Posterior tibial nerve entrapment at the ankle

Compression of the posterior tibial nerve of the ankle, also known as tarsal tunnel syndrome (TTS), is being seen withincreasing frequency in athletes, particularly runners. For this reason, it behooves the sports medicine professional to be well informed about this condition. TTS is caused by either extrinsic or intrinsic pressure on the posterior tibial nerve or its terminal branches. The syndrome, although analogous to carpal tunnel syndrome, is much less common. The most common symptoms of TTS are numbness and burning pain in the medial heel and foot. The condition is often difficult to differentiate from plantar fasciitis. Electrodiagnostic studies, including nerve conduction studies and electromyography, help confirm the diagnosis. Conservative measures are usually unsuccessful, and surgical decompression of the tarsal tunnel is generally regarded as the treatment of choice.     

MR imaging in tarsal tunnel syndrome.

Magnetic resonance imaging was used to demonstrate the normal anatomy of the tarsal tunnel in two volunteers and to evaluate 33 feet in 27 patients with tarsal tunnel syndrome. The tarsal tunnel is a fibroosseous channel extending from the ankle to the midfoot, through which the medial tendons and the posterior tibial neurovascular bundle pass. Tarsal tunnel syndrome is a compression neuropathy of the posterior tibial nerve or one of its branches and may be caused by a variety of pathologic lesions. Magnetic resonance imaging demonstrated a mass lesion in five feet, dilated veins or varicosities in eight feet, fracture or soft tissue injury in five feet, fibrous scar in two feet, flexor hallucis longus tenosynovitis in six feet, and abductor hallucis muscle hypertrophy in one foot. Six feet were normal on MR imaging. The findings of MR imaging were confirmed in 17 of 19 patients that went to surgery. Magnetic resonance is useful for localizing lesions within the tarsal tunnel and for determining the lesion extent and relationship to the posterior tibial nerve and its branches.     

Nerve entrapment of the foot and ankle in runners

In the 10 years 1972 through 1982, the senior author performed 21 operations on 15 runners with persistent foot and ankle pain. The operative procedures involved decompression of peripheral nerves in the foot and ankle, consisting of release of soft tissues in the tarsal tunnel and foot or removal of abnormal bony excrescences that were irritating these nerves. All 15 runners had good to excellent results and all returned to their preinjury running status, including the competitive athletes. Foot and ankle pain is best treated conservatively, but when signs and symptoms culled from a careful history and physical examination reflect a nerve entrapment syndrome, surgical intervention has its place in the armamentarium of the surgeon.     

改良微创胫后神经减压术治疗跗管综合征

目的探讨改良微创胫后神经减压手术（显微镜结合关节镜技术）治疗跗管综合征。方法采用独创的单切口微创胫后神经减压手术对跗管综合征患者进行手术治疗,术中采用与屈肌支持带和拇展肌之间的平行于屈肌支持带的直切口,在显微镜和关节镜下同时对胫后神经主干及其分支进行满意松解,同时显著减轻了手术损伤。结果患者足底疼痛麻木症状均明显缓解120侧,缓解14侧患肢,麻木缓解28侧,缓解程度达85%以上,胫神经传导速度明显上升。结论微创胫后神经减压手术为跗管综合征的治疗提供了一条有效的新途径。     

MR imaging of flexor digitorum accessorius longus

Objective The flexor digitorum accessorius longus muscle (FDAL), an anomalous muscle about the ankle, has recently been implicated in tarsal tunnel syndrome. The purpose of this study is to document the prevalence of the FDAL, its MR appearance and its relation to the neurovascular bundle in the tarsal tunnel. Design and patients The prevalence of the FDAL was determined from 100 ankle MR examinations in asymptomatic individuals. The appearance of the FDAL was summarized from 20 examples of FDAL: six gathered from the asymptomatic group and 14 acquired from a group of randomly collected cases of patients with ankle complaints. Results The prevalence of the FDAL was 6%, calculated from the group of 100 asymptomatic individuals. Possessing a dominant fleshy component in the tarsal tunnel, the FDAL accompanies the posterior neurovascular bundle as it descends the ankle. Conclusion The FDAL is encountered in 6% of asymptomatic individuals. Its prominent fleshy component in the tarsal tunnel and its close proximity to the posterior tibial neurovascular bundle readily differentiate the FDAL from other medial anomalous muscles on MR imaging. Received: 29 September 1998 Revision requested: 6 November 1998 Revision received: 30 November 1998 Accepted: 30 November 1998     

