bluuebunny/crossref_metadata_2025 huggingface dataset:
Posterior Cruciate Ligament Reconstruction
Authors: Galloway Marc T. , Grood Edward S. , Mehalik John N. , Levy Martin , Saddler Stephen C. , Noyes Frank R.
Published: June 2007

We studied posterior cruciate ligament reconstruction in a cadaveric model using two substitutes: a 1-mm diameter flexible cable and an 11-mm diameter Achil les tendon autograft. The thin cable allowed us to study five femoral and five tibial attachments in each knee. A nearly isometric attachment was located after cutting the posterior cruciate ligament while the tibia was re duced with a 100 N anterior force. The five femoral locations studied were the isometric location and four locations centered around this isometric point. The Achilles tendon reconstruction was used with both an isometric and a nonisometric femoral site, allowing us to confirm the results with the wire cable. Posterior motion limits were measured under a 100 N posterior force in the intact, posterior cruciate ligament-deficient, and posterior cruciate ligament-reconstructed knees. We found that the restoration of knee stability in flexion depended strongly on the femoral attachment location. A femoral attachment that was nonisometric by intra operative measurement, but within the posterior cruci ate ligament anatomic footprint, most closely repro duced the intact knee's posterior motion limits. Variations in the tibial attachment site produced only minor changes in the posterior motion limits. We con cluded that the proximal-distal location selected for the femoral attachment of a posterior cruciate ligament substitute was particularly important in the restoration of normal posterior motion limits.
The Effect of Protective Football Equipment on Alignment of the Injured Cervical Spine
Authors: Palumbo Mark A. , Hulstyn Michael J. , Fadale Paul D. , O'Brien Timothy , Shall Larry
Published: June 2007

No universally accepted management protocol is avail able for dealing with the protective equipment worn by a neck-injured football player. The purpose of this ca daveric study was to determine the effects of the hel met and shoulder pads on the alignment of 1) the intact lower cervical spine and 2) the partially destabilized C5-6 motion segment. In Group I cadavers ( N = 15), the lower cervical spine was tested in an intact condi tion. In Group II ( N = 8), the C5-6 motion segment was tested in both an intact and a partially destabilized condition. Each cadaver was placed supine on a back- board and four lateral cervical radiographs were ob tained as follows: no protective equipment, helmet only, helmet and shoulder pads, and shoulder pads only. Results for Group I showed that wearing both helmet and shoulder pads did not result in a significant change in cervical lordosis when compared with the neutral position (i.e., the no-equipment test). Cervical lordosis was significantly decreased in the helmet-only category (mean, 9.6°) and significantly increased in the shoulder pads-only category (mean, 13.6°). In Group II, destabilized specimens under the helmet test situa tion showed a significant mean increase in C5-6 for ward angulation (16.5°), posterior disk space height (3.8 mm), and dorsal element distraction (8.3 mm). Immobilizing the neck-injured football player with only the helmet or only the shoulder pads in place violates the principle of splinting the cervical spine in neutral alignment, according to our findings. We support the concept that removal of the helmet and shoulder pads should be an all-or-none proposition.
A Muscle-Splitting Approach to the Ulnar Collateral Ligament of the Elbow
Authors: Smith Garth R. , Altchek David W. , Pagnani Michael J. , Keeley John R.
Published: June 2007

The standard surgical approach for repair or recon struction of the ulnar collateral ligament of the elbow involves lifting off of the tendon of the common flexor bundle at its origin on the medial epicondyle. However, a more limited muscle-splitting approach may be fea sible. A muscle-splitting approach is less traumatic to the flexor-pronator muscle mass, and it could decrease operative time and lessen immediate morbidity after surgery. A proposed muscle-split through the common flexor bundle extends from the medial humeral epicon dyle to a point distal to the tubercle of the ulna such that repair or reconstruction can be performed on the ulnar collateral ligament. To examine the feasibility of this approach, we performed a study combining ana tomic dissections with clinical observations. We dis sected 15 fresh-frozen adult cadaveric elbows to ex amine the neuroanatomy of the medial side of the elbow. All pertinent nerves were identified and mapped. From these data, we defined a "safe zone" for a muscle-splitting approach to the ulnar collateral lig ament that allows adequate room for repair or recon struction of the ligament without risking denervation of the surrounding musculature. The safe zone extends from the medial humeral epicondyle to approximately 1 cm distal to the insertion of the ulnar collateral ligament on the tubercle of the ulna. Twenty-two patients with ulnar collateral ligament tears underwent either a direct repair or a reconstruction of the ligament using the proposed muscle-splitting approach. With a minimum followup of 1 year, there was no clinical evidence of muscle denervation. From the combined anatomic study and clinical data, we believe that a less traumatic muscle-splitting approach to the ulnar collateral liga ment affords a safe and simple surgical approach for repair or reconstruction of the ligament.
Validation of the Lift-Off Test and Analysis of Subscapularis Activity During Maximal Internal Rotation
Authors: Greis Patrick E. , Kuhn John E. , Schultheis Jeanne , Hintermeister Robert , Hawkins Richard
Published: June 2007

