Background

Dual compartment knee replacement has been introduced to allow sparing of the cruciate ligaments and lateral compartment and preserve some biomechanics of knee function.

NICE guidelines state patients undergoing elective TKR receive post-operative chemical prophylaxis unless contraindicated, following guideline implementation our aim was to determine VTE incidence and wound complication outcomes related to administration of Rivaroxaban or Enoxaparin.

From April to October 2010 we prospectively studied 294 patients having primary or revision TKR. Each received either Rivaroxoban (n=219), Enoxaparin (n=68), UHF 5000 units (n=4) or no thromboprohylaxis (n=3) post-operatively. Primary outcome was identification of symptomatic post-operative VTE incidence and compared incidence over the same period in 2009 when aspirin was the standard chemical prophylaxis for VTE. Secondary outcomes were prolonged wound oozing rates and wound washout.

VTE occurred in 3 of 219 patients (2 PE, 1 DVT) receiving Rivaroxaban, and 1 PE in a patient who did not receive any thromboprophylaxis. No patients prescribed Enoxaparin developed VTE. In the same period 2009 there were 21 confirmed PEs in 512 patients undergoing TKR. This was statistically significant (Chi squared test p=0.02).

Prolonged oozing was noted in 3 patients receiving Enoxaparin, and 17 patients receiving Rivaroxaban. 6 patients treated with Rivaroxaban returned to theatre, 3 for continuous ooze, 2 for wound dehiscence and 1 for infection. During the same period in 2009, there was only 1 return to theatre for haematoma washout. (Chi squared test; p=0.02).

Following the NICE guidelines, there is a reduction in the PE rate following TKR but there is an increase in the overall return to theatre rate.

Involvement of Patellofemoral joint (PFJ) has significant bearing in the management of osteoarthritis of the knee. The aim of this study is to assess the relationship between skyline radiographs, MRI and arthroscopic findings in the patellofemoral joint.

Data was collected prospectively from fifty-three patients who underwent arthroscopy. There were 36 males and 17 females in the group with mean age of 48 years (range 18-71). Arthroscopically PFJ arthritis was classified based on Outerbridge grading system. Patients with Outerbridge grade III and IV lesions were considered to have significant arthritis of the PFJ. Kellgren-Lawrence grading system was used to assess the skyline radiographs. Radiographically patients with grade III and IV Kelgren-Lawrence changes were considered to have significant osteoarthritis of the PFJ. MRI scans were also studied to assess involvement of PFJ. Thirty-two patients had MRI scan and 20 patients had skyline views done as part of preoperative work up. Arthroscopic findings were considered as gold standard.

MRI scan had specificity of 75%, sensitivity of 81%, positive predictive value of (PPV) 77 and negative predictive value of (NPV) 80% in diagnosing significant PFJ arthritis. Skyline radiographs had specificity of 100%, sensitivity of 50%, PPV of 100% and NPV of 57%. The overall accuracy of skyline radiographs in predicting significant PFJ arthritis was 70% and for MRI was 78%. We conclude that skyline radiographs has some value in he diagnosis of PFJ arthritis, however the sensitivity and negative predictive value is very is poor.

Between December 2004 and June 2006, 136 patients (156 total hip replacements), were sent from the waiting list of the Cardiff Vale NHS Trust to the NHS Treatment Centre, Weston-super-Mare, in an attempt to reduce the waiting time for total hip replacement. Because of concerns about their outcome, each patient was contacted and invited to attend a review appointment with a consultant specialising in hip and revision hip replacement.

A total of 98 patients (113 hips) were reviewed after a mean of 23 months (11 to 30). There were 104 cemented hips, seven hybrid and two cementless. An acetabular inclination of > 55° was seen in 18 (16%). Radiolucent lines around the acetabular component were seen in 76 (67%). The femoral component was in more than 4° of varus in 47 (42%). The medial floor had been breached in 13 (12%) and there was a leg-length discrepancy of more than 1 cm in ten (9%). There were three dislocations, one femoral fracture, one pulmonary embolus, one deep infection and two superficial wound infections.

To date, 13% (15 hips) have been revised and a further 4% (five hips) await revision, mostly for a painful loose acetabular component. The revision rate far exceeds the 0.5% five-year failure rate reported in the Swedish Registry for the components used. This initiative and the consequent need for correction of the problems created, has significantly increased the workload of our unit.

144 total hip replacements were performed by Swedish Orthopaedic Surgeons at Weston NHS Treatment Centre between 2004–2006, in an attempt to reduce the waiting list in Cardiff. Following concerns regarding the outcome of knee arthroplasty patients, the Welsh Assembly funded a clinical and radiographic review of all hip arthroplasty patients from the same unit.

100 hips were reviewed at a mean follow-up of 24 months. The mean Oxford Hip Score was 30 (range 12–60).

