Ultrasound in the early diagnosis of heterotopic ossification in patients with spinal injuries

Abstract

Heterotopic ossification (HO) is a potentially disabling complication of spinal injuries and other chronic disorders. It is of unknown aetiology and currently there is no easy or convenient diagnostic method that will allow very early confirmation of the inflammatory changes that precede osteoid and, later, true bone formation. Clinical experience, however, indicates that early treatment with radiotherapy, antiinflammatory agents or diphosphonates is needed to control the progression.This study was undertaken to assess the role of ultrasound (US) in the very early diagnosis of HO in patients with spinal injuries.US was found to be very sensitive in detecting focal soft tissue abnormalities around joints and in the muscles of these patients. If combined with a Doppler study to exclude deep venous thrombosis (DVT), and infection or tumour could be excluded clinically, US was extremely accurate in predicting the presence or absence of early HO changes within hours of the clinical manifestation. In 2 patients it successfully predicted HO in the opposite leg before clinical signs were evident.This study also provided supportive evidence of the theory of microtrauma in the aetiology of HO.As ultrasound is portable, safe, cheap, reproducible and accurate, it is the method of choice in the early diagnosis of HO. It allows early treatment to prevent the formation of osteoid and subsequent bone formation.

Microvascular changes in the lower extremities of paraplegics with heterotopic ossification

“…16 In addition, a lymphatic microangiopathy of paretic legs was detected by¯uorescence microlymphography 17 and by morphological investigations. 10 Dilatation of lymph and blood vessels indicate functional changes probably related to immobilization and bed rest and they are probably the result of vascular adaptation to inactivity and skeletal muscle atrophy.…”

“…10 Dilatation of lymph and blood vessels indicate functional changes probably related to immobilization and bed rest and they are probably the result of vascular adaptation to inactivity and skeletal muscle atrophy. 9,16 The microvascular changes are most evident in those subjects with thromboembolic disease. In these patients the venous out¯ow obstruction caused by deep venous thrombosis accompanied by the absence of the ambulatory venous pressure in the paretic leg, determines skin microvascular dilatation and consequent transcapillary di usion of plasma and lymph material into the perivascular connective tissues.…”

Neurogenic heterotopic ossification in spinal cord injury

“…16 Ultrasonography can be used for the early identi®cation of clinically suspected NHO and for di erentiating NHO from DVT, a developing pressure sore, infection, or tumor. 60,65,69,112,119 The use of phlebography to di erentiate between NHO and DVT can be misleading. A large mass of ectopic bone can distort and compress vascular structures, causing venographic ®ndings that mimic venous thrombosis.…”

“…Serial sonography allows di erentiation from muscle tears, soft tissue haematoma, abscess, thrombosis and soft tissue tumor. 67,68,119,135,136 Sonography has the advantage of the possibility of bedside application, is relatively cheap, and requires no radiation.…”

Prolonged fever and heterotopic ossification in a C4 tetraplegic patient. Case report

“…16 More recently, ultrasound has also been found to be useful especially in situations where deep vein thrombosis is a differential diagnosis. 17 Apart from the use of disodium etidronate in the treatment of established HO, careful regular stretching of involved joints to maintain range of motion is also important. Although controversial, repeated forceful manipulation of joints has also been advocated.…”