Vertical pelvic ring displacement in pelvic ring injury: Measurements in pelvic outlet radiograph and in cadavers

Background:Vertical pelvic ring displacement (VPRD) is a serious injury and needs assessment. Pelvic outlet radiographs are routinely taken. However, relationship of radiographic and actual VPRD is still in question. Thus, measurement of VPRD from pelvic radiographs was studied.Results:Radiographic VPRD from outlet and anteroposterior pelvic views at 10 mm actual displacement were 20.12 ± 1.98 and 4.08 ± 3.76 mm, at 20 mm were 40.31 ± 1.97 and 9.94 ± 7.27 mm and at 30 mm were 58.56 ± 2.53 and 11.29 ± 2.89 mm. Statistical analyses showed that radiographic VPRD from pelvic outlet view is 1.95 times of actual displacement with strong correlation at 0.992 coefficient and strongly significant regression analysis (P < 0.001) with 0.984 of R² value. Whereas, the measurement from anteroposterior pelvic radiograph was not strongly significant.Conclusion:Pelvic outlet radiograph provides efficient measurement of VPRD with 2 times of actual displacement.     

Acetabular roof arc angles and anatomic biomechanical superior acetabular weight bearing area

Background:

Acetabular fracture involves whether superior articular weight bearing area and stability of the hip are assessed by acetabular roof arc angles comprising medial, anterior and posterior. Many previous studies, based on clinical, biomechanics and anatomic superior articular surface of acetabulum showed different degrees of the angles. Anatomic biomechanical superior acetabular weight bearing area (ABSAWBA) of the femoral head can be identified as radiographic subchondral bone density at superior acetabular dome. The fracture passes through ABSAWBA creating traumatic hip arthritis. Therefore, acetabular roof arc angles of ABSAWBA were studied in order to find out that the most appropriate degrees of recommended acetabular roof arc angles in the previous studies had no ABSAWBA involvement.

Materials and Methods:

ABSAWBA of femoral head was identified 68 acetabular fractures and 13 isolated pelvic fractures without unstable pelvic ring injury were enrolled. Acetabular roof arc angle was measured on anteroposterior, obturator and iliac oblique view radiographs of normal contralateral acetabulum using programmatic automation controller digital system and measurement tools.

Results:

Average medial, anterior and posterior acetabular roof arc angles of the ABSAWBA of 94 normal acetabulum were 39.09 (7.41), 42.49 (8.15) and 55.26 (10.08) degrees, respectively.

Conclusions:

Less than 39°, 42° and 55° of medial, anterior and posterior acetabular roof arc angles involve ABSAWBA of the femoral head. Application of the study results showed that 45°, 45° and 62° from the previous studies are the most appropriate medial, anterior and posterior acetabular roof arc angles without involvement of the ABSAWBA respectively.     

Lipid peroxidation,glutathione, vitamin E,and antioxidant enzymes in synovial fluid from patients with osteoarthritis

Aim: To compare levels of lipid peroxidation and antioxidants in synovial fluid from primary knee osteoarthritis (OA) patients with severe cartilage damage undergoing total knee replacement with those in the synovial fluid from injured knee joint patients with intact cartilage undergoing knee arthroscopy. Methods: Thirty‐two OA patients and 10 injured knee joint patients were recruited. Lipid peroxidation (thiobarbituric acid reactive substances [TBARs]), iron and glutathione (GSH) were measured using a colorimetric method. Vitamin E was measured with high‐performance liquid chromatography (HPLC). Activities of antioxidant enzymes (glutathione peroxidase [GPx], superoxide dismutase [SOD]) were analyzed with the use of a kinetic method. Results: TBARs, iron and GSH levels in synovial fluid were not significantly different between OA patients and injured knee joint patients. Antioxidant enzymes such as GPx and SOD activities also indicated no significant difference. Only vitamin E level was significantly lower in the synovial fluid of OA patients than in that of the injured knee joint patients. Conclusions: Oxidative stress may have a role in pathogenesis of knee osteoarthritis. Vitamin E supplementation may have a role in the management of patients.     

Measurement technique of calcaneal varus from axial view radiograph

Background:

Medial displaced posterior calcaneal tubercle creates varus deformity of an intraarticular calcaneal fracture. The fracture involves posterior calcaneal facet and the calcaneal body so we developed a measurement technique representing the angle between posterior facet and long axis of calcaneus using lateral malleolus and longitudinal bone trabeculae of posterior calcaneal tubercle as references to obtain calcaneal varus angle.

