bluuebunny/crossref_metadata_2025 huggingface dataset:
Biomechanical and histological observations of the dog patellar tendon after removal of its central one-third
Authors: Burks Robert T. , Haut Roger C. , Lancaster Ronald L.
Published: June 2007

The use of a central one-third patellar tendon as an autograft for surgical reconstruction of a damaged cru ciate ligament is common. Few complications of its use have been reported. However, recent clinical studies indicate that decreased quadriceps strength, de creased range of motion, decreased thigh circumfer ence, and patellofemoral problems can be associated with this procedure. Some of these complications may result from alterations in the biomechanical properties of the remaining patellar tendon. The objective of this study was to examine biomechanically and histologi cally the fate of the remaining patellar tendon after removal of its central one-third.

Three groups of dogs were used for this study. On one knee the central third of the patellar tendon was removed, while the contralateral side was used as a control. One group was immediately euthanized, while the other two groups were euthanized at 3 and 6 months. Control and operated patella-patellar tendon- tibia preparations were harvested and stretched to failure at 100% strain per second.

The 3 and 6 month groups had a 10% decrease in length of the operated patellar tendon versus the con tralateral control. There was a very significant increase in cross-sectional area of the patellar tendon at 3 months, and a further increase at 6 months. The failure load was 70% of the controls at 3 months and 60% of the controls at 6 months.

The stiffness and modulus of the operated tendon within the physiologic range were dramatically reduced to 70% and 33% of controls at 6 months, respectively. These overall results were observed with the central one-third defect closed or left open in surgery.

This study indicated that the canine patellar tendon had not fully recovered 6 months after removal of its central third. The biomechanical changes observed in the remaining tendon may help explain the loss of quadriceps strength that has been documented in re cent clinical studies after using patellar tendon grafts.
The effect of joint velocity on the contribution of the antagonist musculature to knee stiffness and laxity
Authors: Hagood S. , Solomonow M. , Baratta R. , Zhou B.H. , D'Ambrosia R.
Published: June 2007

The electromyographic (EMG) coactivation patterns of the knee flexors and extensors when acting as antag onists were studied as a function of limb velocity to assess their contribution to joint stiffness and laxity.

Normalized antagonist coactivation patterns devel oped from surface EMG recordings from the hamstrings and quadriceps during maximal effort isokinetic exten sion and flexion, respectively, demonstrated character istic variations as the joint velocity increased from 15 deg/sec up to 240 deg/sec. The two-tailed t-test ( P < 0.1) was performed on the data obtained from eight normal knees. The results indicate that both hamstrings and quadriceps demonstrate a significant increase (>100%) in their antagonist coactivation pattern during the final 40° of fast extension and flexion movements, respectively, as limb velocity increases. A minor de crease in antagonist activity of the hamstrings (24%) and quadriceps (8%) was evident during the initial phase of the extension and flexion movements, respec tively, as joint velocity increased.

We concluded that as limb velocity is increased, there is a substantial reflexive (unintentional) increase in the contribution of the antagonist musculature to joint stiff ness and reduction of laxity. The results also suggest that strength training of the hamstrings (rather than quadriceps) should be considered as a modality for conservative treatment of ACL deficiencies, as well as an adjunct to surgical reconstruction. Such training can also reduce the risk of high performance athletes in a reflexive manner by increasing joint stiffness.
Arthroscopic shoulder decompression development and application
Authors: Paulos Lonnie E. , Franklin Jonathan L.
Published: June 2007

The purpose of this study was to critically evaluate the results of 80 consecutive subacromial decompressions in 76 patients with impingement syndrome and to as sess the value of arthroscopy for subacromial de compression. The average followup was 32 months. The charts, radiographs, and clinical findings of all patients were reviewed. There were 57 males and 19 females, with a mean age of 41 years. Subjective, objective, and functional results were assessed. The greatest improvement was seen in the areas of pain with activity, pain at night, and use of medications. Impingement signs had decreased significantly at final followup. The procedure allowed an early return to work and competitive athletics.

Repeat surgery was necessary in eight cases: three full thickness rotator cuff repairs, two stabilization pro cedures, two open debridements, and one biceps ten odesis and excision of the distal clavicle. An important finding was the number of unsuspected diagnoses that were made during arthroscopy. Twelve patients had significant labral tears, seven patients had complete rotator cuff tears, four patients had biceps tendon fraying, and two patients had loose bodies in the gle nohumeral joint. In most of these shoulders the intra articular lesions would not have been diagnosed by open subacromial decompression.

