Aim

The aim of this study is to identify the incidence of the presence of an Inverted Radial Reflex (IRR) in asymptomatic subjects with Adolescent Idiopathic Scoliosis and determine its significance.

Purpose

This study aims to identify factors that influence the Cobb angle at presentation to a tertiary referral scoliosis centre, and the outcome of the referrals.

Introduction: The JRI Furlong HAC LOL hemiarthroplasty stem has shown increased periprosthetic fracture rates compared to previous literature (15.2% vs 7.4%) [1,2,3]. This study seeks to identify a measurable radiographic index, the Metaphyseal-Diaphyseal Index (MDI) score to determine whether intra-operative fracture in osteoporotic bone can be predicted to influence the type of prosthesis used (cemented or uncemented).

Methodology: A 5 year prospective cohort of 560 consecutive patients underwent hemiarthroplasty (cemented or uncemented). A nested case-control study to determine risk factors affecting intra-operative fracture was carried out.

Clinical outcomes and radiographic analysis was performed. The Vancouver Classification was used to classify periprosthetic fracture.

The MDI score was calculated using radiographs, as a control (gold standard), Yeung’s CBR score was calculated [4]. See Figure 1. A receiver operating characteristic (ROC) curve was formulated for both and area under the curve (AUC) compared. Intra and inter-observer correlations were determined.

Cost analysis was also worked out.

Results: 407 uncemented and 153 cemented stems were implanted. The use of uncemented implants was the main risk factor for intra-operative periprosthetic fracture.

62 periprosthetic fractures occurred in the uncemented group (15.2%), 9 in the cemented group (5.9%), p< 0.001. The revision rate for sustaining a periprosthetic fracture (uncemented group) was 17.7%, p< 0.001 and 90 day mortality 19.7%, p< 0.03.

MDI’s AUC was 0.985 compared to CBR’s 0.948, p< 0.001. See Figure 2. The MDI score cut-off to predict fracture was 21, sensitivity 98.3%, specificity 99.8%, PPV 90.5%, NPV 98%. ANCOVA ruled out any other confounding factors as being significant.

The intra and inter-observer Pearson correlation scores were r=0.99, p< 0.001.

The total extra cost due to the intra-operative fractures was £93,780.

Discussion: The MDI score is a useful, cost effective way of preventing this serious complication from occurring. We recommend that any femur scoring 21 or less on the MDI score be considered for cemented hemiarthroplasty.

Level of evidence: Level 2 Diagnostic Study: Development of diagnostic criteria on basis of consecutive patients (with universally applied reference “gold” standard).

Distal femoral LCP was used in 41 consecutive distal AO type A and type C fractures; Vancouver C periprosthetic femoral shaft fractures and Lewis and Rorabeck Type 2 periprosthetic supracondylar fractures of the femur between Oct 2005 and Feb 2008 at a District General Hospital in UK. We aim to present the functional and radiological results at a mean duration of 18.7 months after the surgery.

Between Oct 2005 and Feb 2008, forty patients with a total of forty-one fractures were treated with a distal femoral LCP. There were seventeen male patients and twenty three female patients with a mean age of 73.8 years. There were 29 distal femoral fractures (AO type A = 20; type C = 9) and 12 periprosthetic fractures (Vancouver C = 4; Lewis and Rorabeck Type 2 = 8). Six of the fractures were open. Clinical and radiographic results, including union time, malalignment and implant complications were assessed. Function was assessed by using the Knee Society score. The mean duration of follow-up was 18.7 months (range, seven to thirty five months).

Thirty seven fractures united during this follow up. Three fractures which showed features of delayed or non union needed additional procedures. Screw loosening necessitating screw removal was required in three patients. Deep infection was seen in one patient. Malalignment more than 10 degrees in AP or Lat views was evident in five cases. Excellent to good Knee Society score was achieved in 82 percent of cases. Fair to poor score was seen in 18 percent of cases.

Distal femoral locking plates offer more fixation versatility without an apparent increase in mechanical complications or loss of reduction.

Introduction: The JRI Furlong HAC LOL hemiarthroplasty stem has shown increased periprosthetic fracture rates compared to previous literature(15.2% vs 7.4%). This study will seek to identify a measurable radiographic index, the Metaphyseal-Diaphyseal Index (MDI) score to determine whether intra-operative fracture in osteoporotic bone can be predicted to influence the type of prosthesis used (cemented or uncemented).

Methodology: Over 5 years prospectively, a cohort of 560 consecutive patients undergoing hemiarthroplasty (cemented and uncemented) were evaluated. Clinical outcomes and radiographic analysis was performed. The Vancouver Classification was used to classify peri-prosthetic fracture. The MDI score was calculated using radiographs from the uncemented group. As a control (gold standard), Yeung et al’s CBR score was also calculated. From this, a receiver operating characteristic (ROC) curve was formulated for both scores and area under the curve (AUC) compared. Intra and inter-observer correlations were determined. Cost analysis was also worked out for adverse outcomes.

Results: 407 uncemented and 153 cemented stems were implanted. 62 periprosthetic fractures occurred in the uncemented group (15.2%), 9 occurred in the cemented group (5.9%), p< 0.001. The revision rate for sustaining a periprosthetic fracture (uncemented group) was 17.7%, p< 0.001. MDI’s AUC was 0.985 compared to CBR’s 0.948, p< 0.001. The MDI score cut-off to predict fracture was 21, sensitivity 98.3%, specificity 99.8%, positive predictive value 90.5% and negative predictive value 98%. ANCOVA analysis ruled out any other confounding factors as being significant. The intra and inter-observer Pearson correlation scores were r=0.99, p< 0.001. The total extra cost due to the intra-operative fractures was ú40,140.

Discussion: The MDI score has been shown to be a potentially useful, cost effective way of preventing this serious complication from occurring. We recommend that any femur scoring 21 or less on the MDI score be considered for cemented hemiarthroplasty. Level of evidence: Level 2 Diagnostic Study: Investigating a diagnostic test against gold standard.