Aims

We aim to evaluate the usefulness of postoperative blood tests by investigating the incidence of abnormal results following total joint replacement (TJR), as well as identifying preoperative risk factors for abnormal blood test results postoperatively, especially pertaining to anaemia and acute kidney injury (AKI).

Primary total joint arthroplasty (TJA) is an increasingly common and safe way of treating joint disease. Robust preoperative assessment improved intraoperative techniques and holistic rehabilitation contribute to an uneventful postoperative period. Despite there being evidence against the utility of postoperative blood tests, it is still often part of routine practice. We aim to evaluate the usefulness of these tests by investigating their incidence following TJA as well as identifying preoperative risk factors for abnormal blood test results postoperatively especially pertaining to anaemia and acute kidney injury (AKI).

This is a retrospective cohort study of patients who had elective TJA between January and December 2019 at a tertiary centre. An independent student's t-test and Fisher's exact test was used to compare variables between the normal and abnormal postoperative results groups. An analysis of variance (ANOVA) was performed to identify risk factors for an abnormal blood test result. Analyses of receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used to determine cut off values that could be suggestive of abnormal test results postoperatively.

The study included 2721 patients with a mean age of 69 of which 46.6% were males. Abnormal postoperative bloods were identified in 444 (16.3%) patients. We identified age (≥65 years), female gender, ASA ≥ 3 as risk factors for developing abnormal postoperative blood tests. Preoperative haemoglobin (≤ 127 g/dL), haematocrit (≤ 0.395L/L) and potassium (≤ 3.7 mmol/L) were noted as cut-offs that could be predictive of postoperative anaemia or AKI respectively.

The costs outweigh the benefits of ordering routine postoperative blood tests in TJA patients. Clinicians should risk stratify their patients and have a lower threshold for ordering blood tests in patients with one or more of the risk factors we have identified. These risk factors are age (≥65 years), females, ASA ≥ 3, preoperative haemoglobin (≤ 127 g/L), haematocrit (≤ 0.395L/L), and potassium (≤ 3.7 mmol/L).

Purpose of the study and background

Although pain is usually described as a private experience, how pain is understood and responded to by others is important. A crucial feature of this process is empathy. The aim of this study was to examine the relationship between empathy for pain and observers' health anxiety and fear of pain. The role of the observer's sex and age were also examined.

Introduction

Hip arthroscopy is a relatively new procedure and evidence to support its use remains limited. Well-designed prospective clinical trials with long-term outcomes are required, but study design requires an understanding of current practice. Our aim was to determine temporal trends in the uptake of non-arthroplasty hip surgery in England between 2001 and 2011.

Introduction

Subtle deformities of the acetabulum and proximal femur are recognised as biomechanical risk factors for the development of hip osteoarthritis (OA) as well as a cause of hip and groin pain. We undertook this study to examine relationships between a number of morphological measurements of the acetabulum and proximal femur and the hip pain in a 20-year longitudinal study.

Introduction

Malalignment of some designs of stem is associated with an increased risk of aseptic loosening and revision. We investigated whether the alignment of the cemented polished, double-taper design adversely affected outcome, in a multicentre prospective study.

INTRODUCTION

The introduction of hard-on-hard bearings and the consequences of increased wear due to edge-loading have renewed interest in the importance of acetabular component orientation for implant survival and functional outcome following hip arthroplasty. Some studies have shown increased dislocation risk when the cup is mal-oriented which has led to the identification of a safe-zone1. The aims of this prospective, multi-centered study of primary total hip arthroplasty (THA) were to: 1. Identify factors that influence cup orientation and 2. Describe the effect of cup orientation on clinical outcome.

Introduction

The results of the original mobile bearing Oxford unicompartmental knee replacement (UKR) in the lateral compartment have been disappointing because of high dislocation rates (11%). This original implant used a flat bearing articulation on the tibial tray. To address the issue of dislocation a new implant (domed tibia with biconcave bearing to increase entrapment) was introduced with a modified surgical technique. The aim of this study was to compare the risk of dislocation between a domed and flat lateral UKR.

