The aim of this study was to measure the effect of hospital case volume on the survival of revision total hip arthroplasty (RTHA). This is a retrospective analysis of Scottish Arthroplasty Project data, a nationwide audit which prospectively collects data on all arthroplasty procedures performed in Scotland. The primary outcome was RTHA survival at ten years. The primary explanatory variable was the effect of hospital case volume per year on RTHA survival. Kaplan-Meier survival curves were plotted with 95% confidence intervals (CIs) to determine the lifespan of RTHA. Multivariate Cox proportional hazards were used to estimate relative revision risks over time. Hazard ratios (HRs) were reported with 95% CI, and p-value < 0.05 was considered statistically significant. From 1999 to 2019, 13,020 patients underwent RTHA surgery in Scotland (median age at RTHA 70 years (interquartile range (IQR) 62 to 77)). In all, 5,721 (43.9%) were female, and 1065 (8.2%) were treated for infection. 714 (5.5%) underwent a second revision procedure. Co-morbidity, younger age at index revision, and positive infection status were associated with need for re-revision (p<0.001). The ten-year survival estimate for RTHA was 93.3% (95% CI 92.8 to 93.8). Adjusting for sex, age, surgeon volume, and indication for revision, high hospital case volume was not significantly associated with lower risk of re-revision (HR1, 95% CI 1.00 to 1.00, p 0.073)). The majority of RTHA in Scotland survive up to ten years. Increasing yearly hospital case volume cases is not independently associated with a significant risk reduction of re-revision

The aims of this study in relation to distal radius fractures were to determine (1) the floor and ceiling effects for the QuickDASH and PRWE, (2) the floor and ceiling effects when defined to be within the minimal clinically important difference (MCID) of the minimal or maximal scores, (3) the degree to which patients with a floor or ceiling effect felt that their wrist was ‘normal’, and (4) patent factors associated with a floor or ceiling effect. A retrospective cohort study of patients sustaining a distal radius fracture during a single year was undertaken. Outcome measures included the QuickDASH, PRWE, EQ-5D-3L and normal wrist score. There were 526 patients with a mean age of 65yrs and 77% were female. Most patients were managed non-operatively (73%, n=385). The mean follow-up was 4.8yrs. A ceiling effect was observed for both the QuickDASH (22.3%) and PRWE (28.5%). When defined to be within the MCID of the best score, the effect increased to 62.8% for the QuickDASH and 60% for PRWE. Patients that achieved the best functional outcome according to the QuickDASH and PRWE felt their wrist was only 91% and 92% normal, respectively. Sex (p=0.000), age (p=0.000), dominant wrist injury (p=0.006 for QuickDASH and p=0.038 for PRWE), fracture type (p=0.015), and a better health-related quality of life (p=0.000) were independently associated with achieving a ceiling score. The QuickDASH and PRWE demonstrated ceiling effects following a distal radius fracture. Patients achieving ceiling scores did not consider their wrist to be ‘normal’ for them

Revision Total Knee Arthroplasty (rTKA) is predicted to increase by more than 600% between 2005 and 2030. The survivorship of primary TKA has been extensively investigated, however more granular information on the risks of rTKA is needed. The aim of the study was to investigate the incidence of re-revision TKA, with explanatory variables of time from primary to revision, and indication (aseptic vs septic). Secondary aim was to investigate mortality. This is an analysis of the Scottish Arthroplasty Project data set, a national audit prospectively recording data on all joint replacements performed in Scotland. The period from 2000 to 2019 was studied. 4723 patients underwent revision TKA. The relationship between time from primary to revision TKA and 2nd revision was significant (p<0.001), with increasing time lowering probability of re-revision (OR 0.99 95% CI 0.987 to 0.993). There was no significant association in time to first revision on time from 1st revision to re-revision (p>0.05). Overall mortality for all patients was 32% at 10 years (95% CI 31-34), Time from primary TKA to revision TKA had a significant effect on mortality: p=0.004 OR 1.03 (1.01-1.05). Septic revisions had a reduced mortality compared to aseptic, OR 0.95 (0.71-1.25) however this was not significant (p=0.69). This is the first study to demonstrate time from primary TKA to revision TKA having a significant effect on probability of re-revision TKA. Furthermore the study suggests mortality is increased with increasing time from primary procedure to revision, however decreased if the indication is septic rather than aseptic

