Background

The current average tariff of a total knee replacement (TKR) is £5500. The approximate cost of each knee prosthesis is £2500. Therefore, length of patient stay (LOS) and the cost of patient rehabilitation influence the total costs significantly. Previous studies have shown a mean LOS of between 5 and 9.4 days for patients undergoing primary unilateral TKR but none looked at the factors influencing length of stay following bilateral primary total knee replacements (BTKR) at the same sitting.

Introduction and Objective. Lower limb fractures are amongst the most common surgically managed orthopaedic injuries, with open reduction and internal fixation (ORIF) as the conventional method of treatment of the fibula. In recent years, dedicated intramedullary implants have emerged for fibula fixation in tandem with the move towards minimally invasive surgery in high-risk patients. This is the largest multicentre review to date with the aim of establishing the clinical outcomes following intramedullary nail (IMN) fixation of the fibula and to identify the absolute indication for fibula IMN fixation. Materials and Methods. A retrospective study of adult patients in all UK hospitals, who underwent fibula nail fixation between 01/01/2018 and 31/10/2020 was performed. Primary outcome measures included time to union, infection rate, other post-operative complications associated with the fixation and length of hospital stay. The secondary outcome measure was to identify the indication for fibula nailing. Data tabulation was performed using Microsoft Excel and analysis was performed using SPSS Version 23 (SPSS Statistics). Results. 2 Major Trauma Centres (MTCs) and 9 Trauma Units (TUs) were eligible for inclusion. 102 patients were included and 91% were classified as ankle fractures of 68% (n=69) were Weber B, 24% (n=24) Weber C and 8% (n=9) were either distal tibial fractures with an associated fibula fracture or pilon fractures. The mean age was 64 years of which 45 were male patients and 57 were female. The average BMI was 30.03kg/m. 2. and 44% of patients were ASA 3. 74% of patients had poor pre-op skin condition including swelling and open wounds. The calculated infection rate for fibula nail was 4.9% and metal-work complication rate was 4.9%. The average time to union was 13 weeks and length of inpatient stay was 15 days (SD +/− 12 days). Conclusions. MEFNO has demonstrated that fibula nail is an ideal implant in patients who have a physiologically higher risk of surgery, poor skin condition and a complex fracture pattern. The time to union, complication and infection risks are lower than that reported in literature for ankle ORIFs

Background. Intracapsular neck of femur fractures are one of the most common injuries seen in Orthopaedics. When the fracture is amenable to internal fixation there are 2 main treatment options, namely multiple cannulated hip screws (MCS) and 2-hole sliding hip screws (SHS). In this retrospective study we examine the outcomes associated with these two methods of internal fixation. At present there is little consensus regarding which treatment should be used. Methods. 161 patients were found to have suffered intracapsular neck of femur fracture treated with either SHS or MCS fixation over a 5 year period from April 2009 to April 2014, allowing at least 1 year follow up following injury. The patients imaging and clinical notes were then reviewed to ascertain the outcome of their treatment and any complications. Results. 93 patients were treated with a sliding hip screw compared to 68 that had been treated with cannulated screws. To ensure the fractures in each group were comparable in terms of fracture severity they were classified using gardens and pauwels score. The mean age of the group treated with SHS was 75.15 years, 7.69 years higher than those treated with MCS. The mean length of inpatient stay was 4.7 days longer for patients treated with sliding hip screws than those treated with cannulated screws, which is significantly more than would be predicted by age difference alone. Further patients were excluded for analysis of failure rate if they had not been sufficiently followed up, leaving 122 patients, 58 treated with MCS and 64 with SHS. A significantly higher (p=0.0136) proportion of patients treated with SHS (32%) suffered failure of their fixation compared to those treated with MCS (10%). The SHS group was further classified by whether or not a permanent derotation screw was employed. The use of a derotation screw provided protection against failure with a number needed to treat of 3.82, decreasing the failure rate to 14% which was not significantly more than the failure rate for MCS. Conclusions. We recommend that the first choice treatment for intracapsular neck of femur fractures amenable to internal fixation should be cannulated screws due to a lower rate of failure and shorter length of inpatient stay. If a surgeon has a strong preference for sliding hip screw we strongly recommend inserting a permanent derotation screw

