Practice Tips

A retention stitch technique for vaginal prolapse repair in cattle

The Bühner stitch technique for circumferential burial of suture material around the vestibule of the reproductive tract was originally described for repair of vaginal prolapse in cattle (1) and has subsequently been described in many large animal surgical texts. It is widely used by veterinarians as the technique of choice for repair of vaginal prolapse in beef cattle.

Complications can include: peri-vulvar edema and cellulitis, pain and straining, urine pooling, stitch failure and re-prolapse, phlegmon, and occasionally malignant edema. The purpose of this practice tip is to describe a modification of this technique for vaginal prolapse that is less prone to stitch failure and re-prolapse in beef cattle. This modification is a suitable option where previous retention suturing has failed or where poor perineum tissue strength due to obesity is suspect in feeder cows and heifers.

Following epidural anesthesia, and cleansing of the perineum and prolapsed tissue, the prolapse is reduced and replaced in normal anatomical position within the abdomen prior to placement of the retention suture. The suture material (vaginal tape) and the suture needle (Bühner Prolapse Needle) are the same as those commonly used for the Bühner technique, but the length of suture material needed is about 20% to 30% longer than what would be required for the Bühner technique. Modification of the traditional Bühner technique is made by incorporating partial, exposed, horizontal mattress-like sutures within the Bühner stitch pattern as follows.

Step 1. The first entry point of the prolapse needle begins in the fine-haired skin portion of the perineum above and lateral to the dorsal commissure of the vulva. The prolapse needle is directed horizontally, from one side of the vulva to the other, staying beneath the skin and travelling through the perineal body that lies between the rectum and vagina. Care is taken not to penetrate the rectum or the vaginal vaults. After this pass, the protruding end of the prolapse needle is threaded with vaginal tape and then withdrawn back out through the entry point (Figure 1).

Figure 1.

Horizontal needle direction.

Step 2. The second entry point of the needle is in the fine-haired skin below and slightly lateral to the ventral commissure of the vulva. The needle is directed dorsally and subcutaneously along the lateral side of the vulvar lip to exit 2 to 3 cm below the exit point of the horizontally placed suture. While in this position, the eye of the needle is threaded with the end of the vaginal tape that exits on the same side of the vulva. The threaded needle and the tail of the tape are then withdrawn out of the second entry point. The non-dominant hand maintains control of the vaginal tape on the contralateral side of the vulva to prevent pulling out the free end of the tape on that side (Figure 2).

Figure 2.

Lateral mattress suture placement.

Step 3. The same procedure (Step 2) is repeated for the contralateral side of the vulva using a third entry point below the ventral commissure of the vulva and 2 to 3 cm lateral to that made at the start of step 2. This creates another laterally placed horizontal mattress suture on the other side and near the top of the dorsal commissure of the vulva. The bottom ends of the vaginal tape are tensioned and then tied in usual fashion. The end-product is a partially buried suture that has exposed horizontal mattress-like sutures on either side of the dorsal commissure and one below the ventral commissure of the vulva. Tightening the suture creates a puckering of the vulva with tension occurring primarily on the exposed suture sites which lie in the thicker skin on the margins of the perineum (Figure 3).

Figure 3.

Tensioning and tying.

Slightly more perineal and vulvar swelling is seen postoperatively with this modification, but if the suture is properly placed and tensioned, it does not seem to cause additional animal welfare or production concern. It is particularly important to pre-soak braided vaginal tape with an appropriate antibacterial solution such as proviodine in addition to following usual pre-surgical cleansing and post-operative care in order to reduce postoperative cellulitis that is subsequent to the wicking action of percutaneous braided material. Additional post-surgical scar formation is also seen surrounding this suture pattern if the suture is left in for weeks, but this appears to enhance rather than hinder the long-term effectiveness of this pattern for vaginal retention.

This suture modification seems to address a hypothesis of why properly placed Bühner stitches sometimes fail. Properly placed Bühner vaginal retention stitches that fail and result in re-prolapse often rip through the dorsal vestibular or vaginal wall. Whether this is primarily due to the small, weak mass of the perineal body included in the Bühner stitch technique or due to the unique upward thrust of the reproductive tract in a straining prolapse victim is unknown. This hypothesis assumes that properly placed Bühner stitches bury the suture within a small area of the perineal body and around the vestibule while attempting to replicate function of the vestibular muscle of the vagina. In the technique described, the inclusion of the horizontal mattress-like sutures in the pattern dramatically changes the downward tension on the dorsal vestibular area during straining and directs it towards tissues (thicker skin) that have superior holding strength. It may also permit inclusion of a larger volume of the perineal body within the suture pattern and thus could account for a reduced stitch failure with this technique.