Proceeding Highlights

First

Meeting of the American Orthopaedic Society for Sports Medicine Robert L. Larsen, M.D., Eugene, Oregon meeting of the American Orthopaedic Society for Sports Medicine was Membership Committee held February 7, 1973 in Las Vegas, NeDonald B. Slocum, M.D., Eugene, vada, under the presidency of Dr. Don H. Oregon-CHAIRMAN O’Donoghue. The papers summarized here Marcus J. Stewart, M.D., Memphis, Tenn. were presented at that meeting. (The full Frank C. McCue, III, M.D., Charlottestext of Dr. O’Donoghue’s Presidential Adville, Virginia dress appeared in Volume 1, Number 3, of Gerald A. O’Connor, M.D., Ann Arbor, the Journal of Sports Medicine. Reprints Mich. available on request.) John D.

Te

first

Leidholt, M.D., Denver, Colorado

OFFICERS OF THE AOSSM Committee

on

Publication

Board of Directors

D. Godfrey, M.D., Buffalo, New York-PRESIDENT Jack C. Hughston, M.D., Columbus, Georgia-PRESIDENT ELECT Joe W. King, M.D., Houston, Texas-VICE PRESIDENT William C. Allen, M.D., Gainesville,

Joseph

Florida-TREASURER Leslie M. Bodnar, M.D., South Bend, Indian a-SE CR ETARY Don H. O’Donoghue, M.D., Oklahoma City, Oklahoma-PAST PRESIDENT

Program

Committee

Martin Blazina, M.D., Inglewood, California-CHAIRMAN Bernard Cahill, M.D., Peoria, Illinois

102

Charles A. Rockwood, Jr., M.D., San Antonio, Texas-CHAIRMAN H. Royer Collins, M.D., Cleveland, Ohio Frank H. Bassett III, M.D., Durham, North Carolina John J. O’Hara, M.D., Redondo Beach, Calif. Americo Savastano, M.D., Providence, R.I. Committee

D.

on

Research and Education

Kay Clawson, M.D., Waslllngtori-CHAIRMAN

Seattle,

Gael R. Frank, M.D., Edmond, Oklahoma Stanley L. James, M.D., Eugene, Oregon John C. Kennedy, M.D., London, Ontario, Canada James A. Nicholas, M.D., New York City



Ligament Injuries of the Metacarpalphalangeal Joint of the Thumb

pollicis attachment to the proximal phalanx was performed in 24 of the 25 cases. Eight patients required volar plate reconstruction. In the acute group, distal reattachment of the ligament to penof the adductor

Ulnar Collateral

m

Athletes FRANK C MCCLE, III, M D, Hand Service Diof Orthopaedic Surgery, Umversity of Virginia Medical Center, Charlottesville

vision

with the pull-out wire was Distal reattachment performed with volar plate repair in 2 cases, distal repair with adductor pollicis advancement in I case and K-wire fixation of the avulsion fracture of the base of the proximal phalanx osteum and bone in

MICHAEL HAKALA, M D , JAMES R ANDREWS, M D AND JOSEPH H GIECK, M.D , Hand Service, University of Virginia Medical Center

Dr.

McCue and his associates have reviewed the anatomy of the metacarpophalangeal joint of the thumb and have discussed the mechanism of injury to this joint as well as the disability which has occurred as a result of it. The diagnostic features of this injury are history of strain in the radial direction with pain and swelling in the web space in the base of the thumb and weakness of the thumb-index pinch. On examination, the patients showed a local tenderness over the ulnar collateral ligament, pain in the joint when testing for radial stability, swelling along the ulnar side of the metacarpal head, weakness of thumbindex pinch and instability in cases of complete tear of the ulnar collateral ligament. The authors reviewed 41 cases of injury to the ulnar collateral ligament of the metacarpophalangeal joint of the thumb in athletes treated surgically on the Hand Service at the University of Virginia Hospital during the period from January, 1961 through June, 1972. Twenty-five of these cases were chronic, having been seen longer than 4 weeks after injury, with 16 cases being acute. Twenty-two of the athletes were injured playng football, with 4 injured dunng participation in baseball, 4 in wrestling and 4 in skiing. Basketball accounted for 3 injuries. Lacrosse, softball and polo and horse jumping resulted in I injury apiece The right hand was injured in 25 patients and the left hand in 16 patients. The age of the atheletes ranged from 15 to 56 years, with the average age at the time of the injury being 21.4 years. Each of the patients requested surgery because of subjective weakness and disability. In the chronic cases, distal advancement or reattachment of the torn ligament combined with the advancement

was

12

performed

cases.

in

I

case.

