Effectiveness of Motor Control Exercises for Persistent LBP

Practitioners often use the term nonspecific low back pain (LBP) when the source of LBP is unknown. Among the factors linked to persistent LBP are the lack of stability and control of the deep trunk muscles, such as the transverse abdominus and multifidus. Motor control exercises have been developed and used by LBP patients with the goal of regaining control and coordination of the spine. The exercises incorporate a retraining of deep trunk muscles that progress from static to dynamic tasks of varying complexity.

Although the use of motor control exercises for patients with persistent LBP has been supported in previous laboratory studies, the effectiveness of such exercise has not been established. In this study, Macedo et al from the University of Sydney, Australia, conducted a systematic review of the literature using a meta-analytical approach.

Studies that met the inclusion criteria (1) conducted a randomized, or quasi-randomized, trial that compared motor control exercises with placebo, no treatment or other active treatment; (2) used motor control or a specific spinal stablilization or core stability exercise protocol; (3) evaluated patients with LBP whose symptoms either persisted >6 weeks or were recurrent; and (4) reported outcome measures related to pain, disability, quality of life (QOL), return to work or recurrence.

The original database search yielded 1052 articles, of which 42 articles were subsequently added. Of these 45 articles, 14 met the inclusion criteria and were then grouped based on 4 treatment protocols. Outcomes for pain, disability and QOL measures were assessed short-term (<3 months), intermediate (3-12 months) and long-term (>12 months after randomization; Table 1).



Conclusion

This systematic review provided evidence that motor control exercises used alone or as a supplement to other therapies may be effective in reducing pain and disability in patients with persistent LBP. It also showed that motor control exercises are not necessarily superior to manual therapies and other forms of exercises for this patient population.

Macedo LG, Maher CG, Latimer J, McAuley JH. Motor control exercise for persistent, nonspecific low back pain: a systematic review. Phys Ther 2009;89: 9-25.

Elastic Resistance Intervention Enhances Balance Responses in Ankle Instability

Lateral ankle sprains are among the most common injuries to the lower limb, with a recurrence rate as high as 70%. Chronic ankle instability (CAI) has been defined by feelings of "giving way," weakness and pain during activities. Sensorimotor and balance deficits have also been linked to CAI.

Along with other therapeutic exercise programs, elastic resistance exercises facilitate progressive weight-bearing overload to the injured joint. This study by Han et al from San Jose State University, California, assessed the effectiveness on balance of elastic tubing intervention alone.

Forty patients (20 patients with CAI consisting of >1 ankle sprains within the previous year and >ankle sprains within the previous 3 years; 20 healthy individuals) participated Ten participants from each group were randomized either to an exercise group or a control group, resulting in 4 equal groups: CAI exercise, CAI control, healthy exercise and healthy control. The exercise groups performed 4 different elastic tubing exercises:

• front pull
• back pull
• crossover
• reverse crossover

Tubing tension was increased weekly and calibrated as a percentage of the individual's body mass. Participants performed 3 sets of 15 repetitions at each of 3 visits/week for 4 weeks.

The assessed balance measure was the total travel distance (TTD) and reflected the excursion of the center of pressure for a 20-second duration while participants balanced on a force plate using single limb stance. TTD was recorded at baseline, at the end of the 4-week intervention and 4 weeks after completion of the intervention.

TTD balance significantly improved for both exercise groups (p < .001) at the end of the intervention period, compared with the control group. CAI exercise group patients showed greater improvements in balance than those in the CAI control group, while demonstrating a mean change of 8.2 cm, compared with a 2.4-cm change for healthy normals. Members of the CAI exercise group maintained these positive changes at the 4-week follow-up.

Conclusion

The findings of this study suggest that a 4-week intervention of elastic resistance training results in favorable responses in balance when measured using the single limb TTD outcome. The effectiveness of these changes as they relate to the prevention of ankle sprains needs to be the next logical step of study for patients with CAI.

Han K, Ricard MD, Fellingham GW. Effects of a 4 week exercise program on balance using elastic tubing as a perturbation force for individuals with a history of ankle sprains. J Orthop Sports Phys Ther 2009;39:246-255.

Factors Linked to Improvements in Adhesive Capsulitis

Adhesive capsulitis, or "frozen shoulder," is a soft-tissue disorder that results in pain, shoulder joint stiffness and a progressive loss of motion. Women between 40 and 60 years of age are most often affected. Although adhesive capsulitis is self-limiting, disabling symptoms may last an average of 3 years, with health care costs estimated to be between $7,000 and $8,000 per episode.

