Surgical Dislocation
Indications of surgical dislocation
Ganz surgical hip dislocation is useful in the management of severe hip diseases, providingan unobstructed view of the femoral head and acetabulum [3].
Available therapeutic options range from debridement to total hip arthroplasty.The technique may also be used in the treatment of some fractures of the femoral head and acetabulum and for complex revision hiparthroplasty.[1]
• Femoroacetabular Impingement (FAI) FAI is now widely recognized as a major cause of pain and early osteoarthritis of the hip in young adults [21]. It results from subtle structural abnormalities of the hip, including a reduced anterior femoral headـneck offset and/or an overgrowth of the anterosuperior acetabular rim. [22] …show more content…
During range of motion of thehip,particularly flexion and internal rotation,These abnormalities can produce a mechanical impingement of the femoral head against either the acetabular labrum and/or its adjacent cartilage. This can produce activity-related hip pain in sportive patients, particularly those partaking in activities requiring extreme hip flexion and internal rotation. With time, this repetitive trauma can lead to the development of early osteoarthritis.[22] Two types of FAI,’’cam ‘‘and ’’pincer,‘‘have been described (Fig.23).Their description are based on the skeletal morphology and articular cartilage and labral damage observed during surgical hip dislocations.These morphological variations are not mutually exclusive [22].Cam and pincer lesionsp rarely occur in isolation.Themost common type of FAI occurs from mixed cam and pincer pathology at the anterior femoral neck and anterior superior acetaebular rim. [23] Cam lesions are more common in young active men. The cam is attributed to a nonspherical portion of the femoral head abutting against an acetabular rim. This abutment is most evident in flexion and internal rotation. This cause an outside-in abrasion of the acetabular cartilage with avulsion from the labrum and subchondral bone.This can lead to separation of the cartilage from the antero superior aspect of the labrum.[23] Pincer lesions are more common in middle-aged active women. They occur through repeated contact between a normal femoral head neck junction and an over covered acetabular rim. This results in labral degeneration, intrasubstance ganglion formation,ossification of the acetabular rim,and deepening of the acetabulum.Unlike in cam lesions, the chondral damage is more circumferential.[23] Surgical intervention is indicated for young active patients who experience
Persistent hip pain despite attempts at conservative management[22]. Treatment of FAI should relieve any mechanical impingement as well as treat any intraarticular injury that may be present. The aim of surgery is to improve the clearance for hip motion and alleviate the femoral impingement against the acetabular rim. [24]
Surgical dislocation of the hip provides a safe means to treat FAI.It is possible to fully evaluate the femoral head-neck junction, and to probe the labrum and adjacent acetabular cartilage. A full 360º view of the acetabulum can be obtained . With a blunt probe, the articular cartilage assessed and the integrity of the labrum and the articular cartilage is determined. This approach provides access to perform osteochondroplasty and labral reattachment as needed. By restoring the congruency between the femoral head and the acetabulum, this approach may allow the patient to return to high demand activities without experiencing the symptoms and progressive joint destruction seen with FAI. [22] If acetabular retroversion is contributing to FAI, resection of the excessive anterior rim is performed, after the labrum has been released temporarily and preserved for later refixation (Fig.24). In most instances, the intact labral periphery can be detached from the bony acetabular rim and the degenerated labral base and the osseous overcoverage can be resected down to bleeding bone. The amount of acetabular rim resection is determined on the basis of the magnitude of the damage to the acetabular cartilage and the degree of overcoverage. Most acetabular rim lesions are located anterosuperiorly, close to the anterior inferior iliac spine, and require two to four bone anchors to reattach the labrum. Currently,most titanium anchors are smaller than the absorbable anchors and therefore match the thin anterior rim better. The anchors secure the labrum in a position where it should heal back to the acetabular rim (Fig. 24). It is important to note that the refixation of thetip of the labrum (not labral repair) requires a base of bleeding cancellous bone, which needs to becarefully prepared. In contrast to labral repair in the shoulder, the pullout forces of the acetabular labrum are much lower.[22]
The nonspherical portion of the femoral head is assessed with use of transparent spherical templates.