The surgical result was excellent or good in all of the 16 acute cases Conservative care had failed in all of the chronic cases and in 24 of the 25 chronic cases, the result was either good or excellent after reconstructive procedure was performed. The best results, however, were obtained in the acute cases who had primary ligamentous repair. All athletes who participated in team sports subsequently returned to play at the same position without any noticeable change in their functional ability. The authors review the literature on this subject and in summary, stress the importance of acute repair of this injury in order to avoid weakness of thumb-index pinch.

Performance and

Synthetic JAMES G

Turf

in

Safety Characteristics of Football

GARRICK, M D , Head, Division of

Sports Medicine, Department of Orthopaedics, University of Washington School of Medicine, Seattle, Washington. RALPH K REQUA, Director of Research, Division of Sports Medicine, University of Washington School of Medicine, Seattle.

Te

authors have attempted to study the friction characteristics of synthetic turf and also do an epidemiological study of injury rates on synthetic turf as compared to grass. The force needed to pull a weighted plywood block and later a weighted football shoe across synthetic turf in various directions and in various areas of the field exhibiting different wear patterns was measured with the field dry and then wet. The direction of lean or nap influenced the force necessary to 103

move the block (more force was needed when pulling against the nap). Increasing age and wear of the surface also increased the coefficient of friction. On Astro Turf when the field was new, a player was 3 times as likely to slip and fall when cutting with the direction of the turf when it was wet. With increasing age of the surface, this tendency increased and after 3 years, the player was 9 times as likely to slip when compared to cutting against the grain In 1970 and 1971, 4,270 players from various high school teams in the Seattle, Washington area were studied epidemiologically to determine the rate of injury on artificial surfaces compared to grass. The injury rate was 32% higher on Astro Turf than grass with the incidence of injury on dry Astro Turf nearly double than seen on grass, (wet or dry). In 1971, the injuries occurring on a Tartan Turf field were included and the rate of injuries on this surface was found to be lower than on either Astro Turf or grass. In 1972, injuries occurring at the University of Washington over a 3 year period were analyzed and a rate of 4.05 lost time injuries per game on Astro Turf were found. This compared to 3.57 injuries per game on grass. From this study, the authors conclude that injuries are more common on Astro Turf in their area and that Tartan Turf produced the fewest number of injuries.

The Anteromedial Knee

Approach

to Evaluate

JAMES R

A-,DRLBNS, M D , Hughston Orthopaedic Clinic, PC, 1315 Delauney Avenue, Columbus, Georgia 319011 HUGHSTOV, M D , Hughston Ortho1315 Delauney Avenue, Columbus, Georgia 31901I

JACK C

paedic Clinic, PC,

believe the anteromedial

surgical

approach to the knee provides the only adequate visualization and evaluation of the lateral meniscus. Lateral surgical approaches often commit the meniscus to removal before a tear can be a certainty and other associated and unanticipated pathol104

presents

a

method of

With proper retraction, the entire lateral meniscus can be visualized along with both compartments of the knee joint. The surgical technique of lateral memsectomy through this anteromedial approach, along with a secondary postero-lateral incision, is described. The merits of the anteromedial incision to evaluate the lateral meniscus were studied in 100 consecutive knees which required a

proach.

menisectomy. Sixty-one percent (61%) were participating in athletics at the time of their

Using this incision initially for menisectomies, we found a relatively high incidence of lateral meniscus tears (31 %). Seventeen percent (17%) had both medial initial injury.

all

and lateral meniscus tears. We also studied our clinical pre-operative

diagnosis

versus

Much to

our

strictly

on

our

our

operative diagnosis.

