The Silfverskiöld Test Testing for gastrocnemius and soleus tightness
Calf tightness plays a role in many etiologies of the foot, ankle, and knee, influences gait and stride in walking and running, and is seen in many patients with symptomatic foot, ankle, and knee pain. Isolated gastrocnemius tightness can be determined by the Silfverskiöld maneuver or test, whereby the degree of ankle dorsiflexion is compared and measured with the knee flexed and the knee fully extended. This was described passively but can also be checked for active as well as passive motion (controlling for subtalar motion).
Normal ankle dorsiflexion with the knee extended equals > 10°and with flexion of the knee ideally an additional 10°of dorsiflexion is noted. Gait analysis data suggest that the average individual relies maximally on about 10° of ankle dorsiflexion during the late-stance phase of normal walking.
During the transition from foot flat to heel off, the foot normally dorsiflexes as the body moves forward. Gait consequences of decreased ankle dorsiflexion or equinus contracture include adoption of a toe to toe gait pattern or a toe to heel gait pattern leading to premature forefoot loading, reduced propulsion, excessive knee hyperextension, excessive foot pronation (allowing more dorsiflexion to occur through the subtalar joint), reduced stride length of the opposite limb, reduced gait velocity, and possible external rotation of the leg. A patient bearing weight on a contracted plantar flexed ankle is susceptible to a host of secondary conditions, such as plantar fasciitis, flatfoot deformity, hallux valgus, achilles tendonitis, and plantar ulcerations, as well as more proximal chain problems including knee pain. Differential diagnoses of gastrocnemius or achilles tightness should include anterior ankle impingement, leg length discrepancy, cerebral palsy, and hyperpronation of the foot.
The Silfverskiöld test differentiates gastrocnemius tightness from an achilles tendon contracture by evaluating ankle dorsiflexion with the knee extended and then flexed. Increased ankle dorsiflexion with knee flexion indicates gastrocnemius tightness. This occurs because the gastrocnemius relaxes with knee flexion as the muscle spans the knee joint and the soleus does not. If there is no difference in dorsiflexion with flexion of the knee, then an achilles tendon contracture is present (assuming no bony impingement or significant arthritis).
Gastrocnemius and calf tightness causes may include footwear (particularly high-heeled shoes keeping calves in a state of perpetually shortened length), running without an appropriate flexibility and strengthening program, inadequate stretching after exercise, constant walking or standing (causing muscle shortening), genetics, and muscle weakness elsewhere in the leg causing overuse of the calves. There is a synergistic relationship between the hamstrings and calves with associated hamstring and gastrocnemius tightness found in patients with plantar fasciitis and in functional screening of patients and athletes with tight calves/hamstrings.
Passive stretching exercises are encouraged and dorsiflexion exercises should be performed with the knee fully extended and bent to address both gastrocnemius and soleus issues. Associated weak dorsiflexors, peroneal tendons, and posterior tibialis should be addressed as well. Multi-planar stretches and training work the muscles from different angles, possibly recruiting more muscle fibers, and engaging more of the small stabilizing muscles. Nonsurgical measures work for many patients and there are some attached stretching exercises to share with your patients and therapists. An eccentric strengthening program for both the gastrocnemius and soleus is beneficial as well. Patients with fixed deformities should have possible consideration of gastrocnemius release or Achilles tendon lengthening in certain cases.
References:
DiGiovanni CW, Kuo R, Tejwani N, et al: Isolated gastrocnemius tightness. J Bone Joint Surg Am 2002;84(6):962-970. SilfverskiöldN.: Reduction of the uncrossed two-joints muscles of the leg to one-joint muscles in spastic conditions. Acta Chir Scand;1924;56:315-30. Harty J, Soffe K, O’Toole G, Stephens MM: The role of hamstring tightness in plantar fasciitis. Foot Ankle Int. 2005:26(12):1089-92.Below are some stretches that we use for some people with calf and hamstring tightness. For all of these stretches we would like the patient to stretch lightly and to avoid overdoing it.
· For all exercises besides ankle pronation/supination: Hold for 20 seconds and repeat 5 times · For ankle pronation/supination exercise: May repeat up to 5 times daily.
