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.

As part of the national initiative to reduce waiting times for joint replacement surgery in Wales, the Cardiff and Vale NHS Trust referred 224 patients to the NHS Treatment Centre in Weston-Super-Mare for total knee replacement (TKR). A total of 258 Kinemax TKRs were performed between November 2004 and August 2006. Of these, a total of 199 patients (232 TKRs, 90%) have been followed up for five years. This cohort was compared with 258 consecutive TKRs in 250 patients, performed at Cardiff and Vale Orthopaedic Centre (CAVOC) over a similar time period. The five year cumulative survival rate was 80.6% (95% confidence interval (CI) 74.0 to 86.0) in the Weston-Super-Mare cohort and 95.0% (95% CI 90.2 to 98.2) in the CAVOC cohort with revision for any reason as the endpoint. The relative risk for revision at Weston-Super-Mare compared with CAVOC was 3.88 (p < 0.001). For implants surviving five years, the mean Oxford knee scores (OKS) and mean EuroQol (EQ-5D) scores were similar (OKS: Weston-Super-Mare 29 (2 to 47) vs CAVOC 29.8 (3 to 48), p = 0.61; EQ-5D: Weston-Super-Mare 0.53 (-0.38 to 1.00) vs CAVOC 0.55 (-0.32 to 1.00), p = 0.79). Patients with revised TKRs had significantly lower Oxford knee and EQ-5D scores (p < 0.001).

The results show a higher revision rate for patients operated at Weston-Super-Mare Treatment Centre, with a reduction in functional outcome and quality of life after revision. This further confirms that patients moved from one area to another for joint replacement surgery fare poorly.

Recently biodegradable synthetic scaffolds (Trufit plug) have provided novel approach to the management of chondral and osteochondral lesions. The aim of this study was to assess our 2 year experience with the Trufit plug system.

22 patients aged 20 to 50 years old all presenting with knee pain over a 2 year period were diagnosed either by MRI or arthroscopically with an isolated chondral or osteochondral lesion and proceeded to either arthroscopic or mini arthrotomy Trufit plug implantation. In 5 patients plug implantation was undertaken along with ACL reconstruction (3), medial meniscal repair (1) and contralateral knee OCD screw fixation (1). Pre and post operative IKDC scores were obtained to assess change in knee symptoms and function.

At a mean follow up of 15 months (range 2 – 24 months) improved IKDC scores were achieved with the scores improving with time. 2 patients have had a poor result and have had further surgery for their chondral lesions. One patient had failure of graft incorporation at second look arthroscopy and went onto to have a good result after ACI. The second patient had good graft incorporation on second look but had progression of osteoarthritic degeneration throughout the other compartments of the knee which were not initially identified at the time of Trufit plugging.

We conclude that Trufit plug is an alternative method for managing isolated chondral and osteochondral lesions of the knee which avoids harvest site morbidity or the need for staged surgery.

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.

Purpose of the study: The aim of this study was to determine risk factors for clinically relevant pulmonary embolism (PE) in patients undergoing elective knee arthroplasty.

Methods and results: We performed a retrospective analysis of 956 total knee arthroplasties performed at our institution between June 2007 and May 2008 to identify patients with postoperative PE confirmed by computed tomography pulmonary angiogram (CTPA). All patients had received foot pumps, thromboembolism deterrent stockings and 75mg of Aspirin postoperatively. Patients with PE were matched for age, gender, surgeon, date and type of surgery with a control group of 32 patients. Patients case notes were reviewed to identify known risk factors for PE such as age, gender, ASA grade, BMI, medical comorbidities, pre-operative haemoglobin (Hb), postoperative Hb, drop in Hb, day mobilised postoperatively, tourniquet time and temperature in the postoperative period. Statistical analysis was performed using Statistical Package for the Social Sciences version 12.0 (SPSS Inc., Chicago, Illinos).

Twenty one (2.2 %) cases were identified with CTPA confirmed PE. Of the various risk factors studied, delay in postoperative mobilization was the only significant risk factor for PE (p=0.019). None of the other risk factors were significant for PE. Postoperative pain was the commonest reason for delayed mobilisation followed by lower limb paraesthesia from regional nerve blocks.

