Tendons mainly consist of collagen in order to withstand high tensile forces. Compared to other, high turnover tissues, cellularity and vascularity in tendons are low. Thus, the natural healing process of tendons takes long and can be problematic. In case of injury to the enthesis, the special transition from tendon over cartilage to bone is replaced by a fibrous scar tissue, which remains an unsolved problem in rotator cuff repair.

To improve tendon healing, many different approaches have been described using scaffolds, stem cells, cytokines, blood products, gene therapy and others. Despite promising in vitro and in vivo results, translation to patient care is challenging. In clinics however, tendon auto- or allografts remain still first choice to augment tendon healing if needed.

Therefore, it is important to understand natural tendon properties and natural tendon healing first. Like in other tissues, senescence of tenocytes seems to play an important role for tendon degeneration which is interestingly not age depended. Our in vivo healing studies have shown improved and accelerated healing by adding collagen type I, which is now used in clinics, for example for augmentation of rotator cuff repair. Certain cytokines, cells and scaffolds may further improve tendon healing but are not yet used routinely, mainly due to missing clinical data, regulatory issues and costs.

In conclusion, the correct diagnosis and correct first line treatment of tendon injuries are important to avoid the necessity to biologically augment tendon healing. However, strategies to improve and accelerate tendon healing are still desirable. New treatment opportunities may arise with further advances in tendon engineering in the future.

Aims

Surgical site infection (SSI) is a common complication of surgery with an incidence of about 1% in the United Kingdom. Sutures can lead to the development of a SSI, as micro-organisms can colonize the suture as it is implanted. Triclosan-coated sutures, being antimicrobical, were developed to reduce the rate of SSI. Our aim was to assess whether triclosan-coated sutures cause a reduction in SSIs following arthroplasty of the hip and knee.

Background

Dislocation is a major complication following total hip arthroplasty (THA). Aetiology is multi-factorial, but increasing femoral head size may result in lower dislocation rates. The latest England and Wales National Joint Registry (NJR) annual report has highlighted a statistically significant increase in the use of femoral heads of size 36mm+ from 5% in 2005 to 26% in 2009, together with an increase in the use of the posterior approach. The aim of this study was to determine whether national dislocation rates have fallen over the same period.

Introduction

Rivaroxaban has been recommended for routine use as a thromboprophylactic agent in patients undergoing lower limb arthroplasty. Trials supporting its use have not fully evaluated the risks of wound complications related to rivaroxaban.

Background

The National Institute for Health and Clinical Effectiveness recommends both low molecular weight heparin (LMWH) and Rivaroxaban for venous thromboembolic (VTE) prophylaxis following lower limb arthroplasty. Despite evidence in the literature that suggests Rivaroxaban reduces VTE events, there are emerging concerns from the orthopaedic community regarding an increase in wound complications following its use.

Background

In 2011 20% of intracapsular fractured neck of femurs were treated with an uncemented hemiarthroplasty in the English NHS. National guidelines recommend cemented implants, based on evidence of less pain, better mobility and lower costs. We aimed to compare complications following cemented and uncemented hemiarthroplasty using the national hospital episode statistics (HES) database in England.

Introduction

The National Institute for Health and Clinical Effectiveness recommends both low molecular weight heparin (LMWH) and Rivaroxaban for venous thromboembolic (VTE) prophylaxis following lower limb arthroplasty. Despite evidence in the literature that suggests Rivaroxaban reduces VTE events, there are emerging concerns from the orthopaedic community regarding an increase in wound complications following its use.

Introduction

Tranexamic acid (TXA) reduces total knee replacement (TKR) & total hip replacement (THR) blood loss. We launched a ‘fast track’ protocol to reduce inpatient stay including a single 15mg/kg dose of TXA. We conducted a retrospective cohort analysis on haemoglobin balance and transfusion requirement before and after the protocol, which aimed to reduce blood loss during lower limb arthroplasty.

Antibiotic prophylaxis for joint replacement surgery is widely recommended and has been shown to reduce infection rates. Cephalosporins have commonly been used but are associated with development of Clostridium difficile associated diarrhoea (CDAD)

The purpose of this study was to assess whether a change of protocol aimed at reducing CDAD, including a change of antibiotic prophylaxis would reduce rates of CDAD and other postoperative complications.

