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Demystifying the Treatment of Strain/Sprain Injuries of the Lower Back, Part 2

Part 1

Examination and Treatment of Low Back Pain

To properly diagnose and treat a low back syndrome, a detailed history, a thorough examination, and an understanding of the pain-sensitive structures and postural and phasic muscles in the lumbopelvic region are necessary.


Taking a detailed history is one of the most important aspect of an examination. The practitioner has to find the various clues from the patient’s history and then piece together the exact cause(s) of the patient’s low back pain. Some of the following questions are good to ask the patient: What was the date of onset of your low back pain? Was there a particular incident which caused your low back pain? Did you have a sudden onset of low back pain, or did the pain come on gradually? What exacerbates your low back pain complaints? Is this the first time you have suffered from low back pain?

The examiner should ask about past surgeries, accidents, serious illnesses or blood in the urine. Affirmative answers to these questions may be red flags of possible tumors, infections or visceral disorders, and warrant a referral to a primary doctor.


As patients walk into the examining room, their gait should be carefully evaluated during the stance and swing phase for muscular imbalances. Do they have a toe in or toe out gait? This may reveal possible medial or lateral hamstring tightness. Do they have a gluteus medius gait? Patients with this type of gait will tilt the entire torso over the midstance femur and will reveal weakness of the gluteus medius musculature. Do they have a gluteus maximus gait? This type of gait will reveal weakness of the gluteus maximus musculature in which the patient’s entire torso will hyperextend over the pelvis during early stance phase.10

Do these patients have a decreased stride length? This may reveal tightness of the hamstrings and hip flexor musculature. Do they have an antalgic lean or favor one leg over the other? When the patients are in the static position, the practitioner should observe for a sway back or lordotic posture. The sway back patient will have a flat lower back with an increase in the posterior curve of the thoracic and thoracolumbar region. Patients will usually complain of pain in the thoracolumbar junction. This posture develops as a result of weak hip flexors and lower abdominal musculature. Patients with a lordotic posture will have an increase in the anterior curve of the low back, caused by tightness of the psoas and erector spinae musculature and weakness of the abdominal and gluteus maximus musculature. Patients with a lordotic posture will usually complain of pain across the low back.

Muscle Testing and Orthopedic Tests

Contract-relax-antagonist-contract stretching of the hamstrings, quadriceps, hip flexors, external rotators and abductor musculature bilaterally is not only effective in treating low back pain, but is also an effective tool in revealing the various muscular imbalances which may be the cause of the pain. Muscle testing hip extension may reveal improper firing sequences as a result of weakness of the gluteus maximus musculature. Double leg raising and lowering and trunk curl sit-ups are useful in evaluating psoas and abdominal musculature strength.

Patients with weak abdominals when lying supine with their legs extended and raised 90 degrees will prematurely arch their back when lowering their legs to the ground. Wilson’s test is useful for revealing tightness in the rectus femoris, psoas and tensor fascia latae musculature. Some of the other useful orthopedic tests are Ober’s test; Trendelenberg’s test; sit-and-reach test; Nachlas’ test; Ely’s test; Valsalva’s test; Kemp’s test; and straight leg raising test. Lower extremity deep tendon reflexes and motor and sensory tests of the lower extremities should be conducted. If Valsalva’s test, Kemp’s test and straight leg raising test continue to test positive, and the patient’s complaints of radicular symptoms in their lower extremities continue, then a referral to a neurologist or an orthopedic surgeon for an evaluation would be warranted.


Keys to Treating Low Back Strain/Sprain Injuries

1. Control pain.

2. Increase flexibility of the lumbopelvic musculature.

3. Increase strength of the lumbopelvic musculature.

4. Body must be trained to do certain motions.

5. Decrease emotional stress/depression.

In my treatment protocol, #1-4 will be addressed. Feldenkrais and Thomas Hannah relaxation techniques would be useful for #5 if necessary. Both of these doctors explain how emotional stress can cause voluntary reactions to become involuntary. This can lead to sustained contracture of the erector spinae musculature. The goal is to become aware of this and train your body to regain voluntary control of these reflexes, thereby relaxing the low-back musculature.11

There are three phases of healing: acute phase (1-2 days); repairative phase (2 days – 6 weeks); and a remodeling phase. As soon as the patient with a strain/sprain low-back injury can tolerate range-of-motion exercises, acute therapy should commence to promote a more efficient healing process during the reparative phase.

A recent book on repetitive motion disorders published by the American Academy of Orthopaedic Surgeons cites a histologic study in which Nirschl proposed that overuse syndromes are not an inflammatory process but instead represent failed repair of disrupted connective tissue. Supporting this theory were biopsy samples from tendons of patients with epicondylitis that showed disorganized collagen; pale, haphazardly arranged mesenchymal cells; an excessive amount of matrix tissue; and vascular buds with an incomplete lumen and insufficient elastin. This disorganized mesenchymal tissue has poor potential for healing. Based on these observations, a reasonable goal for healing would be to stimulate an inflammatory mediated process with appropriately oriented fibroblasts (laying down parallel fibers in the tendons, which would increase their strength) and to reduce the amount of matrix tissue through the use of appropriate exercises.12

Mooney states that active release techniques (ART* soft-tissue management system) “is a promising new deep-tissue technique for treating cumulative trauma disorders.”12 A practitioner skilled in this technique can palpate fibrotic lesions in the injured tissues. A fibrotic lesion will predispose this region to hypoxia, ischemia, and will result in a trigger point region with improperly oriented fibroblast fibers. To effectively treat this lesion, the practitioner will trap the lesion, and the patient will take the tissue from its shortened to elongated position. The goals for using this technique are to break up the lesions to allow the muscle to regain its proper length and strength, and to decrease painful symptoms.13When the muscle is properly treated and soft tissue motion is restored, the next goal for treatment is to free up joint motion. Manipulation will be used to free up joint fixations in the lumbar and sacroiliac region.

It has been demonstrated that meniscoids are present in the zygapophysial joints of the spine and contain innervation by C fibers. It seems reasonable that they might become entrapped between the opposing joint surfaces, and gapping of the joint might release the entrapped meniscoid, resulting in enhanced function. More recently, it has been postulated that stress on the capsule of the involved joint alters the afferent nerve traffic from the type I mechanoreceptors so that central control of motion cannot determine the joint’s spatial relationship. This alteration in neural control is postulated to affect the length and tone of the segmentally related muscles, further restricting normal joint movement.6

A high-velocity, low-amplitude thrust technique will cause a 1/8″ gapping at the joint and will free up joint motion. ART and manipulative procedures are very effective treatment tools which free up soft tissue and joint restrictions in the low-back region.