Aims. Little is known about the effect of haemorrhagic shock and resuscitation on fracture healing. This study used a rabbit model with a femoral osteotomy and fixation to examine this relationship. Materials and Methods. A total of 18 male New Zealand white rabbits underwent femoral osteotomy with intramedullary fixation with ‘shock’ (n = 9) and control (n = 9) groups. Shock was induced in the study group by removal of 35% of the total blood volume 45 minutes before resuscitation with blood and crystalloid. Fracture healing was monitored for eight weeks using serum markers of healing and radiographs. Results. Four animals were excluded due to postoperative complications. The serum concentration of osteocalcin was significantly elevated in the shock group postoperatively (p < 0.0001). There were otherwise no differences with regard to serum markers of bone healing. The callus index was consistently increased in the shock group on anteroposterior (p = 0.0069) and lateral (p = 0.0165) radiographs from three weeks postoperatively. The control group showed an earlier decrease of callus index. Radiographic scores were significantly greater in the control group (p = 0.0025). Conclusion. In a rabbit femoral osteotomy model with intramedullary fixation, haemorrhagic shock and resuscitation produced larger callus but with evidence of delayed remodelling. Cite this article: Bone Joint J 2018;100-B:1234–40

Hip fractures are a major cause of morbidity and mortality, and malnutrition is a critical determinant of these outcomes. This systematic review and meta-analysis aims to determine whether oral nutritional supplementation (ONS) improves postoperative outcomes in older patients with hip fracture. An electronic systematic literature search was conducted in August 2022 using four databases. Randomized trials documenting ONS in older patients with hip fracture (aged 50+) were included. Two reviewers evaluated study eligibility, data extraction and assessed study quality.

There were 812 studies identified of which 18 studies involving 1,512 patients met the inclusion criteria. The overall meta-analysis demonstrates that ONS was associated with a significant risk reduction in infective complications (odds ratio (OR) 0.54, 95%CI 0.38, 0.76), pressure ulcers (OR 0.54, 95%CI 0.33, 0.88), total complications rate (OR 0.57, 95%CI 0.42, 0.79). Length of hospital stay (LOS) was also significantly reduced (weighted mean difference (WMD) −2.01, 95%CI −3.52, −0.5), particularly in the rehabilitation LOS (WMD −4.17, 95%CI −7.08, −1.26). There was a tendency towards lower risk in mortality (OR 0.93, 95%CI 0.62, 1.4) and readmission (OR 0.52, 95%CI 0.16, 1.73), though statistical significance was not achieved. The overall compliance to ONS ranged from 64.1% to 100%, but no factors influencing compliance were identified.

This systematic review was the first to quantitatively demonstrate that ONS reduces half the risk of infective complications, pressure ulcers, total complication rate and reduces LOS. ONS should be a regular and integrated part of medical practice, especially given that the compliance to ONS is acceptable.

Aims

Despite long-standing dogma, a clear relationship between the timing of surgical irrigation and debridement (I&D) and the development of subsequent deep infection has not been established in the literature. Traditionally, I&D of an open fracture has been recommended within six hours of injury based on animal studies from the 1970s, however the clinical basis for this remains unclear. Using data from a multicentre randomized controlled trial of 2,447 open fracture patients, the primary objective of this secondary analysis is to determine if a relationship exists between timing of wound I&D (within six hours of injury vs beyond six hours) and subsequent reoperation rate for infection or healing complications within one year for patients with open limb fractures requiring surgical treatment.

Introduction. Closed avulsion of the Flexor Digitorum Profundus (FDP) from distal phalanx most commonly affects the ring finger when an extensive force is applied to a finger in active flexion. Whilst it is undoubtably reasonable to provide treatment for those who present with symptoms, there may be a cohort of people who sustain an avulsion without noticing. This study aims to quantify the effect of ring finger FDP avulsion on overall grip strength to determine the functional effect of a missed injury. Method. Right handed volunteers, with no abnormality on examination were included (N= 42). Proximal muscle group action was excluded. Grip strength was tested using a Jamar dynamometer with and without splinting of the ring finger to block flexion at the DIPJ and repeated six times alternately to mitigate the effects of fatigue. Results. Most subjects showed a small (0.3–3kg) change in their average grip strength with the splint (N= 29). Some showed a dramatic change in their grip strength (6–11.4) (N=6) others showed no change or slight improvement with the splint (−3–0) (N=7). Data were not normally distributed (kolmogorov-smirnov p=0.023). A wilcoxon signed rank test showed a statistically significant difference in performance with, compared to without, the splint, mean 2.34kg reduction (−3.3 − 11.4) (p <0.0005. Discussion. Horton et al have examined the quadriga effect and shown that the individual strength of other digits is reduced when one FDP is isolated. This implies overall grip strength should be reduced; our data supports this assertion. However despite splinting, the majority of subjects were still within the normal range of power for age. Larger scale studies are required to assess the functional effect of repair vs conservative management

