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Bernard R Bach

Publications and source records attributed to Bernard R Bach.

36 records · Page 2Linked to original sources
PubMed2004

Posterior cruciate ligament reconstruction: current trends.

A survey was conducted of the Herodicus Society membership to assess the current status of treating posterior cruciate ligament (PCL) injuries and compared to a similar survey conducted in 1991. The survey addressed indications, graft choice, surgical technique, graft tensioning, and graft fixation. Seventy-eight active surgeons were sent a 34-question survey pertaining to isolated PCL injuries. The majority of respondents (78%) performed < or = 10 PCL reconstructions per year. The arthroscopic assisted with posteromedial portal technique was the most commonly used (49%). The tibial inlay/onlay technique was used by 15%, and 68% used the single femoral tunnel technique. The remainder used a double femoral tunnel technique. Allograft Achilles tendon was the most commonly selected graft for acute (43%) and chronic (50%) PCL reconstructions. An interference screw for femoral fixation was used 67% of the time. The majority of respondents (55%) tensioned their single bundle or anterolateral band of a double bundle in 71 degrees-90 degrees of flexion. A significant difference in technique was noted when comparing those who performed < or = 10 PCL reconstructions per year (group 1) versus > 10 PCL reconstructions per year (group 2). In group 1, 25% of surgeons used a double tunnel technique versus 59% of surgeons in group 2. The most common operative treatment for PCL injuries consisted of a single femoral tunnel with an Achilles tendon allograft. When compared to a similar survey conducted in 1991, the notable differences were a trend toward Achilles tendon allograft and the popularization of the double femoral tunnel and tibial inlay/onlay technique.

Achilles Tendon↗
PubMed2004

Shoulder scoring scales for the evaluation of rotator cuff repair.

Various assessment tools have been proposed for evaluation of shoulder function. Analyses of comparability, validity, and reliability among shoulder assessment tools are lacking. The purpose of our investigation was to compare the results of three commonly used shoulder assessment tools in the evaluation of a specific shoulder condition. Seventy-two full-thickness rotator cuff tears were treated with an open rotator cuff repair from 1986-1993. The average age of the patients at surgery was 58 years (range, 24-92 years). The median duration of followup at the time of evaluation for this study was 55 months (range, 24-102 months; standard deviation, 22 months). Correlation among the results of the UCLA, Constant-Murley, and the Simple Shoulder Test scales was fair (range, 0.66-0.76). More importantly, the three systems were evaluated for their ability to accurately predict improved motion, strength, and patient satisfaction. The Simple Shoulder Test and the Constant-Murley scales showed the highest positive predictive values. The Simple Shoulder Test is a patient-based self-assessment device that easily can be incorporated into a busy clinical practice, providing outcome data comparable with complex evaluation systems when evaluating the results of rotator cuff repair.

Adult↗
PubMed2004

Contact pressure at osteochondral donor sites in the patellofemoral joint.

BACKGROUND: The lowest contact pressure point is presumed to be the best site to harvest an osteochondral plug and minimize morbidity. HYPOTHESIS: Patellofemoral contact pressures are not uniform and are lowest along the medial patellofemoral articulation. STUDY DESIGN: Controlled laboratory study. METHODS: Seven cadaveric knees were tested with an electroresistive, dynamic pressure sensor placed onto the femoral side of the patellofemoral joint. The extensor mechanism was loaded with 89.1 N and 178.2 N, and the knee was manually cycled 3 times (0 degrees -105 degrees ) per load. Mean trochlear pressures were calculated. RESULTS: Mean contact pressures were greatest in the central trochlea (5.80 kgf/cm(2)), followed by the lateral (2.56 kgf/cm(2)) and medial trochlea (1.60 kgf/cm(2)) at 89.1 N (P <.05). At 178.2 N, pressures increased to 9.47, 5.81, and 2.75 kgf/cm(2), respectively (P <.05). Lateral trochlear pressures decreased moving distally from 1.25 to 0.50 kgf/cm(2) at 89.1 N and 4.57 to 1.29 kgf/cm(2) at 178.2 N. CONCLUSIONS: Contact pressures are lowest along the medial trochlea and decrease distally along the lateral trochlea. CLINICAL RELEVANCE: Osteochondral plugs from the medial femoral trochlea may be desirable if trochlear size permits. If harvesting from the lateral femoral trochlea, consider harvesting distally near the sulcus terminalis.

