Diagnosis Of Tarsal Tunnel Syndrome Research Articles

Cut-off value for a normal posterior tibial nerve to diagnose tarsal tunnel syndrome amongst people of different race in Pretoria, South Africa.

Posterior tibial nerve (PTN) cross-sectional area (CSA) reference values for the diagnosis of tarsal tunnel syndrome (TTS) using ultrasound imaging exist in several countries but not in South Africa (SA). Therefore, the objective was to measure the CSA reference values for PTN in SA. Ultrasound CSA measurements of PTN in both ankles on 112 participants were performed, the mean measurement was recorded, and the effect of race, age, gender, and body mass index (BMI) were recorded. In this study, the primary variables age and BMI affect the CSA measurement of the PTN. A positive correlation was found between PTN asymptomatic size and age (r = 0.196, P < 0.05), size and BMI (r = 0.200, P < 0.05). Age (categories) had a mean value of 3.17 for the age group 36-45 years (95% confidence interval (CI) 2.9-3.4). The mean BMI was 30.0 kg/m2 (CI 28.57-31.08). As for the asymptomatic PTN, a mean CSA reference value of 0.10 cm2 was obtained. With increase in age and BMI, a greater PTN measurement will occur. Race appears to be a contributing factor, but further research is needed in this regard. The reference CSA value for normal PTN should be set at 0.10 cm2 for all racial groups for a basic musculoskeletal ultrasound exam protocol in South Africa.

Lessons in clinical reasoning - pitfalls, myths, and pearls: a case of tarsal tunnel syndrome caused by an intraneural ganglion cyst.

Intraneural ganglionic cysts are non-neoplastic cysts that can cause signs and symptoms of peripheral neuropathy. However, the scarcity of such cases can lead to cognitive biases. Early surgical exploration of space occupying lesions plays an important role in identification and improving the outcomes for intraneural ganglionic cysts. This patient presented with loss of sensation on the right sole with tingling numbness for six months. A diagnosis of tarsal tunnel syndrome was made. Nerve conduction study revealed that the mixed nerve action potential (NAP) was absent in the right medial and lateral plantar nerves. The magnetic resonance imaging (MRI) found a cystic lesion measuring 1.4×1.8×3.8 cm as the presumed cause of the neuropathy. Surgical exploration revealed a ganglionic cyst traversing towards the flexor retinaculum with baby cysts. The latter finding came as a surprise to the treating surgeon and was confirmed to be an intraneural ganglionic cyst based on the histopathology report. Through integrated commentary by a case discussant and reflection by an orthopedician, this case highlights the significance of the availability heuristic, confirmation bias, and anchoring bias in a case of rare disease. Despite diagnostic delays, a medically knowledgeable patient's involvement in their own care lead to a more positive outcome. A fish-bone diagram is provided to visually demonstrate the major factors that contributed to the diagnostic delay. Finally, this case provides clinical teaching points in addition to a pitfall, myth, and pearl related to availability heuristic and the sunk cost fallacy.

The role of ultrasound-guided perineural injection of the tibial nerve with a sub-anesthetic dosage of lidocaine for the diagnosis of tarsal tunnel syndrome.

Tarsal tunnel syndrome (TTS) involves entrapment of the tibial nerve at the medial ankle beneath the flexor retinaculum and its branches, the medial and lateral plantar nerves, as they course through the porta pedis formed by the deep fascia of the abductor hallucis muscle. TTS is likely underdiagnosed, because diagnosis is based on clinical evaluation and history of present illness. The ultrasound-guided lidocaine infiltration test (USLIT) is a simple approach that may aid in the diagnosis of TTS and predict the response to neurolysis of the tibial nerve and its branches. Traditional electrophysiological testing cannot confirm the diagnosis and only adds to other findings. We performed a prospective study of 61 patients (23 men and 38 women) with a mean age of 51 (29-78) years who were diagnosed with idiopathic TTS using the ultrasound guided near-nerve needle sensory technique (USG-NNNS). Patients subsequently underwent USLIT of the tibial nerve to assess the effect on pain reduction and neurophysiological changes. USLIT led to an improvement in symptoms and nerve conduction velocity. The objective improvement in nerve conduction velocity can be used to document the pre-operative functional capacity of the nerve. USLIT may also be used as a possible quantitative indicator of whether the nerve has the potential to improve in neurophysiological terms and ultimately inform prognosis after surgical decompression. USLIT is a simple technique with potential predictive value that can help the clinician to confirm the diagnosis of TTS before surgical decompression.