Introduction. The degeneration of the adjacent segment in lumbar spine with spondylodesis is well known, though the exact incidence and the mechanism is not clear. Several implants with semi rigid or dynamic behavior are available to reduce the biomechanical loads and to prevent an adjacent segment disease (ASD). Randomized controlled trials are not published. We investigated the biomechanical influence of dynamic and semi rigid implants on the adjacent segment in cadaver lumbar spine with monosegmental fusion (MF). Materials and Methods. 14 fresh cadaver lumbar spines were prepared; capsules and ligaments were kept intact. Pure rotanional moments of ±7.5 Nm were applied with a Zwick 1456 universal testing machine without preload in lateral bending and flexion/extension. The intradiscal pressure (IDP) and the range of motion (ROM) were measured in the segments L2/3 and L3/4 in following situations: in the native spine, monosegmental fusion L4/5 (MF), MF with dynamic rod to L3/4 (Dynabolt), MF with interspinous implant L3/4 (Coflex), and semi rigid fusion with PEEK rod (CD Horizon Legacy) L3-L5. Results. Under flexion load all implants reduced the IDP of segment L2/L3, whereas the IDP in the segment L3/4 was increased using interspinous implants in comparison to the other groups. The IDP was reduced in extension in both segments for all semi rigid or dynamic implants. Compared under extension to the native spine the MF had no influence on the IDP of the adjacent disc. The rod instrumentation (Dynabolt, PEEK rod) lead to a decreased IDP in lateral bending tests. The ROM in L3 was reduced in all groups compared to the native spine. The dynamic and semi rigid stabilization in the segment L3/4 limited the ROM more than the MF. Discussion. The MF reduced the ROM in all directions, whereas the IDP of the adjacent segment remained unaffected. The support of the adjacent segment by semi rigid and dynamic implants decreased the IDP of both segments in extension mainly. This fact is an agreement with other studies. Compared to our data, no significant effect on the adjacent levels was observed. Interestingly, in our study, the IDP of the adjacent segment is unaffected by MF. The biomechanical influence in the view of an ASD could be comprehended, but is not completely clear. The fact of persistent IDP in the adjacent segment suggests that MF has a lower effect on the adjacent segment degeneration as presumed. Biomechanical studies with human cadaver lumbar spines are limited and depend on age and degenerative situation. The effect on supporting implants on adjacent segment disease in lumbar spine surgery has to be investigated in clinical long term studies

Aims. To evaluate the effect of a single early high-dose vitamin D supplement on fracture union in patients with hypovitaminosis D and a long bone fracture. Patients and Methods. Between July 2011 and August 2013, 113 adults with a long bone fracture were enrolled in a prospective randomised double-blind placebo-controlled trial. Their serum vitamin D levels were measured and a total of 100 patients were found to be vitamin D deficient (< 20 ng/ml) or insufficient (< 30 ng/mL). These were then randomised to receive a single dose of vitamin D. 3. orally (100 000 IU) within two weeks of injury (treatment group, n = 50) or a placebo (control group, n = 50). We recorded patient demographics, fracture location and treatment, vitamin D level, time to fracture union and complications, including vitamin D toxicity. Outcomes included union, nonunion or complication requiring an early, unplanned secondary procedure. Patients without an outcome at 15 months and no scheduled follow-up were considered lost to follow-up. The t-test and cross tabulations verified the adequacy of randomisation. An intention-to-treat analysis was carried out. Results. In all, 100 (89%) patients had hypovitaminosis D. Both treatment and control groups had similar demographics and injury characteristics. The initial median vitamin D levels were 16 ng/mL (interquartile range 5 to 28) in both groups (p = 0.885). A total of 14 patients were lost to follow-up (seven from each group), two had fixation failure (one in each group) and one control group patient developed an infection. Overall, the nonunion rate was 4% (two per group). No patient showed signs of clinical toxicity from their supplement. Conclusions. Despite finding a high level of hypovitaminosis D, the rate of union was high and independent of supplementation with vitamin D. 3. . Cite this article: Bone Joint J 2017;99-B:1520–5

