The great toe consists of several joints, including the first metatarsophalangeal (MTP) joint and the interphalangeal (IP) joint. Most disorders of the great toe affect primarily the first MTP joint. The first MTP joint consists of the articulation between the metatarsal head (J in Figure 1) and the proximal phalanx (O), as well as the articulation between the plantar aspect of the metatarsal head and the sesamoids. A sesamoid bone is a bone that is also part of a tendon. An easy example of such a bone is the kneecap (patella). In the foot there are two sesamoid bones (Figure 2), each of which is located directly underneath the first metatarsal head. These sesamoids are part of the flexor hallucis brevis tendon, and act to increase the force of the tendon on the proximal phalanx. They also act to absorb shock and allow the joint to glide smoothly during motion. The range of motion of the first MTP joint is greatest in the sagittal plane and consists of approximately 15 degrees of plantar flexion to 75 degrees of dorsiflexion from standing position.
Figure 1: Bones of foot
Figure 2a: Sesamoid bones (arrows) at the base of the first MTP joint
Figure 2b: Sesamoid bones embedded in flexor hallucis brevis tendons
. (credit: Wikipedia.org)
The first MTP joint is very important biomechanically to normal foot function because stability of the first MTP joint in turn leads to stability of the medial column of the foot. According to Stokes et al., approximately 40% to 60% of body weight passes through the first MTP joint and great toe during normal gait (PMID:498650). During athletic activities like jogging and running, these forces can approach two to three times body weight.
In hallux rigidus, it is thought that overuse of the joint leads to wear and tear, causing degenerative changes in the joint itself and the soft tissue surrounding the joint. The loss of joint cartilage, which occurs first along the top half (dorsal) of the MTP joint, is believed to result from changes in joint dynamics that lead to in increased pressure across the joint as the toe bends upward. This can take many years to develop, but can become quite symptomatic. In the later stages of this disease process, cartilage covering the remainder of the joint surface also erodes, leading to a progressively worse and more bothersome arthritic joint.
Risk factors for hallux valgus deformity, with varying evidence in the literature , have been reported to include: pes planus (flat foot), 1st ray hypermobility (1st ray consists of the hard and soft tissues of the first metatarsal, the sesamoids, and the phalanges of the great toe) occupation, footwear , occupationconstrictive shower, heredity factors, Achilles contracture, and ligamentous laxity. Although there are many stabilizing structures crossing the MTP joint, there are no tendons to prevent medial deviation of the distal metatarsal . Therefore, normal alignment of the 1st MTP joint is a product of a delicate balance of abducting and adducting forces.
Sesamoiditis is a general term for painful inflammatory symptoms associated with either one or both of the sesamoid bones. The tibial (medial) sesamoid is subject to more force and is naturally more prone to injury. The mechanism of injury is usually associated with repetitive, excessive loading of this area of the foot, but it can also be due to trauma or forced dorsiflexion. Often patients will have a higher arched foot, causing the sesamoids to be subjected to greater force with each step. The resulting pathology may include chronic soft-tissue injury, stress fracture of one of the sesamoids or a sesamoid which never heals (nonunion) after injury, or cartilage damage (arthritis) between the sesamoid and the first metatarsal head.
Patients with hallux valgus will often display pain over the prominent bump on the inside of their forefoot (the medial eminence). However, they may also have pain under the ball of the foot (under the area near the base of the second toe). Symptoms can vary in severity from none at all to severe discomfort aggravated by standing and walking. There is no direct correlation between the size of the bunion and the patient’s symptoms . Some --some patients with severe bunion deformities have minimal symptoms, while patients with mild bunion deformities may have significant symptoms. Symptoms are often exacerbated by restrictive shoe wear, particularly shoes with a narrow toe box or an uncomfortable, stiff, restraining upper.
Physical examination typically reveals a prominence on the inside (medial) aspect of the forefoot (Figure 3). This represents the bony prominence associated with the first MTP joint (the medial aspect of the first metatarsal head). The great toe is deviated laterally and often rotated slightly. This produces first MTP joint subluxation. In mild and moderate bunions, this joint may be repositioned back to a neutral position (reduced) on physical examination. With increased deformity or arthritic changes in the first MTP joint, this joint cannot be fully reduced. Patients may also have a callus at the base of their second toe under their second metatarsal head in the sole of the forefoot. Bunions are often associated with a long second toe.
