Aims. Medial unicompartmental knee arthroplasty (mUKA) is an advised treatment for anteromedial knee osteoarthritis. While long-term survival after mUKA is well described, reported incidences of short-term surgical complications vary and the effect of surgical usage on complications is less established. We aimed to describe the overall occurrence and treatment of surgical complications within 90 days of mUKA, as well as occurrence in high-usage centres compared to low-usage centres. Methods. mUKAs performed in eight fast-track centres from February 2010 to June 2018 were included from the Lundbeck Foundation Centre for Fast-track Hip and Knee Replacement Database. All readmissions within 90 days of surgery underwent chart review and readmissions related to the surgical wound or the prosthesis were recorded. Centres were categorized as high-usage centres when using mUKA in ≥ 20% of annual knee arthroplasties. The occurrence of complications between high- and low-usage centres were compared using Fisher’s exact test. Results. We included 3,757 mUKAs: 2,377 mUKAs from high-usage centres and 1,380 mUKAs from low-usage centres. Surgical complications within 90 days occurred in 69 cases (1.8%), 45 (1.9%) in high-usage centres and 24 (1.7%) in low-usage centres (odds ratio (OR) 1.1 (95% confidence interval (CI) 0.65 to 1.8)). The most frequent complications were periprosthetic joint infections (PJIs) (n = 18; 0.48%), wound-related issues (n = 14; 0.37%), and periprosthetic fractures (n = 13; 0.35%). Bearing dislocations (n = 7; 0.19%) occurred primarily in procedures from high-usage centres. In high-usage centres, seven periprosthetic fractures (0.29%) occurred compared to six (0.43%) in low-usage centres (OR 0.68 (95% CI 0.20 to 2.0)). In high-usage centres, nine PJIs (0.38%) occurred compared to nine (0.65%) in low-usage centres (OR 0.58 (95% CI 0.22 to 1.6)). Conclusion. Surgical complications are rare after fast-track mUKA surgery and with no difference in overall occurrence of surgical complications between high- and low-usage centres, although the risk of some specific surgical complications may favour high-usage centres. Cite this article: Bone Jt Open 2023;4(6):457–462

Aims. The aim of this prospective multicentre study was to describe trends in length of stay and early complications and readmissions following unicompartmental knee arthroplasty (UKA) performed at eight different centres in Denmark using a fast-track protocol and to compare the length of stay between centres with high and low utilization of UKA. Methods. We included data from eight dedicated fast-track centres, all reporting UKAs to the same database, between 2010 and 2018. Complete ( > 99%) data on length of stay, 90-day readmission, and mortality were obtained during the study period. Specific reasons for a length of stay of > two days, length of stay > four days, and 30- and 90-day readmission were recorded. The use of UKA in the different centres was dichotomized into ≥ 20% versus < 20% of arthroplasties which were undertaken being UKAs, and ≥ 52 UKAs versus < 52 UKAs being undertaken annually. Results. A total of 3,927 procedures were included. Length of stay (mean 1.1 days (SD 1.1), median 1 (IQR 0 to 1)) was unchanged during the study period. The proportion of procedures with a length of stay > two days was also largely unchanged during this time. The percentage of patients discharged on the day of surgery varied greatly between centres (0% to 50% (0 to 481)), with centres with high UKA utilization (both usage and volume) having a larger proportion of same-day discharges. The 30- and 90-day readmissions were 166 (4.2%) and 272 (6.9%), respectively; the 90-day mortality was 0.08% (n = 3). Conclusion. Our findings suggest general underutilization of the potential for quicker recovery following UKA in a fast-track setup. Cite this article: Bone Joint J 2020;102-B(9):1167–1175

Bilateral simultaneous total knee replacement (TKR) has been considered by some to be associated with increased morbidity and mortality. Our study analysed the outcome of 150 consecutive, but selected, bilateral simultaneous TKRs and compared them with that of 271 unilateral TKRs in a standardised fast-track setting. The procedures were performed between 2003 and 2009. Apart from staying longer in hospital (mean 4.7 days (2 to 16) versus 3.3 days (1 to 25)) and requiring more blood transfusions, the outcome at three months and two years was similar or better in the bilateral simultaneous TKR group in regard to morbidity, mortality, satisfaction, the range of movement, pain, the use of a walking aid and the ability to return to work and to perform activities of daily living. Bilateral simultaneous TKR can therefore be performed as a fast-track procedure with excellent results