Background. Post-operative acute kidney injury is significant complication following surgery. Patients who develop AKI have an increased risk for progression into chronic kidney disease, end-stage renal failure and increased mortality risk. The patient outcomes following total knee replacement (TKR), who develop AKI has been a topic of interest in recent years as it may have patient and medicolegal implications. Nevertheless, there are no studies looking at the incidence, risk factors and outcomes of AKI following bilateral TKRs at the same sitting. Objectives. To determine the incidence, risk factors and outcomes of post-operative AKI following bilateral TKRs surgery at the same sitting. Methods. This was a retrospective single-centre study performed at the Princess Royal Hospital, which performed a total of 25 BTKR. The incidence, Surgical and patient risk factors were recorded and analysed. Results. The incidence of AKI as defined by NICE guidelines following bilateral TKRs was 20%. 16% (4 patients) had stage 1 and 4% (1 patient) had stage 2 AKI. The mean change in Creatinine between pre- and post-operative blood tests was +19μmol/L. There was a strong significant correlation between CKD and AKI (r=0.75, P<0.05). Furthermore, a moderate correlation was found between higher BMI and pre-operative Charlson index and AKI. AKI did not have an effect on the length of inpatient stay with the mean inpatient length of stay for patients who had an AKI of 10 days compared to 11days for those who did not. All AKIs were resolved within 72 hours. There were no associated mortalities with AKI. Conclusion. The incidence of AKI following bilateral TKR was 20%. Pre-operative chronic kidney disease as well as having a higher BMI were identified as risk factors for developing AKI. Pre-operative CKD optimisation and careful adequate hydration intra-operatively should be considered in these patients. AKI was not associated with an increased length of stay or mortality in our study

Intraoperative cell salvage involves the collection of blood directly from the operative field. The purpose of this study was to determine if its use reduces the need for postoperative allogenic blood transfusion, assess any adverse events and its effect on duration of postoperative stay in primary hip arthroplasty. We prospectively examined the effect of intraoperative cell salvage on the need for postoperative allogenic blood transfusion. Between February 2009 and August 2010, a total of 77 patients who underwent primary total hip arthroplasty were included in the study, under the care of the senior author (KB). All patients had a diagnosis of osteoarthritis. Intraoperative cell salvage was used in 38 patients and not used in 39 patients. We prospectively collected data on patient demographics, ASA grade, preoperative and postoperative haematological features, number of units of packed red cells transfused and the volume of intraoperative reinfused cell salvaged blood was. Total inpatient stay and any postoperative adverse events were recorded. No patients in the cell salvage group required postoperative allogenic blood transfusion compared to three patients (7.7%) in the conventional group. Postoperative decrease in haemoglobin was less in the cell salvage group (2.57 vs. 3.3 g/dL). The mean length of postoperative inpatient stay was shorter in the cell salvage group (5.1 vs. 6.41 days). Three patients in the cell salvage group had adverse events (1 UTI, 1 hyponatraemia, 1 colonic pseudo-obstruction). Three patients in the conventional group experienced adverse events (2 superficial wound infections, 1 DVT). An average of 361mls of cell salvaged blood was reinfused (110–900mls). We have found that the use of intraoperative cell salvage in patients undergoing primary total hip arthroplasty reduces the need for post operative allogenic blood transfusion with no increase in adverse events when compared to conventional measures of blood preserving techniques

Physiotherapy is generally accepted as an important component in the care pathway surrounding total knee replacement. Therapy interventions can be delivered prior to surgery, as part of the inpatient stay, and post-operation through outpatient appointments. Though ‘physiotherapy’ is generally promoted there is considerable national and international variation in actual therapy provision. Specific rehabilitation protocols are strongly entrenched at individual physiotherapy departments however the wider efficacy of varying physiotherapeutic interventions is poorly established. This uncertainty as to effectiveness of physiotherapy makes it difficult for commissioning organisations, healthcare providers, and patients to make decisions as to what therapy is ‘needed’ and therefore the correct level and mechanism of funding for such services. This talk will explore the variation in physiotherapy service provision and evidence for different interventions surrounding total knee replacement

