FAI may cause pain or functional impairment for an individual, as well as potentially resulting in arthritis and degeneration of the hip joint. Results from recent randomised control trials demonstrate the superiority of surgery over physiotherapy in patients with FAI. However, there is paucity of evidence regarding which factors influence outcomes for FAI surgery, most notably on patient reported outcomes measures (PROMs).

Our study looks to explore factors influencing the outcomes for patients undergoing surgery for FAI utilising data from the Non-Arthroplasty Hip Registry.

This study is a retrospective analysis of data collected prospectively via the NAHR database. Patients meeting the inclusion criteria, who underwent surgery between January 2011 and September 2019 were identified and included in the study. Follow-up data was captured in September 2020 to allow a minimum of 12 months follow-up.

Patients consenting to data collection received questionnaires to determine EQ-5D Index and iHOT-12 scores preoperatively and at 6 months, 1, 2- and 5-year follow-up.

Changes in outcome scores were analysed for all patients and sub-analysis was performed looking at the influence of; FAI morphological subtype, age, and sex, on outcome scores.

Our cohort included 4,963 patients who underwent arthroscopic treatment for FAI. There was significant improvement from pre-operative PROMs when compared with those at 6 and 12 months.

Pre-operatively, and at 12-month follow-up, iHOT-12 scores were significantly better for the cam / mixed groups compared to the pincer group (p<0.01).

In multivariable regression analysis, pincer pathology and a high-grade chondral lesion were associated significantly poorer iHOT-12 improvement at 6 and 12 months (p<0.05)

Age (<40 vs >40) demonstrated no statistical significance when considering 12 months outcome scores.

This study demonstrates that hip arthroscopy is an effective treatment for patients with symptomatic FAI and shows statistically significant improvements at 12 months.

The findings of this study are relevant to orthopaedic surgeons who manage young adults with hip pathology. This will help them to; predict which patients may benefit from operative intervention, and better inform patients, when undertaking shared decision making.

Pelvic re-orientation osteotomy is a well-recognised treatment of young adults with developmental dysplasia of the hip (DDH).

The most commonly used technique is the periacetabular osteotomy (PAO), however, some surgeons favour a triple osteotomy. These techniques can also be utilised for acetabular retroversion leading to FAI.

Despite the published literature on these techniques, the authors note a scarcity of evidence looking at patient reported outcome measures (PROMs) for these procedures.

This was a retrospective analysis of prospectively collected data utilising the UK NAHR. All patients who underwent pelvic osteotomy from January 2012 to November 2019 were identified from the NAHR database. Patients who consented to data collection received EQ-5D index and iHOT-12 questionnaires, with scores being collected pre-operatively and at 6, 12 and 24 months post-operatively.

Nine hundred and eleven (911) patients were identified with twenty-seven (27) undergoing a triple osteotomy, the remaining patients underwent PAO. Mean age was 30.6 (15–56) years and 90% of patients were female. Seventy-nine (79) (8.7%) of patients had the procedure for acetabular retroversion leading to FAI

Statistical analysis, of all patients, showed significant improvement (p<0.001) for; iHOT-12 scores (+28 at 6-months, +33.8 at 12-months and +29.9 at 24-months)

Similarly there was significant improvement (p<0.001) in EQ-5D index (+0.172 at 6-months, +0.187 at 12-months and +0.166 at 24-months)

Pre-operatively, and at each follow-up time-period, raw scores were significantly better in the DDH group compared to the FAI group (p<0.05); however, the improvement in scores was similar for both groups.

For both scoring measures, univariable and multivariable linear regression showed poorer pre-operative scores to be strongly significant predictors of greater post-operative improvement at 6 and 12 months (p<0.0001).