We studied all 7989 patients in our trust that underwent hip or knee replacement from May 2002 to March 2009. These patients fell into two cohorts, firstly those who were prescribed cefuroxime as prophylaxis and secondly those prescribed gentamicin which was introduced following national concern regarding CDAD.

Following the change of prophylaxis from cefuroxime 750mg three doses to gentamicin 4.5 mg/kg single dose the rate of CDAD reduced significantly (0.17% to 0%, p<0.03), however the rate of acute renal failure (0.29% to 0.6%, p=0.04) and pneumonia (0.71% to 1.38%, p<0.01) increased significantly. The rate of urinary tract infection (1.44% to 1.20%, p >0.05) and the overall return to theatre rate (1.86% to 2.30%, p=0.21) were not significantly changed.

The spectrum of bacteria grown from infected joint replacements in the two cohorts was also analysed. The rate of deep MRSA infection was significantly less in the group given gentamicin. The frequency of other bacteria was also different between the cohorts, but not significantly so.

We conclude that changing protocol including antibiotic prophylaxis in joint replacement patients can have the desired effect on a particular outcome namely CDAD but can also result in increased rates of other postoperative complications. It is also likely to result in a change in the bacterial spectrum of infected joint replacements.

Purpose: To assess the infection rate following Lower Limb Arthroplasty using single dose gentamicin antibiotic prophylaxis compared to a traditional three doses of cephalosporin.

Method: All patients undergoing Total Hip and Knee replacements over six months (October 2007 to March 2008) at three participating hospitals were prospectively followed to assess perioperative infection rates using Surgical Site Surveillance(SSI) criteria. All patients received single dose antibiotic prophylaxis using intravenous Gentamicin 4.5mg/kg. This was compared with previous data collected over a 6 month period (Jan to Mar 2007 and Oct to Dec 2005) from the same hospitals using 3 doses of Cefuroxime 750mg. Return to theatre data was collected independently after introduction of gentamicin to compare with previous data. The change in creatinine level postoperatively was also measured in a selected group of patients.

Results: Four hundred and eight patients underwent Total Hip Replacements (THR) and 458 patients Total Knee Replacements (TKR) during the study period. This was compared with 414 and 421 patients who underwent THRs and TKRs respectively during a previous six month period. SSI was detected in 9 THRs(2.2%) and 2 TKRs(0.44%) in the study group as compared to 13 THRs(3.1%) and 12 TKRs(2.9%) in the control group. The infection rates in THRs were not significantly different between the 2 groups(p value−0.52) but were significantly reduced in the study group for TKRs(p value−0.005). The rate of Clostridium difficile infection was reduced within the hospital with the use of gentamicin, although other measures to reduce its incidence were also introduced. The return to theatre was 1.64%(23/1402) after introduction of Gentamicin as compared with 1.05%(21/2005) [p value−0.092] before this. This was a cause for concern although not significant. The day1 postoperative creatinine level increased by more than 30 units in 6% of patients on Gentamicin.

Conclusion: This study shows that the use of single dose prophylaxis using Gentamicin is effective for Lower Limb Arthroplasty. However, be wary of increased rate of return to theatre and the rise in creatinine level following use of gentamicin. Further period of evaluation and study is needed before it is recommended for routine use in present or modified form.

Introduction: Prophylactic systemic antibiotics are commonly used peri-operatively in primary hip and knee arthroplasty in the UK. ‘Fast-Track’ (FT) peri-operative care – a multimodal concept aiming to accelerate postoperative rehabilitation and reduce general morbidity – is also becoming more common in arthroplasty surgery. There are no published reports of acute kidney injury (AKI) as a result of a single-dose prophylactic Gentamicin. The renal impact of hypotensive anaesthesia and reduced routine post-operative intravenous fluid therapy, both features of FT protocol, has not yet been reported. Aim: To evaluate the renal impact of prophylactic Gentamicin and FT perioperative care in hip and knee arthroplasty surgery.

