Reliability Analysis Of Radiological And Intra-operative Loosening In Total Elbow Arthroplasty

• Published in: Journal of shoulder and elbow surgery 2021-04
• Main Authors: Gandhi, Maulik J, Eyre-Brook, Alistair I, Gopinath, Praveen, Jones, Val, Booker, Simon J, Thyagarajan, David S, Ali, Amjid A
• Format: Article
• Language: English
• ISSN: 1532-6500

Revision of Total Elbow Arthroplasties (TEA) are commonly performed due to prosthetic loosening. National Joint Registry (NJR) data shows TEA revisions are becoming increasingly common with 123 TEA revisions performed in 2018 and 76 the previous year. TEA radiological assessment is based on subjective interpretation with no published criteria. We defined TEA loosening by the presence of at least one of the following criteria:1. Progressive widening of bone-cement, bone-prosthesis or cement-prosthesis interface 2. Fragmentation or fracture of cement 3. Prosthetic component migration 4. Bead shedding in porous coated prostheses. Using this definition, we looked at inter-observer and intra-observer agreement of radiological loosening and compared this assessment with intra-operative findings. In our tertiary center we conducted a retrospective review to identify TEA revisions performed between November 2008 and July 2018. Radiological implant loosening was independently assessed by 5 orthopedic surgeons. Inter-observer agreement (kappa coefficient) was calculated. The majority's view of radiological loosening was compared with intra-operative findings. Ninety-three sets of radiographs were identified with implant stability clearly documented in their operation note. Kappa coefficient between assessors for humeral implant loosening was 0.87 (almost perfect). Kappa coefficient for ulna loosening was 0.75 (substantial). Kappa coefficient for radiological and intra-operative findings for humeral loosening and ulna loosening were 0.67 and 0.71, respectively (substantial). Intra-observer reliability for humeral loosening was almost perfect ( = 0.86) and substantial for ulna loosening ( = 0.74). Our definition of loosening provides a reproducible inter-observer and intra-observer agreement of radiographic component loosening. In our center's experience, radiological findings may not translate to intra-operative findings and we would advise surgical strategies for TEA revision should include the possibility of needing to perform a dual implant exchange.