bluuebunny/crossref_metadata_2025 huggingface dataset:
Long-term study of anterior cruciate ligament reconstruction for chronic instability using the central one-third patellar tendon and a lateral extraarticular tenodesis
Authors: Aglietti Paolo , Buzzi Roberto , D'Andria Simone , Zaccherotti Giovanni
Published: June 2007

Forty-four patients with symptomatic chronic anterior cruciate ligament instabilities that had been recon structed with the central one-third patellar tendon and a lateral extraarticular iliotibial band tenodesis were studied at an average followup of 7 years (range, 4 to 10). The cases with associated medial, lateral, or pos terior laxity were not included, nor were the cases with more than minimal preoperative degenerative changes. The average age at surgery was 21 years (range, 16 to 33). A postoperative cast was used for 4 weeks.

Satisfactory objective stability, which was defined as a KT-1000 side-to-side difference of up to 5 mm at the manual maximum test, was obtained in 37 (84%) of the patients. In 25 patients (57%), stability was restored within normal limits (≤3 mm). No deterioration of the KT-1000 stability was noted at two follow-up visits performed by the same examiner (at an average of 4 and 7 years). A return to high-risk sports was possible in 27 (62%) of the patients.

Difficulties in regaining a complete range of motion were recorded in 5 (11 %) of the patients. A flexion contracture of 5° to 7° was also found in 5 patients. Significant patellofemoral symptoms were present in 4 patients (9%). A 5% to 11% shortening of the patella tendon was observed in 14 (32%) of the knees, but did not correlate with patellar problems. Moderate radio graphic changes were noted in eight patients (18%) at followup and correlated with meniscectomy and pain. Overall satisfactory results were obtained in this initial experience in 29 (66%) of the patients. We believe that the operation gives reliable stability in the majority of the cases, but the results may be improved with more attention to isometry, earlier postoperative mobilization with complete extension, and a faster rehabilitation course.
Technique and ground reaction forces in the back handspring
Authors: Koh Timothy J. , Grabiner Mark D. , Weiker Garron G.
Published: June 2007

The ground reaction forces at the hand that produced compression forces and varus/valgus moments at the elbow joint during the double-arm support phase of the back handspring were studied. The relationship of tech nique, namely elbow joint flexion, to these forces were also studied. Compression forces and forces producing valgus moments have been implicated in overuse inju ries to the elbow joint. Video and force plate analysis of six young female gymnasts showed that 1) the elbow joint flexed during the double-arm support phase, and 2) the reaction forces at the hand produced large compression forces (an average of 2.37 times body weight) and sizable valgus moments at the elbow (an average of 0.03 times body weight times body height). The combination of these forces may contribute to the occurrence of lateral compression injuries of the elbow joint (e.g., osteochondritis dissecans of the capitellum). Correlations of measures of elbow angle and measures of reaction force showed that large elbow flexions may protect the elbow from large valgus moments.
The efficacy of continuous passive motion in the rehabilitation of anterior cruciate ligament reconstructions
Authors: Rosen Mark A. , Jackson Douglas W. , Atwell E. Allan
Published: June 2007

Seventy-five patients undergoing arthroscopically-as sisted anterior cruciate ligament reconstruction by the same surgeon were divided into three random subgroups. All of the anterior cruciate ligament recon structions used the middle third of the ipsilateral patellar tendon autograft. Patients undergoing meniscal repair, extraarticular procedures, or repair of other ligaments were excluded. The 75 patients were divided into subgroups to assess the benefits or disadvantages of early active motion (25 patients), continuous passive motion (25 patients), and a combination of both (25 patients) during the first 30 days after surgery.

All patients were evaluated at specific intervals for 6 months after surgery. Data recorded included drain output, medication usage, tourniquet time, leg involved, hospital stay length, KT-1000 testing (before surgery in the anesthetized patient, after the procedure was com pleted, and 2 and 6 months after surgery), and range of motion. Radiographs and the International Knee Evaluation Form were also used to evaluate the results. No statistically significant differences were found be tween the three groups. Side-to-side anterior-posterior differences, stability, and restoration of full range of motion were similar in each subgroup at each evaluated interval. In this prospective study of motion, started immediately after anterior cruciate ligament reconstruc tion, passive and active methods were shown to have identical results. A supervised active and passive mo tion program during the 1 st month had the same results as either one used individually.
Syndesmosis sprains of the ankle
Authors: Taylor Dean C. , Englehardt David L. , Bassett Frank H.
Published: June 2007

A retrospective study of 50 syndesmosis sprains in 44 football players was performed. Five patients (6 ankles) were lost to followup, allowing review of 44 injuries. Average followup was 47 months. The patients were evaluated for recurrent injury, overall ankle function, and for persistent ankle symptoms, including stiffness, pain, limping, and swelling. Follow-up radiographs of the injured ankle were obtained in 22 patients.

The average return time to full activity was 31 days. Pain with pushing-off was a major factor preventing return to activity.

