Three distal femoral axes have been described to aid in alignment of the femoral component; the Trans Epicondylar Axis (TEA), the Posterior Condylar Axis (PCA) and the Antero Posterior (AP) axis. Our aim was to identify if there was a reproducible relationship between the axes which would aid alignment of the femoral component. This is the first study compare all three distal femoral axes with each other using magnetic resonance imaging (MRI) in a Caucasian population. Our sample group represents real life patients awaiting total knee arthroplasty (TKA), as opposed non-arthritic or cadaveric knees. We identified the relationship between these rotational axes by performing MRI scans on 89 patients awaiting TKA with patient-specific instrumentation. Measurements were taken by two observers. Patients had a mean age of 62.5 years (range 32–91). 51 patients were female. The mean angle between the TEA and the AP axis was 92.78° with a standard deviation of 2.51° (range 88° – 99°). The mean angle between the AP axis and the PCA was 95.43° with a standard deviation of 2.75° (range 85° – 105°). The mean angle between the TEA and the PCA was 2.78° with a standard deviation of 1.91° (range 0° – 10°). We conclude that while there is a reproducible relationship between the differing femoral axes, there is a significant range in the relationship between the femoral axes. This range may lead to greater inaccuracy than has previously been appreciated when defining the rotation of the femoral component. There is most variation between the PCA and the AP axis. The TEA's relationship with the PCA and AP appears important in defining rotation. Due to the well accepted difficulty in defining the TEA intra-operatively, there may be a role for patient-specific instrumentation in TKA surgery with pre-operative MRI.
Two major challenges in arthroplasty are obesity and antibiotic resistance. This study was performed to characterise the organisms responsible for deep infection following total hip arthroplasty and to determine if obesity affected the microbiology profile. A retrospective analysis of the national surgical site infection register was made to obtain data regarding deep infection following 10948 primary total hip arthroplasty (THA) from 1998–2013, with a minimum of 2 year follow-up. Of all the primary THAs performed, there were 108 deep infections (56 patients had a BMI >30 (obese) and 52 patients <30). There were no significant differences between cardio-respiratory disease, smoking and alcohol status, and diabetes between the 2 groups. Over the last 15 years, staphylococcus aureus continues to be the most frequently isolated organism. Infection with multiple organisms was found exclusively in obese patients. Furthermore, in obese patients, there was a linear increase with methicillin resistant staphylococcus aureus (MRSA) infections and streptococcus viridans. On this basis, we recommend careful selection of antibiotic therapy in obese patients, rather than empirical therapy, which can be especially important if there is no growth in an infected THA. In addition, a preoperative discussion regarding dental prophylaxis against streptococcus viridans may be warranted.
Three distal femoral axes have been described to aid in alignment of the femoral component; the Trans Epicondylar Axis (TEA), the Posterior Condylar Axis (PCA) and the Antero Posterior (AP) axis. Our aim was to identify if there was a reproducible relationship between the axes. Hopefully this will aid the surgeon to more accurately judge the rotation of the femoral cutting block by using the axes with the least variation. This is the first study compare all three distal femoral axes with each other using magnetic resonance imaging (MRI) in a Caucasian population awaiting total knee arthroplasty (TKA). We identified the relationship between these axes by performing MRI scans on 89 patients awaiting TKA with patient-specific instrumentation. Measurements were taken by two observers. Patients had a mean age of 62.5 years (range 32–91). 51 patients were female. The mean angle between the TEA and AP axis was 92.78°, standard deviation (SD) 2.51° (range 88°–99°). The mean angle between the AP axis and PCA was 95.43°, SD 2.75° (range 85°–105°). The mean angle between the TEA and PCA was 2.78°, SD 1.91° (range 0°–10°). We conclude that while there is a reproducible relationship between the differing femoral axes, there is a significant range in the relationship between the femoral axes. This range may lead to greater inaccuracy than has previously been appreciated when defining the rotation of the femoral component. There is most variation between the PCA and the AP axis. Most systems have a cutting block with 3° of external rotation from the PCA and this would be parallel to the TEA in the majority, but not all, cases in this series. This data suggests that if the surgeon is to pick two axes to reference from, one should include the TEA.
