Proximal hamstring tendon avulsion from the ischial tuberosity is a significant injury, with surgical repair shown to have superior functional outcomes compared to non-surgical treatment. However, limited data exists regarding the optimal rehabilitation regime following surgical repair. The aim of this study was to investigate patient outcomes following repair of proximal hamstring tendon avulsions between a conservative (CR) versus an accelerated rehabilitation (AR) regimen.

This prospective randomized controlled trial (RCT) randomised 50 patients undergoing proximal hamstring tendon repair to either a braced, partial weight-bearing rehabilitation regime (CR=25) or an accelerated, unbraced regime, that permitted full weight-bearing as tolerated (AR=25).

Patients were evaluated pre-operatively and at 3 and 6 months post-surgery, via patient-reported outcome measures (PROMs) including the Lower Extremity Functional Scale (LEFS), Perth Hamstring Assessment Tool (PHAT) and 12-item Short Form Health Survey (SF-12). Primary analysis was per protocol and based on linear mixed models.

Both groups were matched at baseline with respect to patient characteristics. All PROMs improved (p>0.05) and, while the AR group reported a significantly better Physical Component Score for the SF-12 at 3 months (p=0.022), there were no other group differences. Peak isometric hamstrings strength and peak isokinetic quadriceps and hamstrings torque symmetry were all comparable between groups (p>0.05). Three re-injuries have been observed (CR=2, AR=1).

After proximal hamstring repair surgery, post-operative outcomes following an accelerated rehabilitation regimen demonstrate comparable outcomes to a traditionally conservative rehabilitation pathway, albeit demonstrating better early physical health-related quality of life scores, without an increased incidence of early re-injury.

Avulsion of the proximal hamstring tendon from the ischial tuberosity is an uncommon but significant injury. Recent literature has highlighted that functional results are superior with surgical repair over non-surgical treatment. Limited data exists regarding the optimal rehabilitation regime in post-operative patients. The aim of this study was to investigate the early interim patient outcomes following repair of proximal hamstring tendon avulsions between a traditionally conservative versus an accelerated rehabilitation regimen.

In this prospective randomised controlled trial (RCT) 50 patients underwent proximal hamstring tendon avulsion repair, and were randomised to either a braced, partial weight-bearing (PWB) rehabilitation regime (CR = 25) or an accelerated, unbraced, immediate full weight-bearing (FWB) regime (AR group; n = 25). Patients were evaluated preoperatively and at 3 months after surgery, using the Lower Extremity Functional Scale (LEFS), Perth Hamstring Assessment Tool (PHAT), visual analog pain scale (VASP), Tegner score, and 12-item Short Survey Form (SF-12). Patients also filled in a diary questioning postoperative pain at rest from Day 2, until week 6 after surgery. Primary analysis was by per protocol and based on linear mixed models.

Both groups, with respect to patient and characteristics were matched at baseline. Over three months, five complications were reported (AR = 3, CR = 2). At 3 months post-surgery, significant improvements (p<0.001) were observed in both groups for all outcomes except the SF-12 MCS (P = 0.623) and the Tegner (P = 0.119). There were no significant between-group differences from baseline to 3 months for any outcomes, except for the SF-12 PCS, which showed significant effects favouring the AR regime (effect size [ES], 0.76; 95% CI, 1.2-13.2; P = .02).

Early outcomes in an accelerated rehabilitation regimen following surgical repair of proximal hamstring tendon avulsions, was comparable to a traditionally conservative rehabilitation pathway, and resulted in better physical health-related quality of life scores at 3 months post-surgery. Further long term follow up and functional assessment planned as part of this study.

Hamstring grafts have been associated with reduced strength, donor site pain and muscle strains following Anterior Cruciate Ligament Reconstruction (ACLR). Traditional graft fixation methods required both semitendinosus and gracilis tendons to achieve a graft of sufficient length and diameter, but newer techniques allow for shorter, broad single tendon grafts.

This study seeks to compare the outcomes between Single Tendon (ST) and Dual Tendon (DT) ACLR, given there is no prospective randomised controlled trial (RCT) in the literature comparing outcomes between these options.

