Idiopathic fibrosis of the quadriceps muscle: a case report with magnetic resonance imaging and pathological findings.

BACKGROUND: Idiopathic fibrosis of the quadriceps muscle can be defined as progressive loss of knee flexion due to fibrosis within the muscle developed in early childhood. A few cases have been reported, but these did not detail the MRI and pathological findings. MATERIAL AND METHOD: A 28-year-old woman presented with difficulty in sitting and inability to bend both knees completely. The clinical evaluation, radiological examination, MRI, treatment and muscle pathology were demonstrated RESULTS: The knee flexions were limited in both knee joints. Magnetic resonance imaging of both thighs showed marked quadriceps muscle atrophy with fat infiltration and fibrous band. Intraoperative findings demonstrated fibrous band of vastus intermedius and vastus lateralis muscles which correlated with the MRI. The histological findings also revealed loose connective tissue separating muscle fibers and large fibrous band Z-plasty and release of the fibrotic muscles were performed. The result of the surgery was good CONCLUSION: This is the first report to correlate MRI and pathological findings of idiopathic fibrosis of the quadriceps muscle. Late diagnosis and treatment may produce irreversible changes of femoral condyles and patella. Clinical awareness with history, physical examination and radiographic findings which included MRI help in confirming the diagnosis and demonstrating the extent of fibrosis before surgery.

Electromyographic activities during isometric contraction of interphalangeal joint extensors of the finger.

OBJECTIVE: To investigate which hand muscles were used for interphalangeal joint (IP) extension when holding the metacarpophalangeal joint (MCP) in 90 degrees flexion, 0 degrees, and full hyperextension. MATERIAL AND METHOD: Fifteen volunteers extended IP when MCP was manually maintained in 90 degrees flexion, 0 degrees, and full hyperextension for 5 seconds with and without maximal manual resistance twice each. Maximal resistance was ensured and maintained manually by the actions of both researcher and subject. By using needle electromyography, the root mean square (RMS) * values representing the muscle function of the extensor digitorum communis (EDC), lumbrical, and interosseous muscles of the middle fingers of the dominant hands were recorded and averaged from the two tests conducted on each subject. RESULTS: In 87% of the subjects, EDC had the highest RMS value in 90 degrees MCP flexion without resistance, and in 100% of them, it had the highest value in both 90 degrees MCP flexion and 0 degrees with resistance. There were no clear differences between the three muscles when extended in all other positions. When the same muscles were compared, it was found that EDC had the highest value in 90 degrees MCP flexion, especially without resistance. Its RMS values were significantly increased when the resistance was applied in all positions. It was also found that the lumbrical and interosseous muscles had the highest RMS values in full hyperextension. CONCLUSION: EDC had the highest muscle activity for IP extension in 90 degress MCP flexion, especially when the resistance was applied. However, the activities among the three muscles could not be clearly differentiated when extended in other positions.