Affiliations: [a] Department of Physical Therapy, Tel-Aviv University,
Tel Aviv, Israel | [b] Department of Orthopedics, Sapir Medical center,
Kfar-Saba, Israel
Note: [] Address for correspondence: Prof. Zeevi Dvir, Department of
Physical Therapy, Sackler Faculty of Medicine, Tel Aviv University, 69978,
Israel. Tel.: +972 36405429; Fax: +972 36409223; E-mail: zdvir@post.tau.ac.il
Abstract: Background: Outcome measures of operative intervention for ankle
fractures indicate poor subjective and objective results. Though patients
regain full range of motion they often complain of pain and fatigability.
Specifically, there is a paucity of data regarding strength characteristics of
the relevant muscles after surgical intervention. Objective: Describe the strength characteristics of ankle invertors
(INs) and evertors (EVs) and explore their relationship to the ankle-hindfoot
scale (AHS) in patients after surgical intervention for ankle fractures. Method: Bilateral isokinetic concentric and eccentric INs and EVs
strength was measured in 24 patients, 6–12 months following surgery.
Additional subjective and objective factors were evaluated using the AHS. Results: Strength of the involved limb muscles was significantly
lower compared to the contra-lateral muscles (p<0.0001). However, strength
reduction was significantly greater in the INs (27.6–37.5%) than the EVs
(14.4–24.3%), (p=0.0005). The EVs/INs ratio of the uninvolved limb
(89–102%) was significantly lower than the ratio of the involved limb
(111–141%), (p<0.0001). The clinical status of the limb was found to
have a significant effect on all dynamic control ratios (DCRs): EVR(E)/INV(C),
INV(E)/EVR(C), EVR(C)/INV(E), and INV(C)/EVR(E) (P<0.0001, P=0.0032,
P=0.0001, and P=0.0015, respectively). A significant relationship was found
between the mean AHS score and relative unilateral weakness (r=−0.58,
p=0.003). Conclusions: Strength reduction could be one of the reasons for the
functional decline following ankle fractures. The weakness of the INs muscles
of the ankle is more pronounced than that of the EVs.
Keywords: Ankle fractures, muscle strength, dynamic control ratios, invertors, evertors