Hip arthroscopy is performed in a number of specialist centres throughout the UK with good results, no work has been published on the outcomes of hip arthroscopy in the District General Hospital setting. The early results from our prospective observational study show good outcomes in patients with femoro-acetabular impingement (FAI) and labral pathologies. To date we have follow-up data on 46 patients who have undergone hip arthroscopy with a mean follow-up period of 23 weeks. Of these patients 14 were male (30%) and 32 were female (70%) with a mean age of 36 years (16 to 62). Analysis of the data has shown a mean improvement in the Modified Harris Hip Score from 46.89 pre-operatively to 59.50 post-operatively (p<0.01) and a mean improvement in the Non-arthritic Hip Score from 47.38 pre-operatively to 66.74 post operatively (p<0.01). One of the patients has since undergone a total hip arthroplasty. There was one episode of minor wound infection treated successfully with oral antibiotics. There are been no cases of nerve injury or venous-thromboembolism. Our results demonstrate that hip arthroscopy can be provided safely in the DGH setting with good early functional outcomes.

Introduction: Dislocation remains one of the most common orthopaedic complications of hip replacement. Surgical technique, implant design and patient factors have been suggested as risk factors. The 2005 AOA Joint Registry recorded data on 101, 952 hip procedures between 1999 and 2004. We analyzed risk factors for early revision in this group of patients.

Methods: Ethics approval was obtained then a formal application was made to the Australian Joint Registry to release the required data. All primary hip replacements between 1/09/1999 – 31/12/2004 were studied. Statistical analyses of traditional risk factors including initial diagnosis, sex, age and head size were performed. We also studied the effect of fixation method on revision for dislocation.

Results: A total of 65,992 primary hip replacements across all diagnoses groups recorded were investigated with regard to diagnosis. The only initial diagnoses with significantly increased relative risk (RR) of revision for dislocation compared to osteoarthritis was fractured neck of femur (RR 2.25, p< 0.0001) and rheumatoid arthritis (RR 1.9, p< 0.01).

58,109 primary hip replacements for osteoarthritis were investigated for effect of age group, sex and fixation method. Age group and sex were not significant risk factors in revision for dislocation. Studying fixation method, cementless acetabular components were implanted more frequently (49,027, 84%) than cemented (9,082, 15.6%). In total, there were 428 (0.7%) revisions for dislocation, 369(0.8%) with a cementless acetabulum and 59 (0.6%) with cemented. Relative risk (cementless v cemented acetabulum adjusted for age group, sex and head size) of 1.59 (CI 1.19 to 2.12, p< 0.01). Head sizes of > 30mm, 28mm, 26mm and 22mm had significantly increasing relative risk (p< 0.001).

Discussion: The results from this large database indicate rheumatoid patients and those after fractured neck of femur have increased risk of revision for dislocation compared to osteoarthritis. Many of the traditional groups thought to be at higher risk of dislocation were not associated with an increased risk of revision for dislocation. These included age group, sex, avascular necrosis, developmental dysplasia and failed internal fixation. Cementless acetabuli have a higher rate of revision for dislocation. This has not been previously reported. Further investigation is needed to identify the cause of this finding.

32 consecutive patients who suffered open [Gustilo grade IIIB] distal tibial [AO type 43B and C] ‘Pilon’ fractures were prospectively studied in order to assess long-term functional outcome. All patients had radical debridement with immediate [within 24hrs] skeletal stabilisation and early soft tissue cover with a vascularized muscle flap as per our hospital’s protocol for management of severe open tibial fractures. The minimum follow-up was one year [range 1–8 years]. The superficial infection rate was 13% [4/32], deep infection rate was 6% [2/32] and the amputation rate as 6% [2/32]. There were no long-term problems with union and none of the patients required an ankle fusion. Patients were assessed using the SF-36 questionnaire. There were sig-nificant differences from the US norm in physical function score [p< 0.01], role physical score (p< 0.05) and physical component score (p< 0.01). Physical component score of 38.5 was significantly better (p< 0.01) when compared with amputees from severe lower extremity trauma. Our protocol for management of severe open pilon fractures resulted in a good functional outcome with low infection and amputation rates.