Introduction. Deep venous thrombosis (DVT) is a potentially serious complication after total hip (THA) and knee (TKA) arthroplasty, traditionally justifying aggressive prophylaxis with low molecular weight heparin (LMWH) or direct oral anticoagulants (DOA) at the cost of an increased risk of bleeding. However, fast-track procedures might reduce the DVT risk and decrease the cost-benefit ratio of the current recommendations. The objective of this study was to compare thrombotic and bleeding risk in an unselected population of elective THA and TKA with a fast-track procedure. MATERIAL - METHODS. A series of 1,949 patients were analyzed prospectively. There were 1,136 women and 813 men, with a mean age of 70 years. In particular, 16% were previously treated by antiplatelet agents and 8% by anticoagulants. All patients followed a fast-track procedure including early walking within 24 hours of surgery, and 80% of patients returned home after surgery, with a mean length of stay of 3 days (THA) or 4 days (TKA). The occurrence of a thromboembolic event or hemorrhagic complication has been identified. Results. Out of the 1,110 THAs, 5 thromboembolic events were identified (0.4%): 2 non-fatal pulmonary embolism and 3 DVTs. There was no impact of these complications on the final result. 19 hemorrhagic complications were identified (1.7%): 10 significant haematomas (3 of which were complicated by infection), 9 anemias (with 4 transfusions). Out of the 839 TKAs, 9 thromboembolic events were identified (1.0%): 4 non-fatal pulmonary embolism and 5 DVTs. There was no impact of these complications on the final result. 14 hemorrhagic complications were identified (1.7%): 8 haematomas including 4 reoperations, 6 anemias (with 5 transfusions). Discussion. Thromboembolic complications after elective THA and TKA have virtually disappeared, with a rate of 0.7%. On the other hand, bleeding complications are now more frequent, with a rate of 1.7%. This suggests that the cost-benefit ratio of preventive treatments with LMWH or DOA should be reassessed. Prescribing LMWH or DOA after elective THA and TKA with fast-track procedures exposes the patient to a much higher risk of bleeding than thrombotic risk. The use of aspirin may represent an acceptable compromise in these patients

Introduction. Most western countries have implemented fast-track hip fracture aiming at surgery within 24 hours, since the mortality rate hereafter rises markedly. In Greenland, it is not achievable to operate within 24 hours. Arctic people live in sparsely populated areas and Greenland's population is scattered along the vast coastline. All patients must be chartered to Nuuk by airplane which can take up till several days to weeks, due to logistics and the Arctic weather. This presents a challenge regarding adhering to western guidelines. The operative delay may be acceptable though, as it is the impression that the Greenlandic population survives and endures better than patients of western populations. However, as data are lacking, we aimed to describe mortality among hip fracture patients in Greenland taking frailty and comorbidities into account. Method. All patients with ICD-10 codes DS720, DS721 and DS722 from 2018-2022 were identified as 261 patients diagnosed with hip fractures. Variables including time of diagnosis, time to operation, reasons for delay, ASA-score, Charlson Comorbidity index, time of death, and other possible confounding variables were analyzed. Primary outcome was mortality rates at 30-day post-OP and 1-year post-OP. Results. The average time from fracture to operation was 91.4 hours. In the Danish Cohort (DC) 70,6 % of patient were operated within 24 hours. Overall, 30-day mortality was 9,9 %, and 1-year mortality was 29,4 %, compared to the DC with 10,8 % 30-day mortality and 28,3 % 1-year mortality. Multivariate regression was conducted, showing no statiscal significant increase in mortality, despite extended delay. Conclusion. With no increase in death, the authors find it justifiable that patients in Greenland endure longer delays than the western population. The influence on further adverse effects needs to be investigated as well as causes of survival, but perhaps the Arctic people unveil mechanisms for raised survival among other populations