At final followup, 36% of the patients complained of persistent mild to moderate stiffness of the ankle. Twenty-three percent had mild to moderate pain, usu ally with activity. One patient had a mild limp with activity, and 18% of the ankles had persistent mild to moderate swelling. Ankle function was rated as good to excellent in 86%. All patients with fair results had recurrent ankle sprains. There were no poor results.

Eleven of the 22 patients with follow-up radiographs developed heterotopic ossification within the interos seous membrane, but no patient developed a frank synostosis. The patients with heterotopic ossification required an average of 11 days more recovery time than those without ossification. There was no signifi cant difference between the 2 groups' ultimate ratings of ankle function or ankle symptoms, but the ankles with heterotopic ossification were associated with more recurrent lateral ankle sprains.

We conclude that syndesmosis sprains require a longer recovery period than other types of ankle sprains. Most of these injuries showed good to excel lent ankle function after recovery, unless there was a recurrent ankle sprain. In the absence of frank synos tosis, the results were not affected by the formation of heterotopic ossification.
Long-term functional results of the modified Bristow procedure for recurrent dislocations of the shoulder
Authors: Wredmark Torsten , Törnkvist Hans , Johansson Christer , Brobert Birgitta
Published: June 2007

Subjective shoulder function, range of motion, isoki netic muscular performance, and radiographs were analyzed in 44 patients at an average follow-up time of 6 years after a Bristow-Latarjet procedure for recurrent dislocations of the shoulder. The injured shoulder was compared with the healthy side in each patient.

Ninety-five percent of the patients considered mobil ity, strength, and stability of the operated shoulder as good or excellent. Totally, 32 of 44 patients (72%) had no pain or discomfort at all, while the remaining 12 (28%) complained of moderate exertional pain. Range of motion in extension, flexion, abduction, and internal and external rotation did not differ significantly between the injured and healthy sides. Nor did isokinetic peak torque at 30 and 90 deg/sec differ in extension, flexion, or internal and external rotation. The rate of healing of the implant did not seem to influence the functional outcome of surgery. Two patients suffered from recur rent dislocations.

The Bristow-Latarjet procedure provided a good or excellent long-term functional result in patients with recurrent shoulder dislocations.
Function of the quadriceps and hamstrings muscles in knees with chronic partial deficiency of the anterior cruciate ligament
Authors: Kannus Pekka , Jarvinen Markku , Johnson Robert , Renström Per , Pope Malcolm , Beynnon Bruce , Nichols Claude , Kaplan Michael
Published: June 2007

We assessed the isokinetic and isometric strength and power profile of the knees of 37 patients who had a previous grade II sprain (partial tear) of the anterior cruciate ligament. Of the 37 knees, 11 had an isolated partial anterior cruciate ligament rupture and 26 had a partial anterior cruciate ligament rupture combined with a partial medial collateral ligament rupture. The Cybex II isokinetic dynamometer was used in the measure ments.

Eight years after the injury, the mean strength deficit of the injured knees was minimal when compared with the uninjured side. In the hamstrings of both groups, the relative strength deficit increased significantly with a higher speed of isokinetic movement (P < 0.05). Compared with the strength parameters (peak torques), the other functional parameters (total work, average power, and peak angular impulse) of the in jured knees showed some, but not significantly greater, deficits (hamstrings, 7% to 10%; quadriceps, 4% to 10%).

We found that the general thigh muscle function in knees with old grade II sprains of the anterior cruciate ligament appears adequate except in flexion where the strength deficits are significantly greater in higher speeds of isokinetic movement. Therefore, rehabilita tion using high-speed flexion (and extension) exercises is recommended.
Cuboid subluxation in ballet dancers
Authors: Marshall Peter , Hamilton William G.
Published: June 2007

Cuboid subluxation is a common but poorly recognized condition. Its symptoms include lateral midfoot pain and an inability to "work through the foot." In addition, pressing on the plantar surface of the cuboid in a dorsal direction produces pain. The normal dorsal/plantar joint play is reduced or absent when compared to the unin jured side, and subtle forefoot valgus is present. Fre quently, there is a shallow depression on the dorsal surface of the foot and palpable fullness on the plantar aspect of the cuboid. Documentation by radiograph, CT scan, or magnetic resonance imaging is difficult because of the normal variations found in the relation ship between the cuboid and its surrounding structures. The diagnosis is primarily subjective, and must be made on the basis of the patient's history and physical find ings. Treatment requires recognition of the condition, manual reduction by a therapist or physician familiar with the condition, and followup to be certain that the cuboid remains in place. Therapists and orthopaedists involved in the care of dancers should be alert to the possibility of cuboid subluxation and be able to recog nize it when it occurs.
Altered movement and muscular-activation patterns during the one-legged jump in patients with an old anterior cruciate ligament rupture
Authors: Gauffin Håkan , Tropp Hans
Published: June 2007

