Andrew Yun

Daniel Estok

Dr. Andrew Yun retrospectively reviewed 24 patients with JRA who underwent 39 hemiarthroplasties. After an average 12 year follow-up, 14 hips were revised and 25 hips still had their original hardware. Harris hip scores done preop and at the time of follow-up for the study showed a mean improvement of 40 points. Osteolysis around the components was associated with bead shedding of the Osteonics HS2P prosthesis, accounting for 71% of failures requiring revision. Other factors that were found to be significant risks for failure included unilateral replacement and need for acetabular grafting.

Dr. Daniel Estok, in his discussion, noted the challenge in finding an optimal treatment for this very disabling and progressive disease. He discussed the frequent need for nonstandard implants and techniques, as well as the importance of preserving and hopefully restoring bone stock in these young patients. Dr. Estok also commented on the study ’s finding of progressive acetabular erosion and pointed out the need to closely follow these patients so that revision can be planned while there is still adequate bone stock to hold a hemispheric screw-fixed implant.

Greg Erens

Dennis Burke

Dr. Greg Erens presented a retrospective review of 63 consecutive patients who underwent revision total hip arthroplasty by a single surgeon. The average time to follow-up was 4. 2 years. The mean Harris hip score increased 34 points from preoperative evaluation. He disussed the complica- tions encountered, including 2 hips requiring revision of both components for recurrent dislocation, and a third requiring revision of the acetabular component only for recurrent dislocation. Dr. Erens found that radiographic evaluation showed stable fixation in all femoral components, with only one femur having evidence of osteolysis. He did a comparison with other published series of femoral revisions as well as a series of primary THA using the S-ROM and found this study ’s results to compare favorably with the literature in terms of rates of re-revision, mechanical failure, and osteolysis.

Dr. Dennis Burke discussed the history of revision hip arthroplasty, not- ing that cementless revision is the standard. He outlined the development of the S-ROM approximately 20 years ago, and how its 8000 combinations provide excellent versatility, particularly in revision surgery. He commended Dr. Erens on his work evaluating the intermediate-term outcomes of S-ROM for revision arthroplasty, but encouraged the investigators to also analyze the relationship of technique to the higher rate of dislocation in this series.

Kingsley Chin

Henry Mankin

Dr. Kingsley Chin reviewed the outcomes of 38 patients with persistent diffuse pigmented villonodular synovitis, who had undergone at least one previous arthroscopic synovectomy, and were then referred for open synovectomy +/- radiation due to ongoing symptoms. 57. 9% of the patients had undergone at least one additional procedure after their index synovectomy. 89. 5% of patients had noted improvement in symptoms after their synovectomy, but all found their symptoms at latest followup (mean 3. 6 years) worse than prior to the first synovectomy. Dr. Chin concluded that arthroscopic synovectomy may alleviate short-term symptoms but if it fails to eradicate DPVNS, it may delay more aggressive, definitive treatment. Longterm MRI followup was recommended to monitor staging of disease and assess results of arthroscopic synovectomy.

Dr. Henry Mankin served as discussor for this work, giving a historical perspective to the proposed etiologies and treatments of DPVNS. He raised the question as to whether radiation around the knee should be limited when the patient may likely require future surgery. He commented on the need for further research into the genetics of DPVNS, as well as into the outcomes of various treatment protocols, including the possibility of a prospective trial of open synovectomy vs open synovectomy with radiation.