Extracorporeal irradiation and re-implantation of a bone segment is a technique employed in bone sarcoma surgery for limb salvage in the setting of reasonable bone stock. There is neither consensus nor rationale given for the dosage of irradiation used in previous studies, with values of up to 300Gy applied. We investigated the influence of extracorporeal irradiation on the elastic and viscoelastic properties of bone. Bone specimens were extracted from mature cattle and subdivided into thirteen groups; twelve groups exposed to increasing levels of irradiation and a control group. The specimens, once irradiated, underwent mechanical testing in saline at 37°C. Mechanical properties were calculated by experimental means which included Young's Modulus, Poisson's Ratio, Dissipation Factor, Storage Modulus, Loss Modulus and Dynamic Modulus. These were all obtained for comparison of the irradiated specimens to the control group. We found there to be a statistically significant increase in Poisson's ratio after increasing irradiation doses up to 300Gy were applied. However, there was negligible change in all other mechanical properties of bone that were assessed. Therefore, we conclude that the overall mechanical effect of high levels of extracorporeal irradiation (300Gy) is minute, and can be administered to reduce the risk of malignancy recurrence

In some centres, serial bedside aspirations, in association with intravenous antibiotics, are still an accepted treatment for septic arthritis (Mathews, Postgraduate Medical Journal, 2008). However, there is a risk that bacterial products remain in the joint, even when the bacteria have been destroyed. We have conducted a study to ascertain whether bacterial products alone have an effect on in situ chondrocyte viability. A hip aspirate (25μl), containing Staphylococcus aureus, from a patient with septic arthritis was added to 5ml culture medium and incubated (37°C) for 48hrs. The solution was then centrifuged (3400g for 10mins) and the supernatant removed. Cartilage explants were harvested from a bovine metacarpophalangeal joint, placed into the bacterial supernatant and incubated at 37°C. Explants were removed at hourly intervals over a 6-hour period and stained with the fluorescent probes chloromethylfluorescein di-acetate (10μM) and propidium iodide (10μM) to label living chondrocytes green and dead cells red respectively. Following imaging of cartilage by confocal microscopy, the percentage cell death at each time point was obtained using Volocity 4 software. Chondrocyte death increased markedly with time: 0.04% at 2hrs, 28% at 4hrs and 39% at 6hrs. This study shows that bacterial products rapidly penetrate the cartilage matrix and have a damaging effect on in situ chondrocyte viability. Further work will clarify the contributions made by the various toxic components in the culture supernatant, but these data support the need to remove the bacteria and their products aggressively as part of the treatment of septic arthritis

We have studied the effect of shortening of the femoral neck and varus collapse on the functional capacity and quality of life of patients who had undergone fixation of an isolated intracapsular fracture of the hip with cancellous screws. After screening 660 patients at four university medical centres, 70 patients with a mean age of 71 years (20 to 90) met the inclusion criteria. Overall, 66% (46 of 70) of the fractures healed with > 5 mm of shortening and 39% (27 of 70) with > 5° of varus. Patients with severe shortening of the femoral neck had significantly lower short form-36 questionnaire (SF-36) physical functioning scores (no/mild (< 5 mm) vs severe shortening (> 10 mm); 74 vs 42 points, p < 0.001). A similar effect was noted with moderate shortening, suggesting a gradient effect (no/mild (< 5 mm) vs moderate shortening (5 to 10 mm); 74 vs 53 points, p = 0.011). Varus collapse correlated moderately with the occurrence of shortening (r = 0.66, p < 0.001). Shortening also resulted in a significantly lower EuroQol questionnaire (EQ5D) index scores (p = 0.05). In a regression analysis shortening of the femoral neck was the only significant variable predictive of a low SF-36 physical functioning score (p < 0.001)