We used electromyographic analysis to determine the muscle activity of the shoulder muscles during the lift-off test and during resisted internal rotation. The activity in the upper and lower subscapularis muscle during a lift-off test from the region of the midlumbar spine was approximately 70% of maximal voluntary contraction. This level was significantly higher than for all the other muscles tested ( P < 0.05). The lift-off test with the hand placed in the region of the midlumbar spine resulted in one-third more electromyographic ac tivity in the subscapularis muscle than when the test was modified and performed with the hand at the but tocks region. A resisted lift-off test resulted in higher activities in all the muscles, but only a small increase in the pectoralis major muscle. The pectoralis major mus cle was significantly more active during resisted inter nal rotation with the arm in front of the body. Compar ison of activity in the upper subscapularis with that in the lower subscapularis muscle showed no significant differences during any of the tests. This study docu ments the importance of the subscapularis muscle dur ing the lift-off test and suggests that other potential internal rotators of the humerus have a limited role in maintaining internal rotation when the arm is placed behind the back.
The Effect of Nonablative Laser Energy on Joint Capsular Properties
Authors: Hayashi Kei , Thabit George , Vailas Arthur C. , Bogdanske John J. , Cooley A.J. , Markel Mark D.
Published: June 2007

The purpose of this study was to evaluate the effect of laser energy at nonablative levels on joint capsular histologic and biochemical properties in an in vitro rabbit model. The medial and lateral portions of the femoropatellar joint capsule from both stifles of 12 mature New Zealand White rabbits were used. Speci mens were divided into three treatment groups (5 watts, 10 watts, and 15 watts) and one control group using a randomized block design. Specimens were placed in a 37° bath of lactated Ringer's solution and laser energy was applied using a holmium:yttrium-alu minum-garnet laser in four transverse passes across the tissue at a velocity of 2 mm/sec with the handpiece set 1.5 mm from the synovial surface. Histologic anal ysis revealed thermal alteration of collagen (fusion) and fibroblasts (pyknosis) at all energy densities, with higher laser energy causing significantly greater mor phologic changes over a larger area ( P < 0.05). Ap plication of laser energy did not significantly alter the biochemical parameters evaluated, including type I col lagen content and nonreducible crosslinks ( P > 0.05). This study demonstrated that nonablative laser energy caused significant thermal damage to the joint capsular tissue in an energy-dependent fashion, but type I col lagen content and nonreducible crosslinks were not significantly altered.
Incidence of Injury in Texas Girls' High School Basketball
Authors: Gomez Eduardo , DeLee Jesse C. , Farney William C.
Published: June 2007

We studied the incidence of injury in girl's varsity bas ketball to characterize injury demographics in high school athletics. We defined a reportable injury as one that occurred during organized practice or competition, resulted in either missed practice or game time, re quired physician consultation, or involved the head or face. We prospectively evaluated the athletes on team rosters during the 1993 to 1994 season from 100 ran domly selected Class 4A and 5A Texas public high schools that employed full-time certified athletic train ers. The 890 student athletes from 80 schools ranged in age from 14 to 18 years. Four hundred thirty-six injuries were reported for a rate of 0.49 per athlete per season. Injury risk, calculated on the basis of exposure time, was 0.4% per hour per athlete. Although game time accounted for only 12.5% of exposure time, it represented one half of the total injuries. Sprains and strains (56%) were the most common injuries, followed by contusions (15%) and dental injuries (14%). Injuries to the ankle (31 %) and knee (19%) were by far the most common. There were 34 severe injuries defined as requiring surgery or hospitalization, for a rate of 0.038 per athlete per season. Knee injuries were by far the most likely to require surgeries, and ACL injuries accounted for 69% of the severe knee injuries.
A Prospective Evaluation of a New Physical Examination in Predicting Glenoid Labral Tears
Authors: Liu Stephen H. , Henry Mark H. , Nuccion Stephen L.
Published: June 2007

We studied 62 patients (40 men and 22 women) with an average age of 28 years over a 28-month period who presented with shoulder pain that was refractory to 3 months of conservative management. Patients with a prior glenohumeral dislocation or a rotator cuff tear were excluded. The "crank" test was performed with the arm elevated 160° in the scapular plane of the body, loaded axially along the humerus, and with max imal internal and external rotation. Although similar tests have been described, the crank test is a new examination previously unreported. Half of the patients (31) had a positive crank test. Arthroscopy performed on all 62 patients revealed glenoid labral tears in 32 patients. Two patients who had positive crank tests did not have labral tears but had partial-thickness, articu lar-side rotator cuff tears. The sensitivity of the crank test was 91%, the specificity was 93%, the positive predictive value was 94%, and the negative predictive value was 90%. With these data, the crank test fulfills the criteria as a single physical examination test that is highly accurate for the preoperative diagnosis of gle noid labral tears. Accordingly, expensive imaging mo dalities currently used in this patient population may be employed less in the future.
The Posterolateral Aspect of the Knee
Authors: Terry Glenn C. , LaPrade Robert F.
Published: June 2007