Introduction: The use of highly cross-linked polyethylene (HXLPE) is now commonplace for total hip arthroplasty, however there is no long-term data to support its use. Hip simulator studies suggest that the wear rate of some types of HXLPE is ten times less than conventional polyethylene (UHMWPE). The outcomes of hip simulator studies are not always reproduced in vivo and there is some evidence that HXLPE wear may increase between 5 and 7 years.

Method: A prospective double blind randomised control trial was conducted using Radiostereometric Analysis (RSA). Fifty-four subjects were randomised to receive hip replacements with either UHMWPE liners or HXLPE liners. All subjects received a cemented CPT stem and uncemented Trilogy acetabular component (Zimmer, Warsaw, IN, USA). The 3D penetration of the head into the socket was determined to a minimum of 7 years.

Results: The total liner penetration was significantly different at 7 years (p=0.005) with values of 0.33 mm (SE 0.05 mm) for the HXLPE group and 0.55 mm (SE 0.05 mm) for the UHMWPE group. The steady state wear rate from 1 year onwards was significantly lower for HXLPE (0.005 mm/yr, SE 0.007 mm/yr) than for UHMWPE (0.037 mm/yr, SE 0.009 mm/yr) (p=0.007). The direction of wear was supero-lateral.

Discussion: We have previously demonstrated that the penetration in the first year is creep-dominated, from one year onwards the majority of penetration is probably due to wear. This study confirms the predictions from hip simulator studies which suggest that the wear rate of this HXLPE approaches that of metal-on-metal and ceramic-on-ceramic articulations. HXLPE may have the potential to reduce the need of revision surgery, due to wear debris induced osteolysis. It may also enable surgeons to use larger couples, thus reducing the risk of impingement and dislocation.

Introduction: The use of second generation highly cross-linked polyethylene (HXLPE) is now commonplace for total hip arthroplasty, however there is no long-term data to support its use. Hip simulator studies suggest that the wear rate of HXLPE is ten times less than conventional polyethylene (UHMWPE). The outcomes of hip simulator studies are not always reproducible in vivo. Long term clinical data is required, as there is emerging clinical data, which suggests that some types of second generation HXLPE may have increased wear after 5 years.

Method: A prospective double blind randomised control trial was conducted using Radiostereometric analysis (RSA). Fifty-four subjects were randomised to receive hip replacements with either UHMWPE liners or HXLPE liners. All subjects received a cemented CPT stem and uncemented Trilogy acetabular component (Zimmer, Warsaw, IN, USA). The 3D penetration of the head into the socket was determined to a minimum of 7 years.

Results: The total liner penetration was significantly different at 7 years (p=0.01) with values of 0.33mm (SD 0.17mm) for the HXLPE group and 0.51mm (SD 0.14mm) for the UHMWPE group. The steady state wear rate from 1 year onwards was significantly lower for HXLPE (0.003 mm/yr, SD 0.04 mm/yr) than for UHMWPE (0.03 mm/yr, SD 0.03 mm/yr) (p=0.01). The direction of wear was in the antero-medial direction in both groups.

Conclusion: We have previously demonstrated that the penetration in the first year is creep-dominated, from one year onwards the majority of penetration is due to wear. The wear rate of this second generation HXLPE approaches that of metal on metal bearings. Second-generation HXLPE may have the potential to reduce the risk of revision surgery, due to wear debris induced osteolysis.

The management of spasticity of children with cerebral palsy is often complex and challenging. Effective treatment requires a multidisciplinary approach involving paediatricians, orthotists, occupational therapists, physiotherapists and orthopaedic surgeons. Botulinum toxin A therapy in the lower limb has been shown to relieve spasticity and to improve the function in the short term. However, the use of Botulinum toxin A in the upper limb remains controversial, moreover only selected few orthopaedic surgeons have experience in managing it. The aim is to assess the functional improvement following an upper limb Botulinum toxin A injections to the upper limb and then to evaluate the patient’s and parents’ satisfaction after the procedure.