Acetabular fractures in the elderly are associated with high levels of morbidity and mortality. Conservative management is reserved for those unfit for extensive reconstruction, or those who achieve ‘secondary congruence' of a complex fracture. We present demographic data and the results of conservative management in patients over 65 years of age. The Fracture Outcome Research Database (FORD) at our unit was interrogated for all patients over 65 years, who had sustained an acetabular fracture between June 2008 and June 2016. 410 patients were identified. Following exclusions, thirty-two patients were included for analysis. They had a mean age of 80 (66–91), and a mean ASA equivalent score of 3.1 (2–4). Mean follow up was five (1–9) years. Twenty-five patients lived in their own home and seven in a nursing home. Thirty had low energy injures, two high energy. Twenty-four (75%) had anterior column posterior hemitransverse fractures, seven (22%) had associated both column and one (3%) had a T-type fracture. The mean length of inpatient stay was 43 days (4–140). Maximum post-operative mobility was limited to a hoist in eight (25%), a frame with or without assistance in 15 (47%), a stick in five (16%) and independence in four (13%). Thirty-day mortality was 6%- and one-year mortality 22%. The data demonstrates that conservative treatment in this cohort leads to long inpatient stays, poor mobility and significant levels of mortality. Complex reconstruction remains demanding on both surgeon and patient. Innovative ways of managing these patients are needed to improve outcomes

Introduction. Despite recent national advances in the care for the hip fracture patient, significant morbidity and mortality persists. Some of this morbidity is attributable to the analgesia provided in the hospital setting. The National Institute of Clinical Excellence recommends the use of simple oral analgesia including opioids, with fascia-iliac blocks used as an adjunct. Literature review reveals a paucity of evidence on this topic. The aim of this study was to evaluate the efficacy of fascia iliac blocks through analysis of pre and post-operative opioid usage, post-operative delirium, time to bowel opening and naloxone use. Methods. A retrospective study was performed between September-December 2013. Inclusion criteria were determined. 41 patients who received spinal anaesthesia alone and 41 patients who received spinal anaesthesia and a fascia-iliac block were included. Results. Patients who received a fascia-iliac block received significantly less post-operative and total analgesia (p=0.04, p=0.03), had lower rates of delirium (p=0.03) and those patients which were discharged directly home had a shorter inpatient stay (p=0.03). No patients who received a fascia-iliac block needed naloxone to reverse opioid toxicity, whilst two non fascia iliac block patients did. Conclusions. Fascia iliac blocks either given in A&E or at the time of spinal anaesthesia are a useful adjunct to provide analgesia in the hip fracture patient. The John Radcliffe hospital aims to incorporate fascia-iliac blocks into the care pathway for the hip fracture patient

Background. The advantages of treatment by open reduction and internal fixation for intertrochanteric fractures of the proximal femur have been well known for several decades. Failure of fixation can result in revision surgery, prolonged inpatient stay and has major socio-economic consequences. There are many new devices on the market to help deal with this problem. Expandable hip screw (EHS) is one such device, which is an expanding bolt that may offer superior fixation in osteoporotic bone compared to the standard dynamic hip screw (DHS) type device. Methods. Static axial compression tests with elastic deformation of the specimens were performed with a crosshead speed of 10 mm/min to determine stiffness of testing was performed with 3 cycles from 0 N to 250 N, 3 cycles from 0 N to 500 N, 3 cycles from 0 N to 750 N and 3 cycles from 0 N to 1000 N with a holding time of 10 s per test cycle. Displacement control was apply the pullout strength with a velocity of 1mm/sec. The ability to resist rotation about the axis of a lag screw is of critical importance particularly when the fracture line is perpendicular, or nearly perpendicular, to the femoral neck. Implants were subjected to a rotation of 1 degree/sec and peak torque values were recorded. Results. The mean axial cyclic loading DHS showed higher stiffness value than EHS. The mean stiffness achieved at pullout test in the EHS and DHS groups were 587.8N/mm and, 334.1N/mm respectively (p<0.05). The peak torque for the EHS device was significantly greater than the torque for the DHS with torque values of 4.56 Nm/degree and 2.97 Nm/degree, respectively (p<0.05). Conclusions. The EHS device demonstrated superior resistance to pullout and torsion greater loads compared to the DHS in an unstable fracture model. However, axial cyclic loading demonstrate lower strength, by optimising the size of device will perform. Level of Evidence. Level 5

