bluuebunny/crossref_metadata_2025_split huggingface dataset:
Initial Fixation Strength of Two Bioabsorbable Pins for the Fixation of Hamstring Grafts Compared to Interference Screw Fixation
Authors: Zantop Thore , Weimann Andre , Rümmler Markus , Hassenpflug Joachim , Petersen Wolf 
Published: March 2004

Background During the early postoperative period, the fixation of a hamstring graft to the bone tunnel is the primary factor in limiting rehabilitation. Hypothesis The initial fixation strength of a double cross pin fixation technique is comparable with the biodegradable interference screw fixation technique. Study Design Experimental laboratory study. Methods The authors examined the initial fixation strength of two 3.3-mm bioabsorbable pins compared to interference screws for hamstring grafts in bovine knees. Results Analysis of yield load, maximum load, and stiffness in the single-cycle loading test showed no statistically significant differences for cross pin and interference fixation (P< .05). For cross pins and interference screws, the mean displacement under 1000 cycles to 250 N was 5.07 (±1.9) mm and 4.81 (±2.5) mm, stiffness 252 (±78) N/mm and 289 (±148) N/mm. Only grafts fixed with cross pins survived 1000 cycles to 450 N. Conclusion The initial fixation strength of the double cross pin technique is comparable to that of interference screw fixation with a stiffness comparable to that of the native ACL. Clinical Relevance Hamstring graft fixation using two cross pins provides an alternative to bioabsorbable interference screw fixation.
Prospective Evaluation of 1485 Meniscal Tear Patterns in Patients with Stable Knees
Authors: Metcalf Michael H. , Barrett Gene R. 
Published: March 2004

Background Despite emphasis on classifying meniscal tears based on healing potential of the tear, research has concentrated on unstable knees, and few reports have provided information regarding associated clinical variables in stable knees. Purpose To report on a large series of meniscal tears in stable knees that have been carefully mapped by tear shape and tear zones to allow comparison with meniscal tears in unstable knees. Study Design Prospective case series, reviewed retrospectively. Methods A total of 1485 meniscal tears in stable knees were evaluated. Preoperatively, each patient underwent a standardized assessment. Each tear was carefully mapped at arthroscopy. Statistical analysis was performed to determine factors that may be associated with peripheral meniscal tears. Results The distribution and shape of tears varied significantly within the radial and circumferential zones in this stable knee population. Five prospective variables were associated with peripheral tears: gender, presence of an effusion, positive McMurray test, varus alignment, or a loss of extension more than 5°. Conclusions Patient demographic information and physical examination can be useful in identifying patients who may have a peripheral meniscus tear.
Mechanical Effects of Autogenous Osteochondral Surgical Grafting Procedures and Instrumentation on Grafts of Articular Cartilage
Authors: Kuroki Hiroshi , Nakagawa Yasuaki , Mori Koji , Ikeuchi Ken , Nakamura Takashi 
Published: March 2004

Purpose To analyze the mechanical effects of autogenous osteochondral grafting procedures on articular cartilage. Methods The intensity, duration, and interval (indexes of stiffness, surface irregularity, and thickness) of the cartilage were assessed in a porcine model using an ultrasonic measurement system. In 7 of 12 knees, 6-mm-diameter plugs were harvested from the donor knees and grafted into 5-mm recipient holes at 3 different points per knee (21 plugs). In the remaining 5 knees, 5-mm plugs were harvested and returned to their original position (28 plugs). Results No significant differences in the intensity, duration, and interval of the cartilage were observed with the plugs before harvesting and after grafting by the paired ttest. The 3 indexes of the 6- and 5-mm plugs that were grafted correlated significantly with those before they were. Conclusions These results suggest that osteochondral graft surgery does not affect the stiffness, surface irregularity, and thickness of the cartilage of the plugs at time zero.
Comparison of Shoulder Stabilization Using Arthroscopic Transglenoid Sutures versus Open Capsulolabral Repairs
Authors: Hubbell John D. , Ahmad Sohail , Bezenoff Leigh S. , Fond Jason , Pettrone Frank A. 
Published: March 2004