Materials and Methods:

52 axial view calcaneal radiographs of 26 volunteers were studied. Angles between posterior facet and long axis of calcaneus were measured using the measurements 1 and 2. Angle of measurement 1, as gold standard, was obtained from long axis and posterior facet of calcaneus whereas measurement 2 was obtained from a line, perpendicular to apex curve of lateral cortex of the lateral malleolus and a line parallel to the longitudinal bone trabeculae of posterior calcaneal tubercle. No more than 3° of difference in the angle of both measurements was accepted. Reliability of the measurement 2 was statistically tested.

Results:

Angles of measurement 1 and 2 were 90.04° ± 4.00° and 90.58° ± 3.78°. Mean of different degrees of both measurements was 0.54° ± 2.31° with 95% of confidence interval: 0.10°-1.88°. The statistical analysis of measurement 1 and 2 showed more than 0.75 of ICC and 0.826 of Pearson correlation coefficient.

Conclusion:

Technique of measurement 2 using lateral malleolus and longitudinal bone trabeculae of posterior calcaneal tubercle as references has strong reliability for representing the angle between long axis and posterior facet of calcaneus to achieve calcaneal varus angle.     

Posterior acetabular arc angle of unstable posterior hip fracture–dislocation

Purpose

Posterior hip fracture–dislocation needs stability evaluation. A previous study in the normal acetabulum has shown that the coronal posterior acetabular arc angle (PAAA) could be used to assess an unstable posterior hip fracture. Our study was designed to assess PAAA of unstable posterior hip fracture–dislocation and whether posterior acetabular wall fracture involves the superior acetabular dome.

Methods

Using coronal computed tomography (CT) of the acetabulum and 3D reconstruction of the lateral pelvis, we measured coronal, vertical PAAA and posterior acetabular wall depth of 21 unstable posterior hip fracture–dislocations and of 50 % normal contralateral acetabula. Posterior acetabular wall fracture was assessed to determine whether the fracture involved the superior acetabular dome and then defined as a high or low wall fracture using vertical PAAA in reference to the centroacetabulo–greater sciatic notch line.

Results

The coronal PAAA of unstable posterior hip fracture–dislocations and of 50 % of the posterior acetabular wall of normal the contralateral acetabulum were 54.48° (9.09°) and 57.43° (5.88°) and corresponded to 15.06 (4.39) and 15.61 (2.01) mm of the posterior acetabular wall without significant difference (p > 0.05). The vertical PAAA of unstable posterior hip fracture–dislocation was 101.67° (20.44°). There were 16 high posterior acetabular wall fractures with 35.00 (16.18) vertical PAAA involving the acetabular dome and 5 low wall fractures. High posterior wall fractures resulted in four avascular necroses of the femoral head, three sciatic nerve injuries and one osteoarthritic hip.

Conclusion

Coronal and vertical PAAA of unstable posterior hip fracture–dislocations were 54.48° and 101.67°. Vertical PAAA assesses high or low posterior acetabular wall fracture by referring to the centroacetabulo–greater sciatic notch line. High posterior wall fracture seems to be the most frequent and is involved with many complications.     

A comparison of survival rates for hip fracture patients with or without subsequent osteoporotic vertebral compression fractures

Little is known about the effect of a subsequent osteoporotic vertebral compression fracture on the survival rate of patients with a previous hip fracture. In this study, we aimed to compare the survival rates of hip fracture patients with and without subsequent osteoporotic vertebral compression fractures and determine the risk factors associated with subsequent fracture. During 2000-2008, 933 initial hip fracture patients were reviewed and divided into two groups: subsequent fracture group (160 patients) and single hip fracture group (i.e., no subsequent fracture; 773 patients). All information pertaining to their most recent fracture event(s), including mortality causes/rates, were recorded. Differences in mortality rates and hazard ratios (HRs) between the two groups were also analyzed. The 1-year and 1-to-5-year mortality rates were 1.3% and 1.9%, respectively, in the subsequent fracture group, and 4.7% and 1.4%, respectively, in the single hip fracture group, with no significant differences observed. Interestingly, the HR for mortality was significantly higher in the single hip fracture group than in the subsequent fracture group (p < 0.05). The significant risk factors for subsequent fractures were identified as knee osteoarthritis, neurological disease, and an initial hip fracture with intertrochanteric involvement. Our findings indicate that the occurrence of a vertebral compression fracture after an initial hip fracture does not greatly impact patient survival. Conversely, patients presenting with a single hip fracture have a significantly higher mortality-HR, indicating that single hip fracture patients without subsequent fracture should be provided with the same standard of care as patients with subsequent fractures.     

