FRACTURES OF SHAFT HUMERUS

Dr. Laxmikanth.SP.G in M.S. (Ortho)Gandhi Medical College

INTRODUCTIONAccounts for 1 to 3% of all fractures

Most are treated conservatively (easiest of all long bones )

Minimal functional deficit even without anatomical reduction provided by wide range of motion provided at shoulder and elbow joints

INCIDENCE

RELAVENT ANATOMY

Extends from the upper border of the insertion of the pectoralis major proximally to the supracondylar ridge distally.

Proximally, the humerus is roughly cylindrical in cross section, tapering to a triangular shape distally.

The medullary canal of the humerus tapers to an end above the supracondylar expansion.

The humerus is well enveloped in muscle and soft tissue ( good prognosis ).Divided into ant & post compartments by medial lateral inter muscular septi. The anterior compartment contains coracobrachialis biceps brachii brachialis brachial artery median nerve. ulnar nerve passes from the anterior to the posterior compartment as it travels from proximal to distal and enters the cubital tunnel.

The posterior compartment contans triceps muscle radial nerve & profunda brachii artery run together all the course.

Radial nerve then passes to ant compartment by piercing lateral septum

MECHANISM OF INJURY

In majority of cases simple fall or twist in older people high energy trauma in young people.

Fractures in trivial trauma suspect pathological fracture (metastatic or osteoporosis )

Mismatch between mech of injury and fracture pattern suspect domestic abuse

DIAGNOSISBy clinical examination and imaging studies Clinical examination After resuscitation and stabilizing the patient injured limb should be looked for swelling deformity crepitus and abnormal mobility

Look for any external wounds and classify as per gustillo`s classification and lastly distal neurovascular deficit.

Examination of the shoulder and elbow joint is mandatory.

IMAGING STUDIES

PLAIN RADIOGRAPH -- in both A-P &lateral views including shoulder and elbow joint is sufficient for diagnosing fracture level and its pattern.

CT SCAN –fractures with intra articular extension. to know rotation mal alignment.

ANGIOGRAM – for any vascular injury

CLASSIFICATIONThere is no universally accepted system for humoral shaft fractures

They can be classified according to fracture pattern transverse oblique spiral and comminuted fracture level upper, middle, lower third soft tissue injury Gustillo`s system

Finally pathological and peri prosthetic fractures

AO /ASIF CLASSIFICATION SYSTEM

TREATMENTNon operative operative

NON OPERATIVE TREATMENTUnion rate 80 to 90%Factors favoring conservative management are well covered with muscles Rich blood supply does not bear weight, easily splinted.Mininal functional limitation after considerable malunion also favours non operative treatment.

Methods of conservative treatment are skeletal traction, abduction casting and splinting, Velpeau dressing, hanging arm cast, functional bracing. FUNCTIONAL BRACING : developed by SERMIENTO works on the principles of the hydraulic effect of the brace, active contraction of the muscles, beneficial effect of gravity.

Union rates with functional bracing are 96 to 100%. It is considered as “gold standard” for nonoperative treatment because easy application, adjustability, allowance of shoulder and elbow motion, low cost, reproducible results. Guidelines for acceptable reduction are shortening < 5 cm rotation of < 30 degrees. angulation <20 segrees

U-shaped coaptation splint

Functional bracing

OPERATIVE TREATMENT

Some other indications for operative management are chronic fracture problems like non union mal union delayed union infection

SURGICAL APPROACHES

Antero lateral /lateral approach Posterior approach Antero medial approach Modified Posterior Approach (Triceps-Reflecting)

Antero lateral approach

Preferred for middle and proximal third humeral shaft fractures that require plate fixation.

Extension : proximally coracoid process, distally ant margin of supra condylar ridge.

Courses through deltoprctoral groove and lateral border of biceps brachii.

Biceps retracted anteriorly and triceps posteriorly

Brachialis is splitted to expose humerus

Posterior approach

Antero medial approach Provides exposure to the brachial artery and median and ulnar nerves.

