bluuebunny/crossref_metadata_2025 huggingface dataset:
Biomechanics of the golf swing in players with pathologic conditions of the forearm, wrist, and hand
Authors: Cahalan Thomas D. , Cooney William P. , Tamai Kazuo , Chao Edmund Y.S.
Published: June 2007

Golf is an activity generally stressful to the hands and wrists and particularly can produce increasing symp toms in players with underlying problems such as hand and wrist arthritis or tendinitis. The purpose of this study was to quantitate wrist motion and club head/ ball impact force in subjects with pathologic conditions of the hand, wrist, or forearm, within a laboratory environment. A regular straight-handled golf club was compared to a new BioCurve handle design that has a 19° ulnar bend. We measured and compared the effect of the two grips on wrist motion, club head velocity, ball impact force, ball impact location, and isometric torsional strength in 20 subjects who had a variety of upper extremity disorders. This data was then com pared to data collected in an identical fashion from golfers without such conditions.

The results of our study show that there were no differences related to club handle design on impact force or impact location, club head velocity, or club head path and face angle. Wrist kinematic differences were minimal between handle designs. The differences that were significant (P < 0.05) centered around the decreased ulnar deviation of the left hand that resulted when subjects used the BioCurve handle design, which also allowed greater resistance to torque than the straight grip club. In addition to collecting objective data, we asked subjects for their opinions of the two grips. As a whole, the normal group and the group with pathologic conditions noted more comfort, improved grip, and less shock transmission with the BioCurve handle.
Syndesmotic ankle sprains
Authors: Boytim Mark J. , Fischer David A. , Neumann Larry
Published: June 2007

In this study we reviewed ankle sprains in a professional football team over a 6 year period. Fifteen players who sustained syndesmotic ankle sprains were compared with 28 players who sustained significant lateral ankle sprains. Players with syndesmotic sprains missed sig nificantly more games and practices and they received substantially more treatments than players with lateral ankle sprains. Physical examination findings, results of radiographic evaluations, and etiologic factors are dis cussed. The external rotation stress test, a clinical method for diagnosis of this type of sprain at the time of injury, is described.

Results of this study clearly demonstrate a prolonged recovery time for syndesmotic ankle sprains. Physi cians and trainers who are aware of this injury can differentially diagnose these two types of sprains in the early postinjury period by the method described.
Fatigue fracture of the ulna occurring in pitchers of fast-pitch softball
Authors: Tanabe Shingo , Nakahira Jun , Bando Eizo , Yamaguchi Hisao , Miyamoto Hiroshi , Yamamoto Akira
Published: June 2007

We have reported three cases of fatigue fracture of the ulna in male pitchers of fast-pitch softball. To elucidate the etiology of injury, we first selected three healthy male and three healthy female pitchers from a well- trained college team and analyzed their forearm move ment by high-speed cinematography. This showed slight flexion of the elbow joints during wind-up motion, dorsal flexion of the hand joints upon releasing the ball, and extreme pronation of the forearms during the fol low-through. We then took 8 mm CT scanning sections of the forearms. Using these images, we investigated shapes and areas of cross-sections of the ulna and its cortical and cancellous bones from the elbow to the hand joints. Our results reveal that the shapes of the sections are significantly different from circles at around the center of the ulna, and the cross-sectional areas are smaller in the middle one-third of the ulna than in other parts. These observations imply that fatigue frac tures of the ulna in pitchers of fast-pitch softball must be torsionally induced, tending to occur at the middle one-third of the bone.
The O'Donoghue triad revisited
Authors: Shelbourne K. Donald , Nitz Paul A.
Published: June 2007

We identified 60 consecutive patients with combined anterior cruciate and medial collateral ligament (ACL- MCL) disruptions that were incurred during athletic endeavors. Each underwent acute reconstruction of the ACL. The arthroscopic data obtained at the time of reconstructive surgery was reviewed in order to deter mine the incidence of O'Donoghue's triad (the "unhappy triad"), consisting of ACL, MCL, and medial meniscus tears.

Patients were subdivided into two groups for analysis based upon the degree of MCL injury at time of pres entation (Group I, 35 patients with a second-degree sprain; Group II, 25 patients with a complete, or third- degree injury). Medial meniscus tears were an uncom mon finding. Lateral meniscus tears significantly out numbered medial meniscus tears in both groups, oc curring in 25 (71 %) of Group I patients and 8 (32%) of those in Group II. Even chondral fractures of the lateral femoral condyle outnumbered medial meniscus tears [6 (17%) versus 4 (11 %)] in patients with a second- degree MCL sprain. Furthermore, when present in Group I patients, tears of the medial meniscus were associated with a concomitant lateral meniscus injury. Group II patients were more likely (60%) than Group I not to have any meniscal abnormality at all.

