Surgical indications for treatment for femoroacetabular impingement with surgical hip dislocation.

Purpose: There is a lack of detailed information about the indications of surgical treatment for femoroacetabular impingement (FAI), particularly using open surgical dislocation. The purpose of this review was to systematically review the reported indications for surgical dislocation of the hip for FAI.

Methods: Two databases (MEDLINE and EMBASE) were screened for clinical studies involving the treatment for FAI with surgical hip dislocation.

Can the alpha angle assessment of cam impingement predict acetabular cartilage delamination?

Background: Substantial acetabular cartilage damage is commonly present in patients suffering from femoral acetabular impingement (FAI). A better understanding of which patient is at risk of developing substantial cartilage damage is critical for establishing appropriate treatment guidelines.

Questions/purposes: We asked: (1) Does the cam deformity severity in FAI as assessed by alpha angle predict acetabular cartilage delamination? And (2) what are the clinical and radiographic findings in patients with acetabular cartilage delamination?

Methods: One hundred sixty-seven patients (129 males, 38 females) with a mean age of 38 years (range, 17-59 years) underwent joint preservation surgery for cam-type FAI.

The effects of cam femoroacetabular impingement corrective surgery on lower-extremity gait biomechanics.

Surgery to correct cam femoroacetabular impingement (FAI) is increasingly popular. Nevertheless, no known study has analyzed both the three-dimensional lower-extremity joint kinematics and kinetics to quantify FAI surgical outcomes. The purpose of this study was to determine the effects of FAI surgery on the affected lower-extremity joint mechanics during gait by comparing the three-dimensional hip, knee, ankle and pelvic angular displacements, as well as the hip, knee and ankle moments and powers of preoperative and postoperative FAI groups, and a healthy control group.

Can T1-rho MRI detect acetabular cartilage degeneration in femoroacetabular impingement?: a pilot study.

Advanced MRI cartilage imaging such as T(1)-rho (T1ρ) for the diagnosis of early cartilage degradation prior to morpholgic radiological changes may provide prognostic information in the management of joint disease. This study aimed first to determine the normal T1ρ profile of cartilage within the hip, and secondly to identify any differences in T1ρ profile between the normal and symptomatic femoroacetabular impingement (FAI) hip. Ten patients with cam-type FAI (seven male and three female, mean age 35.

Comparison of total hip arthroplasty surgical approaches by Principal Component Analysis.

Gait adaptations are persistent after total hip arthroplasty and can depend on the type of surgery. This study focused on two surgical approaches: anterior and lateral. To analyze gait adaptations, biomechanical analyses usually employ an a priori selection of the parameters that leads to incomplete or redundant information.

Prevention of nerve injury after periacetabular osteotomy.

Background: The Bernese periacetabular osteotomy (PAO) is the preferred pelvic osteotomy in many centers treating symptomatic acetabular dysplasia in the young adult. Major nerve injury has been reported as a complication that can occur with this complex procedure, but the incidence and circumstances associated with such injury are not well known.

Questions/purposes: We asked: (1) What is the incidence of sciatic and femoral nerve injury after PAO; (2) what are the risk factors associated with such injury; and (3) what are the consequences of such injury including the degree of neurologic recovery?

Patients And Methods: We identified 1760 PAOs that were performed between 1991 and 2008 at five institutions.

Validity of a short-term quality of life questionnaire in patients undergoing joint replacement: the Quality of Recovery-40.

One hundred thirty-two patients undergoing total hip or knee arthroplasty were evaluated before and after surgery with the Quality of Recovery-40 (QoR-40) and the Short Form 12 (SF-12) questionnaires seven times over a 4-month period, with the objective of comparing their psychometric properties. Physical dimensions of the QoR-40 and SF-12 were not related in the days after surgery but moderately related over the first month. Only the change in score for the physical independence dimension of the QoR-40 exceeded measurement error.

Lower-limb joint mechanics after total hip arthroplasty during sitting and standing tasks.

While the effect of total hip arthroplasty on the operated limb mechanics is well documented, little is known on its effect on the contralateral limb. The purpose of this study was to measure the joint mechanics of both lower limbs during the tasks of sit-to-stand and stand-to-sit. Twenty total hip arthroplasty patients and 20 control participants performed three trials of each task from which 3D lower-limb joint kinematics and kinetics were obtained.

New frontiers in cartilage imaging of the hip.

High-resolution MRI for cartilage mapping is a rapidly evolving field that is contributing to a better understanding of osteoarthritis. The basic science of cartilage imaging uses different modalities (such as T1rho, T2 mapping, delayed gadolinium-enhanced MRI of cartilage) and has clinical applicability for treating hip disorders in the young adult. These imaging techniques rely on biomarkers to quantify early cartilage degeneration.

High incidence of migration with poor initial fixation of the Accolade stem.

Background: Numerous cementless femoral stem design variations are in clinical use. Because initial implant instability and micromotion are associated with aseptic loosening of the femoral component, migration analysis provides an early assessment of implant survivorship.

Questions/purposes: We determined the (1) migration pattern of the Accolade cementless femoral stem; (2) clinical factors predisposing to stem migration; (3) self-reported patient outcomes; and (4) our current rate of aseptic stem loosening.

Multicenter study of complications following surgical dislocation of the hip.

Background: Surgical hip dislocation enables complete exposure of the hip joint for treatment of various hip disorders.There is limited information regarding the complications associated with this procedure. Our purpose is to report the incidence of complications associated with surgical dislocation of the hip in a large, multicenter patient cohort.

Cobalt and chromium levels in blood and urine following hip resurfacing arthroplasty with the Conserve Plus implant.

