Conquering Peroneal Tendinopathy In Athletes

Peroneal pathology can affect athletes in a wide variety of sports and activities. The complexity of peroneal tendon disorders can be compounded by the desire of athletes to get back to the field of play as soon as possible. Accordingly, these authors offer pertinent diagnostic insights, review conservative therapies and provide step-by-step tips on surgical treatment.

Peroneal tendon disorders in athletic patients offer a unique challenge to the foot and ankle surgeon. As important as it is to comprehend the pathology of these injuries and the treatment options, understanding the mentality and physical requirements of the athlete provides pivotal information for a successful outcome.

   Athletes are typically highly motivated individuals who are eager to return to their pre-injury functional status. The athlete population often has established adjunct medical providers to augment our plan of care. These adjunct medical providers include physical therapists and athletic trainers. However, when there are setbacks in the recovery process or less than desirable outcomes, athletes can become our most difficult patients. This can be exacerbated by direct loss of income or loss of scholarships. More severe effects include depression or other mood disturbances that can be associated with injuries in athletes.

   The will and desire of the athletes to return to their pre-injury level of competition warrants the need to work closely and in conjunction with all coaches, personal trainers, physical therapists and athletic trainers. A close and functional relationship with these caregivers can help speed the recovery process and prevent any complications or delays. Often, these professionals play an instrumental role in the decisions affecting an athlete’s care. Ultimately, one needs to consider these benefits and detriments when dealing with injured athletes.

   Peroneal tendon disorders are complex conditions that can cause a high degree of morbidity in our athletic patients. Athletes from a wide variety of sports can develop peroneal pathology including but not limited to those who participate in baseball, basketball, football, running, golf and gymnastics. Foot and ankle surgeons need to be well educated on the intricacies of these injuries in order to provide a level of care that will facilitate a return to a high level of activity while not potentiating further injury or avoidable loss of time away from the activity.

Understanding The Anatomy Of The Peroneal Tendon Injury

Differentiating peroneal tendon pathology from other conditions of the lateral ankle complex is the first step in providing optimal treatment for these injuries. Assessment of the peroneal tendon complex should be a routine part of the examination with every patient who presents with an inversion ankle injury. A thorough understanding of the anatomy and etiology of lateral ankle injuries — in addition to a comprehensive physical exam — provides the knowledge base needed to differentiate peroneal tendon disorders from just a simple ankle sprain.

   The peroneus longus and brevis originate from the lateral surface of the fibula with the brevis muscle belly originating and extending more distally. The tendons run parallel to each other and in a common sheath as they course distally through the retromalleolar groove of the fibula. The tendons subsequently bifurcate at the level of the peroneal tubercle.

   This common tendon sheath passes through a fibro-osseous tunnel, where the primary resistance to subluxation comes from the superior peroneal retinaculum. The brevis courses anterior to the longus at this level. Distally, the brevis passes superior to the peroneal tubercle and inserts onto the fifth metatarsal tuberosity. When it comes to inversion injuries, there is often a tearing at the insertion.

   The peroneus longus sits posterior to the peroneus brevis at the level of the superior peroneal retinaculum. Then it extends inferior to the peroneal tubercle as it courses into the foot. The peroneus longus ultimately passes through the peroneal groove of the cuboid to insert on the plantar aspect of the medial midfoot and first ray.

   Both the peroneus longus and brevis tendons act as evertors and weak plantarflexors of the foot while providing dynamic stability to the lateral ankle complex. At the level of the ankle, the peroneal tendon complex is susceptible to injury whenever there is increased stress to the superior peroneal retinaculum. Overcrowding of the retromalleolar groove can lead to increased stress on the superior peroneal retinaculum. This can be the result of anatomic anomalies including a low lying peroneus brevis muscle belly, a shallow fibular groove or the presence of a peroneus quartus. When the foot is in a plantarflexed or everted position, the peroneal tendons translate laterally and anteriorly, resulting in greater pressure on the superior peroneal retinaculum. Forceful contraction of the peroneal tendons in this position can lead to increased strain on the superior peroneal retinaculum.

