Tuesday, November 25, 2014

Pediatric radial neck fractures

The following case is a 11 y/o patient who presented with elbow pain after a fall. He presented with a radial head fracture that was angulated  45 degrees and had loss of forearm rotation. Due to the forearm rotation loss and degree of angulation operative fixation of the fracture was chosen. Injury films are shown below and xrays at one month after surgery.

Displacement and 45 deg of angulation on AP view

45 degrees of angulation at the radial neck (posterior)

2 weeks postop

One month postop


At 4 months post op there is significant remodeling and the patient lacks only 10 degrees of full pronation. Supination is full.





These injuries can be associated with:
MCL injury
Elbow dislocation
DRUJ dislocation
Capitellum fracture
Fracture of the olecranon or shaft of the ulna

Closed reduction should be attempted in the OR and if the reduction is not satisfactory then pinning of the fracture should be performed. If forearm rotation is less than 60 degrees then reduction is usually unsatisfactory

Accetable Reduction: 
    - age < 10 yrs: 
          - < 10 deg usually remodels with growth 
          - up to 30 deg of residual angulation can be accepted; 
          - angulation is > 30 deg 
                - closed manipulative reduction or percutaneous pinning to manipulate frx; 
    - age > than 10 yrs: 
          -if angulation > 30 deg, or translocation > 3 mm then poor results can be expected; 
          - inability to reduce angulation < 45 deg, requires ORIF 
          - inability to pronate and supinate the forearm more than 60 deg, is another sign that that the reduction is not adequate; 


It is important to educate patients and family that after this injury there is a change of loss of forearm rotation.

Possible complications are:

(1) Malunion may cause shortening of the radius and increased cubitus valgus, depending on pt's age & degree of cartilagenous damage.

(2) Non union 
This happens when there is severe fracture displacement at the time of injury or poor fixation technique. Nonunion can be treated with observation, radial head and neck excision (which should be avoided) . ORIF with bone graft has also been described. Healing of the nonunion is not always associated to improvement of clinical symptoms; 
                  
(3) Avascular necrosis

These complications are seen more often if extensive soft tissue damage is performed at the time of surgery or trauma that may cause premature fusion of upper radial epiphysis that occurs frequently after displaced fractures



Wednesday, November 19, 2014

Corrective osteotomy for surgical neck proximal humerus varus malunion

The following case is a patient in her 40s who presented with a non displaced fracture of the proximal humerus. Serial radiographs at 2 and 4 weeks demonstrated varus collapse and malunion of the proximal humerus. Corrective osteotomy was performed in the operating room and application of a proximal humerus locking plate. We prefer to use the minimum length of humeral head screws necessary for fixation to avoid penetration of the articular surface, AVN and post-traumatic arthritis.

We elected to correct the deformity due to the young age and high level of activity of the patient. Two-part fractures of the surgical neck may heal in varus and anterior angulation. The humeral shaft displaces anteromedially because of the pull of the pectoralis major, and the proximal fragment is abducted by the rotator cuff. If the deformity is great enough, loss of forward flexion and abduction may be significant. 


Fracture well aligned at presentation

Two weeks after sling immobilization there is "acceptable" varus malalignment

Grashey view of the shoulder at 4 weeks after injury. There is severe angulation (45 degrees or more) of the humeral head with partial union

Proximal humerus osteotomy and fixation using a 3.5mm locking plate
Intra-operative AP view
Intra-operative axillary view


Currently, there is no universally accepted classification of proximal humeral malunions. Generally rotational malalignment of the articular segment by more than 45 degrees in the coronal, sagittal, or axial plane is considered severe deformity by most orthopaedic surgeons.

In this case, after the osteotomy the reduction was maintained after pinning the humeral head with a heavy Steinman pin from the lateral to medial direction and rotating the fragment with the aid of the heavy pin to correct the varus deformity as shown in the picture below.
From AO Foundation

There is little in the literature regarding the treatment of varus malunions of two-part surgical neck fractures of the proximal humerus. In varus deformities, the subacromial space is decreased as the greater tuberosity becomes closer to the coracoacromial arch. The lever arm of the supraspinatus tendon and the sliding surface of the humeral head and the glenoid are likewise decreased. These anatomical changes can cause impairment of active forward flexion and abduction and pain from impingement. Such functional limitations may be unacceptable to young patients or active older patients. Some investigators recommend release of soft tissue contractures and removal of bony prominences for less severe deformities. 

Wednesday, November 5, 2014

Surgical exposure of the glenoid for total shoulder replacement

Many general orthopaedic surgeons avoid placement of a glenoid component during shoulder replacement surgery or have problems with glenoid exposure. The following pictures demonstrate the way we perform the exposure using Darrach retractors, 3 or 4 Homan retractors and 2 Gelbi retractors. The key to glenoid exposure is the release of the inferior capsule at the neck of the humerus. This is performed by external rotation of the proximal humerus as the subscapularis is sequentially released at the inferior aspect. This movement moves the axillary nerve away from the surgical field. By releasing the inferior capsule the humeral head can be displaced posteriorly for glenoid exposure.

