Spring ligament injuries: symptoms, causes, and treatments
Lesions of the spring ligament, also called the calcaneonavicular ligament, affect the mobility and instability of the ankle and foot. These lesions can be traumatic or degenerative, they are underdiagnosed, and can lead to various and disabling symptoms.
What is the Spring Ligament and what is its role?
The spring ligament, or plantar calcaneonavicular ligament, connects the calcaneus to the navicular bone and forms the base of the ligamentous complex supporting the head of the talus. It fulfills three essential functions: absorbing compressive forces during walking, ensuring medial stability of the foot, and working in synergy with the posterior tibial tendon to preserve the architecture of the foot.
When this ligament is deficient, it causes overloading of the posterior tibial tendon, creating a vicious cycle of pain and instability. The head of the talus gradually loses its support, leading to a collapse of the foot inward that is characteristic of adult acquired flatfoot deformity, a deformity that worsens if not addressed.
Symptoms of spring ligament injuries
The spring ligament (plantar calcaneonavicular ligament) is a key stabilizer of the medial longitudinal arch of the foot. In case of injury, the typical symptoms are:
- Medial and plantar foot pain, located below and in front of the medial malleolus
- Tenderness to direct palpation of the ligament (between the calcaneus and navicular bone)
- Progressive collapse of the medial longitudinal arch (adult acquired flatfoot)
- Hindfoot valgus (heel tilting outward)
- Forefoot abduction ("too many toes sign": too many toes visible from behind)
- Weakness and rapid fatigue when walking or exercising
- Difficulty or inability to perform a single heel rise (single heel rise test)
- Instability felt in the midfoot
Spring ligament injury is very often associated with posterior tibial tendon insufficiency or rupture (PTTD), as these two structures work together in synergy. Both should therefore be systematically evaluated.
Causes of spring ligament injuries
Injuries to the spring ligament, or calcaneonavicular ligament, can be attributed to several factors, each affecting the structure and function of this essential component of the plantar arch differently.
Spring ligament injuries are often observed in athletes or physically active individuals. These injuries can occur during sudden movements, jumps, or poorly executed landings that put excessive pressure on the spring ligament. High-risk sports include in particular:
- Running, especially on uneven terrain.
- Basketball, where frequent jumps can strain this ligament.
- Football and rugby, involving quick changes of direction.
These activities can cause stretching, tears, or avulsions of the ligament, leading to medial instability of the ankle and foot.
With aging or in the case of a valgus flat foot, this ligament loses its elasticity and strength. Wear of the spring ligament is a natural phenomenon that can significantly weaken the ligament, thus reducing its ability to maintain the plantar arch. These are so-called degenerative lesions, which have a low potential for healing even with surgical repair. This degeneration can be exacerbated by factors such as:
- Obesity, increasing the load supported by the ligament.
- Insufficient physical activity, contributing to decreased muscle strength supporting the ligament.
- Degenerative diseases or chronic inflammatory diseases, which weaken collagen structures.
Some patients are born with anatomical variations that predispose them to spring ligament injuries. Among these factors are:
- Valgus flat foot, which increases the strain on this ligament.
- Genetic anomalies affecting collagen, such as in Ehlers-Danlos syndrome.
- Constitutional ligamentous hyperlaxity which can make ligaments less effective at stabilizing joints.
These conditions can not only predispose to initial instability but also complicate healing after an injury.
Diagnosis of Spring Ligament Lesions: Examinations and Assessments
At La Clinique du Pied, our diagnostic approach combines clinical expertise and targeted complementary examinations to accurately identify spring ligament injuries.
- Clinical examination: palpation of the inner side of the ankle, tests of ligament stability, analysis of the podoscopic footprint, and measurement of the hindfoot alignment (a calcaneal valgus greater than 10° suggests failure of the medial complex).
- Standard X-rays: front, side, and Méary view to rule out associated fractures and measure characteristic angles of flatfoot.
- High-resolution ultrasound: performed 7 to 10 days after trauma, it directly visualizes the spring ligament, measures its thickness (normal between 3.5 and 4.5 mm), and detects pathological areas using color Doppler mode.
- Ankle MRI: prescribed from 20 days post-trauma, with fat-saturated T2 sequences to identify partial or complete tears and associated cartilage lesions.