25–40% of unicompartmental knee replacement (UKR) revisions are performed for unexplained pain possibly secondary to elevated proximal tibial bone strain. This study investigates the effect of tibial component metal backing and polyethylene thickness on cancellous bone strain in a finite element model (FEM) of a cemented fixed bearing medial UKR, validated using previously published acoustic emission data (AE). FEMs of composite tibiae implanted with an all-polyethylene tibial component (AP) and a metal backed one (MB) were created. Polyethylene of thickness 6–10mm in 2mm increments was loaded to a medial load of 2500N. The volume of cancellous bone exposed to <−3000 (pathological overloading) and <−7000 (failure limit) minimum principal (compressive) microstrain (µ∊) and >3000 and >7000 maximum principal (tensile) microstrain was measured. Linear regression analysis showed good correlation between measured AE hits and volume of cancellous bone elements with compressive strain <−3000µ∊: correlation coefficients (R= 0.947, R2 = 0.847), standard error of the estimate (12.6 AE hits) and percentage error (12.5%) (p<0.001). AP implants displayed greater cancellous bone strains than MB implants for all strain variables at all loads. Patterns of strain differed between implants: MB concentrations at the lateral edge; AP concentrations at the keel, peg and at the region of load application. AP implants had 2.2 (10mm) to 3.2 (6mm) times the volume of cancellous bone compressively strained <−7000µ∊ than the MB implants. Altering MB polyethylene insert thickness had no effect. We advocate using caution with all-polyethylene UKR implants especially in large or active patients where loads are higher

Introduction. It was the purpose to evaluate the biomechanical changes that occur after optimal and non-optimal component placement of a hip resurfacing (SRA) by using a subject specific musculoskeletal model based on CT-scan data. Materials and Methods. Nineteen hips from 11 cadavers were resurfaced with a BHR using a femoral navigation system. CT images were acquired before and after surgery. Grey-value segmentation in Mimics produced contours representing the bone geometry and identifying the outlines of the 3 parts of the gluteus medius. The anatomical changes induced by the procedure were characterised by the translation of the hip joint center (HJCR) with respect to the pelvic and femoral bone. The contact forces during normal gait with ‘optimal’ component placement were calculated for a cement mantle of 3 mm, a socket inclination of 45° and anteversion of 15°. The biomechanical effect of ‘non-optimal placement’ was simulated by varying the positioning of the components. Results. There was a significant (p<0.01) shortening of the muscle length with the ‘optimal’ component placement for all parts of the gluteus medius with the largest shortening of the posterior part by 6mm. This was caused by a significant shortening of the femoral offset by 2.3mm (p<0.01). Because of a significant (p<0.01) medialisation of the HJCR by 4 mm, there was no significant increase in contact force. The hip joint contact forces increased by 0.5% per mm HJCR displacement. Each millimeter of cranial and lateral displacement of the femoral HJCR increased the contact force by 0.5% and 1%, respectively. The contact stresses changed significantly by 0.8% and 0.2% per degree of socket inclination and anteversion. The contact force increased 1% per mm lateral displacement of the acetabular HJCR. Discussion. Optimal placement of the SRA components did not completely restore the biomechanics of the native hip joint. The contact forces were not increased due to the compensatory effect of the medialisation of the acetabular HJCR. This suggests that reaming to the acetabular floor should be conducted in SRA. Femoral component displacement in the cranial and lateral direction significantly increased the hip joint loading. Errors of socket placement in the coronal and sagital plane significantly increased the contact stresses. Accumulative errors of both component displacements could lead to increased contact stresses of 18% to 23% with socket inclinations of 50° and 55°. Surgeons should reconsider continuing the SRA procedure if a neck length loss and lateralisation of the HCJR by >5 mm is anticipated as this would increase the contact stresses by >12%

We evaluated the effect of low-intensity pulsed ultrasound stimulation (LIPUS) on the remodelling of callus in a rabbit gap-healing model by bone morphometric analyses using three-dimensional quantitative micro-CT. A tibial osteotomy with a 2 mm gap was immobilised by rigid external fixation and LIPUS was applied using active translucent devices. A control group had sham inactive transducers applied. A region of interest of micro-CT was set at the centre of the osteotomy gap with a width of 1 mm. The morphometric parameters used for evaluation were the volume of mineralised callus (BV) and the volumetric bone mineral density of mineralised tissue (mBMD). The whole region of interest was measured and subdivided into three zones as follows: the periosteal callus zone (external), the medullary callus zone (endosteal) and the cortical gap zone (intercortical). The BV and mBMD were measured for each zone. In the endosteal area, there was a significant increase in the density of newly formed callus which was subsequently diminished by bone resorption that overwhelmed bone formation in this area as the intramedullary canal was restored. In the intercortical area, LIPUS was considered to enhance bone formation throughout the period of observation. These findings indicate that LIPUS could shorten the time required for remodelling and enhance the mineralisation of callus

Staphylococcus aureus is responsible for 60–70% infections of surgical implants and prostheses in Orthopaedic surgery, costing the NHS £120–200 million per annum. Its ability to develop resistance or tolerance to a diverse range of antimicrobial compounds, threatens to halt routine elective implant surgery. One strategy to overcome this problem is to look beyond traditional antimicrobial drug therapies and investigate other treatment modalities. Biophysical modalities, such as ultrasound, are poorly explored, but preliminary work has shown potential benefit, especially when combined with existing antibiotics.