Background Few long-term studies have compared the efficacy of shoulder stabilization using arthroscopic or open procedures. Purpose To directly compare the outcomes of shoulder stabilization using arthroscopic transglenoid sutures versus open capsulolabral repairs. Study Design Uncontrolled retrospective review. Methods Fifty patients (30 arthroscopic and 20 open) were followed for a minimum of 5 years (mean, 68 months). Pain, motion, strength, function, stability, patient satisfaction, radiographs, and ability to return to preinjury activity levels were evaluated. Results The arthroscopic group had a 17% (5 of 30) dislocation rate and a 60% (18 of 30) rate of instability. Sixty-seven percent (6 of 9) of patients participating in collision sports had repeat instability. Eight of 18 patients with instability required open repair for persistent symptoms. There were no limitations of motion following arthroscopic stabilization. The open group had no episodes of dislocations or instability. Forty-five percent (9 of 20) had some loss of external rotation (range, 10°-40°) with a mean loss of 18. The one failure in this group had a 40° loss of external rotation and difficulty with recreational activity. No patients participating in collision sports had repeat instability. Conclusion We recommend open stabilization for patients participating in collision sports (for example, football, wrestling) or activities where better stability is required. For those participating in sports where performance may be compromised by loss of external rotation (such as swimming), newer arthroscopic techniques are recommended.
A Biomechanical Comparison of Repair Techniques for Type II SLAP Lesions
Authors: DiRaimondo Carl A. , Alexander Jerry W. , Noble Philip C. , Lowe Walter R. , Lintner David M. 
Published: March 2004

Background Multiple options exist for repair of superior labral tears. Purpose To compare commonly used fixation techniques for superior labral tears. Study Design Biomechanical cadaveric study. Methods A comparison of the initial strengths of fixation for type II superior labral anterior posterior (SLAP) lesions was performed in three cadaveric shoulder groups, each containing seven specimens. Two groups were repaired with screw-in anchors; one group had vertical sutures, the other horizontal. Group 3 was repaired using bioabsorbable tacks. Cyclic traction was applied to the biceps tendon. Repair failure (2 mm of permanent displacement) and ultimate failure were measured. Results Specimen stiffness was similar between groups. The mean load to repair failure was 123 ± 17 N in group 1, 114 ± 11 N in group 2, and 95 ± 13 N in group 3. The mean load to ultimate failure was 163 ± 15 N, 161 ± 12 N, and 145 ± 12 N, respectively. Although the repair failure loads of groups 1 and 2 were 29% and 17%, respectively, greater than the tack group, the differences were not statistically significant (P> .05). All ultimate failures occurred at the labral-implant interface. Conclusion Initial fixation strength of tissue tack and suture anchor repairs of SLAP lesions are comparable.
Tibiofemoral Kinematics of the Anterior Cruciate Ligament (ACL)-Deficient Weightbearing, Living Knee Employing Vertical Access Open “Interventional” Multiple Resonance Imaging
Authors: Logan Martin , Dunstan Edward , Robinson James , Williams Andrew , Gedroyc Wady , Freeman Michael 
Published: March 2004

Background Our current understanding of tibiofemoral kinematics in the anterior cruciate ligament (ACL)-deficient knee is very limited. Using vertical open-access MRI, it is possible to accurately analyze tibiofemoral motion in patients with isolated rupture of the ACL. Study Prospective cohort study. Purpose To assess if ACL rupture alters normal knee weightbearing kinematics. Methods Tibiofemoral motion was assessed through the arc of flexion from 0 ° to 90 ° in 10 patients with isolated rupture of the ACL in one knee and a normal contralateral knee. Midmedial and midlateral sagittal images were analyzed in all positions of flexion in both knees to assess the tibiofemoral relationship. Results In the lateral compartment of the knee, the tibial plateau is persistently subluxed anteriorly throughout the arc of flexion from 0 ° to 90 ° (flexion facet center to posterior tibial cortex distance of 15.8 mm ± 2.9 in ACL-deficient knees compared to 21.4 mm ± 1.4 in normal knees at 0 ° extension, P< .0001) when compared to normal knees. The medial tibiofemoral relationship is unchanged compared to normal knees. Conclusion Rupture of the ACL changes tibiofemoral kinematics producing anterior subluxation of the lateral tibial plateau. Clinical Significance Altered kinematics may explain, at least in part, the increased incidence of secondary osteoarthritis in patients with ACL rupture.
The Incidence and Risk Factors in the Development of Medial Tibial Stress Syndrome among Naval Recruits
Authors: Yates Ben , White Shaun 
Published: March 2004

