Authors:
Connor Thorn, Jim Ballard, C Lockhart, Andrew Crone, Daniel Crawford, Alexander Aarvold 

University:
University of Southampton

Introduction:
3D models are an emerging tool for surgical planning, providing an augmented method for the visualisation of a patient’s anatomy. As their use increases, more data about the utility of these models is critical to inform budget allocation. This study provides the most comprehensive analysis to date for the use of 3D models in peri-operative management.

Methods:
3D models for complex surgical cases in NHS hospitals were delivered alongside a surgeon feedback survey. The survey on the model’s utility had been designed alongside the university data analytical team. This survey focussed on 5 areas: surgical planning and diagnosis, economic impact, impact on intraoperative and pre-operative time, effect on communication and direct impact on the patient.

Results:
There were 106 models used by 63 surgeons for complex surgical cases between May 2020 and March 2021, across multiple surgical specialities. Benefits were reported in all peri-operative areas, with 92.5% of responses agreeing the 3D model was a better method for diagnosis and planning than traditional 2D techniques. Benefits were reported on pre-operative planning (92.4%), economic savings due to equipment selection (54.4%), reduction in surgical time (41.5%) and surgeon to surgeon communication (92.6%).

Conclusions:
3D models were shown to have a wide range of benefits within a surgical setting. The reduction in surgical time could have the potential to help alleviate the surgical backlog created by the COVID-19 pandemic. With more widespread use and optimisation of costs the use of 3D models could become the standard for unusual and complex surgical cases.

Authors:
Ali Assaf, Khaled Al-Kharouf, Mohammed Amer, Douglas Dunlop

Hospital:
University Hospital Southampton

Introduction:
Fixation of Vancouver B Proximal Femoral Fractures (VBPFFs) around Cemented Taper Slip stems (CTSS) where the bone cement interface is intact, has shown reduced blood transfusions and reoperations, compared to revision arthroplasty. Whether fixation is appropriate for all VBPFFs or a more selective approach would help reduce risks of subsidence and loosening is still unknown.

Methods:
All VBPFFs in primary THR around CTSS at SGH were reviewed. Primary outcome was revision rate. There was a variety of secondary outcomes.

Results:
50 VBPFFs were included. Average follow-up time was 13months. Mean age at fracture was 79years, mean ASA 2.8, average LOS 24days, with 33% mortality at 5years.
Revision rate was 10%(5/50). Two revised for loosening and 3 for non-union and failure of metalwork. Subsidence rate was 48%. Subsidence was associated with negative symptoms (P<0.0001). Major subsidence, observed in 8 patients, equated to significant mobility reduction. No dislocations were observed. There was 1 chronic infection treated with suppressive antibiotics.
High spiral and metaphyseal split fractures had higher subsidence rate (100% and 68%respectively) compared to low spirals and short oblique (11% and 0%respectively). The average EBL was 414ml, with 5 patients requiring transfusions.

Conclusions:
Our revision rate and EBL Results are consistent with the available literature. The high rate of subsidence is alarming and might be more reflective of functional outcomes than revision rates. A more selective approach utilizing a morphology based classification can help reduce the incidence of subsidence and maintain the benefits of osteosynthesis only.

Authors:
Fransiska Guerreiro, Niall Flynn

Hospital:
Queen Alexandra Hospital

Introduction:
Novel uncemented metal backed patella is designed to achieve osseointegration into the implant, aiming for biological fixation. Despite the modern design, there are still concerns remaining regarding loosening based on previous older designs. We reviewed the outcome of the novel patella implant to look at the short-term outcome in our Total Knee Replacements.

Methods:
Internal database of 3 hospitals were reviewed for the outcome of patients with Cementless Metal-Backed Patella Implant. Patient demographics and revisions were identified.

Results:
409 cases of Metal Backed Patella were identified between 2016 to 2020. Two types of prosthesis were used; Stryker Triathlon and Stryker Modular Rotating Hinge. Demographics are as follows; Male 42%, Female 59%; Patient age range 37-98.
There were 2 cases of infection; 1 had 2 stage revision, the other settled with Debridement, Antibiotics and Implant Retention (DAIR). 3 Cases of Polyethylene insert change unrelated to infection. There are no cases of patella loosening to date.

Conclusion:
Our data currently shows excellent outcomes in terms of function and survivorship for this novel implant. We are optimistic that the implant can show excellent survivorship in the long term.

