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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

Both Lorenz and Schanz osteotomies provide ‘pelvic support’. Milch described a post-osteotomy angle (β) which predicted abutment against the lateral wall of the pelvis when it exceeded the angle of pelvic inclination (α). When the difference was excessive, restriction of movement was significant and created a secondary disability
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Fig1: Both Lorenz and Schanz osteotomies provide ‘pelvic support’. Milch described a post-osteotomy angle (β) which predicted abutment against the lateral wall of the pelvis when it exceeded the angle of pelvic inclination (α). When the difference was excessive, restriction of movement was significant and created a secondary disability

Mentions: The term ‘pelvic support’ is attributed to Lance who, in 1936, used it in reference to subtrochanteric osteotomies for the treatment of congenital dislocation of the hip [1]. Variations of the procedure had been described, several pre-dating 1936, in which a medial displacement of the anatomical axis of the femur in relation to the mechanical axis produced increased stability [2]. Milch contrasted the ideologies behind the variations; some believed the angulation from the valgus osteotomy and consequent alteration of anatomical axis in relation to mechanical produced the desired effect of stability, in comparison to the view that abutment of the upper end of the osteotomised shaft of femur against the pelvis was responsible. The techniques by Lorenz [3], Schanz [4] and Ilizarov [5] deserve special mention. The subtrochanteric osteotomy designed by Lorenz was a valgus osteotomy coupled to a medial and proximal displacement of the shaft of femur (Fig. 1). The almost vertical disposition of the femoral shaft ‘supported’ the pelvis from abutment. However, the prominence of the displaced femoral shaft was noted by several authors to produce limitation of movement owing to the very same impingement against the lateral wall of the pelvis. This improved when the prominence remodelled with time or was surgically removed—interestingly, when the abutment was reduced pelvic stability was not lost in all cases. In contrast, the Schanz osteotomy (Fig. 1) was performed by introducing a valgus, and sometimes extension, position to the distal femoral segment but without the proximal displacement of the Lorenz procedure. Whilst this increased pelvic stability, it shared the same effect of abutment from the apex of angulation against the lateral wall of the pelvis, especially when the patient attempted to bring the widely abducted leg parallel to the opposite side. Both techniques therefore induced a limitation of movement from abutment. Milch highlighted this conundrum by introducing the concept of a post-osteotomy angle (angle β in Fig. 1, which is distinct from the angle of abduction at the level of the osteotomy) and its relation to pelvic inclination (angle α in Fig. 1) at the lateral wall of the ischium (Fig. 1). When this angle, whether from Schanz or Lorenz type osteotomies, exceeded pelvic inclination, impingement occurred when the patient attempted to bring the leg into parallel with the contralateral side [2]. The loss of parallelism was in effect an ‘abduction contracture’ and meant some patients, when standing, had to compensate with eversion of the foot and with tilting of the pelvis (consequently producing a relative adduction of the contralateral hip). Whilst this had the desired effect of eliminating the Trendelenburg gait (in which the pelvis tilts in the opposite direction), some surgeons erroneously increased the abduction angle (and consequently the post-osteotomy angulation) to such an excessive degree that it became a disability. Worse still, when the procedure was performed for bilateral cases this made compensation by pelvic tilting impossible [2]. Milch recommended this post-osteotomy angle should lie between 210° and 240°. In so doing, it made the procedure technically demanding as an excessive abduction angle (and correspondingly large post-osteotomy angle) produced stability at the expense of comfortable parallelism of both legs with a level pelvis, whereas one that was insufficiently abducted preserved movement but lost stability.Fig. 1


The pelvic support osteotomy: indications and preoperative planning.

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

Both Lorenz and Schanz osteotomies provide ‘pelvic support’. Milch described a post-osteotomy angle (β) which predicted abutment against the lateral wall of the pelvis when it exceeded the angle of pelvic inclination (α). When the difference was excessive, restriction of movement was significant and created a secondary disability
© Copyright Policy
Related In: Results  -  Collection

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

Fig1: Both Lorenz and Schanz osteotomies provide ‘pelvic support’. Milch described a post-osteotomy angle (β) which predicted abutment against the lateral wall of the pelvis when it exceeded the angle of pelvic inclination (α). When the difference was excessive, restriction of movement was significant and created a secondary disability
Mentions: The term ‘pelvic support’ is attributed to Lance who, in 1936, used it in reference to subtrochanteric osteotomies for the treatment of congenital dislocation of the hip [1]. Variations of the procedure had been described, several pre-dating 1936, in which a medial displacement of the anatomical axis of the femur in relation to the mechanical axis produced increased stability [2]. Milch contrasted the ideologies behind the variations; some believed the angulation from the valgus osteotomy and consequent alteration of anatomical axis in relation to mechanical produced the desired effect of stability, in comparison to the view that abutment of the upper end of the osteotomised shaft of femur against the pelvis was responsible. The techniques by Lorenz [3], Schanz [4] and Ilizarov [5] deserve special mention. The subtrochanteric osteotomy designed by Lorenz was a valgus osteotomy coupled to a medial and proximal displacement of the shaft of femur (Fig. 1). The almost vertical disposition of the femoral shaft ‘supported’ the pelvis from abutment. However, the prominence of the displaced femoral shaft was noted by several authors to produce limitation of movement owing to the very same impingement against the lateral wall of the pelvis. This improved when the prominence remodelled with time or was surgically removed—interestingly, when the abutment was reduced pelvic stability was not lost in all cases. In contrast, the Schanz osteotomy (Fig. 1) was performed by introducing a valgus, and sometimes extension, position to the distal femoral segment but without the proximal displacement of the Lorenz procedure. Whilst this increased pelvic stability, it shared the same effect of abutment from the apex of angulation against the lateral wall of the pelvis, especially when the patient attempted to bring the widely abducted leg parallel to the opposite side. Both techniques therefore induced a limitation of movement from abutment. Milch highlighted this conundrum by introducing the concept of a post-osteotomy angle (angle β in Fig. 1, which is distinct from the angle of abduction at the level of the osteotomy) and its relation to pelvic inclination (angle α in Fig. 1) at the lateral wall of the ischium (Fig. 1). When this angle, whether from Schanz or Lorenz type osteotomies, exceeded pelvic inclination, impingement occurred when the patient attempted to bring the leg into parallel with the contralateral side [2]. The loss of parallelism was in effect an ‘abduction contracture’ and meant some patients, when standing, had to compensate with eversion of the foot and with tilting of the pelvis (consequently producing a relative adduction of the contralateral hip). Whilst this had the desired effect of eliminating the Trendelenburg gait (in which the pelvis tilts in the opposite direction), some surgeons erroneously increased the abduction angle (and consequently the post-osteotomy angulation) to such an excessive degree that it became a disability. Worse still, when the procedure was performed for bilateral cases this made compensation by pelvic tilting impossible [2]. Milch recommended this post-osteotomy angle should lie between 210° and 240°. In so doing, it made the procedure technically demanding as an excessive abduction angle (and correspondingly large post-osteotomy angle) produced stability at the expense of comfortable parallelism of both legs with a level pelvis, whereas one that was insufficiently abducted preserved movement but lost stability.Fig. 1

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