- Email: [email protected]
A prevalence study of recurrent shoulder dislocations in young adults
A prevalence young Charles
study of recurrent
Milgrom,
Surg
MD,
Gideon
Mann{
MD,
and Aharon
1998;7:62
l-4)
Th e concept of performing arthroscopic shoulder surgery after a first >houlder dislocation to limit recurrences is currently being popularized.1,” To iudge whether
this
approach
lation,
it is important
recurrent With elius
shoulder a method
interviewed
is justified
for
to understand
the
dislocations. of representative
2092
people
general
popu-
the epidemiology
of
sampling,
ranging
Hov-
in age from
18 and 70 years and determined the shoulder dislocation rate in the general Swedish population to be 1.7% and the reoccurrence rate to be 20%. In a subsequent prospective study, Hovelius* determined that 60% of 20-year-olds had more than 1 subsequent dislocation after their initial shoulder dislocation. From
the
School MedIcal Presented
Hadassah
Umverslty
Hospftal
of Medlclne, Jerusalem Corps, Israel In part
Academy 26,
and
at the S~xtyth~rd
of Orthopaedlc
Annual
Surgeons,
ond the
Hebrew
Israel1
Meeting Atlantu,
Unlverslty
Defense
Forces
of the American Ga,
February
22-
1996
Reprint requests, C Mllgrom, MD, Hadassah Umverslty Hospital, jerusalem 91120, Israel Copyright Board
dislocations
in
adults
The computerized database of the Israeli Detknce Forces Medical Corps monitors recurrent shoulder dislocations before citizens are eligible for military induction, during the years of regular military service, and during the time of e/igibility for reserve army service. With the computerized database of the Israeli Defence Forces Medical Corps, between the years of 1978 to 1995 the prevalence rate of subjects with recurrent shoulder dislocations less than or equa/ to 2 1 years of age was found to be 19.7 of 10,000 for men and 5.0 1 of 10,000 for women. The prevalence rate of subjects with a history of shoulder dislocations in the ma/e populafion between the ages of 22 and A? years was 42.4 of 10,000. Forfy-four percent were judged fo be sufficiently unstable to warrant surgery, but only 55% of these actually underwent surgery. These epidemiologic data may be important if arthroscopic shoulder surgery is being considered after a first shoulder dislocation. (J Shoulder Elbow
shoulder
0 1998 of Trustees
10%2746,/98/$5
by Journal 00 + 0
Department Ejn Kerem,
of Shoulder
32/l/901
00
and
of Orthopaedlcs, POEox 12000( Elbow
Surgery
Finestone,
MD, Jerusalem,
Israel
In Israel an ongoing computerized health database of all citizens eligible for the draft is kept by the Israel Defence Forces Medical Corps. This database is continually updated throughout the years during which a citizen is eligible for regular and reserve army service. With this database we undertook to determine the prevalence of subiects with recurrent shoulder dislocations in the young adult Israeli male and female populations
and
surgery
and of those who
MATERIALS
the
AND
prevalence
of
those
underwent
indicated
for
surgery.
METHODS
All male and female Jewish citizens of the State of Israel and male Druze are subiect to military draft. All those who are eligible for the draft must report before possible military induction for a screening that includes a physical examination and a detailed history of health problems. By law they must make a full disclosure of all of their past health problems and supply documentation when available; the data are computerized. Recurrent shoulder dislocaters are coded according to 4 classifications: (1) infrequent dislocations or more than 1 -year status after surgery with mild instability; (2) f re q uent dislocations; (3) less than I-year status after surgery; and (41 l-year status after surgery with a stable shoulder. A computer code is assigned only after the subject has had a second dislocation and has appeared before a medical board that performs a physical examination and reviews supporting documents including radiograms and medical letters. During military service shoulder instability problems are continually monitored. Care for a shoulder instability problem can be given only by the military. Recurrent shoulder dislocators receive a computerized code only after the soldier has been presented to the medical board. During the years that citizens are eligible for reserve army service, shoulder dislocators are similarly monitored and coded. This database allows calculation of the number of subiects with recurrent shoulder dislocations that are present at any point in time. In epidemiology such a calculation is referred to as the prevalence. With the computerized health database of the IDF, from 1978 to 1994 the following prevalence rates were calculated from the population between the ages of 22 and 33 years as of December 1994. Group 1: the prevalence of recurrent shoulder dislocators in the male population before and at the time of induction into the IDF (mean age 18.7). Group 2: the prevalence of new, recurrent shoulder dislocators in the male po ulation between the ages of 18.7 and 21 years during t IYe period of their regular arm service. Group 3: the prevalence of new, recurrent shou- T der dislocators in the male population during the period of reserve army service eligibility between the ages of 22
621
622
Milgrom,
Mann,
and Finestone
J Shoulder November/December
Elbow
Surg 1998
18.7-21 Me
Figure
1 Prevalence
of shoulder
dislocators
in young
male
2 Prevalence
of shoulder
according
to age
of onset.
