The aim of this modified Delphi process was to create a structured Revision Hip Complexity Classification (RHCC) which can be used as a tool to help direct multidisciplinary team (MDT) discussions of complex cases in local or regional revision networks. The RHCC was developed with the help of a steering group and an invitation through the British Hip Society (BHS) to members to apply, forming an expert panel of 35. We ran a mixed-method modified Delphi process (three rounds of questionnaires and one virtual meeting). Round 1 consisted of identifying the factors that govern the decision-making and complexities, with weighting given to factors considered most important by experts. Participants were asked to identify classification systems where relevant. Rounds 2 and 3 focused on grouping each factor into H1, H2, or H3, creating a hierarchy of complexity. This was followed by a virtual meeting in an attempt to achieve consensus on the factors which had not achieved consensus in preceding rounds.Aims
Methods
Orthopaedic surgical hoods rely on an intrinsic fan to force clean external air over the wearer and allow potentially contaminated and expired air to flow down and away from the surgical field. Carbon dioxide (CO2) is produced through aerobic metabolism and can potentially accumulate inside the hood. Levels above 2500ppm have been shown to affect cognitive and practical function in flight simulator studies. Maximum Health and Safety Executive (HSE) 8-hour exposure limit is 5000ppm There is a paucity of data on real-world CO2 levels experienced during arthroplasty surgery whilst wearing a hood. CO2 levels were continuously recorded during 31 elective arthroplasties, both primary and revision. Data was collected for surgeon and assistant. Data was recorded at 0.5Hz throughout the procedure utilising a Bluetooth CO2 detector, worn inside a Stryker Flyte™ surgical helmet worn with a toga gown. Four surgeons contributed real time data to the study. This data was augmented with experimental data, investigating varying fan speeds and activity levels. Median operative duration was 82 minutes (range 36–207). The average CO2 level across all procedures was 2952ppm, with 22 of the cases having a mean above 2500ppm, but none having a mean above 5000ppm. For each procedure, the time spent above 2500 and 5000 ppm was calculated, with the average being 68.4 % and 5.6% respectively. The experimental data demonstrated higher CO2 levels with lower fan speed, and at higher activity levels, and levels exceeding 15000 ppm during gentle exercise. During operative cases, low fan speed cases did have a marginally higher mean CO2 value than high fan speed (3033.02 and 2903.56 respectively) but the small numbers of cases (n=10) where this data was captured limit the relevance of this difference. The use of surgical helmets for elective orthopaedic surgery, can results in CO2 levels regularly rising to a point which may affect cognitive function. This study recommends the use of a higher fan speed where possible to minimise the risk of such CO2 levels, and recommends further research in this area.
Trabecular metal (TM) augments are designed to support an uncemented socket in revision surgery when adequate rim fit is not possible. We have used TM augments in an alternative arrangement, to contain segmental defects to facilitate impaction bone grafting (IBG) and cementation of a cemented socket. However, there is a paucity of literature supporting the use of this technique. We present one of the largest studies to date, reporting early outcomes of patients from a tertiary centre. A single-centre retrospective analytical study of prospectively collected data was performed on patients who had undergone complex acetabular reconstruction using TM augments, IBG and a cemented cup. All patients operated between 2015 and 2019 were included. We identified 105 patients with a mean age of 74yrs. The mean follow-up was 2.3 years(1–5.5yrs). Our primary outcome measure was all-cause revision of the construct. The secondary outcome measures were, Oxford hip score (OHS), radiographic evidence of cup migration/loosening and post-op complications. Eighty-four out of 105 patients belonged to Paprosky grade IIb, IIc or IIIa. Kaplan-Meier survivorship for all-cause revision was 96.36% (CI, 90.58–100.00) at 2 years with 3 failures. Two were due to early infection which required two-stage re-revision. The third was due to post-operative acetabular fracture which was then re-revised with TM augment, bone graft and large uncemented cup. Pre-op and post-op matched OHS scores were available for 60 hips(57%) with a mean improvement of 13 points. Radiographic analysis showed graft incorporation in all cases with no evidence of cup loosening. The mean vertical cup migration was 0.5mm (Range −5 to 7mm). No other complications were recorded. This study shows that reconstruction of large acetabular defects during revision THA using a combination of TM augments to contain the acetabulum along with IBG to preserve the bone stock and a cemented socket is a reliable and safe technique with low revision rates and satisfactory clinical and radiographic results. Long term studies are needed to assess the possibility of preservation and regeneration of bone stock.
