SLR - August 2022 - Amy Ross, DPM
Reference: Magnusson EA, Telfer S, Jackson M, Githens MF. Does a Medial Malleolar Osteotomy or Posteromedial Approach Provide Greater Surgical Visualization for the Treatment of Talar Body Fractures? J Bone Joint Surg Am. 2021 Dec 15;103(24):2324-2330. doi: 10.2106/JBJS.21.00299. PMID: 34644268.Level of Evidence: V
Scientific Literature Review
Reviewed By: Amy Ross, DPM
Residency Program: Creighton University – Phoenix, AZ
Podiatric Relevance: A variety of surgical approaches exist for access to talar body fractures. Medial malleolar osteotomy (MMO) and posteromedial approach (PMA) are common techniques used to evaluate the extent of talar body fractures. A surgical approach that offers the best visualization and application of stable internal fixation with the least amount of dissection to reduce patient morbidity is ideal. The authors evaluated and compared the above approaches using 3D scanning technology in regards to visualization of the talus and hypothesized incorporating universal distractor and gastrocnemius recession would allow for better visualization of talar body surface area.
Methods: A cadaveric study was performed consisting of five pairs of lower limbs (total of 5 MMO and 5 PMA). The PMA group had a universal distractor consisting of 5 mm Schanz pins in the tibia and calcaneus. Gastrocnemius recession (medial approach) was performed following application of the distractor. Data was gathered after application of the distractor as well as with addition of the gastrocnemius recession for visualization of the talus using a handheld 3D surface scanner (Sense; 3D Systems). The talus was dissected out and evaluated with a NextEngine Desktop 3D scanner. Observable surface area of the talus (cm2) was recorded for the following groups: MMO, PMA, PMA with distractor, PMA with distractor and gastrocnemius recession.
Results: The greatest exposure of talar body and dome was observed in the MMO group (mean value 11.2 cm2) followed by 9.9 cm2 in the PMA with addition of distraction and gastrocnemius recession. PMA with distraction was 8.3 cm2 and PMA alone was 6.7 cm2. Mean visualized surface area of the talus between PMA group and PMA with distraction and gastrocnemius recession was statistically significant (3.2 cm2 increase in visualization). Mean visualization was 1.6 cm2 greater with PMA group with distraction and gastrocnemius recession compared to PMA with distraction. No significant difference was found in total surface area of talus when PMA with distraction and with and without gastrocnemius recession was compared to MMO group.
Conclusions: The authors concluded MMO provided improved visualization of talar dome, anterior talar body and dorsal to plantar examination compared to PMA approach. MMO gave greatest exposure of talus, however it involved performing an osteotomy along with limited access to medial and lateral aspects of the subtalar joint and posterior facet when considering presence of plantar fracture fragments. PMA allowed access to place posterior to anterior lag screws through a low profile plate for coronal based talar body fractures and avoids performing an osteotomy. Anatomic structures at risk with this approach include neurovascular bundle, flexor hallucis longus tendon and Achilles tendon paratenon. Incorporation of an external distractor increases stress risers in the tibia and calcaneus. Incorporation of gastrocnemius recession should be heavily weighed when considering to assist with distraction in an non-elective setting secondary to risk of plantarflexor weakness. Choice of approach should involve evaluation of fracture pattern, soft tissue envelope and goals of the procedure.