bluuebunny/crossref_metadata_2025_split huggingface dataset:
An in vitro study of anterior cruciate ligament graft placement and isometry
Authors: Penner Darrell A. , Daniel Dale M. , Wood Peter , Mishra Dev 
Published: June 2007

Isometric positioning of the ACL graft or prosthesis is an important consideration in successful reconstruction of the ACL-deficient knee. This study documented the relationship between graft placement and intraarticular graft length changes and graft tension changes during knee passive range of motion. Fifteen fresh cadaveric knees were mounted in sta bilizing rigs. The ACL was identified and cut in each specimen. Intraarticular reconstruction was then per formed using a 6 mm polypropylene braid (3M LAD, St. Paul, MN). The following graft placements were evalu ated : 1) over-the-top, 2) modified over-the-top with a femoral bone trough, 3) femoral drill hole positions, and 4) tibial drill hole positions. The proximal end of the graft was fixed to the lateral aspect of the femur with a screw and spiked washer. The distal end of the graft was attached to a turnbuckle attached to a load cell on the anterior aspect of the tibia. The knee was then extended passively from 90° to 0°. Two experiments were performed. In Experiment A, the turnbuckle was adjusted to keep graft tension constant and the graft length changes were recorded. In Experiment B, the graft fixation sites were not altered and tension changes with range of motion were recorded. A change in the graft distance between attachment sites with knee range of motion can be monitored either by ligament length or by tension change. With the over- the-top technique, in Experiment A, the graft distance between attachment sites increased as the knee was extended (x = 4.9 mm); in Experiment B, large tension increases were recorded with knee extension. With the modified over-the-top technique with femoral bone trough, isometry was approached as the average length increase with knee extension was reduced to 1.0 mm (Experiment A) and minimal tension increases occurred (Experiment B). Femoral drill holes positioned postero superiorly on the lateral femoral condyle produced vari able length or tension increases with knee extension. Anteriorly positioned femoral drill holes produced sig nificant length decreases with knee extension in Exper iment A (x = -5.5 mm) while tension measurements showed loss of graft tension with knee extension (Ex periment B). Finally, tibial drill hole position was also found to be vital for proper isometric tracking. Tibial drill holes situated immediately anterior to the antero medial portion of the ACL insertional site yielded the best isometric placement for the femoral orientations tested. Care must be taken, however, that this tibial position does not cause impingement in the intercon dylar notch.
Computed tomography (CT) arthrography of shoulder instabilities in athletes
Authors: Raf Mahvash , Minkoff Jeffrey , Bonamo John , Firooznia Hossein , Jaffe Leonard , Golimbu Cornelia , Sherman Orrin 
Published: June 2007

Sixty professional and recreational athletes underwent CT arthrography of the shoulder for evaluation of sus pected shoulder joint derangement. These athletes, 46 males and 14 females ranging in age from 15 to 60 years (mean, 32 years), all had persistent pain that interfered with their sports activity and was resistant to conservative treatment. Seventeen patients had shoulder instability based on clinical manifestations and CT arthrographic findings. An additional five patients, also based on clinical mani festations and CT arthrographic findings, were consid ered to have an unobtrusive degree of anterior joint laxity. Patients with anterior instability (20 cases) all had an anteroinferior tear or detachment of the glenoid labrum, as well as some violation of the insertion of the joint capsule onto the scapula. Those with posterior instability (two cases) had a combination of labral and capsular tears. Two other major patterns of labral tears, both unaf filiated with shoulder instability, were identified. These included total or partial detachment of superior seg ments of the labrum, and anterior labral tears at the midglenoid level. Moreover, various degrees of labral attenuation (or, less often, enlargement), osteophyte formation, and alterations in articular cartilage were observed. Surgical correlation was obtained in 25 pa tients, with 95% accuracy of CT arthrographic findings. CT arthrography is a minimally invasive and highly accurate technique for investigation of glenohumeral derangement. Specifically, the extent of pathologic changes associated with instability can be determined and differentiated from other intraarticular causes of incapacity, such as labral tears caused by throwing, or degenerative changes.
Medial subluxation of the patella as a complication of lateral retinacular release
Authors: Hughston Jack C. , Deese Melvin 
Published: June 2007