Usually, the nonspherical part of the head-neck junctionis located anterosuperiorlyand is characterized by a reddishappearance of the cartilaginous surface. Sometimes, it takes some time until the reddening of the impingement cartilage becomes visible. In the periphery of such a nonspherical extension, a small fibrocyst may become visible, indicating the area of maximumimpingement. The location of these impingement cysts is mainly anterolateral and is always distal to the physis. Gentle removal of excess bone and recreation of a smooth femoral neck is preferred. To achieve this goal, small curved chiselsand spherical templates are used (Fig 25). Repetitive intraoperative assessment of femoral head sphericity (with templates) is performed. Excessive bone removal during the offset procedure should be avoided, although a resection of 30% of the neck diameter has been reported not to weaken the femoral neck. Furthermore, excessive resection may compromise the sealing function of the labrum. …show more content…
[22]
Anterior and anterolateral osteochondroplasty is relatively safe because most terminal branches of the MFCA enter the femoral head through vascular foramina at the lateral and posterolateral head-neck junction. Protecting these vessels is essential for preservation of the blood supply to the femoral head [7]. If the nonspherical portion is very lateral and posterolateral, trimming must be carried out from proximal to distal and should stop before off, and it is detached with a knife from inside-out. In this way, even verylaterally and posterolaterally localized offset alterations can be treated. [22]
Sliding the femoral head over the area of labral refixation should be avoided because this could avulse the sutured labrum. With the head reduced, range of motion is reevaluated to determine if flexion-internal rotation still leads to FAI. [22]
• Acetabular fractures
Surgical treatment of displaced acetabular fractures can cause complications like posttraumatic osteoarthrosis, osteonecrosis of the femoral head, and heterotopic ossification 9HO) [25].
For proper management of displaced fractures, the joint should be exposed for accurate assessment of anatomic reduction, extra-articular placement of fixation screws, and complete removal offree fragments [26]. Precise restoration of the articular surface and joints congruity are the primary goals in treating displaced acetabular fractures with open reduction and internal fixation. Prognosis mainly depends on the accuracy of the
reduction.[25]
Open reduction and internal fixation through a modified Kocher-Langenbeck approach with trochanteric flip osteotomy and surgical dislocation of the femoral head in the anterior direction has advantages:[26]
• Direct intra-articular assessment with proper reduction of free and impacted fragments.
• Immediate and reliable extra-articular screw placement for anterior column or posterior wall fragments very close to the joint.
• Small intra-articular fragment which can later cause bone block can be directly visualized and removed.
• Intraoperatively it is found that reduction judged to be anatomically reduced from the extra-articular fracture lines,proved to be incorrect at subsequent intra-articular inspection after surgical femoral head dislocation.
• No danger to vascularity of femoral head.
• Ho is minimal and mainly restricted to the great trochanteric area without functional restrictions. Debridement of gluteus minimus muscle which is found traumatized and may cause Ho.
Advantageous over other approaches:
• It is more advantageous over the standard Kocher-Langenbeck approach by giving good exposure (especially in posterior wall in the dome area,posterior fracture-dislocation with intra-articular fragments/ femoral head fractures (Fig. 26) and T-fractures) ; but the standard Kocher-Langenbeck allows restricted intra-articular assessment even with strong traction on the femur ; and limited access to the superior acetabular rim in case of a cranial extension of the posterior wall fracture.
• It preserves abductor strength (which may be lost with excessive retraction of abductors to see dome area in classical posterior approach)with reliable healing of osteotomy (in contrast to conventional trochanteric osteotomy).
Disadvantages (limitations):
• Thelateral decubitus position without traction table, while performing this approach, may hinder in fracture reduction and manual tractions may be needed.
• A limitation of this approach is that large displaced anterior column fractures medial to the iliopubic eminence cannot sufficiently be reduced and may require an additional approach.
• Pediatric Hip Diseases Ganz surgical hip dislocation is useful in the management of pediatric hip diseases including hereditary multiple exostoses, slipped capital femoral epiphysis,Legg-Calve-Perthes disease, osteoid osteoma,pigmented villonodular synovitis, and neonatal septic hip sequelae.
The surgical dislocation approach is useful in assessing and treating proximal femoral hip deformities commonly due to pediatric conditions. Through this approach, femoral head-neck osteoplasty, intertrochanteric osteotomy, femoral head-neck osteoplasty plus intertrochanteric osteotomy, femoral neck osteotomy, osteochondroplasty, proximal femoral osteotomy, synovectomy, and core decompression of the femoral head can be performed.
