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The pelvic support osteotomy: indications and preoperative planning.

Pafilas D, Nayagam S - Strategies Trauma Limb Reconstr (2008)

Bottom Line: The pelvic support osteotomy is a double level femoral osteotomy with the objective of eliminating a Trendelenburg and short limb gait in young patients with severe hip joint destruction as a consequence of neonatal septic arthritis.We present an analysis of the preoperative assessment that will assist the surgeon to plan out the procedure.(b) Where should the second osteotomy be performed and what is the magnitude of varus and derotation desired at this level?

View Article: PubMed Central - PubMed

Affiliation: Royal Liverpool University and Royal Liverpool Children's Hospitals NHS Trusts, Eaton Road, Liverpool, L12 2AP, UK.

ABSTRACT
The pelvic support osteotomy is a double level femoral osteotomy with the objective of eliminating a Trendelenburg and short limb gait in young patients with severe hip joint destruction as a consequence of neonatal septic arthritis. The osteotomy has seen several changes and a brief historical overview is provided to set the evolution of the modifications of the procedure in context. We present an analysis of the preoperative assessment that will assist the surgeon to plan out the procedure. Specifically, we set out to answer the following questions: (a) Where should the first osteotomy be performed and what is the magnitude of valgus and extension correction desired at this level? (b) Where should the second osteotomy be performed and what is the magnitude of varus and derotation desired at this level?

No MeSH data available.


Related in: MedlinePlus

Performing a valgus osteotomy equal in size to the maximum range of adduction plus any adduction contracture will bring the femoral shaft to its normal inclination of 9° to the vertical. Bringing the shaft to vertical therefore overcorrects by 9° (valgus correction a). This does not lateralise the shaft or knee joint sufficiently. Therefore an overcorrection in the region of 30° is preferable to allow a shift of the limb from the midline (valgus correction b). This overcorrection in effect produces an ‘abduction contracture’, i.e. in order to stand with both legs parallel, the patient has to tilt the pelvis
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Fig5: Performing a valgus osteotomy equal in size to the maximum range of adduction plus any adduction contracture will bring the femoral shaft to its normal inclination of 9° to the vertical. Bringing the shaft to vertical therefore overcorrects by 9° (valgus correction a). This does not lateralise the shaft or knee joint sufficiently. Therefore an overcorrection in the region of 30° is preferable to allow a shift of the limb from the midline (valgus correction b). This overcorrection in effect produces an ‘abduction contracture’, i.e. in order to stand with both legs parallel, the patient has to tilt the pelvis

Mentions: Slightly different recommendations have been made with regard to the amount of abduction performed at this osteotomy. Most authors have suggested an abduction angle that is either equal to the single stance pelvic drop angle or the measured range of adduction, plus an overcorrection factor of 15°–25°. We draw attention to two practical points in this regard: firstly it can be difficult to obtain a single stance pelvic drop angle without the patient requiring some form of additional support to achieve balance and, secondly, the measured range of adduction does not account for an adduction contracture that may commonly exist. We therefore recommend the angle of valgus correction to be estimated as the sum of the measured range of adduction plus the size of adduction contracture, if present. To this is added an amount of overcorrection. It is often quoted that an overcorrection offsets the loss of the valgus from remodelling at the osteotomy site. We would also like to point out that, irrespective of the size of overcorrection, much of this is cancelled if the second distal femoral osteotomy restores the position of knee joint inclination to parallel to the horizontal line of the pelvis. This can be explained as follows: any overcorrection at the proximal level leaves the patient with an ‘abduction contracture’, i.e. an inability to bring the leg parallel to the other in bipedal stance unless there is tilting of the pelvis (Fig. 5). If a varus correction is produced at the distal osteotomy, then the effect of this ‘abduction contracture’ is lost (and so will any overcorrection at the proximal osteotomy). Therefore maintaining a residual ‘abduction contracture’, which is what an overcorrection becomes, is a function of incomplete correction of the axis at the distal osteotomy. However we believe that an overcorrection factor should be added to the valgus correction at the proximal osteotomy because a failure to do so will leave the entire limb medialised and much closer to the midline than the contralateral side. In fact, an overcorrection of 9° will leave the shaft of the femur parallel to the vertical axis of the pelvis (Fig. 5). In view of this, we suggest that the overcorrection performed at the proximal osteotomy level should be greater than the 25° suggested by Choi et al. [9] to enable an abduction of the shaft of the femur away from the midline. An overcorrection of 30°–40° brings the post-osteotomy angle of Milch close to the recommended 240°.Fig. 5


The pelvic support osteotomy: indications and preoperative planning.