We examined 54 patients (60 knees) referred to us because of their failure to improve, or because of a worsening of their preoperative symptoms, following an arthroscopic lateral retinacular release. Thirty knees developed medial subluxation of the patella postoper atively. This disabling condition is new to us. It is previously unreported as a complication of arthroscopic lateral retinacular release. Anterior knee pain was the only reported preoperative symptom in 14 knees. Six teen knees had a preoperative diagnosis of lateral patellar subluxation on the basis of a positive appre hension sign only. Eighteen of 30 knees had no surgery of the extensor mechanism other than the arthroscopic lateral release. The remainder additionally underwent varying types and numbers of operations in an attempt to resolve their disability. CAT scan evaluation of three patients who volun teered for the procedure demonstrated severe atrophy and retraction of the vastus lateralis. Loss of this dy namic lateral stabilizer contributed to the medial sub luxation of the patella.
Prevalence and types of injuries in aerobic dancers
Authors: Rothenberger Lee A. , Chang June I. , Cable Thomas A. 
Published: June 2007

A sample of 726 aerobic dancers was surveyed by questionnaire to document the prevalence, types, and severity of injuries experienced. Data were gathered on demographics, exercise behavior, and environmental conditions during a 1 week period. Most of the subjects (66%) engaged in aerobic dance classes at least every other day, with a mean exercise time of 195 minutes per week. Twenty-eight percent of the subjects had been exercising 1 to 2 years, and 26% had been exercising 2 years or longer. Forty-nine percent of the subjects reported a history of at least one injury related to aerobic dancing. Most of the injuries were to the shin (24.5%), lower back (12.9%), and ankle (12.2%). Among those subjects injured, 23% reportedly saw a physician because of their injury. The frequency with which subjects exer cised was associated with a history of injury. Subjects who exercised fewer than four times per week reported fewer injuries (43%) than those who exercised four times per week (60%) or more (66%). This study is a first step toward providing data to help physicians counsel aerobic dancers regarding in jury prevention.
The stabilizing effect of the ligamentous structures in the sinus and canalis tarsi on movements in the hindfoot
Authors: Kjærsgaard-Andersen Per , Wethelund Jon-Oddvar , Helmig Peter , Søballé Kjeld 
Published: June 2007

Three-plane kinesiology of hindfoot instability was stud ied after lesions to the ligamentous structures in the sinus and canalis tarsi in 20 amputation specimens. Neither a lesion of the cervical ligament nor of the interosseous talocalcaneal ligament resulted in an in crease in the total range of movements above 2.6° in any of the three planes. However, the percentage in crease in the total range of movements after cutting of the ligaments was generally largest in the talocalcaneal joint compared to the increase in the total hindfoot joint complex. The largest percentage increase (43%) in the talocalcaneal joint occurred at dorsiflexion after cutting the interosseous talocalcaneal ligament. The demonstrated minor instability after experimental lesions of the ligamentous structures in the sinus and canalis tarsi may have a clinical identity in the sinus tarsi syndrome. Patients with that syndrome rarely present an objective hindfoot instability, although a major complaint is a feeling of hindfoot instability.
The results of operative treatment of osteochondritis dissecans of the patella
Authors: Schwarz Charles , Blazina Martin E. , Sisto Domenick J. , Hirsh Linda C. 
Published: June 2007

