Central Metatarsal Fractures

Dan Preece DPM, PGY-1

Stress Fx Frequency /Distribution:

-second metatarsal 52%-third metatarsal 35%-first metatarsal 8%-fourth and fifth metatarsals 5%

**shorter first metatarsal of Morton's foot leads to a higher risk of second metatarsal stress fractures

2: Leabhart J: Stress fractures of the calcaneus. J Bone Joint Surg Am 41:1285-1290, 1959.

1: Drez D Jr, Young J, Johnston R, Parker W: Metatarsal stress fractures. Am J Sports Med 8:123-125, 1980

Factors that can increase the risk of fractures (and stress fractures:

-cavus foot conformation-long second metatarsal (e.g. Morton's foot)-metatarsus adductus-amenorrhea (hypoestrogenism)-hyperthyroidism-osteoporosis -medications -tobacco -alcohol abuse -nutritional problems-anemic disorders-training errors-poor footwear-improper athletic technique

3: Daffner R, Pavlov H: Stress fractures: Current concepts. Am J Radiol 159:245-252, 1992.

Etiology and Description of Stress Fractures:

- Microfractures Stress Reactions Cortical Fracture.

- Stress fxs occur by cyclic loading that does not exceed the ultimate

breaking limits of plastic deformation of bone.

- One possible cause of stress fracture is muscle fatigue, which decreases shock-absorbing capacity of the extremity.

- Repetitive force exerted by a muscle on bone

3: Daffner R, Pavlov H: Stress fractures: Current concepts. Am J Radiol 159:245-252, 1992.

Biomechanical Causes of Metatarsal Stress Fxs:

-Dorsal strains are significantly reduced by contraction of the plantar flexory musculature.

- Fatigue of these muscles during strenuous or prolonged running may result in decreased dissipation of forces by the musculature and increased exposure of the metatarsals to stress.

4: Brukner P, Bradshaw C, Khan KM, et al. Stress fractures: a review of 180 cases. Clin J Sport Med. 1996;6(2):85–9.

Clinical Presentation of Stress Fxs:

- Metatarsal stress fxs have a much faster onset than similar injuries of the tibia and fibula.

- The average time to presentation ranges from 2 to 6 weeks

- Can occur with a single training event or military exercise.

- Pain to direct palpation and through ROM, also pain, redness, swelling present.

5: Milgrom C, Finestone A, Sharkey N, et al: Metatarsal strains are sufficient to cause fracture during cyclic loading. Foot Ankle Int 23(3):230-235, 2002

Stress Fractures: - Imaging:

-Plain films may not show changes for > 10 days. Changes may be evident in only 30% to 70% of cases.

-Bone Scan: 99Tc bone scan is extremely sensitive, and uptake may be evident within 24 hours of injury (not specific however) .

-MRI is highly sensitive and specific, particularly to identifying location.

-CT is helpful to define a fx line and to determine whether the fx is complete or incomplete.

6: Matheson G, Clements D, McKenzie D, et al: Stress fractures in athletes: A study of 320 cases. Am J Sports Med 15:46-58, 1987.

-Forty-one feet were analyzed with US and dedicated MRI from 37 patients.

-MRI detected 13 fractures in 12 patients.

-US was 83% sensitive, 76% specific. Positive predictive value 59%, and negative predictive value 92%.

-In cases of normal radiographs, US is indicated in the diagnosis of metatarsal bone stress fractures, as it is a low cost, noninvasive, rapid, and easy technique with good sensitivity and specificity.

US in Dx of Stress Fractures:

7: F Banal, F Etchepare, B Rouhier, C Rosenberg, V Foltz, S Rozenberg. Ultrasound ability in early diagnosis of stress fracture of metatarsal bone. Ann Rheum Dis. 2006 July; 65(7): 977–978.

Stress Fx Treatment: -Activity restriction 4-8+ weeks.

-Immobilization: depends on the duration of symptoms before the patient presenting for treatment. Longer duration: more severe injury.

-Serial radiography used to document bony union.

-Correct contributing factors : training techniques and footwear.

