Isokinetic strength of fully operational U.S. Navy Seals with a previous history of shoulder and knee injury

Abstract

BACKGROUND:

Unintentional musculoskeletal injury has a significant impact on military personnel which is amplified in U.S. Navy Sea, Air, and Land Operators who participate in year round physical and tactical training. Full recovery from injury including restoration of strength is necessary for safe participation in training and performance of missions. Inadequate recovery may predispose the Operator to risk of future injury.

OBJECTIVE:

The purpose of this study was to examine isokinetic knee and shoulder strength of previously injured Operators who had returned to full duty.

METHODS:

Two previously injured cohorts, a knee injury group(n = 46) and a shoulder injury group (n = 55), were created from a larger group of Operators (n = 305) who had undergone strength testing. A comparison cohort was also created from each injury group (knee injury control group (n = 77) and shoulder injury control group (n = 121). All participants underwent isokinetic strength testing of their group assigned joint. This included knee flexion/extension strength testing for the knee group and shoulder internal/external rotation strength testing for the shoulder group. Side-to-side comparisons were made within each injury group and to the control group (injured extremity to strongest extremity of the control group). Individual counts within the injured Operators with strength deficits greater than 10% in their injured extremity were also performed.

RESULTS:

No significant side-to-side or between group differences were observed for the knee injury group. No significant side-to-side or between group differences were observed except for shoulder external rotation strength which was significantly different between groups(p = 0.003). Side-to-side strength deficits greater than 10% were observed in 20 to 25% of the injured Operators.

CONCLUSION:

The group comparisons demonstrate the effectiveness of the military group's rehabilitation and performance training programs, but continued vigilance and tracking of injured individuals are necessary to insure full recovery and return to duty as a small number of each injured cohort did have strength deficits bilaterally.

Keywords

Injury prevention shoulder knee isokinetic strength navy SEALs

References

Garamone

. Reducing Sports Injuries http: //www.defense. gov2001, [updated Mar 27; cited 2015 April 20, 2015]. Available from: http: //www.defense.gov/news/newsarticle.aspx?id =457ww53.

Jones

, Perrotta

, Canham-Chervak

, Nee

, Brundage

. Injuries in the military: a review and commentary focused on prevention. American Journal of Preventive Medicine. 2000; 18(3): 71-84.

Kelley

, United States. Dept. of the Army. Office of the Surgeon General. Military preventive medicine: mobilization and deployment. Washington, D.C.: Borden Institute, Walter Reed Army Medical Center; 2003.

Lauder

, Baker

, Smith

, Lincoln

. Sports and physical training injury hospitalizations in the army. American Journal of Preventive Medicine. 2000; 18(3): 118-28.

Litow

, Krahl

. Public health potential of a disability tracking system: Analysis of U.S. navy and marine corps physical evaluation boards 2005-2006. Military Medicine. 2007; 12: 1270-4.

Popovich

, Gardner

, Potter

, Knapik

, Jones

. Effect of rest from running on overuse injuries in army basic training. American Journal of Preventive Medicine. 2000; 18(3): 147-55.

Smith

, Dannenberg

, Amoroso

. Hospitalization due to injuries in the military. Evaluation of current data and recommendations on their use for injury prevention. American Journal of Preventive Medicine. 2000; 18(3): 41-53.

Songer

, LaPorte

. Disabilities due to injury in the military. American Journal of Preventive Medicine. 2000; 18(3): 33-40.

Abt

, Sell

, Lovalekar

, Keenan

, Bozich

, Morgan

, et al. Injury epidemiology of U.S. army special operations forces. Mil Med. 2014; 179(10): 1106-12.

10.

Cameron

, Mountcastle

, Nelson

, DeBerardino

, Duffey

, Svoboda

, et al. History of shoulder instability and subsequent injury during four years of follow-up: A survival analysis. J Bone Joint Surg Am. 2013; 95(5): 439-45.

11.

