title: Functional outcomes of conservatively managed acute ruptures of the Achilles tendon.
abstract: OBJECTIVE
  This prospective cohort study aims to determine if the size of the tendon gap following acute rupture of the Achilles tendon shows an association with the functional outcome following non-operative treatment.
  
  
  METHODS
  All patients presenting within two weeks of an acute unilateral rupture of the Achilles tendon between July 2012 and July 2015 were considered for the study. In total, 38 patients (nine female, 29 male, mean age 52 years; 29 to 78) completed the study. Dynamic ultrasound examination was performed to confirm the diagnosis and measure the gap between ruptured tendon ends. Outcome was assessed using dynamometric testing of plantarflexion and the Achilles tendon Total Rupture score (ATRS) six months after the completion of a rehabilitation programme.
  
  
  RESULTS
  Patients with a gap ≥ 10 mm with the ankle in the neutral position had significantly greater peak torque deficit than those with gaps < 10 mm (mean 23.3%; 7% to 52% vs 14.3%; 0% to 47%, p = 0.023). However, there was no difference in ATRS between the two groups (mean score 87.2; 74 to 100 vs 87.4; 68 to 97, p = 0.467). There was no significant correlation between gap size and torque deficit (τ = 0.103), suggesting a non-linear relationship. There was also no significant correlation between ATRS and peak torque deficit (τ = -0.305).
  
  
  CONCLUSIONS
  This is the first study to identify an association between tendon gap and functional outcome in acute rupture of the Achilles tendon. We have identified 10 mm as a gap size at which deficits in plantarflexion strength become significantly greater, however, the precise relationship between gap size and plantarflexion strength remains unclear. Large, multicentre studies will be needed to clarify this relationship and identify population subgroups in whom deficits in peak torque are reflected in patient-reported outcome measures. Cite this article: Bone Joint J 2017;99-B:87-93.
authors.affiliation: Addenbrooke's Hospital, Department of Trauma and Orthopaedic Surgery, Addenbrooke's Hospital, Cambridge University NHS Foundation Trust, Hills Road, Cambridge, UK.
authors.forename: J E
authors.initials: JE
authors.lastname: Lawrence
authors.affiliation: Addenbrooke's Hospital, Department of Trauma and Orthopaedic Surgery, Addenbrooke's Hospital, Cambridge University NHS Foundation Trust, Hills Road, Cambridge, UK.
authors.forename: P
authors.initials: P
authors.lastname: Nasr
authors.affiliation: Addenbrooke's Hospital, Department of Trauma and Orthopaedic Surgery, Addenbrooke's Hospital, Cambridge University NHS Foundation Trust, Hills Road, Cambridge, UK.
authors.forename: D M
authors.initials: DM
authors.lastname: Fountain
authors.affiliation: Addenbrooke's Hospital, Department of Trauma and Orthopaedic Surgery, Addenbrooke's Hospital, Cambridge University NHS Foundation Trust, Hills Road, Cambridge, UK.
authors.forename: L
authors.initials: L
authors.lastname: Berman
authors.affiliation: Addenbrooke's Hospital, Department of Trauma and Orthopaedic Surgery, Addenbrooke's Hospital, Cambridge University NHS Foundation Trust, Hills Road, Cambridge, UK.
authors.forename: A H N
authors.initials: AH
authors.lastname: Robinson
mesh_terms: D000125:Achilles Tendon / Q000293:injuries*; D000359:Aftercare / Q000379:methods; D002370:Casts, Surgical; D005260:Female; D006801:Humans; D007103:Immobilization / Q000379:methods; D008297:Male; D053580:Muscle Strength / Q000502:physiology; D053581:Muscle Strength Dynamometer; D018482:Muscle, Skeletal / Q000502:physiology; D026741:Physical Therapy Modalities; D011446:Prospective Studies; D012421:Rupture / Q000628:therapy; D013708:Tendon Injuries / Q000503:physiopathology / Q000534:rehabilitation / Q000628:therapy*
keywords: Achilles tendon; Conservative management; Dynamometry; Functional outcomes; Ultrasound