Peroneal Tendon Syndromes Clinical Presentation

The histories for each type of peroneal tendon injury have subtle differences. The key is to have a clinical suspicion and to listen carefully to the patient.

Peroneal tendinitis

Symptoms of pain behind and distal to the lateral malleolus usually occur when the patient returns to activity after time off. Swelling and tenderness may also be present.

Peroneal tendon subluxation

Snapping along the lateral ankle is present, with a sense of weakness or pain. A painful snapping sensation over the lateral ankle is the classic indication of peroneal tendon subluxation.

Pain with toe walking or cutting laterally while playing on a field are also observed.

With acute injury, pain and swelling are noted over the posterolateral aspect of the ankle.

Chronic injuries can lead to subluxation, including recurrent inversion injuries, leading to lateral ankle instability and painful snapping across the ankle.

Peroneal tendon tears

With acute injury, pain and swelling are inferior and posterior to lateral malleolus. The patient may have had pain before the injury, but now the pain is debilitating and strength is decreased. ^[25]

Chronic injury results in the subtle, insidious onset of pain posterior to lateral malleolus that progressively worsens in terms of both function and the level of pain.

Anomalous peroneus brevis muscle injury

This injury can be acute or chronic. The patient may have debilitating pain with the push-off portion of the stance, without a history of ankle injury.

Lateral ankle impingement

This injury is chronic and commonly seen far out from an acute injury, such as a lateral ligament sprain. Many times, the patient will be better for weeks after a sprain, only to have the pain increase with activity without any provocation.

The patient has pain with loading the foot, but it may not always be consistent during the day and week. Pain may be more pronounced after being sedentary or waking up in the morning, but it improves over time.

The location of pain is either posterior to the lateral malleolus along the peroneus tendon or at the anterior talofibular ligament. The latter is typically seen in a patient with a history of ankle sprain. However, the sprain can be remote.

The patient often assumes impingement pain is a sprain that has not yet healed or is due to "weak ankles." The physician must not make that same snap judgment before evaluation. Often, the pain is in the same area as the injury (ATF sprain), but impingement occurs only in small part to the thickening of the ligament. Making the assumption the pain is related to an inability of a ligament to heal can make the true biomechanical reason for the problem difficult to uncover and treat.

The examination should focus on the following 2 areas:

• Ankle function and stability

• Basic core alignment and stability

Ankle

Inspection

Observe the amount and location of any swelling. Note ecchymosis and any ankle or foot deformity (the foot is in varus for acute brevis tears). Note the position of the peroneal tendons, which may be visibly subluxed without manipulative testing. Observe the patient's gait for abnormal rotation, heel strike, or weight transfer.

Palpation

Palpate the lateral ankle ligaments and along the peroneal tendons down to their insertion sites. Palpate along the bony structures to identify possible fractures. Palpate the pulses, and check the neurovascular status.

Specific tests

After testing passive and active plantarflexion, dorsiflexion, inversion, and eversion, a few specific tests for stability should be performed.

Anterior drawer test is performed as follows:

• Have the patient sit on the edge of the table with his or her legs dangling.

• Hold the distal tibia stable with your nondominant hand as the dominant hand pulls the posterior aspect of the calcaneus forward.

• Laxity indicates an injury to the anterior talofibular ligament.

See the image below.

Tilt test is performed as follows:

• With the patient seated on the edge of the table with his or her legs dangling, hold the distal tibia stable with your nondominant hand.

• With the dominant hand holding the calcaneus, attempt to open the lateral ankle compartment.

• Opening indicates an injury to the calcaneofibular ligament.

See the image below.

Peroneal tendon stability test is performed as follows:

• The operator holds the athlete’s foot with one hand, while the opposite hand gently palpates the peroneal tendons just posterior to the lateral malleolus.

• The operator moves the foot into end-range inversion, and then asks the athlete to evert against resistance.

• The other hand is monitoring the peroneal tendon, feeling for a palpable snap, or translation.

See the image below.

Core stability

Standing flexion test is performed as follows:

• The patient stands straight, feet shoulder width apart. The physician sits behind the patient.

• The physician places thumbs on the posterior superior iliac spines (PSISs) bilaterally.

• The patient bends forward to end range of motion, while the physician's thumbs stay on the PSISs.

• Note symmetry in motion. A positive test is when one PSIS moves higher than the opposite one. Note the side that moves higher. This indicates either sacroiliac restriction or dysfunction, or a tight hamstring on that side.