Non-operative physical therapy interventions for adhesive capsulitis may include therapeutic exercise, manual therapy techniques, electrotherapeutic modalities and thermal modalities. However, little is known about which non surgical interventions increase or decrease the likelihood of a successful outcome.

Jewell et al from Virginia Commonwealth University studied whether physical therapy interventions, either in isolation or combintation, predicted meaningful changes in pain and physical health for patients with a primary diagnosis of adhesive capsulitis.

Data were examined for 2370 patients (mean age, 55 years; 65% women) diagnosed with adhesive capsulitis who received outpatient physical therapy services. Four outcome measures were evaluated

• the Physical Component Summary -12 (PCS-12)
• the physical function (PF) sub-score of the PCS-12
• the bodily pain (BP) subscore of the PCS-12
• a hybrid function (HF) score

A nested logistic regression model identified interventions that predicted clinically meaningful changes in the outcome measures, defined by the authors as an improvement of >50% from baseline scores. Odds ratios described the likelihood of meaningful improvement.

Two intervention categories, "joint mobilization and mobility" and exercise," increased the odd of meaningful improvement in BP and HF, respectively. The odds of a meaningful change in HF scores were 50% greater in patients who received exercise interventions, compared with those who had not received interventions. Two intervention categories "iontophoresis and phonophoresis," and "ultrasound and massage," decreased the likelihood of meaningful clinical improvement in pain and physical health by 19% to 32% in patients with adhesive capsulitis.

Conclusion

This study found that interventions that include joint mobilization and exercise (strengthening, stretching and home programs) effectively improved pain and functional outcomes in patients with adhesive capsulitis. Passive modalities may reduce or delay favorable outcomes because they may not effectively address the most impaired tissues of the shoulder joint. Therefore, interventions that increase joint mobility and exercise should be emphasized.

Jewell DV, Riddle DL, Thacker LR. Interventions associated with an increased or decreased likelihood of pain reduction and improved function in patients with adhesive capsulitis: a retrospective cohort study. Phys Ther 2009;89:419-429.

Non-weight-bearing Exercises Beneficial For Knee OA

Knee osteoarthritis (OA) can be a debilitating disease. Pain, stiffness and loss of proprioception and strength affect mobility and function. Previous studies have shown that high resistance weight-bearing exercises effectively increase strength and proprioception for patients with knee OA; however, the loading demands associated with weight-bearing exercises may aggravate symptoms of OA. Lin et al from National Taiwan University Hospital assessed whether high-resistance exercises performed in non-weight-bearing positions could improve function and proprioception in patients with knee OA.

A total of 108 patients with a history of knee OA >6 months duration and joint changes confirmed by radiographs were randomly assigned to 1 of 3 groups. The proprioception training (PrT) group performed foot-stepping exercises in a sitting position at progressively more challenging speeds and resistance using a computer game that required the patients to use a variety of knee movements in multiple directions. The strength training (ST) group performed concentric and eccentric quadriceps muscle training in a sitting position. Resistance provided through a cabled dynamometer was progressively increased every 2 weeks. Patients in both the PrT and ST groups trained 3 x /week for 8 weeks. Patients in the control group received no interventions.

The effectiveness of these interventions on pain and function was assessed using the Western Ontario and MacMaster Universities (WOMAC) Osteoarthritis Index pain and function sub-scores. Walking speeds over level terrain, stairs and spongy surfaces, as well as knee strength and joint position sense, were evaluated at baseline and after the 8-week intervention.

Following interventions, both PrT and ST groups significantly improved (p < .008) in WOMAC-pain and -function scores; the control group's scores did not change. Consistent with previous research on specificity training, the PrT and ST groups responded differently to the interventions. The PrT group showed greater improvement for walking times on spongy surfaces and improvements in joint position sense. Not surprisingly, the ST group had significantly faster times for stair climbing. Although both groups increased their strength, slightly greater improvements were found in the ST group after training (Figure 1).

Conclusion

This study demonstrated that non-weight-bearing exercises may be an effective intervention to improve function in knee OA patients who may not be able to tolerate weight-bearing exercises. Exercises that targeted proprioception resulted in improvement during stair-climbing activities. A combined program that focuses on both types of training should be considered to optimize functional outcomes in patients with knee OA.

Lin D-H, Lin C-H J, Lin Y-F, Jan M-H. Efficacy of 2 non-weight-bearing interventions, proprioception training versus strength training, for patients with knee osteoarthritis: a randomized clinical trial. J Orthop Sports Phys Ther 2009;39:450-457.

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