The American Journal of Sports Medicine

We describe spear tackler's spine, a clinical entity that constitutes an absolute contraindication to participation in tackle football and other collision activities that ex pose the cervical spine to axial energy inputs. A subset of football players were identified who demonstrated: 1) developmental narrowing (stenosis) of the cervical canal; 2) persistent straightening or reversal of the normal cervical lordotic curve on erect lateral roentgen ograms obtained in the neutral position; 3) concomitant preexisting posttraumatic roentgenographic abnormal ities of the cervical spine; and 4) documentation of having employed spear tackling techniques. From data obtained by the National Football Head and Neck Injury Registry and the senior author's practice, 15 cases of spear tackler's spine were identified during 1987 to 1990.

All 15 cases were evaluated because of complaints referable to the cervical spine or brachial plexus result ing from football injuries. Of these, 11 had complete neurologic recovery without permanent sequelae. Four cases resulted in permanent neurologic deficits: quad riplegia, 2; incomplete hemiplegia, 1; and residual long track signs, 1. Permanent neurologic injury occurred as the result of axial loading of a persistently straightened cervical spine from use of head-impact playing tech niques. We suggest that individuals who possess the aforementioned characteristics of spear tackler's spine be precluded from participation in collision activities that expose the cervical spine to axial energy inputs.

This study was designed to determine the cause of upper trunk brachial plexopathy, which is referred to as a "stinger" or a "burner." This injury often has been thought to occur secondary to traction when an athlete sustains a lateral flexion injury of the neck. At the United States Military Academy, a 4-phase study was begun with 261 tackle football players (236 intramural- and 25 varsity-level players) to investigate this injury. Electro myography and nerve root stimulation studies were used to delineate the lesion, which was found in a total of 32 players who continued throughout the study. This study demonstrated that a much more common mech anism of injury resulting in the stinger syndrome is probably compression of the fixed brachial plexus be tween the shoulder pad and the superior medial scapula when the pad is pushed into the area of Erb's point, where the brachial plexus is most superficial. An or thosis was designed to protect the brachial plexus from the compressive force of the shoulder pad. In prelimi nary trials, this orthosis had been very effective in decreasing the number of episodes in which stinger injuries occurred.

The arthroscopic transglenoid suture technique was performed on 38 shoulders for antenor capsulolabral repair or reconstruction. The primary complaint was instability in 34 shoulders (89%) and pain in 4 shoulders (11 %). In the instability subgroup, 3 (9%) experienced instability in their sleep, 17 (50%) with activities of daily living, and 14 (41 %) with athletic activities.

Arthroscopic examination revealed labral detachment in 35 shoulders (92%) with additional capsular abnor malities noted in 17 (45%). The remaining 3 shoulders (8%) demonstrated capsular laxity and thinning without labral detachment.

Twenty-nine shoulders had complete relief of insta bility. There were no redislocations. Four shoulders (10%) had recurrence of instability. Twenty shoulders (53%) obtained full range of motion, 15 (39%) had minor (<10°) loss of external rotation, 2 (5%) experienced greater (>10°) loss of external rotation, and 1 improved over a restricted preoperative range of motion.

Fifteen of the 20 competitive athletes and 11 of the 15 recreational athletes returned to the same level and same type of athletic activity. Five patients did not resume their preinjury athletics because of unrelated life-style changes; they reported no shoulder problems. Four patients significantly reduced their athletic partic ipation because of postoperative instability or residual pain.

In conclusion, relief of apprehension, reestablishment of shoulder stability and return to athletic activity, in cluding contact and throwing activities, can be achieved safely and effectively in appropriately selected patients.

