Nicholas D Peterson, David Metcalfe, JM Wilkinson, Daniel Perry

Background: In this study, we aimed to describe temporal trends and survivorship of total hip arthroplasty (THA) procedures in very young patients (aged ≤20 years).

Methods: A descriptive observational study was undertaken using data from the National Joint Registry (NJR) for England, Wales, Northern Ireland and the Isle of Man. All patients aged ≤20 years at the time of undergoing primary THA were included and the primary outcome was revision surgery. Descriptive statistics were used to summarise the data and Kaplan-Meier estimates calculated for cumulative implant survival.

Results: There were 769 arthroplasty procedures performed in 703 patients. Seven patients died and 35 THAs were revised during the follow-up period. Uncemented implants and ceramic-on-ceramic (CoC) bearing surfaces were most commonly used. The use of metal-on-metal (MoM) bearings and resurfacing procedures declined from 2008. The most frequently recorded indications for revision were loosening (20%) and infection (20%), although the absolute risk of these events occurring within the cohort was low at 0.9%. Factors associated with lower THA survival were MoM and metal-on-polyethylene (MoP) bearings and resurfacing arthroplasty (versus ceramic-on-polyethylene [CoP] and CoC bearings, p=0.002), and operations performed by surgeons with a lower frequency of very young patient THAs recorded in the NJR (versus those with >5 recorded operations, p=0.030). Kaplan-Meier estimates suggested 96.2% (95% confidence interval [CI] 94.2-97.6%) survivorship of implants across the cohort at 5 years.

Conclusion: Within the NJR, the overall survival for very young patients undergoing THA exceeded 96% over the subsequent five years. Surgeons should consider the increased risk of early revision with implant type, volume of young hip arthroplasties performed and bearing surface when performing THA in children and young adults.

T. Ankers, N. Donnachie

Background: Periprosthetic joint infection (PJI) is a devastating complication of hip and knee arthroplasty. I have encountered a variety of strategies for skin preparation during my training. In this abstract a review of current literature regarding pre-operative skin preparation is summarised. A protocol based on the evidence is proposed.

Methods: A literature search was performed using Medline and EMBASE. It focussed on five aspects of skin preparation: MSSA & MRSA screening, pre-operative washing, hair removal, skin disinfection and incise drapes.

Findings: Evidence suggests that screening for MSSA and subsequent eradication reduces the rate of PJI. This intervention has been shown to be cost effective. There is recent evidence to support pre-operative washing with chlorhexidine gluconate (CHG) impregnated cloths. There is limited evidence to support the routine removal of hair from the operative site. If hair must be removed, clippers or depilatory cream are preferable to a razor. Regarding skin disinfection, a CHG and alcohol mixture may be more effective than iodophors. A second application of disinfectant, prior to placing the incise drape, has been shown to reduce infection rate. Lastly incise drapes themselves have not been shown to reduce the rate of infection. Those incise drapes not impregnated with iodine may increase infection rates.

Conclusion: Based on the findings of this literature review I propose the following skin preparation regime for patients undergoing hip and knee arthroplasty:

1. MSSA and MRSA screening in all patients and eradication in carriers.
2. Pre-operative washing with CHG cloths the night before and morning of surgery.
3. Hair removal with clippers if required.
4. Skin disinfection with a CHG-alcohol scrub before draping and again before applying the incise drape.
5. Iodine impregnated incision drapes.

Mohammed As-Sultany, Janice Armour, Jennifer Bowden, Rosemary Finley, Nigel J Donnachie

Background: Deciding when to safely operate on hip fracture patients taking DOACs is a challenge. The aim of this unique audit was to assess the safety of a new local guideline implemented in a busy district general hospital.

Methods: A retrospective review of all hip fracture patients taking DOACs during 2016 (Group 1) was carried out. Following presentation of the results, the new local guideline was introduced in August 2017. The recommended timing of surgery for each patient was based on the type of DOAC taken, the time of the last dose and the creatinine clearance on admission. A prospective audit following the implementation of the guideline was carried out between August 2017 and May 2018 (Group 2). Statistical analysis comparing both groups was carried out using the Student’s t-test and Fisher’s exact test, with a p-value of <0.05 indicating statistical significance.

