J Manipulative Physiol Ther. 2011 (Feb); 34 (2): 131-137 ~ FULL TEXT
Hong Yu, MD, Shuxun Hou, MD, Wenwen Wu, MD, Xiaohua He, MD
Department of Orthopedics,
The 1st Affiliated Hospital of the General Military Hospital,
OBJECTIVE: This study presents the outcomes of patients with idiopathic degenerative and posttraumatic atlantoaxial osteoarthritis who were treated with upper cervical manipulation in combination with mobilization device therapy.
CLINICAL FEATURES: A retrospective case review of 10 patients who were diagnosed with either degenerative or posttraumatic atlantoaxial arthritis based on histories, clinical symptoms, physical examination, and radiographic presentations was conducted at a multidisciplinary integrated clinic that used both chiropractic and orthopedic services. All 10 patients selected for this series were treated with a combination of upper cervical manipulation and mechanical mobilization device therapy. Outcome measures were collected at baseline and at the end of the treatment period. Assessments were measured using patients' self-report of pain using a numeric pain scale (NPS), physical examination, and radiologic changes. Average premanipulative NPS was 8.6 (range, 7-10), which was improved to a mean NPS of 2.6 (range, 0-7) at posttreatment follow-up. Mean rotation of C1-C2 at the end of treatment was improved from 28° (±3.1) to 52° (±4.5). Restoration of joint space was observed in 6 patients. Overall clinical improvement was described as "good" or "excellent" in about 80% of patients. Clinical improvements in pain and range of motion were seen in 80% and 90% of patients, respectively.
CONCLUSIONS: Chiropractic management of atlantoaxial osteoarthritis yielded favorable outcomes for these 10 patients.
From the Full-Text Article:
To the best of our knowledge, this is the first report to review the outcomes of cervical manipulation combined with the supplementary therapy on the management of neck pain due to atlantoaxial osteoarthritis. The pathology of degenerative changes of the atlantoaxial osteoarthritis is believed to be similar to that of other common osteoarthritis affecting the lumbar and subaxial cervical spine,  such as the development of degenerative fibrosis. However, degenerative fibrosis arising from the atlantoaxial facet joint is less well recognized than other common osteoarthritis. Because of their uncommon presentation, degenerative fibrosis of atlantoaxial osteoarthritis can be confused with other pathologic entities, including rheumatoid fibrosis, tumors, and migrated disc herniation. A CT scan can be used to rule out the above pathologic entities and assess the anatomical details of C1/C2 before the treatment.
Currently, 2 types of treatment options are clinically used to manage atlantoaxial osteoarthritis: operative and nonoperative managements. Kuklo et al  suggested nonoperative management as the first option as long as it was effective and the symptoms were tolerable. Surgical treatment such as atlantoaxial arthrodesis is only indicated when pain is intractable after conservative treatment.  Although most patients obtain pain relief after surgery, a significant percentage of patients developed late complications because of the surgery and required revision surgery.  Existing literature about nonoperative management is sparse. There was a report of the intraarticular C1/C2 blocks that were suggested to be helpful in delineating pain.  Rehabilitation using cervical traction and immobilization with a collar was also reported.  One study also reported the use of oriental alternative herbal medicine.  However, no chiropractic management was ever been reported.
Literature review revealed that although both operative and nonoperative managements could relieve pain in some degree, both managements might not be effective enough to achieve long-term sustained improvement and eliminate the complications. For example, cervical traction and immobilization are nonspecific treatments that may relieve pain temporally; reoccurrence of symptoms were often seen after a period. Intraarticular cortisol injection may reduce inflammation and may lead to pain relief; however, this therapy often induces more joint degenerative changes such as joint adhesion. Most surgical procedures involve C1/C2 joint fixation and sacrifice joint mobility. Late complications can cause worse pain and require revision surgery. In contrast, spinal manipulative therapy differs greatly from the aforementioned nonoperative and operative treatments. Spinal manipulation has been shown to mobilize z joints and increase z joint space,  which not only relieves the pain caused by joint degeneration but also restores joint mobility and lessens the degenerative process.
Because of the advantages of spinal manipulation, we applied HVLA spinal adjustment in treating patients with atlantoaxial osteoarthritis in our clinic. High-velocity, low-amplitude spinal adjustment could precisely mobilize the C1/C2 joint; yet, it would maintain the integrity of adjacent soft tissues. Our results documented pain improvement on the NPS, overall clinical improvement, and radiographic improvement in most of patients after a period of C1/C2 joint manipulation supplemented by the mobilization device.
To accomplish maximal benefit of spinal manipulative treatment, we also applied mobilization with a device as a supplementary treatment. Instrument-assisted manipulation has been shown effectively to increase the ROM in a variety of cases.  The device was used to mobilize the surrounding soft tissues and ease muscle spasm; the goal was to further reinforce the effect of upper cervical adjustment on the treatment of atlantoaxial osteoarthritis.
It is noticed in this case series that restoration of the atlantoaxial joint space after manipulation in follow-up radiographs was associated with symptomatic improvement in some patients. This evidence suggests that spinal manipulation combined with instrument-assisted therapy may have a positive impact on the degenerative process of atlantoaxial osteoarthritis.
Finally, the existence of posttraumatic atlantoaxial osteoarthritis may be controversial because most of the existing literature about atlantoaxial osteoarthritis relates to idiopathic degenerative atlantoaxial osteoarthritis. Nonetheless, posttraumatic atlantoaxial osteoarthritis usually occurs in younger patients. A careful history may reveal the history of neck or head injuries. The symptoms and radiographic presentations are similar to those of idiopathic degenerative atlantoaxial osteoarthritis such as neck pain, reduction of ROM, and narrowing C1-C2 joint space. We also noticed that posttraumatic patients often responded well to the manipulative therapy. These patients required relatively shorter duration of therapy and had better prognosis when compared to patients with idiopathic degenerative atlantoaxial osteoarthritis.
A limitation of this study was that it is a retrospective case review, and there were only a small number of patients; therefore, no major conclusions can necessarily be applied to other patients. In addition, the patients were selected based upon their findings; thus, there is likely some bias in patient selection for this study. The wide range of ages and inclusion of both idiopathic and posttraumatic degenerative atlantoaxial osteoarthritic cases may have also led to variability in the change of NPS scores. Another limitation includes the interpretation of radiographic reevaluation. Although great efforts were made to keep the patients' position consistent in all radiographic evaluations, we could not rule out the possibility of a small difference in radiographic positioning from one time to another, which may have influences joint space measurement. The current study did not consider the style or quality of HVLA cervical spinal manipulation delivered to the patients. Future prospective studies and clinical trials to determine if chiropractic management of atlantoaxial osteoarthritis is beneficial are warranted.
This case series suggests that some of the signs and symptoms of atlantoaxial facet osteoarthritis, which can occur in the elderly because of degenerative disorder and younger patients because of trauma, may be improved by upper cervical spinal manipulation combined with mobilization with a mechanical device.