Temporal Trends and Survivorship of Total Hip Arthroplasty in Very Young Patients

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.

Mid-Term Functional Outcomes & Cobalt Chromium Levels Following Ceramic on Metal Total Hip Replacement

Nisarg Mehta, Justin Leong, Philip Brown, Dhawal Patel, Hussain Kazi , Fintan Adrian Carroll

Background: With controversies surrounding Metal on Metal (MoM) total hip arthroplasty (THA); alternate bearing surfaces such as Ceramic on Metal (CoM) had a surge in popularity. However, there are reports of higher than expected rate of revision and elevated serum metal ions and radiolucent lines (RLL) at mid-term follow-up. The aim of this study was to report functional & radiological outcomes of CoM THAs performed at our institution.

Methods: Patients undergoing CoM THA between 2008 and 2010 were identified and brought back for followup in 2017 where up-to-date radiographs, Oxford Hip Scores & Cobalt Chromium levels were taken. The primary outcome measure was mean oxford hip score at follow-up. Secondary outcome measures included serum cobalt chromium levels & revision surgery.

Results: A total of 114 CoM THAs were performed on 94 patients with a mean follow-up of 76.8 months (0-120) and a median age of 58 (42-70). The mean socket size was 54mm (42-70), median femoral head size was 36mm (28-36) & mean inclination was 42.3 0 (31 0 -61 0 ). There was a significant improvement between preoperative & mean follow-up oxford hip scores [Preoperative 14.6 (2-36), Follow-Up 45.7(32-48) p<0.001]. Of the 83 patients that survived the mean serum cobalt and chromium levels were 41nmol/L (3-678) & 41nmol/L (0-196). 13 patients had radiolucent lines >1mm in at least 1 Gruen Zone. 98% of patients have well-functioning hips at follow-up with 2 patients undergoing revision with pain & elevated metal ion levels above MHRA thresholds.

Conclusions: Majority of patients with CoM THAs remain asymptomatic and have good functional outcomes at mid-term follow-up. However, we note higher than expected serum metal ion levels and presence of RLL in certain patients

Implications: Despite having high functioning hips, all patients with CoM THAs should be followed-up long term with annual radiographs and serum metal ion levels


Pre-operative Skin preparation for Hip and Knee Arthroplasty

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.

Does Nottingham Hip Fracture Score Predict Mortality in Distal Femoral Fracture Patients?

Ignatius Liew, Joseph Attwood, Siddhant Kumar, Nameer Choudry, James Fountain

Background: Patients with distal femoral fractures are associated with similar high rates of mortality to neck of femur fractures. Identifying high risk patients are crucial in pre-operative medical optimisation, risk stratification for anaesthetics and orthogeriatric input. Nottingham Hip Fracture Score (NHFS) has been validated as a predictor of mortality in neck of femur fracture patients, especially in those with score of ≥5 as high risk. We investigated the validity of NHFS in predicting 1 year mortality of patients sustaining distal femoral fractures.

Methods: All patients admitted to a level 1 major trauma centre with distal femoral fractures were retrospectively reviewed between June 2012 and October 2017. NHFS were recorded using parameters immediately pre-operatively.

Results: 92 patients were included for analysis with mean follow-up of 32 months, mean age of 69 (range 16-101). 56 (61%) of patients were female, 10 (11%) were open fractures and 32 (35%) were periprosthetic fractures with 77 (85%) patients surgically managed. 41 patients were found to have NHFS ≥5. Overall mortality at 30 days was 7% and 1 year was 33%. Patients with NHFS of <4 had a higher survival rate at 30 days (96% vs 90%) and at 1 year (74% vs 49%, p=0.002) when compared with those of higher risk (NHFS ≥5) On Kaplan-Meier plotting and Log-Rank test, patients with a NHFS of ≥5 were associated with a higher mortality (p=0.0001).

Conclusion(s): NHFS can be used to stratify distal femur fracture patients, identifying those with high risks of mortality. NHFS is a validated tool not only in hip fracture but also distal femoral fractures in risk stratifying patients for pre-operative optimisation as well as predictor of mortality at 30 days and 1 year.

A New Local Guideline for Hip Fracture Patients Taking Direct Oral Anticoagulants (DOACs)

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.

MethodsA 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).

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


Modular hip hemiarthroplasty for narrow femoral canal – Is it a true Indication?

Ignatius Liew, Khaldoun Bitar, Justin Leong, Nameer Choudry, James Fountain

Background: The modular prosthesis is sometimes favoured for sizing options in narrow femoral canals despite no advantage in clinical outcomes with higher cost for displaced intracapsular femoral neck fractures. This study aimed to investigate factors affecting surgeons’ choice of using modular hip hemiarthroplasty instead of monoblock design and to determine whether it was justifiable.