Novel electrodiagnostic provocative techniques for the diagnosis of suspected tarsal tunnel syndrome

BackgroundElectrodiagnostic tests (EDXTs) have been considered the gold standard method for the diagnosis of tarsal tunnel syndrome (TTS); however, definitive tests has not yet been discovered. Our aim was to develop new nerve conduction provocative techniques in the double and single leg stance as well as combined ankle dorsiflexion with foot eversion accompanied by compression for the diagnosis of suspected TTS.ResultsRoutine combined nerve conduction studies (NCSs) using medial plantar (MP) and lateral plantar (LP) nerves had a 60.9% sensitivity for the diagnosis of TTS. The diagnostic sensitivity increased when combining the three novel tests reaching 82.6% and 78.3% using either MP or LP NCSs respectively. The diagnostic sensitivity further increased to reach 100% when combining the MP and LP novel NCSs considering either the latency or amplitude.ConclusionThe full diagnostic sensitivity for TTS reached 100% by using a battery of novel tests. The proposed diagnostic workup by this study recommends using these biomechanically challenging tests to complete the diagnostic battery of tests especially in symptomatic patients with negative routine tests.

A Rare Case of Flexor Digitorum Accessorius Longus Muscle Presenting as Tarsal Tunnel Syndrome.

Tarsal tunnel syndrome (TTS) is a relatively uncommon nerve entrapment neuropathy. Many pathologies are reported as possible causes for TTS. The diagnosis of TTS can be difficult and often missed. We present a rare case of TTS due to an accessory flexor digitorum longus muscle. Together with a high index of suspicion, MRI is the investigation of choice in making the diagnosis. These patients are best managed with excision or transposition of the flexor digitorum accessorius longus (FDAL) and neurolysis of the posterior tibial nerve and its branches.

Translated article] Tarsal tunnel syndrome: Clinical-imaging analysis of a case series

BackgroundRetrospective review of patients with a diagnosis of Tarsal Tunnel Syndrome (TTS) treated surgically. MethodsRetrospective series of patients with diagnosis of TTS operated between 2005 and 2020 in the same center. Variables such as age, sex, side, affected nerve or branch, classification, type of imaging study, biopsy result, infection rate, recurrence rate, sequelae, among others, were analyzed. ResultsWe included 8 men and 2 women with an average age of 47 years (range 34−67) and an average follow-up of 62.2 months (range 2–149). All cases were related to intrinsic compression. The most frequent cause was the presence of cyst (40%) followed by perineural adhesions (20%). The posterior tibial nerve was the most affected (50%) and 30% the medial plantar branch. Ultrasound (70%) and MRI (50%) were the most requested studies. There were no cases of postoperative infection. There were 3 patients who presented recurrence of the lesion requiring a new surgery. ConclusionsTTS is a neuropathy involving the posterior tibial nerve or some of its branches. In general, it is caused by compression of the nerve by different structures such as accessory muscles and ganglions, among others. The diagnosis is eminently clinical, supported by imaging studies. Surgical treatment presents better results when the cause is an intrinsic compression, although variable recurrence rates are described.

Ultrasound-Guided Near-Nerve Needle Sensory Technique for the Diagnosis of Tarsal Tunnel Syndrome.

