Injectable therapy is an invaluable diagnostic and therapeu-tic tool for the sports medicine physician and orthopedic
surgeon.1 This article in the series “Injectable Therapy” in theanagement of Musculoskeletal Injuries, focuses on com-on foot and ankle disorders that are amenable to treatmentith injectable pharmaceuticals and orthobiologics. Despite
heir widespread and frequent use, there is little guidance ofnjectable treatments to the ankle and foot. We sought to notnly provide a technique guide for injecting various treat-ents into the ankle and foot but to also supplement thisith the current state of evidence-based practice and the
linical rational for such treatment modalities.Injectable pharmaceuticals include corticosteroids and
iscosupplementation with hyaluronic acid (HA). Cortico-teroids have been in use for decades to treat various disor-ers of the ankle and metatarsophalangeal joints (MTPJs)long with other inflammatory processes of the foot and as-ociated tendons (Table 1). Much of the evidence supportingts use is anecdotal and often supported with either kneeiterature or poorly designed trials that make it difficult torrive at definitive recommendations or conclusions. Simi-arly, the use of viscosupplementation has been used to treatrthropathy of the ankle; however, its effectiveness and du-ation of action often are called into question.2
Department of Orthopaedic Surgery, Rush University Medical Center, Chi-cago, IL.
Address reprint requests to Johnny Lin, MD, Department of OrthopaedicSurgery, Rush University Medical Center, 1611 W. Harrison St, Chicago,
Orthobiologics, such as platelet-rich plasma (PRP), aregrowing increasingly significant as a therapeutic modality inthe armamentarium in treating foot and ankle disorders.3
PRP is concentration of platelets derived from autologousblood that has a large amount of growth factors that mayserve as an adjunct to or reestablish the healing process. PRPhas been investigated in multiple foot and ankle disorders(Table 2), but its clinical efficacy and recommendations re-garding its use have yet to be determined.
This article will focus on the pathogenesis, anatomy, anddiagnosis of specific clinical entities and how injectable ther-apy can be useful in practice.
Plantar FasciitisA common source for plantar heel pain, plantar fasciitiscauses 7% of all foot pain in the population aged 65 andolder4 and 25% of all foot disorders in the athletic popula-ion.5 The etiology of the disease is multifactorial and may be
because of repetitive microtrauma to the plantar fascia, whichcauses periostitis and microtears of the origin of the plantarfascia. Reduced ankle dorsiflexion, high body mass index,and work-related weight bearing are independent risk factorsfor the development of this disease.6
DiagnosisPlantar fasciitis is characterized by pain under the heel andmedial sole of the foot. Patients describe a pain that is most
noticeable with initial steps after prolonged immobilization
(ie, in the morning on waking up) or after long periods ofweight bearing. It is often a clinical diagnosis that may beconfirmed with magnetic resonance imaging (MRI) or ultra-sonography. On physical examination, patients will havepain with palpation of the origin of the plantar fascia (medialplantar heel). Examination sensitivity is increased with thetoes and ankle in dorsiflexion, which causes stretching of thefascia.
TreatmentAlthough plantar fasciitis is a self-limiting disease that usuallyresolves after 1 year, there are many interventions that can usedto help reduce the duration of the disease. Nonsteroidal anti-inflammatory medications (NSAIDs), night splint, stretchingexercises, over-the-counter heel cups, and extracorporealshock-wave therapy are initially used. If these fail to bringabout relief, injections are usually used.
Corticosteroid Injection:Considerations and TechniqueCorticosteroid injections are used in recalcitrant cases of plantarfasciitis. Methylprednisolone and hydrocortisone are often usedfor their solubility and short/medium duration of action.7 Theefficacy of steroids is hotly debated because the latest Cochranereview of the treatment of plantar heel pain was withdrawn.That review concluded that injectable therapy provides short-term and minor pain relief at best.8 Side effects include fat padatrophy, plantar fascia rupture, skin pigmentation, peripheralnerve injury, and postinjection flare.9
The patient is placed in lateral decubitus position with theaffected side down. The physician then localizes the origin of
able 1 Location and Associated Pathologies That can bereated With Corticosteroids
the plantar fascia at the medial aspect of the plantar foot, justdistal to the calcaneus. Often, the patient can help the phy-sician by localizing the area of maximal tenderness. The in-jection may now proceed under ultrasound guidance or bypalpation of the fascia.