   Once the strength of the superior peroneal retinaculum is insufficient to the pressures acting upon it, subluxation and dislocation of the peroneal tendons result. The peroneus brevis then functions against the sharp ridge of the posterior lateral fibula, resulting in longitudinal tearing and splitting. As the injury progresses, the peroneus longus can also be affected.

   As the tendons pass below the ankle, the tendons can be affected by structural abnormalities including a hypertrophic peroneal tubercle or calcaneal fracture.1,2 These conditions can lead to direct irritation of the tendons as they pass over the lateral aspect of the calcaneus. Repetitive traction of the peroneus brevis on the fifth metatarsal tuberosity can lead to insertional tendonitis.

Essential Pearls On Making A Diagnosis

The differential diagnosis for lateral ankle pain can include but is not limited to: peroneal tendon pathology, lateral ankle ligament injury, fracture, osteochondral lesion or sural nerve entrapment. When differentiating peroneal tendon disorders from these other conditions, ascertaining an accurate history of the mechanism of injury is key. The most common presentation is an athlete with subjective complaints of a possible ankle sprain after sustaining an inversion type of injury.

   Subjectively, complaints may be as subtle as pain mimicking a simple sprain or as specific as a popping or snapping sensation, which may indicate a peroneal subluxation. The surgeon can narrow down the diagnosis when an athlete is able to describe the scenario of the injury, allowing the recognition of the specific foot position and deforming force.

   For instance, a forced dorsiflexion of the ankle or eversion of the foot with intense contraction of the peroneals — which can occur with injuries related to skiing or other sports — can cause acute tendon subluxation, tears or even rupture. Pivoting motions against resistance can cause similar injuries that may occur in baseball pitchers, golfers, running backs and wide receivers. Ballet dancers or gymnasts are often required to be in the en pointe position, which can lead to subluxation or tendonitis.

   One must perform a comprehensive lower extremity physical exam when evaluating peroneal tendon injuries. Suprastructural deformities, including cavus or “subtle cavus” foot types, distal tibia varus, or rigid forefoot varus, may subject the peroneal tendon complex to increased forces and result in injury.3,4 Although these deformities are less common in our athletic population, a patient presenting with a cavus foot type should undergo evaluation for underlying neuromuscular problems.

   When evaluating peroneal tendon disorders, it is important to be able to assess the lateral ankle pain and associated lateral ankle insufficiency. Sprains are typically characterized by point tenderness to the anterior talofibular and/or calcaneofibular ligaments. In evaluating for lateral ankle insufficiency, utilize anterior drawer and talar tilt exams to check for positive findings.

   Localized findings with peroneal tendon disorders include pain and swelling along the course of the tendons. When possible, utilize manual muscle testing to isolate injuries to the peroneus longus or brevis tendon. Active eversion against resistance to the lateral rearfoot can assess the integrity of the peroneus brevis tendon. Active plantarflexion of the first ray against resistance can be helpful in assessing the integrity of the peroneus longus tendon. The compression test as described by Sobel and colleagues can aid in the diagnosis of peroneus brevis pathology.5 One can reproduce subluxation by holding the foot in dorsiflexion and performing active eversion against resistance. However, these tests may be difficult for athletes to perform in the presence of acute injury when they are guarding against further injury.

How To Utilize Imaging Effectively

Take basic radiographs of the foot and ankle to rule out bony pathology including fractures, coalitions, osteoarthritis and a hypertrophic peroneal tubercle. Also use these radiographs to assess the os peroneum. A fleck sign on the anterior aspect of the distal fibula visible in a mortise view of the ankle can represent an avulsion of the superior peroneal retinaculum. Hindfoot alignment views are important to assess for any structural abnormalities — such as calcaneal or distal tibial varus — that will exacerbate peroneal tendinopathy. Alternative advanced imaging including bone scintigraphy or computed tomography (CT) may be indicated when one suspects bony pathology. Static or dynamic ultrasound can be useful to detect tears or thickening of the tendons although this is highly operator dependent.6