Figure 3: hallux valgus
Patients with hallux rigidus will typically present with pain, stiffness, and swelling in the first MTP joint (Figure 4). This is aggravated by activities that involve excessive repetitive upward movement of the big toe joint such as sprinting, running, or even prolonged walking. Swelling usually occurs along the top (dorsal) half of the joint, and will frequently be associated with bone spur formation recognized as a “new prominence” by the patient (Figure 5). In the early stages of hallux rigidus, there is pain at terminal range of dorsiflexion and plantarflexion. In the late stages, there is loss of motion, especially dorsiflexion, sometimes with crepitus at mid-arc of motion. Patient may complain of a dorsal prominence from osteophtyes or synovitis. As the condition progresses patients often compensate by putting more weight on the outside of the foot as they walk. This may cause metatarsalgia, or pain in the forefoot, or in rare instances a Jones fracture of the 5th metatarsal base..
Figure 4: hallux rigidus pain location
Figure 5: hallux rigidus osteophyte formation
Physical examination will reveal limited and often painful motion in the big toe joint, particularly when the patient is weight bearing through the forefoot. Prominent osteophytes on the dorsal aspect of the joint are usually visible and palpable. It is very common to see these findings in both feet, although usually one foot is more symptomatic than the other. Tenderness to touch is common dorsal to the swollen MTP joint.
Turf toe injuries result in pain on the plantar surface at the base of the first MTP joint. They usually occur after an acute injury although repetitive forced upward movement of the great toe may also lead to an injury of the capsule stabilizing the great toe joint. Turf toe is commonly seen in contact sports such as football, soccer, and rugby. It can also occur in high impact sports such as gymnastics and dance. Commonly Typically an athlete will be changing direction suddenly on the playing field and the great toe will be forced upwards as the foot rolls over the toe which is planted on the ground. With enough force the capsule or ligamentous tissue on the under surface (plantar aspect) of the great toe will be torn either partially or completely. Moving the great toe upwards will often create pain. Patients will complain of pain in the great toe, noticeable swelling, a limp, and an inability to run on the foot. If the capsule is significantly torn the great toe joint may be noted to be unstable.
Hallux valgus deformity is usually obvious upon physical examination, but it is also easily demonstrated on plain X-ray (Figure 6). A weight-bearing foot series should be obtained to assess forefoot alignment, including the presence of lesser toe deformity, and evaluated for degenerative changes at the IP, MTP, and metatarsal cuneiform (MTC) joints. A weight-bearing anterior-posterior (AP) radiograph assesses hallux valgus angle (HVA), intermetarsal angle (IMA), MTP joint congruency, and sesamoid position.This evaluation allows for classification and preoperative planning. The lateral radiograph should be assessed for plantar gapping at the 1st MTC joint and dorsal translation of the 1st MT relative to the cuneiform which is indicative of instability.
Figure 6: AP X-ray of hallux valgus
The only definitive way to diagnose an acute gouty attack is to aspirate the joint. Patients with gout will demonstrate synovial fluid leukocytosis (predominantly neutrophils) and the presence of negatively birefringent, needle-shaped crystals viewed using a polarizing microscope (Figure 7). Even with these findings, a simultaneous infection is not definitively excluded. Accordingly, synovial fluid aspirated for gout should always be assessed for infection by Gram stain and culture.
Figure 7: negatively birefringent MSU crystals seen in gout under polarizing microscope
X-rays in turf toe injuries are usually negative, as this injury predominately affects the soft -tissue around the MTP joint. However, plain x-rays should be reviewed to rule out other injuries such as sesamoid fractures and other fractures involving the great toe. A stress x-ray or fluoroscopy may demonstrate excessive movement (instability) of the MTP joint when it is stressed. An MRI will reveal evidence of the soft-tissue (capsular) injury.
