Procollagen markers in microdialysate can predict patient outcome after Achilles tendon rupture

Abstract

ObjectivePatients who sustain acute Achilles tendon rupture (ATR) exhibit variable and mostly impaired long-term functional, and patient-reported outcomes. However, there exists a lack of early predictive markers of long-term outcomes to facilitate the development of improved treatment methods. The aim of this study was to assess markers of tendon callus production in patients with ATR in terms of outcome, pain, and fatigue.Study design and settingProspective cohort study; level of evidence 2. Outpatient orthopaedic/sports medicine department.PatientsA total of 65 patients (57 men, 8 women; mean age 41±7 years) with ATR were prospectively assessed.AssessmentsMarkers of tendon callus production, procollagen type I N-terminal propeptide (PINP) and procollagen type III N-terminal propeptide (PIIINP), were assessed 2 weeks postoperatively using microdialysis followed by enzymatic quantification. Normalised procollagen levels (n-PINP and n-PIIINP) were calculated as the ratio of procollagen to total protein content. Pain and fatigue were assessed at 1 year using reliable questionnaires Achilles tendon Total Rupture Score (ATRS).ResultsPatients exhibited fatigue (77.6%) and pain (44.1%) to some extent. Higher levels of n-PINP (R=0.38, p=0.016) and n-PIIINP (R=0.33, p=0.046) were significantly associated with less pain in the limb. Increased concentrations of PINP (R=−0.47, p=0.002) and PIIINP (R=−0.37, p=0.024) were related to more self-reported fatigue in the leg. The results were corroborated by multiple linear regression analyses.ConclusionsAssessment of procollagen markers in early tendon healing can predict long-term patient-reported outcomes after ATR. These novel findings suggest that procollagen markers could be used to facilitate the development of improved treatment methods in patients who sustain ATR.Trial registration numbersNCT01317160: Results. NCT02318472: Pre-results.

Increased mast cell degranulation and co-localization of mast cells with the NMDA receptor-1 during healing after Achilles tendon rupture

“…Patients afflicted by acute Achilles tendon rupture (ATR) also exhibit variable and long-term impaired outcomes such as pain and fatigue (Alim et al 2016).…”

Pyruvate and lactate as local prognostic biomarkers of patient outcome after achilles tendon rupture

“…The Achilles tendon and ankle functional and physical outcomes were evaluated by a physiotherapist at one year using the heel‐rise test (muscular endurance test) under MuscleLab® (Ergotest Technology) analysis. The limb symmetry index (LSI = (injured/uninjured) × 100) was calculated for heel‐rise height, repetitions, and total work …”

“…Recovery after injury is prolonged, and the long‐term outcome is variable. Thus, there is a need of predictive biomarkers, which could be used to optimize and individualize the treatment after tendon injuries . Tendon metabolism is controlling the healing potential via essential metabolites such as pyruvate .…”

“…During the last decade, microdialysis has emerged as a method to assess healing progression also in ATR . A small catheter placed in the biologically active part of the tendon, that is, paratenon, can capture the basic metabolites essential for energy demand and cell proliferation, which control the tendon healing process .…”

“…During the last decade, microdialysis has emerged as a method to assess healing progression also in ATR. [3][4][5] A small catheter placed in the biologically active part of the tendon, that is, paratenon, can capture the basic metabolites essential for energy demand and cell proliferation, which control the tendon healing process. 6,7 Microdialysis of the extracellular matrix followed by quantification of the molecules of interest has provided reliable and practical information concerning metabolism and the healing process in many human tissues.…”