bluuebunny/crossref_metadata_2025 huggingface dataset:
An outbreak of furunculosis among high school athletes
Authors: Sosin Daniel M. , Gunn Robert A. , Ford Wesley L. , Skaggs Joseph W.
Published: June 2007

Furuncles (boils) are common among teenagers; how ever, few outbreaks have been documented. We inves tigated an outbreak of furuncles that occurred among male athletes of a Kentucky high school during the 1986 to 1987 school year. The overall attack rate was 25% (31/124). The risk of developing a furuncle in creased two to three times in those who had skin injury. Athletes who sustained abrasions more than twice per week ( P < 0.01), who had a cut that required bandaging ( P = 0.01), or had an unspecified injury causing a missed practice or game ( P = 0.04) were at increased risk. The risk of developing furunculosis did not appear to be related to contact with fomites, but rather, to contact with furuncles. Although athletes shared com mon areas (showers, locker rooms, practice areas), the attack rates for varsity football (36%) and varsity bas ketball (33%) were four times greater than for nonvars ity teams ( P < 0.01). Players who had a friend with a furuncle were more than twice as likely to also have had a furuncle ( P < 0.01). Exposure to furuncles ap peared to increase the risk of furunculosis independ ently of reported skin injury. Control and prevention should, therefore, focus on both reducing skin injury and reducing exposure to furuncles, rather than at tempting to sterilize inanimate objects.
The effect of enforced exercise on the healing of ligament injuries
Authors: Burroughs Paul , Dahners Laurence E.
Published: June 2007

Previous studies have documented that mobilization ad libitum has a beneficial effect on the healing of ligaments as compared to immobilization. This study was under taken to determine whether enforced exercise (over and above motion ad libitum) would have a further beneficial effect or, instead, an adverse effect on the healing of ligaments.

Large male Sprague-Dawley rats with unrepaired transections of the medial collateral ligament were sep arated into five groups of similar mean weights. Two of these groups had the anterior cruciate ligament and the medial capsule transected in addition to the medial collateral ligament, rendering the knee unstable. The groups were then subjected to varying regimens of enforced exercise (swimming). After 12 days, the me chanical characteristics of the femur, medial collateral ligament, and tibia complex were evaluated. Rats with intact secondary valgus stabilizers (medial capsule and anterior cruciate ligament) that swam daily for either 5 (moderate) or 15 (near exhaustion) minutes were found to have increases in the tensile strength of the femur, medial collateral ligament, tibia complex as compared to rats that did not swim. Unstable knees (with tran sected secondary valgus stabilizers) did not show an increase in the tensile strength of the femur, medial collateral ligament, tibia complex when subjected to moderate increase in enforced exercise (swimming 5 minutes). The unstable groups were, however, signifi cantly more lax than the groups that underwent identi cal exercise regimens but had intact secondary valgus stabilizers. Significant differences in the stiffness of the ligaments in the different groups were not detected.

In conclusion, exercise had a beneficial effect on the strength of the medial collateral ligament in stable rat knees but an adverse effect on the laxity of the MCL when the knees had been rendered unstable.
Medial approach in elbow arthroscopy
Authors: Lindenfeld Thomas N.
Published: June 2007

The author undertook a cadaveric dissection study to confirm the hypothesis that starting with the anterior medial portal in elbow arthroscopy is safer than starting with the anterior radial portal.

In six cadaveric elbows, the capsule was distended with saline. Both anterior medial and anterior radial approaches were made with the elbow flexed to 90°. Four and one-half millimeter arthroscopic sheaths were inserted and obturators were then left in place while the saline was drained; expanding polyurethane foam was used to distend the capsule. We allowed the polyurethane foam to harden and then dissected all elbows, with special attention given to exposure of the radial and medial nerve and the brachial artery.

The hardened foam allowed for continued capsular distension during these dissections and recreated nor mal distances from instrument portals to neurovascular bundles. The minimum distance from the path of the arthroscopic sheath to the large neurovascular struc tures was then measured. The distance from the medial portal to the nearest neurovascular structure (median nerve, brachial artery) averaged 23 mm. The distance from the radial portal to the nearest neurovascular structure (radial nerve) averaged 3 mm. The ulnar nerve averaged a 25 mm clearance from the medial portal. Even when the medial portal was made by an incorrect method, the minimum clearance to the median nerve averaged 11 mm.

The most frequently recommended current standard technique for elbow arthroscopy involves beginning with an anterior radial portal. However, the findings in this study suggest that an anterior medial portal is a superior starting point. The medial portal allows good visualization of the joint and helps with safe and accu rate placement of the radial portal. Most importantly, the medial portal may be placed a safe distance from important neurovascular bundles.
Shoulder arthroscopy: its role in evaluating shoulder disorders in the athlete
Authors: Hurley John A. , Anderson Thomas E.
Published: June 2007

We retrospectively reviewed 100 initial shoulder ar throscopies from a general sports medicine orthopaedic practice to determine if arthroscopy is helpful diagnos tically and to see if specific lesions correlate well with specific diagnoses. Seventy-two percent of the patients in the review had glenoid labral tears. Ninety-two per cent of patients who had a diagnosis of either recurrent anterior dislocation or recurrent anterior subluxation demonstrated a tear of the anterior inferior margin of the glenoid labrum. Sixty-eight percent of patients with a diagnosis of impingement demonstrated tears at the superior margin of the labrum. There was a significant difference between throwing and nonthrowing athletes. Partial rotator cuff tears were noted in 18 patients, the majority occurring in throwing athletes. Other abnor malities, such as degenerative joint changes and biceps tendon lesions, were also noted at the time of arthros copy.

