Manipulation under anesthesia
Manipulation under anesthesia or fibrosis release procedures is a multidisciplinary, chronic pain-related manual therapy modality which is used for the purpose of improving articular and soft tissue movement. This is accomplished by way of a combination of controlled joint mobilization/manipulation and myofascial release techniques. Medication-assisted manipulation may also be used to describe the procedure, although that term more broadly categorizes the varied forms of existing MUA techniques. In any form, MUA is used by osteopathic/orthopedic physicians and specially trained chiropractors. It is intended as a means of breaking up adhesions of or about spinal joints, or extremity joint articulations to which painfully restricted range of motion significantly limits function. Failed attempts at other standard conservative treatment methods, over a sufficient time-frame, is one of the principal patient qualifiers.
Procedure
In the outpatient ambulatory or hospital-based setting, with a qualified medical physician in attendance, the anesthetic or medication component/s of the spinal MUA procedure may be provided in one of two ways.Intravenous (IV) infusion (administered by an anesthesiologist)
Historically, the medical literature identifies sodium pentothal as the earliest of the anesthetizing agents used with the MUA procedure. That was followed by a period during which propofol was used to induce a “twilight state”. The latter became the doctor-preferred means of rendering the service, as it offered preservation of patient responsiveness during the delivery of treatment. With today’s MUA procedure, deep conscious sedation is accomplished with agents such as propofol, through monitored anesthesia care.Local injection (administered by an anesthesiologist or pain management physician)
As a less common mode of MUA treatment, select injectable medications can be administered directly to affected synovial joints, spinal facet joints or into the surrounding epidural space. Local anesthetic injection allows previously incomplete office-based manual therapy methods to be better delivered/tolerated, but outside of the general anesthesia scenario. When rendered to the spine, this variety of MUA procedure is qualified by terms such as manipulation under joint anesthesia and manipulation under epidural anesthesia.History
Medication Assisted Manipulation has been used since the 1930s, and MUA was practiced by osteopathic physicians and orthopedic surgeons in the 1940s and 1950s. It was largely abandoned due to complications from general anesthesia and due to the type of nonspecific manipulation procedures used. It was modified and revived in the 1990s, primarily by chiropractors, and also by osteopathic physicians; this was likely due to safer anesthesia used for conscious sedation, along with increased interest in spinal manipulation.In the MUA literature, spinal manipulation under anesthesia has been described as a controversial procedure. It has had a history susceptible to enthusiastic claims of success and indiscriminate use. With continued misperceptions about the findings and significance of primary research, similar issues remain today. An example of this is seen in endorsements for MUA that inaccurately cite study outcomes and/or focus on selective information which places the procedure, and the practice of multiple day applications, in a more favorable light. The table that follows provides detail concerning this phenomenon.
Some historical misperceptions about the findings of spinal MUA research
| Author/s cited | Commonly reported outcomes claims | Actual outcomes data and relevant study methods, as reported by publication |
| Bradford and Siehl | 71% of 723 MUA patients had good results and 25.3% had fair results | Overall, for 723 cases, 60% had good results, 30% had fair results, and 10% had poor results. Most patients received a single procedure dose. As for the 185 patients with herniated disc, 26.4% had good results and 44.3% had fair results, with the author reporting, “improvement was quite temporary in a number of cases, since 51% required subsequent operation.” |
| Chrisman, et al. | 51% of patients reported good to excellent results three years post MUA | 51% of 39 patients had good or excellent results after rotatory manipulation of the spine under anesthesia. Of patients with positive myelograms, 37% had good to excellent results three years or more after manipulation. All patients received a single procedure dose. |
| Krumhansl and Nowacek | Of 171 patients receiving MUA, 25% had no pain, 50% were much improved, and 20% were better and could tolerate their pain | Of 171 patients, most of whom received a single procedure dose, approximately 25% were “cured”, 50% were “much improved” and 20% were “better, but”. |
| Kuo and Loh | 83% of 517 patients treated with MUA responded well | Of 517 patients receiving manipulation, 76.8% had satisfactory results. However, the number of patients anesthetized during manipulation is not reported. In general terms, the authors state, “Prior to manipulation, general anesthesia with intravenous thiopental sodium may be given to suppress pain and muscle spasm.” Seventy-three patients had a condition recurrence or relapse, ranging from 2 months to 12 years after the first series of manipulations. Unresponsive patients underwent surgical exploration and received a second series of manipulations after revision of the treatment protocol such that 434 of 517 patients are reported as having responded well to manipulation. |
| Mensor | 83% of 600 patients with EMG-verified radiculopathies reported significant improvement following MUA | For over 600 patients treated, a cursory evaluation led the author to “believe that the percentage of success or failure has not changed materially” from the original report. The original report cited excellent to good results in 64% of private patients and 45% of industrial accident patients with disabilities. Overall, 83% of patients received a single procedure dose, with the author reporting, “repeated manipulation is not justified” for satisfactory results. Within neither paper is EMG testing mentioned as part of the patient’s objective findings or as a qualifier for treatment. |
| Ongley, et al. | Patients that had back pain for a minimum of 10 years reported an 87% recovery rate after MUA | Eighty one patients had an average pain duration of 10 years. Patients in the experimental group were placed in a diazepam-induced amnesic state, and received manipulation after administration of local anesthetic to six different ligaments of the lumbar, lumbopelvic, and sacroiliac regions. At six months, of the 40 patients in the experimental group who received a single procedure dose, 87.5% had greater than 50% improvement in disability scores and 37.5% had recovered completely. |