Using a methicillin-sensitive S. aureus reference strain and the dissolvable bead assay, biofilms were challenged by a low-intensity ultrasound (1.5MHz, 30mW/cm2, pulse duration 200µs/1KHz) for 20 minutes and gentamicin. The outcome measures were colony-forming units/mL (CFU/mL) and the minimum biofilm eradication concentration (MBEC) of gentamicin. The mean number of S. aureus within control biofilms was 1.04 × 109 CFU/mL. There was no clinically or statistically significant (p=0.531) reduction in viable S. aureus following ultrasound therapy alone. The MBEC of gentamicin for this S. aureus strain was 256 mg/L. The MBEC of gentamicin with the addition of ultrasound was 64mg/L. Further studies confirmed that the mechanism of action was due to incomplete disruption of the extracellular matrix with subsequent metabolic stimulation of the dormant biofilm-associated bacteria due to increased nutrient availability and oxygen tension.

Low intensity pulsed ultrasound was associated with a 4-fold reduction in the effective biofilm eradication concentration of gentamicin; bringing the MBEC of gentamicin to within clinically achievable concentrations.

INTRODUCTION. The introduction of hard-on-hard bearings and the consequences of increased wear due to edge-loading have renewed interest in the importance of acetabular component orientation for implant survival and functional outcome following hip arthroplasty. Some studies have shown increased dislocation risk when the cup is mal-oriented which has led to the identification of a safe-zone1. The aims of this prospective, multi-centered study of primary total hip arthroplasty (THA) were to: 1. Identify factors that influence cup orientation and 2. Describe the effect of cup orientation on clinical outcome. METHODS. In a prospective study involving seven UK centers, patients undergoing primary THA between January 1999 and January 2002 were recruited. All patients underwent detailed assessment pre-operatively as well as post-op. Assessment included data on patient demographics, clinical outcome, complications and further surgery/revision. 681 primary THAs had adequate radiographs for inclusion. 590 hips received cemented cups. The primary functional outcome measure of the study was the change between pre-operative and at latest follow up OHS (OHS). Secondary outcome measures included dislocation rate and revision surgery. EBRA was used to determine acetabular inclination and version. The influence of patient's gender, BMI, surgeon's grade and approach on cup orientation was examined. Four different zones tested as possibly ± (Lewinnek Zone, Callanan's described zone and zones ± 5 and ±10 about the study's mean inclination and anteversion) for a reduced dislocation risk and an optimal functional outcome. RESULTS. There were 21 dislocations (3.1%) and 8 (1.2%) patients required revision at a mean follow up of 7 years. Experienced surgeons (2=0.047) and those operating with the patient in the lateral decubitus position (p=0.04) were more likely to achieve a cup orientation within any of the tested zones. Surgical approach (2=0.14) and patient's BMI (2=0.93) had no influence on whether a cup was within or outside any zone. There was no difference in dislocation rate between the posterior and anterio-lateral approaches (2=0.88). None of the zones tested had a significantly reduced dislocation risk (2=0.13), nor revision risk (2=0.55). OHS was not different for patients with cups within or outside any of the zones tested (p=0.523). DISCUSSION. There was a wide variation in cup orientation. Despite the wide scatter in cup orientation, no safe zone could be identified that would reduce dislocation and revision rate, nor improve patient reported outcome (OHS). Hence, these data suggest that acetabular component orientation should not be considered predictive of patients' early/mid-term complication/revision rate and outcome following THA

