Arthroplasties are widely performed to improve mobility and quality of life for symptomatic knee/hip osteoarthritis patients. With increasing rates of Total Joint Replacements in the United Kingdom, predicting length of stay is vital for hospitals to control costs, manage resources, and prevent postoperative complications. A longer Length of stay has been shown to negatively affect the quality of care, outcomes and patient satisfaction. Thus, predicting LOS enables us to make full use of medical resources.

Clinical characteristics were retrospectively collected from 1,303 patients who received TKA and THR. A total of 21 variables were included, to develop predictive models for LOS by multiple machine learning (ML) algorithms, including Random Forest Classifier (RFC), K-Nearest Neighbour (KNN), Extreme Gradient Boost (XgBoost), and Na¯ve Bayes (NB). These models were evaluated by the receiver operating characteristic (ROC) curve for predictive performance. A feature selection approach was used to identify optimal predictive factors. Based on the ROC of Training result, XgBoost algorithm was selected to be applied to the Test set.

The areas under the ROC curve (AUCs) of the 4 models ranged from 0.730 to 0.966, where higher AUC values generally indicate better predictive performance. All the ML-based models performed better than conventional statistical methods in ROC curves. The XgBoost algorithm with 21 variables was identified as the best predictive model. The feature selection indicated the top six predictors: Age, Operation Duration, Primary Procedure, BMI, creatinine and Month of Surgery.

By analysing clinical characteristics, it is feasible to develop ML-based models for the preoperative prediction of LOS for patients who received TKA and THR, and the XgBoost algorithm performed the best, in terms of accuracy of predictive performance. As this model was originally crafted at Ashford and St. Peters Hospital, we have naturally named it as THE ASHFORD OUTCOME.

Background:

The aim of this study was to review the surgical complications and clinical outcomes of patients with Pilon fractures treated with Ilizarov frames.

Shear plane non unions: biomechanical study and clinical application using an all wire Illizarov frame.

60 degree osteotomy of plastic tibiae were stabilised using four different Ilizarov frame configurations.

Models were loaded and shear displacement measured at the fracture site. The optimum frame design was identified and used in clinical practice.

The transfracture locked olive wire frame model offered the least displacement in the experimental model This frame model was used in two patients with shear plane non unions and both healed satisfactorily Both displacements had previously failed to unite with standard frame constructs.

Transfracture locked olive wire frame design is useful in the treatment of tibial non unions with shear plane.

Aim

Two different techniques to release subscapularis during total shoulder replacement (TSR) have been described (tenotomy and osteotomy) with no consensus as to which is superior. In this study we review the clinical outcomes of a sequential series of patients in whom a TSR for primary osteoarthritis had been performed using either technique at our institution. Subscapularis function was tested using a new graded belly press test, a modification of the traditional belly press test which is described for the first time here.

Background

The purpose of this retrospective study was to examine the functional outcomes of patients treated for isolated fracture of the greater tuberosity (GT) and to determine how their outcomes were affected by fracture pattern, treatment choices, associated shoulder injuries, the post fixation displacement of GT fragment and the time delay between injury and fixation.

Subscapularis function following Total shoulder joint replacement has been a concern in recent literature. It has been postulated that lesser tuberosity osteotomy approach may have better Subscapularis function than transtendonous approach.

To assess whether lesser tuberosity osteotomy vs. subscapularis tenotomy is better for post-operative function of subscapularis in total shoulder replacements done by a single surgeon in a District general hospital.

117 shoulder replacements performed by the senior author (TH) at Waikato district general hospital between years January 2002 to January 2010 were reviewed retrospectively. Revision replacement, inverse shoulder replacement & acute traumatic hemiarthroplasty were excluded. Patients with previous rotator cuff problems, previous surgery to subscapularis, rheumatoid arthritis and post-trauma sequelae were also excluded from the study. Inclusion criteria were normal subscapularis function and intact subscapularis on MRI pre-operatively.