female
male Figure
adults
dislocators
and 33 years. Group 4: the prevalence of past or present recurrent shoulder dislocators in the male population ages 22 to 33 years. Group 5: the prevalence of recurrent shoulder dislocators among men less than or equal to 21 ears. Group 6: the prevalence of recurrent shoulder disr ocators among women less than or equal to 21 years. For each male age group the percentage of those with recurrent dislocations who underwent surgery, those who were indicated for surgery but did not undergo surgery, and those who were not iudged to have sufficient symptoms to warrant surgery was calculated.
according
to sex
(age
521
years).
tions according to groups 1, 2, and 3 with their clinical outcome according to the percentage of those who had infrequent instability not warranting surgery, the percentage who underwent surgery, and those who were indicated for surgery but chose not to undergo surgery. The overall prevalence of recurrent shoulder dislocators, both past and present for the male population aged 22 to 33 years (group 4), was 42.2 of 10,000; 24% underwent surgery, and an additional 20% were indicated for surgery but did not undergo surgery.
RESULTS Figure 1 compares the prevalence rates per 10,000 of recurrent shoulder dislocators for men according to their age at onset according to groups 1, 2, and 3. The highest prevalence rate was during active military service, between the ages of 18.7 and 21 years. Figure 2 compares the prevalence rate of recurrent shoulder dislocators for men (group 5) and women (group 6) less than or equal to 21 years of age. The male prevalence was nearly 6 times the female. Figure 3 compares the age of onset of recurrent shoulder disloca-
DISCUSSION The proposal to offer early surgery to prevent recurrence after a primary traumatic shoulder dislocation is not new. In 1942 Nicola* advocated it as the only effective means to heal the disrupted shoulder ioint supports after a primary shoulder dislocation and to prevent subsequent recurrent dislocations. in 1950 McLaughlin and Cavallaro7 supported Nicola’s* view. Rowe,9 in a retrospective study based on admissions to Massachusetts General Hospital over a 20-year period for shoulder dislocation, documented that recurrent
Milgrom,
j Shoulcfer Elbow Surg Volume 7, i’dumber 6
Mann,
q Infrequent
and Finestone
623
instability
0 4 8.7
22-33
18.7-21
Age at onset Figure
3 Age
at onset
of recurrent
shoulder
shoulder dislocation rates are age-dependent. He found that 83% of primary shoulder dislocations in patients under the age of 20 years, 63% of those in patients between the ages of 20 and 40 years, and only 16% of those in patients older than 40 years had reoccurrences. Rowe9 did not, however, support surgery after a primary shoulder dislocation, because “a large number of these will be symptom-free and will have very good shoulders until there is a recurrence.” In 1961 Rowe and Sakellarideslu reported a continuation of Rowe’s9 initial study with expanded but largely unchanged results. In a prospective study Hovelius3 determined that 60% of 20year-olds had more than 1 subsequent dislocation after their initial shoulder dislocation. This study represents the first large population prospective prevalence study of recurrent shoulder dislocators reported. It is based on the IDF Medical Corps computerized database between the years 1980 to 1995. The number of subiects in the database is large, but because of military security reasons only prevalence rates per 10,000 are reported. Medical followup of the subiects in this database was strict, as were the criteria for classifying a person as a recurrent dislocator. In this study of a population of Israelis of mixed ancestry, the prevalence of subjects with past or present recurrent dislocations in the male population 22 to 33 years old (those after the age of regular military service) was found to be approximately 0.5%. in approximately half of the cases the degree of instability in this age group was judged to warrant surgery by a senior orthopaedic surgeon. However, only 55% of those indicated for surgery in fact underwent surgery. During the 3 years of regular army service, relatively few soldiers underwent surgery because they usually did not want to interrupt their military service by surgery and the subsequent rehabilitation period.
dislocations
versus
clinical
outcome.