Radiolucencies were seen in acetabular zone 1 in 34, and all 3 zones in 28 hips. Femoral component position was > 4 degrees varus in 41 cases. Medial floor breach with intrapelvic cement was seen in 12 cases. 10 cases had > 1cm leg length discrepancy. There were 3 early dislocations, 1 intraoperative distal femoral fracture, 1 Pulmonary Embolus and 2 superficial infections.

4 patients have received further treatment so far, and 12 have been listed for acetabular component revision for loosening. 1 has been listed for stem revision for symptomatic leg length discrepancy of 2.5cm.

There is an unacceptably high early failure rate in this group of patients. The cost of further investigation and revision surgery far outweighs cost-savings achieved by outsourcing treatment to a distant centre.

Introduction: A composite femoral stem was introduced with a structural stiffness similar to that of the native femur to promote proximal load transfer. This consisted of a cobalt-chromium alloy core surrounded by an injection-moulded layer of polyaryletherketone covered with a porous titanium mesh.

Materials and Method : 31 primary total hip replacement stems were implanted in 26 patients with an average age of 37 years (range 17–57) using the Epoch Stem (Zimmer, Warsaw, IN) as part of a prospective multicentre trial. A cementless Harris-Galante I acetabular component with a 28mm polyethylene insert was used in 28 cases, a Plasma cup (Aesculap) in 1 case and a bipolar head in 2 cases. Annual follow-up using Harris Hip Scores and radiographic evaluation was performed for a mean of 10.1 years.

Results: Harris Hip Scores improved from a mean of 56 points preoperatively to 90 at the time of last follow-up. Radiographs showed no stem migration or loosening. 4 cases with polyethylene wear showed trochanteric osteolysis. Specific radiographic features noted were calcar rounding in 10 cases and improvement in calcar appearance with squaring in 4 cases. Calcar resorption was seen in 1 case associated with polyethylene wear. There have been 9 instances of revision of the head or acetabular component – 3 liner exchanges for polyethylene wear, 3 liner exchanges for dissociation, 1 acetabular component revision for infection and 2 bipolar heads revised to unipolar heads with cementless acetabular component for pain. No stem has required or requires revision.

Discussion: The Epoch stem resulted in an excellent clinical outcome, with evidence of radiographic stability and proximal bone preservation, and no cases of stem revision in a small cohort of young patients at 10-year follow-up. The limitation of reconstruction in this cohort of young patients has been the acetabular component.

Introduction: Image Intensifier screening is commonly utilised in orthopaedic theatres. There has been concern regarding the cumulative radiation dose to surgeons and theatre personnel. The mini C-arm intensifier has been reported to scatter less radiation and have a reduced radiation dose to patient and theatre staff.

Material and Methods: 2 month prospective survey of usage of radiographer-operated large intensifier and surgeon-operated mini C-arm image intensifier in a district general hospital orthopaedic theatre department.

Results: 153 cases required image intensifier screening. 63% used the large intensifier and 37% the mini c-arm intensifier. The complication rate for the large intensifier was 16%. There were delays in 11% of cases using the large intensifier. The total radiographer attendance time was 123 hours. For the mini C-arm intensifier there were no complications or delays. The minimum radiographer time saved by using this machine was 21.9 hours.

Conclusion: The mini C-arm intensifier has saved 15% of the radiographer workload with its current pattern of usage in our department. There have been no complications or delays as a result of its usage in theatres. Other departments are encouraged to consider acquisition of such a machine to facilitate theatre throughput and reduce demands on the radiology department.

Dissociation of the polyethylene liner of modular acetabular components is a rare occurrence, and previous reports have commented on the difficulty in diagnosis from plain radiographs. The radiograph is often incorrectly reported by radiologists as showing advanced polyethylene wear, causing delay in referral and increasing the complexity of treatment required.

We report 9 cases of late polyethylene liner dissociation of the cementless Harris-Galante II porous-coated acetabular component (Zimmer Inc, Warsaw, IN) which occurred without trauma or injury. This is the largest reported series to date.

In all cases, there was a common pattern of clinical symptoms and signs which is described.

Radiographs showed a distinct appearance with a radiolucency medial to the femoral neck in association with an eccentrically placed femoral head lying in contact with the acetabular metal shell. We have termed this the ‘crescent sign’.

We believe that the diagnosis can be made from a single antero-posterior pelvic radiograph without the need for previous films for comparison, or the need for arthrography. Clinicians should look specifically for the crescent sign when an eccentrically placed femoral head has been noted, in order to differentiate the more unusual diagnosis of dissociation from that of polyethylene wear. Early diagnosis and prompt referral prevents further damage to the femoral head and metal acetabular shell, thus reducing the complexity of revision surgery.

There is a strong drive from industry, patients and the media to offer minimal access hip surgery (MAS) for joint arthroplasty. There is a plethora of definitions, implants, specialist instrumentation and techniques available. Confusion reigns as to the definition, who should offer it, which approach should be used, and what training should be undertaken.