We studied nine patients with an isolated, unrepaired rupture of the anterior cruciate ligament to evaluate whether well-rehabilitated patients with an old rupture of the anterior cruciate ligament had adapted their patterns of motor control in situations that provoke knee instability and if the possible adaptation results in a measurable decrease of the deteriorating sagittal shear load. The study was performed by means of a movement analysis system with synchronized force plate and electromyographic recordings. A different movement and muscular-activation pattern was found for the injured leg compared to the noninjured when performing a one-legged jump for distance. An internal knee model was developed and implemented. In that way, a simultaneously decreased capsuloligamentous sagittal load at the landing moment was shown.
Multidirectional shoulder instability
Authors: Lebar Randi D. , Alexander A. Herbert
Published: June 2007

We reviewed the results of a capsular shift procedure performed on 10 active-duty patients with an average of 28 months followup. improvement in pain, function, and stability occurred postoperatively in nearly all pa tients. Loss of total elevation and external rotation were minimal and an average of three spinal segments of internal rotation were lost. Only one patient required further surgery for recurrent instability and all patients except two reported over-all improvement. Dominant shoulders made greater improvements in pain, stability, and functional capacity than nondominant shoulders. Patients with generalized ligamentous laxity had less pain and more posterior instability than those without laxity. A history of an acute traumatic event was pre dictive of greater improvement in pain and stability. A previous instability repair was indicative of the most postoperative instability and least functional improve ment.
Anterior-posterior and rotational displacement of the tibia elicited by quadriceps contraction
Authors: Hirokawa Shunji , Solomonow Moshe , Yun Lu  , Lou Zong-Ping , D'Ambrosia Robert
Published: June 2007

The anterior-posterior displacement and rotation of the tibia elicited by isolated loading of the quadriceps mus cle was determined as a function of joint angle and muscle load using a computerized radiographic tech nique. Data collected from 12 fresh-frozen cadaveric knees demonstrated that quadriceps contraction can result in significant (<7 mm) anterior displacement of the tibia in the range of 0° to 80° of flexion, and a mild (<2 mm) posterior displacement in the range of 80° to 120° of flexion. Peak anterior displacement of 6.3 mm was observed at 30° of flexion under a 12 kg load in the quadriceps, while a constant 1.5 mm posterior displacement was observed throughout flexion angles exceeding 80°. It was further shown that the magnitude of the anterior displacement increased nonlinearly as the quadriceps force increased. Loading of the quadri ceps also resulted in internal rotation of the tibia in the range of 0° to 90° of flexion, and in external rotation of the tibia in the range of 90° to 120°. Peak internal rotation of 7° was observed at 15° of flexion and a peak external rotation of 1 ° was detected at 120° of flexion. Larger quadriceps load resulted in larger rota tion. We concluded that quadriceps contraction during knee extension has direct impact on anterior displace ment and rotation of the tibia and therefore on anterior cruciate ligament stress, increasing it as the muscle's force is increased during knee extension. It is sug gested that partial quadriceps atrophy in knees with anterior cruciate ligament deficiency may be explained as a protective response. This would bring into question the practice of quadriceps exercise after ligament inju ries and repair, as well as current orthotics concepts.
Shoulder torque changes in the swimming athlete
Authors: McMaster William C. , Long Susan C. , Caiozzo Vincent J.
Published: June 2007

Torque production was assessed in the shoulders of competitive men and women swimmers for the motions of abduction, adduction, and external and internal ro tation. Testing was performed on the Cybex II dyna mometer and the results were compared to controls. In addition, the ratios of torque development for adduc tion:abduction and external rotation:internal rotation were evaluated. The results demonstrated a statistically significant increase in torque production in swimmers for most motions tested. Statistically significant ratio shifts were also noted. The ratio of adduction:abduction increased and that for external rotation:internal rotation decreased. We think these shifts in the torque ratios in swimmers' shoulders resulted from sport-specific re petitive activity that emphasizes adduction and internal rotation.
Allograft anterior cruciate ligament reconstruction in a sheep model
Authors: Amendola Annunziato , Fowler Peter
Published: June 2007

The purpose of this study was to assess the effect of synthetic augmentation of a bone-patellar tendon-bone allograft on the basis of biomechanical, morphologic, and histologic evaluation. The anterior cruciate ligament was reconstructed in the left knee of 66 adult sheep. Half the knees received bone-patellar tendon-bone grafts alone, while the other half were augmented. All of the knees, including the contralateral controls, had gross and histologic examination, hydroxyproline assay for collagen content, and biomechanical testing in groups at 0, 4, 16, and 52 weeks postoperatively. Biomechanical testing included anteroposterior trans lation, ultimate tensile strength, energy to failure, stiff ness, and mode of failure. Eight fresh bone-patellar tendon-bone allografts were compared to eight cryo preserved bone-patellar tendon-bone allografts for baseline data on the effects of the cryopreservation.

Cryopreservation did not have any effect on graft characteristics. Gross and histologic examination did not reveal any significant difference between the aug mented and nonaugmented groups at any of the time periods. In addition, hydroxyproline content of the al lograft was not altered by augmentation throughout the study period. Biomechanical laboratory evaluation dem onstrated the augmented group had significantly re duced anteroposterior translation (P < 0.05) at 52 weeks compared to the nonaugmented group. The ultimate tensile strength was significantly higher (P < 0.05) in the augmented group at 4 weeks, but at 52 weeks both groups had attained only 50% of the normal anterior cruciate ligament strength. Stiffness and en ergy to failure were similar in both groups at all time periods.