Pafilas D, Nayagam S - Strategies Trauma Limb Reconstr (2008)

Performing a valgus osteotomy equal in size to the maximum range of adduction plus any adduction contracture will bring the femoral shaft to its normal inclination of 9° to the vertical. Bringing the shaft to vertical therefore overcorrects by 9° (valgus correction a). This does not lateralise the shaft or knee joint sufficiently. Therefore an overcorrection in the region of 30° is preferable to allow a shift of the limb from the midline (valgus correction b). This overcorrection in effect produces an ‘abduction contracture’, i.e. in order to stand with both legs parallel, the patient has to tilt the pelvis
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2553427&req=5

Fig5: Performing a valgus osteotomy equal in size to the maximum range of adduction plus any adduction contracture will bring the femoral shaft to its normal inclination of 9° to the vertical. Bringing the shaft to vertical therefore overcorrects by 9° (valgus correction a). This does not lateralise the shaft or knee joint sufficiently. Therefore an overcorrection in the region of 30° is preferable to allow a shift of the limb from the midline (valgus correction b). This overcorrection in effect produces an ‘abduction contracture’, i.e. in order to stand with both legs parallel, the patient has to tilt the pelvis
Mentions: Slightly different recommendations have been made with regard to the amount of abduction performed at this osteotomy. Most authors have suggested an abduction angle that is either equal to the single stance pelvic drop angle or the measured range of adduction, plus an overcorrection factor of 15°–25°. We draw attention to two practical points in this regard: firstly it can be difficult to obtain a single stance pelvic drop angle without the patient requiring some form of additional support to achieve balance and, secondly, the measured range of adduction does not account for an adduction contracture that may commonly exist. We therefore recommend the angle of valgus correction to be estimated as the sum of the measured range of adduction plus the size of adduction contracture, if present. To this is added an amount of overcorrection. It is often quoted that an overcorrection offsets the loss of the valgus from remodelling at the osteotomy site. We would also like to point out that, irrespective of the size of overcorrection, much of this is cancelled if the second distal femoral osteotomy restores the position of knee joint inclination to parallel to the horizontal line of the pelvis. This can be explained as follows: any overcorrection at the proximal level leaves the patient with an ‘abduction contracture’, i.e. an inability to bring the leg parallel to the other in bipedal stance unless there is tilting of the pelvis (Fig. 5). If a varus correction is produced at the distal osteotomy, then the effect of this ‘abduction contracture’ is lost (and so will any overcorrection at the proximal osteotomy). Therefore maintaining a residual ‘abduction contracture’, which is what an overcorrection becomes, is a function of incomplete correction of the axis at the distal osteotomy. However we believe that an overcorrection factor should be added to the valgus correction at the proximal osteotomy because a failure to do so will leave the entire limb medialised and much closer to the midline than the contralateral side. In fact, an overcorrection of 9° will leave the shaft of the femur parallel to the vertical axis of the pelvis (Fig. 5). In view of this, we suggest that the overcorrection performed at the proximal osteotomy level should be greater than the 25° suggested by Choi et al. [9] to enable an abduction of the shaft of the femur away from the midline. An overcorrection of 30°–40° brings the post-osteotomy angle of Milch close to the recommended 240°.Fig. 5

Bottom Line: The pelvic support osteotomy is a double level femoral osteotomy with the objective of eliminating a Trendelenburg and short limb gait in young patients with severe hip joint destruction as a consequence of neonatal septic arthritis.We present an analysis of the preoperative assessment that will assist the surgeon to plan out the procedure.(b) Where should the second osteotomy be performed and what is the magnitude of varus and derotation desired at this level?

View Article: PubMed Central - PubMed

Affiliation: Royal Liverpool University and Royal Liverpool Children's Hospitals NHS Trusts, Eaton Road, Liverpool, L12 2AP, UK.

ABSTRACT
The pelvic support osteotomy is a double level femoral osteotomy with the objective of eliminating a Trendelenburg and short limb gait in young patients with severe hip joint destruction as a consequence of neonatal septic arthritis. The osteotomy has seen several changes and a brief historical overview is provided to set the evolution of the modifications of the procedure in context. We present an analysis of the preoperative assessment that will assist the surgeon to plan out the procedure. Specifically, we set out to answer the following questions: (a) Where should the first osteotomy be performed and what is the magnitude of valgus and extension correction desired at this level? (b) Where should the second osteotomy be performed and what is the magnitude of varus and derotation desired at this level?

No MeSH data available.


Related in: MedlinePlus