Teaching patients with low back pain a daily effective stretching routine that they can conduct at home will speed up the process of healing and will also prove useful in the prevention of low-back pain after treatment is ended. Using a flex-band 15-20 minutes per day to stretch the hip flexors (see Figures 1.1A and 1.1B), hamstrings (see Figures 1.2A and 1.2B), external hip rotators and abductors (see Figure 1.3), adductors (see Figure 1.4), erector spinae musculature (see Figure 1.5) and quadriceps (see Figure 1.6) will enhance the recovery process.

Figure 1.1A
Figure 1.1B
Figure 1.2A
Figure 1.2B
Figure 1.3
Figure 1.4
Figure 1.5
Figure 1.6

I find a high compliance rate with flex bands, mainly because of their convenience. They allow you to do more range-of-motion exercises. Exercise balls tend to have a low compliance rate.They are effective tools, but they are too inconvenient and difficult to store at home.

Strength training for the lumbopelvic region should also commence with emphasis placed on strengthening the abdominal musculature, gluteus maximus musculature and quadricep musculature.

Combo therapy is a modality which may prove beneficial in speeding up the healing process of a low back strain/sprain injury. Combination therapy is an effective modality in which the electric muscle stimulation machine is connected to the ultrasound machine, allowing one to direct electric muscle stimulation and ultrasound through the ultrasound head. Ultrasound therapy in a continuous mode is effective for heating localized areas of deeply placed tissues. The effect of heat at a therapeutic level may induce muscle relaxation. Vasodilation also has a direct effect on removal of metabolites, which further decrease muscle excitability and allow relaxation. Electrical muscle stimulation may be used to maintain or gain range of motion and to break down or stretch adhesions. Indirectly, it may also influence pain, particularly when the pain is secondary to muscle spasm.14


Having an understanding of the anatomical and physiological structures of the low back and combining that with a strong biomechanical knowledge of the mechanisms which can cause low back pain are essential for a proper diagnosis of this condition. However, even though one has an understanding of the structures in the low back, the diagnosis can be confusing because of multilevel innervation and the instances where several conditions contribute to the low back syndrome.

Manipulation and ART are two effective tools in freeing up soft tissue and joint restrictions. In this author’s opinion and clinical experience, a low back strain/sprain injury can be appropriately treated when combining ART, a flexibility program utilizing flex bands, and a proper strengthening routine.


(includes references from parts I and II)

  1. British Medical Journal April 26, 1997;314:7089, p. 1225.
  2. Fordyce W. Nursing Homes. International Publishing Group, 1996, p. 32.
  3. Cailliet R. Low Back Pain Syndrome, 4th edition. Philadelphia: Davis Company, 1988, pp. 22-24, 76-103.
  4. Cramer G, Darby S. Basic and Clinical Anatomy of the Spine, Spinal Cord, and ANS. Mosby-Year Book, Inc., 1995, pp. 205-217, 251-271, 355-370.
  5. Greenman P. Principles of Manual Medicine, second edition. Baltimore: Williams & Wilkins, 1996, pp. 146-147, 449-456.
  6. Lewit K. Manipulate Therapy in Rehabilitation of the Locomotor System, second edition. Butterworth-Heinemann Ltd., 1991, pp. 14-32, 126.
  7. Kendall F, McCreary E, Provance P. Muscle Testing and Function. Baltimore: Williams & Wilkins, 1993, pp. 133-176, 350-354.
  8. Janda V. Muscle strength in relation to muscle length, pain and muscle imbalance. In: Harms-Rindahl K (ed.) Muscle Strength. New York: Churchill Livingstone, 1993.
  9. Robbins. Robbins’ Pathologic Basis of Disease, fourth edition. Philadelphia: W.B. Saunders Company, 1989.
  10. Michaud T. Foot Orthoses and Other Forms of Conservative Foot Care, Newton, MA, 1997, p. 181-191.
  11. Hanna T. Somatics. Addison-Wesley Publishing Company, Massachusetts, 1988, p. 42-95.
  12. Mooney V. The Journal of Musculoskeletal Medicine 1998, p. 11-18.
  13. Leahy M. Improved treatments for carpal tunnel. Chiro Sports Med 1995; Williams & Wilkins, p. 6-9.
  14. Reid DC. Sports Injury Assessment and Rehabilitation. New York: Churchill Livingstone Inc., 1992, p. 31-64.

Additional information was gathered from the following sources:

  • Liebenson C. Rehabilitation of the Spine. Baltimore: Williams & Wilkins, 1996.

Part 1

Demystifying the Treatment of Strain/Sprain Injuries of the Lower Back, Part I

Part 2

Joshua Dubin,DC,CCSP


A majority of the American population has suffered from low-back pain at some point in their adult lives. Prolonged rest used to be the mode of treatment for lumbar strain/sprain injuries, but this form of treatment leads to atrophy of the lumbopelvic musculature and ongoing low back dysfunction. This author’s goals of treatment for a low back strain/sprain injury are to control pain, restore soft tissue and joint function, and prescribe a good strength training and flexibility program for the lumbopelvic region.

The focus of this paper will be to describe the perception of low back pain; explain the postural and phasic muscles of the low back; detail the biomechanics of the lumbar spine and pelvis when bending forward and returning to the neutral standing position; depict four distinct situations which can predispose an individual to low back pain; and then explain this author’s examination protocol and treatment plan for low back strain/sprain injuries.

Key words: low back pain, rehabilitation, Flex Band ®, chiropractic, lumbar, A.R.T.


Low back pain is common in the general population, affecting more than 60 percent of people at some time in their lives and often causing appreciable disability.1 According to an article in a 1992 issue of Business and Health, the average per employee nonspecific back pain disability costs among 12 diverse businesses were $1,000 in direct costs, $800 in hidden costs (lost productivity, temporary replacement hiring, bookkeeping, etc.), and $400 in disability costs for a total of $2,200 per employee.2

This paper will discuss four distinct situations which predispose one to low back pain; normal stress on an unprepared normal low back; normal stress on a deconditioned normal low back; sudden excessive stress on a normal low back; and normal stress on an abnormal low back. A rational strategy for the prevention and treatment of low back pain will be presented.3

Perception of Pain

Nociceptors are receptors located near the skeletal muscles, ligaments, tendons, joints, and fascia of the low back region. An anatomic structure must be supplied by nociceptive nerve endings to be a cause of low back pain. There are four main sources of neural innervation to spinal structures: the ventral rami; the dorsal rami; the recurrent meningeal nerve; and the gray rami communicants of the sympathetic trunk. All of these nerves innervate structures which can be possible low back pain generators (see Table I).

