Primary total hip replacement (THR) is a successful and common operation which orthopaedic trainees must demonstrate competence in prior to completion of training. This study aimed to determine the impact of operating surgeon grade and level of supervision on the incidence of 1-year patient mortality and all-cause revision following elective primary THR in a large UK training centre. National Joint Registry (NJR) data for all elective primary THR performed in a single University Teaching Hospital from 2005–2020 were used, with analysis performed on the 15-year dataset divided into 5-year temporal periods (B1 2005–2010, B2 2010–2015, B3 2015–2020). Outcome measures were mortality and revision surgery at one year, in relation to lead surgeon grade, and level of supervision for trainee-led operations. 9999 eligible primary THR were undertaken, of which 5526 (55.3%) were consultant led (CL), and 4473 (44.7%) trainees led (TL). Of TL, 2404 (53.7%) were non-consultant supervised (TU), and 2069 (46.3%) consultant supervised (TS). The incidence of 1-year patient mortality was 2.05% (n=205), and all-cause revision was 1.11% (n=111). There was no difference in 1-year mortality between TL (n=82, 1.8%) and CL (n=123, 2.2%) operations (p=0.20, OR 0.78, CI 0.55–1.10). The incidence of 1-year revision was not different for TL (n=56, 1.3%) and CL (n=55, 1.0%) operations (p=0.15, OR 1.37, CI 0.89–2.09). Overall, there was no temporal change for either outcome measure between TL or CL operations. A significant increase in revision within 1-year was observed in B3 between TU (n=17, 2.7%) compared to CL (n=17, 1.0%) operations (p=0.005, OR 2.81, CI 1.35–5.87). We found no difference in 1-year mortality or 1-year all-cause revision rate between trainee-led primary THR and consultant-led operations over the entire fifteen-year period. However, unsupervised trainee led THR in the most recent 5-year block (2015–2020) has a significantly increased risk of early revision, mainly due to instability and prosthetic joint infection. This suggests that modern surgical training is having a detrimental effect on THR patient outcomes. More research is needed to understand the reasons if this trend is to be reversed.
Accurate orientation of the acetabular component during a total hip replacement is critical for optimising patient function, increasing the longevity of components, and reducing the risk of complications. This study aimed to determine the validity of a novel VR platform (AescularVR) in assessing acetabular component orientation in a simulated model used in surgical training. The AescularVR platform was developed using the HTC Vive® VR system hardware, including wireless trackers attached to the surgical instruments and pelvic sawbone. Following calibration, data on the relative position of both trackers are used to determine the acetabular cup orientation (version and inclination). The acetabular cup was manually implanted across a range of orientations representative of those expected intra-operatively. Simultaneous readings from the Vicon® optical motion capture system were used as the ‘gold standard’ for comparison. Correlation and agreement between these two methods was determined using Bland-Altman plots, Pearson's correlation co-efficient, and linear regression modelling.Abstract
Objectives
Methods
Current work-hour restrictions and cost pressures have highlighted the limitations of apprenticeship-based learning, and led to the development of alternative methods to improve the skills of orthopaedic trainees outside of the clinical environment. These methods include using synthetic bones and simulators in the laboratory setting. Educational theory highlights the importance of context for effective learning, yet full-immersion simulation facilities are prohibitively expensive. This study explored the concept of contextualised training day in trauma & orthopaedics. Fifteen novice surgeons provided feedback after completing three teaching modules: OSCE-style Problem-based Learning of Orthopaedic Trauma in the Fracture Clinic Setting, utilising an actor and radiographs to teach history, examination, diagnostic and management skills The positioning, preparing and draping of a patient, and Examination under anaesthesia (EUA) for arthroscopic knee surgery, utilising an operating table and theatre equipment to teach procedural and examination skills Simulator based training for diagnostic shoulder and knee arthroscopy; and Bankart repair, utilising arthroscopic stack and synthetic joint models to develop arthroscopic motor skill and procedural knowledgeIntroduction
Methods