MR imaging of the tarsal tunnel and related spaces: normal and abnormal findings with anatomic correlation

The tarsal tunnel syndrome may be caused by extrinsic or intrinsic pressure on the posterior tibial nerve or its terminal branches. The specific symptoms depend on the extent of nerve involvement, and compression distal or proximal to the tarsal tunnel may result in variants of the syndrome. To define better the capability of MR imaging for evaluating this entity, we performed MR imaging on three normal subjects and correlated the images with cryomicrotome sections. Six patients with symptoms suggestive of tarsal tunnel syndrome also were studied with MR. In all normal subjects, MR images showed the flexor retinaculum and the structures passing deep to the retinaculum: the tibialis posterior tendon, flexor digitorum longus tendon, flexor hallucis longus tendon, and the posterior tibial neurovascular bundle. The medial calcaneal sensory branch(es) and the medial and lateral plantar nerves also were delineated. Mechanical causes of compression were shown in all six symptomatic patients. The pathologic entities included two neurilemomas, tenosynovitis involving all three tendons, a ganglion cyst arising from the flexor hallucis longus tendon sheath, posttraumatic fibrosis, and post-traumatic fibrosis with associated posttraumatic neuroma. The MR findings were confirmed surgically in five cases. MR imaging can accurately depict the contents of the tarsal tunnel and the courses of the terminal branches of the posterior tibial nerve. In our small series, MR imaging accurately showed the lesions responsible for tarsal tunnel syndrome.     

Preventing Heat Injury in Sports

Most of the common foot problems that bother active middle-aged people are self-limiting and easily treated if detected early. Reviewed here are the causes, symptoms, diagnosis, and treatment of hallux valgus and rigidus, lesser-toe deformities, corns, Morton's neuroma, metatarsal stress fractures, plantar fasciitis, posterior tibialis tenosynovitis and rupture, acquired pes planus, tarsal tunnel syndrome, and foot problems related to rheumatoid arthritis and diabetes. In most cases, conservative treatment will enable patients to return to activity relatively quickly.     

Disfunción del tendón tibial posterior: ¿qué otras estructuras están implicadas en el desarrollo del pie plano adquirido del adulto?

Objective

To evaluate the association of posterior tibial tendon dysfunction and lesions of diverse ankle structures diagnosed at MRI with radiologic signs of flat foot.

Material and methods

We retrospectively compared 29 patients that had posterior tibial tendon dysfunction (all 29 studied with MRI and 21 also studied with weight-bearing plain-film X-rays) with a control group of 28 patients randomly selected from among all patients who underwent MRI and weight-bearing plain-film X-rays for other ankle problems.In the MRI studies, we analyzed whether a calcaneal spur, talar beak, plantar fasciitis, calcaneal bone edema, Achilles’ tendinopathy, spring ligament injury, tarsal sinus disease, and tarsal coalition were present. In the weight-bearing plain-film X-rays, we analyzed the angle of Costa-Bertani and radiologic signs of flat foot. To analyze the differences between groups, we used Fisher's exact test for the MRI findings and for the presence of flat foot and analysis of variance for the angle of Costa-Bertani.

Results

Calcaneal spurs, talar beaks, tarsal sinus disease, and spring ligament injury were significantly more common in the group with posterior tibial tendon dysfunction (P<.05). Radiologic signs of flat foot and anomalous values for the angle of Costa-Bertani were also significantly more common in the group with posterior tibial tendon dysfunction (P<.001).

Conclusion

We corroborate the association between posterior tibial tendon dysfunction and lesions to the structures analyzed and radiologic signs of flat foot. Knowledge of this association can be useful in reaching an accurate diagnosis.     

