Introduction

The combined incidence of anatomic (aTSA) and reverse total shoulder arthroplasties (rTSA) in the US is 90,000 per annum and rising. There has been little attention given to potential long-term complications due to periprosthetic tissue reactions to implant debris. The shoulder has been felt to be relatively immune to these complications due to lower acting loads compared to other joint arthroplasties. In this study, retrieved aTSAs and rTSAs were examined to determine the extent of implant damage and to characterize the nature of the corresponding periprosthetic tissue responses.

Patients over 70 years old have subclinical or impending rotator cuff dysfunction, raising concern about TSA in this population. The purpose of this study is to examine whether reverse total shoulder arthroplasty (RTSA) should be considered for the treatment of glenohumeral osteoarthritis in the presence of an intact rotator cuff (GHOA+IRC in patients older than 70 years of age.

Twenty-five elderly (>70 years) patients at least one year status-post RTSA for GHOA+IRC were matched via age, sex, body mass index, smoking status, and whether the procedure involved the dominant extremity with 25 GHOA+IRC patients who received anatomic total shoulder arthroplasty (TSA). Standardised outcome measures, range of motion, and treatment costs were compared between the two groups. Treatment cost was assessed using implant and physical therapy costs as well as reimbursement.

Patients who received RTSA for GHO+IRC had significantly lower pre-operative active forward elevation (AFE, 69° vs. 98°, p <0.001) and experienced a greater change in AFE (p=0.01), but had equivalent AFE at final follow-up (140° vs. 142°, p=0.71). Outcomes were otherwise equivalent between groups with no differences. In both those patients who underwent TSA and those that underwent RTSA, significant improvements between pre-operative and final follow-up were seen in all standardised outcome measures and in AFE (p<0.001 in all cases). RTSA provided these outcomes at a cost savings of $2,025 in Medicare reimbursement due to decreased physical therapy costs.

In patients over the age of 70 with GHOA+IRC, RTSA provides similar improvement in clinical outcomes to TSA at a reduced cost while avoiding issues related to the potential for subclinical or impending rotator cuff dysfunction.

Introduction: Studies have shown Near Infrared Spectroscopy (NIRS) as being an effective tool in measuring oxygenation non-invasively in tissues. More recently it has been used in clinical settings to assess circulatory and metabolic abnormalities, however, clinical studies in bone are lacking.

Materials and Methods: Ten able-bodied (AB) (5 men and 5 women; age, 23-40 years) and ten spinal cord injured (SCI) (complete cord transection above T10, 5 men and 5 women; age 19–38) participants were matched by age, gender, skin pigmentation and studied.

A spectrometer measured between 498-1000nm, at 0.2Hz , using glass optodes (2mm diameter). Five minutes of resting readings, followed by 3 minutes of below knee arterial occlusion and then 6 minutes post-occlusion were made. The second study, started with 5 minutes of resting readings, vibration loading for 3 minutes at 30 Hz with acceleration of 3g and 6 minutes post-vibration was then conducted.

Results: NIRS showed changes in blood parameters during the hyperemic response (avg. 97% increase in Hb from baseline, p< 0.0001). Able-bodied subjects had significantly quicker (p=0.01) capacity for Hb to return to baseline. There was a significant difference (p=0.001) in the time to peak for Hb following arterial occlusion in the SCI group, 16.6 seconds (sd 4.3), and 10.1 seconds (sd 1.7) in the able bodied.

Conclusion: Our findings suggest that there is a reduction in the bone’s ability to restore oxygenated blood in SCI participants compared to the AB participants. Future studies looking at changes in bone following a range of vibration amplitudes and frequencies in the SCI group should be considered using NIRS in order to optimize potential clinical benefits.

Introduction: The clinical effectiveness of spinal bracing for the conservative treatment of adolescent idiopathic scoliosis is still not fully understood. Cohort studies on clinical effectiveness fail to adequately measure and control for confounding variables including spine flexibility, curve type, magnitude and maturity, distribution of corrective forces and compliance. This paper presents intermediate findings from a longitudinal study to objectively measure brace wear patterns and compliance in users of custom fitted TLSOs in the UK. Braces are fitted with data logging devices to measure temperature and humidity at the skin/brace interface. Previously reported measures of compliance have been in adolescents wearing Boston Braces using questionnaires, strap tension, interface pressure and skin temperature. They have shown compliance reported by the user can significantly over estimate actual compliance.

Methods and results: 20 patients are being studied over 18 months. TLSOs are fitted with data logging devices to measure temperature and humidity at the skin/brace interface. They are discrete sensors inserted into a pocket formed on the posterior of the brace. Measurements are recorded at 16 minute intervals and data downloaded every three to four months. Results clearly demonstrate compliance and daily wear routines. Temperature and humidity at the skin/brace interface during periods of wear are 35°C and > 80%RH respectively. Compliance ranges from 60–98%. Users who stick rigidly to their regime only remove their brace in the evening. Where poorer compliance is evident, the brace is worn sporadically during the day and evening, and worn full time at night.

Conclusion: Measurement of temperature and humidity at the skin/brace interface clearly demonstrates compliance and daily wear routines. Compliance varies from 60–98%. Where poor compliance is an issue it is intended to re-interview these individuals and obtain more detailed information about the reasons why they failed to use the brace.