Total Hip Arthroplasty (THA) and Hip Hemiarthroplasties (HA) are successful, cost-effective procedures that improve quality of life. Dislocation is a well recognised complication with a significant health and economic burden. We aim to establish the current management practices across the United Kingdom (UK) for Prosthetic Hip Dislocations (PHD). Our definition of a PHD includes; THA, HA and revision THA.

This national study builds on our regional pilot study and records one of the largest datasets of Prosthetic Hip Dislocation management within the UK.

A trainee-led collaborative; the North West Orthopaedic Research Collaborative (NWORC). Conducted a retrospective audit, registered as Quality Improvement (QI) projects, collected data from 38 hospital trusts across the UK.

Data was collected on patient-related factors, inpatient management, and outpatient follow up of each PHD episode between January and July 2019. Primary outcome measured definitive management, in the form of revision surgery or the consideration for this through a referral pathway.

A total of 673 (THA 504, Revision THA 141, HA 28) patients were included with a total of 740 dislocation episodes. Mean age was 75.6 years with female to male ratio 2:1. The majority of PHDs were a result of a low energy mechanism (98.7%) and presented over 6 months post index procedure (80.5%). Over half (53.8%) attended with a first or second time dislocation. Only 29.9% patients received onward revision referral; whereas 70.1% followed diverse management patterns, including local non-arthroplasty and primary arthroplasty surgeon follow-ups. Revision THAs had higher rates of referral for revision (p<0.001) compared to primary THA and HA dislocations.

A high number of PHDs present across the UK, with under a third receiving definitive management plans. This variation increases the economical burden to the National Health Service, highlighting the need for national guidance to manage these complex patients.

Aims

Patient decision aids have previously demonstrated an improvement in the quality of the informed consent process. This study assessed the effectiveness of detailed written patient information, compared to standard verbal consent, in improving postoperative recall in adult orthopaedic trauma patients.

Total Hip Replacements (THR) and Hip Hemiarthroplasties (HA) are both successful and common orthopaedic procedures. Dislocation is a well-recognised complication carrying significant morbidity and, in some cases, increased mortality risks. We define prosthetic hip dislocations (PHDs) to include both THRs and HAs. Prosthetic Hip Dislocations (PHDs) are a common acute admission yet there are no published guidelines or consensus on management following reduction.

A retrospective audit was undertaken by the North West Orthopaedic Research Collaborative (NWORC) between January 2019 and July 2019. A questionnaire was used to capture the management of each dislocation episode presenting to 11 Hospital trusts. The study was registered as a Quality Improvement (QI) project at each site. Data regarding the surgical management physiotherapy input, ongoing care and further management plans were recorded.

A total of 183 patients with 229 dislocations were submitted for initial analysis (171 THRs, 10 HAs, 2 PFRs). Female to male ratio was 2:1 with mean age of 76.7 years. Average time to first dislocation was 8.1 years. 61.1% were first or second time dislocators and 38.9% presented with 3 or more dislocations. Initial reductions were predominantly attempted in theatre (96.5%, n=221) with only 3.5% (n=8) attempted in the emergency department. In theatre 89% (n=201) were reduced closed. There was no plan for revision surgery in 70.6% cases with no difference seen between patients with >=3 dislocations and <=2 dislocations. Of the patients with a revision plan, 71% of these were performed or planned locally.

The high number of patients with 3 or more dislocations and the lack of plans for definitive interventions in the majority of cases highlights the significant variation in the management of this complex group of patients. This variation in the quality of care increases the burden on the National Health Service through repeat hospital episodes. We aim to roll out this study nationally to assess regional variations and ultimately make the case for national guidance on the management of prosthetic hip dislocations.

Background

Lateral Unicompartmental Knee Arthroplasty (UKA) is a recognised treatment option in the management of lateral Osteoarthritis (OA) of the knee. Whilst there is extensive evidence on the indications and contraindcations in Medial UKA there is limited evidence on this topic in Lateral UKA. The aim of this study was to assess our experience of mobile lateral UKR and to look specifically at the effect of Contraindications on the outcome.