Abstract. Objective. In this systematic review we aim to analyse the economical impact of using Negative Pressure Wound Therapy (NPWT) in primary total knee arthroplasty (TKA). Methods. Four medical electronic databases were searched. Eligible studies included those investigating the costs of NPWT in primary TKA. Exclusion criteria included studies investigating cost of NPWT not related to primary TKA. We also excluded studies with poor scientific methodology. We retrieved and analysed data on dressing costs and hospital length of stay (LOS). Results. Three studies (359 patients) reported on dressing and associated health care costs, and two further studies (330 patients) reported on hospital LOS in primary TKA. The cost of NPWT ranged between £125 and £196; with an average cost of £155, compared to £23 for the regular surgical dressing. The hospital LOS in NWPT patients ranged from 1.9 – 3.8 days, while LOS in patients managed with regular surgical dressing ranged between 2.3 – 4.7 days. The hospital LOS accounted for delayed discharge due to wound complications. Any extended LOS secondary to medical comorbidities or for other reasons were not included here. Conclusion. Our pooled analysis found a decrease in hospital LOS from wound related problems when using NWPT instead of regular dressings after accounting for other variables responsible for LOS. If the mean cost of overnight inpatient hospital stay for elective TKA is estimated as £275, the range of overnight admission cost for one TKA patient would be £522 - £1045 when NPWT dressing is used, and £632.5 - £1292 when using regular dressings. The cost savings from reduced LOS amounts to £110 - £247 per patient when NPWT is used. We hypothesize that in primary TKA patients with high risk of wound related problems that may delay discharge from hospital, there may be an overall cost saving when using NWPT dressings. Declaration of Interest. (b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project

At our district general hospital in the southwest of England, around 694 total knee replacements (TKR) are performed annually. Since spring 2013 we have been using an enhanced recovery protocol for all TKR patients, yet we have neither assessed compliance with the protocol nor whether its implementation has made a discernible and measurable difference to the delivery of care in this patient population. Enhanced recovery after surgery (ERAS) protocols are multi-modal care pathways designed to aid recovery. They are based on best evidence and promote a multi-disciplinary approach which standardises care and encompasses nutrition, analgesia and early mobilisation throughout the pre, intra and postoperative phases of an inpatient stay. ERAS has been found to reduce length of stay (LOS), readmission rates and analgesic requirements following surgery. 1, 2, 3. Additionally, they have been shown to improve range of knee movement following TKR and improve mobility, patient satisfaction whilst reducing mortality and morbidity. 4, 5, 6. With these benefits in mind, we sought to investigate how well our trauma and orthopaedic department was complying with a local ERAS protocol and whether we could replicate the benefits seen within the literature. Following approval from our local audit office in September 2015 we generated a patient list of elective TKR patients under the same surgeon before and after the implementation of the ERAS protocol. Using discharge summaries and patient notes we extracted data for 39 patients operated on prior to the ERAS implementation between January 2011 and December 2012 and 27 patients following its introduction between January 2014 and September 2015. Data collected included length of stay, time to discharge from inpatient physiotherapy and use of analgesia and antiemetics. Alongside this we audited the compliance with all facets of the local ERAS protocol. There was no statistically significant difference between the 2 groups in terms of demographics or pre-operative morbidity. Overall compliance with the ERAS protocol was good but there was some variability, especially with intraoperative medication and type of anaesthesia which was likely due to individual patient factors. Compliance with postoperative analgesia was especially good with 93% of patients receiving all 4 suggested analgesics within the ERAS group. Length of stay (LOS) was significantly reduced by 0.5 days per patient (p value < 0.4). Overall compliance with the ERAS protocol was good but there was some variability, especially with intraoperative medication and type of anaesthesia, which was likely due to individual patient factors. Compliance with postoperative analgesia was especially good with 93% of patients receiving all suggested analgesics within the ERAS group. In terms of LOS, we found a statistically significant difference between the pre-ERAS and ERAS group of 0.5 days per patient. Within the context of our DGH, a 0.5 day reduction in LOS translates to around 350 bed days per year and a potential saving of GBP 105,000 (EUR 132,000) making this a clinically significant finding

