Title: Dramatic eﬀects of a new home exercise to improve hip function for patientswith osteoarthritis
Fukuoka Wajiro Hospital, Rheumatology and Arthritis Center
Kazuo Hayashi
Yuki Shiatsu Clinic
Teruo Ooyati

The 2015 OARSI World Congress on Osteoarthritis , in Seattle,
Washington, USA; April 30 - May 3, 2015.
Purpose: An exercise program was developed to prevent or postpone surgery for patientswith osteoarthritis (OA) of the hip. Worsening OA of the hip results in adduction
contracture of the hip and the pelvis tilting forward. A closed kinetic chain (CKC) exercise
involving the abductors was developed to prevent pelvic tilt in the coronal plane due toadduction contracture(Fig.1). Pelvic realignment exercise(Fig.2) and a back-and-forthﬁgure 8 exercise(Fig.3) were developed to halt worsening OA of the hip. The pelvic
realignment exercise and the back-and-forth ﬁgure 8 exercise were performed prior to a
CKC exercise involving the hip abductors as part of a new exercise program to improve hipfunction for patients with OA.

Fig. 1 CKC exercise involving the hip abductors
An open kinetic chain (OKC) exercise to strengthen the hip abductors involves raising andlowering the leg on the aﬀected side. During this exercise, tilting of the pelvis was noted inthe coronal plane. The abductors may not be active during this exercise, so a closed kinetic
chain (CKC) exercise involving the abductors was developed to prevent pelvic tilt in thecoronal plane due to adduction contracture.
The patient assumes a lateral position with the leg on her aﬀected side on top. She raises
the foot of her top leg to the height of her hip. She then moves the foot forward 5–10°andrests it on the pillow. She then sticks her heel out and holds that position for 15 seconds.
This exercise is performed 20 times a day.

Fig. 2 Pelvic realignment exercise
When the pelvis is tilted forward, the paths that muscles follow may diﬀer from theiranatomical paths. Failure to correct pelvic malalignment before a strengthening exercise
may exacerbate OA of the hip, so a pelvic realignment exercise was developed to do so.
This exercise corrects apparent diﬀerences in leg lengths. The patient assumes a lateralposition with her shorter leg on top. She then moves her top leg forward 30–45° and rests
her front foot on the ﬂoor. She moves her top shoulder back without lifting her leg up andshe maintains this position for 120 seconds.

Fig. 3 Back-and-forth ﬁgure 8 exercise
A back-and-forth ﬁgure 8 exercise was developed to increase the restricted range ofmotion (ROM) of aﬀected hip joints to more closely approximate the physiological ROM.
This exercise better distributes the local load to more closely approximate its physiologicaldistribution.
The patient sits in a chair. She places both hands at the rear of the thigh on the aﬀectedside (the side with poor hip abduction). She supports her thigh with both hands andmoves her thigh in 4 directions (to one side, to the other side, up, and down) inwards andoutwards to form a ﬁgure 8 pattern. The thigh is put through each loop of the ﬁgure 8(one loop inwards, 1 loop outwards) 15 times for each direction as a cycle. 1–3 cycles aday.

Methods: This new exercise program was undertaken by 1,077 patients with OA of thehip who visited this Hospital from April 2011 to January 2014. Subjects had hip pain for
longer than 3 months based on the Japanese Orthopaedic Association guidelines forosteoarthritis of the hip and the American College of Rheumatology classiﬁcation criteria
for the classiﬁcation and reporting of osteoarthritis of the hip. Criteria for exclusion wereany previous surgeries in the lower limbs, taking analgesics (if even one time), havereceived chiropractic treatment or other hip therapy, or having previously undertaken thisexercise program. Patients were guided by a physical therapist and supervised whileexercising once every 2 weeks. They were instructed to perform the exercises as a daily
routine at home. After 12 weeks, patients were instructed to perform the exercises daily athome.
Two hundred and eighty-six subjects were divided into 2 groups, one with unilateral OA ofthe hip (Group I) and another with bilateral OA of the hip (Group II). In Group II, the more
painful hip joint was analyzed. The sex, age, and Kellgren-Lawrence grade of joint arthritisof patients are shown in Table 1. Groups I and II were compared in terms of the Harris HipScore (HHS), HHS pain score, pain on a numerical rating scale (NRS), range of motion(ROM), the hip open angle in Patrickʼs test, and the maximum strength of hip abductors atthe baseline and at the 3-month follow-up. The HHS and HHS pain score were comparedat the 1-year follow-up. None of the subjects received analgesics.

Data were collectedfrom electronic medical charts and analyzed by the Clinical Research Support CenterKyushu.
A paired t-test was used for statistical analysis. Stata ver. 13 (StataCorp., College Station,Texas) was used. P<0.05 was signiﬁcant.
Table 1 Baseline Characteristics of the patients studied
K/L grade(N)No. females(%)

age(years)

K/L 1

K/L 2

K/L 3

K/L 4

GroupⅠ(N=154)

133(86.4)

56.5±14.3

57334222GroupⅡ(N=132)

