A LEG PRESS EXERCISE RESTORING SCREW-HOME MOVEMENT IMPROVES SHORT-TERM CLINICAL
OUTCOMES AFTER OPENING WEDGE HIGH TIBIAL OSTEOTOMY
+1,2Hanada, K; 1Hara, M; 1Fujiwara, A; 1Hanada, H: 2Gamada, K
+1Fukuoka Rehabilitation Hospital, Fukuoka, Japan, 2 Hiroshima International University, Hiroshima, Japan
[email protected]
INTRODUCTION:
High tibial osteotomy (HTO) is one of the most effective surgical
procedures as a management of medial compartment osteoarthritis (OA)
of the knee with varus alignment. Though opening wedge HTO
(OWHTO) using TomoFix (Synthes, Bettlach, Switzerland) theoretically
allows early full weight bearing, some patients demonstrates a delay in
achieving full weight bearing gait due to pain. This may be caused by
the fact that tibiofemoral rotational kinematics, i.e. screw-home
movement (SHM), are not restored in a HTO procedure １ . To restore
normal SHM in OA or HTO knees, the RRR (rotation restoration and
realignment) program has been proposed by one of the authors (KG)
using a leg press device that allows resisted tibial internal or external
rotation during leg pressing activity. We hypothesized that the RRR
program accelerates full weight bearing gait and improves clinical
outcomes after OWHTO.
METHODS:
An IRB-approved, single-blinded randomized control trial was
performed. Recruiting was carried out between August 2010 and March
2011 in our institution. Inclusion criteria were knee OA patients with
Kellgren & Lawrence classification of grade <3, aged >40, extension
motion deficit < 10°, and agreement of undergoing OWHTO. Exclusion
criteria were history of lower extremity trauma, fracture or surgery,
rheumatoid arthritis, and risk of internal medicine. Compartment
syndrome after HTO was excluded postoperatively because it is not
considered an effect of rehabilitation. All subjects signed an IRBapproved informed consent form prior to the enrollment. Subjects were
randomly allocated to the intervention group (LP group) or the control
group (CL group).
The LP group was assigned with the RRR program in which a leg
press activity in tibial internal rotation was performed using ReaLine
Leg Press (GLAB corp, Hiroshima, Japan) (Fig. 1). The CL group was
assigned with a quadriceps strengthening exercise without tibial rotation.
Both interventions were performed for 5 sets of 10 reps per day. In
addition, both groups performed standard rehabilitation program (ROM
ex, SLR) and icing to manage postoperative inflammation. The exercises
were started on the day before surgery to familiarize the subjects with
the exercises and restarted them on the day 3 (average) until the day 56
(average) postoperatively.
The outcome measurements were performed on the day before
HTO before and after the first intervention and at three months
postoperatively, which involved (a) timed 10m walking (10m walk), (b)
Timed Up and Go test (TUG), and (c) pain (/500 points) and activity
(/1700 points) scores in Western Ontario and McMaster University
(WOMAC). The number of the subjects who achieved full weight
bearing gait at one month after HTO was counted.
Statistical Analyses involved two-factor repeated measure
ANOVA and Tukey post hoc comparisons. The Level of significance
was set at p<.05.
RESULTS:
1. Subject demographics: The LP group involved 21patients (8 men,
13 woman, mean age 63 ± 3 years, mean BMI 25 ± 2 kg/m2), and the CL
group 21patients (6 men, 15 woman , mean age 65 ± 6 years, mean BMI
25 ± 5 kg/m2) without dropouts.
2. Immediate effect of the RRR program: As the immediate effects
of the single session of the RRR program preoperatively, the LP group
demonstrated improvements in the 10m walk by average 1.0 second (7.5
± 1.4 seconds to 6.5 ± 1.4 seconds (p=0.0001)) as well as in the TUG by
average 1.3 seconds (8.3 ± 1.8 to 7.0 ± 1.7 seconds (P=0.0001)).
3. Achieving full weight bearing gait at one month: The number of
the subjects who achieved full weight bearing gait at one month
postoperatively was accounted for 13 of 21 patients (61.9%) in the LP
and 4 of 21 patients (19%) in the CL groups.
4. Outcomes at three months: Significant advantages of the LP
group were found in the WOMAC pain score (p=0.003) (Fig. 2) and
WOMAC activity score (p=0.024) (Fig. 3). The LP group demonstrated
significant improvement (189 points (p=0.000)) as compared with the
CL group (64 points (p=0.126)) in the WOMAC pain score and
significant improvement (627 points (p=0.000)) as compared with the
CL group (218 points (p=0.024)) in the WOMAC activity score. No
statistical differences were observed in the 10m walk for both the LP
(p=0.750) and CL (p=0.832) groups nor in the TUG for both the LP
(p=0.201) and CL (p=0.880) groups.
DISCUSSION:
The LP group demonstrated improvements in the 10m walk and
TUG immediately after a single session preoperatively, greater number
of the subjects achieving full weight bearing gait at one month
postoperatively, and higher WOMAC pain and activity scores at three
months postoperatively.
Several positive studies have been found in literature regarding
outcomes after OWHTO2,3 Takeuchi et al.4 reported a rehabilitation
protocol that encourage full weight bearing gait within two weeks
postoperatively after OWHTO with hydroxyapatite insertion used in
osteotomy opening. Accordingly, OWHTO using Tomofix allows for
early weight bearing activities. The RRR program aiming at restoring
normal SHM accelerated pain reduction and achieving gait
postoperatively, suggesting that rotational realignment inside the knee
joint plays an important role in improving postoperative outcomes.
This study was a well-designed single-blinded RCT and the
outcomes were measured by a physical therapist. Only short-term
outcomes were measured and presented in this study. Therefore, we
conclude that the RRR program improves short-term clinical outcomes
after OWHTO.
SIGNIFICANCE
The RRR program is useful in improving clinical outcomes after
OWHTO. This further suggests that the RRR program may be effective
in reducing pain and improving function in the OA knees by restoring
normal SHM.
Figure 1: ReaLine Leg Press(GLAB corp)
Figure 2: WOMAC pain score Figure 3: WOMAC activity score
REFERENCES:
1.Takemae, Tet al.J Orthop Sci. 2006 Nov;11(6):601-6.
2. Kean, C. O et al .J Orthop Sports Phys Ther. 2011 Feb;41(2):52-9.
3. Niemeyer, P et al.Arthroscopy. 2008 Jul;24(7):796-804.
4. Takeuchi, R et al. Arthroscopy. 2009 Jan;25(1):46-53.
Poster No. 0853 • ORS 2012 Annual Meeting