Thirty cadaveric knees were dissected to obtain a de tailed understanding of the anatomic structures of the posterolateral aspect of the knee, and a dependable surgical approach to evaluate injuries to these struc tures was developed and used on 71 consecutive pa tients who were operated on for posterolateral knee injuries. Three fascial incisions and one lateral midcap sular incision were used to provide surgical access. The following individual anatomic structures were iden tified : the layers of the iliotibial tract, long and short heads of the biceps femoris muscle, fibular collateral ligament, midthird lateral capsular ligament, fabello fibular ligament, posterior arcuate ligament, popliteus muscle complex, lateral coronary ligament, and poste rior capsule. This study increased our understanding of the individual anatomic structures and the relationships between these components. The surgical approach provided for the evaluation of these anatomic struc tures should aid the surgeon in properly assessing the injuries before surgical repair. This information should also stimulate more anatomic, biomechanical, and clin ical studies of the posterolateral aspect of the knee.
The Effect of Intercondylar Notchplasty on the Patellofemoral Articulation
Authors: Morgan Eric A. , McElroy J. Jeffrey , DesJardins John D. , Anderson Donald D. , Steensen Robert N.
Published: June 2007

Using pressure-sensitive film, we measured the patel lofemoral contact areas and pressures after increasing degrees of notchplasty in eight fresh-frozen cadaveric knee specimens. Each specimen was stabilized on an axial loading frame with physiologic loads applied through the quadriceps tendon at varying flexion an gles. The patellofemoral joint was loaded at 90°, 105°, and 120° of knee flexion. The same measurements were then obtained after serial notchplasties of 3, 6, and 9 mm. The film was analyzed for contact areas and for contact pressures by densitometry. There was no statistical significance between contact area or pres sure after notchplasties of 3, 6, or 9 mm at 90°, 105°, and 120° of knee flexion. These data suggest that routine notchplasty does not affect the patellofemoral articulation.
Classification and Management of Arthrofibrosis of the Knee after Anterior Cruciate Ligament Reconstruction
Authors: Shelbourne K. Donald , Patel Dipak V. , Martini Douglas J.
Published: June 2007

We report 72 patients with disabling knee arthrofibrosis who were treated at our clinic. All patients had painful restriction of extension or limitation of both extension and flexion that had persisted despite physical therapy. The level of arthrofibrosis was categorized into one of four types: Type 1 (25 patients), <10° extension loss and normal flexion; Type 2 (16 patients), >10° exten sion loss and normal flexion; Type 3 (15 patients), >10° extension loss and >25° flexion loss with a tight patella; and Type 4 (16 patients), >10° extension loss, 30° or more flexion loss, and patella infera with marked patellar tightness. All patients were treated with outpa tient arthroscopic surgery. Anterior scar resection down to the proximal tibia was required for all patients with Types 2, 3, and 4 arthrofibrosis. Notchplasty was performed when necessary. Medial and lateral capsu lar releases and knee manipulation were required for patients with Type 3 or 4 arthrofibrosis. Postopera tively, all patients with Types 2, 3, and 4 arthrofibrosis were treated with outpatient serial extension casting. At the time of latest followup (28 to 115 months), the mean improvement of range of motion was as follows: Type 1, 7° of extension; Type 2, 14° of extension; Type 3, 13° of extension and 28° of flexion; and Type 4, 18° of extension and 27° of flexion. Improvement was also found for the mean stiffness, self-evaluation, functional activity, and Noyes knee scores in all groups.
The Diagnosis of Meniscal Tears in Ath letes
Authors: Muellner Thomas , Weinstabl Reinhard , Schabus Rudolf , Vecsei Vilmos , Kainberger Franz
Published: June 2007

This study evaluated the predictability of clinical exam ination alone in comparison with magnetic resonance imaging in the diagnosis of meniscal tears in compet itive athletes. Ninety-three competitive athletes were prospectively investigated between 1992 and 1995. A total of 57 athletes were operated on based on clinical examination alone, and the 36 remaining athletes had magnetic resonance imaging before surgery. The cor rect diagnosis of a meniscal lesion was made on clin ical examination alone in 83 athletes (89%) and on magnetic resonance imaging the correct diagnosis was also made in 89% of 36 athletes. The overall values for the clinical investigation of the medial and lateral me nisci combined were 94.5%, 91.5%, 99%, 96.5%, 87% for accuracy, positive predictive value, negative predic tive value, sensitivity, and specificity, respectively. The overall values for magnetic resonance imaging of the medial and lateral menisci combined were 95.5%, 96.5%, 91.5%, 98%, 85.5% for accuracy, positive pre dictive value, negative predictive value, sensitivity, and specificity, respectively.
Traumatic Tears of the Subscapularis Tendon
Authors: Deutsch Allen , Altchek David W. , Veltri Daniel M. , Potter Hollis G. , Warren Russell F.
Published: June 2007