The combination of early ultrasound and delayed MRI enables a definite diagnosis in 95% of cases.
When is surgery necessary for the Spring Ligament?
Surgical indication is based on the failure of well-conducted conservative treatment over 6 months, a complete rupture of the spring ligament, or measurable progressive deformity (calcaneal valgus greater than 5 degrees, arch collapse greater than 8 mm).
Functional criteria supplement this decision: walking range less than 500 meters, professional incapacity in standing position, or a young athletic profile for whom the period is reduced to 3 months in order to avoid secondary damage.
Available treatments for spring ligament injuries
For the spring ligament injuries that are best tolerated, several non-surgical treatment options can be considered. These methods mainly aim to reduce pain, limit inflammation, and improve the function of the ankle and foot. Among them, you will find:
- Foot orthotics: These custom devices are designed to support the arch of the foot and reduce tension on the ligament and the posterior tibial tendon.
- Physical therapy: Specific exercises can help strengthen the muscles of the ankle and foot, including both the intrinsic and extrinsic muscles of the foot as well as the posterior tibial muscle.
- Anti-inflammatory medications: These are often prescribed to reduce inflammation and relieve pain.
Surgical procedures
In cases where non-surgical treatments do not adequately relieve pain, surgery may be necessary. Isolated repair of the spring ligament carries a high risk of lesion recurrence. It is generally necessary to combine other surgical procedures with the repair to promote healing of the spring ligament. We regularly combine calcaneal osteotomies with medialization of the calcaneal tuberosity to relieve tension on the spring ligament and promote its healing. In case of a highly degenerative spring ligament, reinforcement with surgical strips can also be added.
FAQ: Spring Ligament injuries
The immobilization period ranges from 3 to 6 weeks depending on the technique used and any associated procedures. Normal walking usually resumes between 2 and 3 months postoperatively. A full return to impact sports takes between 4 and 6 months, sometimes longer for intensive sports that involve quick changes of direction.
No, provided that early and appropriate treatment is instituted. The risk of deformity increases significantly if the injury remains untreated for more than 12 months. Foot orthotics with medial arch support prevent collapse in most cases when worn consistently from the time of diagnosis.
A traumatic injury occurs suddenly following an accident or an eversion sprain, causing a partial or complete ligament tear. Degenerative injuries result from gradual wear linked to flatfoot or aging. Prognosis and treatment strategies differ depending on the type, with recent traumatic injuries generally having a better healing potential.
Foot orthotics are the first-line treatment for moderate injuries. Their effectiveness depends on three factors: custom fabrication by an experienced podiatrist, rigorous daily wear in all shoes, and association with a muscle strengthening program. In severe or acute traumatic cases, they are an essential but insufficient complement without other therapeutic intervention.
Three situations require prompt consultation: violent trauma with total inability to walk, massive swelling and extensive bruising appearing within less than 6 hours, or immediate visible foot deformity with collapse of the arch. In these cases, visit the emergency room within 24 hours to rule out a complete rupture or associated bone injuries.
Complete ruptures occur during high-energy trauma, such as road accidents or falls from height. These injuries generally require rapid surgical repair to avoid irreversible deformity. A definitive diagnosis is based on MRI performed at least 20 days afterwards, showing a complete discontinuity of the ligament fibers.
The risk of recurrence remains moderate (15 to 20%) if proprioceptive rehabilitation is thoroughly carried out and support orthotics are worn long-term. We systematically recommend correcting predisposing anatomical factors (excessive calcaneal valgus, hyperlaxity) during surgery to minimize this risk. Regular follow-up for 2 years allows early detection of any new ligament problems.
Conclusion
Lesions of the Spring ligament can be traumatic in high-energy accidents, or degenerative as part of the development towards decompensation of a flat foot, for example. The Spring ligament acts as a true ligamentous lock, helping to stabilize the foot and ankle. Its incompetence generally leads to very disabling inflammatory lesions of the posterior tibial tendon. Depending on clinical tolerance, medical treatment can be considered, notably the use of orthopedic insoles with support for the medial plantar arch. For the most disabling lesions, surgical treatment may be proposed; repairing the Spring ligament is often combined with reinforcement or even a calcaneal osteotomy to protect the repair.