TRANSIENT OSTEOPOROSIS OF HIP (TOH) DURING PREGNANCY. IS IT SO RARE? A CASE SERIES OF CLINICAL DIFFERENTIAL DIAGNOSIS

¹Sport & Spine PT Ltd., Physiotherapy, Ramat Gan, Israel

Background: Pelvic Girdle Pain (PGP) is a common phenomenon during pregnancy. Although it is often a benign phenomenon, some exceptions may exist. Transient Osteoporosis of the Hip (TOH) is one of them.
TOH is a rare, severe disorder of unknown etiology that typically occurs during the third trimester of pregnancy. The pathology involves high level of pain and considerable disability and is diagnosed by MRI. MRI findings may include diffuse femoral head bone marrow edema which extend to the femoral neck, and may or may not exhibit the signs of bone fractures.
Increased Physical activity, continued unprotected weight-bearing, and manual therapy techniques may increase the load on the fragile bone which worsens the condition by exposing the patient to risk for pathological hip fractures. There­fore, early diagnosis is crucial to prevent possible com­plications and medical malpractice.

Purpose: This presentation aims to increase Women Health and Musculoskeletal physiotherapist awareness by highlighting the clinical findings that would suggest “Red Flags” and need for further investigation.

Methods: This is a case series presentation of 10 patients with TOH who were clinically diagnosed in the PGP outpatient clinic during the last couple of years. The demographic data of those patients were collected to identify various factors which may have impact on the condition and the salient and important findings conclusive of the differential diagnosis are noticed. Physical examination by the log roll test was performed with the patient in supine and the hip in a neutral flexion/extension and abduction/adduction position. The Internal Rotation of Pelvis (IROP) was also performed when possible.

Results: Most significant clinical manifestation include difficulties in weight bearing due to pain, and significant reduction in range of motion of the Hip in the supine position especially toward internal rotation. Physical examination was continued with the Log Roll Test and when possible the IROP. The latter with sensitivity of 0.91 (95% CI 0.68-0.99) and low specificity for detecting Intra articular hip pathologies comparing it to the gold standard of Intra articular injection.
None of the patients in this series were able to reach the starting position for the IROP due to pain. All were tested and positive for pain and restricted movement in 0 degrees flexion, this is considered to be the less provocative position of the log roll test. Therefore, intraarticular pathology was suspected.
MRI confirmed TOH in all patients. Seven diagnosed with Femoral head fractures. One patient proceeded with a Total Hip Replacement due to Femoral head bone disruption.

Conclusions: Thorough physical examination with log roll test and IROP can be used as an excellent first-step screening tool, for early diagnosis of the severe pathology of TOH by a physiotherapist. This is the preferred option for clinical screening before an expensive MRI examination can be done to evaluate detailed pathologies.

Implications: This presentation aims to increase the awareness of this rare and severe pathology in an era where physiotherapy is gradually becoming a self-referral profession in increasing number of countries while the need to use essential physiotherapy practice to screen our PGP patients increases.

Funding acknowledgements: None

Keywords:
Transient Osteoporosis hip (TOH)
Pelvic Girdle Pain (PGP)
Severe pathology

Topics:
Education: clinical
Musculoskeletal: lower limb
Pelvic, sexual and reproductive health

Did this work require ethics approval? No

Reason: It was a case series in a clinical setting. Informed consent of the patient was taken.