41 shoulders were eligible to participate in study of which 1 pt died (bilateral TSR), 1 pt unfit to participate due to cervical disc problems. Of remaining 38 shoulders 11 shoulders had transtendonous and 27 shoulders had lesser tuberosity osteotomy approach. 37 shoulders were reviewed clinically for range of motion of the shoulder and subscapularis strength. Range of motion and subscapularis strength was significantly higher in the osteotomy group. All osteotomies were united on axillary radiograph.

Lesser tuberosity osteotomy approach result in better subscapularis function than transtendonous approach.

Isolated Greater Tuberosity (GT) fractures were described as separate entities from proximal humeral fractures more than 100 years ago. However, there is limited literature available about the functional outcome of the two different types of GT fractures: avulsed and comminuted

To compare functional outcomes of the 2 different types of Greater Tuberosity fractures; simple and comminuted and to determine how these outcomes were affected by associated injuries such as shoulder dislocation and rotator cuff tear. We also looked at the acceptable post fixation displacement of GT fracture and when to consider it mal-reduction (malunion due to over or under reduction) and the acceptable time frame to delay the fixation and still get satisfactory results.

We looked at Greater Tuberosity fractures of the humerus in Waikato Hospital between 1999–2009. Radiographs were reviewed by senior Author to classify them into simple and comminuted. Measurements were done by senior Author for post fixation displacement. Operative notes checked by the authors, when in doubt, double-checked by senior author. Outcome scores used: UCLA, ASES and oxford scores to compare functional outcome. We also measured the time off work and time on ACC (Physiotherapy), as well as period of follow up.

A total of 35 patients were included in the final analysis were treated operatively. Mean age of the patients was 51 years. M/F ratio was 3/2. Mechanism of injury was predominantly direct force applied to that shoulder. Shoulder dislocation was found in around 77% of patients. Methods of fixation included tension band wiring with or without screws, rotator cuff repair and one T-plate. Follow up time was shorter for simple comminuted fractures (22 v 44 weeks respectively). Outcome scores for patients who sustained simple fractures were slightly higher than those with comminuted fractures but the difference did not reach statistical significance. The groups with dislocation and rotator cuff tear did worse than the other groups in all aspects of the study. Post fixation displacement of GT of less than 5 mm led to a significantly better outcome than displacement of 5mm plus. Better results were obtained when the time between injury and operation was less than 2 weeks.

The comminuted group had similar functional outcome to the other group but required much longer follow up. Worse outcome should be expected with dislocation and rotator cuff tear associated with GT fracture. Satisfactory results relate to degree of displacement post fixation of <5 mm. Delay of fracture fixation of >2 weeks results in a less favourable outcome.

The results of a multi-surgeon, multi-implant series of patellofemoral joint arthroplasty performed over a ten year period are presented. All patellofemoral joint arthroplasty performed from the years 1996 to 2006 were retrospectively reviewed using case notes, radiographs and clinic appointments until their latest follow-up period.

101 arthroplasties in 91 patients were followed up for average period of 48 months (range 6–96 months). The average age was 57 years with female patients thrice as common as male patients. There were 5 (5%) complications with 1 deep infection and 4 stiff knees. 35 subsequent procedures were performed in 28 patients including arthroscopic debridement in 18, arthroscopic lateral retinacular release in 8, tibial tuberosity transfer in 3, manipulation for stiffness in 2, and revision to total knee arthroplasty in 4 patients (3 for progression of tib-iofemoral osteoarthritis and 1 for infection).

The necessity of further surgeries in one third of the study group suggests that close follow-up of these patients is needed to address any concerns that can be easily resolved.

Introduction: The aim of this study was to identify the pattern of symptoms in patients presenting with synovial sarcoma, examine how these corresponded to the symptoms outlined by the NICE guidelines on the rapid referral of patients with a suspected sarcoma and spot factors that led to long delays in diagnosis.

Methods: Early symptoms and the results of clinical and radiological investigation were reviewed along with the presumed diagnoses that had been made for 35 children. The total duration of symptoms was separated into patient delay and doctor delay.