A large number of glenoid labral tears found at the time of arthroscopy appeared to be associated with conditions other than instability, which may or may not affect the throwing athlete. There also appeared to be a high correlation between tears in the anterior inferior glenoid labrum and anterior instability. Arthroscopy en abled us to identify other significant information about the status of the biceps tendon or the undersurface of the rotator cuff. These are areas in which problems might otherwise have been missed. Degenerative changes of the articular surface, not apparent on plain radiographs, may also be better evaluated arthroscop ically.
The iliotibial band lateral sling procedure and its effect on the results of anterior cruciate ligament reconstruction
Authors: O'Brien Stephen J. , Warren Russell F. , Wickiewicz Thomas L. , Rawlins Bernard A. , Allen Answorth A. , Panariello Robert , Kelly Anne M.
Published: June 2007

The effect of iliotibial band "lateral sling" augmentation on long-term outcome in ACL reconstruction using free autogenous central-third patellar tendon was evaluated retrospectively. Eighty reconstructions were reviewed; the minimum followup was 2 years and the average was 4 years. Sixty percent of the procedures involved supplementation with a lateral sling. By both clinical evaluation and KT-1000 measurement, there were no differences in the results of patients with lateral sling augmentation and those without it. In addition, 40% of patients had chronic pain and/or swelling related to the lateral sling. We do not currently recommend the routine use of a lateral sling augmentation for ACL reconstruc tion using central-third patellar tendon.
Physician care for interscholastic athletes in Michigan
Authors: Lindaman Lynn M.
Published: June 2007

Between January 1989 and March 1989 the athletic directors of the 711 high schools in the Michigan High School Athletic Association were surveyed as to what sports and levels of competition each school offered and what level of medical care was available. Fifty- seven percent of the surveyed schools returned prop erly completed forms. Sixty-one percent of the schools responding reported having a physician available for at least one team at some time during the year. This was almost universally the football team; with 59% of the schools with varsity football reporting a physician pres ent at either a practice or a contest at least once during the year. Only 13% of the schools reported having a physician available for a team other than varsity football. Seventy-four percent of all varsity teams had neither a physician nor an athletic trainer present at any time during the year.

Comparison of the results of this study with similar studies performed in Michigan in 1975 and 1979, as well as studies in other states, demonstrates that de spite the increased awareness and popularity of sports medicine, there has been no appreciable change in the amount of access interscholastic athletes have to phy sician care.
Results of knee manipulations after anterior cruciate ligament reconstructions
Authors: Dodds Julie A. , Keene James S. , Graf Ben K. , Lange Richard H.
Published: June 2007

We analyzed the results of knee manipulations in 42 knees that had persistent flexion or extension deficits after intraarticular ACL reconstructions. All manipula tions were done under a spinal or general anesthetic and, in 10 cases, arthroscopic debridement of adhe sions also was performed. The average time from re construction to manipulation was 7 months (range, 3 to 14 months) and the average followup was 26 months (range, 6 to 56 months). At manipulation, average flex ion was increased from 95° to 136° and average ex tension from 11° to 3°. In no case was motion gained at the expense of joint stability and, at final followup, average flexion and extension were 127° and 4°, re spectively. The final range of motion achieved was not affected by the time to manipulation, severity of pre manipulation flexion deficit, or concomitant arthro scopic debridement of adhesions. However, knees with premanipulation extension deficits of ≥15° achieved significantly less final extension than knees with lesser premanipulation deficits. Overall, manipulations were a safe and effective method for improving both flexion and extension in 86% of the knees that had restricted motion after ACL reconstructions.
The effects of increased tension on healing medial collateral ligaments
Authors: Gomez Mark A. , Woo Savio L.-Y. , Amiel David , Harwood Frederick , Kitabayashi Linda , Matyas John R.
Published: June 2007

The effects of motion and increased levels of stress on the biomechanical, biochemical, and morphological properties of healing medial collateral ligaments were assessed in a rabbit model. In one group, the medial collateral ligament of the left hindlimb was transected and allowed to heal with cage activity for either 6 or 12 weeks. In another group, the transected ligaments were permitted to heal for 4 weeks and then were placed under increased stress by inserting a stainless steel pin perpendicularly underneath the healing medial collateral ligament. The animals were allowed cage activity for an additional 2 or 8 weeks. The varus-valgus joint laxity and the stress-strain properties of the medial collateral ligament substance were obtained. Further, the quan tity of total collagen, amount and ratio of the collagen cross-links, dihydroxylysinonorleucine and hydroxyly sinonorleucine, and the histologic appearance of the healing medial collateral ligaments were evaluated for all groups. At 6 weeks, knees with a transected medial collateral ligament were twice as lax as the controls. However, joints with the stainless steel tension pin had varus-valgus values approximately 1.5 times those of the controls. At 12 weeks, joints with increased stress were not statistically different from the controls. The group that had healing with increased stress for 12 weeks produced the highest stress for a given strain compared to any other group. Also, the total collagen levels and the ratio of dihydroxylysinonorleucine/hy droxylysinonorleucine were the closest to normal of any transected group. Finally, qualitative histologic improve ments were seen, including a more longitudinal arrange ment of collagen fibers and decreased cellularity.
Partial rupture of the patellar ligament
Authors: Karlsson Jon , Lundin Olof , Lossing Ingrid Wigerstad , Peterson Lars
Published: June 2007