When sesamoiditis is suspected, plain x-rays of the foot are always indicated to help diagnose this problem as well as rule out other potential problems in this region of the foot. They permit proper assessment of the entire forefoot region, and, in particular, look at allow visualization of the two sesamoids and how they sit anatomically beneath the first MTP joint. Fractures, subluxations, dislocations, osteochondrosis, or avascular necrosis affecting the sesamoid(s) can usually be diagnosed on these plain x-rays. It is common to be born with sesamoids that are naturally in several pieces, called bipartite (two pieces) or multipartite (many pieces) sesamoids. While the normal sesamoid is a singular roundish bone the size of a pea, these types almost look like the bone has been broken. They are simply a normal variant, however, and need to be carefully distinguished from true fractures. Bipartite or multipartite sesamoids may cause pain in certain circumstances, but they are usually asymptomatic. The best way to make this diagnosis is One way to help differentiate a sesamoid fracture from a bipartite sesamoid is to get x-rays of the opposite side, since bipartitie sesamoids are often bilateral whereas a true fracture is usually not.
When hallux rigidus is suspected, weight bearing foot x-rays should be obtained and these will typically identify some loss of first MTP joint cartilage, seen as narrowing of this space on the x-ray – as compared to other similar spaces seen in nearby unaffected joints. There may be squaring of the metatarsal head on the anterior and posterior view. The lateral view will often show a prominent dorsal bone spur (Figure 8).
Figure 8a: AP x-ray, hallux rigidus
Figure 8b: Lateral x-ray, hallux rigidus
The most common disorder of the great toe is hallux valgus. According to a meta-analysis performed by Nix et al. (PMID:20868524), the prevalence of hallux valgus in patients aged 18-65 is 23% , and is increasing to 35% in patients older than 65 years. In addition to the elderly, hallux valgus is more prevalent in females , and it has been hypothesized that this is due in part to the types of shoes commonly worn by women. a hereditary component with most hallux valgus patients having a first degree family member with the condition. Hallux valgus is important because it not only contributes to much of the cost of forefoot surgery, it also causes pain and gait changes that may affect the biomechanics of walking and running.
Gout prevalence has doubled over the past several decades, and gout is now the most common inflammatory arthritis. Factors contributing to this rise include the obesity epidemic and the rising prevalence of metabolic syndrome, the aging of the population, and an increase in chronic kidney disease. Gout results from elevated drum uric acid (sUA). Because sUA in males but not females rises at puberty, gout before older age is almost exclusively a male disease. At menopause, sUA rises in women as well; consequently gout is not uncommon in the older female population. Gout is distinctly rare in children, but may occur when genetic mutations affect urate metabolism. Currently the overall prevalence of gout in the US is 2-4%, but is 10% or greater in older adults.
Differential diagnosis for pain at the first MTP joint includes all of the disorders mentioned previously, as well as infection, stress fracture, tendon disorders, non-neoplastic soft-tissue masses, and rarely neoplastic soft-tissue and bone neoplasms. Imaging, along with A detailed clinical history, good physical examination, and appropriate imaging can be used to differentiate between different disordersthe various disorders of the great toe.
As stated previously, hallux valgus is fairly easy to diagnose on physical exam. However, it is important to note that hallux valgus is not mutually exclusive of any of the other disorders previously mentioned. For example, a patient with hallux valgus may also suffer from hallux rigidus, sesamoiditis, turf toe, or gout. Therefore, it is important to take a detailed clinical history upon patient presentation even if a hallux valgus deformity is obvious. It is important to determine the exact cause of pain, especially if planning a surgical intervention, so that each problem can be addressed intra-operatively. If it is assumed that the cause of pain is hallux valgus without a more detailed clinical history or imaging, it is possible to miss the real cause of pain (ex. metatarsalgia) and perform an operation that does not address the clinical problem.
When an athlete presents with an acute injury of the first MTP joint following forced hyper-extension of the hallux, the diagnosis is almost certainly turf toe. However, turf toe is a broad category that that encompasses different severities of capsular injury, from attenuation of the capsule to a complete tear. Plain x-rays should be reviewed to rule out other injuries such as sesamoid fractures and other fractures involving the great toe.
Imaging studies should be performed in most cases of first MTP joint pain, especially with recalcitrant pain following conservative treatment, in order to make facilitate an accurate diagnosis and plan future treatments accordingly. These studies should also rule out any neoplastic cause of pain.