Restrictions placed on the working hours of doctors have led to increasing time-pressures on surgical training. Consequently, there has been growing interest in developing new techniques to teach and assess technical skills. The primary aim of this study was to determine whether a novel set of visual parameters assessing visuospatial ability, fine motor dexterity and gaze control could objectively distinguish between varying levels of arthroscopic experience. The secondary aim was to evaluate the correlations between these new parameters and previously established technical skill assessment methods. 27 subjects were divided into a “novice” group (n=7), “trainee” group (n=15) and expert group (n=5) based on previous arthroscopic experience. All subjects performed a diagnostic knee arthroscopy task on a simulator. Their performance was assessed using new simple visual parameters that included “prevalence of instrument loss,” “triangulation time” and “prevalence of look downs”. In addition, performance was also evaluated using previously validated technical skill assessment methods (a global rating scale and motion analysis).Introduction
Methods
Motion analysis is a validated method of assessing technical dexterity within surgical skills centers. A more accessible and cost-effective method of skills assessment is to use a global rating scale (GRS). We aimed to perform a validation experiment to compare an arthroscopic GRS against motion analysis for monitoring orthopaedic trainees learning simulated arthroscopic meniscal repairs. An arthroscopic meniscal repair task on a knee simulator was set up in a bioskills laboratory. Nineteen orthopaedic trainees with no experience of meniscal repair were recruited and their performance assessed whilst undertaking a standardized meniscal repair on 12 occasions. An arthroscopic GRS, assessing parameters such as “depth perception,” “bimanual dexterity,” “instrument handling,” and “final product analysis” was used to evaluate technical skill. Performance was assessed blindly by watching video recordings of the arthroscopic tasks. Dexterity analysis was performed using a motion analysis tracking system which measured “time taken,” “total path length of the subject's hands,” and “number of hand movements”.Introduction
Methods
Technical skill is an essential domain of surgical competency. Arthroscopic surgery forms a particularly challenging subset of these skills. The innate ability to acquire these skills is not fully understood. The aim of this study was to investigate the innate arthroscopic skills and learning curve patterns of medical students - our future surgeons. Two arthroscopic tasks (one shoulder and one knee) were set up in a bioskills laboratory to represent core skills required for arthroscopic training. Twenty medical students with no previous arthroscopic surgery experience were recruited and their performance assessed whilst undertaking each task on 30 occasions. The primary outcome variable was success or failure. Individuals were assessed as ‘competent’ if they stabilised their learning curve within 20 episodes. The secondary outcome measure was an objective assessment of technical dexterity using a validated Motion Analysis system (time taken to complete tasks, total path length of the subject's hands, and number of hand movements).Background
Methods
The ability to learn arthroscopic surgery is an important aspect of modern day orthopaedic surgery. Knowing that variation in innate ability exists amongst medical students, the aim of this study was to investigate the effect of training on the arthroscopic surgical performance of our future orthopaedic surgeons (medical students). Two arthroscopic tasks (one shoulder and one knee) were set up in a bioskills laboratory to represent core skills required for arthroscopic training. Thirty three medical students with no previous arthroscopic surgery experience were randomised to a ‘Trained’ (n=16) and ‘Non-trained’ (n=17) cohort. Both groups watched an instructional video. The Trained cohort also received specific training on the tasks prior to their first episode. Thirty episodes of each task were then undertaken. The primary outcome variable was success or failure. Individuals were assessed as ‘competent’ if they stabilised their learning curve within 20 episodes. The secondary outcome measure was an objective assessment of technical dexterity using a validated Motion Analysis system (time taken to complete tasks, total path length of the subject's hands, and number of hand movements).Background
Methods
Degenerative disorders of tendons present an enormous clinical challenge. They are extremely common, prone to recur and existing medical and surgical treatments are generally unsatisfactory. Eccentric, but not concentric, exercises have been shown to be effective in managing tendinopathy of the Achilles tendon and of the mid-portion of the Achilles tendon in particular. There has been much speculation on why eccentric exercises are effective. This talk will highlight the theories and evidence behind why eccentric exercises are effective. An understanding of why eccentric exercises are effective should inform best clinical practice on rehabilitation of tendinopathy. This talk will also discuss limitations of eccentric exercises and highlight areas where future research is needed.