Tissue damage causes a release of prostoglandins, histamine, bradykinin, potassium and serotonin, which stimulate and activate nociceptor nerve endings. Activated free nerve endings release substance P into the surrounding area, leading to the release of histamine from adjacent tissue cells. Group IV afferent fibers relay nociception through the dorsal root ganglion and transport neurotransmitters, substance P and calcitonin, to the dorsal horn of the spinal cord, where they synapse and release these excitatory neurotransmitters. Nociceptive information then travels from the dorsal horn of the spinal cord via the neospinothalamic or paleospinalthalamic ascending tracts to the thalamus. From the thalamus this information then travels to the cerebral cortex where pain is perceived.4 Ongoing pain will lead to faulty motion patterns which will result in cumulative trauma injuries to adjacent muscle structures.

Table 1: Possible Pain Generators in the Low Back

Ventral RamisPsoas musculature
Quadratus lumborum musculature
Intertransverse musculature
Dorsal Ramis

Multifidus, rotators, semispinalis
Zygapophyseal joints
Periosteum of posterior vertebral arch
Interspinous, supraspinous and intertransverse ligaments, ligamentum flavum
Erector spinae muscles

Recurrent Meningeal Nerve

Periosteum of posterior aspect vertebral body
Posterior aspect of disc
Posterior longitudinal ligament
Anterior aspect spinal dura mater

Gray Ramis Communicants Associated with the Sympathetic Trunk

Periosteum of anterior and lateral aspect vertebral body
Lateral aspect disc
Anterior aspect disc
Anterior longitudinal ligament

Phasic and Postural Muscles of the Lower Back

To effectively treat and understand the cause of low back pain, it is necessary to be familiar with the phasic and postural muscles surrounding the spine and adjacent structures. The phasic and postural muscles in the lumbopelvic region are listed in Table II.

Slow©twitch muscle uses oxidative metabolism and has a high capillary density, giving it its characteristic red color. The twitch speed is slow, and the function of these muscles is that described as being tonic or postural. Muscles that have high density slow-twitch fibers react to functional disturbance by shortening and tightening. Fast-twitch fibers use a glycolytic metabolic pathway, fatigue rapidly and have low capillary density that results in a white color. Muscles of this type are described as phasic in function and react to disturbance by weakening.5

Table II: Phasic & Postural Muscles in the Lumbopelvic Region

Phasic1. Abdominal oblique, transverse abdominal & rectus abdominal musculature
2. Gluteus maximus & medius musculature
3. Quadricep musculature

1. Iliopsoas musculature
2. Erector spinae musculature
3. Rectus femoral musculature
4. Quadratus lumborum musculature
5. Multifidus, rotators, semispinalis musculature
6. Hamstrings
7. Piriformis musculature
8. Iliotibial band & tensafascialata musculature

Precipitants of Low Back Pain

The first situation which can lead to low back pain is normal stress on an unprepared normal low back. This individual attempts to lift an object and underestimates or is unaware of the actual weight of the object. As a result, the lower back muscles are not prepared to protect the functional unit. A functional unit consists of two lumbar vertebrae, an adjoining disc, facet articulations, surrounding ligaments, muscles, fascia, and the nerve roots exiting at that level. Initially, the surrounding musculature contracts to protect the functional unit; however, when the applied force exceeds the maximum strength of the musculoligamentous unit, one gets a strain/sprain injury to the lower back.

The second situation which can lead to low back pain is normal stress on a deconditioned normal low back. A low back can be structurally normal, but not necessarily conditioned. Conditioned, or functionally normal, means the surrounding low back tissues have appropriate flexibility and strength to accomplish a particular movement without injury. A conditioned normal low back will be able to bend forward and return to the standing position with ease. However, a deconditioned low back is susceptible to a strain/sprain injury when put under ordinary stress. These two coupled motions of bending forward and returning to the standing position are dependent on the strength and flexibility of various muscle groups and will be discussed as movement 1 and movement 2 respectively.

Movement 1: Anterior Flexion of the Lower Back

The low back consists of five functional units. There is approximately 9 degrees of flexion allowed at each functional unit, allowing up to 45 degrees forward flexion. At 45 degrees the fascia, muscles and ligaments of the low back are taut and no more flexion is allowed without forward rotation of the pelvis. An endpoint of motion in forward flexion of the low back is that point at which a person bends forward and can go no farther (no pain). If the ligaments, fascia and muscles of the low back are not flexible, this endpoint of motion will be decreased and will result in a strain/sprain injury of the low back when attempting to bend forward to 45 degrees. In order to bend forward past 45 degrees, the pelvis has to rotate anteriorly. The anterior motion of the pelvis is dependent on the flexibility of the hamstrings and gluteus maximus musculature. If the hamstrings and gluteus maximus musculature are not flexible, the pelvis will be limited in anterior flexion. When this limited endpoint of forward flexion is exceeded, one will usually complain/suffer from an acute onset of low back pain.

Movement 2: Extension of Lower Back from Full Anterior Flexion to Normal Posture

When individuals are bent over in forward flexion, they should initially flex their knees to return to the neutral standing position. Flexing the knees will tense the quadricep musculature, which tenses the iliotibial band, which tenses the tensor fascia latae musculature and pretenses the gluteus maximus musculature. The gluteus maximus contracts and the pelvis derotates from its anteriorly rotated position. At the same time, the abdominal oblique and transverse abdominal musculature contract. This action tightens the fascia surrounding the erector spinae musculature and takes pressure off of the low back when returning to the upright position. The kinetic motion chain of movement 1 and movement 2 clearly indicate that weak abdominal musculature (abdominal obliques & transverse abdominals), weak gluteus musculature, weak quadricep musculature, tight erector spinae musculature and tight hamstrings are precursors to lower back injury.6

Having flexibility of the iliopsoas muscle (hip flexor) is also crucial in the prevention of low back pain. Contracture of the psoas muscle will inhibit the gluteus maximus musculature, thereby limiting derotation of the pelvis when returning to the neutral standing position, which will predispose the low back to injury. The psoas musculature originates from the lumbar transverse processes and inserts onto the lesser trochanter of the femur making this muscle a powerful hip flexor. However, if the psoas musculature is not conditioned properly and shortens from its its normal length, it will cause an individual to have a lordotic posture. A lordotic posture in a standing neutral position consists of an anteriorly rotated pelvis with an increased anterior curve of the lumbar spine. Usually an individual with a lordotic posture will have a protruding abdomen, especially if the abdominal musculature is weak. This lordotic posture will put undue stress on the erector spinae musculature and will lead to a repetitive motion injury to the lower back. An individual with a lordotic posture will complain of a gradual onset of low back pain which will increase with time if not treated appropriately.