Background: The purpose of the present study was to determine cobalt and chromium ion levels in the blood and urine of patients in whom a modern-generation metal-on-metal hip resurfacing device had been implanted.

Methods: A total of ninety-seven patients with a Conserve Plus metal-on-metal hip resurfacing implant were followed prospectively for two years. Cobalt and chromium levels in erythrocytes, serum, and urine were measured preoperatively as well as three, six, twelve, and twenty-four months postoperatively.

Computer-assisted correction of cam-type femoroacetabular impingement: a Sawbones study.

Background: Assessing the adequacy of bone resection when correcting cam-type femoroacetabular impingement can be difficult when the surgeon is inexperienced or when less-invasive arthroscopic surgical techniques are used. The primary purpose of the present study was to compare, using a Sawbones model, the results of computer-assisted navigated osteochondroplasty of the femoral neck junction with correction with use of femoral head spherometer gauges. The second objective was to compare the results of computer-assisted osteochondroplasty performed by surgeons who had varied experience with the procedure.

Incidence of deep vein thrombosis and pulmonary embolus following periacetabular osteotomy.

Background: Venous thromboembolism, a known complication of orthopaedic procedures, is thought to be more prevalent following hip surgery. Venous thromboembolism risk assessment and appropriate prophylaxis according to the American College of Chest Physicians guidelines has become the standard of care. However, it is accepted that venous thromboembolism prophylaxis is associated with potential adverse sequelae including hematoma, wound drainage, and infection.

Preoperative and postoperative lower-extremity joint and pelvic kinematics during maximal squatting of patients with cam femoro-acetabular impingement.

Background: Understanding how the function of the lower extremity joints during everyday movements following surgery to treat cam femoro-acetabular impingement is essential to assess whether surgical intervention effectively restores the normal biomechanics of the hip. The purpose of this study was to compare preoperative and postoperative lower-extremity joint and pelvic angular displacements during maximal depth squatting of patients with unilateral symptomatic cam femoro-acetabular impingement.

Methods: Ten participants were compared with respect to their preoperative and postoperative test results.

The Shenton line in the diagnosis of acetabular dysplasia in the skeletally mature patient.

Background: Undetected developmental dysplasia of the hip can progress to hip instability, which can lead to the development of early osteoarthritis. The purpose of the present study was to determine the reliability and accuracy of the Shenton line in the diagnosis of acetabular dysplasia in the skeletally mature patient.

Methods: Supine anteroposterior pelvic radiographs were obtained for a total of 128 hips in patients with a diagnosis of developmental dysplasia of the hip prior to pelvic osteotomy (sixty-four hips, including thirty-two left and thirty-two right hips) and normal patients (sixty-four hips, including thirty-two left and thirty-two right hips).

Does the anterior approach for total hip arthroplasty better restore stair climbing gait mechanics?

While total hip arthroplasty (THA) provides pain relief and restores mobility, gait anomalies persist even years after surgery. A muscle sparing surgical approach could result in better postoperative gait mechanics. Our purpose was to compare both the anterior muscle sparing approach and the direct lateral approach (LAT) to a matched control group by using three-dimensional motion analysis while performing stair ascent and descent tasks.

A prospective metal ion study of large-head metal-on-metal bearing: a matched-pair analysis of hip resurfacing versus total hip replacement.

The current study measured ion release among large-head metal-on-metal hip bearings. Twenty-six patients with a modular, Profemur® TL with A-Class® big femoral head total hip replacement were matched (gender, femoral size, BMI) with a group of 26 patients with the Conserve® Plus implant hip resurfacing. Compared with HR patients, THR patients had higher median serum cobalt ion levels at 6 months (3.

In vitro assessment of strength, fatigue durability, and disassembly of Ti6Al4V and CoCrMo necks in modular total hip replacements.

Modularity in total hip replacement offers advantages with regard to biomechanical adjustments and leg lengths. Recently, modular femoral necks were introduced as an added advantage to head modularity permitting further adjustments in femoral version as well as offset and ease of revision. Currently, most necks are made of Ti6Al4V for which cases of in vivo fractures and inseparable neck-stem junctions have been reported.

Prevalence of cam-type femoroacetabular impingement morphology in asymptomatic volunteers.

Background: Femoroacetabular impingement is a cause of hip pain in adults and is a possible precursor of osteoarthritis, with the cam type of impingement being the most common. The purpose of this study was to determine the prevalence of cam-type morphology of the hip in asymptomatic patients.

Methods: Two hundred asymptomatic volunteers with no prior hip surgery or childhood hip problems underwent magnetic resonance imaging targeted to both hips.

Validity of the alpha angle measurement on plain radiographs in the evaluation of cam-type femoroacetabular impingement.

Background: Cam-type femoroacetabular impingement is secondary to lack of concavity at the anterosuperior femoral head-neck junction, resulting in reduced femoral head-neck offset and femoral head asphericity. This morphologic deformity can be detected by MRI and plain radiographs and quantified using the alpha angle.

Questions/purposes: We evaluated the accuracy and reproducibility of plain radiography in the diagnosis of cam-type deformity.

Comparison of joint mechanics of both lower limbs of THA patients with healthy participants during stair ascent and descent.

Total hip arthroplasty (THA) is a common surgical procedure for patients suffering from osteoarthritis to relieve their pain and to attempt to restore their normal locomotion patterns. Although this procedure does not restore normal mobility during activities of daily living, it remains unclear how it affects the joint mechanics of both lower limbs during stair negotiation tasks. Hence, we compared the 3D joint mechanics of both lower limbs of THA patients with matched healthy controls during stair ascent and stair descent.