We conclude that the classic O'Donoghue triad is, in fact, an unusual clinical entity among athletes with knee injuries; it might be more accurately described as a triad consisting of ACL, MCL, and lateral meniscus tears. This injury combination appears to be more common when an incomplete, or second-degree, tear of the medial collateral has occurred. Third-degree MCL injuries in conjunction with ACL disruptions seem to "protect" joint surfaces, as patients with these injuries most commonly demonstrate an absence of further intraarticular abnormality (meniscal or chondral).
Prospective evaluation of arthroscopically assisted anterior cruciate ligament reconstruction
Authors: Marder Richard A. , Raskind John R. , Carroll Michael
Published: June 2007

Eighty consecutive patients with chronic laxity due to a torn ACL underwent arthroscopically assisted recon struction with either autogenous patellar tendon or doubled semitendinosus and gracilis tendons. Recon structions were performed on a one-to-one alternating basis. Preoperatively, no significant differences be tween the two groups were noted with respect to age, sex, level of activity, and degree of laxity (chi square analysis). A standard rehabilitation regimen was used for all patients after surgery including immediate pas sive knee extension, early stationary cycling, protected weightbearing for 6 weeks, avoidance of resisted ter minal knee extension until 6 months, and return to activity at 10 to 12 months postoperatively.

Seventy-two patients were evaluated at a minimum of 24 months postoperatively (range, 24 to 40 months). No significant differences were noted between groups with respect to subjective complaints, functional level, or objective laxity evaluation, including KT-1000 meas urements. Seventeen of 72 patients (24%) experienced anterior knee pain after ACL reconstruction. Overall, 46 of 72 patients (64%) returned to their preinjury level of activity. Mean KT-1000 scores were 1.6 ± 1.4 mm for the patellar tendon group and 1.9 ± 1.3 mm for the semitendinosus and gracilis tendons group.

This study did find a statistically significant weakness in peak hamstrings torque at 60 deg/sec when recon struction was performed with double-looped semiten dinosus and gracilis tendons.
Healing of the medial collateral ligament in unstable rat knees
Authors: Lechner Christopher T. , Dahners Laurence E.
Published: June 2007

Immobilization has been shown to be detrimental to healing ligaments while early motion and exercise in crease healing ligament tensile strength. In order to take advantage of early motion and exercise without causing undesirable joint laxity in unstable rat knees we devised an internal joint restabilization procedure. The results in this well-established rat model were encouraging. Exercise in unstable rat knees caused increased medial collateral ligament laxity compared with a group allowed motion ad libitum. Joint laxity was significantly decreased in the restabilized groups and no adverse effects of exercise were noted. Tensile strength was increased in healing medial collateral lig aments of both exercise groups regardless of the sta bility of the joint. This study supports the use of early aggressive rehabilitation of injured joints considered stable and encourages the development of methods to provide secure dynamic internal or external stabilization of severely injured human joints.
The normal shoulder during freestyle swimming
Authors: Pink Marilyn , Perry Jacquelin , Browne Anthony , Scovazzo Mary Lynn , Kerrigan John
Published: June 2007

The shoulder in swimming is subjected to multiple factors that can lead to a high injury rate. To prevent injury, one must understand the biomechanics of swim ming. This paper describes the electromyographic and cinematographic findings of 12 shoulder muscles in competitive swimmers without shoulder pain. The re sults show the three heads of the deltoid and the supraspinatus functioning in synchrony to place the arm at hand entry and exit, the rhomboids and upper trapezius to position the scapula for the arm, the pec toralis major and latissimus dorsi to propel the body, the subscapularis and serratus anterior as muscles with constant muscle activity, the teres minor functioning with the pectoralis major, and the infraspinatus active only to externally rotate the arm at midrecovery. This information is important to design optimal preventative and rehabilitative exercise programs.
Pes anserinus and iliotibial band transfer for anterior cruciate insufficiency
Authors: Larsen Eilif , Blyme Peter , Hede Adam
Published: June 2007

Twenty-one patients with chronic anterior cruciate lig ament insufficiency were treated with a combined ilio tibial band (Ellison) and pes anserinus (Slocum-Larson) transfer procedure. Preoperatively, the most prominent instabilities were drawer laxity in 16 patients and anter omedial rotation in 5 patients. After a median of 34 months of followup, 15 patients were absolutely satis fied with the result, 2 were fairly satisfied, and 4 were not satisfied at all, including 2 patients who had been reoperated. All of the patients with unsatisfactory re sults had a pivot shift and a positive Slocum test. Intraarticular derangements had no influence on the results. At followup, 14 patients demonstrated an an teromedial rotatory instability, indicating that the lateral stabilization procedure acted better than the medial one. Only a few patients returned to their preinjury levels of sports activity. Compared with other extraar ticular procedures in the literature, the results were quite similar. The operative procedures used in this study cannot be recommended in cases with combined instabilities of the knee.
The effects of knee brace wear on perceptual and metabolic variables during horizontal treadmill running
Authors: Highgenboten Carl L. , Jackson Allen , Meske Neil , Smith Jimmy
Published: June 2007