Greene

, Cholewicki

, Galloway

, Nguyen

, Radebold

. A history of low back injury is a risk factor for recurrent back injuries in varsity athletes. Am J Sports Med. 2001; 29(6): 795-800.

12.

Hagglund

, Walden

, Ekstrand

. Risk factors for lower extremity muscle injury in professional soccer: The UEFA injury study. Am J Sports Med. 2013; 41(2): 327-35.

13.

Hill

, Kay

, Wahi

, McKinnon

, Bulathsinhala

, Haley

. Rates of knee injury in the U.S. active duty army, 2000-2005. Mil Med. 2012; 177(7): 840-4.

14.

Nilstad

, Andersen

, Bahr

, Holme

, Steffen

. Risk factors for lower extremity injuries in elite female soccer players. Am J Sports Med. 2014; 42(4): 940-8.

15.

Richmond

, Fukuchi

, Ezzat

, Schneider

, Emery

. Are joint injury, sport activity, physical activity, obesity, or occupational activities predictors for osteoarthritis? A systematic review. J Orthop Sports Phys Ther. 2013; 43(8): 515-B19.

16.

Robinson

, Seah

, Akhtar

. The epidemiology, risk of recurrence, and functional outcome after an acute traumatic posterior dislocation of the shoulder. J Bone Joint Surg Am. 2011; 93(17): 1605-13.

17.

Wilkinson

, Blacker

, Richmond

, Horner

, Rayson

, Spiess

, et al. Injuries and injury risk factors among British army infantry soldiers during predeployment training. Inj Prev. 2011; 17(6): 381-7.

18.

Riemann

, Lephart

. The sensorimotor system, Part I. The physiologic basis of functional joint stability. Journal of Athletic Training. 2002; 37(1): 71-9.

19.

Solomonow

, Krogsgaard

. Sensorimotor control of knee stability: A review. Scand J Med Sci Sports. 2001; 11(2): 64-80.

20.

Johansson

, Sjolander

. The neurophysiology of joints. In: Wright

, Radin

, editors. Mechanics of Joints: Physiology, Pathophysiology, and Treatment. New York, NY: Marcel Dekker Inc.; 1993; p. 243-90.

21.

Lew

, Lewis

, Craig

. Stabilization by capsule, ligaments, and labrum: stability at the extremes of motion. In: Matsen

, Fu

, Hawkins

, editors. The Shoulder: A Balance of Mobility and Stability. Rosemont, IL: American Academy of Orthopaedic Surgeons; 1993; p. 69-89.

22.

Lephart

, Henry

. The Physiological Basis for Open and Closed Kinetic Chain Rehabilitation for the Upper Extremity. Journal of Sport Rehabilitation. 1996; 5(1): 71-87.

23.

Swanik

, Lephart

, Giannantonio

, Fu

. Reestablishing Proprioception and Neuromuscular Control in the ACL-Injured Athlete. Journal of Sport Rehabilitation. 1997; 6: 182-206.

24.

Nagai

, Sell

, House

, Abt

, Lephart

. Knee proprioception and strength are correlated with landing kinematics during a single-leg stop-jump task. Journal of Athletic Training. (In Press).

25.

Croisier

, Ganteaume

, Binet

, Genty

, Ferret

. Strength imbalances and prevention of hamstring injury in professional soccer players: a prospective study. Am J Sports Med. 2008; 36(8): 1469-75.

26.

Edouard

, Degache

, Oullion

, Plessis

, Gleizes-Cervera

, Calmels

. Shoulder strength imbalances as injury risk in handball. Int J Sports Med. 2013; 34(7): 654-60.

27.

Schmitt

, Paterno

, Hewett

. The impact of quadriceps femoris strength asymmetry on functional performance at return to sport following anterior cruciate ligament reconstruction. J Orthop Sports Phys Ther. 2012; 42(9): 750-9.

28.

Sugiura

, Saito

, Sakuraba

, Sakuma

, Suzuki

. Strength deficits identified with concentric action of the hip extensors and eccentric action of the hamstrings predispose to hamstring injury in elite sprinters. J Orthop Sports Phys Ther. 2008; 38(8): 457-64.

