1887

The hip

image of The hip
GBP
Online Access: GBP25.00 + VAT
BSAVA Library Pass Buy a pass

Abstract

Conditions affecting the hip, or coxofemoral joint, are common in small animal practice, especially in younger animals where a variety of developmental conditions can be encountered. This chapter covers the clinical anatomy, clinical examination, diagnostic investigations, and management of a range of conditions affecting the hip. Includes . : Craniolateral approach to the hip; Dorsal approach to the hip; Ventral approach to the hip; Hip toggle; Iliofemoral suture; Transarticular pin; Dorsal capsular sling; Femoral head and neck excision.

Loading full text...

Full text loading...

/content/chapter/10.22233/9781910443286.chap22

Figures

Image of 22.1
22.1 Cadaveric image of the acetabulum of a dog, showing the weight-bearing lunate surface and the ventromedially located acetabular fossa. The fossa is the origin of the ligament of the femoral head.
Image of 22.2
22.2 Cadaveric images of the proximal femur of a dog. (a) The neck is anteverted by around 15–20 degrees (angle α), which corresponds to the retroversion of the acetabulum. (b) The femoral neck is inclined with respect to the femoral diaphysis by about 140 degrees (angleβ). (b)
Image of 22.3
22.3 Arterial blood supply to the femoral head and neck of a dog, showing the femoral artery (A), lateral circumflex femoral artery (B), medial circumflex femoral artery (C), and caudal gluteal artery (D). Note the capsular vessels inserting around the periphery of the epiphysis which supply the femoral head in the juvenile animal. (Reproduced from the BSAVA Manual of Small Animal Fracture Repair and Management)
Image of 22.4
22.4 The sciatic nerve (green line) crosses the ilium at the sciatic notch and runs caudodorsal to the hip. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.5
22.5 (a) The palpable greater trochanter (*) in a normal dog is located ventral to an imaginary line between the wing of the ilium and the tuber ischium (black line). (b) If a dorsal luxation of the hip has occurred, the greater trochanter is located further dorsally.
Image of 22.6
22.6 In a normal hip the femoral head is a fixed point; caudal rotation of the femur leads to narrowing of the gap between the greater trochanter and the tuber ischium (black arrow), which causes displacement of the examiner’s thumb from the sciatic notch. If a dorsal luxation of the hip has occurred, caudal rotation of the femur leads to cranial movement of the unrestrained femoral head; the greater trochanter does not move caudally, and the examiner’s thumb is not displaced.
Image of 22.7
22.7 The Ortolani manoeuvre performed under heavy sedation or general anaesthesia.  (a) With the hip held at a standing angle, an axial force is applied along the femur which causes subluxation of the dysplastic hip. (b) While the axial force is maintained the limb is abducted, eventually causing reduction of the femoral head; this is the reduction angle (with respect to the vertical). (c) The axial force is maintained and the limb is adducted, and the femoral head subluxates; this is the luxation angle (with respect to the vertical). Note that in (a) and (b) the dog is shown in lateral recumbency and in (c) the dog is shown in dorsal recumbency. (a) (b) Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.8
22.8 (a) Lateral and (b) ventrodorsal hip-extended radiographs of the pelvis of a Labrador Retriever. Note that the wings of the ilia and the obturator foramina are symmetrical on the ventrodorsal view, indicating perfect positioning. Mild degenerative changes can be appreciated affecting the hips. (a) (b)
Image of 22.9
22.9 (a) Labrador Retriever positioned for a caudocranial radiograph of the femur. This view allows the femur to be positioned parallel to the radiographic cassette, avoiding foreshortening of the bone on (b) the radiograph. (a) (b)
Image of 22.10
22.10 (a) Ventrodorsal hip-extended radiograph and (b) PennHIP view of the same dog. Hip laxity is more easily appreciated on the PennHIP view. The distraction index (DI) is calculated after drawing circles around the femoral head and over the acetabulum. The distance between the centres of the two circles ‘d’ is then measured and compared with the radius of the femoral head; DI = d/r. (Courtesy of Professor Gail Smith)
Image of 22.11
22.11 Transverse computed tomography (CT) image of the hips of a dog. The morphology of the joints can be evaluated in detail.
Image of 22.12
22.12 Arthrocentesis of the hip. The needle is introduced craniodorsal to the greater trochanter (indicated by the dotted line on the cadaver) and directed towards the joint. (a) (b)