Past research has indicated that runners who wear a Lenox Hill Derotation Brace during treadmill running at 6 mph have an approximate 5% increase in oxygen consumption compared to those who run without the brace. The present study expanded those findings by determining the metabolic and perceptual effects of wearing four commercially available braces while tread mill running at speeds of 6, 7, and 8 mph. The four braces used in this study were the Generation II Poli- Axial Knee Cage, the Orthotech Performer, the CTi Brace, and the Lenox Hill Derotation Brace. Results indicated that the braces caused increases (P < 0.008) in oxygen consumption, heart rate, and ventilation in the 3% to 8% range compared to running without the brace. Peripheral ratings of perceived exertion were also elevated (P < 0.001) between 9% and 13%. How ever, no significant differences were found between the braces. Analysis of covariance indicated the weight of the brace accounted for the increased oxygen con sumption during the treadmill runs. We concluded that the braces examined in this study will cause a consist ent increase in metabolic cost, which is related to the weight of the braces.
Reproducibility of the Knee Signature System
Authors: Riederman Robert , Wroble Randall R. , Grood Edward S. , VanGinkel Laura , Shaffer Brian L.
Published: June 2007

To assess trial-to-trial, installation-to-installation, and day-to-day effects of the Knee Signature System, we studied anterior/posterior translation measurements in six normal subjects. The protocol consisted of testing both knees on 6 days with three installations per day and three trials per installation. We recorded anterior, posterior, and total anterior/posterior translation at ±20 and ±40 pounds of force at 30° of flexion. Addi tionally, after measuring anterior/posterior translation during passive knee extension, active extension, and active extension with 15 pounds of weight at the ankle, we calculated the difference in anterior translation at 30° of flexion between each of these three conditions. We analyzed the size of the effects and computed 90% confidence limits using analysis of variance.

Means and 90% confidence limits for total anterior/ posterior translation measured at ±20 pounds of force were: right knee, 6.8 ± 2.3; left knee, 8.2 ± 2.0; and right/left difference, 1.5 ± 2.7 mm. Left knee translation means were significantly greater than right knee means in all tests. Day-to-day effects, while statistically signif icant for right and left knee measurements, showed no significant effects for right/left differences. Trial-to-trial and installation-to-installation effects were not signifi cant for any parameter. Right/left differences during knee extension testing were smaller than for the stress test, measuring 0.1 mm or less, but confidence limits were larger, being ±3.7 mm for active extension-pas sive knee extension, ±1.5 mm for 15 pounds of weight at the ankle-active extension, and ±4.6 mm for 15 pounds of weight at the ankle-passive knee extension. Active extension produced 6.3 mm more anterior trans lation at 30° of flexion than passive extension. Active
Anterior cruciate reconstruction using a Dacron ligament prosthesis
Authors: Richmond John C. , Manseau Christopher J. , Patz Robert , McConville Owen
Published: June 2007

A single-center prospective study is presented on 35 patients who underwent anterior cruciate ligament re construction using a Dacron ligament prosthesis. All of the reconstructions were performed by the same sur geon, using the same technique. All of the patients had a history of symptomatic chronic ACL insufficiency. The mean follow-up interval for all patients was 50 months. There was an overall failure rate of 37.1% (13 patients), based on the presence of at least one of the following criteria: the presence of a pivot shift; a 2+ or greater anterior drawer or Lachman; instrumented laxity of >3 mm side-to-side translation in 20° of flexion at 89 N; or by arthroscopic documentation. Six of these 13 patients were documented by arthroscopy and 7 were clinical failures.

There were 26 patients with only anterior cruciate ligament laxity, and 9 patients with multiple instabilities or failed previous ACL reconstruction ("salvage"). In the group with isolated anterior cruciate ligament insuffi ciency, the failure rate was 23% (6 patients). In the salvage group, the failure rate was 78% (7 patients). There was a significant improvement in patient perform ance with respect to clinical laxity, Lysholm scores, and Tegner activity levels at 2 years postoperatively. There has been a subsequent deterioration in the performance of these patients through time.
The surgical treatment of symptomatic nonunions of the proximal (metaphyseal) fifth metatarsal in athletes
Authors: Rettig Arthur C. , Shelbourne K. Donald , Wilckens John
Published: June 2007

Eight athletes developed symptomatic nonunions of the base of the proximal fifth metatarsal in the metaphyseal region. All of the athletes were initially treated conserv atively without success. We reviewed their case histo ries and outlined a simple, effective, low morbidity surgical management of these lesions. Two nonunions successfully healed with internal fixation with an intra medullary compression screw. Five additional non unions were shelled out through a lateral incision of the peroneus brevis without disturbing its insertion. An eighth nonunion fragment was large and articulated the cuboid; it was fixed successfully with an intramedullary compression screw to preserve lateral foot mechanics. There were no complications. All patients returned to full activities 2 to 4 months after surgery.
Meniscal regeneration with copolymeric collagen scaffolds
Authors: Stone Kevin R. , Rodkey William G. , Webber Richard , McKinney LuAn , Steadman J. Richard
Published: June 2007

We sought to create a regeneration template for the meniscal cartilage of the knee to induce complete men iscal regeneration, and to develop the technique for implanting the prosthetic appliance in vivo. We de signed a resorbable collagen-based scaffold and con ducted in vitro and in vivo studies. In vivo, the scaffold was implanted in the knees of immature swine and mature canines and evaluated clinically, histologically, and biochemically. Because the canine stifle joint me niscus is more clinically relevant to the human menis cus, this paper emphasizes those results.