To investigate the effect of lab-based simulator training, on the ability of surgical trainees to perform diagnostic knee arthroscopy. 20 orthopaedic SHOs with minimal arthroscopic experience were randomised to 2 groups. 10 received a fixed protocol of simulator based arthroscopic skills training using a bench-top knee model. Learning curves were clearly demonstrated using motion analysis equipment to monitor performance. All 20 then spent an operating list with a blinded consultant trainer. They received instruction and demonstration of diagnostic knee arthroscopy before performing the procedure independently. Their performance was assessed using the intra-operative section of the Orthopaedic Competence Assessment Project (OCAP) procedure based assessment (PBA) protocol for diagnostic arthroscopy. Performance was further quantified with a ten point global rating assessment scale.Objective
Method
The aim of this study was to find evidence of tissue hypoxia and apoptosis (programmed cell death) have on a human model of rotator cuff failure. We studied twenty seven patients with no tear mild impingment (3), no tear moderate impingment (3), no tear severe impingment (3), partial tear (3), small tear (3), moderate tear (3), large tear (3), massive tear (3) and control (3) who were undergoing shoulder arthroscopy, subacromial decompression and potential rotator cuff repair. A supraspinatus tendon biopsy was taken during debridement/repair on all cases (ethics number C01.071). Control tendon was obtained from the subscapularis tendon of patients undergoing stabilization surgery. Biopsies were analysed using two immunocytological techniques. A monoclonal antibody against BNIP-3 (a pro-apoptotic marker of hypoxia) and TUNEL (an apoptotic marker). An immunofluorescent nuclear counterstain DAPI (4 6-Diamidino-2-phenylindole dihy-drochloride) was used to stain all cells. Positive cells and total cell number were then counted in 10 high powered fields per section. The results showed a significant increase in BNIP-3 expression in the cuff tears compared with intact tendons. This increase was least in the massive tears. Apoptosis increases from mild impingement to massive cuff tears (mean 7.3% to 21%)
The aim of this study was to understand the role tissue hypoxia and apoptosis have on a human model of rotator cuff failure. We studied twenty seven patients with no tear mild impingment (3), no tear moderate impingment (3), no tear severe impingment (3), partial tear (3), small tear (3), moderate tear (3), large tear (3), massive tear (3) and control (3). A supraspinatus tendon biopsy was taken during debridement/repair in all cases (ethics no. C01.071). Control tendon was obtained from the subscapularis tendon of patients undergoing stabilization surgery. Biopsies were analysed using two immunocytological techniques. A monoclonal antibody against BNIP-III (a marker of hypoxia) and TUNEL (Terminal deoxynucleotidyl Transferase Biotin-dUTP Nick End Labeling – an apoptotic detection process). An immunoflorescent counterstain DAPI (4′,6-diamidino-2-phenylindol) was used to stain all cells. Positive cells and total cell number were then counted in 10 high powered fields. The results showed a significant increase in BNIP-III expression in the cuff tears compared with intact tendons. This increase was least in the massive tears. Apoptosis increases from mild impingment to massive cuff tears (mean 7.3% to 21%) In conclusion, as tear size increases, the viability of the tendon reduces with increasing hypoxia and apoptosis.
The aim of this study was to determine cell viability in different stages of rotator cuff tendon tears using a cell viability molecular probe. Surgical biopsies taken from the edge of the Supraspinatus tendon tear from12 patients, 5 women and 7 men, mean age of 61 years were subjected to a cell viability assay using Molecular Probes Live/Dead cell viability assay. Specimens were then incubated with Calcein-AM and Ethidium Homodimer-1 and following snap freezing, sections were viewed under fluorescent microscopy. Cells which remained metabolically active fluoresced green, whereas dead cells were red. Populations of live and dead cells were counted for each specimen on ten high powered (x400 magnification) fields of view. The results show that the percentage of live cells is reduced in large chronic degenerate tears but greatest in acute traumatic tears. In addition, for those cases where tissue was assayed from the edge of the tear and 1 cm more proximally, there was a considerable increase in the percentage of viable cells in more proximal tissue. Use of this simple assay demonstrates high cell viability and consequently good quality tissue in traumatic tears, but lower quality tissue in larger more degenerate tears. This suggests that traumatic lesions have a high propensity to heal while larger more degenerate tears are less likely to heal but have better quality tissue more proximally.
The aim of this study was to observe the macroscopic and microscopic appearance of the Coracoacromial ligament and Subacromial bursa during Subacromial decompression and correlate it with the outcome at 3 months. Twenty patients with Subacromial Impingement without Rotator Cuff tear and five patients with large/massive irreparable Rotator Cuff tears who underwent a Subacromial Decompression. Patients with other shoulder pathology were excluded. Patients completed an Oxford Shoulder Score pre-operatively and their injection history was noted. At operation the shape of the acromion was noted. The macroscopic appearance of the CA ligament and the Subacromial bursa was classified as normal, mild/moderate and severe. Biopsies of the Subacromial bursa and CA ligament were taken and were analysed using histological and contempory immunocytochemical techniques. A histological analysis was performed using Mayer’s Haemotoxylin and Eosin, Toluidine Blue and Congo Red. Sections were stained with primary antibodies against PCNA (Proliferating cell nuclear antigen), Mast Cell Tryptase, CD3 (T-cell), CD20 (B cell), CD 34 (QBEnd 10), CD45 (Leucocyte Common Antigen), CD68 and D2–40 (Lymphatic Endothelial Marker). Post operatively the patients completed an Oxford Shoulder Score at 3 months. All the patients demonstrated an improvement in their Oxford Shoulder Score. The histological analysis demonstrated thickening of the synovial membrane and increased vascularity within the bursa and ligament. Increased numbers of inflammatory cells were present within the ligament and bursa of patients with impingement compared with massive rotator cuff tears. There was a relationship between outcome and the appearance of the bursa and ligament.