The site is then prepared in the usual sterile fashion. A10-mL syringe (containing a mixture of local anesthetic andcorticosteroid) and a 25-gauge 1.5-inch needle is insertedperpendicular to the skin to a point past the midline of thewidth of the plantar foot (Fig. 1). The corticosteroid is thenevenly injected through the middle third of the width of thefoot as the needle is withdrawn. Another technique used byclinicians involves “peppering” the fascia with multiplepulsed injections through the same introduction site.
The patients can immediately weight bear, but shouldavoid strenuous activity for at least 48 hours. Patients may bewarned that they may experience a 24- to 48-hour–long ex-acerbation of their symptoms; however, this steroid flair usu-ally resolves with ice and NSAIDs.
Platelet-Rich PlasmaPRP has been recently studied in the use of plantar fasciitis.Barrett and Erredge10 showed in a small series that 6 of 9patients had resolution of symptoms within 2 months with77.9% of patients having no symptoms at 1 year.
The protocol for PRP injections varies depending on thesystem used.
The site and method of injection is described earlier, ex-cept that one will “pepper” the fascia with PRP to incite a localinflammatory response. The postinjection protocol also dif-fers.3 Patient is placed in a walking boot and not allowed to
ear weight for 7 days. After that, they may weight bear in thealking boot for 2 to 3 weeks. The patient’s activity is then
llowed to gradually progress over the next 3 weeks. At 6eeks, the patient’s progress is evaluated. If there is no re-
ponse to therapy, another injection may be given.
Tarsal Tunnel SyndromeTarsal tunnel syndrome is a compression syndrome of theposterior tibial nerve in the tarsal tunnel, formed by the me-
Figure 1 Medial approach to inject the plantar fascia.
dial malleolus and flexor retinaculum. This compression may
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Management of musculoskeletal injuries 187
be caused by any number of space-occupying lesions in thetunnel, an accessory flexor digitorum longus, medial malle-olus exostosis, or hindfoot valgus deformity.
DiagnosisPatients with tarsal tunnel syndrome will often complain of aburning, radiating pain, and paresthesias along the courseand distribution of the posterior tibial nerve. This pain isoften exacerbated with weight bearing or extremes of dorsi-flexion. The physician may also elicit a Tinel’s sign by tappingthe tarsal tunnel with subsequent pain in the medial one-third of the distal plantar foot. An electromyogram is oftenhelpful in diagnosis, as 81% of patients will have an abnormalelectromyogram,11 which is described as prolonged latenciesin the abductor hallucis and abductor digiti quinti.
TreatmentInitially, a treatment program consists of NSAIDs, rest,stretching, and the use of shoe inserts/orthotics that try toovercome foot pronation. Injection with corticosteroids maybe both useful diagnostically and therapeutically, although ifa space-occupying lesion was present in the tunnel, the reliefprovided by the injection will be ultimately short lived.
TechniqueThe patient is placed in the lateral decubitus position withthe affected foot down. One then identifies the point ofinjection behind the medial malleolus that is aggravatedby the Tinel’s sign. The physician should then ask thepatient to invert the foot against resistance to identify theposterior tibialis tendon, as the nerve lies immediatelyposterior to the tendon. Additionally, one should palpatethe posterior tibial artery, as the nerve lies directly poste-rior to the artery.
A needle angled 30° to the skin and directed distally isthen introduced 1 or 2 fingerbreadth distal to the identi-fied location. Again, the posterior tibial artery is then pal-pated and the needle directed posterior. The physicianshould note that the injection will be rather superficial andaspiration before injecting pharmaceutical to avoid entryinto an artery or vein. The steroid is then injected slowly.
Postinjection protocol includes protected weight bearingin a walking boot for 1 week followed by activities of dailyliving as tolerated in a regular shoe. No sport activity for 4weeks.
Ankle ArthritisArthritis of the ankle affects between 6% and 13% of allpatients with osteoarthritis.12 In addition to degenerativeoint disease, rheumatoid arthritis, and posttraumatic arthri-is can affect the ankle. Patients may also have a history ofrystalloid deposition disease.