We studied 24 mixed breed dogs (14 males and 10 females) with an average weight of 25.5 kg (range, 20 to 35) that were obtained from a USDA-licensed sup plier. The dogs were deemed clinically and radiograph ically skeletally mature. None of the dogs had a preex isting knee joint abnormality. All dogs underwent an 80% subtotal resection of the medial meniscus bilater ally. A collagen template was implanted in one stifle (N = 24). The contralateral side served as a control: 12 dogs had a total resection alone and the other 12 dogs had an immediate replantation of the autologous meniscus.

Results were tabulated at 3, 6, 9, and 12 months. At final evaluation, before the animals were euthanized, the results were submitted for statistical analysis as well as histologic and biochemical analyses. The results demonstrated that a copolymeric collagen-based scaf fold can be constructed that is compatible with meniscal fibrochondrocyte growth in vitro and in vivo, that does not inhibit meniscal regeneration in an immature pig, and that may induce regeneration of the meniscus in the mature dog.

Although additional studies are necessary to perfect the scaffold and to evaluate the implant in the environ ment of the knee, these studies suggest that effective meniscal regeneration can be supported by an im planted collagen-based scaffold designed to support cellular ingrowth.
The results of fresh-frozen patellar tendon allografts for chronic anterior cruciate ligament deficiency of the knee
Authors: Indelicato Peter A. , Linton Russell C. , Huegel Marty
Published: June 2007

This prospective study was done to evaluate the clinical outcome of fresh-frozen patellar bone-tendon-bone al lograft tissue used as a substitute for chronic insuffi ciency of the anterior cruciate ligament. Forty-one pa tients were followed at a mean of 27 months after surgery. The mean time from injury to reconstruction was 34 months. The same operative procedure and postoperative rehabilitation was performed on each patient. The evaluation method consisted of subjective, objective, and instrumented laxity testing. Thirty-seven patients (90%) thought their knee was normal or im proved after surgery and had no further episodes of giving way.

The combined modified Hughston Knee Score re vealed 30 patients (73%) with an excellent or good result and 9 patients (22%) with a fair or poor result. The mean postoperative Lysholm Knee Score was 91 (range, 56 to 100). Thirty-two had a negative pivot shift (78%). The postoperative KT-1000 arthrometer re vealed 37 patients had an injured-to-uninjured differ ence of 5 mm or less (mean, 1.32 mm; range, 0 to 5). There were three traumatic failures at 24 months post operatively in this group. There was no rejection phe nomenon noted postoperatively. In addition, clinical observation showed less postoperative morbidity when compared to a matched autogenous patellar tendon control group.
Injuries in adolescent and preadolescent boys at two large wrestling tournaments
Authors: Lorish Thomas R. , Rizzo Thomas D. , Ilstrup Duane M. , Scott Steven G.
Published: June 2007

We evaluated injury patterns at two wrestling tourna ments involving 1742 participants, aged 6 to 16 years. The overall injury rate was 12.7%. Injuries requiring withdrawal from the tournament occurred in 4.6% of the participants. Of all participants, 3% sustained an injury in their first match, and 1.1 % sustained an injury during their first match that required withdrawal from the tournament. Primary areas of injury were the upper extremity (33%) and the neck and back (24%). Wil coxon rank-sum tests revealed that increasing age and increasing weight were correlated with injury, whereas multiple logistic regression analysis revealed that only increasing age was correlated with injury. These find ings suggest the need for medical supervision at large wrestling tournaments, where it is likely that severe injuries will occur. In addition, older wrestlers and per haps heavier wrestlers are at an increased risk for injury.
Regeneration of the semitendinosus and gracilis tendons following their transection for repair of the anterior cruciate ligament
Authors: Cross Mervyn J. , Roger Greg , Kujawa Ples , Anderson Ian F.
Published: June 2007

Apparent regeneration of the tendons of the semiten dinosus and gracilis muscles after their use for anterior cruciate ligament reconstruction was noted during rou tine followup of 225 patients. From this group, four patients were selected for thorough examination, in cluding magnetic resonance imaging, electromyo graphic studies, strength testing, and clinical examina tion. The results demonstrate that these tendons ap pear to regrow and are probably functional.
A profile of the musculoskeletal characteristics of elite professional ballet dancers
Authors: Hamilton William G. , Hamilton Linda H. , Marshall Peter , Molnar Marika
Published: June 2007

Twenty-eight principal dancers and soloists from Amer ica's two most famous ballet companies were exam ined for anthropometric measurements, including flexi bility, muscle strength, and joint range of motion. Both male and female dancers were flexible, but not hyper- mobile, and did not differ significantly from each other. Marked differences were found between the range of motion of the hip and ankle in the dancers and the norms for the general population. The increased exter nal rotation of the hip in women was accompanied by a loss in internal rotation, resulting in an increased range of motion with an externally rotated orientation. The men, however, lost more internal rotation than they gained in external rotation. These data raise the pos sibility of a torsional component to the turned-out hip position in elite female professional ballet dancers. In addition, significant anatomic differences separate elite dancers of both sexes from the normal population.
Diagnostic value of ultrasonography in partial ruptures of the Achilles tendon
Authors: Kälebo Peter , Allenmark Christer , Peterson Lars , Swärd Leif
Published: June 2007

