Spay neuter surgery involves a combination of repetitive movements that can at times require force, or may be performed with awkward positioning of the hands and wrists. Each of these factors alone is only moderately associated with pain, but put together there is a strong association with hand and wrist pain.
In any high volume workplace, there will be repetition; it’s unavoidable. Fortunately, many high-volume surgery techniques can reduce some of the repetition.
For example:
- Pedicle ties mean fewer suture knots (i.e., less repetition of knot-tying motion)
- Shorter incisions mean fewer sutures placed, and fewer knots tied
- Efficient technique in general means less wasted motion
In case you are not familiar with some of these techniques, I have included some links and videos so that you can learn about them.
Pedicle Ties are an autoligation technique used in feline spay surgery on the ovarian pedicles. For a peer-reviewed study on the safety of pedicle ties, see this article by Miller et al. The abstract is available here. Pedicle ties are a safe alternative to the use of sutures for ligation in cats, and can decrease surgery time. And shorter surgery time means less trauma for the cat and for the surgeon.
Here is a video of several pedicle ties:
Shorter spay incisions are achieved with practice. The incision needs only to be long enough to deliver the uterus through the opening. Use of a spay hook (on cats and dogs, not other species) is helpful in allowing a smaller incision. It is worth the practice time it takes to be able to make a short incision. As with pedicle ties, short incisions allow for shorter surgery time, less repetition, and less trauma to the animal and the veterinarian.
Here is a video of a cat spay using a short incision and a pedicle tie:
Want to learn more about high volume techniques? Check out Humane Alliance’s E-Learning resources.
So, high volume techniques can decrease the number of repetitions of any given action– but how else can a surgeon lower the risk of hand and wrist pain?
Sustained awkward or tiring positions can lead to discomfort. The pinch grip used for thumb forceps is a common example of an awkward, tiring grip. Some spay neuter vets minimize the use of thumb forceps during closure. This reduces the trauma to skin edges, and also reduces strain from the pinch grip, so it can be a win-win situation.
Other awkward or extreme postures are rarely necessary in spay and neuter surgery, but they may be something that you are using without really realizing it. This is a great reason to get video of yourself doing surgery.
You can find awkward spay pictures from the internet (see one below) that show a large amount of wrist flexion or extension. These positions are all OK, as long as they are comfortable and not sustained or repeated for a lot of time. If they become uncomfortable, or if the surgeon is spending a lot of time in extreme or awkward positions, then it’s time to think of other ways to perform the same surgical tasks.
Here are some arm positions during suturing that are near the extremes of their ranges of motion. Again, there is nothing inherently wrong with having positions that are at the end of the range of motion. But, if they become uncomfortable or inefficient, or they are sustained or repeated often, then the surgeon will need to try alternative positions to achieve the same tasks.
(These vets have wires and stick-on electrodes on their arms because they were a part of my Masters’ research project).
There are a lot of different ways that spay neuter vets hold their needle holders. Some spay neuter vets swear by using the palm grasp, whereas others have never used it. It turns out that the amount of muscle use and the range of motion is so variable between different vets that I can’t really make generalizations about muscle strain.
This is another case where photos and video are helpful. If the motions of surgery and grasping instruments are uncomfortable, then that may be a cue for the surgeon to consider learning a different grasp style and seeing if the changes in grasp take strain off the uncomfortable body areas.
There are also times when surgical technique can change your whole body posture. In this illustration, the vet is doing a continuous SQ closure from left to right. In order to position the needle, she is twisted around, leaning over, and has a raised elbow.
And here is me doing the same thing.
It wasn’t until I took this video that I realized how awkward this is, and after a little research I realized how easy the solution could be. Just by doing the same closure from right to left, the surgeon can avoid all the twisting and leaning.
The moral is, if you’re doing something really awkward, there is probably another solution that is a lot smoother and easier.
In addition to repetitive motion and awkward position, forceful motions are the other contributor to hand and wrist pain. The most common times when a spay neuter vet has to use force is during suturing and knot tying, and during castration of large male dogs.
Choosing a suture size that is bigger than what you need for a given surgery means that on every throw of every knot, you will be applying more pounds of force to your ligaments and muscles. Over the course of a surgery day, that’s hundreds of times that you’re applying that extra force.
So in addition to being good surgical practice to select appropriate suture size, it’s also good ergonomic practice.
With the big dog neuter, the spay neuter vet can be using a combination of force and awkward posture to exteriorize the testicle.
As you can see in the illustration, the surgeon has to have a firm grasp and may be pulling with a substantial amount of ulnar deviation– so the wrist is canted towards the pinkie finger. This can be challenging for people with discomfort anywhere in the upper quarter of their body, from hand, wrist, and elbow, to shoulder, neck, and upper back.
Some alternatives that decrease this strain could include
- Open castration
- Sharply dissecting the fibrous attachments around vaginal tunic and between tunic and subcutaneous tissue
- Using a hemostat to clamp the cord just proximal to the testis once the spermatic cord is exposed, to provide a more favorable grip for applying traction, rather than grasping the testis itself
So, as you can see, there are some options for avoiding the three biggest combined risks for hand and wrist pain: repetition, force, and awkward posture. Next post, I’ll talk about instruments and needles.