In this study the highest prevalence of male recurrent shoulder dislocations (19.7 of 10,000) occurred during the time of regular military service (ages 18 to 21 years). This result may reflect the increased physical activity level and exposure to trauma during the period. reported a 1 .7% incidence of Although Hoveliuss shoulder dislocators in the general Swedish population between the ages of 18 and 70 years, he found an 8% incidence of shoulder dislocations in top league Swedish ice hockey players.4 The 6:l male to female prevalence ratio of recurrent shoulder dislocators found in this study may also reflect the importance of trauma in the cause. The epidemiologic data of this study are important when arthroscopic surgery is being considered as a treatment to prevent recurrent dislocations after a first traumatic shoulder dislocation.‘,’ 1 Advocating this treatment for the general young population would not seem to be warranted, because three fourths of subjects between the ages of 22 and 33 years in this study with a history of shoulder dislocations had not undergone surgery in a follow-up ranging from 1 to 16 years. At this age the subjects were beyond their compulsory military service and had no obvious secondary gain in deferring their surgery. Hovelius et aI,5 on the basis of their 1 O-year follow-up of primary anterior dislocation of the shoulder in young adults, likewise conclude that routine prophylactic operative treatment even for the youngest age group with primary shoulder dislocations is not warranted. The approach of immediate surgical stabilization after the first shoulder dislocation, however, may be applicable for special subpopulations. REFERENCES 1
Arcfero Bankart
RA, Wheeler repaIr versus
JH, Ryan 16, McBride nonoperatlve treatment
JT Arthroscoplc for acute, initial
624
2
Milgrom,
Mann,
J Shoulder Elbow Surg November/December J998
and Finestone
anterfor shoulder dislocations Am J Sports Med 1994,22 589-94 Hovellus t Anterior dlslocatfon of the shoulder in teen-agers and young adults Five-year prognox J Bone Joint Surg Am 1987,69A 393-9
3
Hoveijus Orthop
4
Hovejlus t Shoulder dislocations In Swedish I-S hockey players Am J Sports Med 1978,6 373-7 Hovejlus t, AugustIn BG, FredIn H, Johansson 0, Norlln R, Thorlfng J Primary anterior dlslocatfon of the shoulder m young patients A ten-year prospective study .I Bone Joint Surg 1996,78A 1677-84
5
t, lncjdence of shoulder 1982,166 127-3 1
dlslocatfon
In Sweden
RECEIVE THE JOURNAL’S
6 7
Kazar B, Relovszky E Prognox of primary dlslocatlon of the shoulder Acta Orthop Stand 1969,40 2 16-24 Mctaughlln Ht, Cavallaro WU Primary anterior dlslocatlon of the shoulder. Am 1 Surg 19.50,80 6 15-2 1
8
Nlcola anterior
9
Rowe CR Prognosis It- dlslocatlons of the shoulder J Bone Joint Surg Am 1956,38A 9.57-77 Rowe CR, Sakellarldes HT Factors related to recurrences of anterior dlslocatjons of the shoulder Clan Orthop 1961,20 40-7 Urlbe JW, Hechtman KS Arthroscoplcally assIsted repaIr of acute Bankart lesson Orthopedics 1 993J 16 1019-23
Clan
10
11
TABLE OF CONTENTS
T Anterior dlslocatlon capsule J Bone Joint
EACH MONTH
of the shoulder The role of the Surg Am 1942,24A 614-6
BY E-MAIL
To receive the tables of contents by e-mail, send an e-mail message to [email protected] Leave the subject line blank, and type the following Subscribe s&e-tot
as the body of your message:
You can also sign up through our website at http:/lwww.mosby.com/s&e. You will receive an e-mail message confirming that you have been added to the mailing list. Note that TOC e-mails will be sent when a new issue is posted to the website.
