Title: Dramatic effects of a new home exercise to improve hip function for patients with osteoarthritis

Fukuoka Wajiro Hospital, Rheumatology and Arthritis Center
Kazuo Hayashi
Yuki Shiatsu Clinic
Teruo Ooyati

  1. The 2015 OARSI World Congress on Osteoarthritis , in Seattle, Washington, USA; April 30 - May 3, 2015.
  2. Purpose: An exercise program was developed to prevent or postpone surgery for patients with 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 to adduction contracture(Fig.1). Pelvic realignment exercise(Fig.2) and a back-and-forth figure 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 hip function for patients with OA.
  3. CKC exercise involving the hip abductors
    Fig. 1 CKC exercise involving the hip abductors
  4. An open kinetic chain (OKC) exercise to strengthen the hip abductors involves raising and lowering the leg on the affected side. During this exercise, tilting of the pelvis was noted in the 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 the coronal 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°and rests 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.
  5. Pelvic realignment exercise
    Fig. 2 Pelvic realignment exercise
  6. When the pelvis is tilted forward, the paths that muscles follow may differ from their anatomical 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 lateral position 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 and she maintains this position for 120 seconds.
  7. Back-and-forth figure 8 exercise
    Fig. 3 Back-and-forth figure 8 exercise
  8. A back-and-forth figure 8 exercise was developed to increase the restricted range of motion (ROM) of affected hip joints to more closely approximate the physiological ROM. This exercise better distributes the local load to more closely approximate its physiological distribution.
    The patient sits in a chair. She places both hands at the rear of the thigh on the affected side (the side with poor hip abduction). She supports her thigh with both hands and moves her thigh in 4 directions (to one side, to the other side, up, and down) inwards and outwards 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 a day.
  9. Methods: This new exercise program was undertaken by 1,077 patients with OA of the hip 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 for osteoarthritis of the hip and the American College of Rheumatology classification criteria for the classification and reporting of osteoarthritis of the hip. Criteria for exclusion were any previous surgeries in the lower limbs, taking analgesics (if even one time), have received chiropractic treatment or other hip therapy, or having previously undertaken this exercise program. Patients were guided by a physical therapist and supervised while exercising 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 at home.
    Two hundred and eighty-six subjects were divided into 2 groups, one with unilateral OA of the 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 arthritis of patients are shown in Table 1. Groups I and II were compared in terms of the Harris Hip Score (HHS), HHS pain score, pain on a numerical rating scale (NRS), range of motion (ROM), the hip open angle in Patrick’s test, and the maximum strength of hip abductors at the baseline and at the 3-month follow-up. The HHS and HHS pain score were compared at the 1-year follow-up. None of the subjects received analgesics. Data were collected from electronic medical charts and analyzed by the Clinical Research Support Center Kyushu.
    A paired t-test was used for statistical analysis. Stata ver. 13 (StataCorp., College Station, Texas) was used. P<0.05 was significant.
  10. Table 1 Baseline Characteristics of the patients studied
  11. K/L grade(N)
    No. females(%)age(years)K/L 1K/L 2K/L 3K/L 4
    GroupⅠ(N=154)133(86.4)56.5±14.357334222
    GroupⅡ(N=132)124(93.9)54.3±12.951293418
  12. GroupⅠ: 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°
  13. Results:
    Significant differences in the HHS, HHS pain score, pain on an NRS, the hip open angle in Patrick’s 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 in abduction, adduction, external rotation, and internal rotation while Group II had significant differences in flexion, abduction, and internal rotation (Table 3). Significant differences in the 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 Patrick’s test but were not noted among patients in 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 were noted at the baseline and at the 1-year follow-up (Table 2).