During 2007 a total of 36 spastic cerebral palsy patients underwent 47 episodes of Botulinum toxin A injections to the upper limb. There were 22 male and 14 female with an age range between 2 to 17 years (average age was 2 years). Following the surgery, all patients received a course of an intense exercise regime with the physiotherapist and occupational therapist. All patients were prospectively followed-up by the clinic with no loss to follow-up. We also assessed the functional movement of the patients as well as the patient’s and parents’ subjective evaluation of the procedure.

Overall, the range of movement of the upper limb has improved following the Botulinum toxin A injection. Most patients/parents were satisfied with the procedure and would consider further injection in the future. Botulinum toxin A injection to the upper limb is generally well received with good short term results. Many would consider further injections to sustain improve function.

Antero-posterior (AP) pelvis and lateral x-rays are routinely prescribed for the positional diagnosis of proximal femoral fractures, however; the usefulness of the lateral x-ray has not been previously presented in the literature. In addition, the clinical advantage of internally rotated AP views has also not been tested. This study aims to define the value of the lateral x-ray, and the internally rotated AP view, in the assessment and treatment planning of proximal femoral fractures.

X-rays from 359 consecutive patients with proximal femoral fractures were divided into: ‘un-positioned’ AP (greater trochanter overlying the lateral femoral neck), clear neck AP (internally rotated to show the lateral femoral neck), and lateral views. Three blinded reviewers independently assessed the x-rays in sequence and noted the positional diagnosis and displacement. This was then compared with the intra-operative diagnosis used as gold standard.

The addition of a lateral x-ray to an AP view significantly increased the rate of the correct diagnosis made by the reviewers when compared to an AP view alone, in intracapsular fractures only (p < 0.013), but not for extracapsular fractures (p = 0.27).

The use of clear neck AP views did not increase the rate of correctly diagnosing the type of fracture when compared to unpositioned AP views. This applies for both intracapsular (p = 0.57), and extracapsular fractures (p < 0.823).

Although orthopaedic rote dictates that every fracture should be visualised in two views, this study has shown with that for the majority of hip fractures one view is adequate and safe. The lateral x-ray is only required for intracapsular fractures that appear undisplaced on the AP view and should not be performed routinely. Specially positioned AP views are not required and should be avoided due to the unnecessary pain caused and the needless cost.

Introduction: Disagreement exists in the literature as to whether hip resurfacing requires more acetabular reaming than uncemented hip replacement.

Materials and Methods: Thirty-nine patients underwent total hip arthroplasty with a large metal on metal resurfacing acetabular cup and large metal head with a conventional uncemented femoral stem. Although there was no change in routine operative technique the femoral neck was measured (as if for resurfacing) before being cut. The size of the acetabular component actually inserted was compared with the smallest size which could have been used had a resurfacing been carried out for each patient. A two tailed paired t test was carried out.

Results: We found that there was no difference in female patients but in men the actual cup used was 2.44mm smaller than the smallest possible resurfacing cup which equates to 6.39cm³ less bone (p < 0.0001).

Discussion: By using paired samples we have reduced confounding factors and shown that a large metal on metal bearing on a conventional stem is more conservative of acetabular bone than hip resurfacing in male patients.

Introduction: The management of spasticity of children with cerebral palsy is often complex and challenging. Effective treatment requires a multidisciplinary approach involving paediatricians, orthotists, occupational therapists, physiotherapists and orthopaedic surgeons. Botulinum toxin A therapy in the lower limb has been shown to relieve spasticity and to improve the function in the short term. However, the use of Botulinum toxin A in the upper limb remains controversial.

Aim: To assess any improvement following upper limb Botulinum toxin A injections and to evaluate patient’s and parents’ expectation and satisfaction of the procedure.

