongation and between relative ATRA and heel-rise height. in each treatment modality suffered from a re-rupture. The functional and self-reported outcomes showed no statistically significant differences between the two treatment groups. Study V investigated whether the distance between the tendon ends after an acute Achilles tendon rupture - as a criterion for treatment selection - could influence functional and self-reported outcomes. In the patient group where the tendon gap (measured by US) was < 5 mm, non-surgical treatment was employed. Conversely, patients were treated surgically if the tendon gap was ≥ 5 mm. A total of 128 patients were included in the study, with 87 (68%) treated surgically and 41 (32%) treated non-surgically. One patient in each treatment modality suffered from a re-rupture. The functional and self-reported outcomes showed no statistically significant differences between the two treatment groups.In conclusion, this thesis shows that clinicians should be aware of the inferior outcome in female patients and patients who suffer from fear of re-injury following an acute Achilles tendon rupture. Moreover, establishing the PASS for the Swedish ATRS may facilitate improved clinical interpretation of ATRS scores. The correlation between ATRA and tendon elongation, evaluated with US, supports using ATRA to detect tendon elongation in the clinical setting. Furthermore, this thesis has contributed to our understanding of the tendon gap and its clinical relevance in selecting appropriate treatment following acute Achilles tendon rupture.