From the results of this study, synthetic augmentation appears to improve initial strength and prevent late allograft laxity while allowing normal remodeling proc esses to occur in the bone-patellar tendon-bone allo graft anterior cruciate ligament reconstruction.
The effect of in situ freezing on rabbit patellar tendon
Authors: Graf Ben K. , Fujisaki Keith , Vanderby Ray , Vailas Arthur C.
Published: June 2007

Cell necrosis has been well documented as one of the many changes that occur in autogenous tendon when it is used to reconstruct the anterior cruciate ligament. The purpose of this experiment was to isolate cell necrosis as a variable and study its effect on the patellar tendon. To accomplish this, both knees of 25 New Zealand White rabbits were operated on. In one knee, a 5-mm wide band of patellar tendon was subjected to two rapid freeze-thaw cycles, while the other knee underwent sham surgery. Histologic evaluation showed a zone of necrosis at 2 and 4 weeks with cellular repopulation complete at 8 weeks. Patellar tendon cross-sectional area was 0.118 cm2 at 8 weeks for the frozen specimens compared to 0.102 cm2 for the sham- operated controls. This difference was significant at the P = 0.025 level. Mechanical testing at 4 and 8 weeks revealed no significant changes in tendon length, max imum load, or stiffness. The collagen content was also unchanged at both 4 and 8 weeks.
Spontaneous fractures of the humerus during pitching
Authors: Branch Thomas , Partin Clyde , Chamberland Patricia , Emeterio Elizabeth , Sabetelle Michael
Published: June 2007

We report the recent occurrence of spontaneous hu meral shaft fractures in 12 pitchers. The subjects were interviewed over the telephone using a standard ques tionnaire. Radiographs and medical records were solic ited from their physicians. Their average age was 36 years and they had pitched an average of 11.4 years with an average layoff of 14 years (range, 7 to 24). Mean time between games pitched was 21 days (range, 3 to 56). The average number of pitches before the fracture occurred was 38 (range, 10 to 100). Pain was experienced at some point before the fracture in 75% of the pitchers and 75% of the fractures were spiral.

These fractures were most probably spontaneous fractures brought on by accumulated fatigue damage. The period of buildup after a prolonged period of layoff was probably insufficient time for proper bone remod eling to occur in these men. While a large percentage of these men had pain before their injury, suggesting a predisposing stress fracture, there is no doubt that their fractures could still be caused by a sudden torsional load without the presence of a stress fracture.
Os trigonum impingement in dancers
Authors: Marotta Joseph J. , Micheli Lyle J.
Published: June 2007

Sixteen patients underwent surgical excision of an im pinging ossicle through a posterior lateral approach. Twelve of these patients (15 ankles) were available for followup and were retrospectively surveyed at an av erage of 28 months after surgery. There were 9 women and 3 men. Nine were professional ballet dancers and 3 were students of advanced ballet schools. Preoper ative symptoms included pain localized to the posterior ankle, limitation of motion, weakness, swelling, or neu rologic changes associated with dance activities. All patients were severely hampered in their dance partic ipation and had failed nonsurgical therapies.

Postoperatively, all patients followed an aggressive rehabilitation protocol. All had improvement in their impingement symptoms; eight (67%) still had occa sional discomfort. All professional dancers returned to unrestricted dance activity. The mean time to full activity was 3 months. One patient had a superficial wound infection requiring antibiotic treatment and another suf fered a transient tibial nerve neurapraxia. Both of these complications resolved without sequelae.

We conclude that posterior ankle impingement in ballet dancers, caused by an os trigonum and resistant to nonsurgical therapies, is effectively treated with sim ple excision of the offending structure.
Fluoroscopic evaluation for subtle shoulder instability
Authors: Papilion John A. , Shall Larry M.
Published: June 2007

Fifty patients with unilateral shoulder symptoms and a variety of diagnoses were evaluated with stress testing of both shoulders under general anesthesia using fluo roscopic documentation just before surgery. An axillary lateral view of the glenohumeral joint was taken in neutral rotation and 90° of abduction; this was termed "neutral position." Anterior and posterior translational stresses were then applied and spot radiographs taken.

Measurements were made and the translation was expressed as a percentage of displacement of the humeral head with respect to the glenoid. The asymp tomatic side was used as a control. We determined that up to 14% anterior translation and up to 37% posterior translation is normal.

Using these guidelines, attempts were made to con firm or predict the presence of stability or instability. Thirty-one patients were correctly identified as stable; 14 were correctly identified as unstable. Three patients with anterior shoulder pain were classified as unstable and found to have Bankart lesions at surgery. Overall, specificity was 100% and sensitivity was 93%. Using discriminant function analysis, a difference score of 10% between the symptomatic and control shoulder was generated. This was useful in eliminating interob server variations in the examination for predicting sta bility or instability.