•
Ganz surgical hip dislocation is useful in the management of severe hip diseases, providingan unobstructed view of the femoral head and acetabulum [3].
Available therapeutic options range from debridement to total hip arthroplasty.The technique may also be used in the treatment of some fractures of the femoral head and acetabulum and for complex revision hiparthroplasty.[1]
• Femoroacetabular Impingement (FAI) FAI is now widely recognized as a major cause of pain and early osteoarthritis of the hip in young adults [21]. It results from subtle structural abnormalities of the hip, including a reduced anterior femoral headـneck offset and/or an overgrowth of the anterosuperior acetabular rim. [22] …show more content…
During range of motion of thehip,particularly flexion and internal rotation,These abnormalities can produce a mechanical impingement of the femoral head against either the acetabular labrum and/or its adjacent cartilage. This can produce activity-related hip pain in sportive patients, particularly those partaking in activities requiring extreme hip flexion and internal rotation. With time, this repetitive trauma can lead to the development of early osteoarthritis.[22] Two types of FAI,’’cam ‘‘and ’’pincer,‘‘have been described (Fig.23).Their description are based on the skeletal morphology and articular cartilage and labral damage observed during surgical hip dislocations.These morphological variations are not mutually exclusive [22].Cam and pincer lesionsp rarely occur in isolation.Themost common type of FAI occurs from mixed cam and pincer pathology at the anterior femoral neck and anterior superior acetaebular rim. [23] Cam lesions are more common in young active men. The cam is attributed to a nonspherical portion of the femoral head abutting against an acetabular rim. This abutment is most evident in flexion and internal rotation. This cause an outside-in abrasion of the acetabular cartilage with avulsion from the labrum and subchondral bone.This can lead to separation of the cartilage from the antero superior aspect of the labrum.[23] Pincer lesions are more common in middle-aged active women. They occur through repeated contact between a normal femoral head neck junction and an over covered acetabular rim. This results in labral degeneration, intrasubstance ganglion formation,ossification of the acetabular rim,and deepening of the acetabulum.Unlike in cam lesions, the chondral damage is more circumferential.[23] Surgical intervention is indicated for young active patients who experience
Persistent hip pain despite attempts at conservative management[22]. Treatment of FAI should relieve any mechanical impingement as well as treat any intraarticular injury that may be present. The aim of surgery is to improve the clearance for hip motion and alleviate the femoral impingement against the acetabular rim. [24]
Surgical dislocation of the hip provides a safe means to treat FAI.It is possible to fully evaluate the femoral head-neck junction, and to probe the labrum and adjacent acetabular cartilage. A full 360º view of the acetabulum can be obtained . With a blunt probe, the articular cartilage assessed and the integrity of the labrum and the articular cartilage is determined. This approach provides access to perform osteochondroplasty and labral reattachment as needed. By restoring the congruency between the femoral head and the acetabulum, this approach may allow the patient to return to high demand activities without experiencing the symptoms and progressive joint destruction seen with FAI. [22] If acetabular retroversion is contributing to FAI, resection of the excessive anterior rim is performed, after the labrum has been released temporarily and preserved for later refixation (Fig.24). In most instances, the intact labral periphery can be detached from the bony acetabular rim and the degenerated labral base and the osseous overcoverage can be resected down to bleeding bone. The amount of acetabular rim resection is determined on the basis of the magnitude of the damage to the acetabular cartilage and the degree of overcoverage. Most acetabular rim lesions are located anterosuperiorly, close to the anterior inferior iliac spine, and require two to four bone anchors to reattach the labrum. Currently,most titanium anchors are smaller than the absorbable anchors and therefore match the thin anterior rim better. The anchors secure the labrum in a position where it should heal back to the acetabular rim (Fig. 24). It is important to note that the refixation of thetip of the labrum (not labral repair) requires a base of bleeding cancellous bone, which needs to becarefully prepared. In contrast to labral repair in the shoulder, the pullout forces of the acetabular labrum are much lower.[22]
The nonspherical portion of the femoral head is assessed with use of transparent spherical templates.