surprise, if

we

had relied

pre-operative diagnosis,

total of 36 abnormal

a

would have been missed. The anteromedial approach avoids this catastrophe as both the menisci are evaluated at the time of arthrotomy. This substantiates our recommendation that the initial surgical approach should be anteromedial, regardless of the pre-operative menisci

diagnosis. The Meniscus

as a

Cruciate

Ligament

Substitute

the Lateral Meniscus

We

relatively hidden. This paper evaluating the lateral meniscus through an anteromedial apremains

ogy

H

ROYER COLLIBS, M D , Head, Section of

Sports Medicine, Department of Orthopaedic Surgery, Cleveland Clinic, Cleveland, Ohio HUGHSTOB. M D , KE’~’vETH E DEM D, JOHN A. BERGFELD, M D, CHARLES M EVARTS, M.D., Cleveland Clmc, Cleveland, Ohio

JACK C

HAVE’B,

Te patient

with posterior cruciate ligadamage and/or anterior cruciate ligament damage has presented a problem to the orthopaedist for some time In our research, ment

four basic questions have been considered1 ) Do transferred, transplanted menisci be-

firmly attached to bone? 2) Do they become vasculanzed? 3) Do they undergo metaplasia toward a more ligamentous structure? 4) Do they attain sufficient strength? Eighteen adult mongrel dogs had 34 surgical procedures performed, with the come

cruciate

ligament being completely excised,

and the medial meniscus then being excised except for its anterior or postenor horn attachment. The meniscus was then attached to the femur, being drawn up through a drill hole made in the intercondylar notch at the site of origin of the cruciate ligament Postoperatively, these dogs were sacrificed and the ligaments tested for tensile strength and then examined histologically to answer the questions which were proposed. The menisci were found to attach to the bone, to become vasculanzed and appear to undergo meta-

plasia looking

more

went on in response to

ligamentous the

new

as time

defunctional

demand. Tensile strength compared very favorably with O’Donoghue’s studies in which he found the primary repair of the cruciate ligament in the dogs tested at 3 months ruptured at 79 to 100 pounds of stress with a rupture occurring at a reconstructed anterior cruciate ligament when 22 to 68 pounds of stress were applied. In our series, the transferred menisci were found to rupture when a stress of 75 to 89 pounds was placed upon it. In all cases in our series, the meniscus ruptured at its usual attachment at the tibia and didn’t pull loose at the femoral attachment, nor did rupture occur in the substance of the meniscus itself. The medial meniscus has been used as a graft for the posterior cruciate ligament in 10 cases, with good results in 7, failure in 2, and I patient being lost to follow-up. The average follow-up in these cases was 2.6 years with the shortest being I year and the longest being 5 years. Further investigation is necessary to answer questions regarding long-term results in animals and humans.

Osteochindntis Dissecans of the Capitellum Athletes

in

Young

ROBERT BROw, M.D, Orthopaedic Resident, White Memorial Hospital, Los Angeles, Cali-

form

An attempt

was made to recall 36 pawith a diagnosis of osteochindntis dissecans or osteochondral fracture of the capitellum. We were able to recall 21 patients. The other 15 we were unable to contact. Of these patients, 3 had sustained their injury from one traumatic episode The other 18 patients were involved in an organized athletic activity and the mechanism of injury appeared to be that of repetitive

tients

trauma

One was a 6’/2 year old tennis player who had been playing tennis 21/2hours a day, five days a week, for 11/z years with his father who was a tennis coach. 17 of these patients were baseball players. They were all boys, and the elbow involved was always the dominant, or throwing arm. The average age of onset of symptoms was 12.5 years. The average number of years involved in organized baseball prior to the onset of symptoms was 3.5 years. Average time interval from the time of onset of symptoms until first seen by physician was I year. 15 of the 17 patients went on to have elbow surgery and two patients required two surgeries. The average time from the onset of symptoms until surgery was 3.7 years Average follow up time since surgery in the 15 operative cases was 3 years. Average follow up time since surgery in the 15 post operative cases was 3 years. 13 of the 17 boys had been either a pitcher or a catcher. Only two of these 17 patients received the diagnosis of osteochondntis dissecans of the capitellum on their first physician visit. The average pre-operative examination showed 122 degrees of flexion and a 20 degree lack of complete extension. X-rays showed an ill-defined patchy decalcification and more commonly a radiolucent or cystic like area on the capitellum leading to a radiological diagnosis of osteochondntis dissecans of the capitellum. The radial head usually appeared to be involved showing irregularity, hypertrophy, and early epiphyseal closure starting on the radial side. At surgery, one or more loose bodies were removed from 13 of these elbow joints. The average time since surgery was 3 years. Average elbow motion was now 139 degrees 105