study of recurrent
Milgrom,
Surg
MD,
Gideon
Mann{
MD,
and Aharon
1998;7:62
l-4)
Th e concept of performing arthroscopic shoulder surgery after a first >houlder dislocation to limit recurrences is currently being popularized.1,” To iudge whether
this
approach
lation,
it is important
recurrent With elius
shoulder a method
interviewed
is justified
for
to understand
the
dislocations. of representative
2092
people
general
popu-
the epidemiology
of
sampling,
ranging
Hov-
in age from
18 and 70 years and determined the shoulder dislocation rate in the general Swedish population to be 1.7% and the reoccurrence rate to be 20%. In a subsequent prospective study, Hovelius* determined that 60% of 20-year-olds had more than 1 subsequent dislocation after their initial shoulder dislocation. From
the
School MedIcal Presented
Hadassah
Umverslty
Hospftal
of Medlclne, Jerusalem Corps, Israel In part
Academy 26,
and
at the S~xtyth~rd
of Orthopaedlc
Annual
Surgeons,
ond the
Hebrew
Israel1
Meeting Atlantu,
Unlverslty
Defense
Forces
of the American Ga,
February
22-
1996
Reprint requests, C Mllgrom, MD, Hadassah Umverslty Hospital, jerusalem 91120, Israel Copyright Board
dislocations
in
adults
The computerized database of the Israeli Detknce Forces Medical Corps monitors recurrent shoulder dislocations before citizens are eligible for military induction, during the years of regular military service, and during the time of e/igibility for reserve army service. With the computerized database of the Israeli Defence Forces Medical Corps, between the years of 1978 to 1995 the prevalence rate of subjects with recurrent shoulder dislocations less than or equa/ to 2 1 years of age was found to be 19.7 of 10,000 for men and 5.0 1 of 10,000 for women. The prevalence rate of subjects with a history of shoulder dislocations in the ma/e populafion between the ages of 22 and A? years was 42.4 of 10,000. Forfy-four percent were judged fo be sufficiently unstable to warrant surgery, but only 55% of these actually underwent surgery. These epidemiologic data may be important if arthroscopic shoulder surgery is being considered after a first shoulder dislocation. (J Shoulder Elbow
shoulder
0 1998 of Trustees
10%2746,/98/$5
by Journal 00 + 0
Department Ejn Kerem,
of Shoulder
32/l/901
00
and
of Orthopaedlcs, POEox 12000( Elbow
Surgery
Finestone,
MD, Jerusalem,
Israel
In Israel an ongoing computerized health database of all citizens eligible for the draft is kept by the Israel Defence Forces Medical Corps. This database is continually updated throughout the years during which a citizen is eligible for regular and reserve army service. With this database we undertook to determine the prevalence of subiects with recurrent shoulder dislocations in the young adult Israeli male and female populations
and
surgery
and of those who
MATERIALS
the
AND
prevalence
of
those
underwent
indicated
for
surgery.
METHODS
All male and female Jewish citizens of the State of Israel and male Druze are subiect to military draft. All those who are eligible for the draft must report before possible military induction for a screening that includes a physical examination and a detailed history of health problems. By law they must make a full disclosure of all of their past health problems and supply documentation when available; the data are computerized. Recurrent shoulder dislocaters are coded according to 4 classifications: (1) infrequent dislocations or more than 1 -year status after surgery with mild instability; (2) f re q uent dislocations; (3) less than I-year status after surgery; and (41 l-year status after surgery with a stable shoulder. A computer code is assigned only after the subject has had a second dislocation and has appeared before a medical board that performs a physical examination and reviews supporting documents including radiograms and medical letters. During military service shoulder instability problems are continually monitored. Care for a shoulder instability problem can be given only by the military. Recurrent shoulder dislocators receive a computerized code only after the soldier has been presented to the medical board. During the years that citizens are eligible for reserve army service, shoulder dislocators are similarly monitored and coded. This database allows calculation of the number of subiects with recurrent shoulder dislocations that are present at any point in time. In epidemiology such a calculation is referred to as the prevalence. With the computerized health database of the IDF, from 1978 to 1994 the following prevalence rates were calculated from the population between the ages of 22 and 33 years as of December 1994. Group 1: the prevalence of recurrent shoulder dislocators in the male population before and at the time of induction into the IDF (mean age 18.7). Group 2: the prevalence of new, recurrent shoulder dislocators in the male po ulation between the ages of 18.7 and 21 years during t IYe period of their regular arm service. Group 3: the prevalence of new, recurrent shou- T der dislocators in the male population during the period of reserve army service eligibility between the ages of 22
621
622
Milgrom,
Mann,
and Finestone
J Shoulder November/December
Elbow
Surg 1998
18.7-21 Me
Figure
1 Prevalence
of shoulder
dislocators
in young
male
2 Prevalence
of shoulder
according
to age
of onset.