Tarsal tunnel syndrome in athletes

BACKGROUND: The details of the occurrence of tarsal tunnel syndrome in athletes have not been well documented in the literature, and more data on tarsal tunnel syndrome related to sporting activity are necessary to enable better recognition of this condition. HYPOTHESIS: Sporting activities make athletes vulnerable to the occurrence of tarsal tunnel syndrome under specific conditions. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Between 1986 and 2002, 18 patients with tarsal tunnel syndrome related to sporting activities were surgically treated, of whom 15 patients (21 feet; mean age, 17.8 years) were competitive athletes and 3 were recreational sports amateurs (4 feet; mean age, 52.7 years). To assess the role of physical factors and sporting activities in making athletes vulnerable to the occurrence of tarsal tunnel syndrome, the authors reviewed the medical charts and evaluated the results of treatment. The mean duration of follow-up was 58.6 months. RESULTS: Activities that triggered tarsal tunnel syndrome were those that applied a heavy burden on the ankle joint such as sprinting, jumping, and performing ashibarai in judo under specific physical conditions. Predisposing underlying physical factors were flatfoot deformity and an existence of talocalcaneal coalition, accessory muscles, and bony fragments around the tarsal tunnel. The majority of patients were able to return to the same sport after treatment. CONCLUSION: Tarsal tunnel syndrome occurs in athletes involved in strenuous sporting activities, especially when predisposing physical factors are present.     

MRI of the foot and ankle: prevalence and distribution of occult and palpable ganglia

The purpose of this study was to evaluate the prevalence and anatomic distribution of occult and palpable ganglia of the foot and ankle as seen by MRI. Within a 7-year period MRI of the ankle was performed on 2813 patients, and MRI of the foot on 2277 patients using a 1.5T magnet. In all, 167 ganglia in 155 patients were detected. MR images of these patients were reviewed retrospectively by two observers with regard to prevalence, imaging characteristics, and exact anatomic location of ganglia. Clinical findings and (when available) surgical reports were also reviewed. One hundred fifty-seven ganglia in 145 patients were present on MR images of the ankle, and 10 ganglia in 10 patients on MR images of the foot, resulting in a prevalence of 5.6% (157/2813) in the ankle, and a prevalence of 0.4% (10/2277) in the foot. The most common location was the tarsal sinus or tarsal canal (57/167 ganglia [34.1%]). However, only four of these (7%) were palpable as a soft-tissue mass. The second most common location was around the Lisfranc joint (23/167 [13.8%]), of which 11/23 [47.8%] were clinically palpable. Palpable ganglia were statistically larger in size than occult ganglia measured in any of three diameters (P = 0.01-0.002). In addition, ganglia of the foot and ankle represented 42% of all clinically suspected soft-tissue masses. Ganglia in the foot and ankle are an infrequent finding on routine MRI of the foot and ankle. When they occur, these ganglia are most frequently located in the tarsal sinus and tarsal canal, where they are occult to clinical palpation. If ganglia are clinically palpable, they are most commonly located around the Lisfranc joint. In addition, palpable ganglia are larger than occult ganglia.     

Imaging of foot and ankle nerve entrapment syndromes: from well-demonstrated to unfamiliar sites.

Nerve entrapment at the foot and ankle involves thin and complex anatomic structures and is underdiagnosed because clinical symptoms and electrophysiologic findings may not contribute to the diagnosis. Nerve entrapment can be secondary to acute trauma or repetitive microtrauma. The latter often results from intensive sports-related activity, inappropriate footwear, or internal foot derangement. Various lesions that occur in fibro-osseous tunnels can cause nerve compression (eg, ganglion cysts, varicosities, bone and joint abnormalities, tumors, tenosynovitis, supernumerary or hypertrophic muscles). Accurate nerve examination must be performed, particularly in patients with atypical ankle pain, to detect focal tenderness or paresthesia. Ultrasonography is useful in this setting because it yields both clinical and morphologic findings. High-resolution magnetic resonance imaging provides accurate delineation of the nervous system anatomy. Furthermore, technologic developments in the field of radiology are making it possible to obtain clearer, more accurate images. Radiologists must be aware of the main nerve entrapment syndromes at the foot and ankle and be able to perform accurate nerve examinations with different imaging modalities in patients with foot and ankle pain.     

Ganglia of the tarsal sinus: MR imaging features and clinical findings

Purpose

To analyze MR imaging and clinical findings associated with ganglia of the tarsal sinus.

Materials and methods

In a record search, ganglia of the tarsal sinus were retrospectively identified in 26 patients (mean age 48 ± 16 years), who underwent MR imaging for chronic ankle pain. Images were reviewed by two radiologists in consensus for size and location of ganglia, lesions of ligaments of the ankle and the tarsal sinus, tendon abnormalities, osteoarthritis, osseous erosions and bone marrow abnormalities. Medical records were reviewed for patient history and clinical findings.