Background: Tarsal tunnel syndrome (TTS) is one of the most common entrapment syndromes. Although diagnosis is supported by imaging tests, it has so far been based on clinical findings. Neurophysiological tests are not effective for providing an accurate diagnosis. The objective of this study was to analyze the efficacy of the ultrasound-guided near-nerve needle sensory technique (USG-NNNS) for the diagnosis of TTS Methods: The study population comprised 40 patients referred for a neurophysiological study owing to clinical suspicion of TTS. Routine neurophysiological tests were performed and compared with the results of USG-NNNS. Results: The diagnosis of TTS was achieved in 90% of cases. We found significant differences between lateral plantar sensory recordings with surface electrodes and USG-NNNS techniques for amplitude, nerve conduction velocity (NCV), and duration. As for the medial plantar sensory recordings, differences were found only for duration. No responses were obtained with surface electrode studies in 64.8% of cases. In addition, we observed normal sensory NCV with surface electrodes in 20 patients, although this decreased when the NNNS technique was used. Conclusions: This is the first report of the efficacy of the USG-NNNS technique for confirming the diagnosis of TTS.

Síndrome del túnel del tarso: análisis clínico-imagenológico de una serie de casos

BackgroundRetrospective review of patients with a diagnosis of Tarsal Tunnel Syndrome (TTS) treated surgically. MethodsRetrospective series of patients with diagnosis of TTS operated between 2005 and 2020 in the same center. Variables such as age, sex, side, affected nerve or branch, classification, type of imaging study, biopsy result, infection rate, recurrence rate, sequelae, among others, were analyzed. ResultsWe included 8 men and 2 women with an average age of 47 years (range 34-67) and an average follow-up of 62.2 months (range 2-149). All cases were related to intrinsic compression. The most frequent cause was the presence of cyst (40%) followed by perineural adhesions (20%). The Posterior Tibial Nerve was the most affected (50%) and 30% the Medial Plantar Branch. Ultrasound (70%) and MRI (50%) were the most requested studies. There were no cases of postoperative infection. There were 3 patients who presented recurrence of the lesion requiring a new surgery. ConclusionsTTS is a neuropathy involving the posterior tibial nerve or some of its branches. In general, it is caused by compression of the nerve by different structures such as accessory muscles and ganglions, among others. The diagnosis is eminently clinical, supported by imaging studies. Surgical treatment presents better results when the cause is an intrinsic compression, although variable recurrence rates are described.

Comparative Post-operative Outcomes between Positive and Negative Electromyography (EMG) in Patient with Tunnel Syndrome: A Retrospective Study

Category:OtherIntroduction/Purpose:Tarsal tunnel syndrome can be established using combination of physical examination and electrodiagnostic study including tenderness along tibial nerve in tarsal tunnel area, Tinel sign positive, and positive EMG. However, it has been reported that the sensitivity of the electrodiagnostic study is only 52% for diagnosis of tarsal tunnel syndrome. Therefore, although EMG is negative, some surgeons prefer to make a diagnosis base on physical examination. Conservative treatment is the first line of treatment and when this fails, surgical treatment is indicated. The purpose of this study was to compare post-operative outcomes following tarsal tunnel release in patients who had tarsal tunnel syndrome with positive and negative electrodiagnostic study.Methods:The retrospective chart review of 34 consecutive patients who had underwent tarsal tunnel release between 2015 and 2019 were enrolled in this study. The patients were classified into 2 groups based on results of electrodiagnostic study (negative EMG 15 patients and positive EMG 18 patients). All patients had been treated with conservative treatment for at least 6 months including modified inserted and shoe wear, activities modifications, NSAIDs, and gabapentin. The primary outcome was pain level using Visual Analogue Scale (VAS) while the secondary outcomes were SF-36, FAAM, recovery times (time to return to ADL, work, and sports), and complications. A paired sample t-test was used to assess statistical differences between pre- and post- operative functional outcomes (VAS, SF-36, and FAAM) in the same group of both negative and positive EMG while an independent t-test was used to compare functional outcomes (VAS, SF-36, and FAAM) between the negative and positive EMG.Results:There were 33 patients (15 male and 18 female) with mean age of 49.2 years (range, 25-71 years), mean BMI of 24.7 kg/m2 (range, 17.6-33.2 kg/m2), and mean follow-up of 17.9 months (range, 12-36 months). The mean duration of symptom before the surgery was 8.7 months and 10.2 months for EMG negative and positive respectively. Both groups demonstrated significant improvement of all functional outcomes (FAAM, SF-36, and VAS (p<0.001 all)) compared to pre-operative status; however, there was no significant difference between the two groups, (p>0.05 all). The recovery time were to return to daily activities (3.5 vs 3.6 weeks), time to return to work (5.4 vs 5.6 weeks), and time to return to sport (16.4 vs 17.1 weeks). There were no complications in both groupsConclusion:Tarsal tunnel release demonstrated significantly improvement of functional outcomes in both negative and positive electrodiagnostic study in patients as measured with VAS, SF-36, and FAAM. However, negative EMG did not demonstrate negative impact on functional outcomes after tarsal tunnel release. When clinical and physical examination suspects tarsal tunnel syndrome, tarsal tunnel release should be considered even thought there is negative on electrodiagnostic study.