The study population consisted of 14 shoulders in 13 consecutive patients with surgically confirmed isolated subscapularis tendon tears. In all but three patients, the mechanism of injury was traumatic hyperextension or external rotation of the abducted arm. All patients reported pain and weakness in the affected shoulder. Physical findings revealed limited passive range of motion at maximal internal and external rotation due to pain, weakness of internal rotation of the shoulder, and tenderness in the region of the intertubercular groove. However, these findings did not conclusively point to the subscapularis tendon as the site of injury. Preop erative interpretation of magnetic resonance imaging studies was used to diagnose tears of the subscapu laris tendon in 14 shoulders and biceps tendon sublux ation or dislocation in 6 shoulders. On arthroscopic examination, one patient was found to have a partial- thickness tear that was treated with arthroscopic de bridement. Six shoulders had full-thickness tears of the subscapularis tendon, and seven shoulders had full- thickness tears associated with concomitant biceps tendon pathologic conditions, including subluxation, dislocation, or rupture. The full-thickness subscapu laris tendon tears were repaired via an open anterior approach to the shoulder through the deltopectoral groove. Associated biceps tendon injuries were treated with tenodesis of the tendon to the intertubercular groove. Our early followup results have shown that, with proper diagnoses and surgical treatments, pa tients have greatly decreased pain and marked im provement in shoulder function.
Central Quadriceps Tendon for Anterior Cruciate Ligament Reconstruction
Authors: Harris N. Lindsay , Smith David A. B. , Lamoreaux Lisa , Purnell Mark
Published: June 2007

We examined the anatomic and biomechanical adequacy of the central quadriceps tendon as an al ternative graft source for anterior cruciate ligament reconstruction. Morphometry was performed on 15 preserved and 6 fresh-frozen specimens. Biomechani cal testing was performed on the six fresh-frozen spec imens. We initially used a triple suture through the tendon construction, and then clamping directly on the tendon. Morphometry yielded the following meas urements: length, 6.1 ± 1.0 cm; width, 2.7 cm (range, 2.1 to 3.7); and thickness, 7 mm (range, 6.4 to 7.8). The thickness was 1.8 times that of the patellar tendon. Biomechanical testing showed that suture failure oc curred at 692 ± 181 N, and tendon failure occurred at 1075 ± 449 N. The load to tendon failure was 1.36 times that of a comparable-width patellar tendon graft, although the difference was not statistically significant. The failure mode was primarily through partial or com plete tendinous avulsion, with only one specimen fail ing at midsubstance. These findings show the central quadriceps graft is of sufficient size and strength to be used for anterior cruciate ligament reconstruction.
Quantitative Analysis of Synovial Fibrosis in the Infrapatellar Fat Pad Before and After Anterior Cruciate Ligament Reconstruction
Authors: Murakami Shunichi , Muneta Takeshi , Ezura Yoichi , Furuya Kohtaro , Yamamoto Haruyasu
Published: June 2007

We performed quantitative analysis of synovial fibrosis in the infrapatellar fat pad in 26 patients who under went arthroscopically assisted anterior cruciate liga ment reconstructions. Twelve patients underwent re construction with patellar tendon autografts, and 14 had reconstructions with semitendinosus and gracilis tendon autografts. Synovial samples were obtained at the time of reconstruction from 10 patients and at second-look arthroscopy from all 26 patients. Sections from quick-frozen samples were stained with either hematoxylin and eosin or Fast green and Sirius red. We used sodium hydroxide in absolute methanol to elute the Fast green and Sirius red stains, and the total collagen content of each section was estimated by measuring the optical density of the eluted solution. The volume of each section was determined on a computer using an imaging program, and collagen content per unit of tissue was calculated. Median col lagen content was 15.3 μg/mm3 for the preoperative samples, 25.1 μg/mm3 for the group with patellar ten don autografts, and 27.1 μg/mm 3 for the group with hamstring tendons autografts. Analysis of preoperative and postoperative paired samples revealed a signifi cant increase in synovial collagen after anterior cruci ate ligament reconstruction. We observed increased fibrosis in patients who had pain on exertion or stiff ness in squatting after the reconstructive surgery.
An Eccentric- and Concentric-Strength Profile of Shoulder External and internal Rotator Muscles in Professional Baseball Pitchers
Authors: Sirota Stephen C. , Malanga Gerard A. , Eischen Joseph J. , Laskowski Edward R.
Published: June 2007

The purpose of this study was to establish a data base on the isokinetic eccentric muscular performance char acteristics of external and internal rotator muscles in the shoulders of professional baseball pitchers. Con centric data are also included and compared with pre viously published concentric studies. Twenty-five pro fessional baseball pitchers were evaluated with a Kin- Com isokinetic dynamometer. The subjects tested had a mean age of 23.5 years and a mean body weight of 199 pounds. Eccentric and concentric isokinetic tests were performed at 60 and 120 deg/sec. The testing protocol was standardized for each subject. Test re sults indicated no statistically significant difference in mean torque between throwing and nonthrowing shoulders for either external or internal rotator muscle groups. Eccentric strength was significantly greater than concentric strength for all muscle groups tested. The external-to-internal rotator muscle strength ratios were well above those previously published for high school through professional pitchers. Mean torque-to- lean body weight ratios were also included to establish a data base. This study establishes one of the first data bases for eccentric isokinetic muscle strength of shoul der rotator muscles in professional baseball pitchers. The data may help clinicians prevent and rehabilitate shoulder injuries in professional throwing athletes.
Intercondylar Notch Width and Its Relation to the Configuration and Cross-Sectional Area of the Anterior Cruciate Ligament
Authors: Muneta Takeshi , Takakuda Kazuo , Yamamoto Haruyasu
Published: June 2007