Conclusion: We found that a delay in postoperative mobilization was the most significant risk factor for clinically relevant PE in our patient population following knee arthroplasty. The use of chemical thromboprophylaxis for all patients undergoing elective knee arthroplasty is currently under debate. Not all patients are at equal risk, however, and chemical prophylaxis is not devoid of complications. Early postoperative mobilization of all patients may help prevent this potentially fatal complication.

We aimed to determine the reliability, accuracy and consequently the clinical role of digital templating in the pre-operative work up for total knee arthroplasty patients.

With the increasing use of digital radiology images, analogue templating may soon be defunct. Digital templating is a more recent development and its role is yet to be determined.

Ten pre-operative digital radiographs were templated by four independent observers. Inter-observer and intra-observer reliability was assessed using the kappa measure of concordance. Subsequently, 40 consecutive total knee arthroplasty patients underwent pre-operative digital templating. This was a blinded process by a consultant surgeon not involved with the operation. Each patient underwent TKR using the PFC Sigma System sized intra-operatively, without the operating surgeon having knowledge of the pre-operative templating result. Comparison was made between the pre-operative digital templates and the blinded intra-operative sizing.

For both the femoral and tibial templating there was good to very good inter- and intra-observer agreement. For the femoral component the templating was correct in 47.5% (± 1 size difference 97.5%). The tibial templating was correct in 55% (± 1 size difference 100%).

The inter- and intra-observer reliability of digital templating process has been shown to be acceptable but the correlation between digital templating and the actual size implanted is poor. Our series shows a similar accuracy to the published data on analogue templating for the same implant. Like analogue templating, its clinical role remains uncertain and its poor correlation to the actual implant sizes limits its usefulness.

We aimed to determine the reliability, accuracy and the clinical role of digital templating in the pre-operative work-up for total knee replacement.

Initially a sample of ten pre-operative digital radiographs were templated by four independent observers to determine the inter- and intra-observer reliability of the process. Digital templating was then performed on the radiographs of 40 consecutive patients undergoing total knee replacement by a consultant surgeon not involved with the operation, who was blinded to the size of the implant inserted. The Press Fit Condylar Sigma Knee system was used in all the patients. The size of the implant as judged by templating was then compared to that of the size used.

Good inter- and intra-observer agreement was demonstrated for both femoral and tibial templating. However, the correct size of the implant was predicted in only 48% of the femoral and 55% of the tibial components. Albeit reproducible, digital templating does not currently predict the correct size of component often enough to be of clinical benefit.

As part of the government’s initiative to reduce waiting times for major joint surgery in Wales, the Cardiff and Vale NHS Trust sent 224 patients (258 knees) to the NHS Treatment Centre in Weston-Super-Mare for total knee replacement. The Kinemax total knee replacement system was used in all cases. The cumulative survival rate at three years was 79.2% (95% confidence interval (CI) 69.2 to 86.8) using re-operation for any cause as an endpoint and 85.3% (95% CI 75.9 to 91.8) using aseptic revision as an endpoint. This is significantly worse than that recorded in the published literature. These poor results have resulted in a significant impact on our service.

The clinical results of bilateral total knee replacement staged at a one-week interval during a single hospital admission were compared with bilateral total knee replacements performed under the same anaesthetic and with bilateral total knee replacements performed during two separate admissions. The data were retrospectively reviewed. All operations had been performed by the same surgeon using the same design of prosthesis at a single institution.

The operative time and length of stay for the one-week staged group were comparable with those of the separate admission group but longer than for the patients treated under one anaesthetic. There was a low rate of complications and good clinical outcome in all groups at a mean follow-up of four years (1 to 7.2). The group staged at a one-week interval had the least blood loss (p = 0.004).

With appropriate patient selection, bilateral total knee replacement performed under a single anaesthetic, or staged at a one-week interval, is a safe and effective method to treat bilateral arthritis of the knee.

