Fracture shaft of humerus

Fracture of the shaft of humerus. All information taken from authentic sources.

1. Fracture Shaft of Humerus Dr. Ashiqur Rahman Resident Orthopedics Dhaka Medical college Hospital

2. Epidemiology: - 3% of all fractures; - Most can be treated non- operatively Mechanism of injury: - Spiral fracture: A fall on the hand may twist the humerus . - Oblique or transverse fracture: A fall on the elbow with the arm abducted exerts a bending force. - A direct blow to the arm causes a fracture which is either transverse or comminuted. - Fracture of the shaft in an elderly patient may be due to a metastasis .

3. Pathological anatomy: With # above the deltoid insertion, the proximal fragment is adducted by pectoralis major. With # lower down, the proximal fragment is abducted by deltoid. Injury to the radial nerve is common, though fortunately recovery is usual.

4. Clinical features: The arm is painful, bruised and swollen. It is important to test for radial nerve function before and after treatment. This is best done by assessing active extension of the metacarpophalangeal joints; active extension of the wrist can be misleading because extensor carpi radialis longus is sometimes supplied by a branch arising proximal to the injury.

5. Conservative treatment: - A ‘hanging cast’ is applied from shoulder to wrist with the elbow flexed 90 degrees. - The forearm section is suspended by a sling around the patient’s neck . - This cast may be replaced after 2–3 weeks by a short ( shoulder to elbow ) cast or a functional polypropylene brace which is worn for a further 6 weeks . - The wrist and fingers are exercised from the start.

6. - Pendulum exercises of the shoulder are begun within a week. - Active abduction is postponed until the fracture has united (about 6 weeks for spiral fractures but often twice as long for other types). - Once united, only a sling is needed until the fracture is consolidated.

7. **** Patients often find the hanging cast uncomfortable, tedious and frustrating . -they can feel the fragments moving and that is sometimes quite distressing . -The temptation is to ‘do something’, and the ‘something’ usually means an operation .

8. It is as well to remember: ( i ) That complication rate after internal fixation of humerus is high. (ii) That great majority of humeral # unite with non-operative treatment and (iii) There is no good evidence that union rate is higher with fixation(and the rate may be lower if there is distraction with nailing or periostel stripping with plating). (iv) There are nevertheless, some well-defined indications for surgery.

9. The goal of operative treatment: - Reestablish length, alignment, and rotation - Stable fixation that allows early motion and ideally - Early weight bearing on the fractured extremity. Options for fixation: 1 . Plate osteosynthesis (“gold standard”) 2 . Intramedullary nailing, and 3 . External fixation.

10. - In 1963, Holstein and Lewis associated a special type of fracture of the distal humerus , a simple displaced spiral fracture , with the distal end deviating toward the radial side, with an increased rate of radial nerve palsy . - They reported a high incidence of entrapment of the nerve within this type of fracture and recommended radial nerve exploration in the presence of clinical symptoms.

11. - Subsequent studies confirmed an increased risk of radial nerve injury with this type of fracture but supported the expectant policy even in the presence of clinical symptoms. - As their findings indicated that the radial nerve usually recovers regardless of the pattern and location of the humeral shaft fracture .

12. - Heckler and Bamberger114 surveyed practice tendencies in USA by sending a questionnaire to 2,650 physicians regarding their practice in cases of humeral shaft fracture associated with radial nerve palsy. - From 558 responses, the authors concluded that most physicians agreed that: …The incidence of recovery is high and observation is justified .

13. IF of Holstein Lewis fracture

14. Anatomy of ar m Arm is well enveloped with muscles and soft tissues. So prognosis is good. Medial and lateral intermuscular septa are tough fibrous band that divide the arm in anterior and posterior compartment. - Anterior compartment has three muscles: o Biceps brachii , o Brachialis, o Coracobrachialis - Posterior compartment: o Triceps Brachii Anterior compartment muscles BBC is supplied by musculocutaenious branch and arterial supply by branches of brachial artery.

15. Approaches: -Anterolateral approach (brachialis-splitting approach ) - A posterior approach (triceps splitting or modified posterior approach )

16. Antero-lateral approach to the shaft of the Humerus ( Thompson;Henry ) - Incise the skin in line with the anterior border of the deltoid muscle from a point midway between its origin and insertion, distally to the level of its insertion, and proceed in line with the lateral border of the biceps muscle to within 7.5 cm of the elbow joint. - Divide the superficial and deep fasciae, and ligate the cephalic vein . - In the proximal part of the wound, retract the deltoid laterally and the biceps medially to expose the shaft of the humerus .

17. - Distal to the insertion of the deltoid, expose the brachialis muscle , split it longitudinally to the bone, and retract it sub- periosteally , the lateral half to the lateral side and the medial half to the medial. -Retraction is easier when the tendon of the brachialis is relaxed by flexing the elbow to a right angle. The lateral half of the brachialis muscle protects the radial nerve as it winds around the humeral shaft.

18. Modified posterior approach(Triceps-Reflecting)

19. Complications of Shaft Humerus # Early: 1 . Vascular injury: Any injury to brachial artery 2 . Nerve injury: a . Nerve injury Radial nerve palsy (wrist drop and paralysis of the metacarpophalangeal extensors) may occur with shaft fractures . The commonest associated injury to a closed diaphyseal humeral fracture is the injury of the radial nerve ( 10% to 12% of all closed humeral shaft fractures. b . Particularly oblique fractures at the junction of the middle and distal thirds of the bone (Holstein–Lewis fracture).

20. c . If nerve function was intact before manipulation but is defective afterwards, it must be assumed that the nerve has been snagged and surgical exploration is necessary. d . Otherwise, in closed injuries the nerve is very seldom divided, so there is no hurry to operate as it will usually recover. e . The wrist and hand must be regularly moved through a full passive range of movement to preserve joint motion until the nerve recovers.

21. f . If there is no sign of recovery by 12 weeks, the nerve should be explored . g . It may just need a neurolysis , but if there is loss of continuity of normal-looking nerve then a graft is needed. h . The results are often satisfactory but, if necessary, function can be largely restored by tendon transfers Median and ulnar nerve can be injured in 1.3 % and 2.4% respectively.

22. Late: 1 . Delayed and non-union 2 . Joint stiffness