Flexor hallucis longus tendon injury in dancers and nondancers

Do Patients With Functional Hallux Limitus Have a Low-Lying or Bulky FHL Muscle Belly?

Background

Functional hallux limitus (FHLim) refers to a limitation of hallux dorsiflexion when the first metatarsal head is under load, whereas physiologic dorsiflexion is measured in the unloaded condition. Limited excursion of the flexor hallucis longus (FHL) in the retrotalar pulley has been identified as a possible cause of FHLim. A low-lying or bulky FHL muscle belly could be the cause of this limitation. However, to date, there are no published data regarding the association between clinical and anatomical findings. The purpose of this anatomical study is to correlate the presence of FHLim and objective morphologic findings through magnetic resonance imaging (MRI).

Methods

Twenty-six patients (27 feet) were included in this observational study. They were divided into 2 groups, based on positive and negative Stretch Tests. In both groups, we measured on MRI the distance from the most inferior part of the FHL muscle belly and the retrotalar pulley as well as the cross-sectional area of the muscle belly 20, 30, and 40 mm proximal to the retrotalar pulley.

Results

Eighteen patients had a positive Stretch Test and 9 patients had a negative Stretch Test. The mean distance between the most inferior part of the FHL muscle belly and the retrotalar pulley was 6.0 ± 6.4 mm for the positive group and 11.8 ± 9.4 mm for the negative group (P = .039). The mean cross section of the muscle measured at 20, 30, and 40 mm from the pulley were 190 ± 90, 300 ± 112, and 395 ± 123 mm² for the positive group and 98 ± 44, 206 ± 72, and 294 ± 61mm² for the negative group (P values .005, .019, and .017).

Conclusion

Based on these findings, we can conclude that patients with FHLim do have a low-lying FHL muscle belly causing limited excursion in the retrotalar pulley. However, the mean volume of the muscle belly was comparable in both groups, and therefore bulkiness was not found to be a contributing factor.

Level of Evidence

Level III, observational study.

What Is the Efficacy of a Nonoperative Program Including a Specific Stretching Protocol for Flexor Hallucis Longus Tendonitis?

BACKGROUND

Diagnosis and treatment of tendonitis/entrapment of the flexor hallucis longus (FHL) has been sporadically described in the evidence, primarily in the context of dancers and other athletes. Although various nonspecific nonoperative treatments have been described, it is not clear how often they achieve a satisfactory amount of symptom improvement.

QUESTIONS/PURPOSES

The present study was designed to address the following questions regarding the nonoperative treatment of FHL tendonitis: (1) In a population of patients where the default management option for FHL tendonitis is a comprehensive nonsurgical approach, what proportion of patients thus treated opted not to have surgery? (2) What factors were associated with a patient's decision to undergo surgery after a period of nonsurgical management?

METHODS

The 656 patients included were all those diagnosed with FHL tendonitis who were initially treated nonoperatively in the foot and ankle division between January 2009 and December 2018. Demographics, comorbidities, examination findings, imaging results, pain scores, treatment instituted, and final outcome were obtained from the electronic medical record. The primary outcome was the decision to have surgery due to unsatisfactory symptom improvement. We compared patients who opted for surgery with those who did not after nonoperative treatment with univariable and multivariable statistics using demographics, comorbidities, and clinical findings as potential risk factors, with p < 0.05.

RESULTS

Forty-four percent (180 of 409) of patients decided to forgo surgery after the institution of a specific FHL stretching program. Surgery was more likely in patients with clinical hallux rigidus (OR 2.4 [95% CI 1.16 to 4.97]; p = 0.02) or posteromedial ankle pain (OR 1.78 [95% CI 1.12 to 2.83]; p = 0.01) and less likely in those who completed an FHL stretching program (OR 0.15 [95% CI 0.08 to 0.27]; p < 0.001).

CONCLUSION

FHL tendonitis is more common than the previous evidence suggests and frequently occurs in nonathletes. Once it was diagnosed by detection of tenderness anywhere along the tendon, most frequently at the fibroosseous tunnel, nonoperative treatment focused on specific FHL stretching and immobilization in more severe cases reduced the symptoms to the extent that 44% of patients decided that surgery was unnecessary. The key to its diagnosis is awareness that this injury is possible because most patients treated in this study had been previously seen by orthopaedic providers who had not appreciated the presence of the condition, leading to a delay in diagnosis and treatment of more than a year in many patients.

LEVEL OF EVIDENCE

Level III, therapeutic study.

MRI findings of tibialis anterior friction syndrome: a mimic of tibial stress injury

OBJECTIVE

To describe a distinct constellation of MRI demonstrated soft tissue abnormalities centred around the tibialis anterior tendon in a subset of patients presenting as suspected tibial stress injury.

MATERIALS AND METHODS

A retrospective review was performed of the clinical and MRI imaging findings from 5 selected patients referred for MRI with suspected tibial stress injury. MRI studies at presentation of each case were systematically reviewed for peritendinous fluid, tibialis anterior tendon change, tibialis anterior muscle and myotendinous junction oedema, periosteal oedema over the tibia and tibial marrow oedema.

RESULTS

All 5 cases were athletes (3 soccer players, 2 runners) of between 20 and 40 years of age. On MRI, all 5 cases demonstrated peritendinous fluid around an intact tibialis anterior tendon. This fluid was maximal at the junction of mid and distal thirds of the lower leg, and extended down to the superior extensor retinaculum, with a mean cranio-caudal length of 13 cm (range 8-17 cm). Associated oedema was present in the surrounding subcutaneous tissue, tibial periosteum and distal tibialis anterior musculotendinous junction.

