RELIABILITY OF THE PERONEUS LONGUS, TIBIALIS ANTERIOR AND SOLEUS HOFFMANN REFLEX IN MAN

Abstract

The reliability of the Hoffmann reflex has been well established in the soleus (Sol) by stimulating posterior tibial nerve in the inferior aspect of the popliteal fossa. Reliability of the peroneus longus (PL), tibialis anterior (TA), and Sol H-reflexes by stimulating both the tibial and common peroneal nerves in the superior angle of the popliteal fossa has not been reported. Therefore, the purpose of this work was to investigate H-reflex intrasession reliability in the PL, TA, and Sol. Twelve young, healthy males and females (age: 22.9 ± 4.9 yrs, height: 172.2 ± 7.9 cm, mass: 75.1 ± 12.1 kg) with no history of lower extremity neurological or orthopedic pathologies within the past year volunteered. A within subjects repeated measures design was used. Measurements were recorded at 0 min (baseline), 5 min, 10 min, 15 min, 20 min, 25 min, 30 min, 35 min, and 40 min. H-reflex data were collected from these muscles via percutaneous stimulation of the tibial and common peroneal nerves in the superior aspect of the popliteal fossa. A high voltage (120–200 V), short duration (1.0 msec) stimulus was delivered, eliciting the H-reflex detected via surface EMG. Five to 12 measurements were taken at 20 sec intervals in order to map the maximum PL, TA, and Sol H-reflexes. All subjects received each trial (PL, TA, Sol) in an order predetermined by a balanced Latin Square. The lowest stimulus intensity necessary to elicit the H-reflex for one of the three muscles was used as the testing stimulus intensity for the course of the study. H-reflex means (five trials) were recorded for the PL, TA, and Sol every five min for 40 min. Intrasession reliability was computed using the two-way random effect model. Interclass Correlation Coefficients were estimated for PL [ICC (2,1) = 0.971], TA [ICC (2,1) = 0.944], and Sol [ICC (2,1) = 0.920] H-reflexes. These data indicated that PL and TA H-reflexes are as reliable as previously reported Sol H-reflexes. Furthermore, the PL, TA, and Sol H-reflexes demonstrate high intrasession reliability when stimulating the tibial and common peroneal nerves in the superior popliteal fossa. Thus, the H-reflex can be used to assess motoneuron pool recruitment following joint injury.