Aims

The aim of this study was to compare the osseous reactions elicited by all-suture, polyetheretherketone (PEEK), and two different biodegradable anchors used during rotator cuff repair.

Introduction

Previous hemodynamics studies in shoulder arthroplasty only evaluated Western population and mainly focused on risk factors of transfusion. However, Asians are relatively small, and have higher bleeding risk due to prothrombin-clotting-factor polymorphisms. Therefore, it is not appropriate to apply the results of previously studies directly to Asians. Authors compare different hemodynamics depending on the types of shoulder arthroplasties, and evaluate predictors for transfusion in Asian population.

Introduction & Background

Clinical outcome after reverse total shoulder arthroplasty (RTSA) can be influenced by technical and implant-related factors, so the purpose of this study was to investigate whether individualizing humeral retroversion and subscapularis repair affect the clinical outcomes after RTSA.

We examined data from a large prospectively collected dataset which followed up patients after Exeter total hip replacement (THR) - the Exeter Primary Outcome Study. We studied 78 patients who had total hip replacement for osteoarthritis on a morphologically normal hip, and in whom the other hip was also morphologically normal for comparison. All selected patients had complete patient outcome data at 1 and 5 years, and x-rays at 1 year were available.

We measured accuracy of reconstruction on AP Pelvis radiographs. The parameters measured were difference in height of lesser trochanter from horizontal pelvic line (LLD); length from ASIS to greater trochanter (indicating abductor length, AL); length from symphysis to centre of femoral head (SFH); length from centre of head to axis of femur (offset). We examined clinical outcomes including gain of Oxford Hip Score (DOHS) at 1 and 5 years, absolute OHS at 1 and 5 years, and absolute SF-36 Physical Functioning and Role Physical scores at 1 and 5 years.

Examining the ratios of AL, SFH, Offset, Offset to SFH ratio and LLD between side of THR and unaffected side all showed marked variation. Thus the ratio of SFH varied from 0.85 to 1.11. For further analysis we divided the patients into 3 groups on the basis of variability of the ratio from 1; we examined whether the clinical scores above varied between these 3 groups. 1 way ANOVA demonstrated no significant difference for any of the clinical outcomes for any of the 5 grouped x-ray variables.

Accuracy of reconstruction has been shown to affect the risk of dislocation after THR. Our results indicate that clinical outcomes of total hip replacement appear resilient to some degree of surgical inaccuracy. Future trials of navigation should be designed to demonstrate not only improved accuracy but also improved clinical outcome.

The aim of most new implants for cervical disc replacement is to maintain or restore function. The Dynamic Cervical Implant (DCI(tm), Paradigm Spine) aims at combining the advantages of the gold standard fusion technique with the motion preservation philosophy. DCI has a limited motion: it works like a shock absorbing spring and may help to slow down adjacent segment degeneration.

Between 2007 and 2009 we selected 79 patients aged 32 to 73 years for treatment with DCI at either one or two levels (10 patients). Indications were radiculopathies (n=45), axial pain (n=4) or spondylotic spinal stenosis (n=30) with out chronic myelopathy. Patients are followed up at 3, 6, and 12 months after surgery.

Disc surgery was performed at C3/C4 (n=2), C4/5 (n=6), at C5/6 (n=43), C6/7 (n=37) and at C7/T1 (n=1). In flexion/extension radiographs motion rapidly increased after surgery. However, 5 of 19 treated levels were fused (seen at 6 or 12 months). After implant footprint was changed and larger sizes were provided only 2 of 67 segments fused. Still 96% of the patients rated their clinical result as excellent or good. There were no implant related complications or revision surgery.

Disc replacement with DCI is a new strategy that is positioned in between anterior cervical fusion and disc prosthesis. Clinical results are as good as in anterior cervical fusion. Adjacent segment protection must be judged in future follow-ups. We were able to show that the change of implant footprint has significantly reduced fusion rate.

Aim

The aim of our study was to assess lateral tracking of the patella with differing designs of Total Knee Arthroplasty (TKA) and compare to that of the native patella.

Introduction: More than 140,000 joint replacements are carried out in England and Wales per annum costing from £4000 to £7000 each (1, 2). Implant costs are relatively fixed but there are considerable variations in length of stay [LOS] following surgery. The National Audit office estimated that a reduction of two days per patient could save the NHS £15.5 million per year (2).

