When a surgery is minimally invasive, many people - especially those who experience a great deal of pain relief - may think that physical therapy is unnecessary. It is very important that muscle function is at its best after any spine procedure in order to maximize recovery and to minimize potential future problems.
- Usually back pain is associated with at least some level of physical deconditioning. People may realize they have weak muscles but may not understand its negative impact on spine and joint function.
- And even for those individuals who are in good physical condition, the evidence shows localized weakness still occurs in the segments with the disc problem.1 Furthermore, it has been shown this weakness will not necessarily get better once the disc problem has been treated.2 Therefore, in order to protect patients from having a vulnerable localized weakness, spine specific training is generally recommended after any spine procedure.3
- In addition, to maximize return of function for all patients, retraining with education on posture, body mechanics and back protection is critical.4,5,6,7
This article addresses the specific physical therapy needs to maximize short and long term results of minimally invasive spine procedures, which can lessen likelihood of recurrence.8,9,10,11 A typical example of a minimally invasive spine surgery is a microdiscectomy for a symptomatic herniated disc.
In the case of the patients who may still have residual pain and other symptoms following minimally invasive spine procedures, a variety of pain control strategies can be used. Many spine therapists can help by identifying motions and positions that alleviate pain.
Manual therapy can help resolve motion or soft tissue restrictions. Modalities such as ice or electrical stimulation may be used to help with pain control. Also, educating the patient on how to avoid postures that stress the spine is key.
Poor posture can create unfavorable mechanics in the spine, which can make individuals more susceptible to injury or degeneration.12,6 Posture education can teach patients about disc protection that can be associated with good spine alignment.
"Flat back" syndrome may occur following spine procedures and often indicates a failure of the back extensors to function fully. Flat back is probably less likely to occur with minimally invasive spine procedures since fewer muscles are invaded. But it still could occur as a result of the atrophy associated with the disc pathology.
Patients also may adopt a "sway back" posture showing generalized trunk weakness.6,13 Significant leg length difference, significant right/left differences in pelvic alignment or scoliotic posture may be addressed by either compensating or correcting with muscular training in some cases.14,5
Strengthening: Targeting the Deep Trunk Muscles that Support the Spine
This type of physical therapy, called segmental stabilization of the spine, focuses on addressing localized weakness in the deeper trunk muscles, which can protect individual segments of the spine. Minimally invasive spine procedures will typically spare most or all of these muscles so patients can recover maximal function.3 The techniques for segmental stabilization is supported by many therapists as an essential part of spine programs, especially when disc pathology has been involved, such as a herniated disc or degenerative disc disease.3
The two muscle groups that fire first to stabilize the spine are multifidus and tranversus abdominus. Studies have shown delayed contraction of these muscles in patients with lumbar pain.15,3 There is evidence multifidus atrophies at the level of a disc herniation.1 Most importantly, the recovery of this muscle function must be specifically retrained as it does not occur automatically when the disc pathology is resolved.2
Many large muscle groups allow people to function in daily activities without activating spine stabilizers much, if at all. This lack of muscular support in the spine may in part account for the frequency of degenerative disease seen in the population.
Training of the multifidus and transverses abdominus requires concentration on the part of the patient. Biofeedback devices such as surface EMG or pressure sensing devices can be very helpful. Transversus abdominus is recruited by drawing the abdomen in, creating a pressure toward the back of lumbar spine. Patients may be instructed to do the same movement they would do as if trying to button jeans that are too small.
The patient also can learn to practice the motion lying on their back, creating a downward pressure with the lumbar spine, increasing the reading on a partially inflated blood pressure cuff or other pressure sensing device (Figure 1). Once they are able to do this, they would try to maintain the same pressure while doing various arm and leg movements, training the muscles to maintain spinal stability during those movements.
They also can lie face down and practice the same function by lessening the pressure on the device; i.e. pulling the abdomen away from the cuff (Figure 2). Again, once they can perform this motion, limb movements can be added to create more challenge.4,3
The goal of this training is to provide enough practice and repetition so the function of these muscles is automatic and will start to occur during all other activities and exercise.5,16,6
Strength training with resistance exercises
After spine stabilization training has begun, adding strength training with resistance exercises is helpful for functional movement.17,18 Specific strength training studies have shown resolution of some spine pathologies with conservative (nonsurgical) care.18
It is recommended the patient has spine stabilization capabilities and symptoms under control before increasing this.5 Strength training may be done earlier using "decompression" strength training exercises as shown in Figure 3.
Rebuilding Stamina through Cardiovascular Training
Both lack of strength and endurance have been shown to be related to incidence in low back pain. Deconditioning occurs rapidly in individual's aerobic levels when they become inactive. This often manifests itself as fatigue, which can lead to more inactivity, creating a downward spiral for many patients.
Level of oxygen consumption, or MET level, has been shown to be one of the closest physical predictors of successful outcome of lumbar surgery.19 This makes the patient's home walking program very important. If walking is limited by sensitivity to weight bearing or other joint problems, therapists can help the patient find a feasible alternative (e.g. pool therapy or low impact exercise equipment).
It is helpful to test patient's progress with MET level, which is done most simply by tracking distance with a six or twelve minute walk. Other cardiovascular testing and training procedures are covered, with evidence included in the American College of Sports Medicine manual on testing.20
Regaining Mobility and Flexibility
At times, patients who have leg pain (sciatica) from a herniated disc will have excessive tension along the sciatic nerve down the back of the leg. Overcoming this tension with specific gentle stretching and/or soft tissue mobilization is starting to be recognized as an important rehabilitation component.21
Working on the mobility of various joint areas that a given nerve pathway may cross can be helpful for restoring full excursion of that pathway. For example; with typical sciatica, there is often significant tightness in calf muscles, hamstrings, and hip rotators. The individual joint areas of the ankle, knee, and hip can be worked individually, then added together to minimize tension produced in surrounding structures. The neural structures can have more capability to move with normal function.
Even when a surgery is minimally invasive and has produced immediate pain relief for the patient, a concerted effort at re-conditioning through physical therapy is still an important aspect of the patient's recovery. Improving strength, flexibility, and aerobic conditioning will prevent or at least minimize the chances of any recurrent back or leg pain.