A total of 86 modified Bristow procedures were per formed for anterior shoulder instability between 1975 and 1987. Followup on 79 shoulders (92%) was ob tained at an average postoperative time of 8.6 years. The redislocation rate was 4%. Average motion loss was 5° of internal rotation and 9° of external rotation. Fifteen percent of the patients examined expressed mild apprehension with the shoulder abducted and externally rotated. Radiographic bone union of the coracoid transplant was noted in 82% of patients. Additional surgical procedures were required in 14% of patients. Seventy-three percent of the reoperations were for screw removal because of persistent shoulder pain. The average subjective shoulder function was rated at 86% of preinjury level. All throwing athletes were able to return to throwing, although 54% of the patients with dominant shoulder involvement noted a decrease in throwing velocity. Ninety-seven percent of the patients rated their results as good or excellent.

We reviewed the meniscal status of 176 consecutive patients undergoing anterior cruciate ligament recon struction acutely (less than 6 weeks from injury), sub- chronically (6 weeks to 12 months from injury), and chronically (more than 12 months from injury). The commonest tear was the single longitudinal vertical split of the medial meniscus. There was an increasing inci dence of meniscal tears as the injury became more chronic, with a significant (P < 0.001) increase in medial meniscal tears; the incidence of lateral meniscal tears remained relatively constant.

Seventy-five (43%) of the patients had one or both menisci repaired. Acutely, repair was performed more frequently on the medial meniscus than the lateral (80% versus 24%, respectively). All repaired menisci had single longitudinal tears unstable to probing. The inci dence of repair dropped to 46% in the medial meniscus and 14% in the lateral meniscus in the chronic stage.

Nineteen (25%) of these 75 patients (26 menisci) underwent a check arthroscopy at a minimum of 6 months from repair. All 21 medial menisci and all 5 lateral meniscal tears had healed; however, 1 lateral meniscus had torn along the line of the sutures.

At an average followup of 40 months, 92% of the repaired menisci were still in situ and 8% that had required resection were related to the recurrence of anterior cruciate ligament instability.

This study highlights the increasing incidence of men iscal injury in chronic anterior cruciate ligament insuffi ciency with the meniscal tears becoming more complex and therefore less amenable to suture. We recommend that patients with anterior cruciate ligament instability be investigated for repairable meniscal tears and that ligament stabilization of the knee and meniscal sutures be considered early.

The purpose of this study was to determine in a prospective, randomized, blinded design whether ar throscopically assisted anterior cruciate ligament reconstruction offered any significant immediate or short-term advantages over traditional open recon struction through a limited arthrotomy. Patients with a diagnosis of deficiency of the anterior cruciate ligament were randomly assigned to one of two treatment groups: the open group (limited open reconstruction) or the arthroscopic group (fully arthroscopic reconstruc tion). Postoperatively, both groups were treated iden tically. Intra- and postoperative observations included length of surgery, duration of hospitalization, and amount of pain medication. Follow-up evaluations were performed at 1, 6, 12, 16, 20, and 24 weeks to record crepitus, swelling, range of motion, ligament laxity, and thigh atrophy. Lysholm scores were obtained at the 16 and 24 week followups.

At 24 weeks, 86% of the open group and 89% of the arthroscopic group had good-to-excellent results. Intra operative, postoperative, and follow-up findings indi cated no statistically significant differences or relation ships between the two groups in any of the variables measured, except that operative time was 13 minutes longer in the arthroscopic group (P < 0.001). The results do not substantiate a clinical advantage for either technique.

We reviewed a consecutive series of young sympto matic patients with chronic anterior cruciate ligament- deficient knees to determine if an autogenous patellar tendon graft reconstruction decreased their symptoms and increased the stability of the knee. All patients had radiographic evidence of posttraumatic arthritis. Thirty- three patients met our criteria for inclusion in the study. Time from injury to reconstruction of the anterior cru ciate ligament averaged 105 months. All patients under went an accelerated rehabilitation program designed to help them regain full range of motion as soon as pos sible. Preoperative and postoperative range of motion, strength, stability, and subjective evaluations were compared. Followup averaged 44.8 months. Follow-up range of motion was not significantly different from preoperative measurements (P = 0.51). Postoperative stability, as measured by KT-1000 arthrometer maxi mum manual test, averaged 2.7 mm versus 8.4 mm preoperatively (P < 0.001). Isokinetic testing revealed no difference in the quadriceps strength after recon struction (P = 0.99). Patients' subjective scores on a modified Noyes questionnaire improved for pain, sta bility, and activity level, with a total improvement from 55 to 81 points. Although the procedure and rehabili tation were successful in providing stability and de creasing pain, patients were still encouraged to limit high-impact athletic and occupational activity.