of flexion and 12 degrees from complete extension. Only one of these 17 patients has been able to return to repetitious hard throwing. 2 patients are able to throw some, but they do not throw hard and the remainder no longer throw in competetive sports. We cannot help but feel that the phenomenon known as osteochondritis dissecans of the capitellum in adolescent boys, is the end result of repetitive valgus stress, and impingement of the radial head against the

capitellum. The Pathology and Surgical Treatment of Partial Rupture of the Patellar Tendon in Athletes (Jumper’s Knee) FRANK H BASSETT, III, M D , Associate Professor of Orthopaedic Surgery, Duke University Medical Center, and team physician, Duke University, Durham, North Carolina.

the patient is conscious and can guide the surgeon to find the area of tenderness. The athletes presented with symptoms varying from less than six months to approximately four years. Two patients had symptoms less than six months duration. Their roentgenograms were normal, and the gross pathology consisted of brownish-yellow mucoid material surrounded by healthy tendon fibers. Histologically, the specimens showed loss of staining qualities of the involved tendon fibers. Five patients had symptoms lasting from six months to one year. Roentgenograms revealed focal decreased density in the inferior pole of the patella. Grossly the lesions appeared white; they were moderately firm. Histologically, additional loss of staining qualities were seen. Foci of capillary proliferation into the normally avascular areas of tendon were noted, indicating a reparative process.

Dr.

Frank H. Bassett, III, and Dr. Panayiotis Soucacos stated that repetitive and rapid acceleration and deceleration are ac-

tions required of athletes in many sports. These actions concentrate great stress on the patellar tendon, and, if forceful enough, may cause tearing of some or all of the fibers. The authors reported on 12 athletes with partial rupture of the deep fibers of the patellar tendon adjacent to the inferior margin of the patella. All were young adult males participating in intercollegiate or professional athletics. The syndrome is characterized by pain in the patellar tendon just below the inferior pole of the patella and is associated with particular athletic activities such as sudden stopping, jumping or rapid forceful acceleration. Otherwise, symptoms are absent with less demanding activities. Physical examination of the knee is usually negative except for an area of local tenderness in the involved area with the knee extended. Since non operative treatment fails to give lasting relief excision of the tender area of scar or granulation tissue is recommended under local anesthesia. Because of the small, circumscribed area of involvement, the identification of the pathology is difficult unless 106

Three patients had symptoms lasting from one year to two years. Roentgenograms showed an area of increased density in the patellar tendon adjacent to the inferior aspect of the patella with or without minimal calcification adjacent to the patella. Grossly the lesion resembled fibrocartilage tissue and calcification of the lesion was found. One patient had symptoms of four years duration. His roentgenogram revealed ossification in the patellar tendon adjacent to the patella. Grossly, the lesion was bony and could not be cut easily with the scalpel. Histologically, bone spicules were identified within the fibrocartilaginous matrix. These patients have been followed up to 12 years. Ten are pain free, one is improved but still has pain associated with rebounding and jumping, and one patient was not relieved. The authors feel that the primary pathology is that of a partial rupture of the deeper fibers of the patellar tendon and that with repetitive trauma associated with athletics the tendon fibers do not heal properly, but,

rather, undergo collagenous degenerative

changes

which lead to fibrocartilage metaplasia and, finally, to ossification in the area of the original injury. The authors recom-

mend excision of the area of involvement under local anesthesia as the treatment of choice.

The Effect of Local Steroid

Infections

on

Tendon L. J UNVERFERTH, M D , Columbus, Oh)0, MELVIN L. Onx, M.D., Columbus, Ohio.

