Results of Arthroplasty for Avascular Necrosis of the Humeral Head in Sickle Cell Patients.

Abstract

Avascular necrosis (AVN) of the humeral head is a debilitating complication of sickle cell disease (SCD) estimated to occur in ~5% of patients for which the optimal therapy is not well defined. Although shoulder replacement is often used for AVN in other settings, little information is available about the outcome of shoulder arthroplasty in this population. In this study, medical records, radiographs, and pre-operative assessment scores of eight adult patients with sickle cell disease were reviewed. Post-operative assessment scores and radiographs were prospectively collected by an independent observer at follow-up appointments. All eight patients had >2 years of follow up. The mean age of the patients at the time of surgery was 37 years old and there were 4 males and 4 females. Six of the patients had Hgb SS, one had Hgb SC and one had Hgb Sβ+ thalassemia. The average duration of symptoms prior to surgery was 26 months. Based on pre-operative shoulder radiographs, 5 of 7 evaluable patients had grade 3 or greater disease. Seven of eight patients had a hemiarthroplasty and one patient had a total arthroplasty. The mean follow up was 51 months. Complications included two episodes of sickle cell crises in the immediate post-operative period, and one intraoperative rotator cuff tear. One patient developed stiffness that required arthroscopic capsular release 22 months after his initial surgery. No infections were seen in the operated shoulder and no shoulder revisions were performed. At the most recent follow-up, the average American Shoulder and Elbow Society (ASES) score improved 31 points, indicating substantial functional improvement (J Shoulder Elbow Surg . 3(6):347–352, 1994). However, only 25% of the patients reported improvement in pain as assessed by a visual analog scale. While two patients had dramatic improvements in all aspects of our outcome measures, two other patients had decreased functional capacity with no improvement in pain. Radiographs at the most recent follow up revealed slight loosening of the prosthetic stem in one patient but no other radiographic complications. In conclusion, shoulder arthroplasty provides improvements in range of motion and joint function in the majority of patients. However, pain relief is less predictable, suggesting that other causes of sickle cell related pain are occuring. Nevertheless, given the limited options available for the treatment of AVN in sickle cell patients who have failed conservative approaches, shoulder arthroplasty is a reasonable treatment option.