We recommend this examination as a valuable ad junct to confirm the presence and direction of shoulder instability and predict subtle instability patterns in pa tients with recalcitrant undiagnosed shoulder pain.
Ultrasound examination of soft tissue injury of the lower limb in athletes
Authors: Aspelin Peter , Ekberg Olle , Thorsson Ola , Wilhelmsson Mats , Westlin Nils
Published: June 2007

We performed ultrasonography on 32 athletes com plaining of intense pain in a swollen and tender thigh or calf after a contusion or stretching trauma. The ultra sonogram was used to visualize the presence and size of a suspected hematoma. The findings included the following: 7 patients with a circumscribed, anechoic lesion compatible with a liquefied hematoma; 10 pa tients with a circumscribed lesion of mixed echogenicity compatible with areas of liquefied hematoma, coagu lated blood, and edema; and 15 patients with a diffuse change in echogenicity of the whole muscle. The cir cumscribed liquefied, and mixed hematoma were more common after contusion trauma, while the diffuse type was more common after injury caused by stretching.

Ultrasonography is useful in localizing the hematoma and in characterizing the different types. Differentiation is important in diagnosis and choice of treatment.
A biomechanical analysis of solvent-dehydrated and freeze-dried human fascia lata allografts
Authors: Hinton Richard , Jinnah Riyaz H. , Johnson Carl , Warden Karen , Clarke Hugh J.
Published: June 2007

This study compares the basic mechanical properties of two groups of commercially available fascia lata allografts processed by different means (solvent-dehy drated and sterilized via gamma radiation, and freeze- dried without secondary sterilization). The results reveal significantly ( P < 0.05) higher stiffness, higher maxi mum load to failure, and higher maximum load per unit width of graft with the solvent-dried as opposed to the freeze-dried fascia lata. Subsections of individual sol vent-dried specimens were also more uniform in their mechanical properties than those of the freeze-dried allografts.

Clinical relevance: Fascia lata is used as a graft material in a variety of orthopaedic procedures. Allo graft fascia lata offers an increased cross-sectional area of material and eliminates the morbidity associated with the harvesting of autologous tissues. However, the structural uniformity of such large grafts has been questioned. Processing techniques used in the sterili zation and storage of such grafts is varied and repre sents a potential source of variation in the mechanical properties of allograft specimens. The results of this study suggest that a commercially available solvent- dehydrated form of fascia lata provides a more suitable grafting material than freeze-dried specimens obtained from tissue banks.
Tenotomy of the adductor longus tendon in the treatment of chronic groin pain in athletes
Authors: Akermark Christian , Johansson Christer
Published: June 2007

Eighteen tenotomies of the adductor longus tendon were performed in 16 consecutive male athletes (aged 20 to 42) as treatment for chronic groin pain. The criteria for surgery was a history of long-standing (range, 2.5 to 48 months) and distinct pain at the origin of the adductor longus muscle, refractory to conservative treatment.

At followup 35 months (range, 4 to 84) after surgery, all patients were improved or free of symptoms. All but 1 of the athletes returned to the same sport within a mean of 6.6 weeks, and 12 of 16 returned to competi tive sports within a mean of 14 weeks after surgery. A majority of the patients (10 of 16) returned to full athletic activity, whereas 5 of 16 performed at a reduced level. One patient discontinued his sports activity due to other causes.

In conclusion, when conservative treatment fails, te notomy of the adductor longus tendon gives good long- term functional results in the treatment of chronic groin pain that is localized at the origin of the adductor longus muscle. A decreased muscle strength was observed in this study and did not seem to influence participation in sports.
A multivariate risk analysis of selected playing surfaces in the National Football League: 1980 to 1989
Authors: Powell John W. , Schootman Mario
Published: June 2007

This study focuses on the injury rates for natural grass and AstroTurf surfaces and the risk factors of game position and type of play. We examined the game- related knee sprains, medial collateral ligament sprains, and anterior cruciate ligament sprains that occurred in the National Football League during the 1980 to 1989 seasons. The findings are controlled for categories of severity (number of games missed due to injury), posi tion, and situation (rushing or passing) at the time of injury. The analysis of the data incorporates epidemio logic techniques associated with incidence density ra tios.

The data show that there is a statistically significant difference between the higher AstroTurf injury rates for knee sprains. When knee sprains are separated into medial collateral ligament sprains and anterior cruciate ligament sprains, only the anterior cruciate ligament sprains show a statistically significant higher injury rate for AstroTurf. When simultaneous control variables are considered, significantly more knee sprains occurred to backs on rushing plays and linemen on passing plays. When controlling the data for severity, only the Cate gory II injuries (three or more games missed) sustained by linemen on passing plays had statistically significant higher injury rates for the AstroTurf. For medial collat eral ligament sprains, only the Category II injuries for linemen on passing plays remain statistically significant. The data for the ACL sprains show statistically signifi cant differences between the injury rate on natural grass and the injury rate on AstroTurf under conditions of special teams play.
Arthroscopic labral debridement
Authors: Altchek David W. , Warren Russell F. , Wickiewicz Thomas L. , Ortiz Gerald
Published: June 2007

This is a retrospective review of 40 patients who under went arthroscopic labral debridement of the shoulder. All patients were active participants in sports involving use of the shoulder. All patients presented with shoul der pain. Only 40% were found to have distinct gleno humeral instability on examination. At surgery, all pa tients had labral injury. Ten patients had anterosuperior labral tears, 20 had anteroinferior labral tears or de tachments, and 10 had posteroinferior labral tears or detachments.