A specialist orthopaedic ward for elective arthroplasty was opened in Bangor in 2008 in an attempt to address these issues. The staff per bed ratio remained the same as in the general orthopaedic wards but beds were “ring fenced” and strict infection control measures protocols were implemented. This audit aimed to assess the effect of the specialist ward on LOS following arthroplasty.

Method: Retrospective data on length of stay, demographics and surgical site infections [SSI] were collected for the six months before and six months after the specialist ward was opened. Only primary lower limb arthroplasty data was evaluated and LOS was calculated from day of operation to the day of discharge. Statistical analysis was performed on the length of stay with SPSS software using the two-sample t-test and Mann-Whitley U test.

Results: Patients were managed by the same surgical teams in the same theatres but nursed in different ward settings. Group 1 included 222 patients managed in general orthopaedic wards and group 2 included 191 patients, managed in the ring fenced ward. The mean age for total hip replacements was 70.8 in group 1 and 71.2 years in group 2. The mean age for total knee replacements was 70.9 years in group 1 and 69.2 years in group 2. The overall mean LOS for both procedures was 7.61 days (95% CI: 7.14 – 8.07) in group 1 compared with 5.67 days (95% CI: 5.28 – 6.06) group 2. This was statistically significant (p< 0.001). The mode was 7 days in group 1 compared with 4 days in group 2. Three SSIs were noted in group 1 and zero in group 2.

Conclusions: This audit demonstrates a two day reduction in LOS for patients managed in a ring fenced ward. The reasons for the reduction are multi factorial but include a trend for reduced SSI. Overall reduced stay frees up resources for other use and may reduce costs. Other units may benefit from similar dedicated wards in response to growing demand for arthroplasty within a system of fixed resources.

Introduction: Preoperative planning plays an important role in any surgical procedure and total hip replacement (THR) is no exception. Templating of radiographs allows preoperative assessment of the correct size of implant to be used, lowers the risk of periprosthetic fracture, helps restore femoral offset and leg length, facilitates the optimisation of alignment and ensures the correct implants sizes are available.

With the wide scale use of Picture Archiving and Communication Systems (PACS) in the National Health Service (NHS), the potential exists for faster and more accurate templating of THRs.

Aim: In performing this study, we assessed whether there is adequate provision of the current NHS PACS to allow optimal digital templating for THRs. We also made comparison between the availability and overall ease of conventional versus digital templating.

Methods: Data was collected using a telephone questionnaire requesting information from the on-call orthopaedic Specialist Registrar (SpR) in 28 Greater London and surrounding area NHS Hospitals. Data on the availability of PACS and the ability to template using hard-copy or digital templating was collected and analysed.

Results: PACS were used in all 28 (100%) hospitals that were contacted. None performed conventional templating regularly and only 8 (28.6%) admitted to occasional templating. The predominant reason for this was difficulty in obtaining hard copies of x-rays in 12 (42.9%) hospitals, as well as lack of availability acetate templates, with 13 (46.4%) claiming that this was the case.

Digital templating software was available in 14 (50%) hospitals. Despite this, none of them performed digital templating regularly. In the 50% that did have digital templating, this was not routinely done for the following reasons:

only 3 (10.7%) allowed easy access to the software to the SpRs

Discussion: Digital PACS systems have made great improvement in the access of radiographs in the NHS. With regards to orthopaedic practice, however, we have shown that the benefit of digital templating is being overlooked within the NHS.

Radiographs are frequently ordered following acute knee injury. However, it is suggested that only 6 % of patients with a knee trauma have a fracture. Decision rules such as the Ottawa rules and the Pittsburgh rules have been developed to reduce the unnecessary use of radiographs following knee injury.

We prospectively reviewed all acute knee injury patients who were referred to our clinic from the emergency department over a 3 month period. The reason for ordering radiographs was analysed. The Ottawa and the Pittsburgh rules were applied to individual patients to evaluate the need for radiographs. In patients with a diagnosis of fracture, the accuracy of the Ottawa and the Pittsburgh rules was studied.

A total, of 106 patients were referred to the acute knee clinic from the emergency department. 95.28 % (101) of these patients had radiographs of their knee in the emergency department. Five (4.72%) patients had a fracture of their knee and all these cases, the Ottawa and the Pittsburgh knee rules for ordering radiographs was fulfilled. In a vast majority of cases without any fracture, the clinical reason for ordering radiographs was not clear. Using the Ottawa rules for knee radiography 25.47% (27) radiographs could be avoided without missing a fracture. Using the Pittsburgh rules, 30.19 % (32) knee radiographs could be avoided without missing a fracture.

