Pertinent Insights On Treating Second MPJ Pathology
What You Should Know About Imaging And Ancillary Tests
Initial imaging should start with a standard radiographic evaluation including weightbearing AP, lateral and medial oblique views. In certain instances, a sesamoid axial view may be beneficial in visualizing pressure distributions under the metatarsal heads. Long leg axial views can additionally demonstrate lower extremity positioning.
On AP radiographs, one should assess the metatarsal parabola, first MPJ congruity, intermetatarsal angle, second MPJ space congruity and overall shape of the metatarsal heads. On lateral views, evaluate digital contractures, metatarsus primus elevatus and metatarsal declination angles. Consider serial radiographs spaced between appointments to check for articular changes and second metatarsophalangeal joint deviation.
Researchers have shown that longitudinal ultrasound imaging identifies plantar plate tears better in comparison to contralateral non-affected feet. Ultrasound has a sensitivity of 91.1 percent and specificity of 25 percent.3 One may also use joint arthrography to evaluate for plantar plate tears. Although clinicians usually use magnetic resonance imaging (MRI) for confirmation, it is also effective in identifying early osteochondral changes to the joint to assist in validation of a plantar plate tear. Studies are reporting sensitivity and specificity as high as 95 percent and 100 percent respectively with the use of MRI in identifying plantar plate tears.4
Conservative Care Options For The Second MPJ
Physicians should always exhaust conservative approaches as a first line of treatment before mentioning surgical intervention. Placing metatarsal pads proximal to the metatarsal heads can provide the offloading that is needed in cases of synovitis or capsulitis. In addition, splinting or taping the second toe into a reduced position may provide some temporary relief of symptoms at the affected joint. Silicone gel toe sleeves can relieve pressures on dorsally contracted digits that are prominent and aggravated by shoe gear.
Wide toe boxes, decreased heel heights and rocker bottom shoes are simple shoe gear modifications that one can attempt with an early deformity to slow its progression. Partial or complete offloading in a fracture boot can assist in cases of Freiberg’s infraction to treat symptoms of pain and acute inflammation. Non-steroidal anti-inflammatory drugs can also be a safe first-line treatment in alleviating inflammation at the second MPJ. The use of corticosteroids, both systemically and as an intra-articular injection, is controversial. Multiple authors have documented a prevalence of decreased ligamentous structure strength after intra-articular injection of corticosteroids.5-7 Reserve the use of intra-articular corticosteroid injections for the most severe and recalcitrant cases.
Essential Surgical Considerations
After exhausting conservative modalities, one can discuss surgical intervention as the next line of treatment. Making the correct diagnosis and determining the appropriate etiology of the second MPJ pathology are critical to formulating surgical plans for correction.