We aim to compare post-operative length of stay and cardiopulmonary morbidity in patients randomised to either navigated or conventional total knee arthroplasty (TKA). Patients undergoing primary TKA for osteoarthritis were prospectively assigned randomly to either navigation-guided or control groups and blinded to this. All patients received a PFC implant (DePuy, Warsaw, IN). In the control group the standard femoral intramedullary and tibial extramedullary alignment rod was used. In the navigation group, the BrainLab (Munich, Germany) navigation system was used. All operations were carried out by one of two consultant orthopaedic knee surgeons. Length of post operative hospital stay and the development of cardiopulmonary complication were recorded and groups compared. 100 patients were recruited (55 control vs 45 navigated). Patient demographics were similar in both groups. Mean length of stay was 7 days in the control group (range 3-101), 5 days in the navigation group (range 3-10). The mode was 4 days in both groups. 7 patients (13%) stayed for >7 days in the control group, 3 patients (7%) stayed >7 days in the navigation group(p=0.339). 4 patients(7%) required >10 days inpatient stay in the control group, 0 patients required to stay in hospital for longer than 10 days in the navigation group(p=0.069). The causes for the length of stay exceeding 10 days were pulmonary embolus in 3 patients, and chest infection in 1 patient. Patients undergoing navigation-guided TKA required shorter post-operative inpatient stays than those undergoing arthroplasty using conventional techniques. Fewer patients in the navigation group required stays longer than 7 or 10 days. The difference in post-operative stay was associated with fewer respiratory complications in the navigated group

Summary Statement. Navigated total knee arthroplasty (TKA) is becoming increasingly popular in the United States. Compared to traditional unnavigated TKA, the use of navigation is associated with decreased blood transfusions and shorter hospital stays. Introduction. Navigated total knee arthroplasty (TKA) is a recent modification to standard TKA with many purported benefits in regards to component positioning. Controversy currently exists though regarding its clinical benefits. The purpose of this study was to assess recent national trends in navigated and unnavigated total knee arthroplasty and to evaluate perioperative outcomes for each group. Methods. International Classification of Disease - 9th Revision (ICD-9) procedure codes were used to search the National Hospital Discharge Survey (NHDS) for all patients admitted to US hospitals after navigated and unnavigated TKA for each year between 2005 and 2010. Data regarding patient demographics, hospitalization length, discharge disposition, blood transfusions, deep vein thrombosis, pulmonary embolism, mortality, and hospital location were gathered from the NHDS. Trends were evaluated by linear regression with Pearson's correlation coefficient (r) and statistical comparisons were made using Student's t-test, z-test for proportions, and chi-square analysis with a significance level of 0.05. Results. 22,443 patients admitted for TKA were identified. 578 (2.6%) of these patients had a TKA utilizing navigation. After adjusting for fluctuations in annual TKA performed, the use of navigation in TKA demonstrated a strong positive correlation with time (r=0.71), significantly increasing from an average utilization rate of 2.2% between 2005–2007 to 3.2% between 2008–2010 (p<0.01). The location of the hospital was found to significantly impact the utilization of navigation, with the lowest rate seen in the Midwest region (2.0%) of the US and the highest rate seen in the South region (3.0%). The mean age of navigated patients was 66.0 years. This group included 211 men and 367 women. The unnavigated group had a mean patient age that was insignificantly higher at 66.4 years (p=0.37) and included 7,815 men and 14,047 women. Gender was also not significantly different (p=0.71) between those with navigated TKA and those with unnavigated TKA. The number of medical co-morbidities was significantly higher in those with navigation (mean 5.4 diagnoses) than those without navigation (mean 5.1 diagnoses, p=0.01). Average hospitalization length also varied based on navigation status, with significantly shorter stays for those with navigation (3.3 days, range 1–11) compared to those without (3.6 days, range 1–73, p<0.01). The rate of blood transfusion was significantly lower in the navigated group (13.0%) versus the unnavigated group (17.4%, p<0.01). There was no difference in the rate of deep vein thrombosis (0.69% vs 0.53%, p=0.64) or pulmonary embolism (0.17% vs 0.47%, p=0.10). Mortality was also not significantly different for navigated TKA (0.17%) when compared to unnavigated TKA (0.08%, p=0.61). Discharge disposition did not significantly vary based on navigation status either, with 65.5% of navigated patients and 67.0% of unnavigated patients able to go directly home (p=0.55) after their inpatient stay. Discussion/Conclusion. This study demonstrates that the use of navigated TKA in the US is rising. Additionally, despite having more medical co-mobidities, the navigated population required less blood transfusions and shorter lengths of stay. Interestingly, navigation utilization demonstrated variability based on hospital region. The reasons for this are not immediately clear, but may be related to differences in regional training