Distal femoral physeal fractures can cause of growth distrurbance which frequently requires further surgical intervention. The aim of this study was to determine if tibial tuberosity ossification at the time of injury can predict further surgery in patients who have sustained a physeal fracture of the distal femur.

We retrospectively investigated all patients who had operative treatment for a distal femoral physeal fracture at a paediatric level one trauma center over a 17 year period. Logistic regression analysis was performed investigating associations between the need for further surgery to treat growth disturbance and tibial tuberosity ossification, age, Salter Harris grade, mode of fixation or mechanism of injury.

74 patients met the inclusion criteria. There were 57 boys (77%) and 17 girls (23%). The average age at time of injury was 13.1 years (range 2.-17.1 years). Following fixation, 30 patients (41%) underwent further surgery to treat growth disturbance. Absence of tibial tuberosity fusion to the metaphysis was significantly associated with need for further surgery (p = < 0 .001). Odds of requiring secondary surgery after tibial tuberosity fusion to metaphysis posteriorly (compared with not fused) were 0.12, 95% CI (0.04, 0.34). The estimate of effect of tibial tuberosity ossification on reoperation rates did not vary when adjusted for gender, mechanism, fixation and Salter Harris grade. When accounting for age, the odds of further operation if the tibial tuberosity is fused to the metaphysis posteriorly (compared with not fused) were 0.28, 95% CI (0.08, 0.94).

Tibial tuberosity ossification stage at time of injury is a predictor of further surgery to treat growth disturbance in paediatric distal femoral fractures. Children with distal femoral physeal fractures whose tibial tuberosity was not fused to the metaphysis posteriorly were 8.3 times more likely to require further surgery.

Introduction

The revision rate of unicompartmental knee replacement (UKR) in national joint registries is much higher than that of total knee replacements and that of UKR in cohort studies from multiple high-volume centres. The reasons for this are unclear but may be due to incorrect patient selection, inadequate surgical technique, and inappropriate indications for revision. Meniscal bearing UKR has well defined evidence based indications based on preoperative radiographs, the surgical technique can be assessed from post-operative radiographs and the reason for revision from pre-revision radiographs. However, for an accurate assessment aligned radiographs are required. The aim of the study was to determine why the revision rate of UKR in registries is so high by undertaking a radiographic review of revised UKR identified by the United Kingdom's (UK) National Joint Registry (NJR).

Aim

Spondylodiscitis and vertebral osteomyelitis can lead to long-term sequelae if not diagnosed and treated promptly and appropriately. The Royal National Orthopaedic Hospital (RNOH) has devised a new spinal infection referral system within the UK that allows cases to be discussed in a specialist multi-disciplinary (MDT) forum. National guidelines were devised in 2013 to help guide treatment, which recommends both tissue biopsies from the affected region and a MRI of the entire spine. The aims of this study were to assess the current treatment and referral practices and compare them with the set guidelines. It is hypothesised that a high percentage of patients are started on antibiotics without a biopsy or a positive set of blood cultures, a low percentage of patients are referred without undergoing a MRI of the full spine and that there is a long delay in referral to the MDT.

Title

3D distribution of cortical bone thickness in the proximal humerus, implications for fracture management.

Background

Reverse Geometry shoulder replacement requires fixation of a base plate (called a metaglene) to the glenoid to which a convex glenosphere is attached. Most systems use screws to achieve this fixation. The suprascapular nerve passes close to the glenoid and is known to be at risk of injury when devices and sutures are inserted into the glenoid. We investigate the risk posed to the suprascapular nerve by placement of metaglene fixation screws.

Purpose

Locking plates are widely used in clinical practice for the surgical treatment of complex proximal humerus fractures, especially in osteoporotic bone. The aim of this study is to assess the biomechanical influence of the infero-medial locking screws on maintaining reduction of the fragments in a proximal humerus fracture.