Radiographic evaluation suggested that the "outlet view" can be helpful in determining depth of bony resection and may be a prognostic indicator. Patients who underwent simple decompression rather than bony resection tended to be younger and had less Stage III impingement changes, and they generally had a slightly better final outcome. Patients who had compensation injuries generally had a poorer outcome. In reviewing our results, it appears that arthroscopic subacromial decompression can be a successful alternative to open decompression. The key to success for closed de compression is related to 1) accurate diagnosis, 2) selective treatment, 3) adequate bone resection when required, and 4) repair of full thickness rotator cuff tears in the active patient. Postoperative rehabilitation, which includes early range of motion, is critical.
An in vitro study of an intraarticular and extraarticular reconstruction in the anterior cruciate ligament deficient knee
Authors: Draganich Louis F. , Reider Bruce , Ling Mary , Samuelson Mathew
Published: June 2007

The biomechanical effectiveness of an extraarticular ACL reconstruction, an intraarticular ACL reconstruc tion, and the combination of these on both anterior stability and internal rotational stability of the ACL de ficient knee was investigated in six cadaver knees. The extraarticular reconstruction consisted of the Müller anterolateral femorotibial ligament iliotibial band teno desis, and the intraarticular reconstruction used the middle third of the patellar tendon in the manner of Clancy.

The extraarticular reconstruction was found to over- constrain internal tibial rotation of the ACL excised knee between 30° and 90° ( P < 0.05). While the isolated extraarticular reconstruction did not return normal an terior stability to the ACL deficient knee ( P < 0.05), it did significantly reduce the anterior laxity of the ACL deficient knee between 30° and 90° of knee flexion ( P < 0.05).

For the combined reconstruction, the intraarticular procedure was performed and then only enough ten sion was applied to the extraarticular reconstruction to take up slack in the tenodesis without shifting the rotatory position of the tibia from that produced by the intraarticular procedure alone. Neither the intraarticular reconstruction nor the combined procedure resulted in any significant shifts from normal ( P < 0.05) in the rotatory position of the unloaded tibia; during loading neither resulted in rotational displacements significantly different from normal; and both of these procedures reduced the increased anterior laxity of the ACL defi cient knee to a level not statistically different from normal.

Because the extraarticular reconstruction shared the load when performed with the intraarticular reconstruc tion as part of a combined procedure, we concluded that it would be useful as an adjunctive procedure in appropriate clinical situations.
Long distance running and osteoarthrosis
Authors: Konradsen Lars , Berg Hansen Else-Marie , Søndergaard Lars
Published: June 2007

In order to evaluate the effect of long-term, long dis tance running on the incidence of degenerative joint disease in the lower extremities, we examined the hips, knees, and ankles of 30 long distance runners who had been serious competitive runners in the early 1950s (at the age of 20 to 30 years). Of three runners who were no longer active, one had stopped running in the late 1970s because of osteoarthrosis of both the lower and upper extremity joints. The remaining 27 runners (90%) were still active, having run 20 to 40 km/week (12 to 24 miles/week) for a median of 40 years. Subjective, objective, and roentgenographic data were compared with the data for 27 nonrunning controls matched as to age, weight, height, and occupation. No differences in joint alignment, range of motion, or complaints of pain were found between runners and nonrunners. Roent genographic examinations for cartilage thickness, grade of degeneration, and osteophytosis were also without significant differences between the two groups. Thus, our observations suggest that a lifetime of long distance running at mileage levels comparable to those of recreational runners today is not associated with premature osteoarthrosis in the joints of the lower extremities.
Reproducibility of Genucom knee analysis system testing
Authors: Wroble Randall R. , Grood Edward S. , Noyes Frank R. , Schmitt David J.
Published: June 2007

The Genucom knee analysis system was studied to determine the reproducibility of test results. In the first phase of the study we investigated the reproducibility of anterior/posterior stress tests at 30° and 90° of flexion and varus/valgus stress tests at 20° of flexion in 10 control subjects during three seatings on 3 sep arate days. In the second phase we studied the effect of errors in the digitization procedure (a part of the patient installation process) on anterior/posterior trans lation measurements. In the third phase we studied the reproducibility of a battery of tests in patients with chronic unilateral ACL deficient knees. The test battery was repeated 8 times on each knee on 6 separate days.

In Phase I, analysis of variance revealed no significant differences between tests within a single seating. The day-to-day variance of all subjects was not significant, but we found a significant interaction between day and subject which was due to significant day-to-day differ ences in individual subjects.

We found in Phase II that changing the location of the tibial joint line digitization points in the anterior/ posterior or proximal/distal direction affected anterior/ posterior translation measurements. Effects were larger at 30° of flexion than at 90° and when both the medial and lateral points were moved. Movement of the femoral condylar points resulted in a similar pattern of effects.

In Phase III, although we found significant differences between our two examiners, there were no significant intraexaminer test-to-test (within seating) effects. Ad ditionally, while there was no significant day-to-day variance overall, we found a significant interaction be tween day and subject. This was due to significant day- to-day differences in individual subjects.