DiagnosisPatients with arthritis of the ankle may describe anterior an-
kle pain with weight bearing or during push off. On physical
examination, they may have decreased flexion arc and mayreport pain during range of motion. Radiographs of the ankleare sufficient to identify the joint space narrowing that ischaracteristic of degenerative joint disease.
Treatment and Clinical ResultsCorticosteroids and viscosupplementation are commontreatment modalities after NSAIDs, activity modification,rocker sole shoes, and bracing fail. Corticosteroids have beenshown to significantly improve pain up to 6 months, withresponse to injection at 2 months to indicate response at 1year.13 HA can also be used to aid in the treatment of anklerthritis. Recently, a study involving 3 weekly injections ofA into the ankle provided significant pain relief, improvedalance, and decreased acetaminophen intake 6 months afterhe completed treatment.2 However, another study was justs quick to disprove HA from providing any significant reliefs compared with saline injections.14 No recent studies havehown the effect of PRP in ankle osteoarthritis, but recentnimal studies show that PRP can help form new cartilagend bone in osteochondral lesions.15 In vivo studies involv-ng the knee have shown significant pain decreases at 6
onths after injection.16
TechniqueA contraindication to the injection of any joint is the presenceof infection. If joint infection is not suspected, the patient isplaced supine with the foot 90° in relation to the leg (Fig. 2).The ankle is relaxed, and the articulation between the talusand the tibial plafond is noted. The tibialis anterior tendon isthen identified by asking the patient to dorsiflex the ankle.The space immediately medial to the tibialis anterior tendonand lateral to the medial malleolus is marked.
Sterile technique is absolutely necessary as to preventbacterial seeding of the joint. A 22-gauge 1.5-inch needleis then directed posterolaterally from the medial malleolus(Fig. 3). The needle must be aspirated as to not inject intoany artery or vein. Reduced resistance is felt on enteringthe joint space through the capsule. Confirmation of en-
Figure 2 Medial approach to inject the tarsal tunnel. Note that the
needle is directed 30° to the skin and directed laterally.
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188 C.E. Gross and J. Lin
tering the joint is made with a flash of synovial fluid withaspiration.
After injection care includes protected weight bearing in awalking boot for 1 week followed by activities of daily livingas tolerated in a regular shoe. No sport activity for 4 weeks.
Morton NeuromaMorton neuroma is an extremely frequent cause of forefootpain and disability. Morton neuroma is a paroxysmal neural-gia that presents as a sharp burning pain in the web spacemost commonly involving the third and fourth toes (80%-85%).17 It is not a neuroma in the formal definition of the
ord, but rather a perineural fibrosis.The epidemiology of the disease is not clearly defined, as
he incidence and prevalence are not known.18 Typically,women aged 45 to 50 years are affected. Although men areaffected, women account for the overwhelming majority.19
Both feet are equally affected, Although bilateral complaintsare rare. It is also uncommon to find 2 neuromas in the samefoot.
DiagnosisThe diagnosis of a Morton neuroma is a clinical one. A patientwith a Morton neuroma often complains of a burning sharppain that is located in between the third and fourth toes. Thispain is often plantar at the metatarsal heads and radiatesdistally on either side of the toe. It can often radiate from theforefoot up the leg proximally. It is exacerbated with wearingtight or constricted shoes and alleviated while walking bare-foot.
On physical examination, a useful test for Morton neu-roma is the “lateral squeeze test.” This test is performed withthe index and thumb on the dorsal and plantar aspect of thepainful intermetatarsal space. The plantarly placed thumbthen directs a dorsal force on the area of suspected neuroma,hoping to bring it between the metatarsal heads. The forefoot
Figure 3 Approach to injecting the ankle joint. Note the tibialisnterior, medial malleolus, and joint line are all marked.
is then compressed with the opposite hand by squeezing
together the metatarsal heads. The test is positive if a painfulor palpable click is felt. This “Mulder’s click” is likely becauseof subluxation of the neuroma between the metatarsalheads.20
TreatmentThere is no agreed-upon treatment algorithm, but most be-lieve that these treatments should be tried from 3 months toa year.17,21 Patients should be instructed to wear wide com-ortable shoes with large toe boxes.17 A trial of NSAIDs may
be used if there are no contraindications in attempt to de-crease the neuroma pain and inflammation. Physical therapyhas also been used.22 Ultrasound, whirlpool, massage, andlectrical stimulation are often used, although their efficacyas not been studied.