If a narrow intercondylar notch contains a smaller an terior cruciate ligament, that may explain why people with narrow notches have a higher incidence of ante rior cruciate ligament injuries. To investigate the signif icance of notch width measurement, we used 16 em balmed cadaveric knees. A positive mold of the entire anterior cruciate ligament, including its femoral and tibial insertions, was created with silicone rubber and plaster commonly used for dental molding. We had two hypotheses to test from this study. One was that the dimensions of the anterior cruciate ligament can be predicted by the notch width. The other was that the size of a person's anterior cruciate ligament can be predicted by a caliper measurement of the intercondy lar notch. The width, sagittal length, and cross-sec tional area of the midsubstance and the femoral and tibial insertions of the anterior cruciate ligament were measured. The notch width index, the ratio of notch width to width of the femoral condyle, showed a posi tive correlation only to the ratio of width to sagittal length of the tibial insertion. None of the parameters showed any differences between the knees with a notch width index less than or equal to 0.2 and those with a notch width index greater than 0.2. The knees with small notch width indexes did not have thinner anterior cruciate ligaments in them. These findings may not be applicable to knees obtained from other races, i.e., not Japanese.
Preseason Hamstring Muscle Weakness Associated with Hamstring Muscle Injury in Australian Footballers
Authors: Orchard John , Marsden John , Lord Stephen , Garlick David
Published: June 2007

Hamstring muscle strain is the most prevalent injury in Australian Rules Football, accounting for 16% of play ing time missed as a result of injury. Thirty-seven pro fessional footballers from an Australian Football League team had preseason measurements of ham string and quadriceps muscle concentric peak torque at 60, 180, and 300 deg/sec measured on a Cybex 340 dynamometer. Players were studied prospectively throughout the 1995 season. During that time, six play ers sustained clinically diagnosed hamstring muscle injuries that caused them to miss match-playing time. The injured hamstring muscles were all weaker than in the opposite leg in absolute values and hamstring-to- quadriceps muscle ratios. According to our t-test re sults, hamstring muscle injury was significantly asso ciated with a low hamstring-to-quadriceps muscle peak torque ratio at 60 deg/sec on the injured side and a low hamstring muscle side-to-side peak torque ratio at 60 deg/sec. Flexibility (as measured by the sit-and-reach test) did not correlate with injury. Discriminant-function analysis using the two significant ratio variables re sulted in a canonical correlation with injury of 0.4594 and correctly classified legs into injury groups with 77.4% success. These results indicate that preseason isokinetic testing of professional Australian Rules foot ballers can identify players at risk of developing ham string muscle strains.
The Effect of Thermal Heating on the Length and Histologic Properties of the Glenohumeral Joint Capsule
Authors: Hayashi Kei , Thabit George , Massa Kathleen L. , Bogdanske John J. , Cooley A.J. , Orwin John F. , Markel Mark D.
Published: June 2007

The purpose of this study was to evaluate the effect of temperature on shrinkage and the histologic properties of gienohumeral joint capsular tissue. Six fresh-frozen cadaveric shoulders were used for this study. Seven joint capsule specimens were taken from different re gions from each glenohumeral joint and assigned to one of seven treatment groups (37°, 55°, 60°, 65°, 70°, 75°, 80°C) using a randomized block design. Speci mens were placed in a tissue bath heated to one of the designated temperatures for 10 minutes. Specimens treated with temperatures at or above 65°C experi enced significant shrinkage compared with those treated with a 37°C bath. The posttreatment lengths in the 70°, 75°, and 80°C groups were significantly less than the pretreatment lengths. Histologic analysis re vealed significant thermal alteration characterized by hyalinization of collagen in the 65°, 70°, 75°, and 80°C groups. This study demonstrated that temperatures at or above 65°C caused significant shrinkage of gleno humeral joint capsular tissue. These results are con sistent with histologic findings, which revealed signifi cant thermal changes of collagen in the 65°, 70°, 75°, and 80°C groups. To verify the validity of laser appli cation for shrinkage of joint capsule, studies designed to compare these findings with the effects of laser energy must be performed.
The Role of Proprioception in the Management and Rehabilitation of Athletic Injuries
Authors: Lephart Scott M. , Pincivero Danny M. , Giraido Jorge L. , Fu Freddie H.
Published: June 2007

Rehabilitation continues to evolve with the increased emphasis on patient management and proprioceptive training. Proprioception can be defined as a special ized variation of the sensory modality of touch that encompasses the sensation of joint movement (kines thesia) and joint position (joint position sense). Numer ous investigators have observed that afferent feedback to the brain and spinal pathways is mediated by skin, articular, and muscle mechanoreceptors. Examining the effects of ligamentous injury, surgical intervention, and proprioceptiveiy mediated activities in the rehabil itation program provides an understanding of the com plexity of this system responsible for motor control. It appears that this neuromuscular feedback mechanism becomes interrupted with injury and abnormalities, and approaches restoration after surgical intervention and rehabilitation. Rehabilitation programs should be de signed to include a proprioceptive component that ad dresses the following three levels of motor control: spinal reflexes, cognitive programming, and brainstem activity. Such a program is highly recommended to promote dynamic joint and functional stability. Thus far, current knowledge regarding the basic science and clinical application of proprioception has led the pro fession of sports medicine one step closer to its ulti mate goal of restoring function.
The Relationship Between Passive Joint Laxity and Functional Outcome After Anterior Cruciate Ligament Injury
Authors: Snyder-Mackler Lynn , Fitzgerald G. Kelley , Bartolozzi Arthur R. , Ciccotti Michael G.
Published: June 2007