An individual without a lordotic posture can also suffer from a repetitive strain to the lower back. Prolonged standing or sitting in a forward flexed position causes a repetitive strain to the erector spinae musculature, posterior longitudinal ligament, supraspinous ligaments, and fascia of the low back. This forward flexed posture also causes the nucleus pulposus to migrate posteriorly which may cause failure of the outer annular fibers of the disc. Mackenzie techniques are based on doing extension exercises to strengthen the erector spinae musculature of the lower back and preventing injury due to a repetitive or constant anterior flexion posture.3 It is important to strengthen the erector spinae musculature to a certain extent; however, it depends on the individual’s low back condition on whether this form of treatment is warranted. Florence Kendall states that:

People who have a lordosis often complain of having a “weak back.” The term is used because of the feeling of aching and fatigue in the low back, and because of the inability to lift heavy objects without pain. This type of back is mechanically weak and inefficient because of the faulty alignment, but low back muscles are not weak. The connotation of the word “weak” is that the back muscles are weak and in need of strengthening exercises. On the contrary: the muscles are strong, overdeveloped and short, and back extension exercises are contraindicated.7

In this author’s opinion, a good strengthening and flexibility program for all of the muscles surrounding the lumbopelvic region with more emphasis on flexibility training for postural muscles and strengthening exercises for phasic muscles should be implemented in a treatment plan for all low back pain patients. One must also be aware of the interrelationship of antagonistic muscles in the lumbopelvic region. A tight postural muscle will make it difficult to strengthen an antagonistic phasic muscle as indicated by Table III.6Electromyographic (EMG) data show that a tight erector spinae muscle will be active during its reverse action, trunk flexion, and thus inhibits the action of the agonist and the abdominals. After the erector spinae muscle has been stretched, not only does it relax during trunk flexion, but also a significant, spontaneous facilitation effect is seen in the abdominal muscles.8 An individual with weak abdominal musculature and tight erector spinae musculature would want to begin a daily erector spinae stretching routine, not only to stretch the low back musculature, but also to allow for proper strengthening of the abdominal musculature.

Table III: Antagonistic Postural and Phasic Musculature in the Lumbopelvic Region

Postural Musculature   Phasic Musculature
Tight psoas
Weak gluteus maximus
Tight erector spinae musculature
Weak abdominal musculature
Tight tensafascialata/quadratus lumborum
Weak gluteus medius musculature

The third condition which can lead to low back pain is a sudden excessive stress on a normal low back, such as a severe blow to the low back while playing a contact sport; auto accident; traumatic fall; or other acute traumas. Trauma-related injuries can cause a severe strain of the musculature surrounding the low back and can also extensively involve the ligaments, fascia, disc and nerve roots in this region. As a result, these injuries will take longer to heal than low back strain/sprain injuries not related to trauma.

The fourth condition which can lead to low back pain is a normal stress on an abnormal low back. An abnormal low back does not have integrity of the functional units and is, therefore, susceptible to low back pain under normal stress. Table IV lists several tumor and tumor-like processes, joint diseases and muscular disorders which decrease the strength of the functional unit and predispose these individuals to low back pain under normal conditions.9

Table IV: Abnormal Low Back Conditions

Tumor & Tumor-like Processes Muscular Disorders Joint Diseases
Metastatic carcinoma Muscular dystrophy Ankylosing spondylitis
Multiple myeloma (limb-girdle) Reiter’s syndrome
Osteosarcoma Myasthenia gravis Tuberculosis arthritis
Ewing’s sarcoma   Suppurative arthritis
Hodgkins lymphoma   Osteoarthritis
Osteoid osteoma   Osteoporosis

Editor’s note: Part II of “Demistifying the Treatment of Strain/Sprain Injuries of the Lower Back” will appear in the February 22nd issue of Dynamic Chiropractic.


  1. British Medical Journal April 26, 1997;314:7089, p. 1225.
  2. Fordyce W. Nursing Homes. International Publishing Group, 1996, p. 32.
  3. Cailliet R. Low Back Pain Syndrome, 4th edition. Philadelphia: Davis Company, 1988, p. 22-24, 76-103.
  4. Cramer G, Darby S. Basic and Clinical Anatomy of the Spine, Spinal Cord, and ANS. Mosby-Year Book Inc., 1995, p. 205-217, 251-271, 355-370.
  5. Greenman P. Principles of Manual Medicine, 2nd edition. Baltimore: Williams & Wilkins, 1996, p. 146-147, 449-456.
  6. Lewit K. Manipulate Therapy in Rehabilitation of the Locomotor System, 2nd edition. Butterworth-Heinemann Ltd., 1991, p. 14-32, 126.
  7. Kendall F, McCreary E, Provance P. Muscle Testing and Function. Baltimore: Williams & Wilkins, 1993, p. 133-176, 350-354.
  8. Janda V. Muscle strength in relation to muscle length, pain and muscle imbalance. In: Harms-Rindahl K (ed.) Muscle Strength. New York: Churchill Livingstone, 1993.
  9. Robbins. Robbins’ Pathologic Basis of Disease, 4th edition. Philadelphia: W.B. Saunders Company, 1989.

Part 2

Anterior Cruciate Ligament Injury: Pre- and Post-operative Rehabilitation

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acl_1The anterior cruciate ligament (ACL) is a tough fibrous structure that attaches the tibia (lower leg bone) to the femur (thigh bone) (Figure 1). This ligament helps to stabilize the knee by preventing excessive forward movement of the tibia on the femur. ACL injuries commonly occur in athletes participating in sports such as football, basketball, soccer, and volleyball, where movements such as cutting, pivoting, single leg landing and rapid decelerations are routinely performed. Tearing of the ACL is most commonly caused by landing awkwardly or cutting on a fully extended or slightly flexed leg with the foot turned outward (Figure 2).

