Introduction

Motion analysis is a validated method of assessing technical dexterity within surgical skills centers. A more accessible and cost-effective method of skills assessment is to use a global rating scale (GRS). We aimed to perform a validation experiment to compare an arthroscopic GRS against motion analysis for monitoring orthopaedic trainees learning simulated arthroscopic meniscal repairs.

Large studies have reported high dislocation rates (7 to 24%) following revision total hip arthroplasty (THA), particularly when the revision is undertaken in the presence of pre-existing instability. We retrospectively reviewed the clinical and radiographic outcome of 155 consecutive revision THA's that had been performed using an unconstrained dual-mobility acetabular implant. It features a mobile polyethylene liner articulating with both the prosthesis head and a metal acetabular cup, such that the liner acts as the femoral head in extreme positions. It can be implanted in either a press fit or cemented manner. Mean follow-up was 40 months (18–66) and average age 77 (42–89). Uncemented (n=122) and cemented (n=33) implants with a reinforcing cage, were used. Indications were aseptic loosening (n=113), recurrent instability (n=29), periprosthetic fracture (n=11) and sepsis (n=2). Three of the 155 cases (1.9%) dislocated within 6 weeks of surgery and were successfully managed with closed reduction. The 3 dislocations occurred in the groups revised for recurrent dislocation and periprosthetic fracture. There were no cases of recurrent dislocation and no revisions for implant failure. Despite a pantheon of options available, post-operative dislocation remains a challenge especially in patients with risk factors for instability. The use of large diameter heads is proven to improve stability but there are concerns regarding wear rates, metal toxicity and recurrent dislocation in the presence of abductor dysfunction. With constrained liners there are concerns regarding device failure and aseptic loosening due to implant overload. Our dislocation rates of 1.9% and survivorship to date compare favourably with alternative techniques and are also in line with studies from France using implants of a similar design. In our hands, where there are risk factors for dislocation, the use of a dual-mobility implant has been very effective at both restoring and maintaining stability in patients undergoing revision THA.

Background: Our multi-centre international randomized controlled trial compared the one-year incidence of dislocation between a 36 mm and 28 mm metal on highly cross-linked polyethylene articulation in primary and revision total hip replacement (THR).

Patients: 644 patients were entered into the study. Surgical approach was posterior in primary THR and posterior, transfemoral or transtrochanteric in revision THR. Patients were stratified according to a number of factors which may influence dislocation risk and polyethylene wear. Patients were randomized intra-operatively to either a 28 or 36 mm articulation.

Results: The 12-month incidence of dislocation was statistically significantly lower in patients undergoing THR with a 36 mm articulation than in those with a 28 mm articulation (1.3% vs 5.4%, p=.004). When primary and revision THR were examined separately, the 12-month incidence of dislocation was statistically significantly lower in patients undergoing primary THR with a 36 mm articulation than in those with a 28 mm articulation (0.8% vs 4.4%, p=.007). Of the 12 primary THR patients with a 28 mm articulation who dislocated within one year, four experienced recurrent dislocation and two were revised for dislocation. Two patients with a 36 mm articulation dislocated, one of whom experienced recurrent dislocation and was revised. The incidence of dislocation after revision THR with a 36 mm articulation was 4.9%, compared to 12.2% with a 28 mm articulation. Three of the five patients who dislocated following revision THR with a 28 mm articulation experienced recurrent dislocation and were revised within one year of surgery. Two patients dislocated following revision THR with a 36 mm articulation but neither experienced recurrent dislocation or further revision.

This large randomized study unequivocally shows for the first time that, compared to a 28 mm articulation, a 36 mm articulation in THR is efficacious in reducing the incidence of dislocation in the first year following THR.

In revision of cemented femoral components, removal of cement can be challenging. This study evaluates the use of an ultrasonic device (OSCAR, Orthosonics Ltd UK) for cement removal.