We evaluated 37 patients with surgically treated Achilles tendon disorders, comparing findings of pre operative ultrasonography with findings at surgery, to investigate the reliability of ultrasonography in diagnos ing partial ruptures of the Achilles tendon. Discontinuity of tendon fibers, focal sonolucencies, and localized tendon swelling were positive findings suggestive of partial ruptures. We found the use of ultrasonography to be safe and reliable, with a sensitivity of 0.94, a specificity of 1.00, and an overall accuracy of 0.95.
Partial rupture of the patellar ligament
Authors: Karlsson Jon , Kälebo Peter , Goksör Lars-Ake , Thomee Roland , Swärd Leif
Published: June 2007

Eighty-one patients with 91 partial ruptures of the pa tellar ligament verified by ultrasonography were treated conservatively with a standardized training program based on the principles of eccentric loading. The partial ruptures were quantified by measuring the length of the hypoechoic lesion using ultrasonography in longi tudinal projection. The partial ruptures were then di vided into three groups: Grade I (<10 mm), Grade II (10 to 20 mm), and Grade III (>20 mm). The results after the training program were significantly better in Grade I ruptures than in Grades II and III. The overall need for surgery was 29.6%: highest in Grade III ruptures (38.5%) and lowest in Grade I ruptures (6.6%). The outcome of conservative management, as well as the need for surgery of partial ruptures of the patellar ligament, may to some extent be predicted by the use of ultrasonography.
A biomechanical evaluation of taping and bracing in reducing knee joint translation and rotation
Authors: Anderson Kyle , Wojtys Edward M. , Loubert Peter V. , Miller Russell E.
Published: June 2007

We used five randomly selected cadaver specimens to evaluate the Anderson Knee Stabler and the Lenox Hill Knee Brace, individually and in combination with an anterior cruciate ligament protective tape method. Re duction of total laxity, as well as a defined pathologic anterior-posterior translation and internal-external ro tation, was tested after the anterior cruciate and medial collateral ligaments of the specimens had been sec tioned. Displacements were produced pneumatically; loads were applied to the tibia with the knee in 50° of flexion.

The tape and Lenox Hill Brace combination showed the greatest reduction in both anterior-posterior trans lation and internal-external rotation. The Lenox Hill Brace and the tape method used individually both re stricted anterior-posterior translation and internal-ex ternal rotation better than the Stabler Brace alone. This study provides objective evidence of the restraining capabilities of these protective systems that may prove to be beneficial in the clinical setting.
Occurrence of free nerve endings in the soft tissue of the knee joint
Authors: Biedert Roland M. , Stauffer Edi , Friederich Niklaus F.
Published: June 2007

We present a comprehensive histologic study of neu rologic structures in 18 static and dynamic knee struc tures of 8 cadaveric knees. Qualitative and quantitative measurements of the incidence of free nerve endings in the structures were recorded. The highest amounts of afferent nerve fibers type IVa were found in the retinacula, the patellar ligament, the pes anserinus, and in the ligaments of Wrisberg and Humphry; the lowest amount was found in the anterior cruciate ligament. There is a positive correlation between the number of mechanoreceptors per standardized area unit and the clinical presentation of certain knee disorders.
KT-1000 arthrometer: Conscious and unconscious test results using 15, 20, and 30 pounds of force
Authors: Highgenboten Carl L. , Jackson Allen W. , Jansson Ken A. , Meske Neil B.
Published: June 2007

A recent published report indicated that the reliability and validity of anterior laxity measurements obtained by using the KT-1000 arthrometer were questionable. The purpose of our study was to examine the diagnos tic validity of anterior laxity measurements testing pa tients in conscious and unconscious states using the KT-1000 arthrometer at 15, 20, and 30 pounds of force. The sample included 68 patients with confirmed ante rior cruciate ligament disruption. They were given an terior-posterior drawer tests at 20° in both unconscious and conscious states; measurements were recorded at 15, 20, and 30 pounds of force. The results indicated that the measurements in the unconscious state were significantly higher (P < 0.01) than the values obtained in the conscious state. The anterior cruciate ligament- disrupted knees produced significantly higher (P < 0.01) anterior laxity. The difference between anterior cruciate ligament-disrupted knees and normal knees grew sig nificantly larger (P < 0.01) as force increased. More patients demonstrated a difference >2 mm between anterior cruciate ligament-disrupted knees and normal knees at 30 pounds (81 % to 83%) than at 20 pounds (64% to 72%) of force. Seventy-nine percent of the patients demonstrated a compliance index difference >1 mm using 15 and 30 pounds between the normal and anterior cruciate ligament-disrupted knee. These data provide statistical validity for the compliance index and support for the use of anterior laxity measurements at 30 pounds of force. However, approximately 20% of these patients did not demonstrate an anterior cruciate ligament-disrupted-normal knee difference >2 mm or a compliance index difference of >1 mm.
Loss of motion after anterior cruciate ligament reconstruction
Authors: Harner Christopher D. , Irrgang James J. , Paul Jonathan , Dearwater Steven , Fu Freddie H.
Published: June 2007

We did a retrospective review and follow-up examina tion to investigate the incidence, risk factors, and out come of patients who developed loss of motion after arthroscopic anterior cruciate ligament reconstruction. Two hundred forty-four patients with a minimum fol lowup of 1 year were reviewed. Loss of motion (defined as a loss of extension of more than I0° or flexion of less than 125°) was identified in 27 patients for an overall incidence of 11.1%. Factors associated with loss of motion included acute reconstruction (less than 1 month from initial injury), male sex, and concomitant medial collateral ligament repair or posterior oblique ligament reefing or both. Twenty-one patients required surgery to regain their motion; three patients required a second procedure.