It is important NOT to do an aggressive humeral cut to facilitate glenoid exposure because the loss of proximal humeral bone cannot be corrected and will lead to shoulder instability.

It is important to recognize that depending on the size of the patient, musculature and stiffness exposure can be challenging even if the necessary steps were taken for adequate soft tissue release. In that case although most shoulder surgeons do not admit it, bone resection from the lesser tuberosity while the humerus is dislocated posteriorly is necessary. This humeral bone resection should be just enough for drilling and reaming the glenoid and again the bone preservation should be kept in mind.

In addition, if the surgery is done on older patients (usually in their 70s or 80s) with osteopenic bone or rheumatoid disease then it might be necessary to keep the trial humeral component in the humeral canal to avoid humeral fracture during the retraction for exposure of the glenoid.

Of note, the release of the rotator cuff interval from a lateral to medial direction to the coracoid and conjoined tendon but not pass the coracoid/conjoined tendon can help with visualization at the anterior superior aspect of the glenoid.

The following pictures demonstrate the exposure and final implantation of an all poly-ethylene  glenoid component and press fit humeral stem.

Exposure of humeral head

Exposure of the glenoid


Drilling the hole for the central peg



Drilled peripheral peg holes
Implanted glenoid component





Insertion of 6 humeral Fiberwire sutures to the lesser tuberosity for repair of the subscapularis



Insertion of press fit humeral component and head




Postoperative Grashey view (sling metal adjustor superimposed - xray taken in the postanesthesia care unit)






Tuesday, November 4, 2014

Shoulder replacement for rheumatoid arthritis. Total shoulder or hemi-arthroplasty?

The following case is a female in her mid 30s who presented in the office one year ago with shoulder pain and erosive bone on bone arthritis without deformity to the glenoid. The patient was treated for a year with oral corticosteroids and infusions of anti TNF medications. She experienced minimal relief of her symptoms from rheumatological treatment and one year later she came back complaining of severe shoulder pain with intact rotator cuff muscle strength and active forward elevation of the shoulder to 45 deg due to shoulder pain.

Xrays one year apart prior to surgery are shown below and demonstrate erosion of the glenoid within the timeframe of 12 months.

12 months before surgery AP view

12 months before surgery Grashey view

Prior to surgery (5 days preop). AP view shows progression of the RA disease with further erosive changes to the central part of the glenoid

Axillary prior to surgery




We elected to proceed with a total shoulder replacement instead of a hemi-arthroplasty with the following advantages/disadvantages:

Advantages:
(1) avoidance of medial erosion of the glenoid as seen in RA patients treated with hemi-arthroplasty
(2) better pain relief compared to hemi-arthroplasty
(3) better motion compared to to hemi-arthroplasty

Disadvantages:
(1) 0.8% annualized rate of glenoid component revision. Survivorship of 80-90% at 10 years
(2) 1.2% annualized rate of symptomatic glenoid component loosening.
(3) 7.3% annualized rate of asymptomatic radiolucent lines.

For patients with DJD of the shoulder some studies report up to 50% chance of radiolucent lines at 5 years postoperatively but the need for revision is not common for polyethelyne glenoid components.

In addition, we elected pegged over keeled all polyethylene glenoid component due to better survivorship

For further information:
Failure of the glenoid component in anatomic total shoulder arthroplasty: a systematic review of the English-language literature between 2006 and 2012. Papadonikolakis A, Neradilek MB, Matsen FA 3rd. J Bone Joint Surg Am. 2013 Dec 18;95(24):2205-12.

Shoulder arthroplasty for rheumatoid arthritis: 303 consecutive cases with minimum 5-year follow-up. Barlow JD, Yuan BJ, Schleck CD, Harmsen WS, Cofield RH, Sperling JW. J Shoulder Elbow Surg. 2014 Jun;23(6):791-9.

An all poly -ethylene glenoid (cemented) component over metal backed glenoid (uncemented) was selected due to significantly higher rate of metal backed glenoid component failure and need for glenoid revision compared to the all poly-ethylene design (see Metal-Backed Glenoid Components Have a Higher Rate of Failure and Fail by Different Modes in Comparison with All-Polyethylene Components: A Systematic Review. Papadonikolakis A, Matsen FA 3rd. J Bone Joint Surg Am. 2014 Jun 18;96(12):1041-1047.)

Postoperative pictures are shown below:

Immediate postoperative Grashey view with minimal cementation of the humeral component
Axillary postoperative XR shows no dislocation or subluxation and the appropriate position and size of the humeral head

Cementation of the humeral component was necessary due to the poor bone quality because of osteopenia from long term use of oral corticosteroids.

Xrays at 6 weeks shown below