Can the axial cross-sectional area of the tibial nerve be used to diagnose tarsal tunnel syndrome? An ultrasonography study

IntroductionThe axial cross-sectional area (CSA) of the tibial nerve can be measured with ultrasonography. In patients who have posteromedial tarsal tunnel syndrome (TTS), there is little information on the nerve's CSA even though this information could be useful for determining whether the nerve is damaged. This led us to carry out a case-control study in which the tibial nerve's axial CSA was measured in healthy patients and in patients with TTS. HypothesisThe tibial nerve's axial CSA can be used as a diagnostic criterion for TTS. MethodsTwenty-three patients (27 feet) (11 men, 12 women, mean age=54±14 years), who had clinical and electroneuromyography signs of TTS, were compared to 21 healthy adults (8 men, 13 women, mean age 39±10 years). An ultrasonography examination was carried out to look for a source of nerve compression, then the axial CSA of the tibial nerve was measured 10cm above the tarsal tunnel (lCSA) and inside the tunnel itself (ttCSA). The difference between the two measurements was then calculated: ΔCSA=ttCSA–lCSA. The data were analysed using correlation tests and non-parametric tests, a multivariate linear regression and ROC tests. ResultsA compressive cause was found by ultrasonography in 13 patients. The mean values of ttCSA and ΔCSA were 20.1±8.8 mm2 [6–42] vs. 10.3±2.3 mm2 [8–14] (p=0.0001) and 9.8±6.7 mm2 [0–29] vs. −0.2±1.8 mm2 [−3–4] (p<0.0001) in the patients and the controls, respectively. The differences in ΔCSA remained significant in the multivariate analysis after adjusting for age and weight. The best threshold for ttCSA in the TTS group was 15 mm2 with 74% sensitivity and 100% specificity. The best threshold for ΔCSA was 5mm2 with 81% sensitivity and 100% specificity. DiscussionThe difference in the measured axial CSA of the tibial nerve by ultrasonography between the posteromedial tarsal tunnel and 10cm above the tunnel is a key data point for the diagnosis of tarsal tunnel syndrome with and without compressive etiology. Level of evidenceIII, diagnostic case-control study.

Tarsal tunnel syndrome: Anatomical facts and clinical implications

Introduction: Tarsal tunnel syndrome (TTS) associates with the posterior tibial nerve (PTN) entrapment at the medial side of the ankle. TTS is a major cause of heel pain. The diagnosis and treatments have several techniques. For accurate diagnosis and effective treatment, the surgeons need to have detailed anatomical knowledge of the arrangement of PTN. The aim of this present study is to describe anatomical aspects and TTS including its etiology, diagnosis, and treatments. Material and Methods: This literature review was done by searching the data from the following databases such as PubMed, Google Scholar, Springer, Elsevier (ScienceDirect), and book chapter. Results: This literature review showed anatomical variations of the PTN and its branches that used the malleolar-calcaneal axis for measurement of branching point. Moreover, these studies showed the origin and the number of branches. The diagnosis of TTS can be used numerous techniques such as neurophysiology, electromyography (EMG), ultrasound scanning (US), and magnetic resonance imaging. The treatment for TTS includes conservative approach, open surgery, and endoscopic procedures. Discussion and Conclusion: The anatomical knowledge of the neurovascular structures at the medial side of the ankle is not only considered for diagnostic purposes but also it ensures safe and effective operative procedures. This literature review will be beneficial for academics and clinicians.