Outcome was assessed at a minimum of 2 years (average, 43 months) postoperatively. Overall, only 7% of the patients had significant symptomatic relief at followup. However, 72% noted relief of symptoms dur ing the 1 st year after surgery, but there was deterio ration over time.

Conclusion: Arthroscopic labral debridement is not an effective long-term solution for symptomatic relief in the overhead athlete.
Microscopic histopathology of chronic refractory lateral epicondylitis
Authors: Regan William , Wold Lester E. , Coonrad Ralph , Morrey Bernard F.
Published: June 2007

The histopathologic features from 11 patients who were treated surgically for lateral epicondylitis were graded and compared to similar tissue from 12 cadaveric spec imens. All studies were done by a single pathologist who had no knowledge of the origin of the specimen. The surgical specimens were interpreted as abnormal in all 11 specimens, and all 12 of the control specimens were reported as being without histologic abnormality. Vascular proliferation was present in 10 of 11 and focal hyaline degeneration was recorded in all 11 of the surgical specimens. Neither feature was present in any of the control material (P < 0.001). These data suggest that chronic refractory lateral epicondylitis requiring sur gery is a degenerative rather than inflammatory proc ess. This may account for the lack of response to rest and antiinflammatory medication.
A comparison of anterior compartment pressures in competitive runners and cyclists
Authors: Beckham Susan G. , Grana William A. , Buckley Peter , Breazile James E. , Claypool P.L.
Published: June 2007

Anterior compartment pressure was measured in 10 competitive runners and in 10 competitive cyclists who were asymptomatic for compartment syndrome. Pres sures were measured at rest, after exercise at 80% VO2max, after maximal exercise, and 15 minutes after both exercise bouts. No difference in compartment pressure was found after exercise at 80% VO2max in runners and cyclists. Total creatine phosphokinase en zyme levels measured before and after exercise at 80% VO2max showed a 1 0-fold increase in runners as com pared to cyclists. Anterior compartment pressure meas ured after maximal exercise was significantly greater in runners as compared to cyclists. Compartment pres sure showed no increase from resting values during cycling at 80% VO2max or maximal exercise. These findings suggest that patients with chronic anterior compartment syndrome may be able to cycle without elevation of compartment pressure and concomitant pain as an alternative exercise to maintain a continued degree of fitness and training. Compartment pressures should be measured during cycling in patients with chronic compartment syndrome to determine its effi cacy as a method for maintenance of cardiorespiratory fitness.
A standard measure for exercise prescription for aqua running
Authors: Wilder Robert P. , Brennan David , Schotte David E.
Published: June 2007

Aqua running has been promoted as a method for cardiovascular conditioning for the injured athlete as well as for others who desire a low impact aerobic workout. Recent studies have suggested the need for an environment-specific measure of exercise intensity. Twenty healthy subjects, 10 men and 10 women, underwent a graded exercise test of aqua running to investigate the relationship between cadence and heart rate. This was done to determine the utility of cadence as a measure for exercise prescription. The graded exercise test followed a standard protocol for exercise testing in aqua running. Results demonstrated a high correlation between cadence and heart rate, both as a group as well as individually. We conclude that cadence may be used as a measure for exercise prescription for aqua running.
How iliotibial tract injuries of the knee combine with acute anterior cruciate ligament tears to influence abnormal anterior tibial displacement
Authors: Terry Glenn C. , Norwood Lyle A. , Hughston Jack C. , Caldwell Kenneth M.
Published: June 2007

A knowledge of the patterns of injury to the compo nents of the iliotibial tract allows a clearer interpretation of motion limits testing in patients with abnormal ante rior tibial translation of the knee (anterior cruciate liga ment-deficient knees).

Eighty-two consecutive patients with acute knee in juries were classified as anteromedial-anterolateral ro tatory instability (anterior cruciate ligament-deficient) based on the abnormal motion demonstrated by clinical examination tests for instability. At surgery, injuries to the intraarticular and extraarticular anatomic structures were identified and correlated to the abnormal grades of motion demonstrated by the knee motion limits ex amination.

Tears of the anterior cruciate ligament occurred in 80 (98%) of the knees. However, the grade of abnormal motion demonstrated by the Lachman and pivot shift tests was quite variable. This variation did not correlate statistically with anterior cruciate ligament tears.