-Return to activity is allowed when radiographic healing is noted and tenderness has completely resolved.

-Recurrent stress fractures are uncommon in the absence of metabolic or endocrine disorders, and they rarely recur at the same site

8: K, Hahn S, Chung M, et al: A clinical study of stress fractures in sports activities. Orthopedics 15:1089-1095, 1991.

Metatarsal Fx’s:

-Frequency: 5th 3rd 2nd 1st 4th (different frequency than stress fx’s)

-MCC: -Direct force: crushing, blunt trauma, penetrating wounds. -Indirect force: twisting injury (forepart of the foot is fixed as the pt turns)

-Who? Most commonly: athletes, diabetics (worse with longer duration), men.

-Diabetic neuropathy: has been associated with osteopenia in both hands and feet as well as metatarsal fxs.

10: DeLee JC, Evans JP, Julian J. Stress fracture of the fifth metatarsal. Am J Sports Med 1983;11:349-353.

9: Sammarco GJ: The Jones fracture. Instr Course Lect 42:201-205, 1993.

16: Cundy, TF, Edmonds, ME, Watkins, PJ. Osteopenia and metatarsal fractures in diabetic neuropathy. Diabet Med 1985; 2:461.

A 6-month study showed that metatarsal fractures accounted for (majority are 1st and 5th met fx):

35% of foot fractures, 6% of foot injuries, 5% of skeletal fractures,

0.2% of emergency department visits.

11: SPECTOR FC, KARLIN JM, SCURRAN BL, ET AL: Lesser metatarsal fractures: incidence, management, and review. JAPA 74: 259, 1984.

Unstable Foot Types Leads to Stress Overload: hypermobile 1st and/or 5th rays causes overload of the lesser mets.

GRFGRF

Surgical Approach: consider the complex soft tissue anatomy that surrounds, inserts or originates from each of the central metatarsals.

-Fractures of the proximal shaft and base must be evaluated for ligamentous disruption.

- Manipulation under anesthesia while monitoring with fluoroscopy is recommended.

Fracture Treatment Options:

-Non-dislocated fractures w/o ligament damage of the second, third, and fourth metatarsal bases rarely need treatment other than solid-soled shoe or, if painful, a cast.

-Met fxs are often held in good alignment by surrounding ligamentous structures, with exception of met neck and shaft fractures that displace easily.

-3 to 4 mm of medial or lateral transverse plane deformity and 10° or less of angulation are well tolerated and need not undergo surgical corrective measures.

-Healing time may be as much as 3 months from injury.

-Weight bearing is advanced as tolerated.12: Armagan OE, Shereff MJ. Injuries to the toes and metatarsal. Foot Ankle Trauma. 2001;32:1–10.

Fracture Tx Options:

-ORIF is indicated in metatarsal fractures that are irreducible, involve a joint, or are significantly displaced.

Fixation options: -crossed K-wires,

-percutaneous pinning, -circlage wire, -interfrag screw, -plate and screw fixation, -external fixation, -intramedullary fixation using a Steinmann pin or double-

threaded compression screw .

13:Rammelt S, Heineck J, Zwipp H. Metatarsal fractures. Injury. 2004;35:S-B77–S-B86.

14: Pendarvis JA, Mandracchia VJ, Haverstock BD, et al. A new fixation technique for metatarsal fractures. Clin Podiatr Med Surg. 1999;16:643–657

Evidence for which type of fixation is best in lesser met fractures:

-None -Didley Squat -Zilch

*Best evidence available is “author’s experience”.

*Most authors recommend k-wire/steinman pins or other types of intramed fixation.

Evidence from osteotomies similar to met fractures:

-40 bone models were divided equally into 4 groups: a control group consisting of intact lesser rays; and Weil osteotomies that were fixated with 2 crossed Kirschner wires (0.045-in K-wires), 2.0-mm cortical screws, or cannulated 2.4-mm cortical screws.

Result: There was no statistical difference in structural stiffness among the 3 groups of fixation methods.

