I. Hallux Valgus
A. Epidemiology/overview
1. Hallux valgus is defined as lateral deviation of the proximal phalanx on the first metatarsal head.
2. It is frequently associated with medial deviation of the first metatarsal.
3. Hallux valgus is more common in women than in men.
B. Etiology
1. Hallux valgus is most commonly related to wearing high-heeled shoes that have a narrow toe box.
2. Metatarsus primus varus and pes planus have been implicated.
3. Seventy percent (70%) of patients with hallux valgus have a family history of the condition, which suggests there is a hereditary component.
4. Other causes include rheumatoid arthritis, connective tissue disorders, and cerebral palsy.
5. The metatarsal articular surface may have a valgus (lateral) orientation (as measured by the distal metatarsal articular angle [DMAA]), which can contribute to development of a hallux valgus deformity.
C. Pathoanatomy
1. With valgus deviation of the great toe, the metatarsal assumes a varus position.
2. The sesamoid complex assumes a lateral position relative to the first metatarsal head, which is moved medially.
3. The medial capsule of the hallux metatarsophalangeal (MTP) joint becomes attenuated and the lateral capsule contracts.
4. The adductor tendon, through its insertion on the proximal phalanx and on the fibular sesamoid, becomes a deforming force.
5. With progression, the windlass mechanism is lost, leading to loss of weight bearing under the first metatarsal and transfer to the lesser metatarsals (transfer metatarsalgia).
D. Evaluation
1. History and physical examination
a. A bony prominence may be noted along the medial aspect of the first MTP joint.
b. The patient may report pain along the prominence with shoe wear.
c. Swelling and redness can occur as a result of bursal inflammation.
d. Nerve symptoms may be present with compression of the digital nerve.
e. It is important to consider the patient's activity level and expectations.
f. Hallux valgus is frequently associated with other deformities, such as hammer toes and calluses, from stress transfer laterally.
2. Imaging—Radiographs
a. Weight-bearing AP and lateral views are the most commonly obtained radiographs. A sesamoid view may also be helpful.
b. The angular measurements that are used in the evaluation of hallux valgus are shown in
Table 1 and
Figure 1. These measurements are made on the AP radiographic view.
c. Joint congruency and any significant degenerative changes must be noted.
d. These radiologic parameters guide surgical treatment options.
E. Treatment
1. Nonsurgical
a. Nonsurgical treatment includes shoe-wear modifications, including changing to low-heeled shoes with a wide toe box and soft leather uppers.
b. Occasionally, pads or cushions over the prominence can relieve hallux valgus-related pain.
c. Orthoses may be helpful in patients with pes planus or symptoms of metatarsalgia.
[Table 1. Important Radiographic Angles in the Evaluation of Hallux Valgus]
[Figure 1. Angular measurements of hallux valgus deformity. A, Hallux valgus angle (HVA). B, First-second intermetatarsal angle (IMA). C, Distal metatarsal articular angle (DMMA). D, proximal phalangeal articular angle (PPAA).]
2. Surgical
a. Surgical indications, procedures, and pearls/pitfalls are shown in
Table 2.
b. All components of the deformity must be addressed when choosing a procedure.
II. Juvenile Hallux Valgus
A. Epidemiology/overview—Juvenile hallux valgus occurs more commonly in girls than in boys.
B. Pathoanatomy
1. Typically, the angular deformity associated with hallux valgus is less severe in children than it is in adults.
2. Large medial prominences are rare.
3. A congruent joint with an elevated DMAA is more common in juvenile hallux valgus than in the adult condition.
4. Juvenile hallux valgus can be associated with other deformities such as metatarsus adductus.
5. Generalized ligamentous laxity may be more common in children with hallux valgus than in the general population.
C. Treatment
1. Nonsurgical treatment includes shoe-wear modification and education.
2. Surgical
a. Indications for surgery are shown in Table 2.
b. Open physes at the base of the proximal phalanx or first metatarsal may preclude the use of osteotomies or fusion in those areas to avoid growth arrest.
c. Surgical procedures—Surgical options are similar to those for adults except that, in the presence of open physes, an increased intermetatarsal angle (IMA) is corrected with a medial opening wedge cuneiform osteotomy rather than a proximal metatarsal osteotomy or fusion.
3. Recurrence rates of up to 50% have been noted with surgical treatment.
[Table 2. Surgical Treatment of Hallux Valgus]
III. Hallux Varus
A. Epidemiology/overview
1. Hallux varus is defined as a hallux valgus angle (HVA) measuring ≤0°.
2. The condition can be associated with an extension deformity of the MTP joint and flexion of the interphalangeal (IP) joint. Supination of the hallux may be seen as well.