Introduction

Osteochondral lesions of the talus are common injuries following acute and chronic ankle sprains and fractures, the treatment strategies of which include both reparative and restorative techniques. Recently, restorative techniques (i.e., autologous osteochondral transplantation) have been become increasingly popular as a primary treatment strategy, in part due to the potential advantages of replacing “like with like” in terms of hyaline cartilage at the site of cartilage repair. The current study examines the functional results of autologous osteochondral transplantation of the talus in 72 patients.

Introduction

Fractures of the proximal humerus represent a major osteoporotic burden. Recent developments in CT imaging have emphasized the importance of cortical bone thickness distribution in the prevention and management of fragility fractures. We aimed to experimentally define the CT density of cortical bone in the proximal humerus for building cortical geometry maps.

Although total hip arthroplasty (THA) has been shown to be a cost-effective means of treating hip arthritis, there is some ambiguity within the literature as to its success in those over 80 years of age. With the rapid expansion of this population group and an estimated 40% rise in THA figures expected by 2026, this study aims to review the results of primary THA in the octogenarian population. A series of 510 consecutive cases was obtained from the local arthroplasty database, consisting of all patients aged 80 years and over who underwent primary THA between 1994 and 2004. A control group of 3404 individuals under 80 years was also established using the same database and inclusion criteria. Mean follow-up for the octogenarian group was 5.9 years. Pain scores were comparable five years post-operatively in both groups (P=0.479); in particular 81.5% of octogenarians and 80.2% of the control noted no pain. Pre-operatively, the mean Harris Hip Function and Harris Hip Score were significantly lower in the octogenarian group by 4.3 and 4.2 points (P< 0.001), respectively, and at five years follow-up were also lower by 8.4 and 8.0 points, respectively (P< 0.001). Median hospital stay was three days longer in the elderly population (12 cf 9, P< 0.001). More complications occurred in the octogenarian group (38.1% cf 28.7% of controls, P< 0.001) however fewer cases of revision were noted (1.4% cf 3.8%, P=0.005). Kaplan-Meier analysis found implant survival time to revision to be comparable in both groups (mean 16.4 years in control cf 14.3 years in octogenarian, P=0.17). Patient satisfaction was also similar (97.8% in octogenarians and 98.1% in controls, P=0.741). This study suggests that individuals over 80 years of age have comparable pain improvement and overall satisfaction, low revision rates, reduced functional improvement and are more prone to complications compared to younger patients.

Background

The treatment of olecranon fractures frequently involves the use of tension band fixation. Although associated with high union rates, this method has a high incidence of morbidity associated with soft tissue compromise and limitation of range of movement requiring frequent re-operation for removal of metal.

Background: This study was carried out to record and compare the opinions of junior and senior orthopaedic surgeons with regards to the amount of training necessary to achieve competency in knee arthroscopy.

Methods: At a recent international orthopaedic conference a questionnaire was given to 50 orthopaedic residents and 40 consultants. Consultants were also asked if they performed regular knee arthroscopy (> 50/year). Competency for this study was deWned as the ability to perform the procedure without supervision.

Participants were asked to estimate the number of times a trainee needs to do the following procedures to achieve competency: diagnostic scope, partial medial meniscectomy, partial lateral meniscectomy, and anterior cruciate ligament (ACL) reconstruction.

Results: Participants completed the questionnaire immediately ensuring a 100% response. Of the 40 consultants, 22 performed regular knee arthroscopy. The greatest similarity was between the opinions of the consultants who performed regular knee arthroscopy and the junior surgeons, for both diagnostic and partial medial meniscectomy. There was a substantial diVerence in opinion for partial lateral meniscectomy and ACL reconstruction, with junior surgeons estimating a much greater amount of practice being needed to achieve competency. Consultants who did not perform regular knee arthroscopy consistently estimated approximately half the number of operations when compared to others.

Conclusions: The information presented in this study demonstrates the opinions of both junior and senior surgeons as to how many repetitions of four common arthroscopic procedures are necessary to achieve competency: this information may be useful in designing eVective arthroscopic training programmes.

