Radiographic Prediction of the Results of Long-term Treatment with the Pavlik Harness for Developmental Dislocation of the Hip

In 1957, Pavlik introduced the Pavlik harness as a useful treatment for developmental dislocation of the hip (DDH), and subsequent studies have documented favorable outcomes among patients treated with this device. However, there are only a few articles reporting how early radiographic measurements can be used to determine the prognosis after treatment with the Pavlik harness. In this study, 217 hips from 192 patients whose DDH treatment with the Pavlik harness was initiated before they were 6 months old and whose follow-up lasted at least 14 years (rate, 63.8%) were analyzed using measurements from radiographs taken immediately before and after harness treatment, and at 1, 2, and 3 years of age. Severin's classification at the final follow-up was I or II in 71.9% and III or IV in 28.1% of the hips, respectively. Avascular necrosis of the femoral head (AVN) was seen in 10% of the hips. Stepwise multiple regression analysis was performed to retrospectively determine whether any radiographic factors were related to the final classification as Severin I/II or III/IV. Receiver opera-ting characteristic (ROC) curves were drawn for these factors, and a Wiberg OE angle (Point O was the middle point of the proximal metaphyseal border of the femur) of 2 degrees on the 3-year radiographs was found to be the most useful screening value for judging the acetabular development of DDH cases after treatment with a Pavlik harness, with a sensitivity of 71% a specificity of 93%, and a likelihood ratio of 10.1.</p

Operative treatment for pincer type femoroacetabular impingement:a case report

Femoroacetabular impingement (FAI) is a condition characterized by the impingement of the femur and acetabulum. In Japan, this disorder has become recognized gradually. Here we report a rare case of surgically treated FAI, associated with an osseous protrusion on the acetabulum of a 30-year-old female. Plain computed tomography (CT) and reconstructive 3D-CT images clearly demonstrated an anterolateral bony protrusion. Hip arthroscopy showed no degeneration of the cartilage on either the femoral or acetabular side, but degeneration at the edge of labrum was observed in the region of the bony protrusion. The complete removal of the bony protrusion under hip arthroscopy was thus considered impracticable, and a small skin incision was therefore made anteriorly to approach the acetabulum. The Short-Form 36-Item Health Survey (SF-36) revealed improvement in all scores.</p

Possibility of Predicting Pelvic Inclination Following Total Hip Arthroplasty Based on the Preoperative State: Sacral Slope and Pelvic Incidence Minus Lumbar Lordosis as Predictive Factors

Following total hip arthroplasty (THA), some patients exhibit anterior or posterior pelvic tilt (PT). This case– control study investigated whether changes to PT following THA can be preoperatively predicted. Methods: 135 patients with hip osteoarthritis who underwent THA were assessed. The parameters measured preoperatively and one year postoperatively were lumbar lordosis (LL) based on plain X-ray and pelvic incidence (PI), PT, and sacral slope (SS), all of which were measured as pelvic morphological angles. Patients were classified into groups (A–E) based on the degree of post-THA PT, and their preoperative conditions were compared. PI minus LL was used to evaluate spinal alignment and pelvic balance. Results: Overall, 33%, 30%, 21%, 13%, and 3% of the hips of patients in Groups A, B, C, D, and E were postoperatively assessed. In Groups A–E, the SS values were 34.6°±8.9°, 37.6°±8.4°, 37.9°±8.9°, 42.6°±9.5°, and 60.0°±11.1°, whereas the PI minus LL values were 2.9°±15.0°, 1.2°±13.6°, 3.6°±17.7°, 12.7°±13.1°, and −1.3°±11.7°, respectively. Conclusions: Following THA, 70% of patients experienced posterior PT. Pre-THA SS ≥45° or PI minus LL ≥15° signified marked postoperative posterior tilt and could predict postoperative PT following THA. These findings are useful for implant placement, as they can predict pelvic inclination

Assessment of Head Wear More Than Ten Years after Total Hip Arthroplasty: 22-mm Zirconia VS. Metal Heads.