Introduction: Aseptic loosening is a long-term complication of many cemented arthroplasty procedures. The integrity of the fixation interface, in particular the level of interdigitation between cement and bone, is crucial to sustaining the stability of arthroplasty components[1]. Studies have shown that the viscosity of cement at the time of application is a significant parameter in determining this level of interdigitation[2]. However, the rheological properties of cement at key stages in arthroplasty procedures have not been quantified, and it is unclear if current operative techniques achieve optimum cement delivery properties. Furthermore, because the cure process of bone cement is highly dependent on environmental conditions, it is extremely difficult to accurately predict the time to curing. Oscillatory shear rheometry can be used to characterise the viscoelastic properties of bone cement. However, most commercial rheometers used for this purpose are too large, expensive and delicate for peri-operative use. The aim of this work is to develop a new laboratory method for measuring the viscoelastic properties of bone cement at the time of application and to investigate the relationship between these properties and the level of cement interdigitation.

Methods: A simple, inexpensive electromagnetic rotary actuator has been developed to provide accurate measurements of force, displacement and velocity without the use of sensors. These parameters can be used to continually monitor both viscous and elastic properties of curing bone cement. To consider subjective cementation techniques, a method has been devised where a surgeon indicates early and late doughing stages for a PMMA bone cement within a clinical environment. A computer interface has been developed to plot the real-time properties of the cement that are measured using the self-sensing device concurrently. The range of practical variability of cement delivery properties is then established. In order to investigate the effect of cement viscosity on the level of interdigitation a rig has been developed in which cement is applied to a standardised bone analogue under controlled conditions. The open pore ceramic analogue has been shown through microCT scanning to have a structure that is representative of the trabecular structure in human bone. CMC solution is used to represent back bleeding. Once set, the sample is evaluated using microCT to measure the level of interdigitation.

Results: Preliminary results show that bone cement has largely viscous properties following mixing and largely elastic properties towards setting. Values of dynamic viscosity obtained show the cement to have a low viscosity following mixing, then as polymer beads begin to dissolve in the monomer, the viscosity rapidly increases. The rate of viscosity increase then slows as polymer chains are created, before a final rapid increase in viscosity indicating the onset of setting.

Conclusion: A validated method has been developed to measure the viscoelastic properties of curing bone cement at key stages in arthroplasty procedures and to investigate the effect of these viscoelastic properties using a simple standardised bone model.

The purpose of this study was to assess if the use of sterile stockings in lower limb surgery results in the contamination of the operative site with skin commensals from unprepared skin.

Twenty-five consecutive patients under going elective single knee arthroscopy were included in our study. All patients were operated on in the same laminar airflow theatre, by the same surgeon using the same method of skin preparation and operative technique.

Skin swabs were taken from each patient’s foot prior to the commencement of surgery. The limb was then prepared as follows;

An unscrubbed assistant holds up the leg, the leg is then prepared with betadine, by the surgeon from ankle to thigh, sparing the foot.

Two samples were also cut from the cuff of the stocking, one prior to its use to act as a control and the other once it had been unrolled up the leg. The three samples were then sent to microbiology. The swabs were plated out on blood (x2), chocolate and Maconkey agar. One blood plate was incubated anaerobically at 37°c and the others in air at the same temperature. The stocking sample was cultured in nutrient broth. After 48 hours isolates were identified using standard techniques.

The results showed that none of the stocking samples yielded positive microbiology, however all of the foot swab samples did. They all grew coagulase negative Staphylococcus (CNS), five also grew conforms and one grew Pseudomonas, as well.

We can conclude from this, that this method of skin preparation using the sterile stocking is safe. It appears in this study, that the action of unrolling the stocking over the unprepared foot and then up the prepared leg does not contaminate the prepared operative site with commensals from the foot. However concern is raised by the high incidence of CNS on the foot, and may be a source of potential infection.