"literature article entitled, ¿dislocation after polyethylene liner exchange in total hip arthroplasty¿ by henry r.Boucher, md, et al, published by the journal of arthroplasty (2003), vol.18, no.5, pp.654-657, was reviewed.The authors reviewed 24 patients from our clinic who had an isolated polyethylene liner exchange performed between november 1992 and march 2000 for wear or osteolysis with retention of the acetabular shell and femoral stem.Original implants were all depuy products.The 25 revisions of the index tha polyethylene liners are captured within this complaint.During the initial revision, 3 patients had head exchanges to accommodate the exchanged liner.The cups and stems were well-fixed and left in situ for all patients at initial revision surgery.Implanted products: the primary hip arthroplasties were performed with a posterolateral approach between 1983 and 1988.Twenty-four femoral components were aml stems (depuy, warsaw, in).One was a custom fully porous-coated stem (depuy).Twelve (50%) were monoblock femoral stems with 32-mm heads; 8 (33%) were modular 32-mm heads and 4 (17%) were 28-mm modular heads.Among the modular stems, neck length varied from short (0 to 2 mm) to medium (3 to 5 mm).The patients with monoblock stems had a nonmodular aml shell (depuy) with a neutral polyethylene geometry.The patients with modular stems had modular srom shells, of which 11 had 10° lipped liners and 1 had a 20° lipped liner.All lipped liners were oriented posteriorly.Cup diameters ranged from 46 to 63 mm.Results: 6 non-traumatic dislocations- 2 patients with 1 dislocation, 2 patients had 3 dislocations, and 1 patient with 5 dislocations.This patient¿s liner was re-revised 73.5 months after liner exchange and had a revision for a loose sup 81.5 months after liner exchange.The mean abduction angle for the 6 dislocations was 48 degrees.3 patients with dislocations had an aml monoblock stem.10 patients reported a decrease in joint mobility and 3 reported moderate to sever pain.Captured in this complaint: 6 heads and liners for dislocation- 1 revised.1 revision of cup for loosening.3 aml monoblock stems for dislocation.25 polyethylene liner exchanges for wear and/or osteolysis (initial revision surgery).3 femoral heads exchanged to accommodate new liner (initial revision surgery).Pain and medical device site joint movement impairment.The femoral stems were left in situ in all re-revision surgeries.This complaint captures.The initial revision surgery and all subsequent re-revision surgeries.".
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Product complaint # (b)(4).Investigation summary = > no device associated with this report was received for examination.A worldwide lot specific complaint database search, or device history record (dhr) review, was not possible because the required lot number was not provided.Based on previous investigations, this complication of joint replacement is unlikely to have been the result of a device failing to meet required specifications.The information received will be retained for potential series investigations if triggered by trend analysis, post market surveillance, or other events within the quality system.If information is obtained that was not available for the initial medwatch, a follow-up medwatch, a follow-up medwatch will be filed as appropriate.
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