Twenty patients with anterior cruciate ligament-defi cient knees were studied. Ten patients returned to all sports activities (compensators) and 10 patients were not improved with nonoperative management and re quired surgical stabilization (noncompensators). Joint laxity was measured using a KT-2000 arthrometer (manual maximum Lachman). Subjects completed a Lysholm questionnaire and Knee Outcome Score. The International Knee Documentation Committee form was also completed. Patients also rated their knee function on a scale of 1 to 100. There was no difference in level and frequency of athletic activity between the two groups before their anterior cruciate ligament inju ries as determined by the knee outcome score. The compensator group had a mean side-to-side difference of 3.25 mm at 89 N and the noncompensators had a mean difference of 3 mm preoperatively. Manual max imum tests gave side-to-side differences of 6.7 mm for the compensators and 6 mm for the noncompensators. There were no differences in laxity measures between groups. The correlation between knee outcome scores and side-to-side laxity measurements were not signif icant. Measurements of anterior laxity in anterior cru ciate ligament-deficient patients were not correlated with measures of functional outcome used in this study. Functional outcome measurements that are par tially based on joint laxity measures, such as the Inter national Knee Documentation Committee form, may artificially overestimate the disability after anterior cru ciate ligament rupture.
Biomechanical Analysis of the Effectiveness of In-Line Skating Wrist Guards for Preventing Wrist Fractures
Authors: Giacobetti Frank B. , Sharkey Peter F. , Bos-Giacobetti Mary A. , Hume Eric L. , Taras John S.
Published: June 2007

The purpose of this investigation was to determine the effectiveness of commercially available wrist guards in preventing wrist fractures. Forty arms were harvested from 20 cadaveric specimens. The forearms from each cadaver, one with a wrist guard and one without a wrist guard, were then fractured using an Instron Servohy draulic Material Testing System. The group of forearms tested to failure without wrist guards failed at an aver age force of 2245 N, while the group tested with wrist guards fractured at an average force of 2285 N, reveal ing no statistical difference. Similarly, observed frac ture patterns were not noted to be different in the two groups. The in-line skating wrist guards tested were not effective in preventing wrist fractures under the experimental conditions of our study.
Clinical Findings in Competitive Swimmers with Shoulder Pain
Authors: Bak Klaus , Faunø Peter
Published: June 2007

We clinically evaluated 36 competitive swimmers who had shoulder pain; the majority were women. Twenty- three swimmers had unilateral shoulder pain and 13 had bilateral pain, making a total of 49 painful shoul ders. Shoulder pain had been present significantly longer in swimmers with bilateral shoulder pain (mean, 104 weeks) than in swimmers with unilateral pain (mean, 33 weeks). Twelve shoulders exhibited signs of impingement without excessive humeral head transla tion. In 25 shoulders, concomitant signs of impinge ment and increased glenohumeral translation, together with a positive apprehension sign, were found. Four swimmers, who were generally joint hypermobile, ex hibited bilateral impingement signs and excessive hu meral head translation, most commonly in the antero inferior direction. Four shoulders had excessive humeral head translation and apprehension without impingement. Lack of coordination in the scapulo humeral joint was seen significantly more often in symptomatic than in asymptomatic shoulders. Hawkins' test for impingement was more sensitive than Neer's test. Swimmers with shoulder pain have vari able clinical findings. The majority demonstrate signs of impingement and increased humeral head transla tion in the anteroinferior direction together with a pos itive apprehension sign. This nontraumatic instability might result from wearing of the anteroinferior capsu loligamentous complex. The different clinical findings might represent different stages of the same condition.
Septic Arthritis After Arthroscopic Anterior Cruciate Ligament Reconstruction
Authors: Williams Riley J. , Laurencin Cato T. , Warren Russell F. , Speciale Alessandro C. , Brause Barry D. , O'Brien Stephen
Published: June 2007

We performed a retrospective study of knee joint in fections after arthroscopic anterior cruciate ligament reconstruction at our institution. Two thousand five hundred anterior cruciate ligament reconstructions were performed between 1988 and 1993. Seven (0.3%) patients experienced postoperative deep infec tions of the knee. All anterior cruciate ligament recon structions were performed using arthroscopically as sisted techniques. Six (86%) of these patients had concomitant open procedures performed, including meniscal repair, posterolateral corner reconstruction, and medial collateral ligament reconstruction. Four pa tients had acute (<2 weeks), two patients had sub- acute (2 weeks to 2 months), and one patient had late (>2 months) infections. All patients had positive cul tures from knee joint aspirates with the organisms Staphylococcus aureus, Staphylococcus epidermidis, Peptostreptococcus, or a combination thereof. All pa tients underwent immediate arthroscopic irrigation and debridement. All infections were intraarticular; six pa tients also had extraarticular sites of infection. Four patients underwent repeat irrigation and debridement at approximately 1 week. The anterior cruciate liga ment graft was removed from four patients. All patients were treated with intravenous antibiotics for 4 to 6 weeks, protected weightbearing, and physical therapy. At a mean followup of 29 months, mean knee exten sion was 0°, and mean knee flexion was 122° (range, 70° to 135°). Six (86%) patients had minimal to no pain in their operative knee, and they were satisfied with their functional results.
The Effect of Lifelong Exercise on Canine Articular Cartilage
Authors: Newton Peter M. , Mow Van C. , Gardner Thomas R. , Buckwalter Joseph A. , Albright John P.
Published: June 2007