Background: Fixation of complex fractures of the proximal humerus is challenging. Fixed angle plates have been shown to give good results in younger patients with good bone quality, however failure of screws to maintain fixation in older patients remains a problem [1]. It has been shown that the bone quality within the humeral head sharply declines with age leaving a large bone void [2]. We propose that filling this bone void with a synthetic bone graft will improve screw purchase, and reduce the likelihood of construct failure.

Aims: We aim to use CT based finite element analysis to examine the effect of augmenting plate fixation with synthetic bone graft in the presence of a poor bone stock.

Methods: A computer tomography (CT) scan of an intact cadaveric fresh frozen humerus from a 78 year old male was obtained. The CT Hounsfield units were calibrated using a water phantom. Both the external contour and internal structure of the hummers were accurately defined using the threshold method. Using proprietary software [Simpleware Simpleware Ltd., Exeter], Boolean subtraction was employed to simulate an anatomically reduced four-part proximal humerus fracture with a representative bone void within the humeral head. A digital representation of a fixed angle proximal humerus plate was created and located so as to fix the fracture. The geometry of the plate fixed four-part fracture was then used to create a hexa-hederal dominant finite element mesh with over six hundred thousand elements created. Linear elastic properties were assigned to each element within the mesh representing bone using established relationships based on local Hounsfield number in the original CT scan [3]. The model was imported into the finite element preprocessor [Abaqus CAE, Simulia Inc, USA]. Contact interactions between the bone fragments, implant and bone graft substitute were defined. A pressure load was applied to the articular fragment to simulate maximum physiological joint reaction forces on the proximal humerus [4,5]. Simulations were run on the facilities at the Irish Center for High End Computing (ICHEC) The effect of adding synthetic bone graft to fixation with a fixed angle device was studied.

Results: In all models the peak pressures were along the lateral cortex and at the implant bone interface. This agrees with common clinical modes of failure being lateral collapse, valgus impaction and cutout of screws into the glenoid fossa. Finite element models where the simulated bone void was filled with bone graft substitute showed 60% reduction in the bearing pressures at the implant/bone interface.

Conclusions: Our results suggest that augmenting plate based fixation of complex proximal humerus fractures with synthetic bone graft results in a more robust construct. It a clinical setting this is likely to result a lower incidence of failure of fixation and subsequent revision surgery.

We reviewed a single-surgeon series of 300 athletic patients who had undergone reconstruction of the anterior cruciate ligament in order to establish the relationship between the timing of the reconstruction and the incidence of meniscal and chondral pathology. The patients were divided into five groups according to the time from their injury to surgery as follows: less than two months, two to six months, six to 12 months, 12 to 18 months and more than 18 months. The presence of meniscal tears was recorded and chondral pathology was scored according to the system of the French Society of Arthroscopy.

There was a significantly higher chance of a medial meniscal tear occurring in patients undergoing reconstruction after one year from their injury (odds ratio (7.99, p = 0.004). The odds of having a lateral meniscal tear did not change significantly with an increasing interval to reconstruction. The chance of patients developing degenerative changes was found to be significantly higher in the groups operated on after six months from injury (odds ratio 4.04, p = 0.005).

We advocate that patients with deficiency of the anterior cruciate ligament should be counselled that there is a significant relationship between the duration of the instability of their knee and the subsequent incidence of both chondral changes and meniscal tears. In order to minimise these risks, we recommend that reconstruction be performed within the first year from injury.

High complication rates and technical difficulties of intramedullary fixation in children with osteogenesis imperfecta have prompted the modification of existing rod systems. The Sheffield telescoping intramedullary rod system was introduced to reduce the complications. It has a T-piece which is permanently fixed to prevent its separation and is expanded to reduce the migration. This study analyses the outcome of this rod system over a 12-year period in two specialist centres.

Sixty rods were inserted in the lower limbs of 19 children with osteogenesis imperfecta. All children had multiple fractures of the bones before rod insertion. 39 rods were inserted into the femur, of which 3 were exchange and 4 revision procedures. 21 rods were inserted in the tibia. Eight children had intramedullary rodding of all the four lower limb long bones. The outcome was measured in terms of mobility status, incidence of refractures and rod-related complications.