female
male Figure
adults
dislocators
and 33 years. Group 4: the prevalence of past or present recurrent shoulder dislocators in the male population ages 22 to 33 years. Group 5: the prevalence of recurrent shoulder dislocators among men less than or equal to 21 ears. Group 6: the prevalence of recurrent shoulder disr ocators among women less than or equal to 21 years. For each male age group the percentage of those with recurrent dislocations who underwent surgery, those who were indicated for surgery but did not undergo surgery, and those who were not iudged to have sufficient symptoms to warrant surgery was calculated.
according
to sex
(age
521
years).
tions according to groups 1, 2, and 3 with their clinical outcome according to the percentage of those who had infrequent instability not warranting surgery, the percentage who underwent surgery, and those who were indicated for surgery but chose not to undergo surgery. The overall prevalence of recurrent shoulder dislocators, both past and present for the male population aged 22 to 33 years (group 4), was 42.2 of 10,000; 24% underwent surgery, and an additional 20% were indicated for surgery but did not undergo surgery.
RESULTS Figure 1 compares the prevalence rates per 10,000 of recurrent shoulder dislocators for men according to their age at onset according to groups 1, 2, and 3. The highest prevalence rate was during active military service, between the ages of 18.7 and 21 years. Figure 2 compares the prevalence rate of recurrent shoulder dislocators for men (group 5) and women (group 6) less than or equal to 21 years of age. The male prevalence was nearly 6 times the female. Figure 3 compares the age of onset of recurrent shoulder disloca-
DISCUSSION The proposal to offer early surgery to prevent recurrence after a primary traumatic shoulder dislocation is not new. In 1942 Nicola* advocated it as the only effective means to heal the disrupted shoulder ioint supports after a primary shoulder dislocation and to prevent subsequent recurrent dislocations. in 1950 McLaughlin and Cavallaro7 supported Nicola’s* view. Rowe,9 in a retrospective study based on admissions to Massachusetts General Hospital over a 20-year period for shoulder dislocation, documented that recurrent
Milgrom,
j Shoulcfer Elbow Surg Volume 7, i’dumber 6
Mann,
q Infrequent
and Finestone
623
instability
0 4 8.7
22-33
18.7-21
Age at onset Figure
3 Age
at onset
of recurrent
shoulder
shoulder dislocation rates are age-dependent. He found that 83% of primary shoulder dislocations in patients under the age of 20 years, 63% of those in patients between the ages of 20 and 40 years, and only 16% of those in patients older than 40 years had reoccurrences. Rowe9 did not, however, support surgery after a primary shoulder dislocation, because “a large number of these will be symptom-free and will have very good shoulders until there is a recurrence.” In 1961 Rowe and Sakellarideslu reported a continuation of Rowe’s9 initial study with expanded but largely unchanged results. In a prospective study Hovelius3 determined that 60% of 20year-olds had more than 1 subsequent dislocation after their initial shoulder dislocation. This study represents the first large population prospective prevalence study of recurrent shoulder dislocators reported. It is based on the IDF Medical Corps computerized database between the years 1980 to 1995. The number of subiects in the database is large, but because of military security reasons only prevalence rates per 10,000 are reported. Medical followup of the subiects in this database was strict, as were the criteria for classifying a person as a recurrent dislocator. In this study of a population of Israelis of mixed ancestry, the prevalence of subjects with past or present recurrent dislocations in the male population 22 to 33 years old (those after the age of regular military service) was found to be approximately 0.5%. in approximately half of the cases the degree of instability in this age group was judged to warrant surgery by a senior orthopaedic surgeon. However, only 55% of those indicated for surgery in fact underwent surgery. During the 3 years of regular army service, relatively few soldiers underwent surgery because they usually did not want to interrupt their military service by surgery and the subsequent rehabilitation period.
dislocations
versus
clinical
outcome.