Methods: Four hundred and eighty-four total hip/knee arthroplasty patients had their pre-operative, first and third post-operative day serum creatinine concentration measured and recorded. The first 180 patients (group A) received 1.5g Cefuroxime at induction and two further doses of 750mg at 8 hours and 16 hours post-operatively as antibiotic prophylaxis. The next 160 patients (Group B) received 5mg/kg single-dose Gentamicin at induction instead of Cefuroxime. These patients (Group A and B) were not treated as per FT protocol. The final 144 patients (Group C) received the same Gentamicin as Group B and were treated as per FT protocol. Outcome measures were overall change and an increase of > 30 μmol/L, the latter signifying an AKI.

Results: Mean creatinine change at day 1 was −4.63 in Group A, −3.95 in Group B and 4.19 in Group C. Mean creatinine change by day 3 was −5.28 in Group A, −2.53 in Group B and 8.89 in Group C. No patients in Group A, 4 patients (2.56%) in Group B and 9 patients (6.66%) in Group C had a rise of > 30 μmol/L in day 1 creatinine concentrations.

Conclusions: Comparing the groups, there was no statistically significance change in the day 1 creatinine when Gentamicin replaced Cefuroxime (p=0.625,) however this became significant once FT was also introduced (p=0.001.) In terms of an important creatinine rise (AKI,) the change to Gentamicin produced a statistically significant rise in the number of patients with a day 1 creatinine rise > 30 μmol/L (p=0.048.) By day 3 there is no significant difference in the number of patients with a creatinine rise > 30 μmol/L.

Discussion: FT protocol aims to encourage haemostatic surgery and early ambulant patients (free from drip stands) at the expense of mild hypovolaemia. When these patients are also receiving Gentamicin, the kidneys are concentrating urine and Gentamicin in the tubules thus causing and AKI in some cases. It appears that Gentamicin and FT are cumulative in their effect on renal function.

Good medical practice predicates a contemporary knowledge of the literature to guide ones practice. The British edition of the Journal of Bone and Joint Surgery [JBJS (Br)] is considered one of the leading peer reviewed journals, guiding orthopaedic practice in the UK and abroad. Whilst seeking guidance on proposed changes to departmental policy, informal discussion with some high profile units raised concerns regarding the implementation of their published clinical recommendations. We intended to contact the publishing departments, to establish their routine practice with respect to the topic on which they have written in the literature.

We reviewed all articles published in JBJS (Br) over a 24 month period. Specifically we were seeking papers making recommendations for a change in practice. The originating department was contacted by telephone and communication sought from an individual not directly involved in the publication, but whom the change in practice stated in the literature would have direct impact.

Seventy-nine papers representing the work of 87 separate hospitals from 22 different countries were identified as making recommendations in any aspect of practice. We found that published articles were being followed in 56% of cases, 42% were not.

Our study demonstrates that a large proportion of institutions making clinical recommendations are not practicing them. Should the author’s own institution not follow their guidance, then how can the wider orthopaedic community be expected to follow? As such, have we exposed a fundamental flaw in the publication of clinical research?

In conclusion, we do practice what we preach… sometimes.

National Institute for Clinical Excellence (NICE) guidelines on venous thromboembolic (VTE) prophylaxis for patients undergoing orthopaedic surgery recommend that all inpatients be offered a low molecular weight heparin (LMWH).

Linked hospital episode statistics of 219602 patients were examined to determine the rates of complications following lower limb arthroplasty for the 12-month periods prior to and following the publication of these guidelines. This was compared with data from the National Joint Register (England and Wales) regarding LMWH usage during the same periods.

There was a significant increase in the reported use of LMWH (59.5 to 67.6%, p< 0.01) between the two periods. However, 90-day VTE events increased following both total hip (THR, 1.67% to 1.84%, p=0.06) and knee replacement (TKR, 1.99% to 2.04%, p=0.60). 30-day return to theatre rate for infection fell following TKR, but increased after THR. In addition, there were increases in rates of thrombocytopenia, which was significant following THR (p=0.03).

Recommendations from NICE are based on predicted reductions in VTE events, reducing morbidity, mortality and costs to the National Health Service. Early results in orthopaedic patients are unable to support these predictions.

Aim: To assess the infection rate following Lower Limb Arthroplasty using single dose gentamicin antibiotic prophylaxis compared to a traditional three doses of cephalosporin.