Roof-arc angle and weight-bearing area of the acetabulum

Background

Unreduced fracture crossing the weight-bearing dome of the acetabulum leads to arthritis. Thus the integrity of the weight-bearing dome is considered to be an important prognostic indicator for acetabular fracture. The decision of whether or not to operate is based on the location of the fracture relative to the weight-bearing dome. A displaced fracture crossing the weight-bearing dome is an indication for surgery.

Objective

To measure the medial, anterior, and posterior roof-arc angles that cross the weight-bearing dome.

Methods

Twenty cadeveric hip joints were dissected and simulated transverse fractures of acetabuli through the transtectal area were made. The radiographic examinations were taken in three views: AP, obturator oblique, and iliac oblique. Roof-arc angle was measured in all three views (medial, anterior, and posterior).

Results

The medial roof-arc angle was 46 ± 6.3°, anterior roof-arc angle was 52 ± 7.0°, and posterior roof-arc angle was 62° ± 8.5°.

Conclusions

In acetabular fracture, a medial roof-arc angle less than 46°, an anterior roof-arc angle less than 52°, or posterior roof-arc angle less than 61° is considered to be involved in a weight-bearing area.

Clinical relevance

These roof-arc angle values may be used as a surgical guideline for an acetabular fracture around the weight-bearing area.     

A retrospective analysis of medial opening wedge high tibial osteotomy for varus osteoarthritic knee

Background:

Medial opening wedge high tibial osteotomy (MOWHTO) has proven to be an effective treatment for varus osteoarthritic knees. Various methods of fixation with different implant types and using either bone grafts or bone substitutes have been reported. We performed non-locking T-buttress plate fixation with autologous iliac bone graft augmentation, which is defined here as the traditional method, and locking compression plate fixation without any bone graft or bone substitute. We aimed to compare bone union and complications of these two MOWHTO techniques.

Materials and Methods:

Between June 2005 and December 2007, 50 patients who underwent MOWHTO (a total of 60 knees) were retrospectively reviewed and classified into two groups: group A, which consisted of 26 patients (30 knees) was treated using T-buttress plate fixation with autologous iliac bone graft augmentation and group B, which consisted of 24 patients (30 knees) was operated upon using a medial high tibial locking compression plate without any augmentation. Demographic characteristics and radiographic outcomes, including union rate, time to union, medial osteotomy defects, and complications, were collected and compared between the two groups. The progress of all patients was followed for at least 2 years.

Results:

All osteotomies united within 12 weeks after surgery. Group B had slightly longer time to union than group A (10.3 weeks and 9.5 weeks, respectively; P = 0.125). A significantly higher incidence of medial defects after osteotomy was reported in the locking compression plate group (P = 0.001). A total of 5 (8.3%) knees had complications. In group A, one knee had a superficial wound infection and another knee had a lateral tibial plateau fracture without significant loss of correction. In group B, one knee had screw penetration into the knee joint and two knees had local irritation that required the removal of the hardware.

Conclusion:

Locking compression plate fixation without the use of bone grafts or bone substitutes provides a satisfactory union rate and an acceptable complication rate when compared to the traditional MOWHTO technique. Thus, we recommend using this technique for treating unicompartmental medial knee osteoarthritis.     

The genetic association between alpha-2-macroglobulin (A 2 M) gene deletion polymorphism and low serum A 2 M concentration in overweight/obese Thais

Abstract

The study subjects were 192 overweight and obese Thais (BMI > 25.00 kg/m 2 ), and 103 Thai controls (BMI = 18.50–24.99 kg/m 2 ), whose ages ranged from 18–60 years. All subjects were evaluated for serum Alpha-2-macroglobulin (A 2 M), globulin, albumin concentration, and polymorphic variation in the A 2 M gene. Serum A 2 M and albumin were significantly lower in the overweight/obese group ( P