20: Craig T. Jex, DPM,1 Chanda J. Wan, DPM,2 Steve Rundell, MS. Analysis of Three Types of Fixation of the Weil Osteotomy. The Journal of Foot & Ankle Surgery 45(1):13–19, 2006.

K-Wire Pinning Technique: (same idea as hammertoe fixation)

K-Wire Fixation:

Fixation Options: k-wires

Comminuted Fxs:

-Kirschner wire for provisional stability.

-Application of mini external fixation devices to the fourth and fifth metatarsal fractures.

15: I, Mosheiff R, Zelgowski A, et al. Crush injuries of the foot with compartment syndrome: immediate one-stage management. Foot Ankle. 1989;9(4):185–

189.

IM Rod Fixation

Fixation Options:

Fixation Options: plate and screws.

Fixation Options: k-wires, plate and screws.

Complications to be aware of:

Significant shortening or angular deviation of mets-may result in transfer lesions/pressure points/new stress

fx

Early weight bearing with unstable fixationnon unions

Pin tract infection vs irritation, hematoma, seroma etc.

References:

1: Drez D Jr, Young J, Johnston R, Parker W: Metatarsal stress fractures. Am J Sports Med 8:123-125, 1980.

2: Leabhart J: Stress fractures of the calcaneus. J Bone Joint Surg Am 41:1285-1290, 1959.

3: Daffner R, Pavlov H: Stress fractures: Current concepts. Am J Radiol 159:245-252, 1992.

4: Brukner P, Bradshaw C, Khan KM, et al. Stress fractures: a review of 180 cases. Clin J Sport Med. 1996;6(2):85–9.

5: Milgrom C, Finestone A, Sharkey N, et al: Metatarsal strains are sufficient to cause fracture during cyclic loading. Foot Ankle Int 23(3):230-235, 2002

6: Matheson G, Clements D, McKenzie D, et al: Stress fractures in athletes: A study of 320 cases. Am J Sports Med 15:46-58, 1987.

7: F Banal, F Etchepare, B Rouhier, C Rosenberg, V Foltz, S Rozenberg. Ultrasound ability in early diagnosis of stress fracture of metatarsal bone. Ann Rheum Dis. 2006 July; 65(7): 977–978.

8: Ha K, Hahn S, Chung M, et al: A clinical study of stress fractures in sports activities. Orthopedics 15:1089-1095, 1991.

9: Sammarco GJ: The Jones fracture. Instr Course Lect 42:201-205, 1993.

10: DeLee JC, Evans JP, Julian J. Stress fracture of the fifth metatarsal. Am J Sports Med 1983;11:349-353.

11: Spector FC, Karlin JM, Scurran BL, et al: Lesser metatarsal fractures: incidence, management, and review. JAPA 74: 259, 1984.

12: Armagan OE, Shereff MJ. Injuries to the toes and metatarsal. Foot Ankle Trauma. 2001;32:1–10

13: Rammelt S, Heineck J, Zwipp H. Metatarsal fractures. Injury. 2004;35:S-B77–S-B86.

14: Pendarvis JA, Mandracchia VJ, Haverstock BD, et al. A new fixation technique for metatarsal fractures. Clin Podiatr Med Surg. 1999;16:643–657

15: I, Mosheiff R, Zelgowski A, et al. Crush injuries of the foot with compartment syndrome: immediate one-stage management. Foot Ankle. 1989;9(4):185–189.

16: Cundy, TF, Edmonds, ME, Watkins, PJ. Osteopenia and metatarsal fractures in diabetic neuropathy. Diabet Med 1985; 2:461.

17: Wolf, SK. Diabetes mellitus and predisposition to athletic pedal fracture. J Foot Ankle Surg 1998; 37:16.

18: S Papp, R Sanders. Fractures of the Midfoot and Forefoot. Surgery of the Foot and Ankle. 8th edition. Ch 41 pg 2215.

19: Craig T. Jex, DPM,1 Chanda J. Wan, DPM,2 Steve Rundell, MS. Analysis of Three Types of Fixation of the Weil Osteotomy.. JFAS 45(1):13–19, 2006.