   Magnetic resonance imaging (MRI) is our preferred method of imaging. Time and return to sport are key factors in treating the competitive athlete. Therefore, we institute MRI early on in the management of the athletic patient. The MRI findings of tendonitis, longitudinal tears or tenosynovitis are visible on T2-weighted and short tau inversion recovery images. Partial tears are visible as thickening with heterogeneous signal intensity. One can identify complete tears when there is discontinuity of the tendon.7 Tears of the peroneus brevis demonstrate a flattened or boomerang shaped appearance between the retromalleolar groove and the peroneus longus.

   Research has demonstrated the sensitivity and specificity of MRI in peroneal tendon injuries to be around 83 percent and 75 percent respectively.8,9 However, reliance on MRI findings alone for diagnosis can lead to unnecessary intervention. A recent study by Park and colleagues demonstrated a positive predictive value and negative predictive value of 66.7 percent and 88.4 percent respectively when they compared MRI findings to operative findings.7 These studies validate the importance of incorporating the findings from a thorough physical examination into the surgical plan, and not relying on the MRI for sole evaluation of peroneal tendon pathology.

   In addition to evaluating the integrity of the peroneal tendon complex, the ability to assess associated soft tissue and bony pathology with MRI is particularly important in our athletic patients. In a study comparing preoperative MRI findings to intraoperative findings, Lamm and colleagues identified anterior talofibular ligament rupture in 50 percent of patients and identified a flattened or convex fibular groove in 78 percent of patients.9 Furthermore, they identified a low-lying muscle belly and the presence of a peroneus quartus in 25 percent and 17 percent respectively in their patient population. These findings reaffirm that peroneal tendon injuries are complex conditions that can have a high rate of associated pathology. Incorporating these coexisting conditions into the treatment plan is essential to achieving a successful outcome.

Salient Insights On Conservative Treatment

In the absence of tendon rupture, one typically employs a period of conservative treatment for peroneal tendon injuries. The treatment modalities utilized are dependent primarily on the severity of the injury and symptoms.

   In regard to peroneal tendonitis or tendinosis, clinicians would manage this with the RICE (rest, ice, compression and elevation) protocol, nonsteroidal anti-inflammatory (NSAID) medication, activity modification and bracing. Athletes with a definitive time frame for return to activity typically are non-weightbearing in a removable walking boot for a period of one to two weeks and then undergo physical therapy. The focus of physical therapy in this phase is on resolution of inflammation, improvement in the ankle range of motion (ROM) and strengthening of the ankle stabilizers. The use of physical therapy can address inflammation with multiple modalities including cryotherapy, therapeutic ultrasound and iontophoresis.

   Physical therapy can also address additional deficits in proprioception and ankle ROM. Patients with midseason injuries typically receive braces for the remainder of the season. Removal from activity is warranted with athletes experiencing significant pain or alteration of normal biomechanics that could lead to further injury. Utilize long-term bracing with cases of recurrent tendonitis and lateral ankle instability.

   Additionally, one should manage peroneal tears with a period of non–weightbearing followed by protected weightbearing in a removable walking boot for four to six weeks. With these athletes, initiate early physical therapy in order to address deficits in ROM and proprioception. One can utilize a custom fit brace or a high quality off the shelf brace to provide additional stability to the peroneal complex, and prevent future lateral ankle injury.

   Conservative treatment for painful peroneal subluxation is associated with higher failure rates.10 It is important to make athletes aware of the odds of conservative success so they are able to make an educated decision regarding their treatment plan. Often, this will include deferring conservative treatment for immediate surgical intervention. When one utilizes conservative treatment for peroneal subluxation, it is more aggressive in comparison to treatment for isolated tendonitis or tendinosis, and includes longer periods of non-weightbearing and bracing. We typically utilize immobilization in a removable walking boot and follow this with physical therapy and long-term bracing.