Injuries to the anatomic components of the iliotibial tract were confirmed in 76 (93%) of the knees. These injuries correlated highly with variations in grades of abnormal motion detected by the following tests: lateral joint line opening at 30° ( r2 = 0.05); Lachman test ( r2 = 0.08); pivot shift ( r2 = 0.16); and anterior translation at 90° of flexion ( r2 = 0.34). Thus, injuries to the components of the iliotibial tract are thought to contrib ute to the variation in grades of abnormal motion ob served in this complex subgroup of anterior tibial trans lation instabilities.
Radiographic imaging of muscle strain injury
Authors: Speer Kevin P. , Lohnes John , Garrett William E.
Published: June 2007

We reviewed our experience with computed tomogra phy and magnetic resonance imaging of acute muscle strain injury. We imaged 50 athletes (average age, 28 years; range, 17 to 42) who had an acute muscle strain involving either the adductor, hamstring, quadriceps, or triceps surae muscles. Computed tomography (axial imaging) was used from 1982 to 1987 for 27 athletes. Spin-echo magnetic resonance imaging (axial, coronal, sagittal imaging) was used from 1987 to 1991 for 23 athletes.

Computed tomography and magnetic resonance im aging localize the strain injury to a single muscle within a group of synergists; the adductor longus, rectus femoris, and medial head of gastrocnemius muscles are most prone to strain injury. A disruption occurs predictably at the myotendinous junction; fluid collects at the disruption site and dissects along the epimysium and subcutis. Muscle tissue remote from the myoten dinous junction clearly demonstrates extensive injury with abundant magnetic resonance imaging signal changes consistent with edema and inflammation. Fol low-up computed tomographic and magnetic reso nance imaging studies can clearly demonstrate atrophy, fibrosis, and calcium deposition.
Does amateur boxing lead to chronic brain damage?
Authors: Haglund Yvonne , Eriksson Ejnar
Published: June 2007

Fifty former amateur boxers were examined and com pared with two control groups of soccer players and track and field athletes. All subjects were interviewed regarding their sports career, medical history, and so cial variables. They underwent a physical and a neuro logic examination. Personality traits were investigated and related to the platelet monoamine oxidase activity. Cerebral morphologic changes were evaluated using computed tomography and magnetic resonance imag ing. Further, clinical neurophysiologic tests were made as well as neuropsychologic tests.

No significant differences were found between the groups in any of the physical or neurologic examinations or in platelet monoamine oxidase activity. Socially, the boxers had a lower degree of education and had cho sen less intellectual professions, but they were less impulsive and more socialized. The computed tomog raphy images and magnetic resonance imaging studies showed no significant differences between the groups. There was a significantly higher incidence of slight or moderate electroencephalography deviations among the boxers. Neuropsychologically, the boxers had an inferior finger-tapping performance. Thus, no signs of serious chronic brain damage were found among any of the groups studied. However, the electroencepha lography and finger-tapping differences between the groups might indicate slight brain dysfunction in some of the amateur boxers.
Repair of distal biceps tendon ruptures in athletes
Authors: D'Alessandro Donald F. , Shields Clarence L. , Tibone James E. , Chandler Robert W.
Published: June 2007

Ten athletes with distal biceps tendon ruptures that had been anatomically repaired with a double-incision technique were reviewed to determine their functional recovery. All of the patients were men, with an average age of 40 years (range, 25 to 49). Eight of the 10 patients were weight lifters or body builders, and 7 had participated on a competitive level at some point in their athletic careers. Six injured their dominant extremity, and 4 their nondominant extremity. Isokinetic muscle testing of supination and flexion was performed in 8 patients and the results were compared to a control group. Followup averaged 50 months (range, 12 to 105).

Patients uniformly graded their subjective results as excellent, with a group mean rating of 9.75 on a 10- point scale. All athletes returned to full, unlimited activ ity. The contour of the biceps muscle was restored in all cases. Isokinetic muscle testing demonstrated that in those patients with a repaired dominant extremity, supination strength and endurance was normal; in flex ion, they had normal strength, but averaged 20% less endurance. Testing of the group that had the nondom inant extremity repaired revealed a supination strength deficit of 25%, but normal endurance. Flexion strength and endurance were essentially normal in this group.

Anatomic repair of a distal biceps tendon rupture gives consistently excellent subjective and good objec tive results in athletes, particularly for those sports with high strength demands such as weight lifting and body building. Rehabilitation of the operated arm, especially the repaired nondominant extremity, should be empha sized.
Articular cartilage lesions in ankles with lateral ligament injury
Authors: Taga Ichiro , Shino Konsei , Inoue Masahiro , Nakata Ken , Maeda Akira
Published: June 2007

To investigate intraarticular lesions producing persist ent postoperative pain, we arthroscopically examined 31 ankles in 31 patients (15 women and 16 men) with lateral ligament injury. The patients ranged in age from 15 to 33 years, with a mean of 20 years. Nine patients were freshly injured, and 22 patients had chronic inju ries. All of the patients underwent arthroscopic exami nation immediately before the ligament operation. Chondral lesions were found in 89% of the freshly injured ankles and 95% of the ankles with chronic injuries. Most of these lesions were in the medial half of the ankle joint, especially in the anteromedial edge of the tibial plafond. After followup for 1 year postop eratively, persistent pain was noted in 4 patients who had chondral lesions of greater than one-half the thick ness of the articular cartilage. Pain and tenderness were localized at the anteromedial joint line, corre sponding to the location of the chondral lesions. Chon dral lesions of greater than one-half the thickness of the articular cartilage were found in 8 ankles in the chronic injury group, but there were none in the fresh injury group.