Material and Methods: All patients undergoing Total Hip and Knee joint replacements over 6 months (October 2007 to March 2008) at 3 participating hospitals were prospectively followed up to assess perioperative infection rates. Joint replacements were defined as having infection by the UK Health Protection Agency Surgical Site Surveillance criteria. All patients received single dose antibiotic prophylaxis using intravenous Gentamicin 4.5mg/kg body weight adjusted for body mass index.

This group of patients were compared with previous data collected over a 6 month period (Jan to Mar 2007 and Oct to Dec 2005) from the same hospitals for infection rates in Lower Limb Arthroplasty using 3 doses of Cefuroxime 750mg as antibiotic prophylaxis.

Results: 408 patients underwent Total Hip Replacements (THR) and 458 patients underwent Total Knee Replacements (TKR) during the study period. This was compared with 414 patients who underwent THR and 421 patients who underwent TKR during a 6 month period over 2 years.

Surgical site infection was detected in 9 THRs (2.2%) and 2 TKRs (0.44%) in the study group as compared to infection in 13 THRs (3.1%) and 12 TKRs (2.9%) in the control group.

Using the Fisher Exact test the infection rates in THRs were not significantly different between the 2 groups (p value – 0.52) but the infection rates were significantly reduced in the study group for TKRs (p value – 0.005).

There were no complications with the use of Gentamicin as antibiotic prophylaxis.

Cefuroxime is known to promote Clostridium difficile infection and was removed from the hospital pharmacy to help meet a UK government targets to reduce the incidence. The rate of Clostridium difficile infection was reduced within the hospital with the use of single dose antibiotic prophylaxis although other measures to reduce its incidence were also introduced.

Conclusions: This study shows that the use of single dose antibiotic prophylaxis using Gentamicin is effective for elective Lower Limb Arthroplasty.

This is recommended for routine use in all elective joint replacements as it is safe, effective and easy to administer.

Purpose: Recent animal evidence has suggested that Bupivicaine may be harmful to articular cartilage. The purpose of this study was establish whether, following arthroscopy of the knee, infiltration of Bupivicaine around the portals is as effective as intra-articular infiltration for post-operative analgesia.

Method: Consecutive patients attending for knee arthroscopy were consented and randomised to one of two groups. Following arthroscopy, Group I received 20mls 0.5% Bupivicaine infiltrated into the joint; Group II received 20mls 0.5% Bupivicaine infiltrated around the portals. A Visual Analogue Score (VAS) was collected at one hour post-operatively and rescue analgesia recorded. A power calculation was performed. Ethical approval was granted.

Results: There were 68 patients in Group I (intra-articular) and 69 patients in Group II (portal). There was no significant difference in the age or sex distribution of patients in either group. The mean VAS score was 3.04 in Group I and 3.24 in Group II. There was no significant difference between the two groups (p=0.619). There was also no significant difference in the need for rescue analgesia (p=0.930). The study has demonstrated equivalence between the two groups, within one VAS point (Power = 80%).

Conclusion: We would recommend that following knee arthroscopy, Bupivicaine should be infiltrated around the portals, avoiding intra-articular infiltration.

The administration of intra-articular local anaesthetic is common following arthroscopy of the knee. However, recent evidence has suggested that bupivacaine may be harmful to articular cartilage. This study aimed to establish whether infiltration of bupivacaine around the portals is as effective as intra-articular injection.

We randomised 137 patients to receive either 20 ml 0.5% bupivacaine introduced into the joint (group 1) or 20 ml 0.5% bupivacaine infiltrated only around the portals (group 2) following arthroscopy. A visual analogue scale was administered one hour post-operatively to assess pain relief. Both patients and observers were blinded to the treatment group. A power calculation was performed.

The mean visual analogue score was 3.24 (sd 2.20) in group I and 3.04 (sd 2.31) in group 2. This difference was not statistically significant (p = 0.62).

Infiltration of bupivacaine around the portals had an equivalent effect on pain scores at one hour, and we would therefore recommend this technique to avoid the possible chondrotoxic effect of intra-articular bupivacaine.