B. Etiology
1. The most common cause of hallux varus is iatrogenic deformity resulting from hallux valgus repair (2% to 10% incidence), which can be due to excessive tightening of the medial joint capsule, excessive resection of the medial eminence, overcorrection of the IMA, excision of the fibular sesamoid, or excessive lateral capsular release.
2. Hallux varus may be associated with inflammatory conditions, such as rheumatoid arthritis, or neurologic conditions, such as Charcot-Marie-Tooth disease.
C. Evaluation
1. History and physical examination
a. Hallux varus is principally asymptomatic.
b. The most commonly reported symptom is difficulty with shoe wear due to a prominent IP joint.
c. Transfer lesions may develop along the lesser metatarsals.
d. Determination must be made regarding the fixed or passively correctable nature of the MTP and IP joint deformities.
2. Imaging—Weight-bearing radiographs can help determine the degree of arthrosis.
D. Treatment
1. Nonsurgical—Taping of the toe, placing pads over prominent areas, and wearing shoes that have extra depth and a wide and flexible toe box can be helpful.
2. Surgical
a. Procedures
i. Flexible deformities can be treated with medial capsular release/lengthening and a tendon transfer.
ii. Initially, the entire extensor hallucis longus tendon was rerouted under the intermetatarsal ligament to the base of the proximal phalanx; this required fusion of the IP joint.
iii. Methods for maintaining IP joint motion include a split transfer of the extensor hallucis longus tendon or rerouting of the extensor hallucis brevis tendon.
b. Fixed deformities or those with significant arthrosis require fusion of the MTP joint for correction.
IV. Hallux Rigidus
A. Overview/epidemiology
1. Hallux rigidus describes a degenerative arthritic process that leads to functional limitation of motion in the first MTP joint.
2. Periarticular osteophytes can create a mechanical block to dorsiflexion.
B. Etiology
1. The primary etiology has not been determined.
2. An acute traumatic event to the MTP joint can lead to joint degeneration.
3. Repetitive microtrauma has also been implicated.
4. Anatomic variations in the first metatarsal have been suggested but remain unproven with regard to their causative role.
C. Evaluation
1. History and physical examination
a. Patients report joint pain and swelling with limited dorsiflexion of the MTP joint.
b. Dorsal osteophytes can lead to shoe-wear irritation.
c. Compression of the dorsal cutaneous nerve between the osteophyte and the shoe can lead to paresthesias.
d. Imaging—Radiographic evaluation with AP, lateral, and oblique views may reveal the presence of osteophytes around the joint, joint-space narrowing, subchondral sclerosis, and cysts.
D. Treatment
1. Nonsurgical
a. Mild synovitis can be treated with activity modification and nonsteroidal anti-inflammatory medication.
b. Orthotic devices that increase the rigidity of the forefoot portion of the shoe can limit MTP dorsiflexion and help relieve symptoms.
c. An extra-depth shoe can accommodate large dorsal osteophytes, and the use of a stiff-soled rocker bottom or metatarsal bar can be helpful.
2. Surgical
a. Indications—Surgical treatment is indicated when nonsurgical treatment fails.
b. The symptoms and degree of arthrosis help determine the best surgical options.
c. Procedures
i. Joint debridement and synovectomy may be indicated for patients with an acute chondral or osteochondral injuries.
ii. Cheilectomy involves resection of the dorsal osteophyte along with removal of 25% to 30% of the dorsal aspect of the metatarsal head (
Figure 2). The goal is to obtain 70° to 90° of dorsiflexion intraoperatively. The degree of joint arthrosis that precludes success is controversial. Pain within the midrange of passive motion may be an indicator of poor prognosis with cheilectomy. A patient whose main complaint is shoe wear irritation from the prominence or pain with dorsiflexion is the best candidate for cheilectomy.
iii. Dorsal closing wedge (Moberg) osteotomy of the proximal phalanx is used to increase dorsiflexion of the MTP joint by decreasing the plantar flexion arc (
Figure 3). It is usually combined with a cheilectomy and is indicated if cheilectomy does not provide at least 30° to 40° of dorsiflexion.
[Figure 2. Metatarsal dorsal cheilectomy. A, Lateral view of the first metatarsal with suggested resection of both the dorsal osteophyte and a portion of the metatarsal head (gray shaded area). Bone removal is indicated by the black arrow. B, Lateral view of the first metatarsal after resection.]