Results

Ganglia were associated with the interosseus ligament in 81%, the cervical ligament in 31% and the retinacula in 46% of cases. Signal alterations suggesting degeneration were found in 85%, 50% and 63% in case of the interosseus ligament, the cervical ligament and the retinacula, respectively. Scarring of the anterior talofibular ligament and the fibulocalcaneal ligament was found in 68% and 72% of the patients, respectively, while only 27% of the patients recalled ankle sprains. Ganglia at the retinacula were highly associated with synovitis and tendinosis of the posterior tibial tendon (p < 0.05).

Conclusion

All patients with ganglia in the tarsal sinus presented with another pathology at the ankle, suggesting that degeneration of the tarsal sinus may be a secondary phenomenon, due to pathologic biomechanics at another site of the hind foot. Thus, in patients with degenerative changes of the tarsal sinus, one should be alerted and search for underlying pathology, which may be injury of the lateral collateral ligaments in up to 70%.     

职业足球运动员足踝关节无症状慢性损伤MR影像特点的初步研究

目的分析职业足球运动员足踝关节无症状慢性损伤的MR影像特点。方法募集2017年3月—5月间18名天津当地足球俱乐部的现役运动员作为研究对象,均可正常参加训练和比赛,且至本次检查6个月内均无足踝关节不适症状。采用3.0 T MRI进行踝关节扫描,观察每位运动员踝关节的骨质、韧带、肌腱情况。采用Fisher精确检验比较触球足和立足足踝关节不同结构损伤情况的发生率。结果骨质损伤主要表现为骨髓水肿、囊变、关节游离体形成及不规则骨突形成。其中骨髓水肿共12例17个踝关节(触球足10个,立足7个);3例3个踝关节(触球足1个,立足2个)可见关节游离体形成;7例7个踝关节(触球足5个,立足2个)出现距后三角骨。2例2个踝关节(触球足、立足各1个)可见距骨后突。触球足组和立足组间骨质损伤发生率差异均无统计学意义(均P0.05)。内侧三角韧带损伤5例共5个踝关节(触球足2个,立足3个);距腓前韧带损伤17例共25个踝关节(触球足8个,立足17个);跟腓韧带损伤9例12个踝关节(触球足5个,立足7个);下胫腓前韧带损伤1例1个踝关节(触球足);未见距腓后韧带、下胫腓后韧带损伤病例。立足组距腓前韧带损伤发生率高于触球足组(P=0.003)。其余韧带损伤发生率,2组间差异无统计学意义(均P0.05)。肌腱损伤主要表现为腱鞘积液,踇长屈肌腱腱鞘积液17例26个踝关节(触球足12个,立足14个);趾长屈肌腱腱鞘积液8例10个踝关节(触球足5个,立足5个);胫骨后肌腱腱鞘积液9例12个踝关节(触球足5个,立足7个);腓骨长短肌腱腱鞘积液4例4个踝关节(触球足2个,立足2个);趾长伸肌腱腱鞘积液2例2个踝关节(触球足1个,立足1个)。未发现胫骨前肌腱、踇长伸肌腱腱鞘积液及跟腱周围积液。触球足组和立足组间腱鞘积液发生率差异均无统计学意义(均P0.05)。结论职业足球运动员艰苦的训练和比赛容易造成踝关节反复创伤,主要特点为骨髓水肿、囊变,韧带损伤及腱鞘积液。由于双足在足球运动中功能不同,触球足和立足损伤特点亦不同。     

Medial subtalar arthroscopy: a cadaveric study of the tarsal canal portal

Purpose

To study the safety of the tarsal canal portal in medial subtalar arthroscopy.

Methods

Twenty-three fresh frozen foot and ankle specimens were divided into two groups with different orientation of the portal tract. Three types of tarsal canal portals were identified. The relationships of the metal rod and the flexor digitorum longus tendon and the posterior neurovascular bundle were studied.

Result

In group A, a type 1 tarsal canal portal tract was established in seven specimens, a type 2 portal tract in three specimens, and a type 3 portal tract in two specimens. In group B, a type 1 portal tract was established in ten specimens and a type 2 portal tract in one specimen. No type 3 portal tract was established in group B. There was no statistical significance demonstrated for establishment of a type 1 portal tract and “non type 1” (type 2 or 3) portal tract in group A and group B. The average shortest distance between the rod and the posterior tibial neurovascular bundle was 7 mm in group A and 9 mm in group B.