The results indicate that since measurements vary from day-to-day, care must be taken in interpreting the meaning of a single measurement or even of repeated measurements made within a single seating. We advise meticulous care in the digitization procedure, diligence in assuring patient relaxation, and attention to detail throughout.
The anatomy and histology of the inferior glenohumeral ligament complex of the shoulder
Authors: O'Brien Stephen J. , Neves Manuel C. , Arnoczky Steven P. , Rozbruck S. Robert , Dicarlo Edward F. , Warren Russell F. , Schwartz Robert , Wickiewicz Thomas L.
Published: June 2007

The gross and histologic anatomy of the inferior glenohumeral ligament was studied in 11 fresh frozen cadaver shoulders. Arthroscopic observations of the joint capsule through the normal range of motion re vealed that the inferior glenohumeral ligament is actually a complex of structures consisting of an anterior band, a posterior band, and an interposed axillary pouch. While these components of the inferior glenohumeral ligament complex were present in all 11 specimens, they were best demonstrated in some shoulders by placing the humeral head in internal or external rotation in varying degrees of abduction. Histologic examination of the joint capsule revealed that the anterior and posterior bands of the inferior glenohumeral ligament complex were readily identifiable as distinct structures comprised of thickened bands of well-organized colla gen bundles.

Although slight variations were noted in the attach ment sites of the anterior and posterior bands to the glenoid, the inferior glenohumeral ligament complex was observed to attach to the humeral neck in one of two distinct configurations. A collar-like attachment, in which the entire inferior glenohumeral ligament complex attaches just inferior to the articular edge of the humeral head, was observed in six specimens. In the remaining five specimens, the attachment was in the shape of a "V," with the anterior and posterior bands attaching adjacent to the articular edge of the humeral head and the axillary pouch attaching at the apex of the "V" distal to the articular edge.

The orientation and design of the inferior glenohu meral ligament complex supports the functional con cept of this single structure as an important anterior and posterior stabilizer of the shoulder joint.
Anterior cruciate ligament injury: Evaluation of intraarticular reconstruction of acute tears without repair
Authors: Shelbourne K. Donald , Whitaker H. Jeffrey , McCarroll John R. , Rettig Arthur C. , Hirschman Lynne D.
Published: June 2007

To evaluate the effectiveness of our treatment regimen, we retrospectively studied the surgically treated knees of 155 athletes, aged 15 to 42 years, who had sustained acute ACL tears. All were treated with ligament excision and intraarticular bone-patellar tendon-bone recon struction followed by early motion with emphasis on full extension. The follow-up period ranged from 2 to 7 years. Of the 155 patients, 140 were available for final followup at a minimum of 2 years after reconstruction. The patients were evaluated by objective measures (KT-1000, Cybex, Lachman test, range of motion, and postoperative competition level) and subjective assess ment scores (pain, swelling, stability, activity level, walk ing, stair climbing, running, jumping, or twisting). The subjective scores were tabulated for stability level, total score, and activity level.

After the patients achieved full range of motion, the KT-1000 measurements at a 20 pound force revealed an average difference of 1.3 mm between the injured and noninjured knees. All but 3 of the 140 patients had a firm endpoint on the Lachman test, and the Cybex tests showed a mean hamstring strength of 98% and mean quadriceps strength of 90%. Sixty of the 69 varsity athletes who were eligible to play returned to preinjury competition level the following season. One had reconstruction failure and eight chose not to con tinue competition for academic reasons. The question naire score average was 92.7 (maximum, 100 points, normal athletic knee score 93.5).

We concluded that the surgical procedure, with em phasis on early full extension postoperatively, achieved excellent results and provided a stable knee.
Soccer injuries to the brain
Authors: Tysvaer Alf T. , Løchen Einar A.
Published: June 2007

Thirty-seven former soccer players of the National Foot ball Team of Norway were individually examined with an extensive battery of psychologic tests. The neuro psychologic examination demonstrated mild to severe deficits regarding attention, concentration, memory, and judgment in 81 % of the players. This may indicate some degree of permanent organic brain damage, prob ably the cumulative result of repeated traumas from heading the ball.
Chondromalacia and chronic anterior instabilities of the knee
Authors: Conteduca Fabio , Ferretti Andrea , Mariani Pier Paolo , Puddu Giancarlo , Perugia Lamberto
Published: June 2007

In this study, we surveyed a consecutive series of 500 patients who had undergone an open procedure for chronic anteromedial and/or anterolateral instabilities. Those patients who had an open arthrotomy were separated for analysis.

All of the patients were examined before and during surgery. A knee sheet, based on the kind used at the Hughston Orthopaedic Clinic in Columbus, Georgia, was used to record all clinical findings. Chondromalacia of the articular surface of the femur was detected at surgery in 161 patients (32%).

A statistical analysis showed that the variables di rectly influencing degenerative changes of the cartilage are: a previous surgery that did not sufficiently restore joint kinematics (chi square = 20.238, P < 0.001) and a time lapse of more than 30 months between first trauma and surgery (chi square = 21.736; P = 0.001).