Method : All Consultant Orthopaedic Surgeons in the United Kingdom were sent a simple questionnaire asking for MAS training undertaken, evidence of specialisation, volume of minimal access cases performed, availability of specialist instrumentation, approach used and definition of mimimal access surgery.

Results : 23% of those performing hip arthroplasty had performed MAS. The majority performed between 1–5 cases last year. 41% had observed MAS.

Of those with a specialist interest in hip arthroplasty, 37% had performed MAS.

Of those performing MAS, 83% had observed another surgeon and 60% had attended a course. 29% of consultants intend to perform MAS in the future. The mean and mode quoted length of a regular total hip arthroplasty scar was 15.4 and 15cm respectively. The mean and mode quoted length of a MAS scar was 9.7 and 10 cm respectively.

75% used the miniposterior approach.

Relationships with specialisation, British Hip Society membership and volume breakdown are discussed.

Conclusion: MAS is a popular technique although currently small case numbers are being performed. Given the level of interest in the technique, the definition and training required need to be clarified, and the clinical outcome requires close monitoring to ensure that standards of implantation are not jeopardised.

There has been a rapid uptake in the use of Resurfacing Hip Replacement (RHR) in the United Kingdom, and its use is likely to accelerate both in Europe and the USA. The current level of use of RHR is not accurately known.

It was decided to audit the use of RHR amongst Consultant Orthopaedic Surgeons in the United Kingdom, and to identify the number of operations performed in the last twelve month period, and the specific training undertaken before offering this procedure.

A questionnaire was sent to 1600 Consultant Orthopaedic Surgeons with 894 responding.

19% had performed RHR in the previous year.

Excluding surgeons that do not perform Total Hip Replacement, 23.5% of surgeons had performed RHR.

29.5% of all orthopaedic surgeons had observed RHR surgery and 23% had been on an RHR course. 65% of all consultants who had attended a course were offering RHR surgery.

7.8% of those performing RHR had neither been on a course nor observed surgery.

There was no relationship between years in practice and RHR surgery.

There was a weak association with British Hip Society membership and with a previous fellowship in Hip Surgery.

Of those performing RHR, 72% perform less than 20 cases per year. The majority of surgeons perform 6-10 RHRs per year.

Although interest in RHR is increasing, it is currently performed by the minority of consultants. Given the steep learning curve, the lack of knowledge of long-term survival, and concerns regarding metal on metal bearing surfaces, RHR should be used by surgeons with a specialist interest in hip arthroplasty. We believe RHR should be used in accordance with the guidance given by the National Institute for Clinical Excellence.

Nine patients underwent arthrodesis of the knee using a customised coupled nail (the Mayday arthrodesis nail), five after infected arthroplasty, one following failed arthrodesis, one for intractable anterior knee pain, one for Charcot instability and one after trauma. Comparison was made with 17 arthrodeses, eight undertaken using external fixation, four with dual compression plates, and five with long Küntscher nails. Union was achieved in all patients (100%) at a mean time of ten months using the customised implant. There were no complications despite early weight-bearing. No further procedures were required. This contrasted with a rate of union of 53% and a complication rate of 76% with alternative techniques. Of this second group, 76% required a further operative procedure.

We compared the Mayday arthrodesis nail with other techniques of arthrodesis of the knee. The differences in the need for further surgery and occurrence of complications were statistically significant (p < 0.001), and differences in the rate of nonunion and inpatient stay of less than three weeks were also significant (p < 0.05) using Fisher’s exact test.

We conclude that a customised coupled intramedullary nail can give excellent stability allowing early weight-bearing, and results in a high rate of union with minimal postoperative complications.

The aim of this study was to demonstrate the effectiveness of a customised coupled arthrodesis nail.

Knee arthrodesis is now infrequently performed and is usually reserved as a salvage for infected Joint arthroplasty or occasionally for intractable pain. Many methods have been used. Recently locked intramedullary coupled nails have gained in popularity. To deal with all size combinations a large inventory is required. We wish to report our series using a customised implant and to compare the outcome with other methods of knee arthrodesis.

Nine patients underwent arthrodesis using this implant, six following infected arthroplasty, two for intractable anterior knee pain and following trauma. Comparison was made with 17 arthrodeses performed since 1993 using external fixation (8), plates (4), and long K-nails (5). Union was achieved in nine patients (100%) at a mean time of 10 months using the customised implant. There were no complications despite early weight-bearing. No further procedures were required. This contrasted with a union rate of 65% with a 76% complication rate using alternative techniques. Seventy six percent of this second group required a further operative procedure.

We conclude that a customised coupled intramedullary nail can give excellent stability allowing early weight-bearing, and results in a high union rate with minimal post-operative complications. The differences in need for further surgery and occurrence of complications were statistically significant (p< 0.001), and differences in in-patient stay and non-union rate were also significant (p< 0.05) using Fisher’s exact test.