   Physical therapy is an important resource when it comes to treating athletes with peroneal tendon injuries. We utilize physical therapy both with patients treated conservatively and surgically. In addition to improving muscle strength, ROM and proprioception, physical therapists can evaluate an athlete’s ability to perform sport specific movements. The ability to perform these movements pain-free is a requirement before the athlete is allowed to return to sport.

Pertinent Pointers On Surgical Decision Making

The decision for surgical intervention for peroneal tendon pathology can be complicated when dealing with athletes. One needs to assess the possible degree of disability and the likelihood of further injury when forming a treatment plan. If left untreated, subluxation of the peroneals can lead to tendon tears or ruptures, and further long-term damage. Any injury that causes an athlete to deviate from the normal biomechanics may predispose the athlete to a secondary injury. A prospective study in the American Journal of Epidemiology found high school athletes with a previous injury to be twice as likely to be reinjured in comparison to athletes with no prior injury.11 In regard to the decision to undergo surgical intervention, the surgeon discusses this idea earlier on in the treatment plan when it comes to athletes with peroneal subluxation or other contributing pathology.

   The timing of surgical intervention can be very important in our athletic patients. Consider aggressive non-surgical treatment, such as functional bracing and daily rehabilitation, when patients are in season and demonstrate normal biomechanics with minimal pain. The beginning of the off-season is the ideal time for surgical intervention as this allows for a proper healing and rehabilitation. With year-round athletes, the timing of surgery may be of less importance. One should consider surgery after conservative treatment has failed and it should be based on the severity of symptoms and type of pathology.

A Step-By-Step Approach To Surgical Intervention

Surgical intervention for peroneal tendon injuries should address both tendon pathology and associated deformities. Isolated tendon debridement or repair, in the presence of concomitant deformities, may lead to less than desirable results. Other associated conditions that one may need to address include lateral ankle instability, osteochondral lesions or varus deformities.

   Typical exposure of the peroneal tendon complex includes a curvilinear incision beginning proximal to the ankle joint over the posterior fibula and extending distally along the course of the peroneal tendons to the level of the peroneal tubercle. After carrying dissection down to the superior peroneal retinaculum and tendon sheath, perform active circumduction to evaluate for the presence of subluxation.

   Although it is less common, intrasheath subluxation can occur. This involves the tendons switching their alignment while maintaining position in the fibular groove.12 When gross subluxation or intrasheath subluxation is present, the surgeon should evaluate the local anatomic etiology. This evaluation includes identification of a shallow fibular groove, a low-lying peroneus brevis muscle belly and the presence of peroneus quartus. Excise these soft tissue anatomic anomalies to decompress the fibular groove and reduce the potential for subluxation.

   After incising the common tendon sheath, displace the tendons from the fibular groove and inspect them. When present, excise inflamed synovial tissue. Evaluate tears in the peroneal tendons according to their cross-sectional involvement. In regard to tears with less than 50 percent involvement, perform direct debridement with or without tubularization. When it comes to tendons with a flattened appearance and greater percentage of tendon involvement, perform tubularization with non-absorbable sutures. To reduce soft tissue irritation, bury the suture knots within the tubularized portion of the tendon.

   Tears with more than 50 percent involvement typically receive proximal and distal tenodesis using non-absorbable sutures. Those percentages are important guidelines as the ultimate decision is based on the intraoperative assessment of the tendon and the quality of the remaining tendon. Consider tendon graft or local tendon transfer in the presence of a decreased tendon excursion.

   Create a shallow fibular groove to reduce the potential for chronic subluxation. Researchers have described numerous techniques to deepen the retromalleolar groove and prevent resubluxation.13-15 Other procedures include simple bony resection, fibula bone block advancements or periosteal flaps.

   The approach we typically utilize with athletic patients is an intramedullary groove deepening procedure as described by Mendicino and colleagues.16 One would perform graduated intramedullary reaming of the posterior aspect of the fibula, taking care not to invade the gliding surface of the fibula. The surgeon can easily perform this under fluoroscopic image intensification. Gently impact the posterior surface with a bone tamp. Doing so allows for an increase in groove depth while maintaining a smooth surface for the tendons to glide over in the fibular groove.