A single gout attack is extremely painful but usually self-limited. A missed diagnosis at that time will be of little long-term consequence. However, a missed diagnosis of an infected joint can be catastrophic; because gout and infection are often clinically indistinguishable, diagnostic joint aspiration should almost always be performed. On the other hand, chronic gout can be debilitating and accompanied by increased morbidity and mortality. Therefore, the importance of long-term treatment should not be underestimated.
Treatments of hallux valgus, hallux rigidus, disorders of the sesamoid, and turf toe include both conservative and operative options, and which ones are ultimately chosen . The treatment that is indicated will depend on a variety of factors. Conservative treatments are similar for all of these disorders, while the operations performed differ depending on the disorder. Conservative treatments include:
- activity modification,
- modification of shoe wear,
- shoe inserts to reduce stress on the first MTP joint,
- anti-inflammatory medication (NSAIDs),
- steroid injection in recalcitrant cases.
The primary indication for operative intervention should be pain that is not relieved by appropriate non-operative management.
Operative treatment for hallux valgus is not indicated for cosmetic reasons. The prolonged recovery time associated with most bunion operations, combined with the potential for complications means that patients should be extremely cautious of undergoing bunion surgery for purely cosmetic reasons. There are hundreds of different surgical treatments for hallux valgus described in the orthopaedic literature. The type of procedure chosen depends on the severity of hallux valgus, co-morbid conditions, and the preference of the surgeon. Some of the common procedures are:
- removal of the medial eminence,
- distal metatarsal osteotomy (chevron) with great toe soft-tissue tightening (medial capsular tightening and distal soft-tissue repair),
- proximal metatarsal osteotomy (Ludloff, Cresentic, SCARF, medial opening wedge) with with great toe soft-tissue tightening (medial capsular tightening and distal soft-tissue repair),
- lapidus hallux valgus correction (first tarsometatarsal joint fusion) with distal soft tissue procedure,
- great toe fusion (1st MTP joint arthrodesis),
- Akin osteotomy (Realignment bone cut at the base of the big toe),
- removal of the medial eminence with suture stabilization of the first and second metatarsals,
- Keller joint arthroplasty (removal of the proximal aspect of the proximal phalanx).
Each of these are similar in that it is often 9-12 months before maximal recovery is achieved. Patients recovering from these procedures can have persistent swelling for several months due to increased blood flow as part of the healing process. Usual post Post-surgical complications , although rare, include wound are not uncommon and may include: wound healing problems, infection, nonunion, local nerve injury, deep venous thrombosis (DVT), and pulmonary embolism (PE). Additionally, the deformity may recur or a new deformity may form at the osteotomy, requiring an additional surgery. The first MTP joint may also lose some range of motion following a procedure.
Operative treatment for hallux rigidus when non-operative treatments fail include:
- 1st MTP joint dorsal cheilectomy (bone spur removal),
- fusion of the first MTP joint,
- first MTP joint arthroplasty (first MTP joint replacement).
The dorsal cheilectomy procedure is effective only for patients who have arthritis involving just the dorsal aspect of the first MTP joint. It is not indicated in patients with extensive arthritis involving the entire joint (ie, more severe or end/late-stage hallux rigidus). Patients are typically able to rapidly remobilize with weight bearing as tolerated in a stiff-soled shoe as soon as the incision heals after surgery which often takes about 2 weeks. However, residual pain and swelling can be expected to limit some activities for at least a few more months post-operatively. Recurrence of pain is a possible complication of cheilectomy and if this occurs the other two surgical options should be considered. Fusion of the great toe joint is the most common, and most predictable surgical treatment for more severe hallux rigidus.
Recalcitrant sesamoiditis that does not improve with 6 months of conservative treatment can be considered for operative treatment. Various forms of surgery to offload the sesamoid can also be considered in extenuating circumstances, such as with patients who present with anatomical mechanical overload as a result of high arched feet. Surgery too, however, remains a rare requirement to treat the majority of these patients. One such surgical option is to excise the painful sesamoid bone. However, this can lead to hallux varus or valgus, depending on which sesamoid is removed, and destabilization of the joint.