O-2-31. The usefulness of electrophysiological examinations in the diagnosis of tarsal tunnel syndrome

TTS is usually diagnosed based on clinical symptoms and signs, and electrodiagnostic (EDx) tests, typically nerve conduction studies. We aimed to present a case series of TTS and investigate the diagnostic role of EDx. We searched our EMG database from 2008 to 2016 with the keyword of TTS, and retrospectively reviewed clinical and EMG records of extracted patients. The entry criteria were: (1) clinical diagnosis of TTS by the referring doctor, (2) numbness of sole and a positve Tinel’s sign at the ankle, and (3) both the tibial motor conduction study (MCS) and plantar sensory conduction study (SCS) were conducted. Enrolled were 12 patients (20–82 years, 9 men and 3 women). Some EDx tests were abnormal in 8 patients. Plantar SCS was abnormal on the affected side in 5 patients. In 2 of them, tibial MCS showed a bilobed compound muscle action potential (CMAP) indicating the isolated delay of the medial plantar nerve. One patient had abnormal F wave, and 2 patients was shown denervation potentials in the FHB muscle. TTS is in general difficult to confirm electrodiagnostically, although this study supported the role of EDx. Bilobed tibial CMAP may be a previously undescribed sign of TTS.

Magnetic Resonance Imaging Conditions for Imaging of the Tarsal Tunnel

Tarsal tunnel syndrome(TTS)is an entrapment neuropathy of the posterior tibial nerve within the tarsal tunnel below the medial malleolus. An accurate diagnosis is difficult, and TTS is usually diagnosed from clinical symptoms due to the lack of accurate diagnostic tools. We aimed to standardize the diagnosis of TTS using MRI, and report the MRI conditions for clear visualization of the tarsal tunnel. We investigated which sequences and MRI conditions would be appropriate for the imaging of the tarsal tunnel in a healthy volunteer. As in routine brain MRI, the imaging time was within 15 minutes. We also performed an MRI study of the tarsal tunnel in two patients with TTS. Axial images obtained by fat-suppression 3-dimensional T2^*-weighted imaging(3D-T2^*WI)are the most useful for visualization of the tarsal tunnel. The axial images obtained by T2-weighted imaging(T2WI)and T1-weighted imaging(T1WI)were also useful for visualization of the area around the flexor retinaculum. The appropriate slice thickness was determined to be 1.5 mm, based on the resolution and photographic time. The flip angle, necessary for tissue resolution, was set at 15° because it provided the clearest image and highest contrast between different tissues. The total photographic time was within 14 minutes, and it is acceptable for routine MRI studies of TTS. In the two cases of TTS included in this study, the tarsal tunnel was clearly visible. For diagnosis of TTS using MRI, axial images obtained by fat-suppression 3D-T2^*WI, 2-dimensional(2D)-T2WI, and 2D-T1WI are recommended. A coronal image obtained by reconstruction of fat-suppression 3D-T2^*WI might be useful for anatomical understanding. In future studies, we plan to evaluate patients with TTS using the above protocol.

Tarsal Tunnel Syndrome Due To Varicose Vascular Structures: A Case Report

Objective: We report a case of a tarsal tunnel syndrome caused by a varicose vascular structures identified by foot MRI. Case report: An eighty-year old male came to our attention for a chronic intermittent bilateral plantar numbness. Symptoms were evident especially in the left foot when taking a bath or after a long distance walk. Feet were bilaterally flat. Ankles range of motion was bilaterally complete and pain free. Resisted range of motion testing including resisted ankle dorsiflexion, plantar flexion, inversion, and eversion was found to be pain free and of equal strength bilater - ally. Neurological testing of the lower extremities was found to be positive for the Tinel sign at level of medial malleolus. Left ankle MRI showed evidence of several varicose vascular structures. One of the varicose vascular structures was suddenly narrow at level of tarsal tun- nel. Posterior tibial vein at the tarsal tunnel level was dilated and appeared to continue in the varicose vascular structure on contrast study. Diagnosis of tarsal tunnel syndrome was made both by symptoms and imaging, considering the dilatation of the posterior tibial vein and the compression of the varicose structures around the tarsal tunnel. Treatment: Resection surgery of the retinaculum was performed in order to decrease the pres- sure on the tarsal tunnel. The patient's symptom reduced after the surgery. However, a few months later he referred recurrence of plantar numbness. Conclusion: Patients who suffer from tarsal tunnel syndrome caused by a varicose vascular structures can show different symptoms if compared with those present in the same syndrome caused by other diseases. If varicose veins are detected in the tarsal tunnel and symptoms of compression are present, along with a concomitant foot deformity that predisposes to disease, diagnosis of tarsal tunnel syndrome should be considered. In order to achieve good results, the treatment of the varicose vascular structures and the correction of foot deformities are recom- mended together with a tarsal tunnel decompression.