Image of 22.13
22.13 Cadaveric images of a crossbreed dog with hip dysplasia. New bone has formed (a) within the acetabular fossa and on the dorsal acetabular rim, and (b) around the margin of the femoral head.
Image of 22.14
22.14 Ventrodorsal hip-extended pelvic view of a 12-month-old dog with hip dysplasia. The Norberg angle (NA) for each hip is the angle between a line connecting the centres of the femoral heads, and lines drawn from the centre of each femoral head to the ipsilateral cranial effective acetabular rim. A ‘Morgan’s line’ can also be appreciated (arrowed); this is caused by early osteophyte formation at the insertion of the joint capsule.
Image of 22.15
22.15 The percentage femoral head coverage (%FHC) (shaded area) is the proportion of the femoral head medial to the dorsal acetabular rim (dotted line). Values less than 50% are considered abnormal.
Image of 22.16
22.16 Ventrodorsal hip-extended radiograph of a 4-year-old German Shepherd Dog with severe hip dysplasia. Note the marked subluxation, remodelling of the acetabulum and femoral head, and extensive osteophyte formation. (a) (b)
Image of 22.17
22.17 Triple pelvic osteotomy. (a) The acetabular fragment is acutely rotated along its long axis (arrowed) thus improving dorsal coverage of the femoral head. (b) The ilial osteotomy is stabilized using a plate and bone screws. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.18
22.18 Juvenile pubic symphysiodesis. Thermal injury to the pubic symphysis (straight arrow) prevents further widening of the ventral aspect of the pelvis. As the dorsal aspect continues to grow, the acetabulae rotate ventrally (curved arrows), improving dorsal femoral head coverage. (a) (b)
Image of 22.19
22.19 (a) Ventrodorsal view of the left hip of an 8-month-old West Highland White Terrier. Subtle radiolucency of the femoral head can be appreciated, indicative of early avascular necrosis of the femoral head (ANFH); in addition, the joint space appears slightly widened (arrowed). (b) Subchondral bone loss (arrowed) is much more obvious on a CT scan.
Image of 22.20
22.20 Ventrodorsal pelvic radiograph of an 11-month-old Yorkshire Terrier with advanced ANFH showing marked remodelling of the right femoral head and neck. (a) (b)
Image of 22.21
22.21 (a) Ventrodorsal pelvic radiograph of a 3-year-old Staffordshire Bull Terrier. The left hip is luxated and an avulsion fracture of the femoral head is present. (b) The lateral view shows the luxation is in a dorsal direction. (a) (b)
Image of 22.22
22.22 (a–b) Closed reduction of a dorsal hip luxation. The patient is secured on the table using a sling placed around the pelvis and dependent limb. The affected limb is externally rotated and pulled distally and then internally rotated to reduce the hip. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.23
22.23 An Ehmer sling is used to maintain reduction of the hip. Adhesive dressing material is placed between the distal thigh and metatarsus, passing medially to the crus in both directions. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.24
22.24 A transarticular pin inserted to maintain hip reduction in a dog.
Image of 22.25
22.25 Dorsal capsular sling. Screws are placed in the dorsal acetabular rim, and sutures passed from these screws to bone tunnels drilled in the femoral neck. The joint is usually approached via a trochanteric osteotomy. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.26
22.26 Postoperative radiograph showing placement of a ventral acetabular plate to maintain reduction following ventral luxation as a complication of total hip replacement. (a) (b)
Image of 22.27
22.27 (a) Ventrodorsal hip-extended and (b) ‘frog-legged’ pelvic radiographs showing a slipped femoral capital epiphysis on the left. Subtle widening of the left capital physis is evident on the hip-extended view (arrowed); the lesion is more obvious on the flexed view (arrowed). The lesions are subtle but comparison of the affected left to the normal right hip shows that the appearance of the anatomical relationship between the femoral head and neck is different.
Image of 22.28
22.28 Ventrodorsal pelvic radiograph showing a chronic slipped femoral capital epiphysis. Marked lytic remodelling of the femoral neck on the right can be appreciated. (a) (b)
Image of 22.29
22.29 (a) Ventrodorsal pelvic radiograph of a 5-year-old Dobermann with heterotopic osteochondrofibrosis, showing irregular mineralization of the ischium (arrowed). (b) The changes are more obvious on a CT scan (arrowed). (a) (b)
Image of 22.30