Partial rupture of the patellar ligament, also known as jumper's knee, is defined as a repetitive overload lesion at the bone-ligament junction at the lower patellar pole. It is found mainly in athletes and is caused either by microruptures or partial macroruptures of the proximal part of the ligament. The abnormal anatomical lesion is focal degeneration, microruptures and macroruptures, and devitalized tissue at the insertion of the patellar ligament. Proliferation and neovascularization are often found, as well as degeneration and incomplete tissue healing. Surgical treatment is indicated only if a pro longed and well-supervised conservative treatment pro gram fails. We operated on 78 patients with jumper's knee, by carefully removing the abnormal tissue from the ligament. At follow-up examination, 71 of 78 pa tients had excellent or good functional results and complete resumption of sports activities. Objective measurements of thigh muscle strength using a Cybex II dynamometer correlated with the functional results at a low angular velocity.
Arthroscopic treatment of anterolateral impingement of the ankle
Authors: Ferkel Richard D. , Karzel Ronald P. , Del Pizzo Wilson , Friedman Marc J. , Fischer Scott P.
Published: June 2007

We studied 31 patients (17 females, 14 males; average age, 34) with more than 2 years of followup who had chronic anterolateral ankle pain following inversion in jury. All had failed to respond to at least 2 months of conservative treatment and had negative stress radio graphs to rule out instability. On physical examination, tenderness was localized to the anterolateral corner of the talar dome. Magnetic resonance imaging was the most useful diagnostic screening test, showing synovial thickening consistent with impingement in the antero lateral gutter. At an average of 24 months after injury, all patients underwent ankle arthroscopy, which showed proliferative synovitis and fibrotic scar tissue in the lateral gutter, often with associated chondromalacia of the talus. Operative arthroscopic treatment consisted of partial synovectomy with debridement of scar tissue from the lateral gutter. Postoperatively, patients walked with crutches allowing weightbearing as tolerated. Av erage return to sports was 6 weeks. Histopathologic analysis performed on the resected tissue showed syn ovial changes consistent with chronic inflammation. Results of treatment after at least 2 year followup were 15 excellent, 11 good, 4 fair, and 1 poor. Since there are several distinct causes of chronic ankle pain, we prefer to call this problem "anterolateral impingement of the ankle" and believe the term "chronic sprain pain" should be discarded.
The accuracy of three-dimensional magnetic resonance imaging in the diagnosis of ruptures of the lateral ligaments of the ankle
Authors: Verhaven Eddy F.C. , Shahabpour Maryam , Handelberg Frank W.J. , Vaes Peter H.E.G. , Opdecam Pierre J.E.
Published: June 2007

In a prospective study, the diagnostic accuracy of three- dimensional magnetic resonance imaging in the evalu ation of ruptures of the lateral ligaments of the ankle was determined by comparing three-dimensional mag netic resonance findings with operative findings. In a series of 18 consecutive cases of acute significant inversion trauma to the ankle, a three-dimensional fast imaging with steady-state precession pulse sequence (3D FISP) was performed. The study included only those cases in which views showed a difference in talar tilt of 15° or more, and a difference in anteroposterior drawer of 10 mm or more between the imaged and the normal ankle. All ankles were scheduled for surgical exploration. Compared with operative findings, the sen sitivity, specificity, and accuracy of 3D FISP imaging were, respectively, 100%, 50%, and 94.4% for ruptures of the anterior talofibular ligament and 91.7%, 100%, and 94.4% for ruptures of the calcaneofibular ligament. We believe that 3D FISP magnetic resonance imaging is a noninvasive, fast, and very accurate diagnostic aid to operative planning for double ligament tears in younger competitive athletes.
Force displacement characteristics of the posterior cruciate ligament
Authors: Bach Bernard R. , Daluga Daniel J. , Mikosz Richard , Andriacchi Thomas P. , Seidl Robert
Published: June 2007

The percent force changes in the posterior cruciate ligament were calculated using a previously validated computerized knee model after the femoral insertion sites were varied 2.5 and 5.0 mm in an anterior, pos terior distal, anterior distal, and posterior distal direc tion. The tibial insertion sites were also varied 2.5 and 5.0 mm in the medial, lateral, proximal, and distal direc tions. Percent force changes were measured over a range of 0° to 90°. These insertion sites simulated potential surgical placement errors.