The course of osteochondritis dissecans (OCD) of the patella and the results of operative treatment are ana lyzed retrospectively in a review of 31 operatively treated cases in 25 patients. Followup was obtained for 21 cases, with an average of 73 months (range, 15 months to 20 years). These 25 patients were predom inantly males, and averaged 18 years of age at the time of surgery. A history of trauma was associated with the lesion in 38% of the cases, and the lesion was bilateral in one out of four patients. The most common present ing complaints were subpatellar pain and swelling. The most common initial physical findings were patellofem oral crepitus and joint effusion. Forty-four operations were performed on 31 knees. The most commonly performed procedures were cu rettage of the patella and removal of loose bodies, in combination or as part of another procedure. A new patellofemoral rating scale was used to evaluate re sults. Thirty-eight percent of the knees had a good or excellent result, while 62% had a fair or poor result. Persistent pain with restricted function and residual patellofemoral crepitus were common findings. In general, the patients who come to surgery for OCD of the patella have a guarded prognosis for full recovery of knee function.
Operative ankle arthroscopy
Authors: Martin David F. , Baker Champ L. , Curl Walton W. , Andrews James R. , Robie David B. , Haas Albert F. 
Published: June 2007

Ankle arthroscopy has become an accepted procedure for the treatment of various intraarticular disorders. More than 100 ankle arthroscopies have been per formed at our institution since 1983. To better define the role of arthroscopic surgery in the treatment of ankle disorders, we evaluated the preoperative exami nation and indications, operative data, and radiographs of those patients with a minimum of 1 year of followup. Fifty-eight ankles in 57 patients were identified; their average follow-up period was 25 months (range, 12 to 49 months). Preoperative diagnoses were synovitis (26), trans chondral defects of the talus (17), degenerative joint disease (8), and osteophytes or loose bodies (7). Sub jective results were good or excellent in 64% of cases. The best overall results were achieved in patients with synovitis (77%) and transchondral defects of the talus (71 %). Degenerative joint disease patients did not do well. They had only 12% good or excellent results and a 43% rate of subsequent fusion. Complications in cluded superficial and deep infections, temporary and permanent paresthesias, and hemarthroses; the overall complication rate was 15%. In conclusion, operative ankle arthroscopy can be useful in selected patients. It is an effective surgical procedure in patients with synovitis and transchondral defects of the talus. The benefits and long-term results are less predictable with loose bodies and impinging osteophytes; the results are poor with degenerative joint disease. There appears to be a significant risk of complication with ankle arthroscopy; however, with proper indications, a thorough knowledge of anatomical landmarks, and meticulous technique, good results can be obtained.
Early experience with the GORE-TEX polytetrafluoroethylene anterior cruciate ligament prosthesis
Authors: Indelicato Peter A. , Pascale Mark S. , Huegel Marty O. 
Published: June 2007

A prospective study of 41 patients with acute and chronic ACL deficiency underwent reconstruction with the GORE-TEX polytetrafluoroethylene (PTFE) ACL prosthesis beginning in November 1983. Thirty-nine patients who were at least 2 years from their surgical procedure were available for follow-up evaluation, which included subjective questionnaire, clinical exam ination, and instrumented ligamentous laxity tests. Eight patients had an acute injury to the ACL and 31 patients had chronic ACL insufficiency for which recon struction was performed. Thirty-four patients had satisfactory results, allowing full return to activity with no appreciable symptomatol ogy. Of the remaining five patients, four had a complete rupture of the prosthesis. The average knee arthrome tric measurement improved from a 5.4 mm left/right difference preoperatively to a 2.0 mm left/right differ ence at 2 year followup. Nine patients had postopera tive complications of one or more atraumatic episodes of a sterile effusion. Six patients had recurrent effu sions ; in five, arthroscopy revealed partial tears of less than one-third of the prosthesis. Three patients who had recurrent effusions had PTFE particles in their synovial biopsies. One patient had an immediate post operative infection and to date has had salvage of the prosthesis and currently has a stable knee with full return to activities. Based on the early results of this study, the GORE- TEX PTFE ACL prosthesis provided a satisfactory method of reconstruction for ACL deficient knees. Based on the evaluation used, 87% of the patients had satisfactory results. Problems associated with use of this prosthesis include partial or complete tears of the prosthesis and sterile effusions, possibly due to syno vial irritation from the PTFE particles. Appropriate placement of the graft, anterior and posterior notch plasty, and removal of sharp edges from the bony tunnels may help eliminate these problems.
Healed meniscal tears in unstable knees
Authors: Sommerlath Karola , Hamberg Per 
Published: June 2007