29.

Myer

, Ford

, Barber Foss

, Liu

, Nick

, Hewett

. The relationship of hamstrings and quadriceps strength to anterior cruciate ligament injury in female athletes. Clin J Sport Med. 2009; 19(1): 3-8.

30.

Baumhauer

, Alosa

, Renstrom

, Trevino

, Beynnon

. A prospective study of ankle injury risk factors. Am J Sports Med. 1995; 23(5): 564-70.

31.

Sapega

. Muscle performance evaluation in orthopaedic practice. J Bone Joint Surg Am. 1990; 72(10): 1562-74.

32.

Schmitt

, Paterno

, Ford

, Myer

, Hewett

. Strength Asymmetry and Landing Mechanics at Return to Sport after Anterior Cruciate Ligament Reconstruction. Med Sci Sports Exerc. 2015; 47(7): 1426-34.

33.

Boling

, Padua

, Marshall

, Guskiewicz

, Pyne

, Beutler

. A prospective investigation of biomechanical risk factors for patellofemoral pain syndrome: the Joint Undertaking to Monitor and Prevent ACL Injury (JUMP-ACL) cohort. Am J Sports Med. 2009; 37(11): 2108-16.

34.

Leetun

, Ireland

, Willson

, Ballantyne

, Davis

. Core stability measures as risk factors for lower extremity injury in athletes. Med Sci Sports Exerc. 2004; 36(6): 926-34.

35.

Stensrud

, Risberg

, Roos

. Knee function and knee muscle strength in middle-aged patients with degenerative meniscal tears eligible for arthroscopic partial meniscectomy. Br J Sports Med. 2014; 48(9): 784-8.

36.

Grindem

, Eitzen

, Engebretsen

, Snyder-Mackler

, Risberg

. Nonsurgical or Surgical Treatment of ACL Injuries: Knee Function, Sports Participation, and Knee Reinjury: The Delaware-Oslo ACL Cohort Study. J Bone Joint Surg Am. 2014; 96(15): 1233-41.

37.

O'Sullivan

, O'Ceallaigh

, O'Connell

, Shafat

. The relationship between previous hamstring injury and the concentric isokinetic knee muscle strength of Irish Gaelic footballers. BMC Musculoskelet Disord. 2008; 9: 30.

38.

Edouard

, Degache

, Beguin

, Samozino

, Gresta

, Fayolle-Minon

, et al. Rotator cuff strength in recurrent anterior shoulder instability. J Bone Joint Surg Am. 2011; 93(8): 759-65.

39.

Erol

, Ozcakar

, Celiker

. Shoulder rotator strength in patients with stage I-II subacromial impingement: relationship to pain, disability, and quality of life. J Shoulder Elbow Surg. 2008; 17(6): 893-7.

40.

Meller

, Krettek

, Gosling

, Wahling

, Jagodzinski

, Zeichen

. Recurrent shoulder instability among athletes: changes in quality of life, sports activity, and muscle function following open repair. Knee Surg Sports Traumatol Arthrosc. 2007; 15(3): 295-304.

41.

Sell

, Abt

, Crawford

, Lovalekar

, Nagai

, Deluzio

, et al. Warrior Model for Human Performance and Injury Prevention: Eagle Tactical Athlete Program (ETAP) - Part I. Journal of Special Operations Medicine. 2010; 10(4): 2-21.

42.

Sell

, Tsai

, Smoliga

, Myers

, Lephart

. Strength, flexibility, and balance characteristics of highly proficient golfers. J Strength Cond Res. 2007; 21(4): 1166-71.

43.

Abt

, Sell

, Laudner

, McCrory

, Loucks

, Berga

, et al. Neuromuscular and biomechanical characteristics do not vary across the menstrual cycle. Knee Surg Sports Traumatol Arthrosc. 2007; 15(7): 901-7.