A higher score on dynamic (jerk or pivot shift) and static (internal and external anterior drawer) tests, in dicating instability, or a meniscal tear alone do not statistically correlate with chondromalacia, but together they influence degenerative changes of the cartilage.
Tensile properties of the human femur-anterior cruciate ligament-tibia complex
Authors: Woo Savio L.-Y. , Hollis J. Marcus , Adams Douglas J. , Lyon Roger M. , Takai Shinro
Published: June 2007

The structural properties of 27 pairs of human cadaver knees were evaluated. Specimens were equally divided into three groups of nine pairs each based on age: younger (22 to 35 years), middle (40 to 50 years), and older (60 to 97 years). Anterior-posterior displacement tests with the intact knee at 30° and 90° of flexion revealed a significant effect of knee flexion angle, but not of specimen age. Tensile tests of the femur-ACL- tibia complex were performed at 30° of knee flexion with the ACL aligned vertically along the direction of applied tensile load. One knee from each pair was oriented anatomically (anatomical orientation), and the contralateral knee was oriented with the tibia aligned vertically (tibial orientation). Structural properties of the femur-ACL-tibia complex, as represented by the linear stiffness, ultimate load, and energy absorbed, were found to decrease significantly with specimen age and were also found to have higher values in specimens tested in the anatomical orientation. In the younger specimens, linear stiffness (242 ± 28 N/mm) and ulti mate load (2160 ± 157 N) values found when the femur- ACL-tibia complex was tested in the anatomical orien tation were higher than those reported previously in the literature. These values provide new baseline data for the design and selection of grafts for ACL replacement in an attempt to reproduce normal knee kinematics.
The current state of functional knee bracing research
Authors: Cawley Patrick W. , France E. Paul , Paulos Lonnie E.
Published: June 2007

This paper reviews recent research on functional knee bracing. Research is categorized by subject, approach, or technique. The authors conclude that, while there is a good deal of excellent research available, there is little data to assist the clinician in selecting an orthosis for a specific application. The authors recommend that future investigations address the physiologic aspects of functional knee bracing and that brace manufacturers assume more responsibility in the validation of both existing and future brace designs.
Quadriceps contusions
Authors: Ryan Jack B. , Wheeler James H. , Hopkinson William J. , Arciero Robert A. , Kolakowski Keith R.
Published: June 2007

A 3 year study of 117 quadriceps contusions in West Point cadets was undertaken to document the effec tiveness of a three-phased therapy program to return these young athletes to full activity with a normal knee range of motion and without recurrence of injury. The treatment protocol of this study was modeled after the 1973 West Point study of Jackson and Feagin with two major changes: 1) resting the injured leg in flexion (versus extension) and 2) emphasizing early flexion exercises (versus extension). Classification of contu sions was based on knee range of motion at 12 to 24 hours after the injury (mild, >90°; moderate, 45° to 90°; severe, <45°). The average disability time was 13 days for mild, 19 days for moderate, and 21 days for severe contusions. Myositis ossificans developed in 9% of cadets and was associated with five risk factors (knee motion less than 120°, injury occurring during football, previous quadriceps injury, delay in treatment greater than 3 days, and ipsilateral knee effusion).
Arthrofibrosis in acute anterior cruciate ligament reconstruction
Authors: Shelbourne K. Donald , Wilckens John H. , Mollabashy Alla , DeCarlo Mark
Published: June 2007

Arthrofibrosis is a potential complication of acute ACL reconstruction. Arthrofibrosis prevents the patient from regaining full range of motion, particularly the terminal 5° of full extension, postoperatively. We did a retro spective study of 169 acute ACL reconstructions in a population of young athletes (average age, 22 years). We sought to determine the optimal time to perform acute ACL reconstruction with respect to arthrofibrosis and the effects of an accelerated versus conventional rehabilitation program. The short-term results were evaluated by range of motion measurements and 13 week Cybex scores. Patients whose ligaments were reconstructed within the 1 st week after injury (Group I) had a statistically significant (P < 0.05) increased inci dence of arthrofibrosis (limited extension, scar tissue) over patients who had ACL reconstruction delayed 21 days or more (Group III). At 13 weeks after the recon struction procedure, Group III patients scored an aver age of 70% (compared to 51 % for Group I, P < 0.05) on the Cybex evaluation. They also showed a trend toward more flexion of the knee as well as near full extension. Patients who had an ACL reconstruction between 8 and 21 days after injury (Group II) had a similar incidence of arthrofibrosis as Group I when they followed a conventional rehabilitation program postop eratively. However, only a small number of cases (ap proximately 4%) of Group II patients who followed an accelerated postoperative rehabilitation program had any arthrofibrosis—an observation we also made in the Group III patients. The evidence suggests that delaying reconstructive surgery at least 3 weeks from time of acute ACL injury will result in earlier return of strength and, more importantly, a significantly decreased inci dence of arthrofibrosis.
Impact biomechanics of lateral knee bracing
Authors: Paulos Lonnie E. , Cawley Patrick W. , France E. Paul
Published: June 2007

We evaluated the effects of six different prophylactic braces on ACL ligament strain under dynamic valgus loads using a mechanical surrogate limb validated against human cadaveric specimens. Medial collateral ligament and anterior cruciate ligament peak forces, medial collateral ligament and anterior cruciate ligament tension initiation times, and impact safety factors were calculated for both braced and unbraced conditions. These tests were conducted to determine whether or not application of a prophylactic brace might provide protection to the anterior cruciate ligament under valgus loading conditions.

