What is a perineal post and why does it matter for your hip arthroscopy?
A Guide to Traction in Hip Arthroscopy
What is Hip Distraction and Why is it Used?
What are the risks of using a perineal post?
What is Hip Distraction and Why is it Used?
During hip arthroscopy surgery a small camera or arthroscope is placed into the joint through small poke holes in the skin. In order to have enough space to work inside the joint the surgeon must apply tension to the limb through traction. Traction on the leg creates just enough space (8-10 mm) for a hip surgeon to perform labral repair, acetabuloplasty or "rim trim", and other hip preserving procedures.
Traditional tables for hip arthroscopy feature a central post which allow for countertraction to be pulled through the opposite leg. This perineal post is well padded to protect the groin but is not without risk, particularly for prolonged procedures.
What are the risks of using a perineal post?
When traction is applied with a traditional post there is compression of the groin against the padded post. Although not common, damage to the labia, perineum, or scrotum can occur.
Pudendal Nerve Pain - The rate of transient (temporary) neuropraxia is between 1.8 and 4.3 percent according to research studies on hip arthroscopy. When this occurs, the patient may experience burning or pain in the clitoris, labia, vagina, penis, scrotum, anus or rectum.
Labia or Scrotal Injury - Superficial skin tears or bruising from friction against the post
Groin Numbness - Neuropraxia to the pudendal nerve can also result in numbness or absence of sensation in the perineal structures. This is temporary but may take weeks to several months to resolve.
Urinary Retention - although rare, urinary retention immediately after surgery has been reported, which may make it difficult to urinate or result in not fully emptying the bladder
How is postless traction done, and why is it better?
Distraction of the hip without use of a central post was developed in the mid 2010s with use of a special table and/or pad designed specifically for this technique. Some high volume hip surgeons have switched to this postless system to reduce risk to the patient and improve their ability to perform surgery safely.
With a postless design, the patient lays on a specialized pad that prevents them from sliding when traction is pulled through the hip. Nothing lays against the perineum and therefore injuries to the genital structures are avoided. This system also allows the surgeon to more easily manipulate and move the leg during surgery, improves visualization with Xray imaging and allows for extremely precise control over the amount of force applied to the leg.
A study at the University of Iowa, where Dr. Scott trained, found switching to postless traction also resulted in patients being able to leave the recovery area and return home faster:
Schaver AL, Mattingly N, Glass NA, Willey MC, Westermann RW. Hip Arthroscopy With and
Without A Perineal Post: A Comparison of Early Postoperative Pain. Arthroscopy. 2021
Sep;37(9):2840-2845. doi: 10.1016/j.arthro.2021.03.045. Epub 2021 Mar 31. PMID: 33812030.
There are many benefits to the postless system and it is worth discussing with your surgeon what type of system they use.