Use$of$Ankle$Resting$Angle$as$a$Surrogate$ … - Zellers_Ankle... · – Bmode$measurement$ of$tendon$elongation 3 – HeelXrise$test$forcalf$endurance4 ... HeelXrise...

Use  of  Ankle  Resting  Angle  as  a  Surrogate  for  Tendon  Elongation  in  Individuals  Following  Achilles  Tendon  Rupture

Jennifer  A.  Zellers,  DPT1Heather  Gotha,  MD2

Karin  Grävare Silbernagel,   PT,  PhD,  ATC1

1  University  of  Delaware,   Newark,  DE2  First  State  Orthopaedics,  Newark,  DE

Disclosure

NO  CONFLICT  TO  DISCLOSEUse  of  Ankle  Resting  Angle  as  a  Surrogate  for  Tendon  

Elongation  in  Individuals  Following  Achilles  Tendon  RuptureJennifer  A.  Zellers,  DPTHeather  Gotha,  MD

Karin  Grävare Silbernagel,  PT,  PhD,  ATCOur  disclosures  are  in  the  Final  AOFAS  Mobile  App.

We  have  no  potential  conflicts  with  this  presentation.

Background

• Tendon  elongation  following  Achilles  tendon  rupture  associated  with  poor  functional  outcome

• Measurement  of  tendon  length  requires  imaging  modalities

• Simple  method  to  assess  tendon  length  without  special  equipment  would  be  helpful  in  clinical  assessment  and  management  of  these  patients

Use  of  Ankle  Resting   Angle   as  a  Surrogate  for  Tendon  Elongation   in  Individuals   Following   Achilles   Tendon   Rupture

Background• Surrogate  measures  of  tendon  length:  Ankle  resting  angle

– Knee  extended1– Knee  flexed2

• Achilles  tendon  resting  angle  (ankle  resting  angle  with  knee  flexed)2– Related   to  heel-­‐rise   height   on  heel-­‐rise   test– Sensitive   to  change  over  time

• Ankle  resting  angle  has  not  been  validated  against  measurement  of  Achilles  tendon  length  using  imaging

Purpose  of  current  study:  validate  ankle  resting  angle  to  measurement  of  tendon  elongation  with  extended  field  of  view  B  mode  ultrasound  imaging

Use  of  Ankle  Resting   Angle   as  a  Surrogate  for  Tendon  Elongation   in  Individuals   Following   Achilles   Tendon   Rupture

Methods• Participants

– Inclusion:   Individuals  with  unilateral   Achilles   tendon   rupture  with  surgical  repair

– Exclusion:   Deep  wound  infection,   lumbar  radiculopathy   affecting  plantar  flexors

• Procedure– Ankle  resting   angle:  knee  flexed2,   knee  extended1– B  mode  measurement   of  tendon   elongation3– Heel-­‐rise   test   for  calf  endurance4

• Statistical  Analysis– Descriptive   statistics– Pearson  correlation   for  relationship   between   ankle  resting   angle  and  tendon  

elongation/heel-­‐rise   test   performance

Use  of  Ankle  Resting   Angle   as  a  Surrogate  for  Tendon  Elongation   in  Individuals   Following   Achilles   Tendon   Rupture

MethodsAnkle  resting  angle Ultrasound  measurement

Use  of  Ankle  Resting   Angle   as  a  Surrogate  for  Tendon  Elongation   in  Individuals   Following   Achilles   Tendon   Rupture

ICC  =  0.94

ICC  =  0.80

Results  – Descriptive  Statistics

Description Mean (SD),  N  =  25

Age 44.2  (13.6)  years

Time from  Injury 22.5  (39.1)  months

Relative   resting   angle   – knee  flexed -­‐5.4 (6.4)⁰

Relative   resting   angle   – knee  extended -­‐6.7  (8.8)⁰

Heel-­‐rise test   total  work  limb  symmetry   index 45.8  (23.8)%

Use  of  Ankle  Resting   Angle   as  a  Surrogate  for  Tendon  Elongation   in  Individuals   Following   Achilles   Tendon   Rupture

Results  – Relationship  Between  Ankle  Resting  Angle  and  Tendon  Elongation

Use  of  Ankle  Resting   Angle   as  a  Surrogate  for  Tendon  Elongation   in  Individuals   Following   Achilles   Tendon   Rupture

R  =  -­‐0.528,  p  =  0.008R  =  -­‐0.452,  p  =  0.027

Results  – Relationship  Between  Ankle  Resting  Angle  and  Calf  Endurance

Use  of  Ankle  Resting   Angle   as  a  Surrogate  for  Tendon  Elongation   in  Individuals   Following   Achilles   Tendon   Rupture

R  =  0.591,  p  =  0.006 R  =  0.197,  p  =  0.405

Discussion

• Both  ankle  resting  angle  with  knee  extended  and  knee  flexed  relate  to  tendon  elongation

• Ankle  resting  angle  with  knee  flexed  also  relates  to  performance  on  heel-­‐rise  test  for  calf  endurance– May  indicate  passive  tension  from  the  calf  also  affects  ankle  resting  angle

• Limitations:  cross-­‐sectional  design

Use  of  Ankle  Resting   Angle   as  a  Surrogate  for  Tendon  Elongation   in  Individuals   Following   Achilles   Tendon   Rupture

References  and  Acknowledgements1.  Ecker  TM,  Bremer  AK,  Krause  FG,  Müller   T,  Weber  M.  Prospective  Use  of  a  Standardized  Nonoperative Early  Weightbearing Protocol  for  Achilles  Tendon  Rupture:  17  Years  of  Experience.   Am  J  Sports  Med.  2016.2.  Carmont MR,  Gravare Silbernagel K,  Mathy A,  Mulji Y,  Karlsson J,  Maffulli N.  Reliability   of  Achilles   tendon  resting  angle  and  calf  circumference   measurement   techniques.   Foot  Ankle  Surg.  2013;19:245-­‐249.3.  Silbernagel KG,  Shelley  K,  Powell  S,  Varrecchia S.  Extended  field  of  view  ultrasound  imaging   to  evaluate  Achilles   tendon  length  and  thickness:  a  reliability   and  validity   study.  Muscles,  Ligaments  and  Tendons  Journal2.  2016;6(1):104-­‐110.4.  Silbernagel KGK,  Gustavsson A,  Thomeé R,  Karlsson J,  Thomee R,  Karlsson J.  Evaluation  of  lower   leg  function  in  patients  with  Achilles   tendinopathy.  Knee  Surgery,  Sport  Traumatol Arthrosc.  2006;14(11):1207-­‐1217.  

Use  of  Ankle  Resting   Angle   as  a  Surrogate  for  Tendon  Elongation   in  Individuals   Following   Achilles   Tendon   Rupture

R21AR067390University  of  Delaware  Research  FoundationFoundation  for  Physical  

Therapy