Skiers usually injure the ACL when they catch the inside edge of a ski on ice, causing them to lose control and fall backwards as they hyperflex the knee. The injured athlete may report hearing a “pop” and that it felt like the knee was being stretched apart. Examination of the knee may reveal extensive swelling around the knee joint, loss of full extension of the knee and an inability of the athlete to bear weight on the injured leg. Manual testing may reveal excessive forward movement of the tibia on the femur.

acl_2Once the athlete is diagnosed with an ACL injury, the first step is to decide whether to undergo surgery to reconstruct the torn ligament, or to rehabilitate the knee without surgery. ACL reconstructive surgery would be recommended for athletes who continue to suffer from repetitive bouts of the knee giving away, or for those athletes who want to return to a highly competitive sport level. Athletes deciding not to have reconstructive surgery may be able to return to an active lifestyle after completing a rehabilitation program; however, they must learn to modify their activities to accommodate for the compromised stability of the knee due to the lost check-rein function of the ACL.

Pre-operative rehabilitation is important for those athletes who choose to undergo surgical reconstruction. The main goals of the pre-operative rehabilitation protocol are to reduce swelling around the knee joint, and to restore full range of motion and functional strength to the injured limb. The pre-operative rehabilitation phase prepares the patient physically and mentally for both the surgery and the postoperative rehabilitation program.

Post-operative rehabilitation begins immediately after surgery. The most important goals in the first two weeks are to reduce swelling and restore full range of motion of the knee in extension and flexion. Once range of motion is restored and swelling is minimized, the progression of the post-operative program depends on the patient’s determination, level of swelling and pain, and the clinician’s knowledge of the normal biological progression of healing of the reconstructed ligament. Some athletes progress rapidly in the post-operative phase of rehabilitation and may begin sport-specific training at a low intensity level in two to three months. However, full functional rehabilitation of the reconstructed ACL may not occur until six to 12 months post-operatively. The therapist must be careful on the progression of the rehabilitation exercises and on the timetable for returning the athlete to their particular sport. An accelerated rehabilitation program under a controlled environment allows the athlete to return to sport sooner, without increasing the risk of complications.

Origin and Insertion Points of the Anterior Cruciate Ligament

The bottom of the femur consists of the medial and lateral femoral condyles, circular bony protuberances that are separated by an intercondylar notch. The top of the tibia consists of the medial and lateral tibial plateaus, flat slightly concave surfaces that articulate with the respective femoral condyles. The anterior cruciate ligament originates from the posterior outer aspect of the intercondylar notch and proceeds anteriorly, where it inserts onto the outside edge of the medial tibial plateau (see Figure 1).


Graft Tissue Healing Post-Surgery

In athletes, a torn anterior cruciate ligament is typically removed and replaced by their own tissue that is similar in length and strength. The two most common self-tissue grafts are the bone-tendon-bone (specifically, tibial tuberosity bone – patella tendon – patella bone graft) (Figure 3A), and the hamstring tendon graft (specifically, the tendons of the inside hamstring muscle [semitendinosis], and adjacent groin muscle [gracillis]) (Figure 3B). The selected graft tissue would be surgically placed in the anatomical location of the previous ACL and then secured by interference screws.

Both types of grafts have advantages and disadvantages. The surgeon selects the appropriate type of surgery based on the patient’s sport and the movements most frequently used.

A study by Rodeo et al evaluated tendon-to-bone healing in a dog model and found that a firm attachment of tendon to bone occurred at 12 weeks post-surgery. At two weeks post surgery there was still no continuity between the graft tendon and the insertion point in the bone. At four weeks there was minimal continuity between tendon and bone. At eight weeks there was considerably improved continuity between tendon and bone. After 12 weeks the tendon graft was safely secured to the surrounding bone, at which point failure of the graft-insertion point was minimal.

Based on the results of the above study, from zero to four weeks post-surgery therapy should focus on decreasing inflammation and restoring full range of motion of the knee. Swimming, stationary cycling, isometric contraction exercises, and other low-force muscle integrating techniques can be implemented in the earlier stages of rehabilitation. If the patient experiences pain, swelling or decreased range of motion of the knee, the inflammation should be reduced, range of motion restored, and the intensity of the rehabilitation phase should be slowed down. During the 12-week healing period, exercise selection should be carefully monitored by a skilled therapist to reduce the risk of complications.

Rehabilitation of the Knee: Decrease Swelling and Restore Range of Motion

Rehabilitation after ACL reconstruction surgery should initially focus on decreasing inflammation and restoring normal range of motion. Every patient heals differently; the progression of the rehabilitation program should be customized to the athlete and progressed to their tolerance.

Initially decreasing inflammation around the knee joint using ice, compression, and elevation is feasible with a couple of icepacks, an ace bandage, and pillows to prop the leg up. Ice therapy should be maintained 20 minutes on and one hour off, multiple times per day. Ankle pumps (flexion and extention of the foot) with the leg elevated can be conducted five minutes per hour to further reduce swelling. A Cryo-Cuff, if available, is a more advanced method of decreasing inflammation. The Cryo-Cuff can be wrapped around the knee and filled with ice water. A cooler of ice water is attached by tubing to the CryoCuff and can be used to replace the old water in the cuff with ice cold water every hour. Anti-inflammatory medication is also useful in reducing swelling around the knee joint.

The next couple of steps of the post-operative phase should be conducted to the patient’s tolerance.

The patient should use crutches following the first two days post-surgery, with minimal weight bearing. Additional weight may be applied to the injured leg, with crutches, as tolerated. By the end of the first week, the patient may ambulate without the support of crutches if a normal walking gait cycle with full weight bearing can be sustained with no noticeable instability. The patient should be able to ambulate without crutches six to seven days post-operatively.

Restoring full range of motion of the injured knee, particularly in extension, should be a priority in the first two weeks post-surgery. After the first week of post-operative rehabilitation, the patient should be able to fully extend the leg and flex the leg to 110 degrees. At this point, full extension is the most important goal; flexion of the knee improves steadily as swelling around the knee joint decreases. If full extension of the knee is not restored within two weeks post-surgery, scar tissue may develop in the joint, preventing the restoration of full knee extension.