Aged↗
PubMed2003

Expert panel on anterior cruciate ligament case studies.

Anterior cruciate ligament (ACL) reconstructions cannot, and should not, be considered "recipe-driven" or "cookie-cutter" operations. There are multiple variables that must be considered both pre- and intraoperatively in order to execute a successful procedure. The following case studies present a number of challenging situations, many of which do not have a straightforward, or only one, solution. The goal is to provide some ral-life clinical situations in which the reader can "observe" an expert panel of ACL surgeons working through the problems--offering solutions based on science, experience, and intuition.

Adult↗
PubMed2003

Femoral aimer deformation: Potential cause for altered femoral tunnel placement in anterior cruciate ligament surgery.

In this case observational study, a standard commercially available femoral aimer used for endoscopic anterior cruciate ligament (ACL) reconstruction was found to have an abnormal bend in the offset tongue that is normally placed in the over-the-top position for ACL femoral aiming using an endoscopic technique. A standard 3/32-inch Steinmannn pin was placed through the aimer, and the offset distance measured 13 mm instead of the normal 7 mm. If this device had been used, significant error would have occurred, placing the anterior tunnel much more anterior than intended, thus potentially contributing to a surgical failure. The purpose of this case study is to alert physicians to check their femoral aimers to make certain that the offset tongue is parallel, thus assuring accurate placement of the provisional pin.

Anterior Cruciate Ligament↗
PubMed2003

Use of a lateral offset short-leg walking cast before high tibial osteotomy.

The clinical results after high tibial osteotomy for the treatment of symptomatic varus gonarthrosis are unpredictable. Although preoperative gait analysis has been shown to be useful in predicting successful outcome after high tibial osteotomy, there are no readily available preoperative clinical tests for predicting success. The authors did a study to determine the effects of an offset short-leg walking cast as a potential predictor of clinical success after high tibial osteotomy. Specifically, the authors evaluated the effect of an offset short-leg walking cast on pain relief and changes in the peak external adduction moments in patients with symptomatic varus gonarthrosis indicated for high tibial osteotomy. Nineteen consecutive patients indicated for high tibial osteotomy were enrolled and completed the study. All patients had precast gait analysis to determine baseline parameters. Immediately after gait analysis, a short-leg lateral offset walking cast was applied and worn for 3 days to allow time for adaptation. Gait analysis then was repeated. Western Ontario and McMaster Universities Osteoarthritis Index pain scores were obtained before and after the cast was applied. The cast resulted in a mean reduction in pain of 53%, and a mean reduction in the peak external adduction moment of 36% in the 17 of 19 patients who tolerated the cast. The reduction in pain was correlated with the reduction in the peak adduction moment (r = 0.63). The authors conclude that an offset short-leg walking cast results in pain reduction that correlates with changes in external adduction moments about the knee. Therefore, an offset short-leg walking cast may prove to be an effective tool for predicting patients who ultimately will benefit from valgus high tibial osteotomy.

Adult↗
PubMed2002

Anterior cruciate ligament reconstruction with patellar autograft tendon.