The results of this study indicate that those braces that increased impact duration appear to differentially protect the anterior cruciate ligament more than the medial collateral ligament, and that most of the braces tested appear to provide some degree of protection to the anterior cruciate ligament under direct lateral im pacts. These findings should be confirmed clinically.
Postoperative pulmonary edema in young, athletic adults
Authors: Holmes James R. , Hensinger Robert N. , Wojtys Edward W.
Published: June 2007

Pulmonary edema secondary to postextubation laryn gospasm is a potentially life-threatening problem, de manding early diagnosis and prompt treatment. We believe that this problem has been grossly underesti mated in its incidence, as only seven adults have been reported in the English literature, whereas seven adults have been observed at our institution in only a 24 month period. All were young, healthy, athletic adult males (average weight, 218 pounds) who underwent relatively minor, uncomplicated surgical procedures under gen eral anesthesia.

Five of these patients were collegiate and/or profes sional athletes and had meticulous medical records detailing their clinical course. Clinical laryngospasm was noted immediately following extubation and anesthesia by mask with subsequent pulmonary edema. The di agnoses were confirmed by clinical examination, arterial blood gas determinations or pulse oximetry, and chest roentgenogram. Four adults required reintubation. Six of the seven adults demonstrated very rapid resolution of the pulmonary edema with prompt diagnosis and institution of a therapeutic regimen including oxygen, diuretics, reintubation, and/or positive pressure venti lation. In one patient, the problem was not immediately recognized, and progressed to florid pulmonary edema requiring emergent intubation 14 hours later in the emergency room, and 3 days of mechanical ventilation.

The etiology of pulmonary edema following upper airway obstruction represents an interplay between several factors: cardiogenic and neurogenic mecha nisms, as well as hypoxia contribute. In this group, excessive negative intrathoracic pressure generated by forced inspiration against a closed glottis is the most likely, consistent, and logical explanation.

This study suggests that young, healthy, athletic males may be at increased risk for this complication. We believe that their enhanced ability to generate ex cessive negative intrathoracic pressures is, at least in part, responsible. A heightened awareness of the prob lem in this at-risk group should invoke special consid erations, including choice of anesthesia, precautions on extubation, prolonged monitoring in the recovery phase if laryngospasm is observed or suspected, and rapid therapeutic intervention.
Soccer injuries among elite female players
Authors: Engström Bjorn , Johansson Christer , Tornkvist Hans
Published: June 2007

Injuries occurring in two female elite soccer teams were recorded during 1 year. Of 41 players, 33 (80%) sus tained 78 injuries. The incidence of injury during games was 24/1000 hours, while the incidence during training was 7/1000 hours. The majority (88%) of injuries were localized to the lower extremities, with equal occur rence in the left and right legs. Forty-nine percent of the injuries occurred in the knee or ankle. Most of the injuries were minor (49%), while 36% were moderate and 15% were major. Of the major injuries (N = 12), 10 were due to trauma and 7 (58%) were knee ligament or meniscal tears. Overuse injuries constituted 28% of all injuries and occurred mainly during preseason train ing and at the beginning and end of the competitive season. Traumatic injuries (72%) occurred mainly dur ing games with a predominance at the beginning of the competitive season. Almost 80% of the traumatic inju ries occurred during physical contact with an opponent. Extrinsic factors such as weather, playing surface, tem perature, or the position of the player within the team did not influence the injury rate.

We conclude that female elite soccer players sustain a high incidence of injury. Few injuries were major, but 17% of the players sustained a major knee injury during the year.
Fluid and electrolyte replacement in the ultramarathon runner
Authors: Newmark Stephen R. , Toppo Frank R. , Adams Gary
Published: June 2007

We studied three male runners during three separate ultramarathon races. Serial blood samples were tested for electrolytes, renal function, albumin, calcium, phos phorus, and magnesium. Two runners had aldosterone levels measured during the race and one runner had blood lactate levels measured. All runners ingested an isotonic fluid and electrolyte solution during the race. The runners consumed the solution without medical complications and maintained prerace body weights and hydration levels. Each runner maintained normal endocrine/metabolic parameters. We concluded that it is possible to maintain normal hydration and electrolyte states during a prolonged race, provided that sufficient fluid and electrolyte solutions are ingested.
Anterior capsulolabral reconstruction of the shoulder in athletes in overhand sports
Authors: Jobe Frank W. , Giangarra Charles E. , Kvitne Ronald S. , Glousman Ronald E.
Published: June 2007

From April 1, 1985, through June 30, 1987, 25 skilled athletes with shoulder pain secondary to anterior gle nohumeral instability that had failed to improve with conservative therapy had an anterior capsulolabral re construction. All but one athlete completed a formal rehabilitation program with an average followup of 39 months. The results at followup were rated excellent in 68%, good in 24%, fair in 4%, and poor in 4%. Seven teen patients returned to their prior competitive level for at least 1 year. This operation and rehabilitation program may allow many athletes who participate in overhand activities or throwing sports to return to their prior level of competition.
Posterior tibial tendon rupture in athletic people
Authors: Woods Lee , Leach Robert E.
Published: June 2007

We present our findings in six athletic patients with a ruptured or partially ruptured posterior tibial tendon. Pain in the midarch region, difficulty pushing off while running, and a pronated flattened longitudinal arch are the usual symptoms and physical findings of this injury. Surgical treatment, including reattachment of the rup tured posterior tibial tendon, is effective in restoring some but not all normal function. Nor will surgery restore the flattened longitudinal arch.
Abnormal lower limb symmetry determined by function hop tests after anterior cruciate ligament rupture
Authors: Noyes Frank R. , Barber Sue D. , Mangine Robert E.
Published: June 2007

This study assessed the sensitivity of four different types of one-legged hop tests. The goal was to deter mine alterations in lower limb function in ACL deficient knees. Regression analyses were conducted between limb symmetry as measured by the hop tests and muscle strength, symptoms, and self-assessed func tion.