In this study the highest prevalence of male recurrent shoulder dislocations (19.7 of 10,000) occurred during the time of regular military service (ages 18 to 21 years). This result may reflect the increased physical activity level and exposure to trauma during the period. reported a 1 .7% incidence of Although Hoveliuss shoulder dislocators in the general Swedish population between the ages of 18 and 70 years, he found an 8% incidence of shoulder dislocations in top league Swedish ice hockey players.4 The 6:l male to female prevalence ratio of recurrent shoulder dislocators found in this study may also reflect the importance of trauma in the cause. The epidemiologic data of this study are important when arthroscopic surgery is being considered as a treatment to prevent recurrent dislocations after a first traumatic shoulder dislocation.‘,’ 1 Advocating this treatment for the general young population would not seem to be warranted, because three fourths of subjects between the ages of 22 and 33 years in this study with a history of shoulder dislocations had not undergone surgery in a follow-up ranging from 1 to 16 years. At this age the subjects were beyond their compulsory military service and had no obvious secondary gain in deferring their surgery. Hovelius et aI,5 on the basis of their 1 O-year follow-up of primary anterior dislocation of the shoulder in young adults, likewise conclude that routine prophylactic operative treatment even for the youngest age group with primary shoulder dislocations is not warranted. The approach of immediate surgical stabilization after the first shoulder dislocation, however, may be applicable for special subpopulations. REFERENCES 1
Arcfero Bankart
RA, Wheeler repaIr versus
JH, Ryan 16, McBride nonoperatlve treatment
JT Arthroscoplc for acute, initial
624
2
Milgrom,
Mann,
J Shoulder Elbow Surg November/December J998
and Finestone
anterfor shoulder dislocations Am J Sports Med 1994,22 589-94 Hovellus t Anterior dlslocatfon of the shoulder in teen-agers and young adults Five-year prognox J Bone Joint Surg Am 1987,69A 393-9
3
Hoveijus Orthop
4
Hovejlus t Shoulder dislocations In Swedish I-S hockey players Am J Sports Med 1978,6 373-7 Hovejlus t, AugustIn BG, FredIn H, Johansson 0, Norlln R, Thorlfng J Primary anterior dlslocatfon of the shoulder m young patients A ten-year prospective study .I Bone Joint Surg 1996,78A 1677-84
5
t, lncjdence of shoulder 1982,166 127-3 1
dlslocatfon
In Sweden
RECEIVE THE JOURNAL’S
6 7
Kazar B, Relovszky E Prognox of primary dlslocatlon of the shoulder Acta Orthop Stand 1969,40 2 16-24 Mctaughlln Ht, Cavallaro WU Primary anterior dlslocatlon of the shoulder. Am 1 Surg 19.50,80 6 15-2 1
8
Nlcola anterior
9
Rowe CR Prognosis It- dlslocatlons of the shoulder J Bone Joint Surg Am 1956,38A 9.57-77 Rowe CR, Sakellarldes HT Factors related to recurrences of anterior dlslocatjons of the shoulder Clan Orthop 1961,20 40-7 Urlbe JW, Hechtman KS Arthroscoplcally assIsted repaIr of acute Bankart lesson Orthopedics 1 993J 16 1019-23
Clan
10
11
TABLE OF CONTENTS
T Anterior dlslocatlon capsule J Bone Joint
EACH MONTH
of the shoulder The role of the Surg Am 1942,24A 614-6
BY E-MAIL
To receive the tables of contents by e-mail, send an e-mail message to [email protected] Leave the subject line blank, and type the following Subscribe s&e-tot
as the body of your message:
You can also sign up through our website at http:/lwww.mosby.com/s&e. You will receive an e-mail message confirming that you have been added to the mailing list. Note that TOC e-mails will be sent when a new issue is posted to the website.