Begins distally at the medial epicondyle and extends proximally along the posterior edge of the biceps brachii muscle. After splitting of the superficial fascia, the ulnar nerve is identified and retracted posteromedially.

The median nerve and brachial artery are identified and retracted anterolaterally.

Advantages of this approach are the excellent exposure of the neurovascular structures medially.

The scar is cosmetically appealing. Neurovascular injury is a major complication. Proximal extension is very difficult.

Modified Posterior Approach (Triceps-Reflecting)

Intramedullary Fixation

Flexible nails rush nails (rotational instability ) enders nailsInterlocking nails (preferred)Self locking expandable nails (technically demanding)

Techniques

Anterograde technique Rretrograde technique

Anterograde technique

Disadvantages are post op shoulder pain axillary n injury radial n injury

It is avoided in cases with pre existing shoulder pathology who demands upper limb wt bearing for ambulatioRetrograde technique:Entry point – 2cm above/at superior aspect of olecrenon fossa in midline

Before closing thorough washing to be done to prevent heterotrophic calcification around elbow

Intramedullary nailing is indicated for segmental fractures for proximal–middle third junction fractures pathological fractures fractures with poor soft-tissue coverage fractures in obese patients

Intramedullary nailing is avioded in narrow diameter (<9 mm) canals .

PLATE OSTEOSYNTHESIS

Plate osteosynthesis is the “gold standard” of fixation for humeral shaft fractures.

Advantages of plating over other techniques are minimal shoulder or elbow morbidity, high union rates, low complication rates, average union rate of 96.7%. can be used for fractures with both proximal and distal extension

4.5-mm,broad DCP/limited-contact dynamic compression plate

4.5-mm, narrow DCP/limited-contact dynamic compression plate

Locking compression plates

Pre contour plates for metaphyseal extension

Implants

MIPO technique is advocated for shaft humerus fractures but associated with radial nerve injuries

Pronation of forearm brings nerve close to plate

So fixation done in forearm in supination

EXTERNAL FIXATION

Used as temporary method for fractures with contraindications to plate or nail fixation. Compound fractures Frankly infected fractures Fractures with poor soft tissues (such as burns) Rapid stabilization as in damage-control orthopaedics

It carries high complication rates like pin tract infection non union

Post operative care

If follow-up radiographs show maintenance of the reduction light weights are allowed at 6 weeks Regular weights at 12 weeks. Heavy work at 16 weeks. Sporting activities, such as tennis and golf, can also be started about 4 months after surgery.

Humerus shaft fracture with Radial Nerve Palsy

Most commonly injured with fractures of the humeral shaft because of

its spiral course at the back of humerus its relatively fixed in distal arm as it penetrates the lateral intermuscular septum. Mostly the radial nerve injury is a neurapraxia, with recovery rates of 100% in low-energy injuries and 33% in high-energy injuries

Treatment strategy is

INITIAL OBSERVATION AND LATE EXPLORATION

Recovery after nerve injury mostly spontaneous and should show signs of recovery in 3 to 4 months

ENMG and NCS should be conducted at 6 and 12 weeks

Exploration done when no recovery even after 4 to 6 months

Ultrasonography can beuseful in diagnosing entrapped or lacerated radial nerves.

By this indications for nerve exploration would be more specifically defined.

Pathologic fractureClosed inter locking nailing is preferred method Advantages are less chances of infection wound complications after radiation blood loss

Open reduction is preferred only when tissue biopsy to be taken, and fixed with bone cement, auto/ allograft.

Metaphyseal fractures best treated with excision and prosthetic replacement.

COMPLICATIONS

Non union

Implant failure

Infection

Radial nerve injury

Implant failureDue to selecting wrong implant wrong technique infection poor bone quality

InfectionIf infection sets culture to be taken i.v antibiotics to be started

If the fixation rigid enough left in place

If not remove it ,debride and ex fix to be applied

After controlled, reoperation

Role of illizarov is limited

Thank you