CHAPTER 49 • ELBOW INSTABILITY 291- Reactive neuromuscular control:
a. Reflexive muscular stabilization induced by
sudden alterations in joint position.
b. Eccentric activities useful. - Functional motor patterns:
a. Progression to the actual throwing activity.
b. Analyze direction of force, amount of load-
ing, and resultant muscle action to incorpo-
rate functional progression.
REFERENCES
Bennett GE: Elbow and shoulder lesions of baseball players. Am
J Surg 98:484–492, 1959.
D’Alessandro DF, Bradley JP, Fleischli JF, et al: Prospective
evaluation of electrothermal arthroscopic capsulorrhaphy
(ETAC) for shoulder instability: Indications, technique and
preliminary results. Annual Closed Meeting of American
Shoulder and Elbow Surgeon, New York, NY, 1998.
Glousman R, Jobe FW, Tibone, et al: Dynamic electromyo-
graphic analysis of the throwing shoulder with glenohumeral
instability. J Bone Joint Surg 70:220–226, 1988.
Gowan ID, Jobe FW, Tibone JE, Moynes DR: A comparative
electromyographic analysis of the shoulder during pitching.
Professional versus amateur pitchers. Am J Sports Med
15:586–590, 1987.
Halbrecht JL, Tirman P, Atkin D: Internal impingement of the
shoulder: Comparison of findings between throwing and non-
throwing shoulders of college baseball players. Arthroscopy
15:253–258, 1999.
Jobe CM, Sidles J: Evidence for a superior glenoid impingement
upon the rotator cuff: Anatomic, kinesiologic, MRI and arthro-
scopic findings (Abstract). 5th International Conference on
Surgery of the Shoulder. Paris, France, July 1992.
Kibler WB: The role of the scapula in athletic shoulder function.
Am J Sports Med26:325–337, 1998.
Kvitne RS, Jobe FW: The diagnosis and treatment of anterior
instability in the throwing athlete. Clin Orthop291:107–123,
1993.
Lephart SM, Henry TJ: Restoration of proprioception and neuro-
muscular control of the unstable shoulder, in Lephart SM and
Fu FH (eds.): Proprioception and Neuromuscular Control in
Joint Stability. New York, NY, Human Kinetics, 2000,
pp 405–413.
Lephart SM, Kocher MS, Fu FH, et al: The physiological basis
for open and closed kinetic chain rehabilitation for the upper
extremity. J Sport Rehab 5:71–87, 1996.
Levitz CL, Andrews JR, Dugas J: The use of thermal capsular
shrinkage in the management of labral detachments in elite
throwing athletes. Annual Meeting American Academy of
Orthopaedic Surgeons. Orlando, FL, 2000.
Lombardo SJ, Kerlan RK, Jobe FW, et al: Posterior shoulder
lesions in throwing athletes. Am J Sports Med 5:106–110,
1977.
Meister K, Andrew JR, Batts J, et al: Symptomatic thrower’s
exostosis. Arthroscopic evaluation and treatment. Am J Sports
Med 27:133–136, 1999.
Morgan CD, Burkhart SS, Palmeri M, et al: Type II SLAP
lesions: Three subtypes and their relationships to superior
instability and rotator cuff tears. Arthroscopy14:553–565,
1998.
Rodosky MW, Harner CD, Fu FH: The role of the long head of
the biceps muscle and superior glenoid labrum in anterior
stability of the shoulder. Am J Sports Med 22:121–130,
1994.
Rubenstein DL, Jobe FW, Glousman RE, et al: Anterior capsulo-
labral reconstruction of the shoulder in athletes. J Shoulder
Elbow Surg 1:229–237, 1992.
Snyder SJ, Karzel RP, Delpizzo W, et al: SLAP lesions of the
shoulder. Arthroscopy6:274–279, 1990.
Tibone JE, Jobe FW, Kerlan RK, et al: Shoulder impingement
syndrome in athletes treated by anterior acromioplasty. Clin
Orthop198:134–140, 1985.
Walch G, Boileau P, Noel E, et al: Impingement of the deep sur-
face of the supraspinatus tendon on the posterior glenoid rim:
An arthroscopic study. J Shoulder Elbow Surg 1:238–245,
1992.49 ELBOW INSTABILITY
Derek H Ochiai, MD
Robert P Nirschl, MD, MSINTRODUCTION- The elbow is a highly congruent, complex hinge joint.
•Although constrained by bony architecture and the
stabilizing ligaments, it accounts for 20% of all dislo-
cations (Josefsson, Johnell, and Gentz, 1984). - Most instabilites result from either a single trauma
(straight posterior or posterolateral rotatory instability,
[PLRI]) or chronic overuse in the overhead athlete
(valgus instability). A congenitally shallow ulno-
humeral joint may contribute to single trauma insta-
bilities.
FUNCTIONAL ANATOMY- The elbow joint comprises the humeroradial, humer-
oulnar, and proximal radioulnar joints. - The lateral portion of the distal humerus, the capit-
ulum, articulates with the radial head. The medial
portion of the humerus, the trochlea, articulates with
the trochlear notch of the ulna. The radial notch of