Corticosteroid and Injection TherapyAnother treatment modality is an intermetatarsal corticoste-roid and local anesthetic injection. Although some studiesshow that 47% of people may experience relief with injec-tions,23 others fail to show any long-term relief.24 Recently,tudies have looked at injection of either phenol or alcohol.n electrode-guided injection of phenol proved to be effec-
ive in 80.3% of cases.25 Ultrasound-guided injection of al-ohol gave 84% of patients total relief and partial relief to4%.26 Surgery is a last resort.
TechniqueThe patient is placed in a supine position with the foot re-laxed. The patient may find it comfortable to have his kneeflexed, supported with a pillow. The patient will then attemptto reproduce the area of pain in between the metatarsalheads. The area of tenderness is marked.
The injection proceeds with the needle directly at a 45°angle to the surface of the dorsal foot (Fig. 4). It is imperativethat the needle traverses the intermetatarsal ligament to enterthe bursa and infiltrate the neurovascular bundle. Oneshould feel a give after penetrating the aforementioned liga-ment. Another concern is not to inject too plantarly becausefat pad atrophy can occur. Follow-up care includes protected
Figure 4 Approach to injecting for a Morton neuroma. The needle is
directed 45° to the skin and directed posteriorly.
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Management of musculoskeletal injuries 189
weight bearing in a postoperative shoe for 1 week followed byactivities of daily living as tolerated in a regular shoe. Nosport activity for 4 weeks.
Hallux RigidusArthritis of the first MTPJ, or hallux rigidus, is an extremelycommon condition that affects �2.5% of all adults older than50.27 The disorder is characterized by pain and reducedange of motion in the first MTPJ. Its etiology is unclearecause most cases are idiopathic, although some cases arelearly secondary to distant trauma or crystalline depositionisease.28
DiagnosisPatients often complain of pain, swelling, and stiffness of thefirst MTPJ that is exacerbated with weight-bearing activities.The decreased dorsiflexion is secondary to periarticular os-teophytes. These osteophytes can lead to shoe-wear irritationand may even compress the dorsal cutaneous nerve, whichmay lead to paresthesias.
Anteroposterior, lateral, and oblique radiographs mayshow osteophytes located at the dorsal margin of the firstmetatarsal head articulation. Other characteristic radio-graphic signs of arthritis are present, including: subchondralsclerosis, bony cystic changes, and joint space narrowing.These changes are graded radiographically into grade 1(mild), 2 (moderate), or 3 (severe).29
TreatmentConservative management includes activity modification,ice, and NSAIDs. Orthotics with increased forefoot rigiditythat limits MTPJ dorsiflexion may relieve symptoms. Often astiff-soled rocker bottom shoe or an extra-depth shoe with ametatarsal bar can be worn for comfort.
If conservation management fails, then one may proceedwith a corticosteroid injection. Surgery is undertaken if con-servative management fails.
Corticosteroid InjectionSolan et al29 concluded that the relief afforded by a steroidinjection and manipulation was based on the severity of ini-tial hallux rigidus radiographs. Patients with grade 1 changeshad relief for a median of 6 months, with one-third of thepatients requiring open surgery. Patients with grade 2changes had a median relief of 3 months with two-thirdsundergoing an open surgical procedure. Grade 3 patientsexperienced little relief from a steroid injection and all re-quired surgery.
TechniqueThe patient is placed supine with their knee flexed and sup-ported with a pillow. The foot is held in a relaxed position. Thefirst MTPJ is identified by passively flexing and extending thejoint. Distal traction and flexion of the hallux will assist in in-serting the needle into the joint (Fig. 5). The 25-gauge 1.5-inch
needle and syringe is then inserted on the dorsomedial or dor-
solateral surface at an angle of approximately 60 to 70° to theplane of the foot.30 The needle should also be pointed distally tohelp match the contour and slope of the joint. The needle maybe felt passing through the capsule. Once the needle is intracap-sular (as confirmed by aspiration), the anesthetic and corticoste-roid are injected. Postinjection care includes protected weightbearing in a postoperative shoe for 1 week followed by activitiesof daily living as tolerated in a regular shoe. No sport activity for4 weeks.