30 consecutive patients that attended our outpatients\’ clinic between May 2008 and September 2008, who underwent revision THR by the senior author or his fellows, were retrospectively reviewed. Minimum follow up was 12 months (average 34.9 months).Indications were aseptic loosening and recurrent dislocation. A posterolateral approach was used routinely. Cement was removed with osteotomes and OSCAR. An uncemented modular femoral component was used. At follow-up, radiographs were evaluated for the evidence of extended trochanteric osteotomy (ETO), fracture, cortical perforation, component loosening, migration, and adequacy of cement removal.

None of the cases required an ETO or cortical windowing. In 5 cases prophylactic cabling of the proximal femur was performed. There was one intraoperative femoral shaft fracture (3.33%). There was incomplete cement removal in 7 cases. There was no cortical perforation and no postoperative fracture. There was no case with loosening or migration of the implant.

In all cases that OSCAR was used ETO and cortical windowing were avoided. At an average 34.9 month follow up there was no evidence of thermal tissue damage. In the cases that cement was retained in the canal, this did not affect the stability of the implant. The fracture and the incomplete cement removal were in cases performed by a fellow illustrating the learning curve of the technique.

Aim: To evaluate the possible increase to surgical/operating room capacity by increasing the percentage of uncemented total hip replacement

Introduction: Globally there is growing demand for increased efficiency and productivity from medical care. In hip arthroplasty there has been increased interest in the use of uncemented components with several studies and registry data showing them to perform well clinically 1, 2. One concern with their increased use has been increased costs 3. We have examined the issue of operative timing and discuss the possible role these components may have in increasing theatre utilisation times and so offsetting their cost.

Methods: This was a prospective, cohort study of every hip replacement performed in a dedicated arthroplasty unit within a district general hospital over one year. All care of patients was standardised using pathways, including all surgeons using a posterior approach with posterior repair. This allowed us to determine the relative effect of prosthesis type on quality, safety and efficiency. Demographic, anaesthetic, operative and timing details on all cases performed were collected prospectively and independently of the surgical team. Patients were reviewed at six weeks and one year post op. All readmissions to any hospital were noted and any further surgery recorded.

Results: There were 1248 cases performed in one year. Of these 194 were uncemented (both components) and 286 cemented total hip replacements. Patient demographics were similar (mean age 70.9 years, range 28–92). Both hip types showed no difference in quality or safety factors as assessed by hip scores, patient mobilisation times, complication rates or revision rates. The only difference was in the surgical times. These were (in minutes):

– Mean Standard Deviation Minimum Maximum

(*p< 0.0005)

Conclusions: Our data demonstrates an average time saving of 17 minutes per case performed. If, over the next year, we converted to all uncemented hips we would release 136 hours of operative time, giving an opportunity to get 100 more cases done. This represents a 20% increase in productivity with no compromise to safety or quality.

Early revision is an important risk factor for repeated revision and poor results after primary total hip replacement and instability is a major cause of early revision. Larger articulations with cross-linked polyethylene are proposed as a solution, but these are not without risk, including fracture of the thin polyethylene rim of the liner. The aim of our study was to examine implant-related revisions among primary total hip replacement patients with up to six year follow-up in a randomized controlled trial which compared 28 mm and 36 mm metal on highly cross-linked polyethylene articulations in total hip replacement.

557 patients undergoing primary total hip replacement were included in this study. Risk factors for dislocation and wear were controlled by stratification and patients were then randomized intra-operatively to either a 28 or 36 mm articulation.

To date, 10 hips have been revised for implant-related problems following primary total hip replacement. Seven hips with a 28 mm articulation were revised to a larger articulation because of instability. Four of these were for recurrent dislocation, one for an irreduceable first dislocation and two for subluxation. In contrast, only one patient who had undergone total hip replacement with a 36 mm articulation was revised for recurrent dislocation. One hip with a 36 mm articulation in a well-positioned cup was revised to a 32 mm articulation because of elevated lip liner fracture. Another 36 mm articulation hip was revised for acetabular component loosening.

This study shows that a 36 mm metal on highly cross-linked polyethylene articulation reduces the need for early revision for instability after primary total hip replacement. However, these benefits need to be weighed against the potential risks associated with these articulations, including rare fracture of the relatively thin poly-ethylene liner.