Results of this study demonstrated that the greatest percent force changes in the posterior cruciate ligament were at full extension. The greatest absolute percent force change between 0° and 90° of flexion was with a femoral insertion of the posterior cruciate ligament placed 5 mm anterior to its normal attachment site, which resulted in a 39% change in the posterior cruciate ligament force. Distal femoral site attachment had the least effect (10% at 5.0 mm). Alterations at the tibial attachment site were less sensitive than on the femur; the greatest absolute percent force changes occurred with medial and lateral attachment sites (14% and 15%, respectively, at 5.0 mm). A minimal amount of percent force changes were seen between 45° and 75° of knee flexion in all positions tested for both tibial and femoral attachment sites.

This model suggests that, like the anterior cruciate ligament, the force in the posterior cruciate ligament is also sensitive to attachment site position. As in anterior cruciate ligament studies, the femoral attachment site was found to be more sensitive. The greatest percent force changes for the posterior cruciate ligament were seen at the extremes of the knee motion tested (i.e., 0° and 90°). The posterior cruciate ligament sensitivity to graft placement lends credence to the importance of anatomic reconstruction. Results of this study can also be extrapolated to help in designing early continuous passive motion and rehabilitation programs, with the safest range of knee motion between 45° and 75°.
The effect of a meniscal prosthesis on knee biomechanics and cartilage
Authors: Sommerlath Karola , Gillquist Jan
Published: June 2007

A meniscal prosthesis made of Dacron with polyure thane coating was tested as a substitute for the medial meniscus in a rabbit experimental model concentrating on biomechanical behavior of the knee joint and gross and histologic evaluation 3 months after surgery. The results were compared to sham-operated knees, knees with a peripheral incision of the medial meniscus, and knees with a total meniscectomy. Knees with prosthe sis implantation had the same stiffness as knees with sham-operation or meniscal incision, but knees with meniscectomy were stiffer (P < 0.05). Knees with pros thesis showed lower energy storage during relaxation than knees with sham-operation or meniscal incision (P < 0.05). Energy storage in the prosthesis group was similar to the meniscectomy group. Partial or total ingrowth of synovial tissue into the prosthesis was present in 93%, and 63% of the incised menisci had healed. Cartilage changes were present in 70% of the prosthesis group, in 25% of the knees with meniscal incision, and in all knees with meniscectomy. The sham- operated knees were free from cartilage degeneration. Knees with prosthesis had the same frequency of car tilage changes on the femur, but had less changes on the tibia compared to knees with meniscectomy. A high rate of osteophyte formation was observed after pros thesis implantation as well as following meniscectomy, but the osteophytes were larger in the prosthesis group (P < 0.01). The most frequent and severe effect on the synovium was found in the prosthesis group (92%), but no foreign body reaction or loose Dacron particles were found. The Dacron prosthesis had a cartilage-protecting effect, but the biomechanical behavior of the knee joint was similar to meniscectomy. Knees with peripheral meniscal incision were similar to sham-operated knees.
Instrumented evaluation of knee laxity: A comparison of five arthrometers
Authors: Anderson Allen F. , Snyder Robert B. , Federspiel Charles F. , Lipscomb A. Brant
Published: June 2007

We performed a prospective study on 50 subjects with normal knees and 50 patients with chronic unilateral disruption of the anterior cruciate ligament. In a random ized testing sequence, both groups were examined with five arthrometers: the MEDmetric KT-1000, the Stryker Knee Laxity Tester, the Acufex Knee Signature System, the Dyonics Dynamic Cruciate Tester, and the Genucom Knee Analysis System. Each examination was performed according to protocol with the knee at 30° of flexion.

The total anterior laxity measurements of the normal subjects using the Dyonics Dynamic Cruciate Tester and Acufex Knee Signature System were approxi mately half of the KT-1000, Stryker, and Genucom values. A comparison of the side-to-side measurements revealed no statistically significant difference in the values of the five arthrometers. However, the Genucom showed an unacceptably high number of normal sub jects with laxity values that suggested an anterior cru ciate ligament tear.

Total anterior laxity measurements of the anterior cruciate ligament deficient knees were almost twice those of normal knees with each device except the Genucom. Comparison of the mean side-to-side differ ence in the patients with ACL deficiency demonstrated statistically significant differences in the values re corded with the five arthrometers. The side-to-side difference was greatest with the KT-1000 and least for the KSS. In the 89 N Lachman test, the KT-1000 and Stryker demonstrated the highest diagnostic accuracy. The maximumm manual test improved the accuracy of each device.
The effects of anabolic steroids on collagen synthesis in rat skeletal muscle and tendon
Authors: Karpakka Jarmo A. , Pesola Maija K. , Takala Timo E.S.
Published: June 2007

We measured the activities of prolyl 4-hydroxylase and galactosylhydroxylysyl glucosyltransferase (both en zymes of collagen biosynthesis) and the concentration of hydroxyproline in male rat soleus muscle and Achilles tendon during anabolic steroid treatment at 1 and 3 weeks. The rats were treated using a therapeutic dos age or a dosage that was five times the therapeutic level. After 1 week, the activity of prolyl 4-hydroxylase decreased significantly (P < 0.01) in both treated groups in the soleus muscle, but the activity of galac tosylhydroxylsyl glucosyltransferase decreased signifi cantly (P < 0.05) only in the group given a therapeutic dose. After 3 weeks, the activities were at the control level. In the Achilles tendon, the activity of prolyl 4- hydroxylase and the hydroxyproline concentration de creased significantly (P < 0.05) in the group given high doses at 3 weeks. Anabolic steroid treatment seems to have at least a transitory effect on collagen biosyn thesis in male rat muscle and tendon; in tendon this effect is seen only with high doses.
Arthroscopic meniscectomy in patients over the age of 40
Authors: Bonamo John J. , Kessler Kevin J. , Noah Joseph
Published: June 2007