The present retrospective study assessed radiographs to determine socket wear in total hip arthroplasty (THA) with 22-mm zirconia or COP (Cobalt-Chrome alloy rich in Cobalt and Phosphorous) heads, and in cemented stems at more than 10 years after operation. Sockets of ultra high molecular weight polyethylene were used in each of two THA groups (13 hips each) in a clinical trial in our hospital between 1989 and 1990. Three observers carried out masked assessments of the radiographs. Upon fi nal examination, there was no remarkable loosening in the zirconia or COP group, and no case had required revision surgery as of 2005. There was a statistically signifi cant diff erence between the 2 groups in average annual linear wear, at 0.093 mm/year and 0.046 mm/year in the zirconia and COP groups, respectively. Volume wear and average annual volume wear were also signifi cantly greater in the zirconia group despite its superior mechanical strength and toughness in vitro. Our present fi ndings do not confi rm early expectations of lower wear in long-term results of 22-mm zirconia femoral heads used in THA

Radiological and clinical results of rotational acetabular osteotomy combined with femoral intertrochanteric osteotomy for avascular necrosis following treatment for developmental dysplasia of the hip

This retrospective study assessed the radiographic results of 16 patients with avascular necrosis following treatment for developmental dislocation of the hip (DDH) who were subsequently treated between 1991 and 2005 by rotation acetabular osteotomy (RAO) combined with femoral intertrochan-teric osteotomy (FIO). Initial treatment was by Pavlik harness, cast fixation, or overhead traction. The parameters that showed consistent improvement were the index of centralization, the index of acetabular coverage, adequate reduction of the greater trochanter, and abductor sufficiency. The combined procedure appears to be effective in cases in which preoperative planning shows a reasonable expectation of congruency and osteoarthritis is limited to the early stages.</p

Ten-Year Outcomes of Total Hip Arthroplasty Using Fit-and-Fill Type Cementless Collared Straight Stem Implants: Relationship between the Initial Contact Status and Stress Shielding

We investigated the relationship between the initial contact status and stress shielding in total hip arthroplasty (THA) using fit-and-fill type straight-stem implants. In addition we evaluated the clinical and radiographic outcomes. Subjects were 100 hips of 94 patients who underwent THA and were followed-up for ≥10 years. Contact areas with the femoral cortical bone were investigated according to the zonal distribution of Gruen using postoperative CT images. Depending on the number of contact areas, the patients were classified into high contact [HC], medium contact [MC], and low contact [LC] groups. Radiographic and clinical outcomes were evaluated. In the HC group (20 hips), severe stress shielding was observed in 12 hips, which was statistically significant (p=0.008). In the LC group (29 hips), mild stress shielding was observed in 27 hips which was statistically significant (p<0.001). No significant differences were observed among the 3 groups in clinical outcomes, Harris hip score (p=0.719) or Japanese Orthopedic Association (JOA) score (p=0.301). In insertion of cementless collared fit-and-fill type straight-stem implants, severe late stress shielding of the femoral bone may occur if high contact of the femoral component is achieved. However, the degree of stress shielding does not result in adverse clinical outcomes

Two-Directional Arthrographic Assessment for Treating Bilateral Development Dislocation of the Hips in Children after Walking Age

We reviewed the treatment outcome in 14 hips of 7 patients who were diagnosed as having bilateral developmental dislocation of the hip (DDH) after walking age and could be followed up until they were at least 14 years of age. Based on the results of two-directional arthrography of the hip, closed reduction was performed in 2 hips, and open reduction was performed without osteotomy in 12 hips. The final radiographic evaluations were made according to the Kalamchi and MacEwen classification and Severin classification. The mean age at the initial visit was 1 year and 9 months (range, 1 year and 5 months to 3 years). The outcome was satisfactory for one hip in Group Ⅰ and 2 hips in Group Ⅱ according to the Kalamchi and MacEwen classification, and in 83% of the Severin Class Ⅰ and Ⅱ hips. Arthrography was useful for identifying asymmetry, demonstrating the usefulness of a treatment strategy based on arthrography of the hip

Novel Technique for Removing a Well-Fixed Cemented Cup with a Dedicated Original Device during Revision Total Hip Arthroplasty: Surgical Technique

The improved cemented cup technique has attained excellent long-term results in primary total hip arthroplasty. When cup revision surgery was performed, the cemented cup, which was loosened at the bone-cement interface, was easily removed. However, with a well-fixed bone-cement interface, it remains difficult to remove the cemented cup for a revision in the event of a recurring dislocation. In addition, protrusions in the cement can cause unpredictable bone defects. A new removal device was created and used successfully to remove a well-fixed cemented cup safely and efficiently. This report introduces the device and the technique used in cemented cup removal