In this ongoing RCT: (ANZ Clinical Trials Registry ACTRN126200000927921) patients were recruited and randomised into either ST or DT groups. All anaesthetic and surgical techniques were uniform aside from graft technique and tibial fixation. 13 patients were excluded at surgery as their ST graft did not achieve a minimum 8mm diameter. 70 patients (34 ST, 36DT) have been assessed at 6 months, using PROMS including IKDC2000, Lysholm and Modified Cincinnati Knee, visual analog scale for pain frequency (VAS-F) and severity (VAS-S), dedicated donor site morbidity score, KT-1000 assessment, and isokinetic strength.

Graft diameters were significantly lesser in the ST group compared to the DT group (8.44mm/9.11mm mean difference [MD],-0.67mm; P<0.001). There was a significant and moderate effect in lower donor site morbidity in the ST group compared to the DT group (effect size [ES], 0.649; P = .01). No differences between groups were observed for knee laxity in the ACLR limb (P=0.362) or any of the patient-reported outcome measures (P>0.05). Between-group differences were observed for hamstrings strength LSI favouring the ST group, though these were small-to-moderate and non-significant (ES, 0.351; P = .147).

ST (versus DT) harvest results in significantly less donor site morbidity and this is the first prospective RCT to determine this. There were no differences between ST and DT hamstring ACLR were observed in PROMs, knee laxity and hamstring strength. Younger female patients tend to have inadequate single tendon size to produce a graft of sufficient diameter, and alternative techniques should be considered. Further endpoints include radiological analysis, longer term donor site morbidity, revision rates and return to sport and will continue to be presented in the future.

Introduction

Clinical examination for stability in knee replacement involves the anterior drawer test. This test has been used to help in the diagnosis of flexion instability when used at 90 degrees and midflexion instability at 30 degrees. We sought to determine the inter-rater reliability of this test when compared to motion capture data.

INTRODUCTION

Utilization of a patient management support system in our clinical pathway has been successfully demonstrated to both reduce the length of hospital stay after primary THA, as well as reducing the number of hospital readmissions. While successful in a general patient population, the ability of a patient management support system to reduce readmissions in subsets of high risk THA patients has not been evaluated.

PURPOSE:

Medicare intermediary denial of primary joint replacements has become common over the past couple of years. Our community hospital had a marked increase in denials following the assignment of a new intermediary. Our purpose is to document the initial impact of these denials.

Periprosthetic joint infections (PJI) continue to be a diagnostic challenge for orthopedic surgeons. Chronic PJI are sometimes difficult to diagnose and occasionally present in a subclinical fashion with normal CRP/ESR and/or normal joint aspiration. Some institutions advocate for routine use of intraoperative culture swabs at the time of all revision surgeries to definitively rule out infection. The purpose of this study is to determine whether routine intraoperative cultures is an appropriate and cost effective method of diagnosing subclinical chronic PJI in revision joint replacement patients with a low clinical suspicion for infection.

We performed a retrospective chart review and identified 33 patients that underwent revision hip or knee replacement from a single surgeon over a five-month period. The AAOS guidelines for preoperative PJI workup were followed. 13 patients were diagnosed preoperatively with infection and excluded from the study. 20 patients underwent revision joint replacement and three separate cultures swabs were taken for each patient to help in determining true-positive cultures. Infectious Disease was consulted for all patients with any positive culture. Culture results were reviewed. At our hospital, the cost billed to insurance for a single culture is $1,458.58. We did not calculate the cost of the consultant fee.

Three (15%) of the 20 revision arthroplasty patients had a single positive culture. Infectious Disease consultants diagnosed all three of these positive cultures as contaminants. None of the patients had a true-positive intraoperative culture. The total cost billed by the hospital to obtain these cultures in all 20 patients was $87,514.80

In our study, obtaining a set of three intraoperative cultures for those patients with a negative preoperative infection workup was not only cost prohibitive but did not diagnose a single subclinical infection. Studies to find other more reliable, accurate, and cost effective alternatives to diagnose PJI are warranted.