One hundred eighteen patients, aged 40 or older, underwent partial meniscectomy and limited debride ment of coexisting grade III or grade IV degenerative articular cartilage lesions. No curettage, abrasion ar throplasty, or subchondral drilling was performed. The average age of the patients was 57 years (range, 40 to 78). The mean followup was 3.3 years (range, 1 to 7). Sixty-three similar patients who also underwent partial meniscectomy but did not have the finding of significant coexisting articular surface erosion were studied for comparison.

Of the 118 patients in the group with articular lesions (78 men and 40 women), 71 (60%) rated their improve ment as significant, 22 (19%) as moderate, and 15 (13%) as mild; 10 (8%) noted no improvement. Although 98 (83%) were generally satisfied with their result, only 57 (48%) reported satisfaction for sports. However, 89 (75%) had resumed and continued recreational athletic activities. Results tended to be worse in women, in patients older than 60, in those with moderate or severe tibiofemoral radiographic changes, those who had a grade IV articular lesion, and those with longer follow up time.

Although results were poorer in patients with coex isting grade III or grade IV degenerative arthritis, ar throscopic partial meniscectomy and limited debride ment was an acceptably effective procedure in patients over the age of 40.
The repair of osteochondral defects using an exogenous fibrin clot
Authors: Paletta George A. , Arnoczky Steven P. , Warren Russell F.
Published: June 2007

To evaluate the ability of an exogenous fibrin clot to hasten or optimize the repair of full-thickness articular cartilage defects, 4-mm diameter, full-thickness articu lar cartilage defects in 20 adult mongrel dogs were packed with an exogenous fibrin clot that had been prepared from each animal. The defects were created in a loaded and unloaded portion of the femoral troch lea. The healing response was then examined using routine histology at various intervals from 2 weeks to 6 months.

Both the experimental (clot-filled) and control (empty) defects healed through a proliferation of fibrous con nective tissue that eventually modulated into fibrocar tilage. However, in the 2-, 4-, and 8-week animals, the experimental defects (both loaded and unloaded) dem onstrated a more organized and advanced healing re sponse than did the control defects. This difference was less pronounced in the 12- and 24-week animals. In all specimens, the clot-filled defects healed more uniformly than controls with less surface depression. In general, the unloaded sites were more uniform in heal ing than the corresponding loaded sites.
Magnetic resonance imaging of the posterior cruciate ligament
Authors: Gross Michael L. , Grover Jaswinder S. , Bassett Lawrence W. , Seeger Leanne L. , Finerman Gerald A.M.
Published: June 2007

This study was undertaken to determine the accuracy of magnetic resonance image scanning in detecting posterior cruciate ligament injury, and to determine those clinical situations where it can add the most useful information. A retrospective study was conducted on 201 patients who underwent surgery after magnetic resonance scanning of their knees. Two additional pa tients who did not have surgery but had clinical findings grossly positive for posterior cruciate ligament injury were included in the analysis of magnetic resonance imaging accuracy. In all, there were 190 intact and 13 torn posterior cruciate ligaments. In a review of the clinical findings in the 11 patients with surgically docu mented tears, we found that all 11 had positive mag netic resonance scans. In 4 of the 11, magnetic reso nance imaging provided especially useful information regarding the status of the ligament. For the 190 normal ligaments, there were no false-positive scans; for the 13 torn ligaments, there were no false-negative scans. Therefore, specificity and sensitivity estimates for this group were both 100%.

Magnetic resonance imaging proved to be an accu rate modality for evaluating the integrity of the posterior cruciate ligament. If used in the proper setting, it can provide useful information for diagnosing posterior cru ciate ligament injuries.
Isometric versus tension measurements
Authors: Fleming Braden , Beynnon Bruce D. , Johnson Robert J. , McLeod William D. , Pope Malcolm H.
Published: June 2007

This study was designed to compare the displacement patterns of an isometer, used to determine graft place ment during reconstruction, with the actual tensions on an anterior cruciate ligament substitute. In cadaveric specimens, a Kevlar anterior cruciate ligament substi tute was implanted in three separate femoral sites, each of which was subsequently fixed to two different tibial sites. The initial tension of the Kevlar substitute was set to 22 or 33 N at 20° of knee flexion. The displacement patterns for each position were recorded during passive flexion-extension using the isometer. Using a custom-designed tensiometer, the tensile forces on the substitute after rigid fixation at the tibia and femur were measured. During passive flexion-ex tension, the maximum change in tension of the anterior cruciate ligament substitute, measured by the tensiom eter, was correlated with the maximum change in dis placement between attachment sites, measured by the isometer. The coefficient of determination was equal to 0.15, indicating that the isometer may not accurately predict the tensions developed in the substitute.
Arthroscopically assisted anterior cruciate ligament reconstruction with the pes anserine tendons
Authors: Sgaglione Nicholas A. , Del Pizzo Wilson , Fox James M. , Friedman Mark J.
Published: June 2007

