Association between Sacral Slanting and Adjacent Structures in Patients with Adolescent Idiopathic Scoliosis

BACKGROUND: Sacral slanting is a frequent unique phenomenon in patients with adolescent idiopathic scoliosis (AIS) and may be important for selecting the distal fusion level. However, the reason of the phenomenon remains unknown. The purpose of this study was to determine the association between sacral slanting and adjacent structures in patients with AIS. METHODS: A total of 303 AIS patients who underwent both whole spine standing anteroposterior (AP) and whole leg standing AP radiography were included. The degree of sacral slanting, pelvic obliquity, lumbar curve angles (L1-L4), and L4 tilt were assessed on whole spine standing AP radiographs. Whole leg standing AP radiographs were used to assess the degree of leg length discrepancy (LLD). Demographic data and radiological parameters were analyzed descriptively. Pearson correlation analysis and partial correlation analysis of the parameters were performed. A p-value of less than 0.05 was considered statistically significant. RESULTS: The proportion of patients with ≥ 5° of sacral slanting among those with < 3° of pelvic obliquity was 8.9% (27/303). Thirty-two patients (10.6%, 32/303) showed more than 10 mm of LLD. Sacral slanting was positively correlated with pelvic obliquity and lumbar curve (r = 0.445 and r = 0.325, respectively). Pelvic obliquity was also correlated with LLD and L4 tilt (r = 0.123 and r = 0.311, respectively). However, partial correlation analysis showed that LLD was not directly correlated with sacral slanting (r = −0.034). CONCLUSIONS: Sacral slanting can be thought to be a compensatory mechanism for large lumbar curves, which is accompanied by pelvic obliquity. In contrast, a congenitally slanted upper sacrum may contribute to scoliosis in some cases. LLD was not directly correlated with sacral slanting.

Basic Pelvic Parameters Associated with Lumbar Degenerative Disease: Review Article

STUDY DESIGN: Literature review. OBJECTIVES: The aim of this study was to present updated information on the basic pelvic parameters associated with lumbar degenerative disease. SUMMARY OF LITERATURE REVIEW: Sagittal imbalance has been known to be related to a poor prognosis in almost all adult spine problems, including lumbar degenerative disease. MATERIALS AND METHODS: Review of the relevant literature. RESULTS: Pelvic incidence is a morphologic parameter of the pelvis. It influences lumbar lordosis and thoracic kyphosis, and determines the limitations of pelvic retroversion in sagittal imbalance. Pelvic tilt is a positional parameter of the pelvis, indicating the degree of compensation for sagittal imbalance. A C7-sagittal vertical axis >5 cm, pelvic tilt >20°, and pelvic incidence-lumbar lordosis mismatch are known to be independent factors predictive of poor outcomes. CONCLUSIONS: The C7-sagittal vertical axis, pelvic tilt, and pelvic incidence-lumbar lordosis mismatch should be considered when surgery is planned for a patient with degenerative lumbar disease.

Early Aseptic Loosening after Total Knee Replacement Using Legacy Posterior Stabilized-Flex Prosthesis / 대한정형외과학회잡지

PURPOSE: We analyzed the patterns and causative factors of early aseptic loosening after total knee arthroplasty (TKR) using a legacy posterior stabilized (LPS)-flex prosthesis. MATERIALS AND METHODS: We examined 483 cases that occurred in 311 patients who underwent TKR using LPS-flex by single surgeon between August 2001 and March 2007 and who were followed-up for at least 2 years. The loosened group included 25 cases that exhibited early aseptic loosening on radiograph, the remaining 458 cases were regarded as the control group, and analysis was performed. RESULTS: The mean loosening period was 34.7 months and femoral component loosening alone was found in 22 cases (88%). There were no statistically significant differences in age, body mass index, or pre-operative range of motion between the 2 groups, but varus deformity was more severe in the loosened group (mean 8.92degrees) than in the control group (mean 5.21degrees) (p=0.003). Protrusion of the femoral component proximally over posterior condyle of the distal femur were more prominent in the loosened group (mean 20.3%) than in the control group (mean 13.4%) (p=0.001). CONCLUSION: Early loosening after TKR using LPS-flex prosthesis developed mostly in the femoral component. Choosing a proper size for the femoral component and cutting level for the distal femur should be considered.