Digital radiography is becoming widespread. Accurate pre-operative templating of digital images of the hip traditionally involves positioning a calibration object at its centre. This can be difficult and cause embarrassment. We have devised a method whereby a planar disc placed on the radiographic cassette accounts for the expected magnification. Initial examination of 50 pelvic CT scans showed a mean hip centre distance of 117 mm (79 to 142) above the gluteal skin. Further calculations predicted that a disc of 37.17 mm diameter, placed on the cassette, would appear identical to a 30 mm sphere placed at the level of the centre of the hip as requested by our templating software. We assessed accuracy and reproducibility by ‘reverse calibration’ of 20 radiographs taken three months after hip replacement using simultaneous sphere and disc methods, and a further 20 with a precision disc of accurate size. Even when variations in patient size were ignored, the disc proved more accurate and reliable than the sphere.

The technique is reliable, robust, cost effective and acceptable to patients and radiographers. It can easily be used in any radiography department after a few simple calculations and manufacture of appropriately-sized discs.

We report the results of a prospective randomised controlled clinical trial assessing the radiosterophotogrametric analysis (RSA), clinical and radiological performance of a metal backed and an all-polyethylene tibial cruciate retaining, condylar design, PFC-TKA up to twenty four months.

65 patients were recruited, of which 41 patients were randomised. There were 20 metal backed and 21 all-polyethylene. None were lost to follow-up. There were no significant inter-group demographic differences. We found a significant increase in SF-12 and Oxford knee scores after surgery in both groups. No significant difference was found between the groups in the RSA, SF-12, Oxford Knee score, radiological alignment and range of movement at 6, 12 or 24 months. At 2 years one metal backed implant showed translational migration > 1mm. No all polyethylene implant migrated > 1mm. Further analysis identified possible progressive subsidence of the metal backed implants compared to all-polyethylene implants, although the magnitude of this difference was very small.

We conclude that in the uncomplicated primary total knee arthroplasty, all polyethylene PFC-_ tibial prostheses had equivalent performance to the metal backed counterpart, using RSA as the primary assessment instrument at 24 months. We found no differences between the two designs as assessed by the secondary instruments: SF-12, Oxford knee score, alignment and range of movement at 24 months. Should half of all primary total knee replacements performed in the UK receive an all-polyethylene tibial implant, the estimated annual cost saving would be 21 million pounds per annum.

Introduction: Aseptic loosening is the commonest complication of cemented total hip arthroplasy. Gaseous voids within the cement mantle are thought to act as stress concentrators and points of origin and preferential fracture propagation at the cement stem interface. Assuming a bone tempereature of 37°C, Bishop recommended heating the prosthesis to 44°C, thereby effecting a reduction in cement-prosthesis interface porosity.

The aim of this study was to (I) determine the intra-operative temperature of the femoral cancellous bed prior to insertion of prosthesis, (II) to investigate whether the magnitude of the temperature gradient effects interface porosity (III) to develop clinically relevant recommendations.

Materials and Methods: (I) The intra-operative determination of femoral cancellous boney bed temperature. Sterile, single use thermocouples (Mon-a-therm) were used to record interface temperature in six patients, after canal preparation and lavage. (II) A simulated femoral model was designed consisting of a waterbath, set at temperature determined by (I) with an inner water-tight chamber formed by 19mm diameter polyethylene tubing. Cement (Palacos) was non-vacuum mixed (to exaggerate porosity) for 1 minute and injected in a retrograde manner into the inner tube at 3 minutes. Femoral stems (Exeter) were pre-heated in a second waterbath to 18, 32,35,37,40,44°C, were thoroughly dried and lowered into the inner tube by a Lloyd universal testing machine via a custom jig. The cement was left to polymerise.

The cement mantle was sectioned transversely, then longitudinally to expose the cement-prosthesis interface. This was stained with acrylic dye to facilitate image analysis. Three mantles for each temperature were produced.

Results: (I) The mean femoral canal temperature was 32.3°C, (II) the effect of stem temperature on interface porosity is shown in fig1.

Conclusions: Bone temperature is 32°C after canal preparation using contemporary cementing techniques. Heating to 35°C reduces interface porosity, heating to 40°C is optimal.