  14. 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
  15. Baseline3 monthsP value1 yearP value
    HHSGroup
    74.29
    ±
    17.76
    81.20
    ±
    14.95(N=154)
    <0.000187.08
    ±
    15.73(N=38)
    0.003
    Group
    65.52
    ±
    17.32
    76.80
    ±
    18.65(N=132)
    <0.000182.06
    ±
    16.39(N=33)
    <0.0001
    HHS pain scoreGroup
    26.10
    ±
    14.43
    31.70
    ±
    11.41(N=154)
    <0.000136.26
    ±
    10.92(N=38)
    0.004
    Group
    19.62
    ±
    13.03
    28.79
    ±
    13.295(N=132)
    <0.000131.70
    ±
    12.86(N=33)
    <0.0001
    NRSGroup
    4.32
    ±
    2.22
    3.21
    ±
    2.22(N=150)
    <0.0001
    Group
    4.88
    ±
    1.98
    3.61
    ±
    2.17(N=130)
    <0.0001
    Angle in Patrick's testGroup
    51.44
    ±
    17.51
    57.30
    ±
    17.82(N=111)
    <0.0001
    Group
    51.67
    ±
    17.80
    57.75
    ±
    15.26(N=102)
    <0.0001
    Muscle strength(Nm)Group
    41.70
    ±
    18.05
    48.16
    ±
    20.46(N=132)
    <0.001
    Group
    40.56
    ±
    16.82
    47.36
    ±
    19.87(N=118)
    <0.0001
  16. ★Angle in Patrick's test: the hip open angle in Patrick's test
    ★Hand Held Dynamometer was used for evaluation of muscle strength
  17. Table 3 Difference in ROM at baseline and follow-up at 3 months
  18. Baseline3 monthsP value
    flexionGroupⅠ109.38±18.61110.49±18.16(N=154)0.16
    GroupⅡ107.50±18.60110.65±19.65(N=132)<0.001
    extensionGroupⅠ10.93±7.4511.69±6.85(N=154)0.12
    GroupⅡ10.46±7.2511.38±7.29(N=132)0.14
    abductionGroupⅠ26.99±10.3828.64±9.78(N=154)0.009
    GroupⅡ25.08±10.4427.77±11.22(N=132)0.001
    adductionGroupⅠ10.20±4.9511.15±4.97(N=154)0.04
    GroupⅡ9.92±4.9010.73±4.41(N=132)0.1
    external rotationGroupⅠ34.41±11.8336.45±12.65(N=154)0.006
    GroupⅡ35.86±12.1537.30±12.29(N=132)0.07
    internal rotationGroupⅠ28.78±16.2130.46±17.02(N=154)0.04
    GroupⅡ28.57±16.1632.09±16.16(N=132)<0.0001
  19. Table 4 HHS evaluation according to the K/L grade
  20. Baseline3 monthsP value
    K/L grade 1GroupⅠ81.58±17.4787.93±11.086(N=57)0.003
    GroupⅡ71.73±15.3784.22±14.34(N=51)<0.0001
    K/L grade 2GroupⅠ75.28±17.1984.97±12.21(N=33)0.004
    GroupⅡ64.59±17.5480.52±15.37(N=29)<0.0001
    K/L grade 3GroupⅠ67.64±15.3174.05±14.45(N=42)0.03
    GroupⅡ60.13±17.2169.50±17.90(N-=34)0.002
    K/L grade 4GroupⅠ66.60±16.5069.15±17.47(N=22)0.26
    GroupⅡ55.25±17.1158.25±21.62(N-=18)0.6
  21. ★No change in the KL grade at the baseline and at the 1-year follow-up were noted.
  22. Table 5 HHS evaluation according to angle of the hip in Patrick's test
  23. Baseline3 monthsP value
    angle in Patrick's test <30°GroupⅠ76.67±18.9782.67±12.72(N=15)0.18
    GroupⅡ67.13±17.3274.40±20.74(N=15)0.008
    Angle in Patrick's test 30°-<50°GroupⅠ67.19±18.1373.11±17.52(N=37)0.04
    GroupⅡ56.81±18.8570.06±18.36(N=31)0.003
    Angle in Patrick's test <50°GroupⅠ76.17±17.2984.55±13.77(N=58)<0.001
    GroupⅡ70.85±14.4381.95±14.55(N=55)<0.0001
  24. ★Angle in Patrick's test: the hip open angle in Patrick's test
  25. 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.