The Length of the Patellar Tendon in Normal Adults

PURPOSE: This study was conducted to measure the length of the patellar tendon in normal adults and to analyze the effect of several anthropological variables on the patellar tendon length. MATERIALS AND METHODS: The study included 316 knees (278 males, 38 females) that were undergoing anterior cruciate ligament reconstruction with a bone-patellar-bone autograft. The patellar tendon length was measured on the middle 1/3 of the ipsilateral patellar tendon taken during the operation and we analyzed the relationships between the tendon length and age, weight, height and gender using simple correlation tests and linear regression analysis. RESULTS: The mean tendon length was 42.6 mm (range: 30~60 mm) and the mean age, mean weight and mean height was 32.7 years, 72.8 kg and 170.2 cm, respectively. There was weak negative correlation between the tendon length and age (Pearson correlation r=-0.187) and weak positive correlation between the tendon length and weight (r=0.288) but there was no significant correlation between tendon length and the body mass index (p=0.282) There was a positive correlation between tendon length and height (r=0.434). There was a significant difference between the males and females for the length of tendon (p<0.001), yet after removing the variance of height, the difference was statistically insignificant (beta=-0.041, p=0.491). The linear regression equation for the patellar tendon length (y, in centimeters) as a function of height (x, in centimeter) can be expressed as y=0.032x1.183. CONCLUSION: The length of the patellar tendon is correlated with height, and a patient's height can predict the length of the patellar tendon.

Factors Affecting the Range of Motion after Revision Total Knee Arthroplasty

PURPOSE: We aimed to analyze the clinical results and investigate the factors that affect the range of motion (ROM) after revision total knee arthroplasty. MATERIALS AND METHODS: We measured the range of motion from 61 knees of 55 patients who underwent revision total knee arthroplasty using the Nexgen(R) LCCK and we investigated the factors affecting the postoperative ROM, including age, the body mass index (BMI), the preoperative ROM, deformity, causes of revision (septic vs. aseptic) and the type of polyethylene inserts (constrained vs. posterior-stabilized). The clinical results and radiographic findings were assessed using the American Knee Society Score and the roentgenographic method of the American Knee Society. RESULTS: The mean range of motion was improved from 113.7degrees to 127.2degrees. The preoperative ROM (p=0.000) and diagnosis (p=0.006) significantly influenced the postoperative ROM, yet age (p=0.386), BMI (p=0.054), deformity (p=0.218) and the type of polyethylene insert (p=0.195) were not related to the postoperative knee ROM. The American Knee Society Knee Score and Function Score on average was improved from 31.7 and 27.9 points to 86.7 and 64.7 points, respectively. CONCLUSION: The range of motion and clinical results were satisfactory after revision total knee arthroplasty using the Nexgen(R) LCCK, and the important factors affecting the range of motion after operation were the preoperative ROM and the causes of revision. The range of motion after arthroplasty using the constrained type polyethylene insert was not inferior to that using the posterior-stabilized insert.

Bony Ankylosis Secondary to Heterotopic Ossification Following Total Knee Arthroplasty: A Case Report

Bony ankylosis secondary to heterotopic ossification following total knee arthroplasty is extremely rare, and to the best of our knowledge, there has been no reported case of this in Korea. We present such a case in a 48 year-old female who underwent primary total knee replacement due to traumatic osteoarthritis.

Treatment of the Acromioclavicular Joint Dislocation Using a AO Hook Plate

PURPOSE: We wanted to evaluate the results of treating acromioclavicular joint dislocation using an AO hook plate. MATERIALS AND METHODS: Between February 2008 and September 2009, 10 patients underwent implant removal after surgical treatment of acromioclavicular joint dislocation using a AO hook plate. The Constant-Murley scoring system was administered postoperatively for evaluating the clinical results, and simple X-ray was taken for evaluating the state of reduction. RESULTS: All cases showed satisfactory results on the clinical and radiological study. The mean Constant-Murley score at follow-up was 90.5 (range: 84~95). Three patients had some degree of discomfort with the hook plate, but these symptoms were relieved on removal of the plate. The radiological evaluation showed restoration of the vertical displacement of the clavicle in all the patients. No complications occurred such as infection, plate failure or redislocation after removal of the plate. CONCLUSION: The short term follow-up results of treating acromioclvicular joint dislocation using an AO hook plate were satisfactory both clinically and radiologically.