Long-term stability of the knee after anterior cruciate ligament reconstruction is imperative. Testing protocols that use isokinetic systems are commonly performed despite controversies as to their safety. The purpose of this study was to test whether one episode of isokinetic testing would cause an increase in anterior tibial translation. Twenty-four subjects who had anterior cruciate ligament recontructions 153 to 300 days earlier volunteered for the study. Initially, subjects walked on a treadmill at 5 km/hr for 10 minutes to test the effect of exercise on displacement measurements. One week later, subjects performed a maximal knee flexion-exten sion test on the Cybex dynamometer at 60, 150, and 240 deg/sec. Anterior tibial displacement at 133.5 N was obtained from force-displacement curves pro duced by KT-2000 arthrometer testing at nine intervals: before exercise on the treadmill, at four intervals after treadmill exercise, and at four intervals after Cybex testing. Repeated measures analysis of variance did not show a significant exercise effect, interaction be tween type of exercise and time interval, or change after Cybex testing for the reconstructed knee displace ment, the contralateral knee displacement, or side-to- side difference. The average difference before and after Cybex testing was 0.1 mm for the reconstructed knee. In conclusion, a single Cybex test, performed at least 6 months after surgery, did not affect anterior tibial displacement in this study sample.

In this 3-year prospective study, the incidence and nature of injuries incurred by a professional rugby league football club were investigated. During the 1989, 1990, and 1991 season games, 141 injuries occurred throughout the first, second, and under-21 age teams, which resulted in players missing subsequent games.

The incidence of injury was 44.9 per 1000 player- position game hours, which is high when compared with other sports. Of these injuries, 37.6% were clas sified as minor, 34.8% as moderate, and 27.6% as major. The classification was based on the number of subsequent games missed: minor injuries caused a player to miss one game; moderate, two to four games; and major, five or more games.

Ligament and joint injuries comprised 53.9% of all injuries, and the knee was the most common area injured (24.1 %). The commonest specific injuries were to the medial collateral ligament of the knee and to the groin musculotendinous unit (10.6% each).

Information on the rate and spectrum of snowboarding injuries is limited. This 4-year prospective study at 3 major Australian ski resorts assesses incidence and patterns of snowboarding injuries, particularly in rela tion to skill level and footwear. Ski injury data were collected for the same period. In a predominantly male study population (men:women, 3:1), 276 snowboarding injuries were reported; 58% occurred in novices. Fifty- seven percent of injuries were in the lower limbs, 30% in the upper limbs. The most common injuries were sprains (53%), fractures (24%), and contusions (12%). Comparing skiers' versus snowboarders' injuries, snowboarders had 2.4 times as many fractures, partic ularly to the upper limbs (21 % versus 35% of upper limb injuries), fewer knee injuries (23% versus 44% of lower limb injuries), but more ankle injuries (23% versus 6% of lower limb injuries). Ankle injuries were more common with soft-shell boots, worn most by interme diate and advanced riders. Knee injuries and distal tibial fractures were more common with hard-shell boots, worn most by novices. Overall, novices had more upper limb fractures and knee injuries; intermediate and ad vanced riders had more ankle injuries. Falls were the principal mode of injury. To prevent injury, beginners should use "hybrid" or soft-shell boots and take les sons.