Large articulations using cross-linked polyethylene and other alternate bearings are increasingly being used to reduce the incidence of dislocation, the most common early complication following total hip replacement. While indirect evidence has suggested the potential benefits of a large articulation in reducing dislocation risk, this has not been proven in a well-controlled clinical trial. The primary objective of our multi-centre international randomized controlled trial was to compare the one-year incidence of dislocation between a 36 mm and 28 mm metal on highly cross-linked polyethylene articulation in primary and revision total hip replacement.

644 patients were entered into the study. Patients were stratified according to a number of factors which may influence dislocation risk, including primary or revision total hip replacement, age, sex, Charnley grade, diagnosis and stem type. Patients were randomized intra-operatively to either a 28 or 36 mm articulation.

The 12-month incidence of dislocation was statistically significantly lower in patients undergoing total hip replacement with a 36 mm articulation than in those with a 28 mm articulation (1.3% vs 5.2%, p< .05). A total of 6 dislocations occurred in the 4 patients who dislocated with a 36 mm articulation, compared to a total of 36 dislocations in the 17 patients who dislocated with a 28 mm articulation. When primary and revision THR were examined separately, the 12-month incidence of dislocation was statistically significantly lower in patients undergoing primary total hip replacement with a 36 mm articulation than in those with a 28 mm articulation (0.7% vs 4.2%, p< .05). A total of 4 dislocations occurred in two patients with a 36 mm articulation, compared to a total of 19 dislocations in 12 patients with a 28 mm articulation. The incidence of dislocation after revision total hip replacement with a 36 mm articulation was 4.8%, compared to 11.1% with a 28 mm articulation.

This large randomized study unequivocally shows for the first time that, compared to a 28 mm articulation, a 36 mm articulation in total hip replacement is efficacious in reducing the incidence of dislocation in the first year following hip replacement.

Summary: This study of 1000 patients demonstrates how you can dramatically reduce hospital length of stay, improve clinical outcomes, and increase patient satisfaction if a patient-centred pathway approach is adopted.

Introduction: This study evaluates the effect of adopting a patient-centred approach on clinical outcomes, patient satisfaction and operational efficiency. By adopting standardised working practices, dramatic changes can be achieved to reduce patient length of stay (LOS) and consequently surgical capacity.

Methods: We prospectively studied the first 1000 patients who followed the new pathway (549 Total Knee Replacements, 20 Unicondylar Knee Replacements, 384 Total Hip Replacements and 47 Hip resurfacings). The pathway included an enhanced pre-assessment process. Admission dates were mutually agreed and a predicted discharge date of 4 days was provided. All patients attended a pre-operative education session. Patients were admitted on the day of surgery and followed an intensive physiotherapy program. The surgeons, surgical techniques, and discharge criteria all remained unchanged.

Results: The average length of stay was 4.1 days (St Dev 1.8). 80% of patients went home on or before day 4 post-operatively. This was accompanied by a decreased re-admission rate (1.8%), low complication rates for both hip replacement (Dislocation rate = 0.93%) and knee replacement (Knee MUA = 0.87%) and no cases of deep infection. Pre-operative patient reported outcome measures (WOMAC, SF-12 and Oxford) all improved post-operatively (P< 0.0001) and qualitative data from patients was extremely positive towards the new pathway.

Discussion: The decrease in LOS was dramatic and highly clinically significant. The mean LOS for patients prior to commencing this new pathway was 7.5 days (St Dev 5.7). High patient satisfaction rates indicate that by adopting a patient-centred approach, significant decreases to LOS can be achieved alongside improving the quality of care with a low complication and readmission rate.

The aim of our study was to determine if the canal flare index of the proximal femur is a dependent factor in prosthetic failure after Austin Moore hemiarthroplasty.