Seated flexion test is performed as follows:

• This is the standing test repeated with the patient sitting on a table, slid back far enough on the table so that the knees touch the edge of the table.

• The physician has the patient slouch forward while the thumbs are on the PSISs.

• This test takes out the hamstring as a cause of restriction, so a PSIS that moves more superiorly compared with the opposite side would be a positive test on that side and indicate lumbosacropelvic dysfunction on that side. Many times, this is positive on the same side as the injured or painful ankle.

Leg-length discrepancy testing is performed as follows:

• The physician holds the ankles as the patient lies supine on the table.

• The patient slides his or her feet towards his or her buttocks so the knees flex.

• Have the patient lift his or her hips up in the air—bridging.

• The patient brings his or her hips back down on the table.

• The physician holds one ankle in each hand, pulling the legs towards him or her to take up slack.

• The physician places thumbs on the inferior aspect of the medial malleoli and assesses for symmetry. Note the side with the malleolus that is more superior.

• With the patient lying still, the physician moves to the pelvis and places his or her thumbs on both anterior superior iliac spines (ASISs). The thumbs should move from the inferior direction and push up against the protruding spines.

• Several different findings may be seen on one ASIS is compared with the other—superior, superior-anterior, out-flared, inferior, inferior-posterior.

• Note that this does not necessarily exclude an anatomic leg length discrepancy. A radiographic study would be necessary to rule that out, or a manipulative adjustment can be performed, and once the physician feels the dysfunctions are treated appropriately, the leg-length evaluation can be repeated.

Functional muscle testing is also performed as part of the core stability assessment.

Straight leg testing is performed as follows:

• The patient is supine. The physician holds the ankle or lower leg superior enough to not be putting pressure on a painful area.

• The physician instructs the patient to keep his or her leg completely straight (fully extended) and push his or her leg up as hard as he or she can.

• The physician repeats on the other side. The physician may use 2 hands to apply enough force to keep the leg from moving up, or if the patient is strong.

• Note differences in strength. Most differences are more subtle than +5/5 versus +4/5. Look for shakiness, an unstable effort, leg drifting medially, or a feeling from the patient that he or she "just can't push hard." Note quick fatigue against resistance. Even an elderly, weakened patient who has normal core function has a steady contraction against resistance without shakiness.

• If the patient seems even on both sides, quickly repeat the test. An inhibited side fatigues quickly, usually after only 2-3 repetitions.

Hip abduction testing is performed as follows:

• The patient lies on his or her side. Both legs are straight, and the torso should not be rotated.

• The physician holds the top leg in the same area around the ankle.

• The patient is instructed to keep the knee straight (fully extended) and extends the hip about 5-10°.

• The physician instructs patient to lift the leg up to the ceiling as hard as he or she can. The physician may use both hands to ensure stability.

• Note weakness, shakiness, or quick fatigue. Note any effort, intentional or not, of bringing the hip into flexion as the patient tries to abduct. That is a sign of compensation.

• Be aware of the position of the leg when testing. If the leg with extended knee is flexed slightly past 0°, the tensor fascia latae is doing the majority of the abduction. Since it is rarely inhibited in dysfunctions, the physician may have a false-positive test result. Some patients have a flexor contracture, making this more difficult. However, that could also be a compensation for the ankle.

Hamstring strength testing is performed as follows:

• The patient is prone with the knee flexed to no more than 10-20°. Any more flexion could make resisting the patient's hamstring difficult and potentially cause injury if the patient contracts without the physician being ready.

• The physician places one hand on the distal hamstring for stability and the other around the ankle.

• The physician instructs the patient to flex the knee hard against physician resistance.

• The physician looks for quick fatigue, easy cramping (while the opposite side does not cramp), weakness, or shakiness.

The information obtained through these tests can be included on a physical therapy prescription if the physician is not trained to perform manual medicine to realign the patient and free-up the restrictions that lead to this inhibition. Once the inhibition is removed, the patient's strength and stability improves immediately.

Differences in these tests indicate core instability related to inhibition of muscle firing and contraction. The core strength may already be weak enough to allow chronic malalignment and dysfunctions to exist, but many of these patients function without difficulty. When an injury occurs, the homeostasis that the neuromuscular system achieves can be disrupted, leading to chronic problems long after an injury heals.

Any chronic core instability can lead to recurrent dysfunctions and malalignment, which can prolong the problem. Manual medicine treatment should be paired with rehabilitation to stabilize and balance the core mechanics through 3-dimensional functional training.