Fast-track THA and TKA is a dynamic process combining clinical and logistical enhancements to ensure the best outcome for all patients regarding faster early functional recovery and reduced morbidity. Focus is on reducing convalescence by ensuring a smooth pathway with the best available clinical treatment from admission to discharge – and beyond. Main focus areas include pain treatment, mobilization, organizational aspects, traditions, and care principles. Outcome is typically evaluated as: a) length of stay in hospital (LOS), patient satisfaction, and reduced convalescence in the form of earlier achievement of functional milestones; b) safety aspects (reduced morbidity and mortality in the form of complications and readmissions in general and dislocations/manipulations in specific); c) feasibility (can the track be applied to other subgroups of patients, i.e. bilaterals or revisions?); and d) economic savings. Favorable outcomes regarding all these parameters have been documented for fast-track THA and TKA which has also resulted in the development of a Rapid Recovery Programme (Biomet). LOS is now 1–2 days for unselected patients in leading departments with few readmissions, high patient satisfaction and economic savings. In Denmark, the nationwide median LOS is now 4 days and improved logistic features include homogeneous entities, regular staff, high level of continuity, preoperative information including intended LOS, admission on the day of surgery and functional discharge criteria. The improved clinical features include both intraoperative (spinal anesthesia, local infiltration analgesia (LIA), plans for fluid therapy, small standard incisions, no drains, compression bandages and cooling) and postoperative (deep venous thrombosis prophylaxis starting 6–8 hours postoperatively, multimodal opioid-sparing analgesia, early mobilization and discharge when functional criteria are met) facilitating early rehabilitation and discharge. Future challenges include identification of high-pain responders to improve multimodal pain treatment; identification of high-risk patients regarding complications in fast-track set-ups; how to reduce postoperative cognitive dysfunction; how to reduce orthostatic intolerance; and when how and to whom to initiate and give rehabilitation

Purpose. The hip fracture has been increasing as the aging population continues to grow. Hip fracture patients are more susceptible to blood loss and venous thromboembolism (VTE). The objective of this study was to assess the efficacy and safety of tranexamic acid (TXA) in fracture patients undergoing fast-track hemiarthroplasty. Methods. 609 hip fracture patients undergoing hemiarthropalsty from January 2013 to September 2016 were prospectively selected. 289 patients received 15 mg/kg TXA prior to surgery, and the remaining 320 patients received no TXA. All the patients received a fast-track program including nutrition management, blood management, pain management, VTE prophylaxis and early mobilization and early intake. The primary outcome was transfusion requirement, other parameters such as blood loss, hemoglobin (Hb) level, VTE, adverse events and length of hospital stay were also compared. Multivariate logistic regression analysis and meta-analysis were also performed to identify the risk factors of transfusion and confirm the results of current study. Results. Transfusion of at least 1U of erythrocyte blood cell occurred in 25 patients (8.65%) in treatment group and in 77 (24.06%, OR=0.299, p<0.001) in control group. The mean level of Hb on POD 1 (111.70±18.40 g/L) and POD 3 (108.16±17.25 g/L) in TXA group were higher than control group (107.29±18.70 g/L, p= 0.008; 104.22±15.16 g/L, p= 0.005 respectively). More patients get off bed to ambulate within 24 hours after surgery in TXA group (37.02% Vs 26.25%, p= 0.004). And the length of hospital stay was shorter (11.82±4.39 Vs 15.96±7.30, p= 0.003). No statistical significance were detected regarding VTE and other adverse events. Logistic regression analysis showed that the relative odds reduction after adjustment for these covariates was 67% (OR= 0.327, 95%CIs= 0.197 to 0.544) in favor of tranexamic acid. Other risk factors included preoperative hemoglobin level, operation time, VTE prophylaxis. Pooling the data showed that tranexamic acid led to a significant reduction in transfusion (OR= 0.33, 95%CIs= 0.25 to 0.43) without sacrificing safety (OR= 0.70, 95%CIs= 0.25 to 1.97). Conclusion. Tranexamic acid was effective and safe to reduce blood loss and transfusion in geriatric hip fracture patients undergoing fast-track hemiarthroplasty