In turf toe injuries where there is complete tearing of the plantar soft-tissues of the great toe surgical repair may be neededis indicated. Additionally, some turf toe injures resulting in partial tearing of the plantar capsule that do not adequately recover with conservative treatment may benefit from turf toe surgery. The surgery involves cleaning out any debris (cartilage fragments, etc.) that might be found in the great toe joint and repairing the torn plantar plate or plantar capsule at the base of the great toe. Recovery can be prolonged and often involves 6-8 weeks of non-weight-bearing or limited weight-bearing to allow the capsular repair to heal, 6-8 weeks of controlled rehabilitation while still protecting the repair in a boot or stiff soled shoe, and 6-8+ weeks of increasing controlled sports-specific exercises. It is not uncommon for swelling to persist for many months. It is also not uncommon to have some residual symptoms even after a seemingly successful surgery. Unfortunately for some a severe turf toe injury could be a career ending injury.
For patients with established gout (?2 >2 attacks/year) who are between attacks, urate-lowering should be initiated to reduce the urate burden and the risk of both attacks and tophi. First-line agents include allopurinol and febuxostat, which block urate production by inhibiting the synthesis enzyme xanthine oxidase. A recombinant uricase enzyme (pegloticase) is FDA-approved for refractory patients and can lower urate dramatically. In contrast to targeting urate production, probenecid promotes urate excretion from the kidneys. All patients starting urate-lowering therapy must receive anti-inflammatory prophylaxis (usually colchicine) for 6 or more months, since urate lowering transiently increases the risk of gouty attack. The goal is to drive the serum urate level to <6.0 mgs/dL (lower to resolve tophi). Drugs promoting hyperuricemia, including diuretics, should be substituted out whenever feasible.
Risk factors for hallux rigidus include trauma to the an elevated first metatarsal and/or a supinated forefoot leading to dorsal jamming at the 1st MTP joint. Other factors contributing to the development of hallux rigidus have been proposed including: trauma to the first MTP joint, metabolic disorders, autoimmune disease, congenital disorders, and congenital anatomic variation of the foot or first MTP joint. Because most of the risk factors include uncontrollable or systemic diseases, The primary risk factors appear related to the inherent biomechanics of each patient therefore prevention may not be possible. However, wearing properly fitting foot wear with a stiff-sole that limits motion of the first MTP joint, along with maintaining a healthy weight, may help if in patients who are predisposed to develop hallux rigidus.
Patients with hallux valgus often have a positive family history. It is common for patients to have a first-degree relative who has had a bunion, flatfoot deformity, or significant clawing of their lesser toes. This is may be the biggest risk factor for developing a significant bunion deformity. Additionally, wearing Wearing tight or ill-fitting shoes may contribute to symptoms related to the hallux valgus deformity. Interestingly, there is equal incidence of hallux valgus in males and females in societies that do not wear shoes. However, in societies with western style shoes, the deformity is 3-15 times more common in females. , but evidence suggesting that shoe wear actually causes a hallux valgus deformity is surprisingly weak. Prevention of hallux valgus itself may not be possible, but exacerbation of symptoms and further deformity can be prevented by wearing stiff-soled shoes with wide toe boxes, toe spacers, and shoe inserts.
The main risk factor for disorders of the sesamoid is having a higher arched foot. People with high arches that may be predisposed to sesamoiditis may be able to prevent this by wearing properly fitting shoes with shoe inserts that reduce the stress on the sesamoids. Additionally, as sesamoiditis is often caused by increased intensity of exercise, predisposed individuals wishing to increase exercise regiments should do so slowly and ideally in less weight bearing activities such as swimming or biking.
According to Childs, risk factors for turf toe include participating in athletics on artificial turf fields, playing certain sports that predispose to the injury (football, soccer, basketball, wrestling, dancing, tennis, and volleyball), foot pronation, increased toe box flexibility, flat foot, hallux degenerative joint disease, and prior first MTP joint injury (PMID:16900075). Therefore, turf toe may be prevented by wearing shoes with a stiffer toe box sole and limiting the amount of play on artificial turf fields.
Bedside Clinical skills for the diagnosis of disorders of the great toe include the ability to take a detailed but focused history and perform a thorough musculoskeletal examination. More advanced skills include the ability to aspirate and/or inject joints (students should be able to aspirate easily accessible joints such as the knee under expert supervision), and to identify crystals in joint fluid (gout).