The effect of long-term exercise on canine knees was studied to determine whether an increased level of lifelong weightbearing exercise causes degeneration, or changes that may lead to degeneration, of articular cartilage. Eleven dogs were exercised on a treadmill at 3 km/hr for 75 minutes 5 days a week for 527 weeks while carrying jackets weighing 130% of their body weight. Ten control dogs were allowed unrestricted activity in cages for the 550 weeks. At the completion of the study all knee joints were inspected for evidence of joint injury and degeneration. Articular cartilage sur faces from the medial tibial plateau were examined by light microscopy, the cartilage thickness was meas ured, and the intrinsic material properties were deter mined by mechanical testing. No joints had ligament or meniscal injuries, cartilage erosions, or osteophytes. Light microscopy did not demonstrate cartilage fibrilla tion or differences in safranin O staining of the tibial articular cartilages between the two groups. Further more, the tibial articular cartilage thickness and me chanical properties did not differ between the two groups. These results show that a lifetime of regular weightbearing exercise in dogs with normal joints did not cause alterations in the structure and mechanical properties of articular cartilage that might lead to joint degeneration.
Long-term Results of Anterior Cruciate Ligament Reconstruction with a Dacron Prosthesis
Authors: Maletius Wolfgang , Gillquist Jan
Published: June 2007

In this prospective study we investigated 70 patients with chronic anterior instability who underwent anterior cruciate ligament reconstruction with a Dacron pros thesis. Fifty-five (79%) patients could be followed up at a mean of 9 years. Within the follow-up time, 44% (29 of 66) of the prostheses were diagnosed as ruptured; the annual rupture frequency was 5%. Second recon structions were performed for 20 patients (29%), 5 patients had third reconstructions, and 9 patients wanted no further surgical treatment. Fifty-two patients (74% of the original group) underwent radiographic examination. Eighty-three percent (43) of these pa tients had radiographic changes in the operated knee, and 40% (21 of 52) had joint space reduction up to 50%. The rate of radiographically detected osteoarthi tis was increased 10 times compared with the normal knee. Patients with medial instability and patients older than 30 years at the initial operation had more severe osteoarthritic changes. Based on the functional results of the patients with a ligament in place after 9 years, only 14% (10) of the original group had acceptable stability and knee function.
Arthroscopic Capsular Release for the Stiff Shoulder
Authors: Zanotti Robert M. , Kuhn John E.
Published: June 2007

The anatomic proximity of several neurovascular structures remains a major concern to the surgeon interested in performing arthroscopic capsular re lease. We evaluated the anatomic relationships be tween the released capsule and the axillary nerve, posterior circumflex humeral artery, and brachial ar tery in a frozen cadaveric model. With the aid of electrocautery, seven cadaveric shoulders under went complete arthroscopic capsular release. The release was performed circumferentially, approxi mately 1 cm lateral to the glenoid rim. All shoulders were subsequently frozen and sectioned through the plane of the capsular release while the shoulder was maintained in the lateral arthroscopic position (45° of abduction and 20° of flexion). Anatomic dissection revealed an average distance from the capsular re lease to the axillary nerve of 7.04 mm (95% confi dence interval, 5.62, 8.47), to the posterior circum flex humeral artery of 8.2 mm (95% confidence interval, 6.41, 9.99), and to the brachial artery of 15.97 mm (95% confidence interval, 9.85, 22.09). As the axillary nerve was followed medially from the released capsule, the inferior border of the subscap ularis muscle became interposed between the cap sule and the axillary nerve. This limited anatomic study shows that a relatively safe margin between the capsule and the neighboring neurovascular structures can be obtained by releasing the capsule within 1 cm of the glenoid rim.
Treatment of Plantar Fasciitis by lontophoresis of 0.4% Dexamethasone
Authors: Gudeman Scott D. , Eisele Sandra A. , Heidt Robert S. , Colosimo Angelo J. , Stroupe Amanda L.
Published: June 2007

Plantar fasciitis is a common problem in running sports. This study was undertaken to determine whether iontophoresis of dexamethasone in conjunc tion with other traditional modalities provides more im mediate pain relief than traditional modalities alone. Forty affected feet were randomly assigned to one of two groups. Group I feet were treated with traditional modalities and placebo iontophoresis. Group II feet received the traditional modalities plus iontophoresis of dexamethasone. Both groups were treated six times over 2 weeks. The subjects' clinical course was as sessed using the Maryland Foot Score. At the conclu sion of treatment, Group II patients had significantly greater improvement than Group I patients (increase on Maryland Foot Score of 6.8 ± 5.6 for Group II and 3.1 ± 4.1 for Group I). However, at followup 1 month after completion of treatment there was no significant difference between groups (increase of 5.6 ± 8.0 for Group I and 7.4 ± 6.3 for Group II). These results suggest that although traditional modalities alone are ultimately effective, iontophoresis in conjunction with traditional modalities provides immediate reduction in symptoms. Based on these results, iontophoresis of dexamethasone for plantar fasciitis should be consid ered when more immediate results are needed (i.e., performance athletes and active patients).
The Effects of Joint Position and Direction of Joint Motion on Proprioceptive Sensibility in Anterior Cruciate Ligament-Deficient Athletes
Authors: Borsa Paul A. , Lephart Scott M. , Irrgang James J. , Safran Marc R. , Fu Freddie H.
Published: June 2007