The continuous passive motion machine (CPM), an electrical motor-driven device, may be used in the hospital immediately following recovery from surgery. This machine has shown promise in helping to restore normal motion and flexibility of the injured leg. The CPM supports the leg while moving it from full extension to a progressively set degree of flexion. There is a ten-second pause at the end of each movement, during which time the patient will isometrically contract the quadriceps (front thigh muscles).


After the patient is released from the hospital, a specific series of exercises (provided by a trained therapist) should be done as often as possible to restore full range of motion of the knee in extension. Passive extensions (Figure 4A) and weighted extensions and prone leg hangs (Figure 4B) are useful exercises for restoring extension of the knee. During passive extensions, the patient can lie on the back with the heel propped up on pillows. Once the leg is relaxed in extension, the patient can periodically contract the quadricep musculature to push the knee further into extension. The patient then holds the quadracep contraction for five seconds, then returns to relaxed extension. This exercise should be done for 15 minutes and repeated every waking hour. If extension is not achieved this way, the patient may progress to weighted extension exercises by placing a five to ten pound weight just above the knee and following a similar procedure as passive extensions. The patient should be instructed to perform this exercise for ten minutes, taking the weight off for one minute and repeating multiple times during the day. Prone leg hangs (Figure 4B) can also aid in restoring extension of the knee. Have the patient lie on the stomach with the knee just past the edge of the table or bench with the knee in full extension; use a weight if struggling with full extension. The patient should perform this exercise for ten minutes, by gently flexing and extending the knee and repeating multiple times per day.

Towel stretch extension exercises (Figure 4C) can be incorporated if the above exercises are not restoring extension appropriately. The patient sits on a bench, places a towel around the foot of the injured leg, and applies tension to the towel to dorsiflex the foot, pulling the toes backward. The patient then raises the heel off of the ground to bring the knee into extension while placing the other hand on the thigh to stabilize the leg.

The patient would lie down on the back with the ankle raised and secured into a heel rest; a pad would be placed above and below the knee joint. These pads are secured by ropes passing through a ratchet system that would be tightened to force the knee into full extension (Figure 4D).

A normal gait cycle depends on a person’s ability to lock the knee in full extension while weight bearing. The following resistive tubing exercise can aid in accomplishing this goal. Resistive tubing can be secured above the standing patient’s knee cap and anchored to a bench behind the patient; the resistive force of the tubing will promote full extension while standing.


Heel slides, supine leg hangs, and prone flexion exercises with the Flexband® (Figures 5A, 5B, and 5C) can be used to restore flexion of the injured knee. Heel slides are conducted with the patient lying on the back, sliding the heel towards the buttocks until tension is felt; the position is then held for one to two minutes. Then the heel slides down into full extension. This exercise should be repeated ten times, once every waking hour. See Figure 5A.

Supine leg hangs are conducted with the patient lying on the back, grasping the hands behind the thigh and lifting the thigh towards the chest with the leg flexed. The patient then allows the leg to drop down into flexion, holding this position for two minutes. The knee is then returned to a relaxed extended position and repeated multiple times throughout the day. See Figure 5B.

Prone (on the stomach) flexion exercises can be conducted with the Flexband®. Starting out on the back, the patient creates a toe-loop with the Flexband® around the injured knee’s foot and then turns onto the stomach. The band is then swung over the head, slowly increasing the band’s tension, hand over hand, while the ankle is aligned to the buttocks. The stretch should be held for three to four minutes, repeated several times throughout the day. See Figure 5C.

Rehabilitation of the Knee: Restoring Static Restraints, Dynamic Restraints, Proprioception and Sport-Specific Skills

The static restraints of the knee are the ligaments and bony architecture that limit movement. Surgical reconstruction of the ACL restores the check-rein function of the ligament by preventing excessive forward movement of the tibia on the femur.

The dynamic restraints of the knee are the muscles and tendons that surround the knee. These muscles and tendons maintain joint position and react to changing loads and forces. Post-surgery rehabilitation depends on restoring the function of these dynamic restraints, with the main focus on restoring flexibility and strength to the hamstring and quadriceps musculature. During the initial phases of rehabilitation, isometric strength training exercises are implemented, where the muscle neither shortens nor elongates, but force is generated. A straight leg raise is an example of an isometric strength training exercise for the quadriceps musculature. Later in the post-operative rehabilitation phase, exercises will be conducted to develop eccentric strength (whereby the muscle elongates to decelerate a particular movement) and concentric strength (whereby the muscle shortens to promote a particular movement). An example of an eccentric exercise would be step-downs off of a two-inch box with the good leg. During a step-down the quadriceps of the injured leg will eccentrically fire to decelerate and control leg flexion; simultaneously the gluteus musculature of the injured leg would fire to stabilize the pelvis so the body doesn’t tilt to the side of the uninjured leg that is stepping down. An example of a concentric strengthening exercise would be forward stepups, whereby the quadriceps would concentrically contract to force the leg to extend. Rehabilitation of the dynamic restraints will aid in taking stress off of the repaired ACL, preventing re-injury.

Proprioception is best defined as reception of sensory input from mechanoreceptors (specialized cells located in the skin, muscles, tendons, ligaments, and joints), the visual field, and the vestibular system. This sensory input is processed at the spinal cord, then at the mid-brain or the more complex cerebral region. Then a reflex or motor response is generated and then regulated until the desired movement is attained. There are three main types of reflexes, the fastest being the involuntary knee jerk reflex that involves no brain processing or thought. The second fastest reflex involves thought processing through the midbrain, and the slowest reflex involves more involved thought processing in the cerebrum. Repetitive balance and movement drills can transfer reflexes that initially involve complex sensory processing in the cerebrum to the mid-brain, leading to faster more precise movement patterns. Proprioception training involves retraining and fine tuning reflexes and movement patterns through balance drills, agility drills, plyometric jumping drills, and sportspecific training. Proprioception training will increase the state of readiness of the knee joint, decreasing the chance of re-injuring the ACL upon return to sport.

Full functional rehabilitation of the knee depends on restoring static stability, dynamic stability, and proprioception. The rehabilitation program should be individualized in regards to the patient’s coordination, desire, and specific sport.

Weeks 0-2

The goals of the first two weeks of post-operational rehabilitation are to reduce swelling, restore full range of motion in extension and flexion, ambulate without the use of crutches, and sit down and stand from a seated position. Straight leg raises, side raises/abduction exercises, and assisted leg extensions to full extension (with the help of the therapist or the opposite foot) are good exercises to initiate muscle firing of the quadriceps and gluteus musculature.