Summary Statement. Pulmonary embolism (PE) after total knee arthroplasty can have a significant impact on patient outcomes and healthcare costs. Efforts to prevent or minimise PE over the last 10 years have not had a significant impact on its occurrence at the national level. Introduction. Pulmonary embolism (PE) is a rare but known potentially devastating complication of total knee arthroplasty (TKA). Significant healthcare resources and pharmaceutical research has been recently focused on preventing this complication but limited data exists regarding the early results of this great effort. The purpose of this study was to assess recent national trends in PE occurrence after TKA and evaluate patient outcomes related to this adverse event. Methods. International Classification of Disease - 9th Revision (ICD-9) procedure codes were used to search the National Hospital Discharge Survey (NHDS) for all patients admitted to US hospitals after primary TKA for each year between 2001 and 2010. ICD-9 diagnosis codes were then used to identify patients from this population who developed an acute PE during the same admission. Data regarding patient demographics, hospitalization length, discharge disposition, deep vein thrombosis, mortality, and hospital size/location were gathered from the NHDS. Trends were evaluated by linear regression with Pearson's correlation coefficient (r) and statistical comparisons were made using Student's t-test, z-test for proportions, and chi-square analysis with a significance level of 0.05. Results. 35,220 patients admitted for a primary TKA were identified. 159 (0.045%) of these patients developed an acute PE during the same admission. After adjusting for fluctuations in annual TKA performed, the development of PE after TKA demonstrated a weak negative correlation with time (r=0.17), insignificantly decreasing from an average rate of 0.049% between 2001–2005 to 0.041% between 2006–2010 (p=0.26). The size of the hospital was found to significantly impact the incidence of PE and primary TKA, with the lowest rate seen in hospitals under 100 beds (0.23%) and the highest rate seen in those with over 500 beds (0.65%, p=0.01). No significant differences in PE incidence were noted based on US region (p=0.38). The mean age of patients with PE was 67.7 years. This group included 54 men and 105 women. The non-PE group had a mean patient age that was insignificantly lower at 66.6 years (p=0.21) and included 12,450 men and 22,611 women. Gender was also not significantly different (p=0.68) between those with PE and those without PE. The number of medical co-morbidities was significantly higher in those with PE (mean 6.42 diagnoses) than those without PE (mean 4.89 diagnoses, p<0.01). Average hospitalization length also varied based on PE status, with significantly longer stays for those with PE (8.2 days, range 2–53) compared to those without PE (3.7 days, range 1–95, p<0.01). The rate of deep vein thrombosis was higher in the PE group (12.7%) versus the non-PE group (0.48%, p<0.01). Mortality was also significantly higher for the PE group (3.9%) compared to the non-PE group (0.09%, p<0.01). Discharge disposition did not significantly vary based on PE status, with 61.5% of PE and 64.0% of non-PE patients able to go directly home (p=0.59) after their inpatient stay. Discussion/Conclusion. This study demonstrates that PE can have a significant impact on patient outcomes and healthcare costs, with an associated 43-fold increase in mortality and a doubling of the inpatient admission duration. Additionally, although the risk of PE after primary TKA remains rare, it still persists. Efforts to prevent or minimise this complication over the last 10 years have not had a significant impact on its occurrence at the national level. This risk of PE appears to be greatest in patients with multiple medical co-morbidities and established DVTs. Interestingly, the PE rate also demonstrated variability based on hospital size. The reasons for this are not clear, but we suspect larger hospitals are more likely to be tertiary-care centers and thus care for more medically-complex patients

In this study a combination of autologous chondrocyte implantation (ACI) and the osteochondral autograft transfer system (OATS) was used and evaluated as a treatment option for the repair of large areas of degenerative articular cartilage. We present the results at three years post-operatively. Osteochondral cores were used to restore the contour of articular cartilage in 13 patients with large lesions of the lateral femoral condyle (n = 5), medial femoral condyle (n = 7) and patella (n = 1). Autologous cultured chondrocytes were injected underneath a periosteal patch covering the cores. After one year, the patients had a significant improvement in their symptoms and after three years this level of improvement was maintained in ten of the 13 patients. Arthroscopic examination revealed that the osteochondral cores became well integrated with the surrounding cartilage. We conclude that the hybrid ACI/OATS technique provides a promising surgical approach for the treatment of patients with large degenerative osteochondral defects.