The aim of this study was to observe cellular and vascular changes in different stages of full thickness rotator cuff tear. Biopsies of the Supraspinatus tendon in 40 patients with chronic rotator cuff tears undergoing surgery were analysed using histological and contempary immunocytochemical techniques. Sections were stained with primary antibodies against PCNA (Proliferating cell nuclear antigen), CD34 (QBEnd 10), CD45 (Leucocyte Common Antigen), CD68, D2-40 (Lymphatic Endothelial Marker) and Mast Cell Tryptase. A histological analysis was performed with Mayer’s Haemotoxylin and Eosin, Congo Red and Toluidine Blue. The reparative response and inflammatory component (figure 1) of the tissue was seen to diminish as the rotator cuff tear size increased. This was evidenced by increasing degeneration and oedema, reducing fibroblast proliferation, reduced thickening of the synovial membrane and reducing vascularity. Macrophage, other leucocyte and mast cell numbers also reduced as tear size increased. Large and massive tears revealed a higher degree of chondroid metaplasia and amyloid deposition when compared to smaller sized tears. There was no association with the patient’s age or duration of symptoms. Small sized rotator cuff tears retain the greatest potential to heal and have a significant inflammatory component. Tissue from large and massive tears is of such a degenerate nature that it may never heal and this is probably a significant cause of re-rupture after surgical repair in this group. Selection of patients for reconstructive surgery should take into account the composition and healing potential of tendon tissue and its relationship to tear size in chronic tears of the rotator cuff.
The aim of this study was to use motion analysis to study a surgeon’s learning curve for an arthroscopic Bankart repair on a training model in a skills laboratory. Six fellowship trained lower limb surgeons unfamiliar with advanced shoulder arthroscopy performed an arthroscopic Bankart repair on an ALEX shoulder model. Standardised training was given and then an electromagnetic tracking system used to objectively assess hand movements, distance travelled by hands and time taken while the surgeons performed the technique. The arthroscopic repair was repeated three times on four consecutive occasions by each surgeon giving a total of 72 repair episodes. Analysis revealed improvement of all outcome parameters with less hand movements, less distance travelled and less time to complete the task. This study objectively demonstrates a learning curve for arthroscopic Bankart suture in a skills laboratory. It indicates the potential benefits of practicing aspects of arthroscopic techniques in a skills centre on appropriately selected models.
A prospective study was carried out to determine if recognised histological features seen at surgery could help predict those rotator cuff tendon repairs which re-ruptured. 40 rotator cuff tendon edge specimens from 40 patients’ shoulders were analysed histologically following routine mini-open rotator cuff repair. 32/40 underwent Ultrasonography, at a mean time of 35 months post-operatively, to determine repair integrity. The histological features seen at surgery were then compared to the repair integrity of the tendon from which it had been taken. Rotator cuff repairs that remained intact demonstrated a greater reparative response, in terms of increased fibrobast cellularity, cell proliferation and a thickened synovial membrane, than those repairs which reruptured. Larger tears which remained intact showed a higher degree of vasacularity and a significant inflammatory component than those that re-ruptured. Good tissue quality at the time of surgery allows the repair the best chance of remaining intact despite the size of the lesion. Routine histological analysis of the tissue biopsy, preformed in the post-operatively, can now aid the clinician in terms of early management and repair prognosis.