CONCLUSION

Peritendinous fluid around an intact tibialis anterior tendon over the mid-to-distal third tibia, with surrounding subcutaneous, periosteal and tibialis anterior myotendinous junction oedema is demonstrable on MRI in a subset of patients presenting as suspected tibial stress injury. A friction syndrome of tibialis anterior between the superior extensor retinaculum and the anterior tibia is proposed as the aetiology of this entity.

Increased flexor hallucis longus tension decreases ankle dorsiflexion

BACKGROUND

Restricted excursion of the flexor hallucis longus (FHL) is associated with several clinical problems. An FHL excursion measurement device (EMD) was used to objectively assess differences between patients with clinically normal or tight FHL tendons.

METHODS

188 patients (356 feet) were enrolled. The EMD measured maximum ankle dorsiflexion with the great toe in 15°, 30°, and 45° of dorsiflexion. All had clinical assessment of FHL tightness by their provider independently of the EMD measurement.

RESULTS

Increased hallux DF always caused decreased ankle DF. Patients with clinically tight FHLs demonstrated decreased ankle DF compared to normal subjects at all hallux positions (p<0.01). The EMD measurement was not sensitive enough for detection of FHL tightness in individuals. A clinically tight FHL was seen in almost 50% of feet.

CONCLUSIONS

Tension in the FHL can limit ankle DF. Clinical tightness of the FHL is likely more common than currently recognized.

Recalcitrant Flexor Hallucis Longus Dysfunction: A Case Study Demonstrating the Successful Application of an Adaptable Rehabilitation Program With a Two-Year Follow-Up

Flexor hallucis longus (FHL) dysfunction is a condition experienced primarily by athletes, including ballet dancers and runners. Accurate diagnosis and definitive treatment at the initial evaluation can often be difficult given the number of foot and ankle pathologies that share similar signs and symptoms. The evaluation process tends to be a diagnosis of inclusion rather than a specific pathology with an accepted rehabilitation plan. For example, patients with medial arch pain may undergo an extended rehabilitation period with an evolving differential diagnosis requiring several treatment modifications. A more appropriate rehabilitation paradigm should adapt to the potential changes in patient symptoms and presentation, addressing functional impairments as they arise. This case study describes the successful management of a patient with chronic FHL dysfunction, leveraging a flexible, multimodal treatment approach to address the evolving functional impairments rather than focusing on a single, discrete diagnosis. At a two-year follow-up, the patient remains pain-free.

Effects of a "toes-off" modified heel raise on muscle coordination in non-dancers, dancers, and dancers with flexor hallucis longus tendinopathy

BACKGROUND

Tendinopathy of the flexor hallucis longus, commonly called "dancer's tendinitis", is a prevalent injury among female ballet dancers. Limited success of non-surgical interventions leads to many dancers undergoing tenolysis surgeries with risks and recovery times that can be detrimental to a dance career. The purpose of this study was to evaluate lower limb kinematics and muscle coordination during a modified traditional heel raise exercise where the toes hang off the edge of the support surface. We hypothesized this would decrease activation of the flexor hallucis longus and increase activation of larger plantarflexors.

METHODS

Healthy non-dancers (n = 11), healthy dancers (n = 10), and dancers with flexor hallucis longus tendinopathy (n = 9) performed traditional ("toes-on") and modified ("toes-off") heel raises with kinematic and electromyographic instrumentation of the lower leg.

FINDINGS

Participants maintained ankle excursion with the toes-off modification, while metatarsophalangeal joints had reduced excursion and greater excursion variability. Most healthy dancers (9/10) decreased flexor hallucis longus activation as predicted, but dancers with flexor hallucis longus tendinopathy showed a variable response with some decreasing activation (3/9) but others increasing activation up to 4-times. There were no changes in activation of other plantarflexors. Across groups, intrinsic foot muscle activation decreased with the toes-off modification.

INTERPRETATION

The toes-off modification decreased flexor hallucis longus activation in most of the healthy dancers but was insufficient to shift muscle coordination from the flexor hallucis longus to larger plantarflexors in dancers with flexor hallucis longus tendinopathy. Future work should investigate clinical cues or modifications to this "toes-off" heel raise intervention.

Posterior Ankle Impingement and Flexor Hallucis Longus Pathology

Posterior ankle pain is a common complaint, and the potential causative pathologic processes are diverse. The constellation of these numerous etiologies has been collectively referred to as posterior ankle impingement syndrome. The pain associated with posterior ankle impingement is caused by bony or soft tissue impingement of the posterior ankle while in terminal plantar flexion. This condition is most frequently encountered in athletes who participate in sports that involve forceful, or repetitive, ankle plantar flexion. This article discusses the associated pathology, diagnosis, conservative treatment, and surgical techniques associated with flexor hallucis longus and posterior ankle impingement syndrome.

Neglected Iatrogenic Flexor Hallucis Longus Tendon Rupture After Haglund's Endoscopic Surgery: A Case Report

Rupture of the flexor hallucis longus (FHL) tendon is a rare condition that can occur with direct or indirect trauma; most of the injuries are complete ruptures resulting from laceration. Endoscopic calcaneoplasty is used for treatment of symptomatic Haglund's deformity, and complications of this procedure are rare. Iatrogenic FHL tendon rupture occurring after endoscopic calcaneoplasty has not been reported previously. This case report presents a rare complication after endoscopic calcaneoplasty and the proper method of treatment.