In 67 patients, 50% had abnormal limb symmetry scores on a single hop test. When the results of two hop tests were calculated, the percent of abnormal scores increased to 62%. The percentage of normal scores indicated that these hop tests had a low sensi tivity rate. However, the high specificity and low false- positive rates allow the tests to be used to confirm suspected defects in lower limb function. Statistical trends were noted between abnormal limb symmetry on the hop tests and low velocity quadriceps isokinetic test results.
Retrospective direct comparison of three intraarticular anterior cruciate ligament reconstructions
Authors: Holmes Peter F. , James Stan L. , Larson Robert L. , Singer Kenneth M. , Jones Donald C.
Published: June 2007

A long-term retrospective study (minimum 5 years) was done looking at three groups of anterior cruciate defi cient knee patients using both subjective and objective anterior cruciate tests. Twenty-seven chronic anterior cruciate ligament deficient knees reconstructed with the middle third of the patellar tendon and 28 chronic anterior cruciate ligament deficient knees reconstructed with the semitendinosus tendon were included in this consecutive group of patients and were felt to be directly comparable. It was found that the chronic an terior cruciate ligament deficient group reconstructed with the semitendinosus tendon had 4 excellent, 10 good, 7 poor, and 7 failures with an objective score averaging 4.5 of a possible 12, while the comparable group reconstructed with the middle third of the patellar tendon had 16 excellent, 7 good, 3 poor, and only 1 failure with a score of 10 of a possible 12 (P < 0.0032). For completeness sake, 20 anterior cruciate deficient knees from this group of consecutive patients that were reconstructed acutely with the semitendinosus tendon were also examined. This group had 8 excellent results, 9 good, 3 poor, and no failures with a score of 9.8 (P < 0.03 compared to the other group using the semiten dinosus tendon). This comparison between the two groups where the semitendinosus tendon was used in the anterior cruciate ligament reconstruction was made only to show the difference between studies dealing with knee reconstructions. There may be a significant difference between a study dealing with acutely recon structed knees versus one focusing on chronically re constructed knees, most likely because of both patient selection and time between injury and reconstruction. Subjectively, the activity forms gave postreconstruc tion activities of 112 of 200 for the chronically recon structed group using semitendinosus tendon, 115 for the chronically reconstructed group using the middle third of the patellar tendon, and 150 in the acutely reconstructed group using the semitendinosus tendon. The subjects rated their knee 6.2 (chronically recon structed with semitendinosus), 6.4 (chronically recon structed with middle third patellar tendon), and 7.9 (acutely reconstructed with semitendinosus) on a scale of 0 to 10.

This paper will point out the superiority of using the middle third of the patellar tendon over the use of the semitendinosus tendon in chronically unstable knees. The semitendinosus tendon should not be used even with extraarticular augmentations. The data for the semitendinosus tendon in acute anterior cruciate liga ment reconstruction is included to show how different two groups of patients can be based on the time of reconstruction from the date of injury.
Use of the fascia sheath coverage and exogenous fibrin clot in the treatment of complex meniscal tears
Authors: Henning Charles E. , Yearout Kim M. , Vequist Steven W. , Stallbaumer Robert J. , Decker Krista A.
Published: June 2007

In a previous series, complex meniscal tears, including double flap, double longitudinal, and radial tears, there was reported a high failure rate (14 of 58 repairs, 24%) when treated by conventional arthroscopic repair tech niques. There was only one tear in the anterior middle one-third of the lateral meniscus in this group. The use of a fascia sheath to cover the repaired area improves healing rates an additional 17% (from 75% to 92%) with these tear classifications, with the exception of radial split tears in the middle one-third of the lateral meniscus. The present repair technique includes rasp abrasion of the parameniscal synovium, peripheral white rim, and tear surface of the handle fragment. The meniscus is sutured with fully diverged sutures. A rec tangle of fascia from the distal anterolateral thigh, trimmed to 25 x 35 to 40 mm, is prepared with the double-armed meniscus suture run along opposite sides. One or two "hold-down" sutures are tied to the superior and inferior main sutures. The four hold-down sutures from the corners and the previously placed hold-down sutures are pulled through the capsule with previously placed pull-through sutures to pull the fascia over the meniscal repair. The exogenous blood clot is injected in the tear under the sheath. This preliminary report suggests that improved healing rates can be obtained with most complex tears by meticulous men iscal repair followed by coverage with the fascia sheath and then exogenous clot injection. Repairs of tears in the middle one-third of the lateral meniscus still show a high failure rate.
Traumatic pseudodislocation of the acromioclavicular joint in children
Authors: Black G. Brian , McPherson Jack A.M. , Reed Martin H.
Published: June 2007

Traumatic acromioclavicular separation in the skeletally immature patient is frequently overdiagnosed and overtreated. Fifty-eight children, aged 5 to 16 years, who presented over a 15 year period with injuries to the distal clavicle, were reviewed retrospectively. The majority showed coracoclavicular widening radiograph ically, suggesting acromioclavicular separation.