Authors:
Jack Pearce

Hospital:
University Hospital Southampton

Introduction:
Zimmer’s NexGen Knee was introduced in 1995 and further updated with ‘High Flex’ devices.
Initially noted in UHS in 2015, there appeared to be a significant proportion undergoing early failure.
Recently noticed exponential increase in failing NexGen’s with a common pattern: atraumatic aseptic medial tibial collapse. At time of revision surgery tibial base plate found to have completely de-bonded from cement.
We have undertaken a retrospective review of our primary total knee revisions since December 2019 to evaluate what percentage of our workload this has become and how early the implants are failing.

Methods:
Inclusion criteria: all elective first revisions of primary total knee replacements since 01/12/2019
The departments local revision knee database was used to identify all procedures since December 2019.
With each identified case their preoperative clinic notes, imaging, bloods, microbiology and operation notes (primary and revision) were accessed to confirm they met inclusion criteria

Results:
125 revision knee procedures of which 55 were first revisions of primary total knee replacements.
30 of 55 (55%) were NexGen knees with 22 having failed in the common pattern.
The average time from primary operation to listing for revision was only 63 months

Conclusions:
With >3000 replacements having been put in at Southampton and failure between 21 and 206 months in this cohort there is a potential exponential increase in revisions coming.
We feel group wide follow up should be initiated and any patients reporting pain should have a work-up including a SPECT CT.

Authors:
Alex Denning, Fadi Hindi, Harry Smeeden, Leonidas Vachtsevanos

Hospital:
Salisbury District Hospital NHS Foundation Trust

Introduction:
Evidence shows both intravenous and topical tranexamic acid (TXA) in primary total knee arthroplasty (TKA) reduces post operative haematoma formation and blood loss. Blood loss is associated with increased length of stay and prosthetic joint infection (PJI). Our work looked at whether addition of topical TXA to intravenous use increased total length of stay and incidence of PJI following TKA.

Methods:
We retrospectively looked at 100 patients who underwent primary TKA from 2019. Outcomes measured were length of stay and revision for infection in the 2 years following the procedure. All patients were required to have TXA at induction and the groups were then split into those who had topical intraarticular TXA and those who did not at the end of the procedure.

Results:
97 patients met the inclusion criteria. Of those patients, 51 had TXA given topically and 46 did not. Average age for TXA group was 73.1 and non-TXA 73.2. Average BMI for the TXA group was 33.0 and non-TXA 32.6. The TXA group lost on average 12g/L of haemoglobin and non-TXA group lost 15G/L between pre and post op bloods. The TXA group had an average inpatient stay of 4.1 days, whereas the non-TXA group was 3.9 days. There were no PJI in either group.

Conclusions:
There appears to be little advantage to giving topical TXA as well as intravenous TXA. Although there appeared to be a small reduction in Intra-operative blood loss, this had no effect on length of stay or likelihood of developing PJI within 2 years.

Authors:
Fransiska Guerreiro, Daniel Blyth, Vitali Goriainov, Andy Langdown

Hospital:
Queen Alexandra Hospital

Introduction:
The management of patients with rotational malalignment of the hip resulting in impingement is complex, especially if compounded by intra-articular pathology. Rotational correction of the proximal femur can be stabilised with either plates or intramedullary nails. We reviewed these methods of proximal femoral rotational correction when combined with hip arthroscopy.

Methods:
We reviewed patients that underwent concurrent ipsilateral hip arthroscopy and proximal femoral derotation osteotomy (PFDO) for proximal femoral retroversion. PFDO was either stabilised with a plate (PS) or intramedullary nail (IMS). We analysed operative time, blood loss, time-to-union (radiologic), pain and functional outcomes.

Results:
Each group consisted of 7 patients with an average age at operation of 22 (PS) and 27 (IMS) years. All patients had associated intra-articular bony pathomorphology (CAM/pincer lesions and labral tears) treated during hip arthroscopy as the first step. Average proximal femoral retroversion was 5° (PS) and 7° (IMS). Subsequent PFDO operative time was 118 (105-130) and 95 (80-105) mins in PS and IMS groups, respectively. Blood loss was 450 (PS) and 280 mls (IMS). Average time-to-union was 8 and 7.6 months in PS and IMS groups, respectively. Average score improvements from pre-op to 12 months post-op were assessed using a VAS score, iHOT12, NAHS and UCLA.

Conclusions:
The outcomes of PFDO stabilised with IM nail were superior to the plate. We feel that in the presence of combined intra- and extra-articular pathomorphology contributing to the FAI phenomenon which has failed to resolve non-operatively, both aspects need to be addressed.