We measured the canal flare index on A-P hip X-rays of 100 and 100 patients with failed and successful Austin Moore hemiarthroplasty respectively. We also measured the canal flare index of a control group of 100 patients without hip fractures. The canal flare index (CFI) is defined as the ratio of the width of the femoral canal at two levels: 20mm proximal to the centre of the lesser trochanter and the canal isthmus. Overall we reviewed 300 radiographs. The study group consisted of 68 males and 232 females. In the failed Austin Moore group there were 62 patients (62%) with loosening, 28 patients (28%) with dislocations and 10 patients (10%) with periprosthetic fractures. The canal flare index of the proximal femur was significantly higher in patients who had persistent thigh pain with radiological loosening in comparison the successful and control groups. (3.3 vs 2.6; 3.2 vs 2.7 respectively: p< 0.001). On the other hand patients with periprosthetic fractures had a lower canal flare index in comparison with the successful and control groups (2.1 vs 2.6; 2.1 vs 2.7 respectively: p< 0.001). However there was no differences in the CFI of patients with dislocations compared with successful (2.4 vs 2.6;p=0.1) and control groups (2.4 vs 2.7;p=0.2). This remained the same when controlled for age and sex in a logistic regression analysis.

Conclusion: The CFI can identify patients prone to persistent thigh pain who present as radiological loosening and to periprosthetic fractures and an alternative cemented prosthesis should be considered in this group of patients

Hip Resurfacing is now an established treatment option for young active patients with osteoarthritis. However, there is slow uptake of hip resurfacing by some surgeons, with concern regarding failure from femoral neck fracture, a small but significant risk. Femoral neck fracture may follow notching of the neck, which occurs upon preparing the femoral head after inserting the femoral head/neck guide-wire. The placement of the femoral head/neck guide-wire is a concern for even experienced surgeons routinely, and in difficult cases of femoral head/neck deformity this is especially so.

For the first time a preliminary series of Durom hip resurfacings, based on the successful Metasul bearing, were implanted using a computer image guidance system. The aim of computer navigation is to optimally place the femoral prosthesis in the correct degree of valgus with good underlying bone coverage, without notching the femoral neck or over-sizing the femoral component. Preoperative CT scanning was not required. A standard posterior approach to the hip was utilised, and a navigation reference frame was applied to the proximal femur. Then using an image intensifier and the computer navigation system, a guide-wire was passed quickly and easily into the femoral head/neck with a navigated drill guide. The femoral head was then prepared safely for the femoral component of the resurfacing, with minimal risk of femoral neck fracture.

Computer navigation systems have an important role to play in hip resurfacing with respect to femoral head/neck preparation, as demonstrated from our preliminary study. This series shows the use of computer navigation in hip resurfacing to be both SAFE and SIMPLE with a quick learning curve. It was shown to be FASTER and MORE ACCURATE in the process of guide-wire placement in the femoral head/neck as compared to conventional jigs. Crucially, femoral neck fractures may even be potentially ELIMINATED using this technique.

In the future, hip resurfacing in conjunction with computer navigation systems may allow;

- SAFER hip resurfacing, with reduced rates of femoral neck fractures

This paper describes the design, development and early surgical experience with a stereotactic device to allow closed retrieval and interchange of intramedullary rods in children with osteogenesis imperfecta. This relatively atraumatic procedure may allow more frequent rod interchange than with other techniques, lessening the likelihood of deformity and fracture in the unsupported skeleton when the bone has outgrown the intramedullary rod. The procedure was developed by design studies in vitro followed by intramedullary rodding of tibiae of New Zealand white rabbits. It has been used in children 12 times, in six tibiae and six femora: 11 rods have been successfully retrieved, with rod interchange in eight of these cases.

Three cases of severe osteogenesis imperfecta are reported. Each was treated by closed intramedullary rodding, combined with osteoclasis to correct deformity. Operation was performed within a few months of birth. Both tibiae and both femora were stabilised in one operation, using x-ray image intensification to monitor placement of the rods. The technique used to insert the rods is described. The procedure appeared to be entirely satisfactory in reducing the incidence of fractures and it allowed the affected infants to be handled much more easily.

Cubitus varus is the most common complication of supracondylar fracture of the humerus in children. Although function of the elbow is not greatly impaired, the deformity is unsightly. It usually results from malunion, since growth disturbance of the humerus after this fracture is uncommon. The normal carrying angle can be restored by supracondylar osteotomy. This operation was done in 32 patients over a ten-year period, 16 of them using the technique described by French (1959). The results in 27 patients are reviewed in the light of previous reports. French's method proved safe and satisfactory.