AchillesTendinopathy and RepairAchilles tendon pathologies are varied and their subsequenttreatment is even more wide ranging. Disorders of the Achil-les tendon range from overuse injuries characterized withinflammation and degeneration as well as acute and chronicruptures. On the spectrum of Achilles pathology, the degen-erative Achilles tendinosis lends itself most to treatment withan injection.
Achilles tendinosis is a noninflammatory degenerativecondition caused by age, microtrauma, or both.31 Etiologicfactors include hormone replacement therapy and hyperten-sion in women and obesity in both sexes.32 The degenerationusually occurs at the hypovascular watershed area locatedapproximately 2 to 6 cm proximal to the calcaneal inser-tion.33
DiagnosisThe initial stages of the disease can be asymptomatic. How-ever, because the pathology progresses, the patient oftennotes thickening and nodularity of the Achilles tendon, aswell as focal tenderness. Subjective complaints includesstart-up pain in the morning as well as reduced performanceduring sport activity due to pain.
On physical examination, patients will have a positivepainful arc sign, which is seen when the swelling of the Achil-les tendon moves with dorsiflexion and plantarflexion. Thepatient will experience most pain at the terminal range ofdorsiflexion.
Figure 5 Approach to injecting the first metatarsophalangeal joint.
Note that the joint is distracted by the opposite hand.
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Both ultrasonography and MRI are useful radiologic ad-juncts in confirming the diagnosis of tendinosis. Ultrasonog-raphy will identify hypoechogenic lesions with or withoutcalcifications.31 MRI findings include tendon thickening anddistortion of the normal tissue signal.
TreatmentFortunately, patients usually respond to conservative treat-ment measures. These measures include rest, activity modi-fications, a heel lift or pad, and in athletes, a correction intraining techniques. Physical therapy may also be useful andshould focus on eccentric heel cord stretching and gastroc-nemius/soleus complex strengthening. For the older less ac-tive patient, immobilization with a controlled ankle motionboot or an ankle/foot orthosis may be helpful.
Corticosteroid injections are not recommended given thenoninflammatory nature of the disease as well as complica-tions of decreased tendon healing and increased tendon rup-ture.31 NSAIDs may be useful if there is any associated peri-endonitis.
However, approximately 25% of patients do not respondppropriately to conservative measures and generally willave to undergo surgery.34 As a response to the lack of reso-
ution of symptoms with the earlier outlined conservativeeasures, many researchers and clinicians have began to
tudy the role of PRP in the treatment of Achilles tendinosis.n rat models, PRP has proven to enhance neovascularizationnd thus healing in tendon injuries.35 Gaweda et al36 created
a prospective study of PRP on 15 subjects with Achilles ten-dinosis. Patients at 18 months had significant improvementsin pain and function.
TechniquePRP from whole-blood collection is prepared per manufac-turer directions. At the site of tendon pathology, between 6and 10 mL of activated PRP is injected with a 25-gauge 1.5-
Figure 6 Lateral approach to injecting the Achilles tendon.
inch needle into approximately 5 involved tendon sites. The
needle is introduced laterally, in the sagittal plane with thepatient in prone position under ultrasound guidance (Fig. 6).The needle is inserted until it is just halfway past the midlineof the tendon and then injected. Another technique involvesusing pulsed 0.25-mL dosages of PRP to pepper and fenes-trate the tendon at multiple sites.3
Patients are then placed in a controlled ankle motion bootand made nonweight bearing for 1 week. The patient is thenallowed to walk in the boot from weeks 1 to 3. At 4 weeks, thepatient transitions to an athletic shoe and slowly increases theweight bearing activity.
ConclusionsThis article hoped to serve as a resource for the treatingclinician in addressing many pathologic conditions of thefoot and ankle. Injectable pharmaceuticals and orthobiolog-ics are used widely, but often without clear clinical indica-tions or directions. Careful considerations must be takenwhen deciding to what, where, and why to inject therapeu-tics.
AcknowledgmentsWe would like to thank Kelly McDermott in preparing thefigures for this manuscript.
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