There are many techniques, graft choices, and outcome studies evaluating anterior cruciate ligament reconstruction. The current authors specifically look at reconstruction with the patellar tendon from a scientific perspective. Miniopen, endoscopic, and two-incision operative techniques in addition to hamstring versus patellar tendon autograft reconstructions are compared via randomized prospective studies. A review of all studies evaluating arthroscopically-assisted anterior cruciate ligament reconstruction with patellar tendon was conducted. The authors found arthroscopically-assisted anterior cruciate ligament reconstruction to have a high short-term stability rate, extremely high patient satisfaction level, and a low postoperative complication rate. When the endoscopic technique was compared with the two-incision technique, there were no major differences. The difference between patellar tendon and hamstring autograft reconstruction can be described best as subtle, except for the consistent finding of an increased activity level in the patellar tendon group. When the principles of anterior cruciate reconstruction are followed, one can expect consistent results with patellar tendon autograft reconstruction.

Adult↗
PubMedDate not supplied

Normalization of the Constant score.

The strength of the normal shoulder may differ by gender and deteriorate with age. Thus, the Constant score may also decrease in absolute value while still reflecting a normal score. To account for age- and gender-related differences, normal results for this scale must be determined across a population of patients without shoulder disease. Patients presenting for evaluation of nonshoulder conditions participated. A subjective questionnaire was completed. Range of motion and strength were measured. This analysis includes the data of 441 patients. The mean Constant score for men was significantly greater than that for women in each age group ( P < .05). Significant age-related differences were noted in each group ( P < .05). Normative values for the Constant score based on age and gender were determined. The adjusted score represents the gender- and age-matched function of the shoulder and is useful in the evaluation of shoulder outcomes.

Adolescent↗
PubMedDate not supplied

Comparison of ultrasonic suture welding and traditional knot tying in a rabbit rotator cuff repair model.

The purpose of this study is to evaluate ultrasonic suture welding of monofilament suture in an animal model of rotator cuff repair with biomechanical and histologic analyses. We randomly assigned 46 shoulders in 23 rabbits to 1 of 3 treatment groups: sham-operated (n = 15), knotted (n = 15), and welded (n = 16). Supraspinatus defects were surgically created and acutely repaired with suture anchors loaded with either No. 2-0 Ethibond for knotted group or No. 2-0 nylon for welded shoulders. Eighteen weeks postoperatively, all animals were killed, and the shoulders underwent either biomechanical testing or histologic analysis. The maximum stress of the sham-operated group (20.6 N/mm2) was significantly greater than that of both the knotted (10.2 N/mm2) and welded (8.3 N/mm2) groups (P < .05), but no differences were observed between the knotted and welded groups. Although some histologic changes were noted, none was considered to be significant to distinguish either group.

Animals↗
PubMedDate not supplied

Treatment options for articular cartilage defects of the knee.

The treatment of symptomatic articular cartilage defects of the knee has evolved tremendously in the past decade. Previously, there were limited treatment options available to patients who suffered from either partial-thickness or full-thickness cartilage lesions. Because articular cartilage has a limited capacity for healing, patients were often treated symptomatically until they became candidates for osteotomy or total joint replacement. Recently, both reparative and restorative procedures have been developed to address this significant source of morbidity in young active patients. Microfracture is a reparative technique that induces a healing response to occur in an area of articular cartilage damage. Osteochondral autografts and allografts in addition to autologous chondrocyte implantation are restorative techniques aimed at recreating a more normal articular surface. Both types of procedures have been developed to alleviate the symptoms associated with focal chondral defects, as well as limit their potential to progress to a diffuse degenerative arthritis. Treatment can vary depending on both cartilage defect and patient factors. This article summarizes the various treatment options that have recently become available.

Cartilage, Articular↗
PubMedDate not supplied

Arthroscopic anterior cruciate ligament reconstruction: a metaanalysis comparing patellar tendon and hamstring tendon autografts.