Anatomical characteristics of the flexor digitorum accessorius longus muscle and their relevance to tarsal tunnel syndrome a systematic review.

Clinical and cadaver studies have reported that supernumerary muscles could be the etiology of a variety of pathologic disorders, such as posterior impingement syndrome, tarsal tunnel syndrome (TTS), and flexor hallucis longus tenosynovitis. We describe a unique variant of the flexor digitorum accessorius longus (FDAL) muscle as an apparent cause of TTS, functioning as an independent flexor of the second toe, which has not been described in the literature. In addition to this case report, a systematic review was performed of TTS caused by the FDAL muscle. A targeted search of PubMed, the Cochrane Library, the Cumulative Index to Nursing and Allied Health Literature, and Web of Science identified full-text papers that fulfilled the inclusion and exclusion criteria. Twenty-nine papers were identified for inclusion in the systematic review: 12 clinical papers of TTS caused by the FDAL muscle and 17 cadaver-based papers. Clinicians often do not include the FDAL muscle in the differential diagnosis of TTS. This literature review suggests that the FDAL is an important muscle in terms of its functional and clinical significance. Knowledge of this muscle, its anatomical location and variations, and its magnetic resonance imaging characteristics may help clinicians make an accurate differential diagnosis.

Tarsal Tunnel Syndrome in Hemodialysis Patients

The purpose of our study was to investigate tarsal tunnel syndrome (TTS) arising in patients who have undergone maintenance dialysis at our facility and to evaluate the frequency, pathological characteristics, and diagnosis of TTS. We evaluated 1011 patients (mean age 65.1 years) undergoing maintenance dialysis from 2000 to 2006 at our hospital. In patients diagnosed with TTS, we examined clinical symptoms and imaging findings. In addition, we evaluated intraoperative findings in patients who had undergone surgery. A follow-up study was conducted for at least 1 year. Five patients (7 ankles) (mean age 57.8 years) were diagnosed as have TTS, with a mean dialysis duration of 23.4 years (range, 7-30 years). With conservative treatment consisting of rest and a steroid injection, 4 ankles showed improvement. Surgery was performed on 3 ankles. Amyloidoma, nodular tumor fragile deposits in the soft tissue or thecal surface, proliferation of the synovial tendon sheath, and thickened joint capsule were recognized in 3 ankles, and a concomitant ganglion was recognized in 1 ankle. Histologically, the deposition of hyaline material was recognized in all tissues, including the walls of the ganglion or joint capsule, by staining to a pale red color using Congo red stain. An immunohistochemical study indicated positive staining by β-2 microglobulin staining. The flexor retinaculum was thin in all cases, with retinaculum-like thickness not found in carpal tunnel syndrome. We believe that the occurrence of TTS in dialysis patients was 0.5%, with a tendency to be more prevalent among patients undergoing maintenance dialysis for 5 or more years. The pathological process of TTS may be different from that of carpal tunnel syndrome. Level IV, retrospective case series.

