Transient synovitis of the hip in an adult.

Abstract: Transient synovitis of the hip is an acute and self-limited disease commonly seen in children. It is the most common cause of acute hip pain in children ages 3 to 10. It is not considered a disease of adults. It usually only affects one hip. The child may complain of pain that is much worse with walking and may actually walk with a limp. The symptoms usually improve in 4 to 5 days. Over-the-counter pain medicines (acetaminophen, ibuprofen) may help. There is usually no associated residual deficit. Currently, three cases in the literature report the same presentation and symptomatology in adults. We report the fourth case of acute hip pain in an adult that behaved in a way parallel to that seen in the pediatric population.

Key Words: hip joint, synovitis, hip pain

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Transient synovitis of the hip is an acute, self-limited, inflammatory disease commonly seen in children. It is the most common cause of acute hip pain in children aged 3 to 10 years. The disease causes arthralgia and arthritis secondary to a transient inflammation of the synovium of the hip. We present a case of transient synovitis in an adult. We are aware of only three publications suggesting that some cases of acute, isolated synovitis of the hip in adults may be equivalent to transient hip synovitis in children. (1-3)

Case Report

A 70-year-old male with a 1-year history of seropositive rheumatoid arthritis, as defined by American College of Rheumatology Criteria, was admitted to our facility on October 14, 2004 with complaints of sudden onset left hip pain for 2 days. The patient was taking the following maintenance medications: Plaquenil 200 b.i.d. and methotrexate 7.5 mg every week. His rheumatologist had recently prescribed 5 mg per day of prednisone which he had been on for 2 weeks before being admitted. He denied any joint trauma. There was no associated fever, chills or redness in the left hip joint area and no associated arthralgias in other joints. The pain was aggravated by movement such as walking and any activity that entailed weight bearing on the joint. He claimed the pain had started spontaneously and woke him up. He also claimed to have nocturnal pain.

On physical examination, range of motion at the left hip was painful in all directions, with 45 degrees of flexion and 0 degrees of internal and external rotation. There was no active synovitis in the other joints. He was unable to ambulate due to pain. X-ray of the joint was normal. The erythrocyte sedimentation rate was 23 mm/h (normal: 0-10 mm/h), the C-reactive protein (CRP) level was 16.7 mg/L (normal: 0.3-0.8 mg/dL), and the white blood count showed mild leukocytosis (10,910 leukocytes with 69.7% polymorphonuclear cells). Urine culture was negative. Magnetic resonance imaging (MRI) showed grade 1 left hip joint effusion. (4) No aspiration was performed despite rheumatology recommendation to obtain fluid for analysis and cultures.

At admission, the patient was placed on morphine for pain control, cyclobenzaprine at night for muscle spasms at the left hip joint area and the prednisone was increased to 40 mg a day. On the hospital day 2, his symptoms were 50% improved and he started ambulating with a walker. On the hospital day 3, he was 100% improved and was discharged home on p.o. prednisone. On follow-up at the rheumatology clinic 2 weeks later, the CRP level was 0.4 mg/L. He continues to be symptom free with a full range of motion in his left hip.

Discussion

Transient synovitis of the hip is a well-documented disease that is the most common cause of acute hip pain in children. It is a self-limited disease that is associated with pain and limitation of hip motion, arising without a clear precipitant and resolving gradually with conservative treatment. (5,6)

This case demonstrates acute onset hip pain with laboratory evidence of inflammation but negative tests for an infectious or rheumatic cause that occurred in an adult. All symptoms resolved within 2 days.

The differential diagnosis for this case includes transient synovitis, septic arthritis, crystal-induced arthritis and rheumatoid arthritis flare-up. Orthopaedics consultation concluded that arthrocentesis was not needed because of insufficient effusion to tap and the MRI did not show changes compatible with septic arthritis such as signal intensity changes in the bone marrow or osteomyelitis of the bone. The cultures were all negative, the leukocytosis resolved and the patient had improved 100% in 2 days. Although crystal-induced arthritis is still a consideration, gout in the hip is usually a very rare and late manifestation of longstanding gouty arthritis. Another consideration is hip synovitis related to rheumatoid arthritis. A rheumatoid arthritis attack is usually polyarticular and associated with synovitis in other joints. Our patient complained of arthralgia only in the left hip. His finger and hand joints did not show any active synovitis.

Our case resembles hip synovitis in childhood, which is a sudden-onset, acute, self-limited synovitis of unknown cause. A viral etiology has been suggested but remains unproven. It is not considered a disease of adults. To our knowledge, there are currently three cases in the literature that report the same presentation and symptomatology in adults. (5,6) We are reporting the fourth case of acute hip pain in an adult that behaved in a way parallel to that seen in the pediatric population.

Conclusion

We propose that transient hip synovitis must exist in adults that parallels or is equivalent to that occurring in children. Adult patients are usually elderly (older than 60 yr), present with an acute onset hip pain associated with limited passive range of motion and show remarkable resolution of symptoms in 2 to 3 days. The diagnosis is one of exclusion. Septic arthritis should be ruled out. Treatment should consist of pain medications and early walking.

References

1. Laroche M, Moineuse C, Constantin A, et al. Do adults develop transient synovitis of the hip? Three case reports. Joint Bone Spine 2000;4:350-352.

2. Nyska M, Buskila D, Howard CB, et al. Benign synovitis of the hip in adults. Br J Rheumatol 1993;32:820-821.

3. Dzioba RB, Barrington TW. Transient monoarticular synovitis of the hip joint in adults. Clin Orthop 1977;126:190-192.

4. Lee SK, Suh KJ, Kim YM, et al. Septic arthritis versus transient synovitis at MR imaging. Radiology 1999;211:459-465.

5. Ehrendorfer S, LeQuesne G, Penta M, et al. Bilateral synovitis in symptomatic unilateral transient synovitis of the hip: an ultrasonographic study in 56 children. Acta Orthop Scand 1996;67:149-152.

6. Hart JJ. Transient synovitis of the hip in children. Am Fam Physician 1996;54:1587-1591, 1595-1596.</p> <pre> Every artist dips his brush in his own soul, and paints his own nature into his pictures. --Henry Ward Beecher </pre> <p>Anna Marie Quintos-Macasa, MD, Leonard Serebro, MD, and Yamini Menon, MD

From the Department of Rheumatology, Ochsner Clinic Foundation, New Orleans, LA.

Correspondence should be sent to Leonard Serebro, MD, 1514 Jefferson Highway, New Orleans, Louisiana 70121. Email: [e-mail].

Accepted August 24, 2005.

RELATED ARTICLE: Key Points

* Transient synovitis of the hip is an acute and self-limited disease commonly seen in children.

* We present a case of transient hip synovitis in an adult. Only 3 publications indicate that some cases of acute, isolated synovitis of the hip in adults may be the equivalent of transient hip synovitis in children.