Results: Using the four clinical findings suggestive of sarcoma according to the NICE guidance, only half of the patients had one or more of them at the time of initial symptoms. The most common presentation was a painless mass (n=16), and in 10 children there was no mass identified. Seven patients had an inexplicable joint contracture, many having been extensively investigated unsuccessfully. The mean duration of symptoms before the diagnosis was made was 98 weeks (range 2 to 364). The mean number of doctors seen prior to referral was 3 (range 1–6) and for 15 patients the diagnosis was obtained after inadvertent excision. The factors associated with long duration of symptoms before diagnosis were knee and elbow location (p=0.0047) or periarticular location (p=0.01), absence of lump (p=0.016) or painful mass as early symptom (p=0.04), the presence of calcifications on x-rays (p=0.01) and a fixed joint contracture (p=0.0003).

We could not show that delay in diagnosis led to a worse prognosis.

Discussion: This paper highlights the sometimes bizarre symptoms associated with synovial sarcoma and hopefully this will increase awareness of the condition among relevant sections of the medical profession and help to reduce the delay in diagnosing these cases.

Purpose: Isolated patellofemoral joint (PFJ) osteoarthritis has long been a common observation as an important source of knee pain. Once non-operative treatment modalities have been exhausted, the surgical options available are transposition/elevation of tibial tubercle, drilling, realignment procedures, patellectomy, patellar resurfacing, patellofemoral arthroplasty (PFA) and total knee arthroplasty (TKA). Among these, PFA is an established treatment of isolated PFJ osteoarthritis. We present our multi-surgeon, multi-implant series of patellofemoral joint arthroplasty performed over a 10 year period.

Method: This study was a retrospective review of all PFA performed in the Knee Arthroplasty Unit at our hospital over a ten year period from 1997 to 2006. The unit comprises seven specialist surgeons, each with considerable experience in knee arthroplasty and numerous trainee surgeons. One hundred and one PFA performed in 91 patients were identified from the theatre records. Three different implant models were used: the Lubinus implant (Waldemar Link), the FPV system (Wright Medical) and the Avon system (Stryker Howmedica Osteonics).

Results: 101 arthroplasties in 91 patients were followed up for average period of 48.8 months (6–96 months). Of these, none were lost to follow up. The average age was 57 years with female patients thrice as common as male patients. Concomitant procedures in the form of 23 lateral retinacular release or 6 osteochondral autograft transfer system (OATS) were performed. There were 6 complications with 2 infections and 4 stiff knees. 31 arthroplasties had subsequent procedures including arthroscopic debridement (18), arthroscopic lateral retinacular release (8), tibial tuberosity transfer (3) and manipulation for stiffness (2). A total of 4 arthroplasties underwent revision to total knee arthroplasty, 2 for infection and 2 for progression of tibiofemoral osteoarthritis.

Conclusion: The necessity of revision surgeries in one third of the cases suggests that close follow-up of the patients is needed to address any concerns that can be easily resolved. A majority of the patients in our study had very good outcomes and did not need subsequent procedures in the medium term. Our study reiterates the importance of proper patient selection, surgeon experience and correct surgical technique in successful outcomes from PFA.

Introduction: We have come across a subset of patients with advanced patellofemoral osteoarthritis who also had well defined full thickness cartilage loss lesions on the weight bearing femoral condyle. In these patients the findings or the symptoms are not severe enough to warrant a total knee replacement. In this select group of patients, a combination of patellofemoral arthroplasty (PFA) and Osteochondral Autograft Transfer System (OATS) can be performed to address this unique problem.

Method& Results: Out of 38 PFA procedures performed by the senior author, a concomitant OATS was performed in 6 knees in 5 patients. A retrospective analysis of these patients was carried out with the average follow up being 3.8 years (18 months to 84 months). The average age of the patients in our case study was 48.2 years (36 to 59 years) at the time of surgery. Four of the six knees are doing well in the medium term. One patient had progression of tibiofemoral arthritis and underwent a total knee replacement. The only poor result was a young male, who two years following the PFA, developed a deep infection of the knee. Except for this patient awaiting a second stage revision for an infected knee, all the others have achieved their desired level of activity.

