Introduction

Local commissioning groups are no longer funding outpatient follow up of joint replacements in an effort to save money. We present the costs of changing from traditional follow up methods to a virtual clinic at Warwick Hospital. Before September 2014 all joint replacements were seen in outpatients at six weeks, one year, five years, ten years and then every two years thereafter. They were usually reviewed, in a non-consultant led clinic, by a Band 7 specialist physiotherapist. This cost approximately £50 per patient including x-ray. Occasionally, the patients were seen in a consultant led clinic costing approximately £100.

Introduction

The standard plane imaging of Graf and the dynamic methods of Harcke are well established methods in assessing hip dysplasia but give limited information in the flexed-abducted treatment position used in the Pavlik harness. The femoral head may sit on the edge of the acetabulum in a flexed position and only reduce when the hips are abducted. This may mean that hips, which reduce when abducted in the Pavlik harness, appear subluxed when scanned in neutral abduction. Harness treatment may thereby be abandoned prematurely due to the failure to confirm reduction. This study identifies ultrasound landmarks on an anterior hip scan which could be used to confirm reduction of the hip in Pavlik Harness.

Objectives: Fresh osteochondral allografts are well-established treatment for patients who have posttraumatic osteochondral defects over 3cm in diameter and 1cm in depth of the knee. The objective of our study was to investigate the long-term outcome of these grafts and how long they may delay need for arthroplasty in patients with mal-united tibial plateau fractures.

Method: A prospective cohort study of patients who had received fresh osteochondral allografts of the tibial plateau was conducted. 118 patients were identified and survivor ship analysis was performed using conversion to total knee arthroplasty as the end point for graft failure. The Modified Hospital for Knee Surgery Scoring System (MHKSS) was used to clinically assess each patient who had more than five years of follow up. Radiographs were assessed for mechanical axis as well as using the Tonis grade for degenerative change.

Results: 29 of 118 (25%) experienced graft failure and underwent conversion to total knee arthroplasty, at a mean of 12 years (range 3–23) after the index procedure. The remaining 52 patients with a successful graft, and follow up over five years, had a mean MHKSS score of 83 (range 49–100) with a mean follow up of 11.7 years (range 5–34). Kaplan-Meier survivorship analysis of all 118 patients showed that graft survivorship was 94% at 5 years (std err 2.7), 83% at 10 years (std err 4.6), 62% at 15 years (std err 7.4) and 45% at 20 years (std err 8.5). Factors that predicted a successful graft were, using a meniscal allograft in conjunction with the osteochondral graft, and a lateral tibial plateau defect. The age at the time of surgery was no different between the patients that had a successful graft or those that failed.

Conclusion: Fresh osteochondral allografting works well in providing long term treatments for patients with tibial plateau damage. The concurrent use of meniscal allografts is also recommended.

When performing an intraarticular injection in the clinic setting the skin must first be cleaned with an antiseptic. This is typically done by spraying the skin with an alcohol based solution and allowing it to dry. Bony landmarks are then palpated to identify the correct insertion point for the needle. In the busy clinic setting this is sometimes done wearing sterile gloves, non-sterile gloves or no gloves at all. Potentially organisms from the palpating hand could contaminate the injection field and be introduced into the joint leading to a septic arthritis. We therefore looked at different scenarios often seen during intraarticular injections in clinic to see which was the least likely to contaminate the injection site.

In order to investigate the safest method of palpating bony landmarks whilst preventing infection we sprayed the entire volar surfaces, of both forearms, of fifty volunteers with alcohol. After the alcohol had dried, the subjects then palpated their own forearms in three separate areas with a naked digit, an unsterile-gloved digit and a digit itself sprayed with alcohol. Microbiology samples were taken using contact agar plates in each of the three areas as well as a control area, which had been sprayed but not touched. The number of bacterial colonies on the plates after incubation was then counted.

During transit to the incubator, three of the contact plate lids became dislodged. It could not be determined if further contamination had occurred and so all the samples from those volunteers were discarded. This left 188 contact plates (47 volunteers x 4 samples). The average number of colonies were, 14.5 for a naked digit, 3.5 for an unsterile glove, 2.0 for an alcohol sprayed digit and 1.7 for the control. Kolmogrov-Smirnov and Shapiro-Wilk tests were performed to assess the data for normality. The data was found to be highly skewed and therefore a Wilcoxon signed ranks test was performed comparing the three arms of the study with the control. There was a highly significant difference in the number of colonies between the naked digit and the control (p=0.0001) and to a lesser degree between the gloved digit and the control (p=0.030). No significant difference was found between the alcohol sprayed digit versus the control group (p=0.805).

In order to prevent contamination of an injection site after skin preparation the area should never be touched with a naked digit. We would also not recommend unsterile gloves often found in clinics. However, spraying your own fingers with antiseptic before palpating the injection site causes as much contamination as not touching it at all. This would seem to be a cheap and effective method as it avoids the cost of sterile gloves in clinic. We intend to extend the study further by adding an unsterile glove, which has been sprayed with alcohol. This may be the best solution of all.

The standard plane imaging of Graf and the dynamic methods of Harcke are well established methods in assessing hip dysplasia but give limited information in the flexed-abducted treatment position used in the Pavlik harness. The femoral head may sit on the edge of the acetabulum in a flexed position and only reduce when the hips are abducted. This may mean that hips, which reduce when abducted in the Pavlik harness, appear subluxed when scanned in neutral abduction. Harness treatment may thereby be abandoned prematurely due to the failure to confirm reduction. This study identifies ultrasound landmarks on an anterior hip scan which could be used to confirm reduction of the hip in Pavlik Harness.

Hips of a newborn piglet were scanned, imaged with magnetic resonance and x-rayed both before and after anatomical dissection. Radiographic markers delineated the position of the tri-radiate cartilage and potential ultrasound landmarks identified to help confirm hip reduction in the flexed-abducted position. Porcine imaging was then compared with that of a human newborn.

The porcine model corresponded well to human imaging and we were able to establish a landmark, the “Ischial Limb”, which corresponds to the ossification front delineating the posterior ischial edge of the tri-radiate cartilage. This could clearly be seen on anterior hip ultrasound of both the porcine and human hip. This landmark can be used to confirm the hip is reduced by reference to the centre of the femoral head.

We would recommend anterior hip scanning using the “Ischial Limb” as a reference point to confirm hip reduction in Pavlik harness. This simple method is a useful adjunct to conventional ultrasound scanning in the harness treatment of hip instability.

In order to prevent fatal pulmonary embolism TED stockings, foot pumps and early mobilisation on the second post-operative day are used at our centre. Only patients deemed to be high risk (previous DVT/PE or obese) are given Clexane as an inpatient and Warfarin for six weeks post op. 1137 primary hips and 1017 primary knees were identified using the hospital database and the figures confirmed with the theatre implant order books. Those patients now deceased on the database had their death certificates obtained from the coroner. No patients had died from pulmonary embolism within three months post operation. 34 patients had been discharged on Warfarin according to the pharmacy records. We would therefore not recommend the routine use of chemical thromboprophylaxis following joint replacement.