It

is common

practice

to

AND

inject symptomatic

with

steroids. Five of tendon rupture following local steroid injections in athletic individuals are presented. The analysis of these cases leads one to believe that local steroid injection into and about tendon is harmful. To evaluate this supposition, a laboratory experiment was conducted on 18 rabbits. The gastroenemius tendons of these rabbits, when injected with steroid, demonstrated statistically lower moduli of elastic stiffness than similar tendons injected with saline. Thus, the tensile strength of the steroid injected tendons is less than the saline injected tendons.

tenosynovitis locally cases

as well as microscopic exof the steroid injected tendon demonstrate that marked inflammation and destruction is present, particularly about the pools of deposited steroid. Similar changes were not present in the saline injected tendons. A proposal is made to abandon the repeated use of local steroid injections in the treatment of tenosynovitis, particularly in athletic individuals.

Macroscopic

aminations

is of two and one half years duration. Of the 11cases involving tibial collateral substitution, three were associated with primary repairs and are all of good stability medially. The other eight cases involved reconstructive procedures with only one resulting in poor stability. Of the four cases involving tightening of the posteromedial corner, three were done at the time of primary repair and one as a reconstructive procedure with three of the four cases being of good stability medially. Functionally, all of these four cases were good. Functionally, the 11 cases involving tibial collateral substitution were good except where associated with a posterior drawer sign, or with posteromedial corner instability or a subluxating case

patella. This technique has not been successful on the lateral side of the knee. The importance of attaining medial stability is emphasized. The work of others using similar material for similar purposes is reviewed. The operative technique is described. A method of standardization of end results is presented. The use of Dacron tape in restoring stability to the medial side of the knee, on the basis of these early experiences, which will require the further test of time, offers hope for a simple, reasonably reliable, quick and convenient method for reinforcement of medial stability of the knee.

Blocking Injuries

at

the Knee Level

THOMAS R. PETERSON, M.D., Clinical Instructor, Department of Orthopaedic Surgery, University of Michigan School of Medicine, Ann

Arbor, Michigan.

Early Experiences in the Use of Dacron Tape Ligamentous Reinforcement About the

for

Knee LESLIE M. BODNAR, M.D., South Bend, Indiana.

Dacron

tape, 5 mm. wide, is used to reinforce either the longitudinal fibers of the tibial collateral ligament or the posteromedial corner of the knee in this early series of 15 patients. The longest experience with any

In previous reports by

the author, the cross block has been incriminated as a major body cause of knee injuries and the extreme injury problem related to the &dquo;crack back&dquo; block was identified. As a result, appropriate rules changes have decreased the problem of injuries due to the latter technique remarkably in the last two years at the collegiate level. The problem of the crack back block in injunes is still prominent at the professional level. 107

The continuing evaluation of knee injuries the University of Michigan, Michigan State University, and the Detroit Lions as well as with local high school teams in the Ann Arbor, Michigan area, has shown a consistently high percentage of knee injuries related to the external forces of blocking at the knee level. It is well documented in the statistical material and in the movie associated with this report that the greatest hazard to the knees on the football field at the present time is &dquo;blind side&dquo; blocking. This, of course, includes clipping which is illegal, but also many more injuries that are caused by blocking from the blind side that are judged to be legitimate technics. It can be quite well demonstrated that, in most instances, blocking from the blind side can be just as effective from the football standpoint if the block is carried out at a level above the waist. This technique is not likely to cause body injury for the most part and would further reduce the incidence of knee injuries. This report draws attention to the continuing high incidence of knee injuries to blocking of all types at the knee level, including the cross body block, shoulder blocking or spearing with the helmet. Elimination of this hazard will require some type of rules alteration which will limit blocking at the knee level at least in open field play. at

Achilles Tendon Problems

m

Athletics

E PAUL WOODWARD, M D., Assistant Clinical

Professor, Orthopedics Department of Surgery, University of California. San Diego

Dr.