The mortality following surgery in patients with a recent MI is high. Standard advice is to wait for a minimum of 6 months. In urgent situations, this may not be possible. From Jan 2003 to Aug 2004, 10 patients were admitted with fracture neck of femur and a recent MI proven by ECG changes or raised troponin. There were 7 females. The mean age was 79.5 yrs (59–95yrs). The premorbid mobility and co-morbidities were noted. Echocardiography was done in all patients preoperatively to assess the cardiac function. All patients were seen by physicians and anaesthetist pre-operatively. The mean time from infarction to operation was 11.5 days (3–23 days). The patients underwent either Thompsons hemiarthroplasty or DHS. The anaesthetic was performed by a consultant. Most patients received spinal anaesthesia (7/9). The anaesthetic records could not be found for 1 patient. 6 patients died within a month and 1 patient died within 6 month of operation. Despite thorough preoperative work-up and consultant anaesthesia, the mortality following surgery for proximal femur fractures in patients with recent myocardial infarction is 70% at 6 months. To our knowledge, there are no published mortality figures for this situation. This is much higher than the reported mortality following proximal femur fracture.

38 patients were taken from the arthroscopic washout waiting list and randomised after informed consent to receive either a course of sodium hyaluronate injections or an arthroscopic washout. Those patients who had previously had an arthroscopic washout, an intraarticular injection in the last 6 months, mechanical symptoms or hypersensitivity to avian proteins were excluded. The injections were given using an aseptic technique after first aspirating the knee to dryness. An injection was given each week for 5 weeks. The washouts were performed using 0. 9% saline and debridement was undertaken as necessary. The outcome measures used were a visual analogue pain score (VAS), Knee Society function score (FS) and Lequesne index (LI).

19 people were randomised into each group. The groups were similar in terms of age, sex and analgesics used. 2 patients in the arthroscopy group declined arthroscopy after randomisation as their symptoms had improved. There was no significant difference in the pre-intervention VAS or LI. The FS was worse in the arthroscopy group (p< 0. 01). After treatment, 2 patients in each group moved from the area and were lost to follow up.

During the year, 5 patients from the sodium hyaluronate group underwent arthroscopy. 3 patients failed to improve and were listed for total knee replacement. The others had improved at 3 months.

At 1 year, the VAS (NS), FS (p< 0. 02) and LI (p< 0. 04) were all better in the sodium hyaluronate group.

Intra-articular sodium hyaluronate injections should be considered for use in selected patients with knee osteoarthritis without mechanical problems. Further study is required to confirm these findings and improve patient selection.

Since described by Kashiwagi in 1978, the Outerbridge - Kashiwagi procedure (OK procedure) has been used to treat osteoarthritis of the elbow when simple measures have failed. Despite being used for 20 years, there have been surprisingly few series. The aim of this study was to assess the medium to long term results of the OK procedure and to analyse the preoperative and operative findings to identify features which predict a good outcome.

A consecutive series of 43 patients (44 elbows) underwent ulnohumeral debridement (OK procedure) for osteoarthritis of the elbow. Their mean age was 57 years (range 24 – 85 years) with one female patient. 35 patients (36 elbows) were reviewed after a mean follow up of 39 months (range 12 – 71 months). Overall, 81% of patients were satisfied with 12 good, 19 fair and 5 poor outcomes. The mean arc of flexion/extension (p=0.001), pain score (p=0.002) and locking (p=0.003) were significantly improved but a significant number of patients developed rest pain (p< 0.0001). There was a complication rate of 17% (2 ulna nerve entrapment, 1 ulna nerve neuropraxia which resolved completely, 1 superficial wound infection, 1 wound haematoma and 1 myocardial infarction). The reoperation rate was 8% (2 revision OK procedures and 1 ulna nerve decompression).

Patients with symptoms for less than 2 years, considerable preoperative pain or cubital tunnel syndrome had a significantly increased chance of a good outcome. The absence of preoperative locking was associated with a significantly increased chance of a poor outcome. Joint space narrowing on radiographs or presence of posterior loose bodies at operation was associated with an increased chance of a good outcome but these were not statistically significant. A history of trauma, the preoperative range of movement and Xray score did not predict outcome.