Effect of extensive tenosynovectomy on diffuse flexor hallucis longus tenosynovitis combined with effusion

OBJECTIVE

The objective of this study was to examine the clinical and magnetic resonance imaging (MRI) outcomes of extensive tenosynovectomy on patients with diffuse flexor hallucis longus tenosynovitis combined with effusion (DFHLT-E).

METHODS

Consecutive patients undergoing extensive tenosynovectomy for DFHLT-E in the same foot and ankle center from January 2013 to December 2016 were selected; a total of 14 patients were included in the final analysis. Patients with a minimum 1-year follow-up were evaluated with physical examination, MRI, American Orthopaedic Foot and Ankle Society (AOFAS) clinical midfoot scale, and visual analog scale (VAS) pain scores.

RESULTS

The 14 patients were followed up for an average of 15.0 ± 2.3 months (12-18 months). There were no recurrences in all clinical examinations at the final follow-up. The AOFAS score was improved from 61.57 ± 10.70 before surgery to 90.28 ± 9.41 at the final follow-up. The difference was statistically significant (p = 0.001). The VAS score was improved from 4.00 ± 0.82 before surgery to 0.43 ± 0.53 at the final follow-up (p < 0.001). MRI examination revealed two patients with small residual and limited effusion with no clinical symptoms. Superficial pin infection was observed in one patient, and two patients had transient neurostimulation.

CONCLUSIONS

Extensive tenosynovectomy is an effective alternative for the treatment of DFHLT-E with less complications or recurrence.

Does Function Determine the Structure? Changes in Flexor Hallucis Longus Muscle and the Associated Performance Related to Dance Modality: A Cross-Sectional Study

Background and Objectives: Flexor hallucis longus pathology is one of the most common conditions of the ankle and foot in dancers, due to the high demand of dance movements performed in an extreme plantar flexion and dorsiflexion range of motion. The objectives of this study were to determine the bilateral differences between the thickness and cross-sectional area of the flexor hallucis longus muscle in dancers, to establish possible differences between dance modalities, and to analyze whether there is a correlation between ultrasonographic parameters or performance variables and the dance modality. Material and Methods: A sample of 50 (29 classical and 21 contemporary) full-time pre-professional female dancers were included in the study. The thickness and cross-sectional area of the flexor hallucis longus muscle were evaluated for both limbs using ultrasound imaging. The range of movement of the first metatarsophalangeal joint was measured using functional extension with maximal ankle plantarflexion, balance was measured in a unilateral stance with the heel raised, endurance was evaluated through a modified heel rise fatigue test, and a counter movement jump to assess the vertical jump performance was measured bilaterally. Results: There were no significant differences recorded between the dominant and non-dominant limbs for each variable, within both groups. Contemporary dancers showed a greater thickness and cross-sectional area of the flexor hallucis longus muscle than classical dancers. However, classical dancers showed an increase of balance, endurance, range of movement of the first metatarsophalangeal joint, and counter movement jump with respect to contemporary dancers. Conclusion: Bilateral symmetry was identified in all variables for both groups. The size and performance of the flexor hallucis longus muscle may be influenced by the specific nature of dance modality.

Posterior Arthroscopic Treatment of a Massive Effusion in the Flexor Hallucis Longus Tendon Sheath Associated with Stenosing Tenosynovitis and Os Trigonum

We report a rare case of massive accumulation of fluid in the flexor hallucis longus tendon sheath with stenosing tenosynovitis and os trigonum. A 34-year-old woman presented to our hospital with pain and swelling in the posteromedial aspect of the left ankle joint after an ankle sprain approximately 8 months earlier. There was tenderness at the posteromedial aspect of the ankle, and the pain worsened on dorsiflexion of the left great toe. Magnetic resonance imaging revealed massive accumulation of fluid around the flexor hallucis longus tendon. We removed the os trigonum, performed tenosynovectomy around the flexor hallucis longus, and released the flexor hallucis longus tendon via posterior arthroscopy using standard posterolateral and posteromedial portals. At 1 week postoperatively, the patient was asymptomatic and able to resume her daily activities. There has been no recurrence of the massive accumulation of fluid around the flexor hallucis longus tendon as of 1 year after the surgery. To our knowledge, this is a rare case report of extreme massive effusion in the flexor hallucis longus tendon sheath with stenosing tenosynovitis and os trigonum treated successfully by removal of the os trigonum, tenosynovectomy around the flexor hallucis longus, and release of the flexor hallucis longus tendon via posterior ankle arthroscopy.

The accuracy of an injection technique for Flexor hallucis longus tendon sheath: A cadaveric study

BACKGROUND

Corticosteroid injections are used in the conservative treatment of Flexor hallucis longus (FHL) tendinopathy. Studies for imaging guided injection are done, however, the accuracy of blind injection has not yet been studied.

PURPOSE

The aim of this study was to determine the accuracy of a blind injection technique into the FHL tendon sheath.

HYPOTHESIS

We hypothesize that a blind injections technique into the FHL tendon sheath based on clinical examination has a high accuracy.

STUDY DESIGN

Descriptive cadaveric study.

METHODS

Ten ankles of human cadavers were blindly injected with radiologic contrast mixed with methylene blue into the FHL tendon sheath. After injection, a CT scan of each ankle was performed to evaluate the location of contrast material. CT scans were reviewed by an experienced musculoskeletal radiologist blinded to the procedure. Anatomic dissection was undertaken to assess the location of the injection fluid.