22.30 (a) Postoperative ventrodorsal pelvic radiograph following femoral head and neck excision. (b) The excised portion of bone viewed from a caudal direction (left) and a medial direction (right). Note the obliquity of the osteotomy at the femoral neck.
Image of 22.31
22.31 Postoperative ventrodorsal pelvic radiograph following bilateral hybrid total hip replacement in a Springer Spaniel. The acetabular components are cementless, the femoral components are cemented.
Image of 22.32
22.32 Patient positioning for a ventrodorsal view of the hip and pelvis; the black dot indicates the centring point. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.33
22.33 Patient positioning for a lateral view of the hip and pelvis. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.34
22.34 Patient positioning for a flexed (frog-legged) ventrodorsal view of the hip and pelvis. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.35
22.35 Patient positioning for a lateral view of one hip joint. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.36
22.36 (a) Following the skin incision, the superficial layer of the fascia lata is incised along the cranial border of the biceps femoris muscle which is retracted caudally. The deep layer of the fascia lata is then incised along the junction between the tensor fasciae latae and the superficial gluteal muscles; this incision is extended distally, caudal to the tensor fasciae latae (dotted line). (b) The superficial and middle gluteal muscles are retracted dorsally to reveal the deep gluteal tendon. To improve exposure, this can be incised using an inverse ‘L’ shaped incision if necessary (dotted line). (c) The joint capsule is incised parallel to the femoral neck. External rotation of the femur and placement of Hohmann retractors allows exposure of the femoral head and neck. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.37
22.37 Osteotomy of the greater trochanter. (a) Following retraction of the biceps femoris and superficial gluteal muscles, an instrument is placed medial to the greater trochanter deep to the insertions of the middle and deep gluteal tendons. (b) A 45-degree osteotomy of the greater trochanter is performed, starting at the base of the trochanter and aiming proximomedially. Osteotomy of the greater trochanter. (c) The greater trochanter can then be retracted proximally. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.38
22.38 Toggle stabilization for hip luxation. (a) A bone tunnel is drilled along the femoral neck, running from the base of the greater trochanter and exiting the bone at the fovea capitis of the femoral head. (b) A hole is drilled in the acetabular fossa. (c) The toggle rod is placed through the acetabular hole into the pelvic canal. Pulling on the sutures allows the rod to be positioned against the medial acetabular wall. (d) The suture is passed through the femoral bone tunnel. (e) Following reduction of the hip, the suture is secured laterally to a button. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.39
22.39 Iliofemoral suture. The suture is placed from the greater trochanter to the pelvis in the region of the origin of the rectus femoris muscle. Tightening the suture with internal rotation of the femur maintains reduction of the hip. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.40
22.40 Transarticular pin. The pin is driven through a pilot hole drilled along the femoral neck. The entry point for the pin is the base of the greater trochanter; the exit point is the fovea capitis. (a) Following reduction of the hip, the pin is driven just through the medial acetabular wall. (b) The end of the pin is then bent over to prevent migration into the pelvis. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.41
22.41 Following a dorsolateral approach to the hip, the greater trochanter can be reattached in a slightly caudal and distal location in larger dogs. This increases tension in the gluteal tendons, internally rotating the hip and improving stability. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.
Image of 22.42
22.42 Femoral head and neck excision. It is very important that the femur is externally rotated by 90 degrees and oriented so the stifle is pointing at the ceiling of the room. The osteotomy is made along a line starting medial to the greater trochanter and ending immediately proximal to the lesser trochanter. Drawn by S.J. Elmhurst BA Hons (www.livingart.org.uk) and reproduced with her permission.

More like this

/content/chapter/10.22233/9781910443286.chap22
dcterms_title,dcterms_description
-contentType:Journal
5
5
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error