Fifty anterior cruciate ligament-deficient knees treated consecutively with arthroscopically assisted recon struction using a pes anserine tendon autograft were retrospectively studied. The mean followup was 36.7 months (range, 26 to 58). All patients had reconstruc tion with a double-stranded graft. The mean injury to surgery interval was 9.6 days in 22 patients (acute group) and 22.5 months in 28 patients (chronic group). Objective outcome, which was noted to be more opti mal in the acute group, was better than subjective outcome in either group. Examination revealed 95% of patients treated acutely and 82% of those treated later to have 1 + or less Lachman test result ( P < 0.036) and 96% of the acute group and 82% of the chronic group to have an absent pivot shift ( P < 0.036). Eighty-eight percent of acutely treated patients had a KT-1000 result of ≤3 mm, as compared to 61% of chronically treated patients ( P < 0.001). Loss of range of motion was significantly greater in the acute group ( P < 0.018). Using a strict overall rating system, patients recon structed earlier were noted to have a better outcome compared to those after delayed reconstruction ( P < 0.021). Cumulative meniscal injury appears to be the most significant contributing factor.
Arthroscopic and histologic analysis of human patellar tendon autografts used for anterior cruciate ligament reconstruction
Authors: Rougraff Bruce , Shelbourne K. Donald , Gerth P. Kevin , Warner Jeffrey
Published: June 2007

To evaluate the fate of patellar tendon autografts in humans, the knees of 23 patients who had undergone anterior cruciate ligament reconstruction were exam ined 3 weeks to 6.5 years postoperatively. Arthroscopy and biopsy were performed on all patients.

The patellar tendon autografts progressed through four stages of ligamentization after reconstruction. The first stage of repopulation occurred during the first 2 months and was evidenced by a viable 3-week speci men with an increasing fibroblast number and active nuclear morphology. Over the next 10 months, the graft went through a stage of rapid remodeling in which the fibroblast count increased markedly, the active nuclear morphology and neovascularity remained increased, and more areas of degeneration were present as the percentage of mature collagen decreased. The third stage or "maturation" stage occurred over the next 2 years and was characterized by a slow decline in the nuclei and the maturation of the collagen matrix. By 3 years the grafts were ligamentous by all histologic criteria examined.

The authors conclude that human autogenous patel lar tendon grafts are viable as early as 3 weeks post operatively and may not go through a necrotic stage. They then progress through a prolonged process of ligamentization that takes as long as 3 years to com plete.
Relationship between changes in length and force in in vitro reconstructed anterior cruciate ligament
Authors: Muneta Takeshi , Yamamoto Haruyasu , Sakai Hiroshi , Ishibashi Toshiro , Furuya Kohtaro
Published: June 2007

The effect of tibial and femoral attachment site on the length change and force of an anterior cruciate ligament graft during unloaded flexion in eight cadaver speci mens was examined. Two tibial sites (anteromedial and central portion of the anterior cruciate ligament attach ment) and three femoral sites (anterior and central portions of the anterior cruciate ligament attachment, and over-the-top) were evaluated. Graft length changes between all combinations of attachment sites were measured from full extension to 150° of passive flexion at 15° intervals using the displacement of a 2-mm inextensible cord. The anterior cruciate ligament was then reconstructed using a Kennedy Ligament Aug mentation Device, and graft forces at the same angles of passive flexion were measured with a buckle trans ducer.

Graft length change and force were more affected by the femoral attachment site than the tibial site. There was a close correlation between length change and force measurements in flexion, but not near extension. The pattern of force and length change versus flexion angle for a given combination of attachment sites some times varied over the knees tested. Our results suggest that intraoperative isometry measurements are worth while for indicating an overloaded graft in flexion; how ever, length changes near extension may not ade quately reflect graft force, creating the possibility that a graft may be more highly loaded than realized.
Arthrography for the diagnosis of acute lateral ligament injuries of the ankle
Authors: Raatikainen Timo , Puranen Jaakko
Published: June 2007

Arthrography was used for diagnosis of ruptures of lateral ligaments in 589 acutely injured ankles that were treated operatively. The accuracy of the method was tested comparing the findings of arthrography with those at operation. We found arthrography to be almost 100% reliable for diagnosing a fresh anterior talofibular ligament rupture. The best criterion for detecting cal caneofibular ligament rupture was filling of the peroneal tendon sheath with contrast medium. Leakage below and behind the lateral malleolus, when present with peroneal tendon sheath filling, confirms the diagnosis of calcaneofibular ligament rupture, but these findings without peroneal tendon sheath filling are too rare to base the diagnosis on them alone.
Biceps tendon tenodesis for posterolateral instability of the knee
Authors: Wascher Daniel C. , Grauer J. David , Markoff Keith L.
Published: June 2007

