Purpose: Tarsal tunnel syndrome (TTS) is a painful foot condition. Lumbosacral radiculopathy (LR) may also present with symptoms occurring in TTS. However, no studies have been reported to determine the possible coexistence of these two conditions. The aim of our study was to identify the prevalence of TTS in patients with confirmed LR and to analyze the clinical and electrodiagnostic features of patients with both TTS and LR.
Methods: Medial and lateral plantar nerve mixed studies, peroneal motor studies and deep peroneal sensory studies were performed in 81 normal subjects and 561 patients with LR. The Tinel's test and other provocative tests were performed in the LR patient group, and the clinical symptoms of TTS were also analyzed. The frequency of TTS was investigated in all radiculopathy group patients with different nerve root lesions.
Results: Concomitant TTS was found in 27 (4.8%) patients with LR. Abnormal results of sensory/mixed conduction tests were observed in 25/27 (92.6%) patients, and 11/27 (40.7%) patients had abnormal results of motor conduction tests. Positivity for the Tinel's test and special provocative tests was found in 15/27 (55.6%) and 17/27 (63.0%) patients, respectively. Overall, 9/27 (33.3%) patients had typical symptoms, and suspicious clinical symptoms were found in the other 14/27 (51.9%) patients. The frequency of coexisting TTS was not statistically different among the single-level L4, L5 or S1 radiculopathy, or between the single-level and multi-level radiculopathies (P > 0.05).
Conclusions: The findings suggest that the prevalence of TTS is significant in patients with LR. Thus, more caution should be paid when diagnosing and managing patients with LR due to the possible existence of TTS, as their management strategies are quite different.
Keywords: Double crush syndrome; Lumbosacral radiculopathy; Nerve conduction study; Tarsal tunnel syndrome.