RESULTS

In nine ankles the radiological contrast was injected in the FHL tendon sheath. In one cadaver there was a technical problem and was therefore excluded.

CONCLUSION

This study shows that the FHL tendon sheath can be blindly injected based on only clinical examination with high accuracy.

LEVEL OF EVIDENCE

Descriptive cadaveric study.

Closed atraumatic complete rupture of the flexor halluces longus tendon during forward lunge exercise: A case report

RATIONALE

Acute rupture of the flexor halluces longus (FHL) tendon due to trauma or laceration is a well-known phenomenon. Partial rupture of the FHL tendon caused by tendinitis or stenosing tenosynovitis is common in ballet dancers and athletes. However, atraumatic complete rupture of the FHL is rare: as of 2018, only 7 cases of closed atraumatic complete rupture of the FHL tendon have been reported in the literature. Here, we report on a patient who presented with a closed atraumatic complete rupture of the FHL tendon during a forward lunge exercise.

PATIENT CONCERNS

A 35-year-old female visited the clinic with pain in the plantar medial aspect of the left foot, along with weakness and loss of great toe flexion. The patient had a normal foot structure and no history of trauma or systemic disease. She performed a forward lunge exercise more than 50 times on 1 leg per day, more than once a week to strengthen her leg muscles. She reported that she felt a slight pain in her left, great toe while exercising for 3 weeks prior to her visit. One week prior to presentation, severe pain occurred suddenly when her left hallux dorsiflexed strongly during an anterior lunge exercise motion.

DIAGNOSIS

Magnetic resonance imaging revealed complete rupture of the FHL tendon near the level of the metatarsal head and neck junction. The lesion was prolonged, with the proximal end displaced to the metatarsal shaft region.

INTERVENTIONS

Complete rupture of the FHL tendon was treated with a primary suture.

OUTCOMES

At the 1-year follow-up, active plantar flexion of the interphalangeal joint was possible but joint function had a range of 0° to 25°. Flexion strength was reduced slightly, measuring about 70% when compared to the contralateral side, but flexion strength of the metatarsophalangeal joint was normal.

LESSONS

We describe an extremely rare case of complete rupture of the FHL tendon at the level of metatarsal head and neck junction. It should be understood that this injury can occur not only in professional athletes but also in the general public, and we recommend educating personal trainers on how to prevent it.

Ankle Injuries in Dancers

The term dance encompasses a broad range of different styles; much of the orthopaedic literature has focused on ballet dancers. Injury is common in dancers at all levels, and many serious dancers sustain multiple injuries as they progress through their career. Foot and ankle injuries are among the most common injuries experienced by dancers. These injuries include those that are specific to dancers because of the unique physical maneuvers required to effectively perform, but they can also include common injuries that may require relatively different treatment because of the physical demands of the dancer. Os trigonum syndrome and flexor hallucis longus tenosynovitis generally fall into the former category as they are injuries that are more prevalent in dancers due to the extreme plantarflexion involved in dancing, especially ballet, and the relative demand placed on the toe flexors, most notably the flexor hallucis longus. On the other hand, anterior ankle impingement occurs both in dancers and in the general public. In many cases, a team approach to treatment with knowledgeable physical therapists can obviate the need for surgical treatment. If surgical treatment proves necessary, good results can be achieved with sound surgical technique and a well thought-out rehabilitation program.

A semi-quantitative technique to assess excursion of the flexor hallucis longus

BACKGROUND

Recent research indicates that restriction in excursion of flexor hallucis longus (FHL) contributes to hallux rigidus development. As described in the literature, clinical evaluation of FHL excursion has poor interobserver reliability. A simple, inexpensive, easily used FHL relative excursion measurement device was developed and tested.

METHODS

64 subjects were enrolled with shoe size, height, weight, BMI, and age compared. Using a footplate and series of mechanical wedges, maximum ankle dorsiflexion was measured with the great toe in 15°, 30°, and 45° of dorsiflexion.

RESULTS

Ankle dorsiflexion decrease with progressive hallux dorsiflexion increase was statistically significant with a linear correlation (r²=.814 p<.001) and was not statistically related to shoe size, height, weight, BMI, or age.

CONCLUSIONS

This technique provides consistent assessment of the limitation to ankle dorsiflexion incurred by decreased FHL excursion, establishing groundwork for future studies to assess the relationship between diminished FHL excursion and FHL pathology.

Immediate effects of ultrasound-guided percutaneous neuromodulation versus physical exercise on performance of the flexor hallucis longus muscle in professional dancers: a randomised clinical trial

Background:

Ultrasound-guided percutaneous neuromodulation (US-guided PNM) is a minimally invasive intervention. This technique consists of the application of percutaneous electrical stimulation (PES) through an acupuncture needle-like electrode that is placed in close proximity to the nerve or motor point of the target muscle under ultrasound guidance.

Objective:

To examine the immediate effects of a stretching exercise, an eccentric exercise and US-guided PNM on the performance of the flexor hallucis longus (FHL) muscle in young dancers.

Methods:

Randomised clinical trial. A total of 45 dancers were divided into three groups: Stretching group, Eccentric group and PNM group. The following performance parameters were assessed: range of motion (ROM) of the first metatarsophalangeal joint, balance test and unilateral heel raise fatigue test.