Usually, the nonspherical part of the head-neck junctionis located anterosuperiorlyand is characterized by a reddishappearance of the cartilaginous surface. Sometimes, it takes some time until the reddening of the impingement cartilage becomes visible. In the periphery of such a nonspherical extension, a small fibrocyst may become visible, indicating the area of maximumimpingement. The location of these impingement cysts is mainly anterolateral and is always distal to the physis. Gentle removal of excess bone and recreation of a smooth femoral neck is preferred. To achieve this goal, small curved chiselsand spherical templates are used (Fig 25). Repetitive intraoperative assessment of femoral head sphericity (with templates) is performed. Excessive bone removal during the offset procedure should be avoided, although a resection of 30% of the neck diameter has been reported not to weaken the femoral neck. Furthermore, excessive resection may compromise the sealing function of the labrum. …show more content…
[22]
Anterior and anterolateral osteochondroplasty is relatively safe because most terminal branches of the MFCA enter the femoral head through vascular foramina at the lateral and posterolateral head-neck junction. Protecting these vessels is essential for preservation of the blood supply to the femoral head [7]. If the nonspherical portion is very lateral and posterolateral, trimming must be carried out from proximal to distal and should stop before off, and it is detached with a knife from inside-out. In this way, even verylaterally and posterolaterally localized offset alterations can be treated. [22]
Sliding the femoral head over the area of labral refixation should be avoided because this could avulse the sutured labrum. With the head reduced, range of motion is reevaluated to determine if flexion-internal rotation still leads to FAI. [22]
• Acetabular fractures
Surgical treatment of displaced acetabular fractures can cause complications like posttraumatic osteoarthrosis, osteonecrosis of the femoral head, and heterotopic ossification 9HO) [25].
For proper management of displaced fractures, the joint should be exposed for accurate assessment of anatomic reduction, extra-articular placement of fixation screws, and complete removal offree fragments [26]. Precise restoration of the articular surface and joints congruity are the primary goals in treating displaced acetabular fractures with open reduction and internal fixation. Prognosis mainly depends on the accuracy of the
reduction.[25]
Open reduction and internal fixation through a modified Kocher-Langenbeck approach with trochanteric flip osteotomy and surgical dislocation of the femoral head in the anterior direction has advantages:[26]
• Direct intra-articular assessment with proper reduction of free and impacted fragments.
• Immediate and reliable extra-articular screw placement for anterior column or posterior wall fragments very close to the joint.
• Small intra-articular fragment which can later cause bone block can be directly visualized and removed.
• Intraoperatively it is found that reduction judged to be anatomically reduced from the extra-articular fracture lines,proved to be incorrect at subsequent intra-articular inspection after surgical femoral head dislocation.
• No danger to vascularity of femoral head.
• Ho is minimal and mainly restricted to the great trochanteric area without functional restrictions. Debridement of gluteus minimus muscle which is found traumatized and may cause Ho.
Advantageous over other approaches:
• It is more advantageous over the standard Kocher-Langenbeck approach by giving good exposure (especially in posterior wall in the dome area,posterior fracture-dislocation with intra-articular fragments/ femoral head fractures (Fig. 26) and T-fractures) ; but the standard Kocher-Langenbeck allows restricted intra-articular assessment even with strong traction on the femur ; and limited access to the superior acetabular rim in case of a cranial extension of the posterior wall fracture.
• It preserves abductor strength (which may be lost with excessive retraction of abductors to see dome area in classical posterior approach)with reliable healing of osteotomy (in contrast to conventional trochanteric osteotomy).
Disadvantages (limitations):
• Thelateral decubitus position without traction table, while performing this approach, may hinder in fracture reduction and manual tractions may be needed.
• A limitation of this approach is that large displaced anterior column fractures medial to the iliopubic eminence cannot sufficiently be reduced and may require an additional approach.
• Pediatric Hip Diseases Ganz surgical hip dislocation is useful in the management of pediatric hip diseases including hereditary multiple exostoses, slipped capital femoral epiphysis,Legg-Calve-Perthes disease, osteoid osteoma,pigmented villonodular synovitis, and neonatal septic hip sequelae.
The surgical dislocation approach is useful in assessing and treating proximal femoral hip deformities commonly due to pediatric conditions. Through this approach, femoral head-neck osteoplasty, intertrochanteric osteotomy, femoral head-neck osteoplasty plus intertrochanteric osteotomy, femoral neck osteotomy, osteochondroplasty, proximal femoral osteotomy, synovectomy, and core decompression of the femoral head can be performed.
•