A Novel Method to Measure Superior Migration of the Humeral Head: Step-off of the C-line

BACKGROUND: Superior migration of humeral head has been conventionally determined by measuring the acromiohumeral distance (AHD), We sought to devise a novel measurement system more reliably and accurately than AHD. We described a structural landmark called 'C-line'. In this study, we investigated the clinical usefulness of 'step-off of the C-line (SOC)' compared to that of AHD. METHODS: The C-line formed from the medial margin of the proximal humeral head continuing up to the inferior margin of the articular glenoid and then to the lateral border of the scapula. The superior migration of the humeral head triggered by a rotator cuff tear introduces a discontinuity in this C-line. We measured the distance of this discontinuity. We enrolled 144 patients who underwent a rotator cuff repair. We selected 58 controls who didn't have any cuff lesions apparent on magnetic resonance imaging. Using radiographs derived from standardized true anteroposterior views of the shoulder, we measured the SOC and the AHD. We used t-tests for statistical analyses. RESULTS: A rotator cuff tear was associated with an increase in SOC and a decrease in AHD. In control group, the mean SOC was 1.29 ± 1.71 mm and AHD was 9.71 ± 2.65 mm. In cuff tear group, the mean SOC was 3.15 ± 3.41 mm and AHD was 8.28 ± 1.76 mm. The mean SOCs of the patient group in relation to the mean SOC of the control group according to tear size, the SOCs of medium tear and lager groups showed statistically significant increase (p<0.05). CONCLUSIONS: The SOC may be a similarly effective to diagnose cuff tears of medium size and larger compared with AHD.

Biomechanical Test for Repair Technique of Full-thickness Rotator Cuff Tear

The arthroscopic rotator cuff repair is now considered a mainstream technique with highly satisfactory clinical results. However, concerns remain regarding healing failures for large and massive tears and high revision rate. In recent decades, various repair strategies and construct configurations have been developed for rotator cuff repair with the understanding that many factors contribute to the structural integrity of the repaired construct. The focus of biomechanical test in arthroscopic repair has been on increasing fixation strength and restoration of the footprint contact characteristics to provide early rehabilitation and improve healing. These include repaired rotator cuff tendon-footprint motion, increased tendon-footprint contact area and pressure, and tissue quality of tendon and bone. Recent studies have shown that a transosseous tunnel technique provides improved contact area and pressure between rotator cuff tendon and insertion footprint, and the technique of using double rows of suture anchors to recreate the native footprint attachment has been recently described. The transosseous equivalent suture bridge technique has the highest contact pressure and fixation force. In this review, the biomechanical tests about repair techniques of rotator cuff tear will be reviewed and discussed.

Is the Incidence Rate of Hip Fractures still Increasing in Korea?: An Epidemiologic Study Based on National Health Insurance Database / 대한정형외과학회잡지

PURPOSE: A retrospective study was conducted to examine the current trend in incidence rates of hip fractures among patients aged 50 years and older in Korea. MATERIALS AND METHODS: A retrospective study was conducted using data on the population, collected by Statistics Korea within the different gender and age groups in total population of Korea from 2007 to 2012. The International Classification of Diseases-10 classification method from the Health Insurance Review and Assessment Service was used to investigate the number of patients with hip fractures, and determine the crude incidence rate (CR) and the age-adjusted incidence rate (AR) for comparison. RESULTS: The CR of hip fractures for patients aged 50 years and older was 178 per 100,000 for men and 350 per 100,000 for women in 2007. In 2012, the CR was 194 per 100,000 for men, and 418 per 100,000 for women. The AR was 197 per 100,000 for men and 281 per 100,000 for women in 2007. In 2012, the AR was 206 per 100,000 for men, and 310 per 100,000 for women. During the observation period, the AR and the CR of hip fractures showed a statistically significant increase. However, the increasing trend has been slowing since its peak in 2010. Comparison of the AR of men and women, showed statistical significance only for women. CONCLUSION: In Korea, the incidence of hip fractures increased significantly from 2007 to 2012. The AR showed statistical significance only for women and the increasing trend is slowing down from 2010.

A Novel Method to Measure Superior Migration of the Humeral Head: Step-off of the C-line

BACKGROUND: Superior migration of humeral head has been conventionally determined by measuring the acromiohumeral distance (AHD), We sought to devise a novel measurement system more reliably and accurately than AHD. We described a structural landmark called 'C-line'. In this study, we investigated the clinical usefulness of 'step-off of the C-line (SOC)' compared to that of AHD. METHODS: The C-line formed from the medial margin of the proximal humeral head continuing up to the inferior margin of the articular glenoid and then to the lateral border of the scapula. The superior migration of the humeral head triggered by a rotator cuff tear introduces a discontinuity in this C-line. We measured the distance of this discontinuity. We enrolled 144 patients who underwent a rotator cuff repair. We selected 58 controls who didn't have any cuff lesions apparent on magnetic resonance imaging. Using radiographs derived from standardized true anteroposterior views of the shoulder, we measured the SOC and the AHD. We used t-tests for statistical analyses. RESULTS: A rotator cuff tear was associated with an increase in SOC and a decrease in AHD. In control group, the mean SOC was 1.29 ± 1.71 mm and AHD was 9.71 ± 2.65 mm. In cuff tear group, the mean SOC was 3.15 ± 3.41 mm and AHD was 8.28 ± 1.76 mm. The mean SOCs of the patient group in relation to the mean SOC of the control group according to tear size, the SOCs of medium tear and lager groups showed statistically significant increase (p<0.05). CONCLUSIONS: The SOC may be a similarly effective to diagnose cuff tears of medium size and larger compared with AHD.

Biomechanical Test for Repair Technique of Full-thickness Rotator Cuff Tear

The arthroscopic rotator cuff repair is now considered a mainstream technique with highly satisfactory clinical results. However, concerns remain regarding healing failures for large and massive tears and high revision rate. In recent decades, various repair strategies and construct configurations have been developed for rotator cuff repair with the understanding that many factors contribute to the structural integrity of the repaired construct. The focus of biomechanical test in arthroscopic repair has been on increasing fixation strength and restoration of the footprint contact characteristics to provide early rehabilitation and improve healing. These include repaired rotator cuff tendon-footprint motion, increased tendon-footprint contact area and pressure, and tissue quality of tendon and bone. Recent studies have shown that a transosseous tunnel technique provides improved contact area and pressure between rotator cuff tendon and insertion footprint, and the technique of using double rows of suture anchors to recreate the native footprint attachment has been recently described. The transosseous equivalent suture bridge technique has the highest contact pressure and fixation force. In this review, the biomechanical tests about repair techniques of rotator cuff tear will be reviewed and discussed.