Atraumatic osteonecrosis of the humeral head after influenza A-(H1N1) v-2009 vaccination

In the recent pandemic influenza A-(H1N1) v-2009 vaccination campaign, adjuvanted vaccines have been used because of their antigen-sparing effect. According to available reports, the rate of severe vaccination reactions has not increased, as compared with previous seasonal influenza vaccinations. Here we describe an adult female patient who was vaccinated with an AS03 adjuvanted split-virus vaccine injected into the left arm. She experienced a prolonged and painful local reaction for 4 weeks. During this time, persistent incapacitating pain shifted into the left shoulder. Magnetic resonance imaging (MRI) at the injection site detected atraumatic humeral head osteonecrosis in conjunction with bursitis of the rotator cuff region. Clinical and laboratory examination revealed no other underlying disease. Using analgetic medication and physical therapy, resting pain completely remitted within the following 14 weeks. Pain on exertion declined within the following 6 months. Atraumatic osteonecrosis, a relatively rare disorder which initially presents non-specific clinical symptoms, has never been associated with parenteral influenza vaccination. Although the available data cannot establish a causal relationship, our patient's clinical course - with a continuous transition from increased local post-vaccination reactions to symptoms of a severe shoulder lesion with osteonecrosis - raises the question of a pathogenetic link. Considering the vascular pathogenesis of osteonecrosis, we hypothesize that our patient's enhanced local immunologic reaction may have led to regional vasculitis as the cause of bone destruction. As mild forms of osteonecrosis may have escaped previous clinical attention, it is the purpose of our report to increase awareness of this exceptional event as a possible side effect of parenteral adjuvanted vaccination.

Resektion der infizierten Achillessehne

BACKGROUND

Structural full-thickness defects of the Achilles tendon represent a severely disabling injury which should be treated by reconstruction. This study presents functional outcomes from standardised follow-up of non-reconstructed Achilles tendons with soft tissue coverage alone.

PATIENTS AND METHODS

Seven patients were treated with various techniques of soft tissue reconstruction without restoration of the Achilles tendon. After a mean of 11 months postoperatively, the lower extremity was evaluated generally with regard to function, AOFAS score (ankle and hindfoot), and isokinetic torque testing by the Biodex system.

RESULTS

All patients showed high mobility, muscle strength, and range of motion at follow-up. The average AOFAS score was 84.7 (maximum 100), and the torque loss in plantar flexion was 44.5% on average compared to the uninvolved side and thus comparable with results after secondary tendon reconstruction.

CONCLUSION

After complete loss of the Achilles tendon, compensatory techniques can hinder significant loss of torque and endurance, compared with secondary tendon reconstruction, allowing unsupported mobility and even top athletic performance.