Citation: Foot & ankle international, 2013, 34(5), 645-56
Author: Ajis A, Henriquez H, Myerson M
Abstract:
BACKGROUND: It is still unknown how ankle range of motion changes following total ankle
arthroplasty. This study was undertaken to more accurately address patient
expectations, guide postoperative rehabilitation, and improve our understanding
of how ankle range of motion changes with time.
METHODS: 119 total ankle replacements of 3 different prosthetic designs from 1 surgeon
were retrospectively examined and compared. Ankle dorsiflexion and plantar
flexion ranges of motion were calculated and analyzed preoperatively and
postoperatively at 6 weeks, 3 months, 6 months, and 1 year. The different ankle
replacement systems were analyzed individually and together to determine whether
trends were replicated.
RESULTS: No significant increase in ankle range of motion was found 6 months
postoperatively (P = .75). Mean combined postoperative range of motion did not
change significantly from 24.3 degrees at 1 year versus a preoperative mean of
22.7 degrees (P = .75). Mean dorsiflexion improved significantly at the 6-week
postoperative stage by 5.5 degrees (P < .001), whereas plantar flexion only
improved by 2.9 degrees (P = .06). Mean dorsiflexion improved from preoperative
levels by 5.4 degrees (P = .001), whereas mean plantar flexion decreased by 3.7
degrees (P = .004).
CONCLUSIONS: We found no notable improvement in ankle range of motion after 6 months
following total ankle arthroplasty. We also found a disproportionately higher
increase in dorsiflexion compared with plantar flexion following surgery and an
overall reduction in mean plantar flexion range compared with preoperative
values. Notwithstanding this discrepancy, total mean ankle range of motion 1
year postoperatively was similar to preoperative values. Reasons for the
discrepancy between dorsiflexion and plantar flexion are unclear.
LEVEL OF EVIDENCE: Level III, retrospective comparative study.
KEYWORDS: ankle, arthroplasty, dorsiflexion, motion, physiotherapy, plantar flexion,
range, rehabilitation, replacement, trend