Conclusions

This study provides the anatomic basis for the establishment of the tarsal canal portal. There is a risk of injury to the flexor digitorum longus tendon and the posterior tibial neurovascular bundle with the tarsal canal portal, and it should be used with great caution.     

Nerve disorders in dancers

Dancers are required to perform at the extreme of physiologic and functional limits. Under such conditions, peripheral nerves are prone to compression. Entrapment neuropathies in dance can be related to the sciatic nerve or from a radiculopathy related to posture or a hyperlordosis. The most reproducible and reliable method of diagnosis is a careful history and clinical examination. This article reviews several nerve disorders encountered in dancers, including interdigital neuromas, tarsal tunnel syndrome, medial hallucal nerve compression, anterior tarsal tunnel syndrome, superficial and deep peroneal nerve entrapment, and sural nerve entrapment.     

Anatomical variations within the deep posterior compartment of the leg and important clinical consequences.

The management of musculoskeletal conditions makes up a large part of a sports medicine practitioner's practice. A thorough knowledge of anatomy is an essential component of the armament necessary to decipher the large number of potential conditions that may confront these practitioners. To cloud the issue further, anatomical variations may be present, such as supernumerary muscles, thickened fascial bands or variant courses of nerves and blood vessels, which can themselves manifest as acute or chronic conditions that lead to significant morbidity or limitation of activity. There are a number of contentious areas within the literature surrounding the anatomy of the leg, particularly involving the deep posterior compartment. Conditions such as chronic exertional compartment syndrome, tibial periostitis (shin splints), peripheral nerve entrapment and tarsal tunnel syndrome may all be affected by subtle anatomical variations. This paper primarily focuses on the deep posterior compartment of the leg and uses the gross dissection of cadaveric specimens to describe definitively the anatomy of the deep posterior compartment. Variant fascial attachments of flexor digitorum longus are documented and potential clinical sequelae such as chronic exertional compartment syndrome and tarsal tunnel syndrome are discussed.     

改良胫后肌移位术治疗腓总神经损伤后足下垂及内翻畸形

目的 探讨改良胫后肌移位术治疗腓总神经损伤所致足下垂及内翻畸形的早期疗效.方法 采用回顾性病例系列研究分析2017年12月至2019年10月北京积水潭医院收治的6例腓总神经麻痹性足下垂及内翻患者的临床资料,其中男4例,女2例;年龄33～48岁[(39.5 ±6.0)岁].左侧4例,右侧2例.患者均行胫后肌移位术,通过异...     

Posterior compartment fractures of the ankle. A commonly missed athletic injury

This paper brings to the reader's attention an injury and symptom complex resulting from an ankle sprain during athletic competition. Twenty patients were reviewed and followed over a 3 1/2 year period of time. Three patients presented acutely and 17 patients presented after an extended period of time with residual ankle morbidity. Common to this group of patients was a history of having sustained an ankle sprain, most commonly secondary to a forced plantar flexion type injury. Subsequent disability was generally posterior and postero-lateral ankle pain associated with running and/or jumping. Clinical examination invariably demonstrated posterior ankle pain, particularly with forced plantar flexion of the foot. All patients demonstrated bony changes in the area of the posterior talus and/or tibia by x-ray, and all patients had a positive technetium bone scan of the posterior ankle area. If the injury is diagnosed acutely, cast immobilization is the treatment of choice. If diagnosed late, it is suggested that for those patients who fail conservative treatment, surgical removal of the fragment is best. The majority of patients in this study required surgical extirpation of the posterior talus bony fragment in order to relieve symptoms and return to full sports competition.     

Injuries to dancers. Prevalence, treatment and prevention

Studies from the USA and UK indicate that the back, neck and shoulder and the lower limb (particularly the hip, knee, ankle and foot) are the most frequent sites of injury among dancers. Most injuries are soft tissue injuries. Most dancers experience injuries at some time and about half have chronic injuries. Shoulder injuries appear to be caused by frequent or unaccustomed lifting, and are treated by rest and oral anti-inflammatory medication. Back injuries include sprains, prolapsed or herniated intervertebral discs, and spondylolytic stress fractures. Several risk factors, especially training error, have been identified for overuse injuries. Hip injuries include degenerative changes and osteoarthritis, stress fractures, bursitis and damage to the sciatic nerve. The most common foot injury is an anterior lateral ligament sprain, which may lead to permanent instability in the ankle. More soundly based research into the prevalence, diagnosis and treatment of injuries is needed.