Method: During 2007 a total of 36 spastic cerebral palsy patients underwent 47 episodes of Botulinum toxin A injections to the upper limb. There were 22 male and 14 female with a mean age of 6 years old. A questionnaire was devised to assess the outpatient consultation, peri-operative care and the post-operative outcome. Subjective improvement and the patient’s and parents’ evaluation of the procedure were also recorded.

Results: Good to excellent results were achieved in most areas. Daily activities were improved by 52% with an average duration of 4 months. The majority of the patient achieved their expectation. Most patients/parents were satisfied with the procedure and would consider further injections.

Conclusions: Botulinum toxin A injection to the upper limb was generally well received with good short term results. Most would consider further injections.

Background: There has been much interest recently in reducing the length of inpatient stay after hip and knee arthroplasty and much of the relevant literature has linked this to minimally invasive surgery. Orthopaedic departments are often under great pressure to reduce inpatient stay in order to increase throughput of patients. However it is incumbent on those of us responsible for patient care to ensure that systems are in place to maintain safety.

Patients and Methods:We looked at a 6 month period of early discharge with a dedicated ‘Accelerated Discharge Team’ (A.T.T.) at our institution. The team consisted of three nurses, two physiotherapists and two ‘technical instructors’. All patients undergoing hip or knee arthroplasty were assessed pre-operatively and post-operatively for admission to the care of the A.T.T. against fixed criteria. Patients were visited at home on the day of discharge and every day until released from the care of the team. 333 patients underwent lower limb arthroplasty during the study period of which 305 (91.6%) were admitted to the care of the A.T.T.

Results: The mean lengths of stay for primary hip and knee replacements were 3.43 and 3.30 days respectively. The mean for revision hip and knee were 5.75 and 3.29 days respectively. 66% (95% C.I. 57%–74%) of patients undergoing primary hip arthroplasty went home by 3 days and 91% (95% C.I. 85%–95%) by 4 days. 73% (95% C.I. 64%–81%) of patients undergoing total knee arthroplasty went home by 3 days and 93% (95% C.I. 87%–97%) by 4 days. The most common reasons for delay were: social reasons or living alone; low blood pressure or haemoglobin level; difficulty walking. Of the 305 patients, 12 (4%) were readmitted to hospital within 6 weeks of discharge, 2 of these patients (1%) were still under the care of the A.T.T. Almost 90% of patients responded to a satisfaction survey. 94.2% of those responding indicated that they would use the A.T.T. scheme again.

Discussion: Other authors have linked early discharge to minimally invasive surgery or to special anaesthetic/ analgesic techniques. It has also been shown that both carepathways and patient education protocols can reduce length of stay. In the year before implementing the A.T.T. the mean stay for primary hip and knee replacements was over 9 days. We were able to reduce this to less than 3.5 days for over 90% of our patients during the study period. This was achieved safely and without any special surgical or anaesthetic techniques. The total cost of the scheme was just under £100 000 for the 6 month period. We estimate that 2000 bed days were saved during the same period. This is cost effective on these terms alone. As well as transferring 12 elective orthopaedic beds to a different department we were able to perform an estimated 75 extra lower limb arthroplasties in the 6 month period.

Background: It is commonly believed that early motion after joint fixation is a good thing, especially in the upper limb, but in the ankle joint this is much less clear. No previous systematic review of the evidence for this could be found in the literature.

Materials and Methods: Nine randomised Control Trials were identified which met the inclusion criteria and compared early motion of the ankle joint to immobilisation in a cast for six weeks. These varied in quality and numbers. All treated patients equally in all other respects including weight bearing. Where outcome measures were similar, some meta-analysis was possible.

Results: There is good evidence that early motion results in a quicker return to work on average (p=0.008) and results in improved range of motion at 12 weeks (dorsiflexion p= 0.001; plantarflexion p < 0.00001) compared to cast immobilisation. However it also results in an increased risk of wound infection (p=0.002). There is a suggestion that early motion results in a lower rate of deep vein thrombosis, but this is not quite significant (p=0.12). There is no evidence that it results in improved joint specific outcome scores or range of motion at 1 year.

