Factors influencing the mid-term radiological and functional outcomes of 41 post-fracture bipolar radial head arthroplasty cases at a mean follow-up of 87 months.

INTRODUCTION: When treating comminuted radial head fractures that cannot be adequately fixed, the next option is arthroplasty (radial head replacement). We hypothesized that the radiological and functional outcomes of bipolar mobile cup radial head arthroplasty is not influenced by the length of follow-up but instead by the correct positioning of the implant intraoperatively and by the presence of associated bone or ligament injuries. PATIENTS AND METHODS: Between May 1998 and December 2016, 82 cases of radial head arthroplasty were performed at our hospital. The mean age of patients at the time of arthroplasty was 53 years (22-81). Ligament or bone injuries complicated the radial head fractures in 70% of patients. RESULTS: For the final assessment, 41 patients were reviewed and included in the statistical analysis with a mean of 82 months (12-228). The mean MEPS at the final assessment was 88.7 (61-100). There were 23 excellent, 9 good, 9 average and 0 poor results. The average DASH score was 18.7 (0-55). The average VAS for pain was 1.0 (0-5). Five patients (12%) required surgical revision, including one implant change. Our statistical analysis found no relationship between follow-up time and functional outcomes. The appearance of periprosthetic radiolucent lines was not affected by the length of follow-up. Associated bone or ligament injuries significantly increased the probability of periprosthetic radiolucent lines, humeroulnar joint degeneration and decentering of the implanted cup. Radiological evidence of a suspended implant was associated with significantly worse functional outcomes. CONCLUSION: This study confirms the long-term stability of the clinical outcomes of radial head arthroplasty. There was no relationship between worsening radiological appearance of the implant and the clinical outcomes. It is critical that this implant not be oversized or suspended, as this can trigger premature capitellar erosion and painful stiffness of the operated elbow. LEVEL OF EVIDENCE: IV; systematic retrospective analysis.

Are orthopedic surgeons exposed to excessive eye irradiation? A prospective study of lens irradiation in orthopedics and traumatology.

INTRODUCTION: Numerous studies in recent years highlighted an increased risk of pathologies related to ionizing radiation in caregivers. A new French decree was adopted on June 4, 2018, dividing by 7.5 the radiation dose authorized in the lens for exposed workers. HYPOTHESIS: The hypothesis of the present study was that ocular irradiation in orthopedic surgeons was below the new legal threshold. METHOD: The equivalent dose (mSv) received by the lens was prospectively assessed in 10 orthopedic surgeons (5 senior, 5 residents), using 3 passive dosimeters placed at the forehead and either temple. Each intervention of each operator was recorded, with dose per area in the operating room at each use of the fluoroscope. RESULTS: All equivalent doses to the lens at the end of the 4 month study period were well below threshold. Doses were not significantly different between forehead and either temple (p=0.7, p=0.6 for the 2 temples). There was no difference according to side of the head (p=0.3). The dose received in the lens correlated with the dose delivered in the room (p=0.004). There were no significant differences in irradiation according to the surgeon's experience (p=0.2) or trauma activity rate (p=0.4). DISCUSSION: No studies have reported equivalent doses to the lens exceeding the authorized limit. But none previously measured equivalent dose to the lens according to the axis of irradiation in the eyes. The present study showed that orthopedic surgeons received as much eye radiation laterally as frontally. Ocular radiation protection needs therefore to be as effective laterally as frontally. The surgeon's experience did not emerge as a protective factor against ocular irradiation.