The incidence of hip fractures is rising, and at the same time the patients are getting increasingly frail and elderly. Patients in Europe have a median hospitalization time of as much as 28 days, and the peri-operative morbidity and mortality is high. 1. Most interventional studies have been unimodal with very heterogeneous results and at present, limited data are available from multimodal intervention according to the established principles of fast-track care. 2. This study has very positive results with a reduction in hospitalization from 21 till 11 days. Anaesthesiological intervention in a fast track regimen must be peri-operative in such a high-risk group of patients. Early operation is probably preferable. 3. Pre-operative regional analgesia potentially reduces cardiovascular morbidity, if instituted immediately after arrival. 4. The effect of regional anaesthesia and postoperative regional analgesia on morbidity and mortality in hip fracture patients may be advantageous. 5. . Postoperative epidural analgesia can be provided without restrictions on patient mobility and rehabilitation, provides superior dynamic pain relief and reducing the influence of pain as a restricting factor on physiotherapy. 6. A potential effect of intra-operative volume optimization has been shown, although the effect on morbidity and mortality is unclear. 7. No information exists for postoperative fluid therapy regimens, but fluid excess is probably important to avoid. 8. Hip fracture patients often suffer from malnutrition at the time of admission and protein and energy supplementation potentially reduces mortality and morbidity. 9. Therefore a short perioperative fasting period combined with aggressive peri-operative oral nutrition and anaesthesia and analgesia techniques, that minimizes catabolism and PONV seems rational. Since mortality and morbidity is so high these patients should be treated in close cooperation between surgeons and anaesthesiologists both in the pre and postoperative phase. 10. , as established practice in other high risk patients. Mortality is not the optimal parameter the for success of intervention in this population, as effects are extremely difficult to document, since as much as 50–75 % of the perioperative mortality may be unrelated to the treatment regimen. 11. . The cumulated evidence for the peri-operative care of this patient group is scarce and fast-track rehabilitation regimens should look to other operational procedures for available evidence. 12. Future research should focus on broadening the evidence for relevant pre-operative optimization, the influence of regional analgesia on rehabilitation potential and optimized peri-operative fluid therapy, transfusion and nutrition regimens

Background

Patients with fractured neck of femur have historically received less attention than they deserve and have high morbidity and mortality. Literature suggests that speed to theatre reduces length of in-patient stay and complications.

Aims

Day-case success rates after primary total hip arthroplasty (THA), total knee arthroplasty (TKA), and medial unicompartmental knee arthroplasty (mUKA) may vary, and detailed data are needed on causes of not being discharged. The aim of this study was to analyze the association between surgical procedure type and successful day-case surgery, and to analyze causes of not being discharged on the day of surgery when eligible and scheduled for day-case THA, TKA, and mUKA.

Purpose

Clinicians need knowledge about early and valid predictors of short-term outcome of patients with hip fracture, to adjust and plan rehabilitation. The concept of multimodal rehabilitation has proven effective. Still, some patients do not regain basic mobility independency in the acute orthopaedic setting. The aim was to examine the predictive value of age, sex, prefracture functional level, mental and health status, and fracture type of in-hospital basic mobility outcome, and discharge destination after hip fracture surgery.

Aims. To investigate the impact of consecutive perioperative care transitions on in-hospital recovery of patients who had primary total knee arthroplasty (TKA) over an 11-year period. Methods. This observational cohort study used electronic health record data from all patients undergoing preoperative screening for primary TKA at a Northern Netherlands hospital between 2009 and 2020. In this timeframe, three perioperative care transitions were divided into four periods: Baseline care (Joint Care, n = 171; May 2009 to August 2010), Function-tailored (n = 404; September 2010 to October 2013), Fast-track (n = 721; November 2013 to May 2018), and Prehabilitation (n = 601; June 2018 to December 2020). In-hospital recovery was measured using inpatient recovery of activities (IROA), length of stay (LOS), and discharge to preoperative living situation (PLS). Multivariable regression models were used to analyze the impact of each perioperative care transition on in-hospital recovery. Results. The four periods analyzed involved 1,853 patients (65.9% female (1,221/1,853); mean age 70.1 years (SD 9.0)). IROA improved significantly with each transition: Function-tailored (0.9 days; p < 0.001 (95% confidence interval (CI) -0.32 to -0.15)), Fast-track (0.6 days; p < 0.001 (95% CI -0.25 to -0.16)), and Prehabilitation (0.4 days; p < 0.001 (95% CI -0.18 to -0.10)). LOS decreased significantly in Function-tailored (1.1 days; p = 0.001 (95% CI -0.30 to -0.06)), Fast-track (0.6 days; p < 0.001 (95% CI -0.21 to -0.05)), and Prehabilitation (0.6 days; p < 0.001 (95%CI -0.27 to -0.11)). Discharge to PLS increased in Function-tailored (77%), Fast-track (91.6%), and Prehabilitation (92.6%). Post-hoc analysis indicated a significant increase after the transition to the Fast-track period (p < 0.001 (95% CI 3.19 to 8.00)). Conclusion. This study highlights the positive impact of different perioperative care procedures on in-hospital recovery of patients undergoing primary TKA. Assessing functional recovery, LOS, and discharge towards PLS consistently, provides hospitals with valuable insights into postoperative recovery. This can potentially aid planning and identifying areas for targeted improvements to optimize patient outcomes. Cite this article: Bone Joint J 2024;106-B(6):573–581