The effects of biceps tendon tenodesis on internal- external and varus-valgus laxity were measured using fresh-frozen cadaveric specimens that had undergone sequential sectioning of the posterolateral structures and of the fibular collateral ligament. Tenodesis (using 89 N graft tension and a fixation point located 1 cm anterior to the fibular collateral ligament's insertion on the femur) was effective in restoring external rotation and varus laxity; the procedure actually overcon strained external tibial rotation at all flexion positions and varus angulation at 60° and 90° of flexion. Internal rotation and valgus laxity were unaffected by the teno desis procedure. The anterior fixation point was more effective in reducing laxity than a fixation point located 1 cm proximal to the fibular collateral ligament insertion. Tenodesis using the proximal fixation point, which was nonisometric, did not restore external rotation and varus laxities to intact values at 60° and 90° of knee flexion. Graft tension (45 or 89 N) had no measurable effect on the results of the tenodesis. This study has demonstrated that the biceps tenodesis procedure is effective for reducing static laxity in the knee with posterolateral instability.
Intercondylar notch size and anterior cruciate ligament injuries in athletes
Authors: Souryal Tarek O. , Freeman Tandy R.
Published: June 2007

Published reports agree that there is a strong associa tion between intercondylar notch stenosis and anterior cruciate ligament injuries. In a previously published retrospective study on bilateral anterior cruciate liga ment injuries and associated intercondylar notch ste nosis, we formulated the notch width index to measure and compare intercondylar notch width. The purpose of this prospective study was to establish a normal range for the notch width index and to correlate inter condylar notch size and anterior cruciate ligament in juries. We gathered data on 902 high school athletes, including range of motion, thigh girth, ligament stability and intercondylar notch width using the notch width index. The population was then followed prospectively and anterior cruciate ligament injuries were recorded and correlated with notch width index in a blind manner. Two-year results showed that the overall anterior cru ciate ligament injury rate was 3%. The normal intercon dylar notch ratio was 0.231 ± 0.044. Intercondylar notch width index for men was larger than that for women. Athletes sustaining noncontact anterior cru ciate ligament tears have statistically significant inter condylar notch stenosis (notch width index, 0.189). Ten of 14 athletes with noncontact anterior cruciate liga ment injuries had a notch width index that was at least 1 SD below the mean. Athletes with contact anterior cruciate ligament injuries had a mean of 0.233. We conclude that athletes with a stenotic intercondylar notch are at significantly greater risk for sustaining noncontact anterior cruciate ligament injury.
Anatomic considerations in harvesting the semitendinosus and gracilis tendons and a technique of harvest
Authors: Pagnani Michael J. , Warner Jon J.P. , O'Brien Stephen J. , Warren Russell F.
Published: June 2007

Although the semitendinosus and gracilis tendons have long been used in ligamentous reconstruction proce dures of the knee, their anatomic relationships have not been explicitly detailed. Therefore, cadaveric dissec tions were performed on fresh-frozen adult knees to examine these relationships. Several key anatomic points are useful in the harvest of these tendons. Their conjoined insertion site is medial and distal to the tibial tubercle. They become distinct structures at a point that is farther medial and slightly proximal. Tendon harvest is facilitated by identifying the tendons proximal to this point. The superficial medial collateral ligament lies deep to the tendons in this area and should not be disturbed. The tendons are ensheathed in a dense fascial layer that may impede tendon stripping. The accessory insertion of the semitendinosus tendon (which was present in 77% of the knees dissected) should be identified and transected to avoid tendon damage at harvest. Knee flexion may reduce the risk of injury to the saphenous nerve as it crosses the gracilis tendon. Variation in tendon diameter affects graft strength.
Upper trunk brachial plexopathy
Authors: Markey Keith L. , Di Benedetto Margaret , Curl Walton W.
Published: June 2007

This study was designed to determine the cause of upper trunk brachial plexopathy, which is referred to as a "stinger" or a "burner." This injury often has been thought to occur secondary to traction when an athlete sustains a lateral flexion injury of the neck. At the United States Military Academy, a 4-phase study was begun with 261 tackle football players (236 intramural- and 25 varsity-level players) to investigate this injury. Electro myography and nerve root stimulation studies were used to delineate the lesion, which was found in a total of 32 players who continued throughout the study. This study demonstrated that a much more common mech anism of injury resulting in the stinger syndrome is probably compression of the fixed brachial plexus be tween the shoulder pad and the superior medial scapula when the pad is pushed into the area of Erb's point, where the brachial plexus is most superficial. An or thosis was designed to protect the brachial plexus from the compressive force of the shoulder pad. In prelimi nary trials, this orthosis had been very effective in decreasing the number of episodes in which stinger injuries occurred.
The natural history of meniscal tears in anterior cruciate ligament insufficiency
Authors: Keene Gregory C.R. , Bickerstaff Derek , Rae Paul J. , Paterson Roger S.
Published: June 2007

We reviewed the meniscal status of 176 consecutive patients undergoing anterior cruciate ligament recon struction acutely (less than 6 weeks from injury), sub- chronically (6 weeks to 12 months from injury), and chronically (more than 12 months from injury). The commonest tear was the single longitudinal vertical split of the medial meniscus. There was an increasing inci dence of meniscal tears as the injury became more chronic, with a significant (P < 0.001) increase in medial meniscal tears; the incidence of lateral meniscal tears remained relatively constant.