Twenty-one of 27 patients with loss of motion under went a detailed followup and were compared with 24 randomly chosen controls who had a normal range of motion after anterior cruciate ligament reconstruction. At followup, patients who experienced loss of motion had a significant decrease in noninvolved to involved knee extension and flexion compared to the control patients. There was no difference between our patients and the controls regarding patellofemoral problems, anterior knee laxity, and functional strength. Sixty- seven percent of patients with loss of motion had a good or excellent result in comparison to 80% of the controls.
Cryotherapy-induced nerve injury
Authors: Bassett Frank H. , Kirkpatrick John S. , Engelhardt David L. , Malone Terry R.
Published: June 2007

Cryotherapy is a frequently used therapeutic modality in the treatment of athletic injuries. Peripheral nerve injury can result from the use of cryotherapy and cause temporary disability for the athlete. Six cases of periph eral nerve injury are reviewed. All cases resolved spon taneously. To avoid this complication, one should con sider the location of major peripheral nerves, the thick ness of the overlying subcutaneous fat, and the duration of tissue cooling.
Extensor mechanism function after patellar tendon graft harvest for anterior cruciate ligament reconstruction
Authors: Rosenberg Thomas D. , Franklin Jonathan L. , Baldwin G. Nicholas , Nelson Kim A.
Published: June 2007

We evaluated extensor mechanism function in 10 pa tients after they had arthroscopically assisted ACL reconstruction using the central third of the patellar tendon. The patients were randomly selected 12 to 24 months after reconstruction. All had rehabilitation where range of motion was initiated within the 1 st postoperative week. All patients stated that they were satisfied and considered their knee to be stable. The KT-1000 maximum measurements (30 to 40 pounds) averaged an increase of 1.7 mm when compared with the opposite knee. Subjective complaints, such as an terior knee pain, grating, and weakness, were common and only 3 of 10 patients returned to all of their preinjury sports.

Persistent radiographic abnormalities were common. Physical examination and functional testing also re vealed persistent dysfunction of the extensor mecha nism in patients with radiographic abnormalities. Isoki netic testing at 60 deg/sec showed an average quad riceps deficit of 18% compared to the normal extremity. Axial computed tomography scans revealed significant decrease in quadriceps cross-sectional area. Magnetic resonance imaging and computed tomography con firmed persistent defects at the harvest site; there was significant anterior knee scar formation in these pa tients.

Despite achieving ligamentous stability, patients still experienced permanent weakness, functional deficits, patellar chondrosis, and pain after ACL reconstruction using the central one-third of the patellar tendon.
Patterns of meniscal injury associated with acute anterior cruciate ligament injury in skiers
Authors: Paletta George A. , Levine David S. , O'Brien Stephen J. , Wickiewicz Thomas L. , Warren Russell F.
Published: June 2007

To determine if the incidence and patterns of meniscal injury associated with acute anterior cruciate ligament injury in skiers are different from those seen in individ uals injured in nonskiing athletic activities, we reviewed the records of 150 patients with acute anterior cruciate ligament injuries. All patients had undergone arthro scopic evaluation within 21 days from the time of injury. There were 75 individuals who were injured while skiing and 75 individuals who sustained an injury in some other high-load athletic activitiy. Associated meniscal injury was documented at the time of arthroscopy and characterized by location, region, zone, depth, shape, size, and stability.

Thirty-one of 75 skiers had an associated meniscal injury as compared to 47 of 75 of the nonskiers. This suggested a strong trend of decreased incidence of meniscal injury in the skier group, but the nonskiers had a higher incidence of major meniscal tears that required repair or partial meniscectomy. The location of the meniscal tear was also significantly different. The incidence of isolated lateral meniscal injury in skiers was higher than in nonskiers. There was a strong trend of increased incidence of medial meniscal involvement in the nonskiers than in the skiers. While there was no difference in the zone or region of tear between the two groups, the skier group was more likely to have a longitudinal tear of the posterior horn of the lateral meniscus. In both groups, lateral meniscal tears were more likely to require conservative treatment or partial meniscectomy while medial meniscal tears were more likely to be repaired than excised.
Human torque velocity adaptations to sprint, endurance, or combined modes of training
Authors: Shealy Marilyn J. , Callister Robin , Dudley Gary A. , Fleck Steven J.
Published: June 2007