BACKGROUND: The best choice of graft tissue for use in anterior cruciate ligament reconstruction has been the subject of debate. HYPOTHESIS: Anterior cruciate ligament reconstruction with patellar tendon autograft leads to greater knee stability than reconstruction with hamstring tendon autograft. STUDY DESIGN: Metaanalysis. METHODS: A Medline search identified articles published from January 1966 to May 2000 describing arthroscopic anterior cruciate ligament reconstruction with either patellar tendon or hamstring tendon autograft and with a minimum patient follow-up of 24 months. RESULTS: There were 1348 patients in the patellar tendon group (21 studies) and 628 patients in the hamstring tendon group (13 studies). The rate of graft failure in the patellar tendon group was significantly lower (1.9% versus 4.9%) and a significantly higher proportion of patients in the patellar tendon group had a side-to-side difference of less than 3 mm on KT-1000 arthrometer testing than in the hamstring tendon group (79% versus 73.8%). There was a higher rate of manipulation under anesthesia or lysis of adhesions (6.3% versus 3.3%) and of anterior knee pain in the patellar tendon group (17.4% versus 11.5%) and a higher incidence of hardware removal in the hamstring tendon group (5.5% versus 3.1%). CONCLUSIONS: Patellar tendon autografts had a significantly lower rate of graft failure and resulted in better static knee stability and increased patient satisfaction compared with hamstring tendon autografts. However, patellar tendon autograft reconstructions resulted in an increased rate of anterior knee pain.

Adult↗
PubMedDate not supplied

Comparison of clinical and dynamic knee function in patients with anterior cruciate ligament deficiency.

BACKGROUND: Whether passive measures of isokinetic muscle strength deficits and knee laxity are related to the dynamic function of the anterior cruciate ligament-deficient knee remains unclear. HYPOTHESES: Arthrometer measurements are not predictive of peak external knee flexion moment (net quadriceps muscle moment), isokinetic quadriceps muscle strength correlates with peak external knee flexion moment (net quadriceps muscle moment), and isokinetic hamstring muscle strength correlates with peak external knee extension moment (net flexor muscle moment). STUDY DESIGN: Cross-sectional study. METHODS: Gait analysis was used to assess dynamic function during walking, jogging, and stair climbing in 44 subjects with unilateral anterior cruciate ligament deficiency and 44 control subjects. Passive knee laxity and isokinetic quadriceps and hamstring muscle strength were also measured. RESULTS: Arthrometer measurements did not correlate with peak external flexion or extension moments in any of the activities tested or with isokinetic quadriceps or hamstring muscle strength. Test subjects also had a significantly reduced peak external flexion moment during all three jogging activities and stair climbing compared with the control subjects and this was correlated with significantly reduced quadriceps muscle strength. CONCLUSIONS: Absolute knee laxity difference did not correlate with dynamic knee function as assessed by gait analysis and should not be used as a sole predictor for the outcome of treatment. Patients with greater than normal strength in the anterior cruciate ligament-deficient limb performed low- and high-stress activities in a more normal fashion than those with normal or less-than-normal strength.

Adult↗
PubMedDate not supplied

Effects of graft rotation on initial biomechanical failure characteristics of bone-patellar tendon-bone constructs.

BACKGROUND: Graft-tunnel mismatch is a potential problem during single-incision technique for anterior cruciate ligament reconstruction with the central third of the patellar tendon. Mismatch is present when the graft is too long to fit appropriately in the tunnels that have been created. Graft rotation is one method for addressing this problem. PURPOSE: To determine the results of graft rotation up to 540 degrees on initial graft biomechanical properties and graft length. STUDY DESIGN: Controlled laboratory study. METHODS: Forty porcine bone-patellar tendon-bone constructs were divided into four groups and constructs were rotated to 0 degrees, 90 degrees, 180 degrees, and 540 degrees, respectively, for each group. Biomechanical testing to failure was performed with the constructs under tension at an elongation rate of 5 cm/sec. Lengths were measured after a 1-kg load was applied to the grafts. RESULTS: No statistical difference in ultimate failure strength was encountered between any of the groups (P = 0.915). The grafts that were twisted to 540 degrees shortened an average of 5.41 mm, which represented an average shortening of 10% of the initial tendon length. CLINICAL RELEVANCE: Graft rotation up to 540 degrees does not result in loss of initial graft strength, and may be a solution for graft-tunnel mismatch.

Animals↗