In 45 cases, a distal clavicular fracture was identified, while an acromioclavicular separation without fracture was initially diagnosed in 13.

Long-term followups of these patients demonstrate excellent results with conservative management. "Pseudodislocation" involves a clavicular fracture of the lateral metaphysis or metaphyseal epiphyseal separa tion and not an acromioclavicular disruption. This pseu dodislocation of the acromioclavicular joint in the skel etally immature patient must be differentiated from the adult counterpart to avoid unnecessary operative inter vention.
Reconstruction of chronic insufficient anterior cruciate ligament in the knee using a synthetic Dacron prosthesis
Authors: Andersen Henrik Nørholm , Bruun Carsten , Sønergåro-Petersen Poul Erik
Published: June 2007

In this study, a total of 57 patients with rupture of the anterior cruciate ligament and persistent functional in stability of the knee had their anterior cruciate ligament reconstructed with a Dacron prosthesis between No vember 1984 and February 1987. The patients, 43 males and 14 females with a mean age 26 years (range, 16 to 42), were followed for 2 to 4 years (mean, 34 months). In total, 30 patients had concomitant knee ligament or meniscal lesions. Postoperatively, the knee was not immobilized, but was actively trained in a cast brace.

At followup, 54 of the patients were examined, and 71% had a good or excellent result according to the Lysholm score. The Tegner activity score improved in 33 patients and 15 achieved their preinjury sporting activity level. The instability, as measured by the ante rior drawer sign and the Lachman test, declined from 3.3 to 2.1. Ten prostheses had ruptured at a mean of 11 months (range, 3 to 21). One patient had a deep postoperative infection, another developed chronic syn ovitis, and one incurred reflex dystrophic changes.
Functional knee braces increase intramuscular pressures in the anterior compartment of the leg
Authors: Styf Jorma R. , Nakhostine Manoutch , Gershuni David H.
Published: June 2007

The effect of three different functional knee braces on intramuscular pressures in the anterior compartment of the leg was investigated in 8 healthy subjects. Pres sures were recorded with the microcapillary infusion technique while the subjects were either supine, sitting, or standing. Pressures at rest in the anterior tibial muscle increased significantly following application of each of the three knee braces regardless of posture. Similarly, muscle relaxation pressure during exercise also increased significantly on brace application. A pres sure of 40 mm Hg was exceeded in 9 of 18 intramus cular pressure measurements with the subject stand ing. The tested functional knee braces increased mus cle pressures at rest and muscle relaxation pressure during exercise to levels that, according to other stud ies, might decrease muscle blood flow significantly. External compression from a knee brace on leg muscles might, therefore, induce premature muscle fatigue be cause of local insufficient perfusion of the working muscle.
Repair of rotator cuff tears in tennis players
Authors: Bigiliani Louis U. , Kimmel Jay , McCann Peter D. , Wolfe Ira
Published: June 2007

Twenty-three tennis players with a symptomatic full- thickness rotator cuff tear underwent anterior acro mioplasty and rotator cuff repair. There were 8 small tears (<1 cm), 5 moderate tears (1 to 3 cm), 2 large tears (3 to 5 cm), and 8 massive tears (>5 cm). The dominant shoulder was involved in all patients and all were unable to play tennis before surgery. Eleven pa tients experienced a traumatic event that caused an injury, 6 while playing tennis, and 12 patients had a gradual onset of symptoms. At average followup of 42 months, 19 patients (83%) achieved a good result, were pain-free, and were able to play tennis at their pre- symptomatic competitive level. Three patients (13%), all with massive tears, had a satisfactory result and were able to play tennis, although at a lower competitive level secondary to weakness. One patient (4%), who also had a massive tear, had an unsatisfactory result and was unable to play tennis.
Parameters and comparisons of the quadriceps angle of college-aged men and women in the supine and standing positions
Authors: Woodland Lynn H. , Francis Rulon S.
Published: June 2007

The purpose of this study was to determine normal, mean quadriceps angles (Q angles) for college-aged men and women, and to compare Q angles measured in the supine and the standing positions. The Q angles of 269 men and 257 women were measured in both positions by use of a specially modified goniometer. The mean Q angle for men was 12.7° in the supine position and 13.6° in the standing position; for women the mean Q angle was 15.8° in the supine position and 17.0° in the standing position. All of these differences were statistically significant. We calculated the inci dence of an abnormally high Q angle, and will discuss the implications of our findings.
Effect of shoe cushioning on the development of reticulocytosis in distance runners
Authors: Dressendorfer Rudolph H. , Wade Charles E. , Frederick Edward C.
Published: June 2007