Primary bony tumours of the elbow account for approximately 1% of all osseous tumours. The delayed diagnosis is commonly reported in the literature as a result of lack of clinician familiarity. We present the largest series of primary bone tumours of the elbow in the English literature. We sought to identify characteristics specific to primary elbow tumours and compare these to the current literature. We discuss cases of misdiagnosis and reasons for any delay in diagnosis. The authors also recommend a collaborative protocol for the diagnosis and management of these rare tumours. A prospectively collected national database of all bone tumours is maintained by an independent clerk. The registry and case notes were retrospectively reviewed from January 1954 until June 2013. Eighty cases of primary osseous elbow tumours were studied. Tumours were classified as benign or malignant and then graded according to the Enneking spectrum. There were no benign latent cases in this series. All cases in this series required surgical intervention. These cases presented with persistent rest pain, with or without swelling. The distal humerus was responsible for the majority and most aggressive of cases. The multidisciplinary approach at a specialist centre is integral to management. Misdiagnosis was evident in 12.5 % of all cases. Malignant tumours carried a 5-year mortality of 61%. Benign tumours exhibited a 19% recurrence rate and in particular, giant cell tumour was very aggressive. The evolution in treatment modalities has clearly benefited patients. Clinicians should be aware that elbow tumours can be initially misdiagnosed as soft tissue injuries or cysts. The suspicion of a tumour should be raised in the patient with unremitting, unexplained non-mechanical bony elbow pain. We suggest an investigatory and treatment protocol to avoid a delay to diagnosis. With high rates of local recurrence, we recommend regular postoperative reviews.
Aluminia ceramic on ceramic (COC) bearing surfaces have been used for 35 years in total hip arthroplasty (THA). Studies report 85% survival at a minimum follow-up of 18.5 years. Nonetheless, an audible noise is a finding associated with COC bearings with incidence rates of 2–10%. This study aims to determine the prevalence of noise and evaluate its effect on patients. All patients who had a COC THA from August 2003 to December 2010 were contacted and asked to complete a standardised questionnaire. This asked about the presence and characteristics of a noise and if associated with activities, pain and whether this phenomenon should be mentioned preoperatively. Four consultant surgeons performed 282 consecutive primary COC THAs in 258 patients. (Male=122, Female=136 mean age 68.5; age range 28–88). In all cases, the same brand of ceramic acetabular component and stems were implanted. 11.0% had a noise, of which 5.5% had a squeak. Pain was experienced in 38.7% of patients in hips that made a noise. There was no trauma and one dislocation in this group. In this study, 85% of noises occur during weight-bearing although no patients have reduced daily activities as a result of the noises. Of all the patients, 55.0% stated they would have preferred to have known about a noisy hip possibility before consenting but none would have refused consent. Squeaking has not been a problem here despite the prevalence being higher than most in the literature. The authors recommend that squeaking should be discussed preoperatively. A checklist for Orthopaedic Trainees is being drafted to enable trainees to counsel patients appropriately, allowing patients a better opportunity to give informed consent.
It is not often that the patient, surgeon and hospital management are happy about the same service. However, day-case surgery is an exception, as it has well recognised cost-effectiveness. The new day-surgical shoulder arthroscopy service was audited from its commencement in August 2008 until April 2010. The objectives were to see if patients were going home the same day. All data was gathered retrospectively via the hospital's online database and the patients' notes were collected. An Excel database was created. From August 2008 to April 2010, a total of 41 arthroscopies were performed on 41 patients. Consultant K.A. was the operator in each case. In all cases, an interscalene nerve block was attempted by a consultant anaesthetist. All patients received endotracheal intubation and they were placed in a ‘beach-chair’ position. 49% of patients were male and 51% female. Age range was from 17-70 and the average age was 51 years. 66% underwent a sub-acromial decompression and the remainder had a cuff repair. There were two unplanned admissions due to an ineffective interscalene nerve block and the other patient suffered from paranoid schizophrenia and his carer was unavailable. All patients that went home did not re-attend as an emergency. There were no adverse events documented. After discussion with senior staff, we conclude that this service is working well. Key facets of this service are that it should be consultant led with a familiar team, adhere to the standard day-surgical criteria and use interscalene nerve analgesia. The use of continuous regional anaesthetic infusion pumps may improve patient comfort, as reports suggest that they have some advantages. This service shall be re-audited in 2 years time.