Methods: All femoral neck fractures from March 2013 to December 2016 were reviewed. Modular hemiarthroplasty performed for a narrow femoral canal were included, with a patient-matched group of patients who had undergone monoblock hemiarthroplasty. Satisfactory lateralisation and alignment of the femoral stem were measured. Patients who received modular hemiarthroplasty were templated on radiographs using TraumaCad for Stryker® ETS design.

Results: A total of 553 hemiarthroplasty were performed, of which 27 were modular hemiarthroplasty performed for narrow canals, with a ratio of modular to monoblock was 1:18. Average head side for monoblock and modular hemiarthroplasty were 46.7mm±3.6 and 44.07±1.5 (p=0.001) respectively. There were 4 malaligned stems in monoblock group versus 14 in the modular group (p=0.008). 18 (7mm±2.9) patients had unsatisfactory lateralisation in the Modular group as compared to 8 (4.7mm±3.9) in the monoblock (p=0.029). 24 patients were classified as Dorr A and B in the Modular group as compared to 18 in the monoblock (P=0.006). 2 (7%) patients who did not achieve 2mm cement mantle on templating.

Conclusion: Patients perceived to have narrow femoral canals intraoperatively should not be immediately converted to a modular implant prior to a thorough check of the position of the implant. Female patients with small femoral head size, Dorr A and B need careful planning. Surgical techniques should be explored through education in achieving lateralisation during femoral stem preparation to avoid prolonged anaesthetic time and achieving cost saving.


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.

Prevalence of Venous Thrombo-Embolism in Patients with Total Contact Cast

Mr J Widnall, Dr X Tonge, Mr S Platt, Miss G Jackson

Background: Venous Thrombo-Embolism is a recognized complication of lower limb immobilization. In the neuropathic patient, limb immobilization, in the form of total contact casting (TCC), is used in the management of acute charcot neuroathropathy and/or to off-load neuropathic ulcers. There is currently no literature stating the prevalence of VTE in patients undergoing TCC. There are also no recommendations regarding VTE prophylaxis in the setting of TCCs. We aim to perform a retrospective case series assessing the prevalence of VTE in the patients being treated with TCCs. Given the multitude of co-morbidities that exist within this heterogeneous group of patients we hypothesize the rate of VTE is higher than that of the general population.

Methods: Patients undergoing TCC between 2006 and 2018 were identified using plaster room records. These patients subsequently had clinical letters and radiological reports assessed for details around the TCC episode, past medical history and any VTE events.

Results: There were 143 TCC episodes in 104 patients. Average age at cast application was 55 years. Time in cast averaged 45 days (range from 5 days to 8 months). 3 out of 4 patients had neuropathy as a consequence of diabetes. One TCC related VTE (0.7% of casting episodes) was documented. This was a proximal DVT confirmed on USS 9 days following cast removal. No patient received VTE prophylaxis while in TCC

Conclusion: Despite these complex patients having a multitude of co-morbidities the prevalence of VTE in the TCC setting remains similar to that of the general population. This may be due to the fact that TCCs permit weight bearing. This case series suggests that, while all patients should be individually VTE risk assessed as for any lower limb immobilization, chemical thromboprophylaxis is not routinely indicated in the context of TCCs.


Anatomy of the Lateral Plantar Ligaments of the Transverse Metatarsal Arch -The Lateral Lisfranc Ligament

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 2nd to the 5th 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.

Do protocols improve VTE prophylaxis in practice?

Andrew McNally, William Marlow, Stephen Lipscombe

Background: VTE prophylaxis practice varies between/within hospitals. There is poor consistency particularly in treating NWB patients immobilised in casts. This inconsistency was previously demonstrated in an initial audit. The solution had been to implement a protocol based on national guidelines.

Methods: A retrospective analysis of 40 patients was conducted to ascertain the impact of the changes. Data was collected from notes and pharmacy records. Data from the initial cycle was extracted to identify patients matching the inclusion criteria for the protocol for comparison with the second cycle.

Results: This cycle demonstrated a fall in documentation of risk factors from 42% to 27%. Documentation of bleeding risk was seen in only 3%. Despite this, there were only 4 cases where no prophylaxis was prescribed and there was no documentation. Retrospective analysis of these cases could identify no risk factors which would have mandated prophylaxis. The proportion of cases not prescribed prophylaxis fell from 35% to 10% - whether this change was appropriate is not known due to the high rate of poor documentation.

Discussion: Following the implementation of protocols, the proformas were rarely used and documentation of risk factors in dictated letters fell significantly. Although the rate of prescription increased significantly, it is not clear whether this was appropriate – the documentation was insufficient where it was prescribed. 90% prescription may reflect an overly aggressive reactive response to the previous audit presentation. The audit process may have highlighted the issue and proformas, however knowledge of these proformas was virtually non-existent among doctors on rotation.

Conclusion: Without first improving documentation we cannot assess the impact of our changes. The changes implemented initially were lost when that cohort of doctors rotated. Failure to integrate the changes into the existing culture of the permanent MDT staff are likely to have contributed to this transiency.