We present detailed information about early morbidity after aseptic revision knee replacement from a nationwide study. All aseptic revision knee replacements undertaken between 1st October 2009 and 30th September 2011 were analysed using the Danish National Patient Registry with additional information from the Danish Knee Arthroplasty Registry. The 1218 revisions involving 1165 patients were subdivided into total revisions, large partial revisions, partial revisions and revisions of unicondylar replacements (UKR revisions). The mean age was 65.0 years (27 to 94) and the median length of hospital stay was four days (interquartile range: 3 to 5), with a 90 days re-admission rate of 9.9%, re-operation rate of 3.5% and mortality rate of 0.2%. The age ranges of 51 to 55 years (p = 0.018), 76 to 80 years (p < 0.001) and ≥ 81 years (p < 0.001) were related to an increased risk of re-admission. The age ranges of 76 to 80 years (p = 0.018) and the large partial revision subgroup (p = 0.073) were related to an increased risk of re-operation. The ages from 76 to 80 years (p < 0.001), age ≥ 81 years (p < 0.001) and surgical time > 120 min (p <  0.001) were related to increased length of hospital stay, whereas the use of a tourniquet (p = 0.008) and surgery in a low volume centre (p = 0.013) were related to shorter length of stay.

In conclusion, we found a similar incidence of early post-operative morbidity after aseptic knee revisions as has been reported after primary procedures. This suggests that a length of hospital stay ≤ four days and discharge home at that time is safe following aseptic knee revision surgery in Denmark.

Cite this article: Bone Joint J 2014;96-B:1649–56.

After implementation of a ‘fast-track’ rehabilitation protocol in our hospital, mean length of hospital stay for primary total hip arthroplasty decreased from 4.6 to 2.9 nights for unselected patients. However, despite this reduction there was still a wide range across the patients’ hospital duration. The purpose of this study was to identify which specific patient characteristics influence length of stay after successful implementation of a ‘fast-track’ rehabilitation protocol. A total of 477 patients (317 female and 160 male, mean age 71.0 years; 39.3 to 92.6, mean BMI 27.0 kg/m²;18.8 to 45.2) who underwent primary total hip arthroplasty between 1 February 2011 and 31 January 2013, were included in this retrospective cohort study. A length of stay greater than the median was considered as an increased duration. Logistic regression analyses were performed to identify potential factors associated with increased durations. Median length of stay was two nights (interquartile range 1), and the mean length of stay 2.9 nights (1 to 75). In all, 266 patients had a length of stay ≤ two nights. Age (odds ratio (OR) 2.46; 95% confidence intervals (CI) 1.72 to 3.51; p <  0.001), living situation (alone vs living together with cohabitants, OR 2.09; 95% CI 1.33 to 3.30; p = 0.002) and approach (anterior approach vs lateral, OR 0.29; 95% CI 0.19 to 0.46; p <  0.001) (posterolateral approach vs lateral, OR 0.24; 95% CI 0.10 to 0.55; p < 0.001) were factors that were significantly associated with increased length of stay in the multivariable logistic regression model.

Cite this article: Bone Joint J 2015;97-B:19–23.

Aims

The primary aim of this study was to investigate the effect of an enhanced recovery program (ERP) on the short-term functional outcome after total hip arthroplasty (THA). Secondary outcomes included its effect on rates of dislocation and mortality.