[Figure 3. A, Lateral view of the proximal phalanx showing the location of a dorsal closing wedge proximal phalangeal osteotomy (gray shaded area). Bone removal is indicated by the black arrow. A cheilectomy was also performed. B, Dorsiflexion increase as a result of dorsal closing wedge osteotomy.]
iv. Resection arthroplasty (Keller procedure) involves removal of the base of the proximal phalanx; it is intended to decompress and improve motion in an arthritic joint. However, it can destabilize the joint, leading to a cock-up deformity, weakness during push off, and transfer metatarsalgia. These complications limit its utility in elderly or more sedentary patients. A modification of the procedure involving capsular interposition has been reported to reduce these complications.
v. Arthrodesis of the MTP joint is the most commonly used procedure for severe hallux rigidus. Fusion rates have ranged from 70% to 100%. Degeneration of the IP joint is seen in 15% of patients after surgery; however, most patients are asymptomatic. Excessive dorsiflexion can lead to pain at the tip of the toe, over the IP joint, and beneath the first metatarsal head. Excessive plantar flexion can cause increased pressure at the tip of the toe. The preferred alignment is 10° to 15° of valgus and 15° of dorsiflexion relative to the metatarsal shaft. Excessive valgus may increase the risk of hallux IP joint degeneration.
vi. The use of implants in the MTP joint has a high failure rate and is rarely indicated.
V. Turf Toe Injuries
A. Epidemiology/overview
1. Turf toe injury is defined as an injury of varying severity to the periarticular structures surrounding the hallux MTP joint.
2. The flexibility of shoes used on artificial turf and the shoe-surface interface have been suggested as causative factors.
3. The most common mechanism of turf toe injury is hyperextension of the MTP with an axial load applied to a plantar flexed foot.
4. Unlike turf toe injuries, hyperflexion injuries are frequently seen in beach volleyball players; hence, they are termed "sand toe" injuries.
B. Evaluation
1. History and physical examination
a. Determining the location of tenderness can help identify injured structures.
b. An intrinsic minus position of the hallux, with the MTP joint extended and the IP joint flexed, indicates a severe injury.
2. Imaging—Radiographic evaluation with weight-bearing AP, lateral, oblique, and sesamoid views is indicated. Proximal migration of the sesamoids on an AP radiograph indicates a complete rupture of the plantar plate.
C. Treatment
1. Nonsurgical
a. Most injuries can be treated with rest and analgesics.
b. More severe injuries may require use of a walker boot or short leg cast until the joint is stable.
c. Joint mobilization is begun once the injury is stable.
d. Severe injuries may require up to 12 weeks to heal before the patient can return to activity.
2. Surgical
a. Surgical treatment is rarely needed.
b. Surgery is indicated when there is retraction of the sesamoids, sesamoid fracture with diastasis, traumatic bunions, or loose fragments in the joint.
c. If plantar plate or flexor tendons cannot be restored, an abductor hallucis tendon transfer may be needed.
VI. Sesamoid Disorders
A. Epidemiology/overview
1. The sesamoids function to absorb and transmit weight-bearing pressure, reduce friction, protect the flexor hallucis longus tendon, and help increase the mechanical force of the flexor hallucis brevis tendon. The flexor hallucis longus tendon glides between the two sesamoids.
2. The tibial sesamoid is bipartite in approximately 10% of the population; in 25% of those people, the condition is bilateral. The medial (tibial) sesamoid is larger and more affected by weight bearing; thus, it is more commonly injured.
B. Evaluation
1. History—Patients will present with pain along the plantar aspect of the metatarsal head.
2. Physical examination—A plantar-flexed first ray with a cavus deformity may be noted on examination.
3. Imaging
a. AP and lateral radiographs may reveal the presence of fractures or degenerative changes.
b. Individual oblique views can help isolate the sesamoids, and an axial view can help evaluate the articulation with the metatarsal head.
4. A bone scan may be helpful but should be interpreted with caution because 25% to 30% of asymptomatic patients may show increased up-take. A significant difference in uptake between the injured and uninjured sides is helpful in confirming injury.
C. Treatment
1. Nonsurgical
a. Reducing weight bearing under the first metatarsal and limitation of activities are the mainstays of nonsurgical treatment.
b. The use of pads, rocker soles, and metatarsal bars also may be effective.
c. Shaving of keratotic lesions can reduce symptoms.
d. Controversy exists in the treatment of acute fractures. Some authors recommend the use of a short leg cast with a toe extension, others use a stiff-soled shoe or boot with a pad around the sesamoid.
2. Surgical
a. Indications—Surgery is indicated after 3 to 12 months of failed nonsurgical treatment.
b. Procedures
i. Bone grafting of sesamoid nonunions has been reported to have good results in a study with a small group of patients.
ii. Dorsiflexion osteotomy should be considered for the patient with a plantar flexed first ray.
iii. Excision of the sesamoid may be required after failure of nonsurgical treatment efforts.
c. Complications
i. Tibial sesamoid excision may lead to hallux valgus.
ii. Fibular sesamoid excision may lead to hallux varus.
iii. Excision of both sesamoids should be avoided, as a cock-up deformity of the toe may occur.