Results:

There were no differences between these groups in baseline measurements; at the end of the study, mean balance and endurance values were only significantly higher for the PNM group compared to the Stretching (p = 0.007 and p < 0.001, respectively) and Eccentric groups (p = 0.003 and p < 0.001, respectively). The effect sizes were large for the balance (d = 0.8) and endurance (d = 1.83) tests in the PNM group. Both the Stretching and Eccentric groups exhibited improvements in ROM compared to their baseline values (p = 0.009 and p = 0.004, respectively), whereas there was no significant temporal improvement noted for the PNM group. The effect sizes with respect to ROM values were moderate for stretching (d = 0.6) and eccentric (d = 0.7) exercises.

Conclusion:

An isolated PES intervention provides a greater immediate increase in balance and muscular strength than an active stretching and eccentric exercise of the FHL muscle in young ballet dancers.

Reconstruction of Neglected Flexor Hallucis Longus Tendon Rupture: A Case Report

Isolated rupture of the flexor hallucis longus tendon is an unusual injury. We present the case of a neglected flexor hallucis longus tendon closed traumatic rupture at the plantar aspect of the first phalangeal head of the great toe in a middle-age male. The injury occurred while he was dancing. Because end-to-end tendon suture was impossible, the ensuing gap was repaired using a free plantaris tendon graft. We present the operative repair benefit of the flexor hallucis longus tendon rupture to regain the function and strength of the interphalangeal joint of the hallux, avoid extension of the distal phalanx, and maintain the longitudinal arch of the foot.

Endoscopic All-inside Repair of the Flexor Hallucis Longus Tendon in Posterior Ankle Impingement Patients

Longitudinal flexor hallucis longus (FHL) tendon tears are sometimes complicated by posterior ankle impingement syndrome (PAIS), especially in ballet dancers. In recent years, PAIS has been treated endoscopically, but it is difficult to suture FHL tendon tears endoscopically. In this report, we describe how to suture the FHL tendon endoscopically with the Meniscal Viper Repair system (Arthrex, Naples, FL). Without our endoscopic technique, when a patient is found to have a longitudinal tear of the FHL under endoscopy, we must choose to either neglect the tear or convert to an open repair. Open tendon suture techniques have reportedly had relatively good results but require a longer skin incision than endoscopic surgery for PAIS. Compared with the open repair, the advantages of our technique include earlier recovery, less pain, a lower rate of soft tissue complications, and improved healing through better preservation of the blood supply. This technique is an attractive and useful option because it is an easy and safe method for longitudinal FHL tendon tears.

Arthroscopic Synovectomy for Zone 2 Flexor Hallucis Longus Tenosynovitis

Tenosynovitis of the flexor hallucis longus tendon is a condition typically found in ballet dancers and sometimes in soccer players and is related to chronic overuse. It mostly involves the portion of the tendon behind the ankle joint. However, the portion of the tendon under the sustentaculum tali can also be involved. Open synovectomy requires extensive dissection. We report the technique of arthroscopic synovectomy of the deep portion of the flexor hallucis longus.

Disorders of the Flexor Hallucis Longus and Os Trigonum

Os trigonum syndrome with disease of the flexor hallucis longus tendon, so-called stenosing flexor tenosynovitis, is a common cause of posterior ankle impingement. Conservative treatment is the recommended first line of treatment, with secondary treatment options of either open or arthroscopic os trigonum excision with flexor hallucis longus retinaculum release. The arthroscopic approaches have gained popularity in the past decade because of less scarring, less postoperative pain, minimal overall morbidity, and earlier return to activities. However, comprehensive understanding of the anatomy of the posterior ankle is crucial to warrant successful outcomes and minimizing complications.

The management of posterior ankle impingement syndrome in sport: a review

A literature review has been undertaken to assess the efficacy of management of Posterior Ankle Impingement Syndrome with an emphasis on sport. The evidence is confined to Level IV and V studies. There is a lack of prospective studies on the natural history of this condition and the outcomes of conservative treatment. Dance dominates the literature accounting for 62% of reported sports. Forty-seven papers have reported on the surgical outcomes of 905 procedures involving both open and artho-endoscopic techniques. 81% of patients required excision of osseous pathology and 42% soft-tissue problems resolving. There is a lack of standardisation of outcome reporting particularly in the open surgery group. However, the complication rates are relatively low: 3.9% for open medial, 12.7% for open lateral and 4.8% for arthro-endocopic surgery. Return to sport appears quicker for all activities in the arthro-endoscopic group but comparison of long term outcomes is more difficult with no evidence supporting superior long term results of one technique over another. Soccer players appear to return more quickly to activity than dancers.

Posterior hindfoot arthroscopy: a review

In recent years, minimally invasive surgery has developed and progressed the standard of care in orthopaedics and sports medicine. In particular, the use of posterior hindfoot arthroscopy in the treatment of posterior ankle and hindfoot injury is increasing rapidly as a means of reducing pain, infection rates, and blood loss postoperatively compared with traditional open procedures. In athletes, hindfoot arthroscopy has been used effectively in expediting rehabilitation and ultimately in minimizing the time lost from competition at previous levels. Van Dijk et al were the first to describe the original 2-portal technique, which remains the most commonly used by surgeons today and forms the basis for this review. The current evidence in the literature supports the use of 2-portal hindfoot arthroscopy as a safe, primary treatment strategy for symptoms of posterior ankle impingement, including resection of os trigonum, treatment of flexor hallucis longus and peroneal tendon injury, treatment of osteochondral lesions of the ankle, and the resection of subtalar coalitions. In this review, we present where possible an evidence-based literature review on the arthroscopic treatment of posterior ankle and hindfoot abnormalities. Causes, diagnosis, surgical technique, outcomes, and complications are each discussed in turn.