Peripheral vertical ruptures of the medial (N = 24) and the lateral (N = 4) meniscus were repaired in 28 patients (mean age, 27 years). They all had an ACL lesion, combined in 26 cases with a MCL tear. These injuries were reconstructed or sutured during the same session as the meniscus repairs. Approximately 1 year later, meniscal healing was proven arthroscopically in 20 and the other 8 had no clinical signs of meniscal rerupture. All patients were reexamined between 6 to 8 years after the initial repair. Instrumented stability testing, the Lysholm knee function score and an activity score (Tegner) were used. The patients' subjective evalua tions were also recorded. In spite of the previous reconstruction, all knees were quite unstable (mean +5 mm increased laxity compared with the uninjured side). At followup, 3 of the 28 re paired menisci (11%) had reruptured in connection with a minor trauma during sports or daily activity. The knee function score averaged 88 points, the activity level dropped 2 steps compared with activities before injury (from 7 to 5). Twenty patients were satisfied with the results, 5 partly satisfied, and 3 not satisfied. A healed meniscal tear has a good chance of survival in an unstable knee. The most critical period of meniscal repair probably lies in the healing period just after surgery.
Factors affecting the region of most isometric femoral attachments
Authors: Hefzy Mohamed S. , Grood Edward S. , Noyes Frank R. 
Published: June 2007

During flexion of the intact knee, we measured the changes in distance between possible tibial and femoral attachments of an intraarticular ACL substitute. The change in distance during motion was described by the difference between the longest and shortest distances measured. Using knees from eight cadaver donors, we studied the effects of varying tibial and femoral attach ment locations, applying anterior and posterior forces, and altering the range of flexion. We found that altering the femoral attachment had a much larger effect than had altering the tibial attach ment. No femoral attachments were completely iso metric. Femoral attachments that produced the small est change in tibiofemoral distance, 2 mm and less, formed a band whose greatest width ranged from 3 to 5 mm. The axis of the 2 mm region was nearly proximal- distal in orientation and located near the center of the ACL's femoral insertion. Attachments located anterior to the axis moved away from the tibial attachment with flexion, whereas attachments located posterior to the axis moved toward the tibia. The AP position of the tibial attachment affected the orientation of the 2 mm region. Moving the tibial attach ment posteriorly caused the proximal part of the region to move anterior, with little change in the location of the distal part of the region. Changing the applied joint force from anterior to posterior was similar to moving the tibial attachment posteriorly, but the effect was less pronounced. Increasing the range of flexion from 90° to 120° caused the 2 mm region to become narrower and changed its orientation.
Augmentation with the longitudinal patellar retinaculum in the repair of an anterior cruciate ligament rupture
Authors: Jonsson Torsten , Peterson Lars , Renström Per , Althoff BO , Myrhage Ragnar 
Published: June 2007

Most authors advocate repair of the acutely ruptured ACL by augmentation or some form of primary recon struction. Strong autogenous tissues like the patellar and semitendinosus tendons and the iliotibial band are often used when augmentation is the surgical choice. This paper describes a surgical procedure using a strip of the longitudinal patellar retinaculum as an aug mentation of the repaired ACL. The retinaculum adds stability and strength to the repaired ACL during the healing period. Moreover, the retinaculum may enhance the healing process of the ruptured ACL by revascular ization. It may also increase the stimulation of synovial tissue proliferation over the repaired ACL. Twenty-eight patients have been clinically and objec tively evaluated at a mean follow-up time of 78 months (range, 63 to 94 months). The patients' own evaluation of their knee function was excellent or good in 86% (24 patients). Eighty-two percent (23 patients) could return to their preinjury activities at the same intensity level as before injury, whereas at an intermediate followup at 18 months only 64% (18 patients) had done so. Anterior tibial displacement was objectively evaluated at both followups by means of the anterior drawer test, with 20° to 30° and 90° of knee flexion, in a testing device. The operated knee usually showed a tendency to a slightly increased anterior displacement when com pared with the uninjured knee. The repair of a ruptured ACL with an augmentation using the longitudinal patellar retinaculum has been shown to give good results after more than 5 years.
Fluid and electrolyte balance during a cool weather marathon
Authors: Nelson Paul B. , Ellis David , Fu Freddie , Bloom Marie D. , O'Malley Jean 
Published: June 2007

