3 Common elbow abnormalities 1- Changes in Carrying Anglethe normal value of carrying angle is10-5 degrees valguma) Cubitum Varum: abnormal decrease in carrying angle.b) Cubitum Valgum: abnormalincrease in the angle.
4 2- Changes in bony alignment following fractures: Fracture of distal humerus or proximal ulna can alter the normal orientation of the articular surfaces of humeroulnar articulation.
5 a)From frontal view:Any change in the relative alignment olecranon between the two humeral epicondyles affects both flexion and extension ranges
6 ii. a hypothetical increase in the superior orientation of the trochlear notch increases extension ROM and decreases flexion ROM.2- Cubitum Recurvatum:hyperextension of elbow joint.
7 3-Humeroulnar Disolcation Posterior dislocation:As there is little bony limitation to the trochlear notch being pushed off trochlea.b) Posterolateral dislocation:More frequent, occur in a combination of lateral and posterior movement of the forearm resulting from a force directed laterally on the distal forearm.
8 4- Superior radioulnar dislocation “pulled elbow injuries” Occur at preschool children due to weakness of the annular ligament that allow the radial head to slip away from its ring by the tensile force applied to fore arm
9 5-Joint swelling and elbow flexion Position of comfort in case of swelling is significant elbow flexi which is due to minimized tension on joint capsule at 80 degree flexion thus reducing stress on ligaments and minimize pain. But if condition persists this leads to flexion contractures.
10 6-BursitisSuperficial location makes it extremely susceptible to injury (acute or chronic) --direct blow
11 7-Musculature/Tendinitis a) Medial Epicondylitis – chronic “Pitcher’s, Golfer Elbow” :Caused by repeated flexion (common flexor tendon), valgus stresses, faulty biomechanicsb) Lateral Epicondylitis – chronic “Tennis Elbow”Caused by -overuse of extensor /supinator muscles, faulty biomechanics (common extensor tendon).-faulty backhand, too much topspin, too small or large grip.
12 9- pathomechanics of Muscles around elbow Biceps BrachiiBrachioradialisPronator TeresBrachialisa) Flexor groups:
13 i. Biceps brachii Effect of weakness: Loss of flexion and radioulnar supination strength that is compensated by other muscles.Also may cause slight weakness in shoulder flexionSupinated pronated
14 Effect of tightness:Limited extension range in elbow and shoulder with tightness degree changes by alteration in other joint positionsif Shoulder in extension position lead to limit extension range at elbow and vice versaForearm pronation lead to limit extension range at elbow and vice vera
15 ii. BrachiallisBrachialisEffect of weakness: Decreased elbow flexion in all forearm ranges.Effect of tightness: Limited extension range regardless of shoulder and forearm position.n.b. differentiate between brachialis tightness and anterior capsular tightnessTight muscular tissue feel rubbery or springy at end range. Capsular tightness end feel is harder and less spring
16 iii. brachioradialis Effect of weakness: Effect of tightness: Decreased elbow flexion strength in addition to decreased resisted pronation and supination as forearm moves toward neutral positionEffect of tightness:Limited extension range in elbow and supination and pronation rangeDuring rapid elbow flexion it acts as stabilizing to elbow joint against radial aaceleration
17 iv. Supinator Effect of weakness: Decreased forearm forceful supination strength in case of intact biceps.No supination with elbow extended.Effect of tightness:A two joint muscle thus max tightness appear when performing elbow extension and pronation
19 i. Pronator teris Effect of weakness: Effect of tightness: Pronator TeresEffect of weakness:Decreased elbow flexion andforearm pronation strengthIn loading situations asloosening a screwEffect of tightness:Limited extension range in elbow and supination. A two joint muscle thus max tightness appear when performing elbow extension and supination
20 ii.Triceps brachii Effect of weakness: Effect of tightness: A profound decrease in elbow extension.In tetraplegia with zero triceps push up could be done with elbow mechanically locked in hyperextension.Effect of tightness:Limited flexion range in elbow and may contribute to diminished shoulder elevation ROM that could interferes with functional daily activities as most daily activities can be performed with a total elbow flexion excursion of about 100°. Ex personal care activities as feeding and hygeine.
21 Other j positionsEffect of tightness (range)Effect of weakness (strength)Muscle-Shoulder radioulnarElbow ext. rangepron. RangeElbow flex. strengthflex. strength at shoulderSup. strengthBiceps brachiiNonelbow extelbow flex. strength in all forearm positionsbrachialiselbow flex strengthresisted pron. and sup. force output as forearm moves toward neutral positionbrachioradialispronforceful sup and pron with extended elbowsupinatorRadioulnarsupresisted elbow flexresisted in pronPronator tereselbow flexelbow flexion strngthTriceps brachii