State of evidence
Spinal MUA
Since the 1930s, spinal manipulation under anesthesia has been reported in the published medical literature. Within the existing base of studies are some reports of positive results. However, it appears that as part of the evolution of the procedure, the medical literature reveals many variations in the type of sedatives/medications used, manipulation technique, the number of MUA sessions employed, the span of time between procedure doses, and the types and breadth of application of post-MUA adjunctive and/or rehabilitative measures.There has been and remains a strong theoretical basis for spinal MUA. However, considering the aforementioned differences in existing published studies, field practitioners have not had an objective and uniform means by which to establish evidence-based treatment protocols. Also, because the preponderance of studies are of lower level evidence the issue of long-term effectiveness of MUA in the management of specific spinal conditions has yet to be investigated. Another area for which basic experimental research is lacking to support the efficacy of MUA treatment of the low back, and other spinal regions, relates to the two presiding theories that flexibility of the spine may be increased when adhesions are reduced, and MUA is more effective at treating adhesions than office-based manual therapy methods. Perhaps of greater significance, the circumstances by which or how often spinal adhesions may form in the general population, in the presence or absence of prior surgery or vertebral fracture, have not been addressed in the medical literature. To date, after tens of thousands of spinal MUA procedures having been performed in the United States, and with more than eight decades worth of related studies, there is only one published paper in the MUA literature that clearly demonstrates the presence of spinal adhesions. That relates to two patients, whose pre-MUA advanced diagnostic imaging revealed fibrosis after prior lumbar surgery.
A 2005 consensus statement from the American Academy of Osteopathy indicates that research and publication is limited for the use and effectiveness of MUA. More recently, it has been reported that there are gaps in the medical literature for spinal MUA in the areas of patient selection and treatment protocols. On account of that, a Delphi process was undertaken to develop evidence-informed and consensus-based guidelines for the chiropractic profession. The outcome of that process offers direction to MUA practitioners and facilities, although not intended for individual patients.
Notably, the criteria recommended by members of the chiropractic profession are distinctly different from the criteria established by the American Academy of Osteopathy. Moreover, the Delphi method is a consensus process which represents consenting opinion from an impaneled group of experts. But with expert opinion serving as the lowest level of evidence in the medical evidence hierarchy, the MUA-related Delphi process publication of 2014 does not enhance the state of the evidence for spinal MUA. Therefore, the largely anecdotal basis for procedural effectiveness, and continued reliance upon the spinal MUA protocols historically used, are what principally influence the practice of MUA today.
In comparison to other available treatment options for chronic spine pain patients, it is the benchmark of the randomized controlled trial that could best define patient candidacy, optimal procedure dosing, and long-term effectiveness for MUA. Previous MUA investigators have mentioned the use of inconsistent protocols and have called for large-scale MUA studies for chronic low back pain. To date, no such studies have been undertaken.
Due to the lack of high-level research evidence for the long-term clinical efficacy of spinal MUA, several traditional criteria for patient selection are without support or remain unproven. The most recent analysis of the published medical evidence for MUA shows that disc herniation/protrusion qualifies as at least a relative contraindication, with risk for injury and no proven long-term benefit. Also, in the presence of a positive lumbar EMG study with lumbar disc herniation, Level II evidence suggests that patients will eventually need surgical correction. For chronic neck and low back pain patients who also have significant anxiety/stress, Level II evidence suggests that MUA will not be of therapeutic benefit. Accordingly, most insurance carriers in the United States maintain medical policy which deems the spinal MUA unproven or experimental/investigational.
Extremity joint MUA
Patients that may qualify for MUA to an extremity joint include those with stiff post-operative knee joints that have undergone total knee replacement. Range of motion data taken at discharge following TKA have been suggested as an indicator for MUA, when falling short of the “optimal zone” of ≥70˚ flexion combined with an extension deficit of ≤10˚. It appears that the ideal period for applying manipulation to knee stiffness after TKA is at less than 20 weeks from primary surgery, with no added benefit reported from re-manipulations. Similarly, another recent study also found that MUA is useful for decreased range of motion but the success rate of repeated MUA was less than that of the primary dose.Outside of the above clinical scenario and related research, the supportive evidence for MUA to other extremity joints is weak, inconclusive or non-existent. The shoulder, when failing to achieve flexibility following standard treatment, is one of the extremity regions for which the frozen shoulder condition has traditionally been cited as an indication for MUA. There are some supportive studies in this area, including one showing that patients fare better with intervention at 6 and 9 months after condition onset. However, for those studies which represent the highest level of research evidence, the results of two recent systematic reviews for frozen shoulder raise question as to treatment superiority when compared to other forms of treatment. Namely, in the 2012 systematic review, Maund, et al. found a single adequate study, but no evidence there of better outcome with MUA versus home exercise. In the 2015 systematic review, Uppal, et al. determined MUA to be equivocal at best, when compared to hydrodilation and steroid injection.
The provision of MUA to an extremity joint is reserved for primary conditions thereof, such as a frozen articulation. The practice of applying MUA to an extremity joint that conjoins the spine, as a routine component or an extension of a spinal MUA procedure, is not supported by clinical investigation.