Purpose To identify the incidence of medial tibial stress syndrome (MTSS) in a group of naval recruits undergoing a 10-week basic training period and to determine potential risk factors. Method One hundred and twenty-four recruits (84 men and 40 women) were followed prospectively during basic training. Anthropometric and lower limb biomechanical data were recorded at the start of the program along with injury history and previous sporting activity for the 3 months prior to enlisting. Recruits were monitored during training for development of medial tibial strees syndrome and were asked to complete an exit interview at the end of the program. Results Forty recruits (22 men and 18 women) developed medial tibial stress syndrome, giving an incidence of 35%. A significant relationship existed between gender and medial tibial stress syndrome (P= .012), with female recruits more likely to develop medial tibial stress syndrome than male recruits (53% vs 28%). A risk estimate revealed a relative risk of 2.03. The biomechanical results indicated a more pronated foot type (P= .002) in the medial tibial stress syndrome group when compared to the control group. A risk estimate established that recruits with a more pronated foot type had a relative risk of 1.70. Conclusion Identifying a pronated foot type prior to training may help reduce the incidence of medial tibial stress syndrome by early intervention to control abnormal pronation. Findings of a higher incidence of medial tibial stress syndrome among female recruits require further investigation.
Temperature Requirements for Altering the Morphology of Osteoarthritic and Nonarthritic Articular Cartilage
Authors: Kaplan Lee D. , Ionescu Dan , Ernsthausen John M. , Bradley James P. , Fu Freddie H. , Farkas Daniel L. 
Published: March 2004

Background Radiofrequency and laser thermal chondroplasty procedures are performed to debride and smooth fibrillated, articular cartilage. Hypothesis Temperature requirements necessary to achieve morphological change will be lower in fibrillated arthritic cartilage as compared with nonarthritic articular cartilage. Study Design Controlled laboratory study. Methods A thermal cell-culture chamber was mounted on a stereoscopic microscope and coordinated with a custom temperature-control program. Nonarthritic and osteoarthritic articular cartilage specimens were sectioned into full-thickness slices. The articular sections were exposed to temperatures incrementally from 37°C to 75°C. Real-time, digital capture microscopy was used to visualize and analyze the morphological changes undergone by the articular cartilage specimens. Results Arthritic articular cartilage displayed morphological change at 56.5 ± 1.7°C. Loss of fibrillation was the initial morphological change visualized. Continued thermal exposure caused a shrinkage effect of the entire tissue section that was similar to the change seen in nonarthritic sections. Nonarthritic cartilage displayed morphological change at 60.9 ± 1.9°C. Conclusions Consistent characteristic morphological changes were found at distinct temperatures in osteoarthritic and nonarthritic articular cartilage. Clinical Relevance This information begins to establish the thermal parameters required for morphological change of osteoarthritic articular cartilage.
Kinematic MRI Assessment of McConnell Taping before and after Exercise
Authors: Pfeiffer Ronald P. , DeBeliso Mark , Shea Kevin G. , Kelley Lorrie , Irmischer Bobbie , Harris Chad 
Published: March 2004

Background The authors assessed the effectiveness of McConnell medial glide taping after exercise using an MRI extremity scanner. Hypothesis McConnell taping would not be effective in maintaining medial glide of the patella after exercise. Methods Eighteen healthy women (mean age 22.28 ± 2.02 years) participated in the study. The patellofemoral joint was imaged at 4 knee flexion angles (0°, 12°, 24°, and 36°) in 3 conditions (no tape, with McConnell taping–medial glide, and with tape after exercise). Effectiveness was determined by measuring lateral patellar displacement. ANOVA and post hoc paired ttests were used to test for changes in lateral patellar displacement at each knee angle and condition. Results Statistical analysis revealed significant differences in lateral patellar displacement at all test angles, between the tape and no tape and between tape and tape after exercise conditions. Conclusions McConnell medial glide taping resulted in significant medial glide of the patellofemoral joint at all 4 knee angles before but not after exercise. However, McConnell medial glide taping may be effective under controlled rehabilitation conditions in which exercise is less intense. Clinical Relevance Beneficial effects of McConnell medial glide taping may be related to factors other than altered patellar alignment.
Automated External Defibrillators in National Collegiate Athletic Association Division I Athletics
Authors: Coris Eric E. , Sahebzamani Frances , Walz Steve , Ramirez Arnold M. 
Published: March 2004

