Incidence of varus deformity in subtrochanteric fractures

managed using the standard SIGN nail

Brian Paketh Akimu C. Mageza

Valentine Mandizvidza Maxman F. Gova George A.N. Vera

Introduction • Lesser trochanter to 5cm distal

• 10 - 34% of all hip fractures

• Two population groups:

• Older - osteoporotic

• Younger - high energy trauma

• (Fielding. Clinic Orthopod 192; 86, 1973. Heipe JBJS 61A;730.1979)

Pathoanatomy

• Deforming forces on the proximal fragment:

• Abduction - gluteus medius & gluteus minimus

• Flexion - iliopsoas

• External rotation - short external rotators

• Deforming forces on the distal fragment:

• Adduction & shortening - adductors

Neck Shaft Angle

Biomechanical considerations

Compressive stress in the medial cortex larger than

Tensile stress in the lateral cortex

Schatzker et al.1980

AO classification

Our beautiful question...

What is the incidence of varus deformity in subtrochanteric fractures managed using the standard sign nail at

Parirenyatwa hospital?

Materials & Methods

• Clinical data of 27 consecutive patients

• March 2013 to October 2014

• Inclusion criteria:

• Subtrochanteric fractures managed at Parirenyatwa Group of Hospitals, Harare, Zimbabwe using the standard sign nail

Materials & Methods...

• Imaging was assessed pre - and post - operatively

• Post operative radiography times were:

• Immediately post op

• 6weeks

• 12weeks

• 24weeks

Materials & Methods

• Parameters looked at were:

• Neck Shaft angle

• Callus formation

• Implant failure

• Limb length discrepancy

• Rotational deformity

Methodology

• Standard sign nail used in all cases

• Antegrade approach

• Open reduction done

• Fluoroscopy not used

Calculating the Neck Shaft Angle

Results

• Sex distribution

• 23male, 4 female

0

6

12

18

24

30

male female

Results

• Age distribution

• 16 - 84. Mean 42yrs

0

2.25

4.5

6.75

9

11.25

0-9 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89

Results

• One patient: bilateral subtrochanteric fractures

• One patient: pathological fracture

• 2 died in post operative period

Results... • 8 (29%) had varus deformity, 5 - 15degrees

• 4 (14%) had evidence of implant failure

57% 29%

14%

Case 1 • JK, 25yrs, MVA

Case 2

GF

42/m

Mine shaft injury

Case 3

• SM

• 34/M

• MVA

Conclusion • The standard sign nail may be used as a fixation method of

subtrochanteric fractures in a resource limited setting

• Reasons from this case series:

• 28% varus deformity

• 14% implant failure

• Fluoroscopy not required

• Implant easily accessible

Conclusion...

• Ramchandra P.T; Comperative study between Dynamic Hip Screw and Proximal Femoral Nail in the management of trochanteric and subtrochanteric femoral fractures.

Number of patients managed with the PFN

Number of patients managed with the DHS

Varus deformity 5% 10%

References 1. Loizou C.L, McNamara K, Ahmed G.A; Classification of subtrochanteric femoral fractures: Injury, Vol41, Issue

7, 2010, 922-928.

2. Velasco R.U, Comfort T.H; Analysis of treatment problems in subtrochanteric fractures of the femur: J Trauma, Vol 18, Issue 7, 78, 513-523

3. Starr A.J, Hay M.T, Reinert C.M; Cephalomedullary nails in the treatment of high energy proximal femur fractures in young patients: a prospective, randomized comparison of trochanteric versus piriformis fossa entry portal: J Orthop Trauma, Vol 20, Issue 4, 2006, 240-246

4. Brien W.W, Wiss D,A, Becker Jr; Subtrochanteric femur fractures: a comparison of the Zickel nail, 95degrees blade plate, and interlocking nail. J Orthop Trauma, Vol 5, Issue 4, 91, 458-464

5. Shuka S, Johnston P, Ahmad M.A, Wynn-Jones H; Outcome of traumatic subtrochanteric femoral fractures fixed using Cephalomedullary nails: Injury, Vol 38, Issue 11, 2007, 1286-1293

6. Bergman G.D, Winquist R.A, Mayo K.A; Subtrochanteric fractures of the femur. Fixation using the Zickel nail. J Bone Joint Surg(Am). Vol 69-A, 87, 1032-1040

7. Vaidya S.V, Dholakia D.B, Chatterjee A; The use of a dynamic condylar screw and biological reduction techniques for subtrochanteric femur fractures. Injury, Vol 34, Issue 2, 2003, 123-128

Thank you

Siyabonga

Tatenda