title: Effect of posterior tibial tendon dysfunction on unipedal standing balance test.
abstract: BACKGROUND
  Foot pain and diminished functional capacity are characteristics of tibialis posterior tendon dysfunction (TPTD). This study tested the hypotheses that women with TPTD would have impaired performance of a unipedal standing balance test (USBT) and that balance performance would be related to the number of single limb heel raises (SLHR).
  
  
  METHODS
  Thirty-nine middle-aged women, 19 with early stage TPTD (stage I and II), were instructed to perform 2 tasks; a USBT and repeated SLHR. Balance success was defined as a 10-second stance. For those who were successful, center of pressure (COP) data in anterior-posterior (AP) and medial-lateral (ML) directions were recorded as a measure of postural sway. SLHR performance was divided into 3 bins (≤2; 3-9 and > 10 repetitions). The between-balance success on performing the SLHR test was analyzed using the Fisher's exact test (2 × 3). Independent t tests were used to compare between-group differences in postural sway. Relationship of postural sway to the number of heel raises was assessed using Spearman's rho.
  
  
  RESULTS
  The success rate of the USBT was significantly lower in women with TPTD than the controls (47% vs 85%, P = .041). In addition, women with TPTD who completed the USBT exhibited increased AP COP displacement (14.0 ± 7.4 vs 8.4 ± 1.3 mm, P = .008), and a strong trend of increased ML COP displacement (8.3 ± 4.5 vs 6.1 ± 1.2 mm, P = .050). The success rate of USBT was correlated with the number of SLHR (P = .01). The AP and ML COP displacement were correlated with SLHR (r = -.538 and .495), respectively.
  
  
  CONCLUSIONS
  Women with TPTD have difficulty in performing the USBT. Performance of the USBT and SLHR are highly correlated and predictive of each other.
  
  
  CONCLUSIONS
  A unipedal balance test may be used as a proxy TPTD assessment tool to the heel raising test when pain prevents performance.
  
  
  METHODS
  Level III, case control study.
authors.affiliation: Division of Biokinesiology & Physical Therapy, University of Southern California, Los Angeles, CA, USA.
authors.forename: Kornelia
authors.initials: K
authors.lastname: Kulig
authors.affiliation: Department of Physical Therapy, University of Nevada, Las Vegas, Las Vegas, NV, USA szu-ping.lee@unlv.edu.
authors.forename: Szu-Ping
authors.initials: SP
authors.lastname: Lee
authors.affiliation: Division of Biokinesiology & Physical Therapy, University of Southern California, Los Angeles, CA, USA.
authors.forename: Stephen F
authors.initials: SF
authors.lastname: Reischl
authors.affiliation: Division of Biokinesiology & Physical Therapy, University of Southern California, Los Angeles, CA, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Noceti-DeWit
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D005260:Female; D005413:Flatfoot / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D037081:Posterior Tibial Tendon Dysfunction / Q000503:physiopathology*; D004856:Postural Balance
keywords: balance; flat foot deformity; postural stability; tendon disorders; tibialis posterior