Background Sudden cardiac death is the leading cause of death in athletes. Evidence on current sudden cardiac death prevention through preparticipation history, physicals, and noninvasive cardiovascular diagnostics has demonstrated a low sensitivity for detection of athletes at high risk of sudden cardiac death. Data are lacking on automated external defibrillator programs specifically initiated to respond to rare dysrhythmia in younger, relatively low-risk populations. Methods Surveys were mailed to the head athletic trainers of all National Collegiate Athletic Association Division I athletics programs listed in the National Athletic Trainers’ Association directory. In all, 303 surveys were mailed; 186 departments (61%) responded. Results Seventy-two percent (133) of responding National Collegiate Athletic Association Division I athletics programs have access to automated external defibrillator units; 54% (101) own their units. Proven medical benefit (55%), concern for liability (51%), and affordability (29%) ranked highest in frequency of reasons for automated external defibrillator purchase. Unit cost (odds ratio = 1.01; 95% confidence interval, 1.01-1.0), donated units (odds ratio = 1.92; confidence interval, 3.66-1.01), institution size (odds ratio = .0001; confidence interval, 1.3 E-4 to 2.2E-05), and proven medical benefit of automated external defibrillators (odds ratio = 24; confidence interval, 72-8.1) were the most significant predictors of departmental defibrillator ownership. Emergency medical service response time and sudden cardiac death event history were not significantly predictive of departmental defibrillator ownership. The majority of automated external defibrillator interventions occurred on nonathletes. Conclusions Many athletics medicine programs are obtaining automated external defibrillators without apparent criteria for determination of need. Usage and maintenance policies vary widely among departments with unit ownership or access. Programs need to approach the issue of unit acquisition and implementation with knowledge of the surrounding emergency medical service system, geography of their individual sports medicine facilities, numbers and relative risk of their athletes, and budgetary constraints.
Repetitive Low-Energy Shock Wave Treatment for Chronic Lateral Epicondylitis in Tennis Players
Authors: Rompe Jan D. , Decking Jens , Schoellner Carsten , Theis Christoph 
Published: March 2004

Background There is conflicting evidence regarding extracorporeal shock wave treatment for chronic tennis elbow. Hypothesis Treatment with repetitive low-energy extracorporeal shock wave treatment is superior to repetitive placebo extracorporeal shock wave treatment. Methods Seventy-eight patients enrolled in a placebo-controlled trial. All patients were tennis players with recalcitrant MRIconfirmed tennis elbow of at least 12 months’ duration. Patients were randomly assigned to receive either active low-energy extracorporeal shock wave treatment given weekly for 3 weeks (treatment group 1) or an identical placebo extracorporeal shock wave treatment (sham group 2). Main outcome measure was pain during resisted wrist extension at 3 months; secondary measures were >50% reduction of pain andthe Upper Extremity Function Scale. Results At 3 months, there was a significantly higher improvement in pain during resisted wrist extension in group 1 than in group 2 (mean [SD] improvement, 3.5 [2.0] and 2.0 [1.9]; P= .001 for between-group difference of improvement) and in the Upper Extremity Function Scale (mean [SD] improvement, 23.4 [14.8] and 10.9 [14.9]; P< .001 for between-group difference of improvement). In the treatment group, 65% of patients achieved at least a 50% reduction of pain, compared with 28% of patients in the sham group (P= .001 for between-group difference). Conclusion Low-energy extracorporeal shock wave treatment as applied is superior to sham treatment for tennis elbow.
Does Immobilization after Radiofrequency-Induced Shrinkage Influence the Biomechanical Properties of Collagenous Tissue?
Authors: Pötzl Wolfgang , Heusner Till , Kümpers Philipp , Marquardt Björn , Steinbeck Jörn 
Published: March 2004