We had groups of athletes perform sprint and endur ance run training independently or concurrently for 8 weeks to examine the voluntary in vivo mechanical responses to each type of training. Pre- and posttrain ing angle-specific peak torque during knee extension and flexion were determined at 0, 0.84, 1.65, 2.51, 3.35, 4.19, and 5.03 radian·sec-1 and normalized for lean body mass. Knee extension torque in the sprint- trained group increased across all test velocities, the endurance-trained group increased at 2.51, 3.34, 4.19, and 5.03 radian·sec,-1 and the group performing the combined training showed no change at any velocity. Knee flexion torque of the sprint and combined groups decreased at 0.84, 1.65, and 2.51 radian·sec.-1 Knee flexion torque in the sprint-trained group also decreased at 0 radian·sec-1 and in the combined group at 3.34 radian·sec.-1 Knee flexion torque in the endurance- trained group showed no change at any velocity of contraction. Mean knee flexion:extension ratios across the test velocities significantly decreased in the sprint- trained group. Knee extension endurance during 30 seconds of maximal contractions significantly increased in all groups. Only the sprint-trained group showed a significant increase in endurance of the knee flexors. These data suggest that changes in the voluntary in vivo mechanical characteristics of knee extensor and flexor skeletal muscles are specific to the type of run training performed.
Outcome of conservative and surgical management of navicular stress fracture in athletes
Authors: Khan Karim M. , Fuller Peter J. , Brukner Peter D. , Kearney Chris , Burry Hugh C.
Published: June 2007

Eighty-two athletes with 86 clinical navicular stress fractures, all imaged with computerized tomography, were followed for an average of 33 months (range, 6 to 108) after diagnosis. Initial treatment consisted of at least 6 weeks of nonweightbearing cast immobilization for 22 fractures, at least 6 weeks of limitation of activity with continued weightbearing for 34 fractures, and a period of less than 6 weeks of conservative treatment for another 19 fractures. Five patients attempted to continue playing sports. Six patients had immediate surgery.

Nineteen of 22 patients (86%) who had initial non weightbearing cast immobilization treatment returned to sports, compared with only 9 of 34 patients (26%) who initially continued weightbearing with limited activ ity (P < 0.001 ). After failure of the latter treatment, successful outcomes were seen for 6 of 7 patients (86%) treated with nonweightbearing cast immobiliza tion, while 11 of 15 patients (73%) who had one surgical procedure were able to return to sports.

These results indicate that nonweightbearing cast immobilization is the treatment of choice for navicular stress fractures. Also, this treatment compares favor ably with surgical treatment for patients who present after failed weightbearing treatments.

Computerized tomographic appearances of healing fractures do not necessarily mirror clinical union, and postimmobilization management should be monitored clinically.
Osteochondral lesions of the talus
Authors: Loomer Richard , Fisher Carol , Lloyd-Smith Robert , Sisler John , Cooney Tom
Published: June 2007

We report demographic, clinical, and imaging data on 92 patients with osteochondral lesions of the talus collected in one center between 1981 and 1992. All patients reported pain as their primary symptom. Ninety-four percent of the patients reported pain with activity. Physical examination was unhelpful. Using newer imaging techniques (bone scan and computed tomography) and with increased awareness, we have observed a sevenfold increase in the diagnostic fre quency of osteochondral lesions of the talus between the years 1981 to 1986 and 1987 to 1992. Bone scan is an excellent screening tool for patients with chronic ankle pain and has 99% sensitivity in depicting osteo chondral lesions.16 Computed tomography demon strated a previously unclassified lesion, the radiolucent defect, which accounts for 77% of the lesions in this series. We have therefore modified the Berndt and Harty classification system, basing it on radiographic appearance (principally computed tomography) and adding the radiolucent lesion.

Fifty-eight patients were treated surgically. Anterior and midtalar lesions are now approached arthroscopi cally. Surgical treatment of the radiolucent lesion, con sisting of curettage and drilling, gives 42% excellent and 32% good results. Pain relief often occurs within months of surgery, but healing of the lesion requires years, and some may persist indefinitely.
An in vitro dynamic evaluation of prophylactic knee braces during lateral impact loading
Authors: Erickson Ann R. , Yasuda Kazunori , Beynnon Bruce , Johnson Robert , Pope Malcolm
Published: June 2007

To determine the ability of prophylactic knee braces to reduce or limit medial collateral and anterior cruciate ligament elongation under dynamic loading conditions, we used cadaveric specimens that had a surrogate soft tissue material that matched the tissue compliance of in vivo contracted muscles.

Eight cadaveric specimens were fitted with four pro phylactic knee braces and instrumented with Hall Effect Strain Transducers on both the medial collateral and anterior cruciate ligament. Each specimen was mounted in a testing frame while a lateral impact was applied to the knee joint by a pendulum at levels below the injury threshold. Legs were tested at 0° and 30° of knee flexion, both with and without an intact anterior cruciate ligament.