Muscles located in and above the back of the thigh, the hamstrings and gluteus structures, stabilize the pelvis during ambulation and squatting-type movements. Two exercises that are instrumental in returning coordinated strength to the leg are isometric co-contractions of the hamstring and quadriceps musculature, and the other is properly performed quarter squats and full chair squats. The co-contractions should initially be conducted at 30 degrees of flexion, progressing at ten-degree intervals up to 90 degrees. Squats should be conducted at the patient’s tolerable range of motion in a controlled manner. During the squat, the patient should focus on squeezing the hamstrings and gluteus musculature during the downward movement of the squat and keep a vertical shin angle; these two actions will prevent the patient from leaning forward and placing undue stress on the knee joint. As the patient squats down, the quadriceps musculature fires to decelerate flexion of the leg, while the hamstring and gluteus musculature fire to decelerate the pelvis from rotating forward. The hamstring musculature also aids the reconstructed ACL in its check-rein function on the tibia. These exercises are crucial in developing the coordinated muscular activity of the hamstring, gluteus and quadriceps musculature that is necessary for a normal walking gait during full weight-bearing on a flat surface, as well as walking up and down stairs and getting into a seated position.

Step-downs (Figure 6A) are another useful exercise that can be included in the second week of post-operational rehabilitation. For this exercise, the patient stands with both legs on a designated raised surface and then steps down to the ground with the non-injured leg. These exercises should be conducted in front of a mirror to ensure proper technique. Apprehension in flexing the injured leg or weakness in the gluteus musculature on the same side will cause the patient’s pelvis to drop down to the side of the leg that is stepping down. Correct technique of step-downs is necessary for the patient to maintain hip stabilization, prevent pelvis drop, and proper cocontraction of the hamstring and quadriceps musculature of the injured leg to achieve a controlled leg flexion as the other foot touches the ground surface. Step-downs should commence at two inches off the ground for 25 controlled repetitions. The step-down height can be increased to four, six, and eventually eight inches as the patient regains motor control of the hip stabilizers, gluteus and hamstring musculature, as well as the decelerator of leg flexion, the quadriceps musculature.

acl_6aAccording to Bill Knowles, director of iSPORT at the Vermont Orthopaedic Clinic in Rutland, Vermont, after ACL repair, the sutures are usually removed between ten days and two weeks post surgery. Once the wound is healed, pool therapy can begin. Bill Knowles recommends specialized pool routines for “total body training with an emphasis on hip and knee flexion and extension movements, as well as core strength exercises to include all of the muscles involved in stabilizing the torso from the hips to the shoulder.” The patient holds floatation bars while conducting various movements in the pool to improve the coordinated strength of the hip stabilizers, knee extensors and flexors, as well as the core strength musculature.

After 115 degrees of leg flexion is attained, stationary cycling can commence to increase range of motion of the knee joint, as well as provide light endurance exercise. Other exercises that be used to increase range of motion and muscle coordination are swimming and the elliptical machine.

All of the above exercises included in the second week of the post-operative rehabilitation phase should be conducted to the patient’s tolerance and in a controlled setting. If swelling occurs or if there is decreased range of motion in the knee joint, the progression of the rehabilitation phase should be slowed down, the range of motion restored, and the swelling reduced.

Weeks 3-5

acl_6bIn weeks 3-5, functional exercises can be added to the rehabilitation routine. The following exercises are recommended:

  1. Balance star drills on a flat surface – balance while reaching forward with the good leg or opposite arm.
  2. Bulgarian squats – with the good leg up on a bench/chair, perform the squat with the injured leg (Figure 6B).
  3. Pelvic bridge lying on the back, legs flexed to 90 degrees, lift the buttocks off of the floor while squeezing the glutes and the hamstrings.
  4. Balance drills on a disco-sit/curved seat cushion.
  5. Ball squats without weights, and later with weights held by the patient during the squat (Figure 6C).
  6. Single leg Romanian deadlifts – on a step box, bend forward from the trunk while holding a weighted ball with both hands in front, and balance on the deconditioned leg (Figure 6D).
  7. Leg Presses – single leg.
  8. Abduction, adduction, single leg extensions, calf raises.
  9. Ball tosses while balancing on a balance board.
  10. Lunges.
  11. Exercise ball hamsting curls.
  12. Towel stretches and standing extension stretches with resistive tubing.

Delayed onset muscle soreness is expected. If there is normal range of motion, no immediate swelling, and muscle pain dissipates in two to three days, the patient can continue to progress with the rehabilitation routine. acl_6c_d

Weeks 6-8

  1. Progress to heavier weights with the above exercises.
  2. Continue towel stretches and Flexband® stretches to maintain and increase range of motion of the knee in both flexion and extension.
  3. Proprioception drills, e.g. wobble board exercises balancing on two legs, balancing on one leg, ball tosses while balancing, done with the eyes closed for advanced drills.

Weeks 8-11

Romanian deadlifts.

Light sport-specific training, e.g. a basketball player shooting free throws or conducting passing drills.

Week 12

If the patient has full range of motion and strength of the musculature surrounding the knee, he or she may start a running program: Treadmill running for ten to 15 minutes, level surface running on cement for 2030 minutes, hill running, sprinting, figure 8’s, side sliding, start and stop shuttle runs, and 45-degree cutting. Jumping drills can teach the athlete how to land softly while sitting back and incorporating the hamstring and gluteus musculature. These agility drills can be progressed as tolerated.

4-6 Months

The patient can return to full light sport participation if assuming full range of motion, 90 percent strength of the hamstrings and quadriceps musculature (as compared to the healthy leg) and success in conducting all of the agility drills with no pain or swelling.

The therapist should explain to the patient that while it is okay to return to full light sport specific training, it can take up to three months of participation in their sport to regain the complex movement patterns of the particular sport. It may take up to seven months to a year for “ligamentization” of the grafted tissue, whereby the grafted tissue becomes almost identical, in its properties, to the original anterior cruciate ligament.

Post Surgical Treatment of the Anterior Cruciate Ligament at Dr. Dubin’s office

Treatment of the repaired ACL at this office would commence after the sutures are removed and the wound is healed, approximately two weeks post-surgery. Treatment would consist of:

  • Specific muscle work, including active release technique, to free up soft tissue motion of the surrounding knee musculature, helping to restore normal range of motion of the knee in flexion and extension;
  • Ultrasound and electric muscle stimulation combo therapy to break up scar tissue and restore normal muscle tone;
  • Patella mobilization techniques.