Physical training-related injuries are common among army recruits and other vigorously active populations, but little is known about their causation. To identify intrinsic risk factors, we prospectively measured 391 army trainees. For 8 weeks of basic training, 124 men and 186 women (79.3%) were studied. They answered questionnaires on past activities and sports participa tion, and were measured for height, weight, and body fat percentage; 71 % of the subjects took an initial army physical training test. Women had a significantly higher incidence of time-loss injuries than men, 44.6% com pared with 29.0%. During training, more time-loss in juries occurred among the 50% of the men who were slower on the mile run, 29.0% versus 0.0%. Slower women were likewise at greater risk than faster ones, 38.2% versus 18.5%. Men with histories of inactivity and with higher body mass index were at greater injury risk than other men, as were the shortest women. We conclude that female gender and low aerobic fitness measured by run times are risk factors for training injuries in army trainees, and that other factors such as prior activity levels and stature may affect men and women differently.

The purpose of this study was to evaluate the effect of a health education intervention on running injuries. The intervention consisted of information on, and the sub sequent performance of, standardized warm-up, cool- down, and stretching exercises. Four hundred twenty- one male recreational runners were matched for age, weekly running distance, and general knowledge of preventing sports injuries. They were randomly split into an intervention and a control group: 167 control and 159 intervention subjects participated throughout the study. During the 16-week study, both groups kept a daily diary on their running distance and time, and reported all injuries. In addition, the intervention group was asked to note compliance with the standardized program. At the end of the study period, knowledge and attitude were again measured. There were 23 injuries in the control group and 26 in the intervention group. Injury incidence for control and intervention sub jects was 4.9 and 5.5 running injuries per 1000 hours, respectively. The intervention was not effective in re ducing the number of running injuries; it proved signifi cantly effective (P < 0.05) in improving specific knowl edge of warm-up and cool-down techniques in the intervention group. This positive change can perhaps be regarded as a first step on the way to a change of behavior, which may eventually lead to a reduction of running injuries.

Nine patients (8 men and 1 woman, ranging in age from 17 to 22 years) who sustained a Jones fracture were treated with percutaneous intramedullary screw fixation as outpatients. All of the patients were varsity athletes. Seven were Division I scholarship athletes. Beginning at 7 to 10 days after surgery, all patients were allowed weightbearing as tolerated with a CAM walker. Station ary bicycling, swimming, and Stairmaster were allowed at 2 to 3 weeks. The average return to running was 5.5 weeks (range, 3 to 10). The average return to full competition was 8.5 weeks (range, 7 to 12). No periop erative or postoperative complications occurred. Aver age followup was 2.5 years. All fractures attained clin ical and radiographic union. We believe that outpatient percutaneous intramedullary screw fixation of the acute Jones fracture is a reasonable alternative for those active patients who would have difficulty with a non- weightbearing cast and crutches or who desire an expeditious return to activities. Time restraints are par ticularly critical for in-season or preseason athletes. With the outpatient screw fixation method, our patient population had predictable healing, and they returned to full sports participation within 12 weeks.

Fourteen patients underwent percutaneous Achilles tendon repairs between 1982 and 1989 for ruptures approximately 2 to 8 cm from the calcaneal insertion. They were evaluated subjectively (questionnaires) and objectively (physical examinations, Cybex II dynamom eter). The minimum follow-up time was 2 years with an average of 3.8 years. Subjectively, all of the patients were satisfied with their overall results. Objectively, no significant difference was demonstrated by Cybex II evaluation at 60 and 120 deg/sec. A significant differ ence was seen at 180 deg/sec, but this represented only a 13% loss of power. No infections, delayed wound healing, reruptures, or evidence of thrombophlebitis were noted. There was one sural nerve injury.

To quantify normal motion, medial and lateral passive patellar motion limits were measured in 67 high school athletes randomly selected from a group of 1340 ath letes undergoing preseason physical examinations. Pa tellar displacement was measured at knee flexion an gles of 0° and 35°, using both a Patella Pusher (a hand held force gauge) and a manual technique, and the results were compared. Demographic data and physical examination of the deceleration mechanism (Q angle, vastus medialis obliquus dysplasia, patella alta and baja, and valgus and varus alignment) were correlated with patellar motion limits.