In patients undergoing revision hip or knee arthroplasty with a low preoperative clinical suspicion for infection, it does not seem that routine intraoperative culture swabs are necessary or cost effective method for diagnosing subclinical periprosthetic joint infection.

Introduction and Aims: A method has been designed to accurately measure post-operative alignment of hip (acetabular) and knee (femoral and tibial) prosthetic components relative to the pre-operative plan. Conventional methods involve 2D measurements; this new method uses 2D-3D registration to align both the prosthesis and the pre-operative CT volume to the post-operative x-ray.

Method: The method uses an automatic approach to align a CAD model of the prosthesis to the post-operative x-ray. A rendering of the prosthesis is produced and overlaid onto the post-operative x-ray image. The prosthesis can be rotated and translated in 3D to match the outline of the rendering shown on the post-operative x-ray. An initial manual procedure is used to align the rendering of the bone surface from pre-operative CT to the bony anatomy on the post-operative x-ray. This manual registration position is then used as a starting position for an automated intensity-based registration algorithm.

Results: The automated intensity-based registration algorithm allowed 3D verification of the prosthesis position. A number of digitally reconstructed radiographs (DRRs) were produced by casting rays through the pre-operative CT volume. The DRRs were then compared with the post-operative X-ray image using a similarity measure. This similarity measurement was optimised using gradient decent-type search strategy to alter the rotation and translation parameters. If the Hounsfield numbers of the voxels, which the casting rays passed through, were integrated along the ray and projected onto an imaging plane, a radiograph-like image was produced. To concentrate the area of registration and thus quicken registration algorithm, the user also manually defined a region of registration interest. Hence, DRRs were only produced within the region of interest. Due to the large size of the pelvis and tube-like nature of the femur and tibia, a total of 10 starting positions were used for this algorithm. These starting positions were found by adding random Gaussian noise to the parameters found using the manual process. The registration position was defined as the final position that produced the best similarity measurement value.

Conclusion: Validation has demonstrated this method’s accuracy in calculating the post-operative position of acetabular and knee prostheses with respect to the pre-operative plan. The results are repeatable, robust and enable pre- and post-operative 3D implant position comparison. The inaccuracies observed with conventional methods due to incorrect alignment on x-ray are reduced.

Rheumatoid arthritis results in pain and loss of function due to gradual destruction of articular cartilage. The shoulder joint is frequently involved and a prosthetic replacement of the humeral head can restore function and relieve pain. Deficiency of the rotator cuff is common in patients with rheumatoid arthritis. Longevity of movement at the intraprosthetic interface of the bipolar shoulder prosthesis is debatable and has not previously been studied in rheumatoid arthritis.

We report a radiological study of the intraprosthetic movements of a bipolar shoulder replacement in 25 shoulders in 20 patients with rheumatoid arthritis of mean age 66 years (SD 10 years). Shoulders were X-rayed at a minimum of 3 and a maximum of 10 years from surgery. Measurements were repeated in 12 shoulders 3 years later. The patient was positioned in the scapular plane. An initial X-ray was taken with the arm in neutral and a further X-ray taken with the arm in full active abduction. Measurements were taken to determine the movement at the intraprosthetic interface and at the prosthesis/glenoid interface. Interobserver error and intraobserver error were determined using an intraclass correlation coefficient (ICC). A paired T-test and Pearson Correlation Coefficient were used to compare intraprosthetic movement with prosthesis/glenoid movement.

We found that intraprosthetic movement was preserved up to 10 years from surgery. However, there was no significant difference between intraprosthetic movement and shell/glenoid movement, with some shoulders exhibiting paradoxical movement at the intraprosthetic interface. Repeating the measurements after a 3 year interval in a subgroup of 12 shoulders showed a significant difference in intraprosthetic movement. Interobserver and intraobserver reliability for measurements of the movement at the intraprosthetic interface were excellent with a Kappa value of 0.92 for intraobserver error and a Kappa value of 0.94 for interobserver error.

We conclude that movement of the bipolar shoulder prosthesis in rheumatoid shoulders at the intraprosthetic interface is preserved up to 10 years from operation but is not related to or significantly different from prosthesis/glenoid movement and requires further investigation.