Arthroscopic treatment of tenosynovitis of the flexor hallucis longus tendon

BACKGROUND

Tenosynovitis of the flexor hallucis longus (FHL) tendon is a condition typically found in ballet dancers and sometimes in soccer players and is related to chronic overuse. A traumatic cause for this situation, such as an ankle sprain, is considered rare. In case of failure of conservative treatment, the tendon can be surgically released, which is usually done through an open procedure. This article presents the results of an arthroscopic release of the FHL.

METHODS

Twenty-seven patients underwent surgery for FHL tenosynovitis over a period of 18 months. The mean age of the patients was 34 years. All patients related the onset of the condition with an ankle sprain. Eighteen patients were on worker's compensation and five had sport-related accidents. None of the patients was a professional athlete or a ballet dancer. The mean follow-up was 32 months. The outcome was measured with a satisfaction questionnaire and with the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scoring system.

RESULTS

The mean postoperative AOFAS score was 89 with 70% excellent or good results. Mean satisfaction rate was 4 (range, 0 to 5); 89% of the patients would undergo the procedure again. Twenty-two patients (81%) returned to the same level of activity in work and sports. A complication rate of 18% (five patients) and reoperation rate of 4% (one patient) were found.

CONCLUSION

Arthroscopic release of the FHL tendon was a valid procedure. It was a minimally invasive surgery that allowed good visualization of the involved structures and yielded good results. This condition can be related to trauma and is not an exclusive disease of ballet dancers or overuse.

Hallux saltans due to flexor hallucis longus entrapment at a previously unreported site in an unskilled manual laborer: a case report

Triggering of the big toe, or hallux saltans, is commonly due to stenosing tenosynovitis of the flexor hallucis longus at the fibro-osseous tunnel below the sustentaculum tali. It is a rare condition described mainly in female ballet dancers. This is hypothesized to be due to the en pointe position used in ballet, which puts enormous supraphysiologic loads on the flexor hallucis longus, predisposing it to injury. Trigger hallux is extremely uncommon in the general population. We are reporting a case of hallux saltans in an unskilled manual laborer, with the site of tendon entrapment just proximal to the medial malleolus in the distal leg, a hitherto unreported location of stenosis.

Subcutaneous rupture of the flexor hallucis longus tendon: a case report

It is well known that rupture of the flexor hallucis longus tendon can be associated with open injuries and that closed rupture of the flexor hallucis longus tendon is rare. Tendon injuries of the foot can occur secondary to direct, indirect, or repetitive injury. Repetitive tendon injuries can cause tendinitis or stenosing tenosynovitis. Tendinitis is associated with internal tendon injury that can present with tendon thickening, mucinoid degeneration, nodule development, or in situ partial tears. Stenosing tenosynovitis is the development of tendon adhesions within the tendon sheath that interfere with tendon gliding, known as trigger toe. The flexor hallucis longus tendon is susceptible to injury along its entire course. A total of 35 cases of complete or partial closed ruptures of the flexor hallucis longus tendon have been reported. We present the case of complete subcutaneous rupture of the flexor hallucis longus tendon associated with trauma at the proximal phalangeal head.

Ankle "sprains" during sport activities with normal radiographs: Incidence of associated bone and tendon injuries on MRI findings and its clinical impact

OBJECTIVES

To evaluate, with magnetic resonance imaging (MRI), the occurrence of bone and tendon injuries and their impact on clinical management in athletes with ankle trauma during sports activities having normal radiographs and referred to the orthopedic department as "ankle sprains".

METHODS

This was a prospective study of 54 patients. Clinical examination and MR imaging were done in order to have an accurate diagnosis and the incidence of those injuries.

RESULTS

Nearly half of the patients were found to have no ligament injury on MRI. Isolated bone bruises and isolated tendon injuries may share the same clinical signs with ankle sprains.

CONCLUSIONS

MRI-based clinical management has been adjusted for each case; beside the Grade 3 ligament injuries and the rare, but difficult to diagnose osteochondral lesions of the talus, partial weight bearing or short-immobilization were offered as treatment modalities for the rest of the patients avoiding unnecessary long-term treatments and rehabilitation exercises.

Sports-related injuries in the young female athlete

The number of females participating in sports continues to increase. Adolescent and preadolescent females are at a risk injury to both their open growth plates as well as their joints. The purpose of this article is to review the common injuries seen with the most popular sports with females. Mt Sinai J Med 77:307-314, 2010. (c) 2010 Mount Sinai School of Medicine.

Posterior calf injury

Acute injuries of the Achilles tendon are common among athletes and non-athletes alike. Injuries of other posterior calf muscles are far less common but should be considered in the differential, to ensure proper diagnosis and treatment of patients with calf injuries. This article focuses on these calf injuries, including injuries of the gastrocnemius, plantaris, soleus, and flexor hallucis longus, which may occasionally be mistaken for Achilles tendon disorders.

Contribution of the flexor hallucis longus to loading of the first metatarsal and first metatarsophalangeal joint

BACKGROUND

A recent clinical study suggested that restrictive tenosynovitis of the flexor hallucis longus (FHL) may play an important causative role in hallux rigidus. The goals of this research were to assess normal function of the FHL and the effect of restricted FHL gliding on the loading of the hallux metatarsophalangeal joint (MTPJ). We hypothesized that proximal displacement of the FHL would increase the forces carried by the FHL tendon, causing increased loading of the first metatarsal and MTPJ.

