Assessment of approximate glenoid size in Thai people.

BACKGROUND: The loosening of the glenoid baseplate component is one of the most common complications after reverse total shoulder arthroplasty. The mismatch between size of baseplate and glenoid in Thai People may result in improper baseplate screw fixation and lead to early loosening of the glenoid component. Knowing of the glenoid size will guide the surgeon in placing or choosing the proper size glenoid baseplate to improve screw fixation strength. OBJECTIVE: Study the size ofglenoid in Thai people and compare with previous studies. MATERIAL AND METHOD: The authors measured the glenoid size in anteroposterior and superoinferior directions, the data were recorded in term of mean and standard deviation. The present data were then compared with the previous glenoid studies to identify the differences in size between Thai people and others. RESULTS: Among 160 patients with the mean age of 58.2 +/- 14.2 years, the overall glenoid sizefor the entire study group were 32.3 +/- 3.2 mm and 24.4 +/- 3.2 mm in superoinferior (SI) and anteroposterior (AP) directions, respectively. The male glenoid size were 35.6 +/- 2.6 mm and 26.7 +/- 2.5 mm in SI andAP directions, respectively. The female glenoid SI diameter were 31.0+1.9 mm and in AP diameter were 22.0 +/- 1.7 mm. The glenoid size in Thai people was significantly smaller than the glenoid size from previous studies in Caucasians. CONCLUSION: The overall glenoid size in Thai people was significantly smaller than the previous studies in Caucasians. The female glenoid was also smaller than with the male. These findings alert surgeons to choose the proper glenoid baseplate design to avoid an overhang problem and improve screw fixation, especially in Thaifemale patients.

Validity and reliability of the Thai functional internal rotation scale for shoulder arthroplasty.

Background: The Functional Internal Rotation Scale is an excellent clinical tool for evaluating patients with shoulder arthroplasty, but it has not been adapted to the Thai version. The objectives of this study were to translate the English version and culturally adapt the Functional Internal Rotation Scale to the Thai version and to examine the psychometric properties of the Thai Functional Internal Rotation Scale among Thai participants having shoulder arthroplasty. Methods: The Functional Internal Rotation Scale was translated to Thai, including cross-cultural adaptations, following standard guidelines. Psychometric properties were evaluated with shoulder arthroplasty patients. Content validity was evaluated using the content validity index (CVI). Criterion validity was assessed using the Pearson correlation coefficient. An Independent t-test was used to evaluate construct validity. Internal consistency reliability was assessed using Cronbach's alpha coefficient. Intraclass correlation coefficient (ICC) was used to determine test-retest reliability over a 14-day interval. Results: Of 45 participants, 20 total shoulder arthroplasty (TSA) patients and 25 reverse shoulder arthroplasty (RSA) patients, the majority of participants were female (69%) and retired (91%) with a mean age of 72.9 years (SD 9.1). CVI evaluation was acceptable, with a total CVI of 0.92. The correlation of the Thai Functional Internal Rotation Scale with the Thai version of the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (Thai ASES) and the internal rotation subscale (IR subscale) of the Thai ASES was 0.73 (P < 0.001) and 0.75 (P < 0.001), respectively. For construct validity, TSA patients scored, on average, 10.8 points higher than RSA patients (43.7 vs. 32.9, P < 0.001, 95% confidence interval 6.3-15.3). Cronbach's alpha coefficient of the Thai Functional Internal Rotation Scale was 0.95. The test-retest reliability revealed excellent reliability (ICC 0.99). Conclusion: The Thai Functional Internal Rotation Scale has good validity and excellent reliability in assessing internal rotation function in Thai shoulder arthroplasty patients.

Tibial footprint for single anatomical anterior cruciate ligament reconstruction by the meniscal reference point: the cadaveric study.

OBJECTIVE: ACL reconstruction is the gold standard for the torn ACL. To perform the anatomic reconstruction, knowledge of the footprint location is important. The femoral footprint was described in many studies, but the tibial footprint has less information. The authors study the relationship of ACL tibial footprint by using the meniscuses as landmark. MATERIAL AND METHOD: 20 knee specimens from the anatomy department were obtained and dissected. The footprint area was determined by locating the tibial stump of ACL first, isolated it from another structures, the footprint size was measured and then the mid portion of the footprint was identified. The relationship between the meniscuses to the mid portion of the ACL tibial footprint was determined. RESULTS: The authors have found that the mid portion of the A CL tibial footprint in all of specimens was located anterior to the posterior border of anterior horn of lateral meniscus, with the average of 3.2 +/- 0.25 millimeters. CONCLUSION: The meniscuses can be used as landmark to locate the footprint of the tibial part of the ACL. The mid portion of the ACL tibial footprint is anterior to the posterior border of anterior horn of lateral meniscus. This information will help the surgeons to locate the footprint with more accuracy while performing the anatomic ACL reconstruction.

The proximal humeral locking plate positioning to the pectoralis major tendon in achieving the proper calcar screw location: a cadaveric study.

BACKGROUND: Proximal humeral fracture is the third most common of osteoporotic fracture. Most surgical cases were treated by fixation with anatomical locking plate system. The calcar screw plays a role in medial support and improving varus stability. Proximal humerus fracture in elderly patients are commonly seen with greater tuberosity (GT) fracture. The GT fragment is sometimes difficult to use as an anatomic landmark for proper plate and screw position. Therefore, the insertion of pectoralis major tendon (PMT) may be used as an alternative landmark for appropriate plate and calcar screw position. The purpose of study is going to identify the vertical distance from PMT to a definite point on the position of locking plate. METHODS: 30 cadaveric shoulders at the department of clinical anatomy were performed. Shoulders with osteoarthritic change (n = 5) were excluded. Finally, 25 soft cadaveric shoulders were recruited in this study. The PHILOS™ plate was placed 2 mm posterior to the bicipital groove. A humeral head (HH) was cut in the coronal plane at the level of the anterior border of the PHILOS plate with a saw. A calcar screw was inserted close to the inferior cortex of HH. Distance from the upper border of elongated combi-hole (UB-ECH) to the upper border of pectoralis major tendon (UB-PMT) was measured. The plate was then moved superiorly until the calcar screw was 12 mm superior to the inferior border of HH and the distance was repeatedly measured. RESULTS: The range of distance from UB-PMT to the UB-ECH was from - 4.50 ± 7.95 mm to 6.62 ± 7.53 mm, when calcar screw was close to inferior border of HH and when the calcar screw was 12 mm superior to the inferior border of HH, respectively. The highest probability of calcar screw in proper location was 72% when UB-ECH was 3 mm above UB-PMT. DISCUSSION AND CONCLUSION: The GT fragment is sometimes difficult to use as an anatomic landmark for proper plate and screw position. PMT can be used as an alternative anatomic reference. UB-PMT can serve as a guide for proper calcar screw insertion. UB-ECH should be 3 mm above UB-PMT and three-fourths of cases achieved proper calcar screw location.