Conclusion: The advantage of this combination is that, the donor tubes for the OATS can be harvested from the trochlea or just adjacent to it, which happens to be the bed for the trochlear implant. This area provides good quality thick donor articular cartilage. As the surgical exposure has already been done for the PFA, the operative time is extended by approximately ten minutes for the OATS procedure. This combination procedure offers an alternative to more invasive options such as total knee replacement in younger patients in whom it is preferable to delay such major surgery.

Introduction: Patellofemoral arthroplasty (PFA) is an established treatment of isolated patellofemoral osteoarthritis. We present our multi-surgeon, multi-implant series of patellofemoral joint arthroplasty performed over a ten year period.

Material & Results: his study was a retrospective review of all PFA performed in our unit over a ten year period from 1997 to 2006. The unit comprises seven specialist knee surgeons and numerous trainee surgeons. A total of 46 knees had the Lubinus implant (Waldemar Link), 30 knees had the FPV system (Wright Medical) and 25 knees had the Avon system (Stryker Howmedica).

101 arthroplasties in 91 patients were followed up for average period of 48.8 months (6–96 months). The average age was 57 years with female patients thrice as common as male patients. Concomitant procedures in the form of 23 lateral retinacular release or 6 osteochondral autograft transfer system (OATS) were performed. There were 6 complications with 2 infections and 4 stiff knees. Subsequent procedures included arthroscopic debridement (18), arthroscopic lateral retinacular release (8), tibial tuberosity transfer (3) and manipulation for stiffness (2). A total of 4 arthroplasties underwent revision to TKA, 2 for infection and 2 for progression of tibiofemoral osteoarthritis.

Conclusion: Thorough clinical history, physical examination and radiological investigation are essential before embarking on PFJ replacement. Other concomitant procedures like joint debridement, menisectomy or lateral retinacular release may be necessary to obtain optimum results. The necessity of revision surgeries in 31% of the cases of our study suggests that close follow-up of the patients is needed to address any concerns which can be easily resolved. PFJ replacement effectively addresses anterior knee pain, preserves the joint integrity, involves lesser surgical dissection and has good results of revision to TKA.

Background: As the understanding of bone repair mechanics has advanced the integrity of the bone pin interface has emerged as a key factor in determining the success of external fracture fixation. The benefits of using pins coated with Hydroxyapatite (HA) are well documented however the thickness of the conventional plasma spray coating precludes its use for modification of the surface of fine features in implants. Consequently new electro-chemical techniques for pre-coating implants with a ‘biomimetic’ HA layer using simulated body fluids (SBF) have been pioneered. In this study we test the hypothesis that varying the technique for deposition of HA by electrolysis of SBF alters the morphology of the HA surface which will modify the level of osseointegration. Method: Three alternative methods of HA coating the Barerre, Redepenning and Kumar techniques were compared. Tantalum coated stainless steel pins were coated then used to stabilise a mid-diaphyseal osteotomy in three sheep using an orthofix fixator for a period of ten weeks. Insertion and extraction torques were measured to calculate the pin performance index (PPI). Sections of the bones were then examined using scanning electron microscopy to determine the percentage of bone in contact with the pin surface and the percentage of new bone formation. Results: The different coating protocols resulted in different HA crystal morphologies. The extraction torque exceeded the insertion torque for both the Barerre and Redepenning methods and their PPI exceeds that of plasma spray coatings. The Redepenning technique was shown to perform sig-nificantly better than both the Barerre (p=0,001) and Kumar (p=0,001) techniques with 49.4% of the pin surface in contact with bone. These results were mirrored on analysis of new bone formation with the Redepen-ning technique showing 70.2% of new bone formation compared to the Barerre (55.4%) and Kumar (53.8%) methods. Conclusion: These results indicate that the Redepenning technique is the most effective for creating a bio mimetic HA coating in terms of bonding to bone and promoting new bone formation. This technique holds significant advantages over the conventional plasma spray technique for example the coating thickness can be easily controlled and additional proteins such as bone morphogenic proteins and antibiotics can be incorporated. It may therefore represent a new era in the use of HA coating.