We aimed to investigate the effect of Seprafilm®, a synthetic biomembran, on the intra-articular adhesion formation in an experimental arthrofibrosis model. Twenty male white rabbits were randomly allocated into two groups of 10 animals in each. A standard surgical procedure aiming at the development of arthrofibrosis and including medial parapatellar arthrotomy, lateral eversion of the patella, partial synovectomy and debridement of anterior of supracondylar area and patella joint surface by scalpel was performed on all rabbits' right knees. Group 1 rabbits served as controls, and in Group 2 rabbits a Seprafilm®, barrier placed into the described area. In both groups, after surgery, knee joint was immobilized by a no.5 wire suture passing from the ankle and groin and keeping the joint in 140° of flexion. At 6th week, all animals were sacrificed and adhesion formation was evaluated both macroscopically and histo-pathologically. All data were semi-quantified and analyzed statistically by Fisher's exact test. While all rabbits in control group displayed different rates of adhesion macroscopically (62.5% severe, 25% moderate, 12.5% mild), none in the study group had it. The average macroscopic adhesion score was 2.5 ± 0.75 in control group, and 0 in Seprafilm® group. Histopathologic evaluation also revealed microscopic adhesion in all rabbits in control group, but none in Seprafilm® group. Fibroblast proliferation in Seprafilm® group (100% mild) was significantly lower than in control group (62.5% severe, 37.5% moderate) (p<0.05). In conclusion, use of Seprafilm® as a mechanical barrier may be of value against the formation of arthrofibrosis in risky knees such as septic and traumatic ones

Background. It is unclear which form of anaesthesia is the most favourable in primary total hip replacement (THR) surgery. A recently published systematic review of modern anaesthesia techniques in primary THR surgery (Macfarlane 2009) was not able to show any convincing benefit of regional or general anaesthesia. One retrospective study that examined anaesthesia and leg length (Sathappan 2008), found an increased incidence of leg length difference > 5 mm in those patients who were operated with regional anaesthesia. Our department used a mini invasive approach in supine as standard procedure in THR. The type of anaesthesia that is chosen is up to the individual anaesthetist. Purpose. We wanted to see if there was any correlation between type of anaesthesia and leg length, total time spent in theatre and recovery room, postoperative hospital stay, blood loss or operating time in primary THR surgery with a mini invasive approach in supine. Materials and Methods. Our study was a retrospective study of 170 primary THR patients. All patients received an uncemented Corail stem and a cemented Marathon cup. Patients with abnormal anatomy, BMI > 46, simultaneous removal of internal fixation or incomplete data were excluded in the analysis. Radiograpic leg length was measured using the inter teardrop line and the lesser trochanter. Results. 99 patients were operated on with spinal anaesthesia and 71 with total intravenous anaesthesia (TIVA). There were 65% women in both groups. Average age was 74 years (32–95) in the spinal anaesthesia group and 67 years (38–93) in the TIVA group. We found no significant difference in the average operating time (spinal 65 min, TIVA 64 min), drop in haemoglobin to the first postoperative day (spinal 16%, TIVA 16%), postoperative hospital stay (Spinal 1.4 days, TIVA 1.4) or in transfusion rate (spinal 1%, TIVA 1.4%). We found a significant difference in the proportion of patients with a leg length difference of more than 7 mm (Spinal 22%, TIVA 6%, p = 0.02) and the average total time spent in theatre and post-operative department (spinal 325 min, TIVA 293 min, p < 001). Discussion. The study is retrospective and is therefore fettered by the limitations inherent in such a study. Our study seems to confirm the earlier findings that the type of anaesthesia can affect leg length in primary THR. It is speculated that spinal anaesthesia has a more unpredictable effect on muscular tension which could explain this

We retrospectively reviewed 2989 consecutive patients with a mean age of 81 (21 to 105) and a female to male ratio of 5:2 who were admitted to our hip fracture unit between July 2009 and February 2013. We compared weekday and weekend admission and weekday and weekend surgery 30-day mortality rates for hip fractures treated both surgically and conservatively. After adjusting for confounders, weekend admission was independently and significantly associated with a rise in 30-day mortality (odds ratio (OR) 1.4, 95% confidence interval (CI) 1.02 to 1.9; p = 0.039) for patients undergoing hip fracture surgery. There was no increase in mortality associated with weekend surgery (OR 1.2, 95% CI 0.8 to 1.7; p = 0.39). All hip fracture patients, whether managed surgically or conservatively, were more likely to die as an inpatient when admitted at the weekend (OR 1.4, 95% CI 1.02 to 1.80; p = 0.032), despite our unit having a comparatively low overall inpatient mortality (8.7%). Hip fracture patients admitted over the weekend appear to have a greater risk of death despite having a consultant-led service.

Cite this article: Bone Joint J 2014;96-B:373–8.