Top Testing Facts
Hallux Valgus
1. Congruency of the joint and degree of articular degeneration are important parameters to consider for treatment. Soft-tissue release should not be performed on a congruent joint.
2. To decrease the risk of hallux varus, avoid fibular sesamoid excision during distal soft-tissue release.
3. To minimize the risk of osteonecrosis, avoid an extensive lateral capsular release during (chevron) distal metatarsal osteotomy.
4. Patients with an IMA >13° need proximal metatarsal osteotomy combined with distal soft-tissue release to correct the deformity.
5. A DMAA >15° can be corrected with biplanar (closing wedge) distal metatarsal osteotomy (chevron).
6. MTP fusion is recommended for patients with inflammatory conditions, such as rheumatoid arthritis, or neurologic disorders, such as cerebral palsy.
Juvenile Hallux Valgus
1. A congruent joint with an elevated DMAA is more common in juvenile hallux valgus than in the adult condition.
2. Recurrence rates of up to 50% have been noted with surgical treatment of hallux valgus in juveniles.
Hallux Varus
1. The most common cause of hallux varus is iatrogenic deformity resulting from hallux valgus repair (2% to 10% incidence), which can be due to excessive tightening of the medial joint capsule, excessive resection of the medial eminence, overcorrection of the IM angle, excision of the fibular sesamoid, or excessive lateral capsular release.
2. Hallux varus is principally asymptomatic and most patients can be treated nonsurgically.
3. If the painful deformity is passively correctable, a soft-tissue procedure with tendon transfer can be performed.
4. If the painful deformity is fixed or significant arthrosis is present, then fusion of the MTP joint is recommended.
Hallux Rigidus
1. Hallux rigidus describes a degenerative arthritic process that leads to functional limitation of motion in the first MTP joint.
2. Periarticular osteophytes can create a mechanical block to dorsiflexion.
3. Cheilectomy involves resection of the dorsal osteophyte along with removal of 25% to 30% of the dorsal aspect of the metatarsal head.
4. A patient whose main complaint is shoe-wear irritation from the prominence or pain with dorsiflexion is the best candidate for cheilectomy.
5. Dorsal closing wedge (Moberg) osteotomy is usually combined with a cheilectomy and is indicated if cheilectomy does not provide at least 30° to 40° of dorsiflexion.
6. Arthrodesis of the MTP joint is the most commonly used procedure for severe hallux rigidus. The preferred alignment is 10° to 15° of valgus and 15° of dorsiflexion relative to the metatarsal shaft. Excessive valgus may increase risk of hallux IP joint degeneration.
7. The use of implants in the MTP joint has a high failure rate and is rarely indicated.
Turf Toe Injuries
1. The most common mechanism of turf toe injury is hyperextension of the MTP joint with an axial load applied to a plantar flexed foot.
2. Determining the location of tenderness can help identify injured structures. The ability and comfort associated with weight bearing can give an indication of the severity of injury.
3. An intrinsic minus position of the hallux, with the MTP joint extended and IP joint flexed, indicates a severe injury.
4. An AP radiograph of the foot showing proximal migration of the sesamoids indicates a complete rupture of the plantar plate.
5. The severity of the injury varies significantly and determines the time needed for recovery. Severe injuries may require use of a walker boot or short leg cast until the joint is stable.
6. Surgery is indicated when there is retraction of the sesamoids, sesamoid fracture with diastasis, traumatic bunions, or loose fragments in the joint.
Sesamoid Disorders
1. The sesamoids sit within the flexor hallucis brevis tendon and help increase its mechanical force.
2. The flexor hallucis longus tendon glides between the two sesamoids.
3. The tibial sesamoid is bipartite in approximately 10% of the population; in 25% of those people, the condition is bilateral.
4. The medial (tibial) sesamoid is larger and more affected by weight bearing; thus, it is more commonly injured.
5. A plantar-flexed first ray with a cavus deformity may be noted on examination and may need correction with a dorsiflexion osteotomy of the metatarsal.
6. Radiographs may reveal the presence of fracture or degenerative changes of the sesamoids.
7. A bone scan may be helpful but should be interpreted with caution because 25% to 30% of asymptomatic patients may show increased uptake.
8. Tibial sesamoid excision may lead to hallux valgus and fibular sesamoid excision may lead to hallux varus. Excision of both sesamoids should be avoided, as a cock-up deformity of the toe may occur.
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