The above treatment protocols would aid in breaking up scar tissue and restoring proper joint and soft tissue range of motion.

Good communication and repeat follow-ups among the physician and therapists are crucial in creating and maintaining the optimum treatment protocol for pre- and postsurgery rehabilitation of the anterior cruciate ligament, allowing for a safer and quicker return of the athlete to their particular sport.


This paper was made possible with the help and expertise of Keith Callanan MPT, CSCS, of Elite Physical Therapy (781-297-0979) and Bill Knowles ATC, CSCS, Director of iSPORT (802-422-6191). I recommend their services to all patients who are suffering from anterior cruciate ligament injuries.

If you have any questions or want to set up an appointment with Dr. Dubin please call 617-471-2444.


1) Shelbourne DK, Rowdon GA: Anterior Cruciate Ligament Injury. The Complete Athlete, Sports Med 17(2) 132-140, 1994.

2) Rodeo SA, Arnoczky SP, Torzilli PA, Hidaka C, Warren R: Tendon-healing in a bone tunnel. J Bone Joint Surg 75A: 1795-1803, 1993.

3) O’Neill, Daniel F. , New Hampshire Knee Center, The 1st Week Post-Op 2003

4) Rinsberg MA, Mork M, Jenssen HK, Holm I: Design and Implementation of a Neuromuscular Training Program Following Anterior Cruciate Ligament Reconstruction. J of Othopaedic and Sports Physical Therapy 2001; 31 (11): 620-631.

5) Hewett TE, Paterno MV, Myer GD: Strategies for Enhancing Proprioception and Neuromuscular Control of the Knee. Clinical Orthopaedics and Related Research 2002; number 402: 76-94.

6) Bill Knowles ATC, CSCS, director of iSPORT at the Vermont Orthopaedic Clinic, Rutland, Vt.

7) Keith Callanan, MPT. Owner of Elite Sports. Inc. Stoughton, Ma.

8) Amiel D, Kleiner JB, Roux RD, Harwood FL, Akeson WH: The Phenomenon of “Ligamentization”: Anterior Cruciate Ligament Reconstuction with Autogenous Patellar Tendon. J of Orthopaedic Research 1986; (4): 162-172.

Additional references

Reid D: Sport Injury Assessment and Rehabilitation. 1992.

Norman, SW: The Knee. 1994.

Tennis Elbow/Lateral Elbow Pain

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tennis1Repetitive strain injuries, or overuse injuries of tendons and muscles, are very common and are both treatable and preventable. The severity of these injuries is directly related to the number of repetitions of a particular activity and the technique utilized while performing that activity. The severity is also proportional to the strength of the muscles utilized as compared to the force of the activity. The “weekend warrior” who attempts to participate in a sport without any prior training is a good candidate for predisposition to repetitive strain injuries. His or her technique in performing the sport would probably be poor, and the muscles utilized would not be conditioned to deal with the repetitive force of the activity. This kind of overuse causes small tears in the muscles and tendons. If tissue injury occurs faster than tissue repair, pain and eventually weakness would be experienced in the region of the damaged tissues.

Tennis elbow is a repetitive strain injury to the extensor muscles and tendons of the forearm. The symptoms of tennis elbow are of pain on the outside of the elbow and back of the forearm, and weakness with grip. A one-handed backhand performed with poor technique is a common cause of tennis elbow (Fig. 1). The one-handed backhand places a lot of strain on the muscles and tendons of the forearm that have a common attachment to the outside of the elbow, called the lateral epicondyle. Initially, pain on the outside of the elbow and back of the forearm will occur when playing tennis. If the injury is not treated appropriately, the symptoms will become more severe and constant, eventually limiting the activity. Repetitive use of a hammer or screwdriver or carrying a heavy briefcase are other potential causes of “tennis elbow.”

Case Study

Birgitte came to Dr. Dubin’s office for care with complaints of pain on the outside of her right elbow that traveled down the back of her forearm. Birgitte stated that she’d recently come back from a trip to Denmark, where she drove a stick shift for approximately 1000 miles. Later, for business, she carried a heavy briefcase with her right arm fully extended by her side. She then played tennis with her daughter’s racket, during which time she noticed an extreme pain on the outside of her right elbow.

Dr. Dubin explained to Birgitte that her activities caused a repetitive strain injury to the forearm musculature, leading to the development of tennis elbow. Using muscle anatomy flashcards, Dr. Dubin showed Birgitte several muscles she may have injured: extensor carpi radialis brevis, extensor carpi radialis longus, extensor carpi ulnaris, extensor digitorum, brachioradialis, anconeus (Fig. 2), and supinator musculature (Fig.3)
Treatment of Birgitte’s tennis elbow condition consisted of specific muscle treatment techniques to free up soft tissue motion of the forearm musculature, chiropractic adjustments to free up joint motion in the wrist and elbow, and ultrasound/electric muscle stimulation combotherapy to decrease pain and restore normal muscle tone. Birgitte was also instructed to ice her elbow 20 minutes on, 1 hour off, and reapply to decrease inflammation.

During Birgitte’s second office visit, she was instructed on a home rehab routine consisting of wrist flexion (Fig. 4A), wrist extension (Fig. 4B), and alternating forearm supination (point the palm down), and pronation (point the palm up) exercises. After three treatment sessions at Dr. Dubin’s office, Birgitte’s tennis elbow condition was almost resolved. Birgitte also began wearing an air splint placed approximately one and a half inches below the elbow to support the extensor musculature of the forearm when playing tennis.


Preventative Measures

  • If you’re a tennis player, take tennis lessons with a pro to address proper stroke technique: two handed backhand instead of a single handed backhand; turn the shoulder and trunk into the swing; and when the racket contacts the ball, the wrist should be slightly extended and deviated upward instead of flexed and deviated downward.
  • Select the proper racket, keeping in mind grip size, racket weight, and string tension.
  • Be sure to properly warm up before play begins.
  • After the match is over, ice the elbow.
  • Wear an air splint placed 2 finger widths below the elbow crease, with the airbag placed over the major extensor muscle bellies. The splint should fit comfortably.
  • Initiate a workout routine emphasizing strength and flexibility training for the forearm, trunk, and shoulder musculature.