Data on early morbidity and complications after revision total hip replacement (THR) are limited. The aim of this nationwide study was to describe and quantify early morbidity after aseptic revision THR and relate the morbidity to the extent of the revision surgical procedure. We analysed all aseptic revision THRs from 1st October 2009 to 30th September 2011 using the Danish National Patient Registry, with additional information from the Danish Hip Arthroplasty Registry. There were 1553 procedures (1490 patients) performed in 40 centres and we divided them into total revisions, acetabular component revisions, femoral stem revisions and partial revisions. The mean age of the patients was 70.4 years (25 to 98) and the median hospital stay was five days (interquartile range 3 to 7). Within 90 days of surgery, the readmission rate was 18.3%, mortality rate 1.4%, re-operation rate 6.1%, dislocation rate 7.0% and infection rate 3.0%. There were no differences in these outcomes between high- and low-volume centres. Of all readmissions, 255 (63.9%) were due to ‘surgical’ complications versus 144 (36.1%) ‘medical’ complications. Importantly, we found no differences in early morbidity across the surgical subgroups, despite major differences in the extent and complexity of operations. However, dislocations and the resulting morbidity represent the major challenge for improvement in aseptic revision THR.

Cite this article: Bone Joint J 2014; 96-B:1464–71.

The December 2024 Hip & Pelvis Roundup. 360. looks at: Total hip arthroplasty after femoral neck fractures versus osteoarthritis at one-year follow-up: a comparative, retrospective study; Excellent mid-term survival of a monoblock conical prosthesis in treating atypical and complex femoral anatomy with total hip arthroplasty; Hip arthroscopy for femoroacetabular impingement improves sexual function; Fast-track hip arthroplasty does not increase complication rates; Ten-year experience with same-day discharge outpatient total hip arthroplasty: patient demographics changed, but safe outcomes were maintained

During the last decade primary total hip arthroplasty surgery (THA) has increased with 30% in Sweden. Current law guarantees the patient a right to treatment within 90 days. The public health system has had difficulties meeting the increasing demand. Therefore, in 2012 a systematic review of the patients planned for THA was initiated at Sahlgrenska University Hospital's joint replacement unit. In late 2013 the value-based health care (VBHC) management was introduced in our unit. In 2012 a systematic approach based on the Fast-Track concept was implemented in the joint replacement unit. In 2013 a workgroup consisting of health care professionals involved in the treatment of THA patients was created to improve chosen outcome parameters. During 2011–2016 the number of elective THA has increased from 317 to 486. The cost per patient has decreased from 75,000 SEK to 65,000 SEK. Length of stay has decreased from 5.9 days to 2.5 days. Satisfaction with outcome of surgery one year after THA increased from 76% to 88%. The number of adverse events decreased from 29% to 11%. Number of re-operations within 2 years decreased from 2,7% to 1,9%. Fast-Track and VBHC management was initially received with modest enthusiasm in our unit, and was regarded as means to increase production whilst possibly endanger the well-being of the patients. By using continuous feedback using the data collected it was possible to effectively communicate to patients and caregivers that the patients benefitted from the implementation. VBHC primary aim is to improve patient outcomes and synergetically improve cost and process measurements. This should be appealing to both caregivers and administrators. Focusing on improvement of outcomes after THA combined with VBHC management has contributed to improvement in quality of care and availability of treatment whilst decreasing cost per patient

The outcome after total hip replacement has improved with the development of surgical techniques, better pain management and the introduction of enhanced recovery pathways. These pathways require a multidisciplinary team to manage pre-operative education, multimodal pain control and accelerated rehabilitation. The current economic climate and restricted budgets favour brief hospitalisation while minimising costs. This has put considerable pressure on hospitals to combine excellent results, early functional recovery and shorter admissions. In this review we present an evidence-based summary of some common interventions and methods, including pre-operative patient education, pre-emptive analgesia, local infiltration analgesia, pre-operative nutrition, the use of pulsed electromagnetic fields, peri-operative rehabilitation, wound dressings, different surgical techniques, minimally invasive surgery and fast-track joint replacement units. Cite this article: Bone Joint J 2013;95-B:1587–94

The August 2023 Knee Roundup³⁶⁰ looks at: Curettage and cementation of giant cell tumour of bone: is arthritis a given?; Anterior knee pain following total knee arthroplasty: does the patellar cement-bone interface affect postoperative anterior knee pain?; Nickel allergy and total knee arthroplasty; The use of artificial intelligence for the prediction of periprosthetic joint infection following aseptic revision total knee arthroplasty; Ambulatory unicompartmental knee arthroplasty: development of a patient selection tool using machine learning; Femoral asymmetry: a missing piece in knee alignment; Needle arthroscopy – a benefit to patients in the outpatient setting; Can lateral unicompartmental knees be done in a day-case setting?