MATERIALS AND METHODS

Dynamic simulations of the stance phase of walking were created by loading 5 non-embalmed, non-paired cadaver lower extremities (2 male, 3 female; mean age, 69; range, 56 to 75) in the Robotic Dynamic Activity Simulator (RDAS). The RDAS recreates lower leg motion and muscle activity based on kinematic and electromyographic data of healthy subjects. FHL tendon forces and excursions were measured for the entire stance phase of gait. Bone strains in the mid-shaft of the first metatarsal were recorded and used to derive the in situ forces and moments imposed on the metatarsal and the hallux MTPJ.

RESULTS

Under force-feedback control, FHL excursion averaged 6.57 (+/-3.13) mm during gait. When the FHL was held 2-, 4-, and 6-mm proximal to the mid-point of normal excursion to simulate progressive stenosis, the forces in the FHL tendon, first metatarsal and first MTP joint were progressively, and significantly, increased (p < 0.05).

CONCLUSION

These findings support the hypothesis that progressive fibrosis at the FHL myotendinous junction can cause increased loading of the hallux MTPJ, thereby leading to hallux rigidus.

Endoscopic flexor hallucis longus decompression: a cadaver study

BACKGROUND

New indications for arthroscopy are being considered because arthroscopy limits incision size and potentially decreases operative morbidity. This cadaver study investigated the utility of performing an all-endoscopic flexor hallucis longus (FHL) decompression.

METHODS

Eight fresh-frozen cadaver legs were used. In the simulated prone position with large joint arthroscopic equipment, posterolateral and posteromedial portals were used to perform posterolateral talar process bony excision and FHL sheath debridement and release. We noted the integrity of the sural nerve, FHL tendon, and medial tibial neurovascular bundle. After open dissection, values for sural nerve distance to the posterolateral portal, the amount of FHL sheath released and the proximity of the arthroscopic instrumentation to the medial tibial neurovascular structures were recorded.

RESULTS

Three of eight FHL tendons were injured during the attempted FHL release. Furthermore, no FHL sheath was completely released down to the level of the sustentaculum. Although posterolateral portal placement was on average 12.1 mm from the sural nerve, it was only 6.1 mm from the lateral calcaneal branch of the sural nerve. Moreover, in all cases the medial calcaneal nerve and first branch of the lateral plantar nerve were closely juxtaposed and in some cases adherent to the FHL fibro-osseous sheath.

CONCLUSIONS

Although os trigonum or posterolateral talar process excision was performed without difficulty, endoscopic release of the FHL tendon proved technically demanding with significant risk to the local neurovascular structures. Given the reliability and low morbidity of open techniques, this cadaver study calls into question the clinical use of complete endoscopic FHL release to the level of the sustentaculum. Moreover, hindfoot endoscopic surgery should be performed by surgeons familiar with open posterior ankle anatomy and experienced in hindfoot endoscopy.

Diagnosis and management of the painful ankle/foot part 1: clinical anatomy and pathomechanics

Distinctive anatomical features can be witnessed in the ankle/foot complex, affording specific pathological conditions. Disorders of the ankle/foot complex are multifactoral and features in both the clinical anatomy and biomechanics contribute to the development of ankle/foot pain. The superior tibiofibular, distal tibiofibular, talocrural, subtalar, and midtarsal joint systems must all participate in function of the ankle/foot complex, as each biomechanically contributes to functional movements and clinical disorders witnessed in the lower extremity. A clinician's ability to effectively evaluate, diagnose, and treat the distal lower extremity is largely reliant upon a foundational understanding of the clinical anatomy and biomechanics of this complex complex. Thus, clinicians are encouraged to consider these distinctions when examining and diagnosing disorders of the ankle/foot.

Sonographically guided flexor hallucis longus tendon sheath injection

OBJECTIVE

The purpose of this study was to describe a sonographically guided technique to perform flexor hallucis longus (FHL) tendon sheath injections.

METHODS

Scans were performed with an intermediate-frequency (7.5- to 12-MHz) linear transducer with the scan plane corresponding to the anatomic axial plane and the patients positioned prone. The transducer was placed along the posteromedial ankle with the needle entry point being lateral to the Achilles tendon. A 25-gauge, 1.5-in needle or a 22-gauge spinal needle was positioned directly into the tendon sheath during real-time visualization with injection of a standardized therapeutic mixture (anesthetic and long-acting corticosteroid) at the level of the posterior sulcus for the FHL. Distention of the tendon sheath during real-time visualization was considered a successful injection.

RESULTS

Twenty-four injections in 20 patients (12 female and 8 male; age range, 22-64 years) were performed with this technique. In each case, distention of the FHL tendon sheath was obtained as the desired end point. Apart from minor paresthesias from local anesthesia, no long-term complications from these injections have occurred to date.

CONCLUSIONS

We describe a method to perform sonographically guided injections of the FHL tendon sheath. Sonography provides several distinct advantages as a method to provide guidance for delivery of therapeutic injections. The most important of these is the ability to visualize the needle and make adjustments in real time to ensure that medication is delivered to the appropriate location. Given these advantages, we propose that sonographic guidance provides an excellent alternative in the administration of corticosteroids to the FHL tendon sheath.

Foot and Ankle Injuries in Dance

Although dancers develop overuse injuries common in other athletes, they are also susceptible to unique injuries. This article reviews common foot and ankle problems seen in dancers and provides some basic diagnosis and treatment strategies.

The Flexor Hallucis Longus: Tenographic Technique and Correlation of Imaging Findings with Surgery in 39 Ankles

PURPOSE

To examine the use of tenography for evaluation of the flexor hallucis longus (FHL) sheath.