The triple compression stress test for diagnosis of tarsal tunnel syndrome

The diagnosis of tarsal tunnel syndrome (TTS) lacks objectivity and consistency. A new test was designed, called triple compression stress test (TCST), to elicit stress on posterior tibial nerve and its branches, in an attempt to provoke signs of its entrapment. In this test, the ankle is placed in full planter flexion and the foot in inversion, with even, constant digital pressure applied over the posterior tibial nerve. Basic clinical examination to fifty patients with symptoms suggestive of TTS in one or both feet was done. Forty healthy volunteers (80 feet) were enrolled as a control group in the study. We then performed our designed clinical TCST, as well as, basic conventional electrodiagnostic studies bilaterally on all patients and controls. Consecutively, electrodiagnostic TCST was done for patients with negative basic nerve conduction results. The clinical TCST was positive in 61 out of 65 (93.8%) symptomatic feet. It provoked symptoms in 6 new asymptomatic feet. The electrodiagnostic TCST was positive in 78 feet, of which 67 had a positive clinical test and 11 had false negative clinical test. Both tests were negative in all the control feet. Clinical TCST sensitivity was 85.9% while specificity was 100%. TCST achieved a simple, fast and very reliable provocative maneuver to increase the sensitivity of TTS diagnosis both clinically and electrophysiologically.

Combination of ultrasound and nerve conduction studies in the diagnosis of tarsal tunnel syndrome

Combination of ultrasound and nerve conduction studies in the diagnosis of tarsal tunnel syndrome

Tarsal tunnel syndrome associated with an accessory muscle.

Between 1986 and 1999, we surgically treated 41 patients (49 feet) with Tarsal Tunnel Syndrome (TTS) in whom seven (eight feet) were associated with an accessory muscle. An accessory flexor digitorum longus muscle was present in six patients, and an accessory soleus muscle was in one patient (both feet). Three of them were males and four females, with the mean age of 33.1 years (12 to 59 years). The mean interval from the onset of symptoms to operation was 7.5 months (range, six to nine months). All patients with an accessory muscle had a history of trauma or strenuous sporting activity. The diagnosis of TTS was made based on physical findings in all the patients (eight feet) and confirmed in five patients (six feet) by electrophysiological examination. Imaging examinations (radiography, ultrasonography, MRI) revealed abnormal bone and soft tissue lesions in and around the tarsal tunnel. Preoperative signs and symptoms disappeared average 4.1 months after decompression of the tibial nerve in addition to excision of the muscle. No functional deficit was observed at final follow-up (24 to 88 months).

The dorsiflexion-eversion test for diagnosis of tarsal tunnel syndrome.

The clinical diagnosis of tarsal tunnel syndrome lacks objectivity and consistency. We have devised a new diagnostic physical examination test in which the tibial nerve is compressed as it runs beneath the flexor retinaculum behind the medial malleolus. In this test, the ankle is passively maximally everted and dorsiflexed while all of the metatarsophalangeal joints are maximally dorsiflexed and held in this position for five to ten seconds. We performed this test on fifty normal volunteers (100 feet) and on thirty-seven patients (forty-four feet) treated operatively for tarsal tunnel syndrome between 1987 and 1997. We performed the maneuver both preoperatively and postoperatively and recorded any consequent changes in the signs and symptoms; during the operation we observed the altered anatomical relationships in the tarsal tunnel that were produced by the maneuver. The average duration of follow-up was three years and eleven months. Before the operation, the signs and symptoms of tarsal tunnel syndrome were intensified or induced by the maneuver in fifteen of the twenty feet of the patients who reported numbness, in fifteen of the seventeen feet of those who reported pain alone, and in six of the seven feet of those who had combined numbness and pain. Local tenderness was intensified in forty-two of forty-three feet, and it was induced in one foot in which it had been previously absent. A Tinel sign became more pronounced in forty-one feet, and the sign was induced in three feet in which it had been absent previously. During the operation, the tibial nerve was stretched and compressed beneath the laciniate ligament when the ankle was dorsiflexed, the heel was everted, and the toes were dorsiflexed. Preoperative signs and symptoms disappeared on an average of 2.9 months after the operation, and they could not be induced by repeating the test except in three patients, all of whom had tarsal tunnel syndrome subsequent to a fracture of the calcaneus. In the normal volunteers, no symptoms or signs could be induced by the test. This new physical examination test is effective in facilitating the diagnosis of tarsal tunnel syndrome.