Thus, in lateral ligament injuries of the ankle, the longer the time elapsed from the initial injury, the more severe the associated chondral lesions became. These chondral lesions appear to cause persistent pain.
Incidence and nature of sports injuries in Ireland
Authors: Watson Anthony W.S.
Published: June 2007

The objectives of this study were to investigate the incidence of sports injuries in Ireland and to analyze various ways of quantifying the seriousness of these injuries. A 12-month, prospective study was carried out on 324 Irish athletes involved at a high level of sports participation in one of the following categories: endur ance, contact, noncontact, or explosive sports. Results were expressed in four ways: 1) number of injuries per year; 2) days injured per year; 3) number of injuries per 10,000 hours of participation; and 4) duration of injury per 1000 hours of participation.

The average athlete sustained 1.17 acute and 0.93 overuse injuries per year and suffered the effects of sports injury for 52 days. More time was lost through overuse injuries than acute injuries. The incidence of acute injuries per 10,000 hours of participation was lowest in the noncontact sports and highest in the contact sports, but there was no difference in the incidence of overuse injuries between any of the four categories of sport. The injury rate per 10,000 hours of participation was lowest in noncontact and explosive sports and highest in contact sports. However, when expressed in terms of days lost per 1000 hours of participation, endurance sports had the lowest inci dence of time loss and explosive sports the highest.
Experimental muscle strain injury
Authors: Taylor Dean C. , Dalton James D. , Seaber Anthony V. , Garrett William E.
Published: June 2007

The structural and functional strength of a muscle immediately after an experimentally created strain injury was examined to provide clinically relevant information for the early treatment of muscle strain injuries. The extensor digitorum longus muscles of 12 adult male rabbits were studied. Contractile force and shortening, and peak load were determined for control muscles. A nondisruptive strain injury was created by stretching the experimental muscles just short of complete rup ture. Contractile force generation and shortening, and peak load were determined after the experimental strain injury. Peak load was 63% and elongation to rupture was 79% for the experimental muscles relative to the controls. Statistically significant lower values for con tractile force generation and shortening were also seen in the experimental muscles. Histologic and gross ex aminations revealed that incomplete disruptions oc curred near the distal muscle-tendon junction. These experimental data suggest clinical implications, such as 1) a muscle-tendon unit is significantly more susceptible to injury following a strain injury than normal muscle, 2) early return to the uncontrolled environment of athletic competition may place the injured muscle at risk for further injury, and 3) therapeutic regimens designed to achieve an early return to competition may further increase the risk for additional injury by eliminating protective pain mechanisms. Although the decrements in peak load and elongation to failure are less than normal muscle, the values seem high enough to allow mobilization of the injured extremity and functional re habilitation.
An in vitro analysis of patellofemoral contact areas and pressures following procurement of the central one-third patellar tendon
Authors: D'Agata Samuel D. , Pearsall Albert W. , Reider Bruce , Draganich Louis F.
Published: June 2007

Patients have complained of pain after the use of the central one-third patellar tendon for reconstruction of the anterior cruciate ligament-deficient knee. This study investigated the effect on patellofemoral contact areas and pressures of harvesting the central 10 mm of the patellar tendon in five cadaveric knees. Isometric quad riceps forces were applied to produce approximately 30% of reported maximum voluntary extension mo ments at the knee. Using Fuji pressure-sensitive film, measurements were recorded for three states: the normal knee, after the graft removal, and after the tendon was closed. Contact areas and pressures were measured at 20°, 30°, 60°, and 80° of knee flexion in each specimen. Tests of the reproducibility of our meth ods were performed.

Average patellofemoral contact areas for three states ranged from 1.6 cm2 at 20° of knee flexion to 3.0 cm2 at 60°. The average patellofemoral contact pressures ranged from 1.9 MPa at 20° of knee flexion to 3.0 MPa at 30°. At each flexion angle there were no significant differences in average patellar contact area or pressure for the three states ( P < 0.05). These results suggest that neither harvesting the central 10 mm of the patellar tendon, nor closing the gap, significantly alters patello femoral contact area or pressure.
The influence of an ankle orthosis on the talar and calcaneal motions in chronic lateral instability of the ankle
Authors: Löfvenberg Richard , Karrholm Johan
Published: June 2007

The mechanical support provided by a semirigid ankle orthosis was tested in 14 ankles with symptoms of chronic lateral instability by use of stereophotogram metric analysis. Talar and calcaneal rotations were measured with and without the Strong ankle orthosis during manual adduction test and adduction test with a predetermined torque (5 N-m). Significant reduction of talar and calcaneal plantar flexion, internal rotation, and varus angulation was noted when the orthosis was applied. The results of this study suggest that the semirigid orthosis may provide enough external support to prevent ankle sprains and to protect ligament recon structions.