Coccygodynia has been defined as pain in and around the region of the coccyx.
Various etiologies have been described for this coccygodynia. The most common are falls
resulting in direct injury to the sacrococcygeal synchondrosis.The result is an injury or partial dislocation of the sacrococcygeal junction that causes abnormal movement of the coccyx, especially when sitting pressure is applied to this region. Resulting pain can involve the levator ani muscle and the anococcygeal, sacrotuberal, and sacrospinal ligaments, as well as the gluteus maximus muscles. Another common etiology is childbirth.
Up to one third of all cases of coccygodynia are idiopathic in nature.Other less common causes of this condition include piriformis pain, pudendal nerve injury or neuropathic pain secondary to repeated damage to nerves (eg, in bike riders), pilonidal cyst formation, so called Tarlov cysts or meningeal cysts, obesity (due to excess pressure on the coccyx when sitting), and a bursitislike condition that can arise in slim patients who have little buttocks fat padding, allowing the tip of the coccyx to rub against the subcutaneous tissues, causing friction.
Common pathophysiologic pathways for this condition may include the following:
- Partial dislocation of sacrococcygeal synchondrosis that results in abnormal movement of the coccyx when sitting and riding in car
- Joint being repeatedly forced out of its normal position, causing repetitive trauma (stretching) of the surrounding ligaments and muscles attached to the coccyx and resulting in inflammation of these tissues with pain and soreness when sitting or with straining
- Healing of this condition prevented by continued movement, resulting in further damage and perpetuation of the cycle
Medical Therapy :
Treatment for coccydynia generally falls into either conservative management or surgical intervention categories.Typically, conservative management begins with the use of a nonsteroidal anti-inflammatory drug to reduce inflammation and pain coupled with a donut-shaped pillow or a gel cushion to decrease coccygeal pressure and local irritation. Many physicians also advise the patient to use hot sitz-type baths to further soothe the irritated coccygeal soft tissues.Khan et al have reported on the use of dextrose after nonresponding steroid treatment.
If this therapy fails, usually after a minimum of 2 months, most authors consider injection of corticosteroid or a physiotherapeutically applied (ultrasound phonophoresis or iontophoresis) topical corticosteroid and analgesic combination. Wray et al found that 60% of patients responded to local anesthetics and corticosteroids.
Other proposed treatments are acupuncture reflex therapy. A cryoanalgesia probe inserted percutaneously through the sacral hiatus into the sacral canal to produce anesthesia at the lower sacral nerve roots has been used. This seems to work best when used multiple times with prolonged freezing.Fluoroscopically guided intradiscal injections of a “caine”-like anesthetic plus a corticosteroid seemed to work well for those coccyges that were found to be hypermobile or prone to luxation.
If traditional injection therapies fail, Holubec et al described a neurolytic technique in which lidocaine is injected at the junction of the sacrum and coccyx just in front of the junction. This is directed at the fourth and fifth sacral nerves and the coccygeal nerve. If this provides good pain relief, then a radiofrequency thermocoagulation probe can be inserted at the same site and used to ablate these nerves.
In general, prolonged conservative treatment is usually successful in treating this condition. For those that have persistent coccygeal pain that does not respond to the various treatments outlined above or is not controlled with them, surgery may be an option.
Intraoperative Details :
It involves a midline incision of approximately 4-5 cm made directly over the coccyx. This is an area usually devoid of any muscle tissue. A careful subperiosteal dissection is made, with care being taken to avoid violating the rectum, and the coccyx is freed from the soft tissue and any sacral attachments.
Coccygectomy complications include infection if the rectal vault is violated. If the surgical plane of dissection strays from the subperiosteal region around the coccyx, the rectum may inadvertently be entered. Various authors have also described both local wound problems and deep wound problems, especially scarring, with this procedure. Scar tissue can lead to “nociceptors” around the coccyx to continue to be irritated, causing continued pain and discomfort.