The Ottawa and the Pittsburgh rules have a high sensitivity for the detection of knee fractures. Use of these rules can aid efficient clinical evaluation of the knee in an emergency situation without adverse clinical outcome. They may also have an implication on reducing the work load of radiology department and reduction of health costs.

Aim: The purpose of this study is to explore the experience of a consultant orthopaedic surgeon, and to quantitatively describe the learning curve for hip arthroscopy.

Introduction: Arthroscopic surgery in orthopaedics is a well established procedure for both diagnostic and therapeutic purposes. Unlike many other joint arthroscopies, hip arthroscopy has been delayed in its development. It was first pioneered by Burman in 1931, who under-took a study on cadavers, stating that ‘it is manifestly impossible to insert a needle between the head of the femur and the acetabulum’. Over several decades, this technique has developed considerably, but still remains a technically demanding and difficult procedure. The learning curve for hip arthroscopy has not previously been objectively quantified.

Method: We prospectively reviewed the first 100 hip arthroscopies performed in the supine position between 1999 and 2004. Surgery was performed by a single experienced hip and knee consultant orthopaedic surgeon (FH). We assessed the operative time (traction time), surgeon comfort, patient satisfaction at 6 months and operative complications. This was analysed for consecutive blocks of 10 cases. Results of the first 10 and the remaining 90 cases, subsequently the first 20 and remaining 80 cases, and finally the first 30 and remaining 70 cases were compared for a difference.

Results: The mean traction time was 55 minutes (range: 36–94 minutes). Mean surgeon comfort was 73% (range: 52–89%). 49% of patients reported an excellent outcome at 6 months follow – up. Only 8% of patients reported an unsatisfactory outcome. The main complications noted were chondral damage (6 cases) and perineal injuries (4 cases). There was a remarkable decrease in complications from the first 30 cases compared to the remaining 70 operations. 5 cases of chondral damage was noted in the first 30 cases, compared to 1 (1.4%) in the remaining 70 cases. The number of perineal injuries was noted to decrease from 3 cases in the first 30 operations to 1 (1.4%) in the subsequent 70 operations.

There is an overall decrease in operative time over the 100 cases, representing a gradual learning process throughout. However, the fall from an average time of 75 minutes for the first 30 cases, to the average operative time of 30 minutes for the remaining 70 cases, is a significant learning process (40% fall in operative time). We thus, believe the learning curve to be 30 operations.

Conclusion: We have demonstrated that there is a considerable fall in operative time when comparing the first 30 cases with the remaining 70 cases. This quantitative decrease is indicative of a rapid learning curve. This is further suggested by the remarkable fall in complications during this learning phase.

Studies have shown that the normal patella tracks laterally with flexion of the knee joint, consistent with the findings of Eckhoff et al. that the femoral sulcus is lateral to the mid-plane between the 2 femoral condyles. Patellar pain and instability is a known complication of Total Knee Arthroplasty (TKA). To date, several studies have identified the effect of femoral and tibial components on complication after TKA. However, there is very little work on how the design of the implant affects patellar tracking. Our study compares lateralization of the patella in two different AP stabilized knee implants.

A modified caliper was used to measure the width and position of the patella relative to the femur at different degrees of knee flexion. The relationship of the patella midpoint to that of the femur was subsequently assessed. Group 1 consisted of 25 native knees. Group 2 consisted of 25 patients with antero-posterior stabilized knee implant with a spherical medial condyle and a deep lateralized patellar groove (MRK, Finsbury Orthopaedics, UK). And Group 3 consisted of 25 patients with traditional cam-and-post posterior cruciate-substituting implant with a symmetrical patellar groove (PFC-Sigma, DePuy, UK). The mean follow-up for the 50 TKAs was 28 months.

Lateral tracking corresponded well in all groups, but the mean lateral displacement of the patella in group 2 correlated more closely to that of group 1. At 90 degrees of flexion, the patella was displaced a mean of 7mm laterally in both groups 1 and 2, but a mean of 4mm in group 3. Two-tailed Mann-Whitney U test (95% confidence interval) showed that the difference in lateral patellar displacement between groups 1 and 3, and that between groups 2 and 3 were statistically significant (p< 0.05). However, the patellar displacement between groups 1 and 2 was not statistically different.

Our results indicate that lateral patellar displacement in group 2 is similar to that of native knees (group 1). The effect of the underlying lateralized deep patellar groove of the femoral component in group 2 is more able to mimic that of the native femoral sulcus. This intrinsic implant design accommodates the natural tracking of the patella.