Seventy-five (43%) of the patients had one or both menisci repaired. Acutely, repair was performed more frequently on the medial meniscus than the lateral (80% versus 24%, respectively). All repaired menisci had single longitudinal tears unstable to probing. The inci dence of repair dropped to 46% in the medial meniscus and 14% in the lateral meniscus in the chronic stage.

Nineteen (25%) of these 75 patients (26 menisci) underwent a check arthroscopy at a minimum of 6 months from repair. All 21 medial menisci and all 5 lateral meniscal tears had healed; however, 1 lateral meniscus had torn along the line of the sutures.

At an average followup of 40 months, 92% of the repaired menisci were still in situ and 8% that had required resection were related to the recurrence of anterior cruciate ligament instability.

This study highlights the increasing incidence of men iscal injury in chronic anterior cruciate ligament insuffi ciency with the meniscal tears becoming more complex and therefore less amenable to suture. We recommend that patients with anterior cruciate ligament instability be investigated for repairable meniscal tears and that ligament stabilization of the knee and meniscal sutures be considered early.
Does Cybex testing increase knee laxity after anterior cruciate ligament reconstructions?
Authors: Maitland Murray E. , Lowe Ron , Stewart Susan , Fung Tak , Bell G. Douglas
Published: June 2007

Long-term stability of the knee after anterior cruciate ligament reconstruction is imperative. Testing protocols that use isokinetic systems are commonly performed despite controversies as to their safety. The purpose of this study was to test whether one episode of isokinetic testing would cause an increase in anterior tibial translation. Twenty-four subjects who had anterior cruciate ligament recontructions 153 to 300 days earlier volunteered for the study. Initially, subjects walked on a treadmill at 5 km/hr for 10 minutes to test the effect of exercise on displacement measurements. One week later, subjects performed a maximal knee flexion-exten sion test on the Cybex dynamometer at 60, 150, and 240 deg/sec. Anterior tibial displacement at 133.5 N was obtained from force-displacement curves pro duced by KT-2000 arthrometer testing at nine intervals: before exercise on the treadmill, at four intervals after treadmill exercise, and at four intervals after Cybex testing. Repeated measures analysis of variance did not show a significant exercise effect, interaction be tween type of exercise and time interval, or change after Cybex testing for the reconstructed knee displace ment, the contralateral knee displacement, or side-to- side difference. The average difference before and after Cybex testing was 0.1 mm for the reconstructed knee. In conclusion, a single Cybex test, performed at least 6 months after surgery, did not affect anterior tibial displacement in this study sample.
Anterior Cruciate Ligament Allograft Reconstruction in the Skeletally Immature Athlete
Authors: Andrews Michelle , Noyes Frank R. , Barber-Westin Sue D.
Published: June 2007

The purpose of this study was to evaluate anterior cru ciate ligament allograft reconstruction in skeletally im mature athletes. Eight patients (mean age, 13 years, 6 months; range, 10 to 15 years) with radiographic docu mentation of open growth plates had anterior cruciate ligament repair and reconstruction with fascia lata or Achilles tendon allograft tissue. A 7-mm graft was cen trally placed across the tibial physes and in an over- the-top position on the femur. All patients returned for followup a mean of 58 months (range, 22 to 94) post operatively. All had an immediate knee motion and re habilitation exercise program. The results were rated on a comprehensive rating system that assessed 20 vari ables. At followup, all patients showed closure of the growth plates. The difference in lower limb length, measured on scanograms, was not clinically significant. On KT-1000 arthrometer testing, 5 patients had less than 3 mm of increased anterior-posterior displacement (normal knee minus reconstructed knee) and 3 patients had between 3 and 5 mm. The final overall ratings were 6 excellent, 1 good, and 1 fair. The procedure is infre quently used, but appears to have merit in select, skel etally immature athletes who desire not to modify ath letic activity or when associated meniscal repairs warrant consideration for reconstruction.
Cervical Spinal Stenosis and Stingers in Collegiate Football Players
Authors: Meyer Scott A. , Schulte Kary R. , Callaghan John J. , Albright John P. , Powell John W. , Crowley Edward T. , El-Khoury Georges Y.
Published: June 2007

We evaluated the relationship of cervical spinal stenosis with the occurrence of "stingers" in collegiate football players who participated at our institution from 1987 through 1991. Preparticipation cervical spine radio graphs of 266 players were used to measure Torg ratio. Forty players with stingers were identified: 34 had an extension-compression mechanism; 6 had a brachial plexus stretch mechanism. Time-loss neck injuries oc curred in 31 players; the remaining 195 players were asymptomatic. The mean Torg ratio was significantly smaller for the stinger group (P = 0.02). The Torg ratio was less than 0.8 at 1 or more levels in 47.5% of the stinger group, 32.3% of the time-loss neck pain group, and 25.1 % of the asymptomatic group. No player with a brachial plexus stretch mechanism had a mean Torg ratio less than 0.8, but 20.6% of the players with an extension-compression mechanism had a mean Torg ratio less than 0.8. Players with a Torg ratio less than 0.8 had 3 times the risk of incurring stingers. We con clude that cervical spinal stenosis increases the risk for having stingers with complicated clinical courses.