Woodward discussed the following Achilles tendon problems in athletes. 1) Tenosynovitis and adhesive tendmtis. 2) Partial ruptures including strains of the tendon. 3) Complete rupture of the Achilles tendon. The anatomy of the Achilles tendon was thoroughly elucidated. The etiology of Achilles tendon rupture was studied, the author offering two explanations: 1) Rotation of the Achilles tendon causes a sawing effect where the fibers cross; 2) Patients 108

active

their

youth who later became less developed more sedentary activiexperienced muscular hypertrophy with in

active and

ties increased vasculanty of the muscle and tendon tissues in their youth and with decrease in activity experienced a decrease in vasculanty so that the tendons’ blood requirements were not met and degenerative change occurred. Strongly emphasized was the fact that local injection of steroid into an irritated Achilles tendon or into its surrounding area may be a factor in subsequent rupture in that it eliminates the patient’s warning system by ridding him of the pain, allowing him to return to the violent activities that might result in complete tendon rupture. The time honored squeeze or Thompson’s test remains an excellent test for the completely ruptured tendon; this sign will not be present in the partial rupture. Diagnosis of the partial rupture mcludes increased width of the tendon, increased dorsiflexion of the foot in at least one-third of the cases, muscle atrophy in over half of his cases, fusiform thickening of the tendon on palpation with a more indurated section near the rupture. The author points out that the basic aim of all treatment is to restore the length and continuity of the tendon and protect the anastamosis until healing is complete. In the athlete, where return to high performance is necessary, surgical repair which allows restoration of the tendon to its normal length is the best form of treatment. The tendon then must be protected for a minimum of eight weeks in a plaster cast with the foot in equinus and protected by a heel wedge for at least four weeks thereafter. Adhesive tendmtis and tenosynovitis and his treatment for these entities was discussed

briefly. Several very illustrative cast histories concluded the presentation. Seven patients with twelve tendons involved were presented. Three of his patients had had re-rupture of a previously repaired Achilles tendon. He made a strong point of the fact that out of fourteen cases treated surgically, seven had received cortisone prior to rupture or partial

rupture. The postoperative treatment

was

stan-

dard. There were minor complications in four cases with hematomas and superficial infections, none of which required additional surgery. On final result, the patients were all able to do one legged toe rises, one requiring a re-repair after postoperative disruption.

study was that the talar tilt angle by carefully hand stressing a freshly injured ankle without the use of any

from this obtained

local anesthetic or nerve block will be similar to that obtained under general anesthesia. The talar tilt measurements were identical when obtained in plantar or neutral

positions. The Pathomechamcs and Diagnosis of Inversion Injuries to the Lateral Ligaments of the Ankle

GLEN A fornia.

This

ALMQUIST, M D, Santa Ana, Cali-

paper concerns itself with the mechanism and sequence of ligament rupture as an aid to diagnosis. Three separate and distinct ligaments form the support on the lateral side of the ankle. These are: (1) The calcaneo-fibular ligament which is the longest of the three and is entirely extra capsular, (2) The anterior talo-fibular ligament which is the shortest of the three and is intra capsular and (3) the posterior talo-fibular ligament which is the strongest and the deepest of the three. The author studied the subject by doing anatomical dissections on forty freshly amputated lower extremities. With the prepared specimen fixed in a stress apparatus the following were measured: ( 1 ) Sequence of ligament rupture, (2) Angle of inversion needed for ligament rupture, (3) Force required for ligament rupture and (4) Anatomic areas of ligament rupture. Assuming that most injuries occur in the plantar-fixed position, the sequence of ligamentous interruptions would be the ante nor talo-fibular, the calcaneo-fibular and finally the posterior talo-fibular ligament. The ankle becomes grossly more unstable as each ligament is sectioned. The addition of a sectioned posterior talo-fibular ligament to the other two sectioned ligaments leads to frank dislocation. In stressing acutely injured patients, any patient with a talar tilt angle of greater than 7 degrees was given a general anesthetic and the tilt was measured again by hand and with tilting apparatus. Conclusion derived

Angles of from zero to 23 degrees have been given as normal; whereas, 6 degrees greater than the opposite side have been as diagnostic of total ligamentous tear. The author concludes that the anterior talo-fibular and calcaneo-fibular ligaments are the important ligaments in ankle sprains. With the ankle in neutral the calcaneo-fibular may rupture first or can rupture simultaneously with the anterior talofibular ligament. Rupture of the calcaneofibular alone is possible but as the foot is stable in the neutral position any sustained force would probably cause rupture of more than one hgament. In the plantar flexed position, which is the unstable position of the foot, the anterior talo-fibular will rupture first. Any talar tilt angle of twenty degrees or greater when compared with the normal side is pathognomonic of tear of both anterior talo-fibular and calcaneo-fibular ligament. Understanding the pathomechan~cs of ligamentous rupture of the lateral aspect of the ankle aids in establishing the diagnosis of ligamentous damage and proper management.