Changes in blood, serum, and urine parameters that are usually associated with fluid and electrolyte balance were studied in 45 volunteers who ran the 1987 Pitts burgh Marathon. There were 39 males and 6 females. The mean age was 39.3 years. Their mean fluid intake was 1650 cc and the mean finishing time was 4 hours and 1 minute. The race was run in the rain with a temperature of 46°F. When the prerace and postrace values of the runners were compared, significant increases were noted in the serum sodium, potassium, blood urea nitrogen (BUN), creatinine, uric acid, creatine phosphokinase (CPK), protein, plasma renin, vasopressin, and urinary potas sium. Significant decreases were found in weight, blood pressure, and urinary sodium. No significant differences were noted in serum chloride, serum glucose, and hemoglobin/hematocrit. The mean weight loss of 1.9 kg was less than weight losses reported in marathons run under warmer conditions.
The use of magnetic resonance imaging in exertional compartment syndromes
Authors: Amendola A. , Rorabeck C.H. , Vellett D. , Vezina W. , Rutt B. , Nott Linda 
Published: June 2007

This prospective, double-blind study was carried out to assess the usefulness of magnetic resonance imaging (MRI) as a noninvasive method in the diagnosis of chronic compartment syndrome (CCS). As well, a new radiopharmaceutical known as methoxy isobutyl isoni trile that has been shown to be taken up by muscle in direct proportion to its blood flow was used to illustrate the possible pathophysiology of this syndrome. Twenty patients with a history of chronic leg pain and possible diagnosis of CCS and five normal volunteers had preexercise and postexercise MRI, nuclear medi cine imaging, and static and dynamic slit catheter pres sure studies. Nine patients had classic symptoms; only five of these nine had abnormal pressure studies. The other 11 patients had an element of pain at rest and had normal pressure studies. The nuclear blood flow studies were normal in all 25 legs tested in this study. Measurement of intrinsic MRI parameters T1 and T2 in the normal legs as well as in those with an atypical history showed a marked elevation with exercise and a gradual return to baseline postexercise that was similar to the pres sure curves. In the five patients with a clinical history and elevated pressures, four had abnormal MRI studies with failure of T1 to return to baseline values. Although these results demonstrate the potential of MRI as a tool for noninvasively monitoring muscle sta tus, clinical history and examination remain important in the diagnosis of CCS. This study indicates that the pathophysiology of exertional compartment syndrome does not appear to be related to ischemia.
A nonparallel, nonisometric synthetic graft augmentation of a patellar tendon anterior cruciate ligament reconstruction
Authors: McCarthy Jack A. , Steadman J. Richard , Dunlap Janet , Shively Robert , Stonebrook Scott 
Published: June 2007

The potential for a rigidly fixed synthetic graft placed in the over-the-top position to be stress shielding/stress sharing with the patellar tendon autograft was as sessed in a primate model. A patellar tendon autograft was placed anatomically and tensioned at 2 pounds for all of the groups. In the augmented animals, a 30 strand braided graft 10 cm in length of expanded polytetra fluoroethylene was tightened with the knee in full ex tension. After 6 months of unrestricted cage activity the animals were sacrificed and biomechanical testing performed. The augmented patellar tendon autografts demonstrated less laxity in extension as compared to the autografts alone. A minimal decrease in the load and stiffness to failure for the augmented groups as compared to the nonaugmented knees was noted. However, both the reconstruction groups had a signif icant decrease in the load to failure at 6 months (50% of the normal ACL). In summary, this study demonstrated that a synthetic graft augmentation can be performed in the over-the- top position and minimize knee laxity, especially during terminal extension. With this technique, the laxity was minimized while the incorporation and strengthening of the biologic autograft occurred at a rate similar to the unaugmented reconstruction.