   In addition to repair of direct tendon and fibular groove pathology, evaluate the competency of the superior peroneal retinaculum. Insufficiencies associated with the retinaculum can range from fracture or separation of the fibrocartilagenous lip to simple attenuation. Restoration of the integrity of the retinaculum is the goal for these types of injuries.

   Our most commonly employed technique in this scenario involves resection of redundant retinaculum with advancement of the retinaculum. The surgeon advances the posterior aspect of the superior peroneal retinaculum anteriorly and secures it to the posterior lateral ridge of the fibular using non-absorbable sutures passed through drill holes. Advance the anterior aspect of the retinaculum posteriorly and suture it in a pants-over-vest fashion to the posterior portion of the retinaculum. At the completion of the procedure, perform circumduction of the ankle to ensure adequate stability of the tendons in the retromalleolar groove.

Ensuring A Smooth Postoperative Course

Postoperative protocols depend on the procedures one performs. In the absence of osteotomies or arthrodesis procedures, our postoperative course for peroneal repairs includes a 10- to 14-day period of non-weightbearing in a combined compression dressing and posterior splint until we remove the sutures. During the next two weeks, the patient wears a removable walking boot and physical therapy begins with a focus on early mobilization and edema control.

   At four to six weeks, the patient may start protected weightbearing. Physical therapy sessions focus on improving range of motion and strengthening of the peroneal complex. One should utilize deconditioning prevention in physical therapy and can include strengthening exercises of the hip and thigh muscle groups.

   By six to eight weeks after surgery, the patient may gradually return to modified activities. With athletes who have undergone concomitant bony procedures, there is a greater delay with return to activity and the extended rehabilitation course.

   The clinician must have a good understanding of the functional requirements needed to participate effectively in their athletes’ respective sport prior to allowing a return to full activity. This knowledge is useful when coordinating a rehabilitation plan with the physical therapist. Prior to resuming full activity, the athlete should meet specific criteria outlined by the surgeon and physical therapist. These criteria should include but are not limited to: ankle ROM; muscle strength; proprioception; and sport specific movements. It is in this phase of treatment that a good relationship with the athlete’s adjunct medical providers and coaches can help return the athlete to play effectively and as quickly as possible.

In Summary

Peroneal tendon injuries are complex conditions that can cause significant pain and functional limitations in our athletic patients. A proper workup includes a thorough history with a physical exam and, when appropriate, advanced imaging. Athletes can achieve a successful return to sport with non-surgical or surgical treatments, depending on the severity of the injury. Effective surgical intervention needs to include the repair of tendon specific pathology as well as the correction of other underlying contributing conditions. Functional rehabilitation is essential in the treatment of these conditions and can help improve outcomes with both conservative and surgical treatments.

   The direct correlation between a patient’s quality of life and maintaining a high level of activity is what separates the athlete from the sedentary patient. Understanding this relationship will help the foot and ankle surgeon provide an unmatched level of care to our patients.

   Dr. Reeves is an Attending Physician with the Florida Hospital East Orlando Residency Training Program. He is a Fellow of the American College of Foot and Ankle Surgeons, and a Diplomate of the American Board of Podiatric Surgery.

   Dr. Shane is an Attending Physician with the Florida Hospital East Orlando Residency Training Program. She is a Fellow of the American College of Foot and Ankle Surgeons, and a Diplomate of the American Board of Podiatric Surgery.

   Dr. Glesne is a third-year resident with the Florida Hospital East Orlando Residency Training Program.

   Dr. Wilson is a third-year resident with the Florida Hospital East Orlando Residency Training Program.

References

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   For further reading, see “When Conservative Care Fails For Tendinopathies” in the January 2009 issue of Podiatry Today. To access the archives, visit www.podiatrytoday.com.