Discussion: It is difficult to state that early motion is better or worse than cast immobilisation for every patient. The evidence suggests however that a young fit patient who needs to return to work may benefit from early motion of the ankle joint whereas an older diabetic patient with poor skin would be better treated in cast.

Aim To review 6 months of early discharge with a dedicated ‘Accelerated Discharge Team’ (A.T.T.) at our institution.

Patients and Methods The team consisted of four nurses and three physiotherapists. Patients undergoing hip or knee arthroplasty were assessed pre-operatively and post-operatively for admission to the care of the A.T.T. against fixed criteria. Patients were visited at home on the day of discharge and every day until released from the care of the team. 333 patients underwent lower limb arthroplasty during the study period of which 305 (91.6%) were admitted to the A.T.T.

Results The mean length of stay for primary knee replacements was 3.30 days. 73% (95% C.I. 64%–81%) of patients undergoing total knee arthroplasty went home by 3 days and 93% (95% C.I. 87%–97%) by 4 days. Results for hip arthroplasty were similar. Of the 305 patients, 12 (4%) were readmitted to hospital within 6 weeks of discharge. Almost 90% of patients responded to a satisfaction survey. 94.2 % of those responding indicated that they would use the A.T.T. scheme again.

Discussion In the year before implementing the A.T.T. the mean stay for primary hip and knee replacements was over 9 days. We reduced this to less than 3.5 days for over 90% of our patients during the study period. The total cost of the scheme was just under £100 000 for the 6 month period. We estimate that 2000 bed days were saved during the same period. This is cost effective on these terms alone. As well as transferring 12 elective orthopaedic beds to a different department we were able to perform an estimated 75 extra lower limb arthroplasty operations in the 6 month period.

Aim: The aim of this study was to asses the accuracy of skyline radiographs in the assessment of the patellofemoral joint, when compared to open intraoperative assessment.

Methods: Eighty nine patients undergoing knee replacement surgery were included in the study. Skyline radiographs were obtained preoperatively. These radiographs were assessed and graded by an experienced musculoskeletal radiologist using the Altman and Ahlbäck classifications. The grades were calculated for both the medial and lateral facets of the PFJ. Intraoperative assessment of the Patellofemoral joint was undertaken at the time of surgery. The damage was graded using the modified Collins classification (0: Normal, 1: Superficial damage, 2: Partial thickness cartilage loss, 3: Focal Full thickness cartilage loss < 2cm2, 4: Extensive full thickness cartilage loss < 2cm2). Data was obtained for the Medial Facet, Lateral Facet and Trochlea.

Results: Spearman’s rank correlation coefficient between the radiographic and macroscopic changes within the lateral PFJ were poor with both the Altman 0.22 (p=0.0350) and Ahlbäck 0.24 (p=0.018). The correlation of the medial PFJ was slightly better with a coefficient for Altman 0.42 (P< 0.0001) and Ahlbäck 0.34 (P> 0.001).

Conclusion: In conclusion skyline radiographs provide a poor to moderate preoperative assessment of the degree of osteoarthritis within the patella-femoral joint. This has significant implications for establishing radiographic criteria for planning patella-femoral joint replacement.

Objective: To determine the success of 20 cases treated with TomoFix high tibial medial opening wedge osteotomy.

Study design: Retrospective review of 20 cases with 6 months of follow up including; indications for treatment, surgical technique, results, complications and patient satisfaction.

Background: High Tibial Osteotomy is an established technique for the treatment of unicompartmental osteoarthritis of the varus malaligned knee. Corrections are usually achieved by closed wedge osteotomy from a lateral exposure. This technique has associated risks of; peroneal nerve injuries, instability of the osteotomy and secondary loss of correction. Open wedge osteotomy of the medial side eliminates these risks. TomoFix allows stable fixation of the osteotomy without the need to fill the osteotomy gap with bone grafts.

Results: Full weight bearing after 6 weeks. No implant failures, delayed unions, nerve injuries or compartment syndromes. Complications included 1 infection, 1 over correction and 1 with metalwork pain.