With the knee in extension, passive displacement of the patella averaged 9.6 mm medially and 5.4 mm laterally. In flexion, medial displacement averaged 9.4 mm and lateral displacement averaged 10.0 mm. No positive correlations were found between demographic data or deceleration mechanism examination parame ters and patellar motion limits, suggesting that motion produced by the displacement force was limited by ligamentous restraints only.

The clinical assessment of the passive limits of pa tellar motion should include examination at knee flexion angles of 0° and 35°. The manually produced displace ment was found to be more reproducible than displace ment by the Patella Pusher (P < 0.05).

The primary purpose of a prophylactic knee brace is to decrease injury potential without compromising joint function; however, the extent that these devices can alter knee muscle function is not clear. This study investigated effects of nonprescription prophylactic knee bracing on lower extremity joint position and muscle activation during running. Six healthy male col lege-aged recreational runners used a motor-driven treadmill under 6 conditions: fast or slow speeds, with and without wearing a prophylactic knee brace, and with and without wearing a weighted vest. Changes in hip, knee, and ankle joint position and electromyo graphic activity from 9 lower extremity muscles were monitored during the running cycle weightbearing phase. Results revealed significant changes (P < 0.05) in joint position and electromyographic activity for com parisons of slow versus fast, braced versus nonbraced, and weighted versus nonweighted conditions. From 83% to 89% of the braced and nonbraced comparisons generated significant differences in knee joint position while significant hip and ankle joint position changes occurred in 50% to 58% of comparisons. From 67% to 83% of braced and nonbraced comparisons for the 9 muscles produced significant differences in electromyo graphic activity. Findings suggest that neuromuscular control is altered when external prophylactic devices are applied.

Harvesting the central third of the patellar tendon for autograft anterior cruciate ligament reconstruction is thought to compromise quadriceps strength and func tional capacity. We compared objective measurements of quadriceps strength and functional capacity in ath letes after patellar tendon autograft or allograft anterior cruciate ligament reconstruction. We looked at 33 ac tive male patients (mean age, 24.3 years) who had anterior cruciate ligament reconstructions 12 to 24 months earlier using patellar tendon autograft (N = 15) or allograft (N = 18) techniques. All patients under went an intensive rehabilitation program. Quadriceps strength and power were assessed by measuring peak torque at 60 and 240 deg/sec, torque acceleration energy at 240 deg/sec, and the quadriceps index using a Cybex II isokinetic testing device. Functional capacity was evaluated based on the results of 3 specially designed functional performance tests and the hop test. Results revealed no significant difference between au tograft and allograft groups with respect to any of these parameters. These findings indicate that harvesting the central third of the patellar tendon for autograft anterior cruciate ligament reconstruction does not diminish quadriceps strength or functional capacity in highly active patients who have intensive rehabilitation. Thus, the recommendation to avoid patellar tendon autograft anterior cruciate ligament reconstruction to preserve quadriceps strength and functional capacity may be unnecessary.

The KT-1000 arthrometer was evaluated in vitro and in vivo to determine accuracy and quantify effects of potential error sources in clinical application. The KT- 1000 arthrometer in vitro accuracy was evaluated by making 30 measurements of 13 known displacements (range, +15 to -15 mm). The effect of applied force on malalignment measurements was evaluated in vitro by making repeated measurements with force applied 5°, 10°, and 15° from the vertical position. The effect of malpositioning the device along the joint line was eval uated in vivo by making repeated measurements 1 cm proximal and 1 cm distal to the joint line. The KT-1000 arthrometer was accurate in vitro (average error, 0.13 mm; SD, 0.12 mm). The range of measurements in creased when the angle of force application was in creased. Positioning the device 1 cm proximal to the joint line produced larger anterior translation measure ments in vivo than those at the joint line (5.8 versus 5.4 mm), while positioning it 1 cm distal produced smaller measurements (4.4 mm). The KT-1000 arthrometer's accuracy indicates great potential for clinical applica tion, but one must ensure that the displacing force is directed properly and the device is positioned accu rately over the joint line.