6: The Pelvis and Hip Joint


The Pelvis and Hip Joint





Approach to the Wing of the Ilium and Dorsal Aspect of the Sacrum



Based on a Procedure of Alexander, Archibald, and Cawley2






Description of the Procedure




The skin incision starts cranially over the cranial dorsal iliac spine and continues caudally parallel to the midline to near the hip joint. Subcutaneous tissues and gluteal fascia and fat are incised on the same line to expose the cranial and caudal dorsal iliac spines.


If only the lateral (gluteal) surface of the wing of the ilium needs to be exposed, as for fractures or cancellous bone collection, an incision is made in the periosteal origin of the middle gluteal muscle on the lateral edge of the ilium near the cranial dorsal iliac spine and ending beyond the caudal dorsal spine. If the sacrum must also be exposed, a second incision is made in the periosteal origin of the sacrospinalis muscle, at the medial edge of the ilium. These incisions merge as they continue caudally, and it will be necessary to transect some fibers of the superficial gluteal muscle in this region.


The middle gluteal muscle is elevated subperiosteally in young animals, or simply scraped from its origin on the ilium in older animals. The elevation continues caudally to the caudal dorsal iliac spine. Continuing further, caudal dissection will result in severance of the cranial gluteal artery, vein, and nerve. Similar elevation of the sacrospinalis muscle on the medial side of the ilium gives limited exposure of the dorsal surface of the sacrum. Muscular elevation on the sacrum should be confined to the area lateral to the intermediate crests to avoid damage to dorsal nerve roots emerging through the dorsal foramina of the sacrum.





Approach to the Ilium Through a Lateral Incision



Based on a Procedure of Hohn and Janes22




Alternative Approach


The dorsal approach (see Plate 63) can be used if exposure of only the iliac wing is needed.




Description of the Procedure




The skin incision extends from the center of the iliac crest and ends just caudal and distal to the greater trochanter.


Subcutaneous tissues, gluteal fat, and superficial fascia are incised and elevated with the skin. Incision of the deep gluteal fascia on the same line as the skin allows incision of the intermuscular septum between the tensor fasciae latae and middle gluteal muscles. This incision extends from the ventral iliac spine to the cranial border of the biceps femoris muscle. Fascia is also incised along the cranial border of the biceps femoris muscle to create a T-shaped fascial incision.


Retraction of the middle gluteal muscle exposes the deep gluteal muscle and a portion of the iliac shaft.


An incision is made in the origin of the middle gluteal muscle on the ilium, starting at the caudal ventral iliac spine and continuing cranially and dorsally as needed. Some sharp dissection may be needed between the middle gluteal and sartorius muscles, the fibers of which blend together. The iliolumbar vessels are ligated at the ventral edge of the ilium. An incision is started in the origin of the deep gluteal muscle to allow caudal retraction of this muscle.


Subperiosteal elevation of the gluteal muscles exposes the crest, wing, and shaft of the ilium.


    Maximal exposure of the shaft of the ilium, cranial to the acetabulum, may necessitate sacrificing branches of the cranial gluteal artery, vein, and nerve that supply the tensor fasciae latae muscle. Elevation of the iliacus muscle along the ventral border of the iliac shaft (see Plate 65) usually results in severing a nutrient artery on the ventral aspect of the shaft. The severed artery must then be cauterized or plugged with bone wax.





Precautions


Consideration must be given to the sciatic nerve when retracting the gluteal muscles (see Plate 64E) or using bone-holding forceps on the ilium. The nerve lies close to the dorsomedial aspect of the iliac shaft. With care in retracting, the cranial gluteal vessels and nerve can usually be preserved.




Approach to the Ventral Aspect of the Sacrum



Based on a Procedure of Montavon, Boudrieau, and Hohn27




Alternative Approach


The approach to the sacroiliac joint through a dorsal incision (see Plate 63) allows superior visualization of the sacral wing in sacroiliac luxation. However, a disadvantage of the dorsal approach is that it cannot be extended caudally for a combined exposure of the ilial shaft and hip joint.