Background Despite widespread use of radiofrequency-induced shrinkage of collagenous tissue, there have been no animal studies on the effects of postoperative immobilization on the biomechanical behavior of shrunken tissue. Purpose To examine the role of postoperative immobilization after radiofrequency-induced shrinkage, with special emphasis on the biomechanical properties of shrunken collagenous tissue. Study Design Controlled laboratory study. Methods One patellar tendon of 66 New Zealand White rabbits was shrunk. Six rabbits were sacrificed immediately after surgery. Twenty rabbits were not immobilized, twenty were immobilized for 3 weeks, and twenty were immobilized for 6 weeks. The biomechanical parameters failure strength, stiffness, and relaxation were tested. Results Nine weeks after surgery, biomechanical parameters were still low compared to control tendons. Shrunken tendons did not reach levels of normal tissue at any time after surgery, regardless of whether the animals had been immobilized. According to time-related development, all biomechanical parameters had the lowest levels 3 weeks after surgery. Immobilized tendons demonstrated a better and faster recovery than nonimmobilized tendons compared to the immediate postoperative level. Conclusion Postoperative immobilization supports recovery of biomechanical properties after shrinkage. Despite immobilization, biomechanical properties of shrunken tissue did not completely reach levels of normal tissue. Clinical Relevance Careful rehabilitation is imperative after radiofrequency-induced shrinkage. This animal model supports an immobilization period of at least 6 weeks after surgery.
Mechanical Properties of Soft Tissue Femoral Fixation Devices for Anterior Cruciate Ligament Reconstruction
Authors: Ahmad Christopher S. , Gardner Thomas R. , Groh Megan , Arnouk Johnny , Levine William N. 
Published: March 2004

Purpose To evaluate femoral soft tissue fixation for anterior cruciate ligament reconstruction. Hypothesis Femoral fixation devices have different ultimate strengths and slippage under cyclic loading. Study Design Controlled laboratory study. Methods Thirty-three porcine femora were used to study interference screw (9), Endobutton (8), Rigidfix cross-pin (8), and Bio-Transfix cross-pin (8) fixation methods. Fixation slippage was evaluated under cyclical load from 50 N to 250 N using a materials testing machine. Ultimate load was determined with a single load to failure. Results Total graft slippage was greater (P< .001) for the Rigidfix (6.02 ± 2.12 mm) and the interference screw (5.44 ± 3.25 mm) compared to the Endobutton (1.75 ± 0.97 mm) and the Bio-Transfix (1.14 ± 0.53 mm). All techniques showed the greatest slippage during the first 100 cycles (Rigidfix 84%, Endobutton 70%, interference screw 56%, and Bio-Transfix 55%). The failure load for the interference screw technique (539 ± 114 N) was lower (P= .0008) than for the other 3 techniques (737 ± 140 N for Rigidfix, 746 ± 119 N for Bio-Transfix, and 864 ± 164 N for Endobutton). Conclusions The interference screw and the Rigidfix fixation demonstrated inferior fixation biomechanics compared to the Bio-Transfix and the Endobutton techniques.
Foam-Reinforced Elderly Human Tibia Approximates Young Human Tibia Better than Porcine Tibia
Authors: Bailey Shana B. , Grover Dustin M. , Howell Stephen M. , Hull Maury L. 
Published: March 2004

Background Because there is an insufficient supply of young human knees, an alternative is needed for evaluating anterior cruciate ligament reconstructions. The authors determined whether an elderly human tibia reinforced with foam is a better substitute for a young human tibia than a porcine tibia in this study of the tibial fixation of a soft tissue anterior cruciate ligament graft using 3 devices. Hypothesis A foam-reinforced elderly human tibia more closely approximates the performance of a young human tibia than a porcine tibia. Study Design Biomechanical study. Methods Failure mode, stiffness, yield, and slippage were determined for a double-looped tendon graft fixed with either an interference screw, WasherLoc, or tandem washers in young human tibiae, foam-reinforced tibiae from elderly humans, and porcine tibiae. Results The stiffness and yield of interference screw and WasherLoc fixation in foam-reinforced tibiae more closely approximate those in young human tibiae than in porcine tibiae. Slippage of all combinations of tibiae and fixation devices was similar. Conclusions A foam-reinforced human tibia more closely approximates the performance of a young human tibia than that of a porcine tibia in this study. Clinical Relevance Fixation devices should be tested in foam-reinforced tibiae from elderly humans rather than tibiae from large farm animals when the supply of young human knees is insufficient.