The

Orthopaedic Surgeon and the Olympic

Games J C. KENNEDY, M D, F R C S (C)., London, Ontario, Canada

Te author,

who served

as

the team

or-

thopaedist for the Canadian Olympic Association, reported a pictorial review of the Munich 1972 Olympics. He reported that the setting and facilities were outstanding and that orthopaedic disabilities were minimal. The Canadian medical quarters were in close proximity to the Israeli quarters, and 109

the author witnessed many of the events prior to the terrorists leaving the Olympic Village with Israeli hostages. Several constructive suggestions were made to improve future games, which included: the need for a permanent site to hold the Olympics, the return to individual events not requiring human judging, and the need to minimize the controversial and violence loaded team

sports.

Results of the Peona

High

School Football

Knee Injury Study BERNARD CAHILL, M.D , Peona, Illinois

From

1969 through 1972 a total of 1149 school football players received knee examinations by the author. The examination included demographic data, history of previous knee injury, and physical findings. Records of knee defects were kept and made available to each coach, emergency room, and team physician. Each knee injury, defined as one requiring the athlete to miss a minimum of two practice sessions, was reported to the author during each of the four years, and details of type of injury, condition of the playing field, time of year, general activity at time of injury, type play, type of cleat, and type of heel were recorded. Each of these data were analyzed by standard statistical analysis using a Chi-square 2 x 2 contingency table. The study revealed that most injuries occurred during the first three weeks of the season. Most injuries occurred on a dry field and most frequently in some type of running

high

play. The study further revealed that the player with a combination of &dquo;abnormalities&dquo; has a higher incidence of injury than any others who have no abnormalities. A single abnormality does not produce a significantly higher injury rate than &dquo;normal&dquo;. History of a previous injury alone does not prejudice toward a higher injury rate. However, the athlete with any single physical abnormality plus a history of a previous injury is the

110

player jury.

who will

statistically

sustain

an

in-

Biomechanics of Running-An Analysis Utilizing the Harmonics of Motion STANLEN L JAPES, M D, Eugene, Oregon, Senior Instructor in Orthopaedics, University of Oregon, School of Medicine

The

purpose of this

study

was

to

begin

to

which would allow the mathematical characterization of an individual’s running gait. The method included sequential photographs of two competitive runners with strobe lights fixed to the mastoid process and joint centers of the hip, knee, and ankle. The strobe lights were set to flash at known time intervals varying from 17 msec. to 33.5 msec. The photographs recorded the changing positions of the joint centers and the mastoid process. During a complete stride, each joint was exposed 27 to 39 times permitting a tracing of the movement of each marked joint. The data were reduced for analysis by plotting the two dimensional coordinates of the points which indicated their movement during a complete running stride. Stride characterization was accomplished by performing harmonic analysis on each of the four wave-like paths of motion recorded on a picture. Harmonic analysis is described as a mathematical method by which a complex, periodic, waveform is characterized in terms of one or more sine-waves. The fundamental sine-wave (first harmonic) was fitted and its deviation from the experimental waveform was determined via the least squares method. The second harmonic with a frequency equal to twice the fundamental’s was then added. Additional harmonics were added in numbers up to one half the number of data points. From mathematical equations, it was determined by this study that the first seven harmonics were considered to yield an adequate representation of the waveforms obtained.

develop

a

technique

First meeting of the American Orthopaedic Society for Sports Medicine.

Proceeding Highlights First Meeting of the American Orthopaedic Society for Sports Medicine Robert L. Larsen, M.D., Eugene, Oregon meeting of the Am...
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