We studied a group of anterior cruciate ligament-defi cient athletes to identify whether joint position and direction of joint motion have a significant effect on proprioception. Twenty-nine anterior cruciate ligament- deficient athletes were tested for their threshold to detect passive motion at both 15° and 45° moving into the directions of both flexion and extension. The single- legged hop test was used to identify function in the deficient limb. Results demonstrated statistically signif icant deficits in threshold to detect passive motion for the deficient limb at 15° moving into extension. For the deficient limb, threshold to detect passive motion was significantly more sensitive moving into extension than flexion at a starting angle of 15°; at a starting angle of 15° moving into extension threshold was significantly more sensitive than at a starting angle of 45° moving into extension. We conclude that in deficient limbs proprioception is significantly more sensitive in the end ranges of knee extension (15°) and is significantly more sensitive moving into the direction of extension. To effectively restore reflex stabilization of the lower limb we recommend a rehabilitation program empha sizing performance-based, weightbearing, closed ki netic chain exercise for the muscle groups that act on the knee joint.
Isometry Measurements in the Knee With the Anterior Cruciate Ligament Intact, Sectioned, and Reconstructed
Authors: Furia John P. , Lintner David M. , Saiz Paul , Kohl Harold W. , Noble Phillip
Published: June 2007

When assessing isometry during anterior cruciate lig ament surgery, it is assumed that points determined to be isometric remain so after reconstruction. We sought to evaluate if isometric measurements vary with the status of the anterior cruciate ligament. A computer ized electronic isometer was used to measure the magnitude and pattern of change in separation dis tance between a constant point in the tibial insertion of the anterior cruciate ligament and five positions within the femoral insertion with the anterior cruciate ligament intact, sectioned, and reconstructed. For the center position, the magnitude and pattern of the change in separation distance was physiologically isometric in all conditions (maximal length change, 3.0 mm). For the posterior position, the isometry pattern remained phys iologic in each condition, and the magnitude of the separation distance was nearly isometric in all condi tions (maximal length change, 3.7 mm). The superior and inferior positions had similar isometric meas urements in the intact and sectioned conditions but significantly different measurements after anterior cru ciate ligament reconstruction. Intraoperative assess ment of isometry at positions in the center or posterior portion of the anterior cruciate ligament's femoral in sertion provides useful information that is not altered by reconstruction. For superior and inferior positions, however, points found to be isometric in the anterior cruciate ligament-deficient knee did not remain isomet ric after reconstruction.
Injuries to the Posterolateral Aspect of the Knee
Authors: LaPrade Robert F. , Terry Glenn C.
Published: June 2007

Seventy-one consecutive patients with posterolateral knee injuries had clinical stability testing abnormalities documented prospectively. We compared these find ings with the incidence and patterns of their injuries documented at surgery. An abnormal reverse pivot shift test was associated with injury to the fibular col lateral ligament (P = 0.01), popliteal components (P = 0.01), and midthird lateral capsular ligament (P = 0.02). An abnormal posterolateral external-rotation test at 30° of flexion was associated with injury to the fibular collateral ligament (P = 0.0001 ) and lateral gastrocne mius tendon (P = 0.01). An abnormal adduction test at 30° of flexion was associated with injury to the poste rior arcuate ligament (P = 0.02). The results of this study should alert the clinician to the possibility of injury to a specific anatomic structure when the correspond ing clinical stability test is abnormal. Because the fib ular collateral ligament was injured in only 23% of the knees in this large series of patients, we recommend that an injury to the fibular collateral ligament not be the sole determining factor in making the diagnosis of pos terolateral injuries. The wide array of injuries to many individual anatomic components that we found indi cates the complexity of injuries to the posterolateral aspect of the knee.
The Fibular Collateral Ligament-Biceps Femoris Bursa
Authors: LaPrade Robert F. , Hamilton Christopher D.
Published: June 2007

The anatomy of the fibular collateral ligament-biceps femoris bursa is described. The bursa is located lateral to the distal quarter of the fibular collateral ligament and forms an inverted "J" shape around the anterior and anteromedial portions of the ligament. Its most distal margin is just proximal to the fibular head where the fibular collateral ligament inserts, and its more proximal aspect is at the superior edge of the anterior arm of the long head of the biceps femoris muscle. We found this structure in all 50 knees dissected; there was a constant anatomic location of the fibular collat eral ligament-biceps femoris bursa in all specimens. Measurement of the anatomic dimensions of the bursa revealed a mean width of 8.4 mm and a mean height of 18 mm. Knowing the prevalence, shape, size, and anatomic location of this bursa may aid the clinician in the differential diagnosis of lateral knee pain.