MATERIALS AND METHODS

Institutional review board approval was waived, patient consent was obtained, and the study was HIPAA compliant. Retrospective review of 192 FHL tenograms and associated surgical records identified 39 ankles in 37 patients (17 male, 20 female; mean age +/- standard deviation, 38 years +/- 13.8; range, 14-68 years) in which both tenography and surgery had been performed. Two radiologists reviewed tenographic findings, including contrast agent extravasation, synovial irregularity, stenosis, fibrous bands, sheath outpouching, extent of opacification, and communications with adjacent structures. Alterations in pain after anesthesia of the tendon sheath were also recorded. Surgical reports were reviewed.

RESULTS

Thirty-four of 39 tenograms were diagnostic. Some extravasation occurred in nine (45%) of 20 injections with an initial injection method and in two (11%) of 19 with a new injection technique. Synovial irregularity was present in all 34 studies (15 mild, 16 moderate, three severe). Stenoses were identified in 23 (68%) of 34 ankles, fibrous bands were seen in 16 (47%) of 34 ankles, and outpouching of the sheath above a stenosis was present in 13 (38%) of 34 ankles. Communication of the FHL sheath with the ankle, flexor digitorum longus, or subtalar joint occurred in half the cases. Most patients with pain reported relief; relief was complete (100% reduction from preprocedural pain) in eight of 27, moderate (50%-90% reduction) in nine of 27, and mild (<50% reduction) in eight of 27 patients.

CONCLUSION

Tenography of the FHL sheath produced diagnostic images in almost all patients and effectively demonstrated abnormalities of the tendon sheath. Pain relief with anesthetic injection helped confirm the FHL sheath as the pain generator.

Tenosynovitis of the flexor hallucis longus: a clinical study of the spectrum of presentation and treatment

BACKGROUND

Symptoms associated with flexor hallucis longus (FHL) pathology can manifest themselves anywhere along its length from the posterior leg to the plantar foot and the hallux. This study describes the spectrum of clinical presentations seen with FHL pathology, illustrates the relevant physical examination findings, and outlines a treatment approach.

MATERIALS

Computerized medical data was prospectively collected on 81 patients treated between January, 1997 and March, 2002. The 55 females and 26 males had an average age of 38.3 years, with a mean follow-up of 21.3 months. Forty-five of 81 had previous therapy that failed, usually for "plantar fasciitis." Twenty-seven were active athletically and 24 related the onset of symptoms to a specific traumatic episode. Pain was located at the posteromedial ankle in 40, plantar heel in 23, plantar midfoot in 22, and multiple locations in 16. All patients had tenderness of the FHL. Restriction of FHL excursion was demonstrated in 30 patients by limited hallux metatarsophalangeal joint dorsiflexion when the ankle was dorsiflexed ("FHL stretch test"). Thirty-four patients had magnetic resonance imaging of the FHL, 28 (82%) of which were positive for synovitis of the FHL. Treatment included an FHL stretching program, short-term immobilization, and operative decompression and synovectomy in patients for whom nonoperative treatment failed.

RESULTS

Of the 58 patients treated nonoperatively, 37 (64%) had successful results. Twenty-three patients had surgery, 20 at the posterior ankle fibro-osseous tunnel, and three in the sesamoid region. All patients treated operatively had successful outcomes. A subset of 10 patients had hallux rigidus symptoms without significant osteophyte formation. All 10 obtained successful results with treatment directed at restoring normal FHL excursion (nine nonoperatively, one by FHL release). This suggests that limited FHL excursion may be an etiology for the development of hallux rigidus.

CONCLUSIONS

Clinical syndromes related to the FHL are more frequent than previously reported. The close relationship of the FHL to commonly injured structures (such as the plantar fascia) contributes to significant delays in effective treatment.

MR imaging of tendon, ligament, and osseous abnormalities of the ankle and hindfoot

This article serves as an overview of the pathologic processes that are seen in the foot and ankle. MRI can play a pivotal role in making precise diagnoses and then guiding treatment decisions. MRI can be extremely helpful in determining response to therapy.

The accessory flexor digitorum longus as a cause of Flexor Hallucis Syndrome

The Flexor Hallucis Syndrome has been associated with ballet and sports activities. It has been thought to represent over use with attendant tenosynovitis of the tendon in the fibro-osseous tunnel extending from the ankle to the midfoot. We report a patient with an accessory flexor digitorum longus who presented with classical clinical features of the syndrome. The patient's disabling symptoms persisted despite a year and a half of nonoperative treatment. They were finally relieved when the accessory muscle was excised. In addition to the previously described clinical features of the Flexor Hallucis Syndrome, the physical exam included abnormal fullness between the Achilles tendon and the tibia. When the ankle was held in dorsiflexion, there was limited dorsiflexion of the lateral toes, which were tethered by the "cork-in-a-bottle" effect of the distal muscle mass of the accessory flexor digitorum longus muscle at the flexor retinaculum and fibro-osseous canal of the flexor hallucis longus. The MRI examination confirmed the presence of an abnormal muscle mass extending distal to the ankle joint with the foot in neutral. The study also demonstrated fluid in the ankle joint and fibro-osseous canal of the flexor hallucis, and marrow edema within the body of the talus consistent with chronic inflammation. Follow-up MRI six months after excision of the muscle revealed some scar formation at the site of the previously excised muscle and complete resolution of the joint effusion, fluid in the tunnel of the flexor hallucis, and marrow edema.