Conclusions: TomoFix allows for early mobilisation and avoids loss of correction with reduced risk of nerve injuries and compartment syndrome.

Relevance: The surgical technique needs careful attention. Disorders of normal bone healing and inadequate axial correction may lead to failure of treatment. Early rehabilitation is possible and long term follow up is necessary.

Aim: To þnd out morbidity, mortality and functional outcome in socially independent patients with displaced subcapital hip fracture, treated by primary total hip replacement.

Patients And Methods: 51 patients with displaced sub-capital fracture treated by THR at a single hospital. Average age 74 year at the time of fracture. All patients were socially independent and mentally alert. Functional outcome was assessed using patient assessed site-speciþc Oxford hip score, a generic score- SF12, and patient satisfaction. This study had a mean follow up of 33 months (Range20–54).

Results: 2% recurrent dislocation rate with 4% revision rate. 6% 1 year mortality. Median oxford hip score 16.5. Oxford hip score correlated well with both SF12 and patient satisfaction.

Conclusion: This study reports acceptable morbidity and mortality following THRoperation in select patients with displaced hip fracture. Functional outcome following THR in fracture patients found similar to that in osteoarthritic patients.

The rehabilitative phase of ankle injury management often involves the use of an ankle brace. The aim of this study was to ascertain the effects of such braces on the forces through the foot and the timing of peak loads in the gait cycle, in the recovering ankle and the uninjured ankle, in order to understand better the mechanism by which such braces enhance ankle stability.

Twenty four adults with recurrent ankle injuries and an aspiration to return to sporting activity were studied. Each was in the rehabilitation phase of recovery from ankle injury. Controls were 17 adults who regularly took part in sporting activity, without ankle injury. Assessment of peak force in three orthogonal axes (% body weight) during walking was carried out using the Kistler foot plate; the times taken to reach the maxima were recorded. Subjects were assessed in bare feet, training shoes and wearing one of two types of commonly available stirrup-type ankle braces.

Results showed that the ankle braces did not alter peak loads compared to training shoes alone (one-way analysis of variance, p< 0.05) and were consistent in both the injured and un-injured subjects. There were no significant differences between the two braces tested (p< 0.05). The time to reach peak load was not significantly different between the braced or non-braced ankles in either the injured or control groups.

Conclusions are that stirrup type ankle braces do not alter the peak forces through the foot during walking. The effectiveness of stirrup-type ankle braces appears not to depend on their modification of medial forces during gait.

The rehabilitative phase of ankle injury management often involves braces. Our aim was to ascertain the effect of both a brace on both ankle range of movement and the timing of peak loads in the gait cycle, to understand better the mechanisms by which such braces enhance ankle stability.

We recruited 24 adults who were in the rehabilitation stage following ankle injuries, and in whom there was an aspiration to return to sport.

Controls were 17 adults who regularly played sport, but had no recent history of injury.

Assessment of range of movement was carried out using the Biodex isokinetic dynamometer to measure inversion, eversion, flexion and extension of the foot, with the subject in training shoes, and wearing one of two common stirrup-type ankle braces. Assessment of peak force in three orthogonal axes (% body weight) was performed using the Kistler footplate. The subjects were observed in bare feet, trainers and stirrup braces.

Results showed that the ankle braces restricted inversion (mean reduction 9 degrees, SD 8 degrees) compared to training shoes alone in both the injured and non-injured sunjects, but the restriction in range of movement in inversion /eversion was not significantly different between the braced injured and un-injured ankles (t test p< 0.05).The ankle braces did not alter peak loads compared to training shoes alone (one way analysis of variance, p< 0.05);these findings were consistent in both groups. The time to reach peak load was not significantly different between the braced or un-braced ankles in either the injured or control groups.

We conclude that stirrup type braces reduce the range of inversion/eversion in the normal and injured ankle, reducing the movement by a similar amount in both of these groups, but they do not alter peak forces through the foot during walking.