Description of the Procedure


This approach is an extension of Approach to the Ilium Through a Lateral Incision and should be performed as shown in Plate 64A-C. Elevation of the deep gluteal muscle, as shown in Plate 64D and E, is unnecessary.







Approach to the Craniodorsal Aspect of the Hip Joint Through a Craniolateral Incision in the Dog



Based on Procedures of Archibald, Brown, Nasti, and Medway3 and Brown and Rosen6






Description of the Procedure




The skin incision is centered at the level of the greater trochanter and lies over the cranial border of the shaft of the femur. Distally, it extends one third to one half the length of the femur; proximally, it curves slightly cranially to end just short of the dorsal midline. When performing the total hip replacement procedure, the skin incision is modified to facilitate femoral reaming; proximally it curves caudally over the trochanter and toward the base of the tail.


The skin margins are undermined and retracted. An incision is made through the superficial leaf of the fascia lata, along the cranial border of the biceps femoris muscle.


The biceps femoris muscle is retracted caudally to allow incision in the deep leaf of the fascia lata to free the insertion of the tensor fasciae latae muscle. The incision continues proximally through the intermuscular septum between the cranial border of the superficial gluteal muscle and the tensor fasciae latae muscle.


The fascia lata and the attached tensor fasciae latae muscle are retracted cranially and the biceps caudally. Blunt dissection and separation along the neck of the femur with the fingertip allows visualization of a triangle bounded dorsally by the middle and deep gluteal muscles, laterally by the vastus lateralis muscle, and medially by the rectus femoris muscle.


The joint capsule is covered by areolar tissue, which must be cleared away by blunt dissection. An incision is then made in the joint capsule and continued laterally along the femoral neck through the origin of the vastus lateralis muscle on the neck and lesser trochanter. Exposure can be improved by tenotomy of a portion of the deep gluteal tendon close to the trochanter, leaving enough tendon on the bone to allow suturing. The muscle is split proximally, parallel to its fibers, and the pedicle is allowed to retract.


The origin of the vastus lateralis muscle is elevated from the femoral neck and reflected distally. The muscle comes free most easily if the elevation proceeds from distal to proximal. This elevation can be subperiosteal in the immature animal or extraperiosteal in the mature animal. Hohmann retractors are placed intracapsularly ventral and caudal to the femoral neck to allow visualization of the femoral head. Caution is needed to be certain that the caudal retractor is intracapsular, or at least between the deep gluteal muscle and the femoral neck, to avoid entrapping the sciatic nerve on the caudodorsal surface of the deep gluteal muscle.




Closure


One or two mattress sutures (see Figure 21B) or a pulley suture (see Figure 21D) are placed in the deep gluteal tendon incision, and the origin of the vastus lateralis muscle is sutured to the cranial edge of the deep gluteal muscle. Continuous sutures are placed in the insertion of the tensor fasciae latae muscle distally and are continued proximally along the cranial border of the superficial gluteal muscle. The superficial leaf of the fascia lata distally and the gluteal fascia proximally are closed to the cranial border of the biceps femoris with a continuous pattern. The rest of the incision is closed routinely in layers.



Precautions


Dorsal to the hip joint, the sciatic nerve emerges from the ischiatic foramen under the superficial gluteal muscle. It passes caudal to the deep gluteal muscle, across the gemelli and internal obturator muscles, then passes down the thigh deep to the biceps femoris muscle. To reduce the risk of damage to the sciatic nerve, sharp retractors such as the Meyerding should not be used to retract the biceps femoris muscle.


Stay updated, free articles. Join our Telegram channel

Mar 31, 2017 | Posted by in SUGERY, ORTHOPEDICS & ANESTHESIA | Comments Off on 6: The Pelvis and Hip Joint

Full access? Get Clinical Tree

Get Clinical Tree app for offline access