The maximum elongation for each ligament was cal culated as a percentage of the initial measured length. The addition of a prophylactic knee brace significantly reduced the level of impact force at the point of impact, but this did not result in a significant reduction of anterior cruciate ligament elongation for any test. Al though not significant, all braces tested were more effective at reducing medial collateral ligament elonga tion during a lateral impact with the knee flexion at 30° than at 0°.
Comparison of closed and open kinetic chain exercise in the anterior cruciate ligament-deficient knee
Authors: Yack H. John , Collins Cynthia E. , Whieldon Terry J.
Published: June 2007

The purpose of this study was to quantify the amount of anterior tibial displacement occurring in anterior cru ciate ligament-deficient knees during two types of re habilitation exercises: 1) resisted knee extension, an open kinetic chain exercise; and 2) the parallel squat, a closed kinetic chain exercise. An electrogoniometer system was applied to the anterior cruciate ligament- deficient knee of 11 volunteers and to the uninvolved normal knee in 9 of these volunteers. Anterior tibial displacement and the knee flexion angle were meas ured during each exercise using matched quadriceps loads and during the Lachman test. The anterior cru ciate ligament-deficient knee had significantly greater anterior tibial displacement during extension from 64° to 10° in the knee extension exercise as compared to the parallel squat exercise. In addition, the amount of displacement during the Lachman test was significantly less than in the knee extension exercise, but signifi cantly more than in the parallel squat exercise. No significant differences were found between measure ments in the normal knee. We concluded that the stress to the anterior cruciate ligament, as indicated by ante rior tibial displacement, is minimized by using the par allel squat, a closed kinetic chain exercise, when com pared to the relative anterior tibial displacement during knee extension exercise.
The strength characteristics of internal and external rotator muscles in professional baseball pitchers
Authors: Wilk Kevin E. , Andrews James R. , Arrigo Christopher A. , Keirns Michael A. , Erber Donna J.
Published: June 2007

The purpose of this study was to establish a data base regarding the isokinetic muscular performance charac teristics of the external/internal rotator muscles of professional baseball pitchers. One hundred fifty healthy professional baseball pitchers were evaluated by use of a Biodex isokinetic dynamometer. The sub jects tested had a mean age of 23.4 years and a mean body weight of 199 pounds. Isokinetic tests were per formed concentrically at 180 and 300 deg/sec for both the throwing and nonthrowing shoulders. Testing pro cedures regarding positioning and stabilization followed established guidelines. The testing protocol and actual test repetitions were standardized for each subject. Statistical analysis was performed using the Pearson Product Moment Correlation and paired t-tests. Deter mination of the correlation coefficient was made at the P < 0.05 level of significance.

Test results for bilateral comparison of mean peak torque for the throwing and nonthrowing shoulders indicated no statistically significant difference between the internal rotators at both test speeds, or for the external rotators at 300 deg/sec. There was a signifi cant statistical difference at the 180 deg/sec test speed for the external rotators. The external/internal rotator strength ratio indicated a 65% ratio at 180 deg/sec and a 61 % ratio at 300 deg/sec. Data were also collected for mean peak torque/body weight ratios of the throw ing shoulder to establish a data base in professional throwers.

This study offers clinical relevance in establishing a muscle performance profile for the professional thrower. This data base can therefore be used as criteria that should be met before an injured pitcher can be returned to throwing at the professional baseball level.
A survey of interfering shoulder pain in United States competitive swimmers
Authors: McMaster William C. , Troup John
Published: June 2007

The prevalence of shoulder pain in United States com petitive swimmers has not been extensively surveyed but is perceived as common. To evaluate this concern, a questionnaire survey was conducted on 1262 United States swimmers: 993 age group, 198 senior develop ment, and 71 national team athletes. We sought to identify the incidence of interfering shoulder pain in this population and how it is influenced by various training tasks. The prevalence of current shoulder pain in these groups varied between 10% (age group) to 26% (na tional team) and increased with time in the sport. In those athletes with a painful shoulder, weight training, use of hand paddles, kickboard use, stretching, and various resistance activities aggravated the painful shoulder. This survey has identified that interfering shoulder pain is present in a substantial number of competitive swimmers.
Arthroscopic treatment of synovial impingement of the ankle
Authors: Meislin Robert J. , Rose Donald J. , Parisien J. Serge , Springer Stuart
Published: June 2007

Twenty-nine cases of operative arthroscopy of the an kle were done between 1985 and 1989 for synovial impingement of the ankle. The average age of the patients was 37 years. All patients (17 men, 12 women) reported an earlier history of injury, with 24 of the patients (83%) noting chronic ankle pain after an inver sion injury and 5 of the patients (17%) reporting a previous ankle fracture. Physical examination elicited anterolateral tenderness at the ankle in all cases with associated anteromedial pain in 4 patients. A demon strable "click" was evident in 6 of the patients (21 %) on forced dorsiflexion of the ankle.

All patients failed conservative treatment including physical therapy and nonsteroidal antiinflammatory drugs. Surgery was performed at an average of 36 months postinjury. Ankle arthroscopy revealed exten sive hypertrophic synovial thickening and scar tissue anterolaterally, indicating synovial impingement in all patients. Associated chondromalacia of the distal tibia was seen in 21 % of the patients. Operative arthroscopy included partial synovectomy and debridement of the hypertrophic tissue and partial shaving chondroplasty of the tibia when indicated. Postoperatively, patients were weightbearing as tolerated. Results were as sessed subjectively and objectively.

At 25-month followup 26 patients had excellent or good results and 3 had fair results; there were no poor results. There were no major complications, including infection or neurovascular compromise. The 3 patients with associated ankle instability comprised the "fair" result group and eventually required lateral ankle recon struction. Thus, chronic ankle pain due to synovial impingement can be safely, predictably, and effectively treated by operative ankle arthroscopy.