Results: There were 33 patients in Group 1 and 48 patients in Group 2. They shared similar demographic data with the commonest DOAC being Apixaban taken mainly for atrial fibrillation. Group 2 showed that there was an 82% increase (p = 0.02) in the number of patients having surgery within the recommended best-tariff practice (BTP) of 36hrs. There was no statistical difference found in the amount of post-operative haemoglobin concentration drop (p=0.34) or the number of post-operative RBC transfusions (p=0.16) between the two groups. There was no increase risk in the number of re-operations due to wound problems or infections. There was no increase in mortality at 30 days (p=0.64), 3 months (p=0.34) or 1 year (p=1). The average total length of inpatient stay was comparable between the two groups (p=0.42).

Conclusions: Early results of this new guideline have shown that hip fracture patients taking DOACs could safely have surgery within the recommended timeframe.

Robert J MacFarlane, Ignatius Liew ,James Widnall , Andrew Molloy , Lyndon Mason

Background: Lisfranc ligament complex injuries are uncommon and frequently associated with high energy trauma. Dorsal bridge-plating has gained popularity in recent years as an alternative to transarticular screw fixation of the TMTJ’s. We present clinical outcomes and complications for dorsal bridge plating of Lisfranc fracture subluxations in a series of patients at our institution.

Methods: A retrospective casenote and radiographic review of all cases with Lisfranc injuries presenting to a major trauma centre in a 5 year period. Follow up was at 2 weeks, for wound review and plaster change, then 6 and 12 weeks, and every 6 months. Clinical outcomes using Manchester-Oxford foot&ankle questionnaire, EQ-5D and VAS pain scores were obtained.

Results: There were 18 male and 12 female patients. Male:female ratio was 3:2. The mean age was 41 years (range 16-70). Mean total follow up time was 336 days (range 50 to 1269 days). Mean length of follow up was 47 weeks (range 7 -147). Mean time to surgery was 11 days (range 0-24). 23% of patients were admitted as a major trauma activation. Mean time to union was 8 weeks (range 6-12). 9 required removal of hardware, 2 required injections, and 2 required fusion. There 6 complications, including CRPS (1 case), and persistent pain in 5 cases. 12/19 cases returned to work (63%) at a mean time of 28 weeks (range 18-60). The mean final MOXFQ sore was 33.5 (range 21.2-39.6). Mean final VAS pain score was 5.5 (range 1-8).

Conclusions: Previous studies have reported the results of several different surgical treatment methods, principally including primary arthrodesis and internal fixation. The present study compares favourably with recent reports for dorsal plating of TMTJ.

Implications: This study provides useful evidence for the use of dorsal bridge plating in complex midfoot injuries associated with high energy trauma.

Jayatilaka L, Swanton E, Fisher A, Fisher L, Fischer B, Molloy A , Mason L

Background: The anatomy of the the lateral tarsometatarsal ligamentous structures are under investigated. A number of classifications have previously been proposed, noting homolateral and divergent subtypes of midfoot fracture dislocations. These subtypes indicate intact metatarsal connections of the middle and lateral rays, however little is understood in regards to these connections. There are currently no anatomical studies analysing the middle to lateral plantar ligamentous insertions. Our aim was to identify the plantar ligamentous structures of the lateral tarsometatarsal joints and their significance in tarso-metatarsal joint injuries.

Methods: We examined 10 cadaveric lower limbs that had been preserved for dissection at the Human Anatomy and Resource Centre at Liverpool University. The lower limbs were dissected to identify the plantar aspect of the transverse metatarsal arch.

Results: In all specimens, the short plantar ligament blended with a transverse metatarsal ligament (lateral Lisfranc) spanning from the 2^nd to the 5^th metatarsal. The separate short plantar ligament formed the floor of the peroneus longus canal. The transverse metatarsal ligament formed the basis of the roof and distal aspect of the peroneus longus canal. In addition, separate intermetatarsal ligaments were identifiable connecting each metatarsal. The short plantar ligament provides connection through the transverse metatarsal ligament, connecting the transverse and longitudinal arches of the foot.

Conclusion: The plantar ligamentous structures of the lateral tarsometatarsal joints are a combination of individual intermetatarsal ligaments and a transverse metatarsal ligament (Lateral Lisfranc). This explains the homogenous nature of a divergent tarsometatarsal joint injury and why middle and lateral columns move as one. The lateral Lisfranc ligament acts like a suspension bridge, storing energy during stance phase that could be released during propulsive phase. This study has clinical significance in the observation that in some cases lateral column instability can be overcome when the middle column is stabilised.