124(93.9)54.3±12.9

51293418GroupⅠ: Group with unilateral OA of the hip (no pain in the opposite hip)GroupⅡ: Group with bilateral OA of the hip (pain in the opposite hip)★Patients with KL grade 1 arthritis had a Center-Edge angle smaller than 20°
Results:
Signiﬁcant diﬀerences in the HHS, HHS pain score, pain on an NRS, the hip open angle inPatrickʼs test, and maximum muscle strength of the hip abductors at the baseline and at
the 3-month follow-up were noted (Table 2). Group I had signiﬁcant diﬀerences inabduction, adduction, external rotation, and internal rotation while Group II had signiﬁcantdiﬀerences in ﬂexion, abduction, and internal rotation (Table 3). Signiﬁcant diﬀerences inthe HHS were noted for KL grades 1-3 at the baseline and at the 3-month follow-up but
not for KL grade 4 (Table 4). Signiﬁcant diﬀerences were noted among patients in Group II
with a hip open angle smaller than 30° in Patrickʼs test but were not noted among patientsin Group I. Signiﬁcant diﬀerences were noted for patients in Groups I and II who had a hip

open angle larger than 30° (Table 5).
Signiﬁcant diﬀerences in the HHS and HHS pain score of patients in Groups I and II werenoted at the baseline and at the 1-year follow-up (Table 2).
Table 2 Diﬀerence in HHS, HHS pain score, pain on an NRS, angle in Patrick's test,and muscle strength at the baseline and follow-up at 3 months and 1 year
Baseline

3 months

P value

1 yearP valueGroupⅠ

74.29±17.7681.20±14.95(N=154)<0.0001

87.08±15.73(N=38)

0.003

GroupⅡ

65.52±17.3276.80±18.65(N=132)<0.0001

82.06±16.39(N=33)<0.0001

GroupⅠ

26.10±14.4331.70±11.41(N=154)<0.000136.26±10.92(N=38)0.004

GroupⅡ

19.62±13.0328.79±13.295(N=132)<0.0001

31.70±12.86(N=33)<0.0001

GroupⅠ

4.32±2.22

3.21±2.22(N=150)<0.0001

GroupⅡ

4.88±1.98

3.61±2.17(N=130)<0.0001

GroupⅠ

51.44±17.51

57.30±17.82(N=111)<0.0001

GroupⅡ

51.67±17.8057.75±15.26(N=102)<0.0001

GroupⅠ

41.70±18.0548.16±20.46(N=132)<0.001GroupⅡ

40.56±16.8247.36±19.87(N=118)<0.0001

HHS

HHS painscore

NRSAngle inPatrick's test

Musclestrength(Nm)★Angle in Patrick's test: the hip open angle in Patrick's test
★Hand Held Dynamometer was used for evaluation of muscle strength
Table 3 Diﬀerence in ROM at baseline and follow-up at 3 monthsflexionextension

abduction

Baseline

3 months

P valueGroupⅠ109.38±18.61

110.49±18.16(N=154)

0.16GroupⅡ

107.50±18.60

110.65±19.65(N=132)<0.001

GroupⅠ

10.93±7.45

11.69±6.85(N=154)

0.12GroupⅡ

10.46±7.25

11.38±7.29(N=132)

0.14GroupⅠ

26.99±10.38

28.64±9.78(N=154)

0.009

GroupⅡ

25.08±10.44

27.77±11.22(N=132)

0.001

adduction

external rotationinternal rotation

GroupⅠ

10.20±4.95

11.15±4.97(N=154)

0.04GroupⅡ

9.92±4.90

10.73±4.41(N=132)

0.1

GroupⅠ

34.41±11.83

36.45±12.65(N=154)

0.006GroupⅡ

35.86±12.15

37.30±12.29(N=132)

0.07

GroupⅠ

28.78±16.21

30.46±17.02(N=154)

0.04GroupⅡ

28.57±16.16

32.09±16.16(N=132)<0.0001

Table 4 HHS evaluation according to the K/L grade

K/L grade 1

K/L grade 2

K/L grade 3

K/L grade 4Baseline

3 months

P valueGroupⅠ

81.58±17.47

87.93±11.086(N=57)

0.003

GroupⅡ

71.73±15.37

84.22±14.34(N=51)<0.0001

GroupⅠ

75.28±17.19

84.97±12.21(N=33)

0.004

GroupⅡ

64.59±17.54

80.52±15.37(N=29)<0.0001

GroupⅠ

67.64±15.31

74.05±14.45(N=42)

0.03GroupⅡ

60.13±17.2169.50±17.90(N-=34)

0.002

GroupⅠ

66.60±16.50

69.15±17.47(N=22)

0.26GroupⅡ

55.25±17.11

58.25±21.62(N-=18)

0.6★No change in the KL grade at the baseline and at the 1-year follow-up were noted.
Table 5 HHS evaluation according to angle of the hip in Patrick's test
Baseline

3 months

P valueangle in Patrick's test
<30°

GroupⅠ

76.67±18.97

82.67±12.72(N=15)

0.18GroupⅡ

67.13±17.32

74.40±20.74(N=15)

0.008

Angle in Patrick's test
30°-<50°

GroupⅠ

67.19±18.13

73.11±17.52(N=37)

0.04GroupⅡ

56.81±18.85

70.06±18.36(N=31)

0.003

Angle in Patrick's test
<50°GroupⅠ

76.17±17.29

84.55±13.77(N=58)<0.001

GroupⅡ

70.85±14.43

81.95±14.55(N=55)<0.0001★Angle in Patrick's test: the hip open angle in Patrick's test
Conclusions: This retrospective study revealed that this new home exercise program may
improve hip function for patients with OA of the hip. Plans are to conduct a prospective
controlled study to conﬁrm the eﬀectiveness of this program.