The aim of the study was to measure in-vivo the 10-year linear and volumetric polyethylene wear of a fully congruent mobile bearing unicompartmental knee arthroplasty (OUKA). We studied six OUKA’s that had all been implanted 10 years previously. Each patient was examined in even double leg stance at a range of knee flexion angles, in a calibration cage. A stereo pair of X-ray films was acquired for each patient at 0°, 15° and 30° of flexion. The films were analysed using an RSA style calibration and a CAD model silhouette-fitting technique. The position and orientation of each femoral and tibial component was found relative to each other and the bearing position inferred. Penetration of the femoral component into the original volume of the bearing was our estimate of linear wear. The volumetric wear is calculated from the measured linear wear and the known surface area of the bearing. In addition eight control patients were examined less than 3 weeks post-operation where no wear would be expected.and 30We studied seven OUKA’s that had all been implanted at least 10 years previously. A stereo pair of X-ray films was acquired for each patient at 0 Results: The control group showed no measured wear. The seven OUKA’s had an average maximum depth of linear penetration of 0.40 mm at a mean follow-up of 10.9 years. The linear wear rate was 0.033 mm/year. The volumetric material loss was 79.8 mm3. If a steady gradual material loss is assumed, 8 mm3 of UHMWPE was lost per year. Polyethylene particulate wear debris continues to be implicated in the aetiology of component loosening and implant failure knee following arthroplasty. The OUKA employs a spherical femoral component and a fully congruous meniscal bearing to increase contact area and theoretically reduce the potential for polyethylene wear. The results from this in-vivo study confirm that the device has low 10-year linear and volumetric wear in clinical practice. This may protect the device from component loosening in the long term.
When the Oxford unicompartmental meniscal bearing arthroplasty (UCA) is used in the lateral compartment of the knee 10% of the bearings dislocate. An in-vitro cadaveric study was performed to investigate if the anatomy and joint geometry of the lateral compartment was a contributory factor in bearing dislocation. More specifically, the study investigated if the soft tissue tension of the lateral compartment, as determined by the length of the lateral collateral ligament (LCL), was related to bearing dislocation. A change in length of greater than 2 mm is sufficient to allow the bearing to dislocate. The Vicon Motion Analysis System (Oxford Metrics, Oxford, UK) was used to assess length changes in the LCL of seven cadaveric knees. Measurements were made of the LCL length through knee flexion and of the change in LCL length when a varus force was applied at a fixed flexion angle. Measurements were made in the normal knee and with the knee implanted with the Oxford prosthesis. In the intact knee the mean LCL change was 5.5mm (8%) over the flexion range. After implantation with the Oxford UCA the mean change in length was only 1 mm (1%). There was a significant difference in the LCL length at 90° (p=0.03) and 135° (p=0.01) of knee flexion compared to the intact knee. When a varus force was applied the LCL length change of the intact knee (5.4 mm) was significantly different (p=0.02) to that of the knee with the prosthesis implanted (2.7 mm) This study used a new method to dynamically measure LCL length. It found that after implantation of the Oxford lateral UCA the LCL remains isometric over the flexion range and does not slacken in flexion as it in the normal knee. This would suggest that the soft tissue tension was adequate to contain the bearing within the joint. However, when a varus force was applied the LCL did not sufficiently resist a displacing force producing an LCL length change greater than 2 mm. The evidence provided by this study is contradictory. The “lack of change in LCL length through flexion” suggests that the ligament remains tight through range and is unlikely to allow dislocation. However, the amount of distraction possible when an adducting moment is applied is sufficient to allow bearing dislocation. The length tension properties of the lateral structures are therefore implicated in the mechanism of dislocation.
The indications for unicompartmental knee arthroplasty (UKA) can be contentious. Concerns exist about implanting a UKA in younger individuals. It has been reported that it is contra-indicated in patients under the age of 60. The suggestion is that younger patients may compromise their outcome after surgery by their increased activity levels. However, the number of publications with data on UKA in young patients is minimal and the age/activity related criteria for UKA remains unknown. The aim of the study was 1) to confirm that younger UKA patients have higher activity levels than older patients, and 2) to test the hypothesis that younger, more active patients have inferior outcome when compared to older less active patients. Fifty consecutive patients undergoing UKA who were under 60 years (Group Y) and 50 patients over 60 years (Group O) were recruited. Indications were anteromedial arthritis with full thickness lateral compartment cartilage, a functioning ACL and a correctible varus. All patients underwent Oxford UKA using the minimally invasive technique. This device employs an unconstrained fully congruous meniscal bearing. Outcome was evaluated using Knee Society Scores. Activity level was documented using Tegner Activity Score. Average age of patients for group Y and O was 55 and 68 years respectively. Minimum follw-up was 2 years. pre-op. knee scores were comparable for each group. (y: 38.8, O: 35.8) and patients in both groups siginificantly improved after surgery. A significant difference in Tegner score was found between the two groups after surgery (y:4.1, O:2.6). More than 50% of younger patients regularly participated in high demand activities like skiing, tennis and manual labour. No statistically significant differences in any other post op. knee scores or complication rate were found despite adequate study power. Younger patients have increased activity levels after UKA when compared to an older age group. There is no evidence that the outcome of UKA in younger more active patients will be inferior to those who are older and more sedentary.
