Novel method of measuring patellar height ratio using a distal femoral reference point

Purpose  

Patellar height is an important factor in patellar tracking and alters the force of the patellofemoral joint reaction. Several methods for measuring patellar height ratio have been described, with no single method recognised as a gold standard. This study developed a new measurement method using a distal femoral reference, where the normal values of measurement are unaffected by varying angles of knee flexion.     

Revision Hip Arthroplasty Using a Modular,Cementless Femoral Stem: Intermediate-Term Follow-Up

Background

Modular femoral stem provides flexibility in femoral reconstruction, ensuring improved “fit and fill”. However, there are risks of junction failure and corrosion, as well as cost concerns in the use of modular femoral stems.

Elevated Body Mass Index Is Associated With Early Total Knee Revision for Infection

Background

Obesity affects over half a billion people worldwide, including one-third of men and women in the United States. Obesity is associated with higher postoperative complication rates after total knee arthroplasty (TKA). It remains unknown whether obese patients progress to revision TKA faster than nonobese patients.

Increased cerebral blood flow on arterial spin labeling magnetic resonance imaging can localize to seizure focus in newborns: A report of 3 cases

Arterial spin labeling (ASL) magnetic resonance imaging (MRI) can assess cerebral blood flow (CBF) without using radiolabeled tracers. It is unknown whether regional increases in CBF on ASL MRI correlate with seizure location in newborns. We report 3 newborns with focal seizures localized on continuous video electroencephalogram (cEEG), anatomical brain MRI, and ASL MRI. Each patient underwent pseudocontinuous ASL with segmented 3‐dimensional fast spin echo readout as part of standard care. Case 1 is a term male infant presenting with left temporal status epilepticus and recurrent cEEG seizures from an idiopathic large left intraventricular hemorrhage. ASL images demonstrated left mesial temporal lobe increased CBF. Case 2 is a late preterm male infant presenting with recurrent cEEG seizures due to focal right megalencephaly. Ictal EEG and ASL images coincided with the focal dysplasia. Case 3 is a dysmorphic term female infant with nonconvulsive partial status epilepticus identified by focal increased CBF of the left temporal lobe on ASL images. The area of increased CBF was within an area of extensive left hemisphere dysplasia. To our knowledge, this is the first report of regional increases in CBF on ASL MRI correlating with ictal cEEG in newborns.     

Medial proximal tibial angle after medial opening wedge HTO: A retrospective diagnostic test study

Background:

Medial proximal tibial angle (MPTA) is the commonly used angle, which is simply measured from the knee radiographs. It can determine the correction angle in medial opening wedge high tibial osteotomy (MOWHTO). The hypothesis of our study is that post-osteotomy MPTA can predict the change in correction angle, and we aimed to determine the optimal MPTA with which to prevent recurrent varus deformity after MOWHTO.

Materials and Methods:

Between January 2002 and April 2010, radiographs of 59 patients, who underwent 71 MOWHTOs using the locking-compression osteotomy plates without bone grafts, were evaluated for the change of the MPTA. The MPTA was measured preoperatively and one and twelve months postoperatively. The changes of MPTA between one and twelve months were classified into valgus, stable, and varus change. The predicting factors were analyzed using analysis of variance (ANOVA) and Bonferroni multiple comparisons. The receiver operating characteristic (ROC) curve was used to find out the cut off point for preventing the recurrent varus deformity.

Results:

The overall preoperative, and one and twelve month postoperative MPTA values were 84.4 ± 2.4°, 97.2 ± 4.1°, and 96.3 ± 3.6°, respectively. Between one and twelve months, 39 knees displayed reduced varus change (–2.8 ± 2.1°), 18 knees displayed no change, and 14 knees displayed a greater valgus change (+2.9 ± 2.1°). The best factor for predicting these changes was the one month MPTA value (P = 0.006). By using the ROC curve, a one month MPTA of 95° was analyzed as the cut off point for preventing the recurrent varus deformity. With MPTA ≥95°, 92.3% of the osteotomies exhibited stable or varus change and 7.7% exhibited valgus change. However, with MPTA <95°, 47.4% exhibited stable or varus change and 52.6% exhibited valgus change (P < 0.001, odds ratio = 13.3).

Conclusion:

The postoperative MPTA can be used to predict the change in correction angle and an MPTA of at least 95° is the crucial angle with which to prevent recurrent varus deformity.     

Three-hour interval drain clamping reduces postoperative bleeding in total knee arthroplasty: a prospective randomized controlled trial

Background

Total knee arthroplasty (TKA) is a common procedure that has a risk of significant blood loss and blood transfusion, and carries a substantial risk for immunologic reactions and disease transmission. Drain clamping is a popular method that is applied to reduce blood loss after TKA. However, the clamping protocol remains controversial. Therefore, we established a new protocol, 3-h interval clamping, and compared the bleeding control efficacy of this protocol following TKA with the non-clamping technique.

Methods

Between March and July 2008, we enrolled 100 patients (100 knees) who underwent uncomplicated TKA using a minimally invasive surgical technique. The patients were randomly assigned into two groups based on the draining protocol: non-clamping (group A) and 3-h interval clamping (group B). For group A, a vacuum drain was connected to a container and was run continuously during the first postoperative day, whereas the vacuum was stopped twice (for ~3 h each time) for group B. Demographic characteristics and clinical data were collected, including the levels of hemoglobin and hematocrit, the total blood loss volume, the number of patients who required a blood transfusion, and any complications that developed. The perioperative data were compared between the two groups.

Results

The drainage blood volume in the interval-clamping group (group B) was significantly lower than that in the non-clamping group (group A) during the first 48 h following the procedure (p < 0.001 and p = 0.005 for first and second postoperative days, respectively). The mean fall in hemoglobin levels at 12 h in the interval-clamping group (2.8 ± 0.9 g/dL) was also lower than in the non-clamping group (3.2 ± 0.8 g/dL). In the 3-h interval clamping protocol, the number of patients requiring a transfusion was 2.2 times less than the number in the non-clamping protocol, but was not significantly different (odds ratio = 2.20, p = 0.24), and the significant predictor of blood transfusion was the preoperative hemoglobin level (odds ratio = 7.73, p < 0.001). No wound infection or clinical venous thromboembolisms were detected in our study.

Conclusion

The 3-h interval clamping is a newly developed protocol for reducing blood loss after TKA. The protocol lessens the decrease in postoperative hemoglobin levels. This protocol can be applied easily without increasing clinical thromboembolic events and wound complications.     

Outcome of 4 Surgical Treatments for Wear and Osteolysis of Cementless Acetabular Components

Background

Loosening and periprosthetic osteolysis are some of the most common long-term complications after hip arthroplasty. The decision-making process and surgical treatment options are controversial.