Our series demonstrates that there is significant reduction in refractures and improvement in the mobility status in children with osteogenesis imperfecta following intramedullary fixation. The frequent complication of T-piece separation and the need for reoperation has been overcome with the Sheffield modification of rod design. But the extracortical and metaphyseal migration of the rod continues to be a problem and further improvement in the design is desirable.

To date the principal focus of the mechanism of cervical spine fracture has been directed towards head/neck circumference and vertebral geometric dimensions. However the role of other measurements, including chest circumference and neck length, in a standard cervical fracture population has not yet been studied in detail. Cervical fractures often involve flexion/extension type mechanisms of injury, with the head and cervical spine flexing/extending, using the thorax as an end point of contact. Thus, the thorax may play an important role in neck injuries.

Study design: We prospectively studied all patients with cervical spine fractures who were admitted to the National Spinal Injuries Unit from 1 July 2000 to 1 March 2001. Anthropometrical measurement of head circumference, neck circumference, chest circumference, and neck length were analysed. Ages ranged from 18 to 55 years, and all patients with concomitant cervical pathology were excluded from the study. Mechanism of injury involved flexion/extension type injuries in all cases; those with direct axial loading were excluded. A control group of 40 patients (age 18–50 years) involved in high velocity trauma with associated long bone fractures, in whom cervical injury was suspected, but who were without any cervical fracture, or associated pathology, were similarly measured.

Results: Our analysis revealed a statistically significant increase in chest size in the male control group versus the male fracture group (97.89 cm versus 94.19 cm, P < 0.05, Student’s t-test). There was a correspondingly significant increase in chest circumference between the female controls versus the female fracture group (92.33 cm versus 88.88 cm, P < 0.05, Student’s t-test). Our results revealed no statistical difference in head circumference, neck circumference, or neck length between each of the groupings. These results indicate a proportionately larger chest may be a protective factor in cervical spine fractures.

Polyethylene wear in total hip arthroplasty Is associated with generation of particulate wear debris and component failure. Wear has both mechanical and biological consequences with one of the most important of these being the stimulation of immune medicated periprosthetic osteolysis in response to polyethylene particles. It has been shown that the amouont of wear debris generated correlates with the degree of osteolysis encountered. Unfortunately, the assessment of wear of components remains difficult and we wished to apply a new digitised technique of measuring wear using engineering computer softwear on a population of uncemented total hip replacement (THR) patients.

Forty patients having primary uncemented THR (ABG 1 prosthesis) for osteoarthritis were enrolled in the study. Seventeen had a 28mm femoral head implanted and 23 had a 32mm head. There were 28 females and 12 males concerned, all having standardised (120 cm hip to x-ray tube) ;weight bearing antero-posterior plain radiographs of the hip performed in the immediate post-operative period and again at a mean of 6 years post-operatively (range 54 – 96 months). The x-rays were then scanned to computer and analysed using Autocad software. The analysis essentially involved 4 steps, namely assessing sphericity of the cup, sphericity of the head, superimposition of the post-operative and 6 year radiographs an.d obtaining computer generated analysis of both the amount and direction of wear.

The results of our analysis demonstrated that there was an overall mean wear of 0.157mm per year (range 0.08 – 0.27mm). Of the 17 patients with a 28mm head the mean wear was 0.143mm per year, whereas the 32mm heads were associated with a mean wear rate of 0.188mm per year, with the difference reaching statistical significance (p=0.004). Analysis of the direction of wear demonstrated that as expected wear typically occurred in a superolateral direction with a mean vector of 9° lateral to the vertical axis of the hip.

These results primarily demonstrate the usefulness of appropriate computer software in determining wear of components in THR. This allows for assessment of rate and degree of wear which may be important in identifying patients at particular risk of developing significant osteolysis, loosening and ultimately component failure. The results are also consistent with previous reports of increased volumetric wear with large diameter heads and direction of wear in retrieval studies. It is therefore promising as an investigative tool for the in vivo assessment of inovations in THR design in the future.