Jump to comment:

• Why psoas abscess is ambiguous
  dr rajendra ravindra pol
  Published on: 31 August 2004

• Published on: 31 August 2004

  Why psoas abscess is ambiguous

  • dr rajendra ravindra pol, general medicine faculty
  • Other Contributors:
    • dr. rajendra pol

  Dear Editor

  Mallick et al have rightly pointed that it requires a high degree of clinical suspicion to diagnose these kind of abscesses.[1] The presentation with lower back pain, hip pain, lower abdominal pain and a limp is well known. A diligent physical examination is essential for the prompt diagnosis of this condition.

  One of the clinical presentation is femoral neuropathy. Femoral neuropathy is u...

  Show More

  Dear Editor

  Mallick et al have rightly pointed that it requires a high degree of clinical suspicion to diagnose these kind of abscesses.[1] The presentation with lower back pain, hip pain, lower abdominal pain and a limp is well known. A diligent physical examination is essential for the prompt diagnosis of this condition.

  One of the clinical presentation is femoral neuropathy. Femoral neuropathy is uncommon but a known presentation, even in the era when tuberculosis was common. This phenomenon is explained by the slow distension of psoas sheath and by the fact that the abscess ruptures through the psoas fascia before the femoral nerve could be damaged by the increased intrapsoas compartment pressure. Similarly acute non-tuberculous psoas infection rarely produces femoral nerve compression in case of psoas abscess, presumably because the psoas fascia is distensible. Femoral neuropathy however does occur with iliacus muscle abscess because the fascia iliaca is relatively indistensible.

  Apart from detecting psoas muscle weakness which is the usual presentation, it is also worthwhile to detect quadriceps weakness if at all it can be detected, because this muscle group is so strong that the examiners may not be able to detect the weakness. It may be sometimes evident from the history of the leg 'giving out' during walking or of the patient being unable to get out of a chair without using the arms. As the psoas muscle is innervated by L2, L3,L4, pain can radiate to the hip and thigh.

  Also detecting sensory loss not only over the anterior thigh, but also on the medial aspect of calf is useful. This loss has a saphenous nerve distribution (the terminal sensory branch of femoral nerve) the knee jerk is usually depressed. Hence it is of value to detect the above neurological signs in any patient presenting with nonspecific symptoms like lower back pain, flank pain, lower abdiminal pain,nonspecific pain in the hip and thigh and sometimes a limp.

  References

  1. Mallick I H, Thoufeeq M H, Rajendran T P. Iliopsoas abscesses. Postgraduate Medical Journal 2004;80:459-462.

  Show Less

  Conflict of Interest:
  None declared.

  • Back to top