We studied erythropoietic activity in relation to the rearfoot cushioning of shoes worn by 14 male runners before, during, and the morning after a 17-day period of increased training mileage. The percentage of retic ulocytes in the red blood cell count (normal, <0.8%) served as the marker for erythropoietic activity. Each runner was assigned to either a firm-sole group (7) or a soft-sole group (7) according to the heel impact attenuation character (Peak g) of his shoes. Peak g was 18% greater in the firm-sole group (P < 0.001). Otherwise, the groups were similar in physical charac teristics, training mileage, and running ability. All sub jects ran a total of 430 km, a distance that averaged 79% higher than their regular training distance for a 17- day period.

Resting blood samples were obtained at baseline and on three mornings (Days 11, 13, and Day 18, which followed the completion of the increased training period). No significant differences were found between the groups in red blood cell count, hematocrit, or total hemoglobin, haptoglobin, plasma-free hemoglobin, and serum ferritin levels. The groups did not differ in percent reticulocytes at baseline (0.2% firm-sole versus 0.2% soft-sole), on Day 11 after running 280 km (0.8% firm- sole versus 0.8% soft-sole), or on Day 13 after 48 hours of rest (1.3% firm-sole versus 1.0% soft-sole). However, on Day 18 after running 430 km, reticulocyte counts were 29% higher (P < 0.05) in firm-sole than soft-sole (2.2% versus 1.7%, respectively). The overall change in percent reticulocytes was linearly correlated with Peak g (r = 0.57, P < 0.05).

Although marked reticulocytosis occurred in both groups, it was significantly more pronounced in the firm-sole group. The positive correlation between per cent reticulocytes and Peak g suggests that shoe rear foot cushioning is one determinant of the erythropoietic response to increased training mileage in distance run ners.
The effect of tibial attachment site on graft impingement in an anterior cruciate ligament reconstruction
Authors: Yaru Nicholas C. , Daniel Dale M. , Penner Darrell
Published: June 2007

Anterior cruciate ligament reconstructions were per formed in 14 cadaveric knee specimens using a 6-mm wide polypropylene graft. The graft was passed through a femoral tunnel at the attachment site of the anterior medial bundle of the anterior cruciate ligament. Seven tibial positions were evaluated as to the change in attachment site distance with passive range of mo tion and impingement on the intercondylar notch as the knee was passively ranged from 0° to 90° of flexion. Impingement was also evaluated while the knee was extended by pulling through the quadriceps tendon. The tibial placement site affects the change in attach ment site distance with passive range of motion and impingement on the intercondylar notch. Grafts passed through drill holes anterior and lateral to the insertion of the anterior fibers of the anterior cruciate ligament consistently produced impingement on the anterior out let of the intercondylar notch. Knee extension with quadriceps tendon pull produced graft impingement in a greater arc of flexion than passive extension. Based on this study, optimum placement of the tibial hole should be at the insertion of the anterior medial fibers of the anterior cruciate ligament. Impingement recog nized during surgery can be alleviated with notchplasty. With passive extension there should be a 3-mm clear ance between the anterior portion of the intercondylar notch and the ligament graft to prevent the graft from impinging when the knee is actively extended.
Arthroscopic staple capsulorrhaphy for anterior shoulder instability
Authors: Coughlin Larry , Rubinovich Mitch , Johansson Joyce , White Brad , Greenspoon Jeffrey
Published: June 2007

We reviewed the results of the arthroscopic staple capsulorrhaphy on 47 patients with a followup of 4 years. Thirty-four of the 47 shoulders had a history of traumatic dislocation, while the remaining 13 had a history of subluxation. The recurrence rate was 25%, with 8 shoulders developing recurrent frank dislocation and 4 developing subluxation. Only 21 of the 47 pa tients were able to resume normal sporting activities after surgical repair. We had no cases of staple loos ening within the joint, but we did have 3 patients whose staples were removed because of persistent pain in the shoulder.
The effect of external ankle support in chronic lateral ankle joint instability
Authors: Karlsson Jon , Andreasson Gunnar O.
Published: June 2007

We examined the effect of ankle taping on ankle joint stability by measuring mechanical stability using stand ardized stress radiographs. Anterior talar translation and talar tilt, both with and without ankle tape, were examined. The reduction of anterior talar translation and talar tilt with tape as compared to without tape was insignificant.

The reaction time of the peroneus muscles was measured by electromyographic signal after a simulated ankle sprain on a tilting trapdoor. The reaction time was significantly slower in the unstable ankles of 20 athletes with unilateral ankle instability than in the stable contra lateral ankles. With tape, the reaction time was signifi cantly shortened, although not back to normal. The greatest improvement in reaction time was achieved in ankles with the highest degree of mechanical instability. Thus, the mechanism behind the function of ankle tape may be to restrict the extremes of ankle motion and to help shorten the reaction time of the peroneus muscles by affecting the proprioceptive function of the ankle.