Korean J Pain.  2011 Jun;24(2):93-99. 10.3344/kjp.2011.24.2.93.

Piriformis Syndrome in Knee Osteoarthritis Patients after Wearing Rocker Bottom Shoes

• Byeon GJ
• Kim KH

• KMID: 2074004
• DOI: http://doi.org/10.3344/kjp.2011.24.2.93

Abstract

BACKGROUND
Rocker bottom shoes (RBS) are popular among patients with different foot, leg, or back problems in Korea. Patients with knee osteoarthritis concurrent weakness in the quadriceps femoris muscle, who wear these shoes, are often assumed to develop piriformis syndrome (PS). This study was performed to improve the understanding about the effect of wearing such shoes on duration of the syndrome in knee osteoarthritis.
METHODS
We randomly assigned 150 patients with PS, who had used RBS daily for at least 6 months, to 2 groups, the S (stopped wearing) and K (kept wearing) groups. Both the groups were subdivided into the O and N groups, comprising patients with and without knee osteoarthritis, respectively. The effects of the treatment, including piriformis muscle injections and a home exercise program, were compared between the 2 groups by using a flexion-adduction-internal rotation (FAIR) test, a numeric rating scale (NRS), and the revised Oswestry disability index (ODI) during the 12-week follow-up.
RESULTS
The positive FAIR test ratios, mean NRS scores, and revised ODIs were higher in the KO group than the SN group from 4?12 weeks after treatment.
CONCLUSIONS
RBS may extend duration of the PS in osteoarthritis patients.

Keyword

back pain; gait disorders; knee osteoarthritis; piriformis syndrome; shoes

MeSH Terms

Back Pain
Foot
Humans
Knee
Korea
Leg
Muscles
Osteoarthritis
Osteoarthritis, Knee
Piriformis Muscle Syndrome
Quadriceps Muscle
Shoes

Figure

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  Fig. 1 Piriformis injection under fluoroscope. (A) Anteroposterior view, (B) Lateral view.

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  Fig. 2 A perform-at-home self-exercise program for piriformis muscle stretching. The exercise begins with a push- up position using hands and toes (A), followed by placing the affected leg across and underneath the body trunk so that, if possible, the affected knee is outside the trunk (B). The unaffected leg is extended straight back behind the trunk keeping the pelvis straight (C). The hips are moved backward toward the floor; the body is leant forward with the forearms toward the floor; the affected leg is kept in place, until a deep stretch is felt (D). The stretch is held for 30 s and then, the patient slowly returns to starting position.

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  Fig. 3 Changes in the positive flexion-adduction-internal rotation (FAIR) test ratios (A), the mean numeric rating scale (NRS) scores (B), and the mean revised Oswestry disability indices (ODIs) (%) (C), during the follow-up period in the 4 groups. *All variables were significantly higher in the KO group than in SN group (P < 0.05). †All variables were significantly higher in the KO group than in the SO group (P < 0.05).

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  Fig. 4 Changes in the positive flexion-adduction-internal rotation (FAIR) test ratios (A), the mean numeric rating scale (NRS) scores (B), and mean revised Oswestry disability indices (ODIs) (%) (C), during the follow-up period in the S and K groups. No difference was observed in treatment effectiveness between N and O groups (D?F). *All variables were significantly higher in the K group than in the S group (P < 0.05).

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