Osteochondral lesions of the talus(OLT), also commonly known as osteochondral defects (OCD) of the talus, is alesion involving the bone’s cartilage and subchondral bone that may break offpartially or completely from the talus.
1 Articular cartilage is atissue with poor reparative capability that surrounds the talus.2 After the elbow and knee, thetalus is the third-most common area where OLTs may occur.3 These lesions may transpireon the medial or lateral side of the talus.4 Osteochondral lesions of thetalus occur more frequently with traumatic injuries1,3,5,6 , accompanying up to 70-85%of ankle sprains and fractures.3,5 They could follow a singletraumatic injury, or after multiple traumatic injuries.3,6 However, non-traumatic etiologymay lead to OLT as well including but not limited to, “congenital factors,ligamentous laxity, spontaneous necrosis, endocrine abnormalities, steroid use,and embolic disease.”5 Osteochondral lesions of thetalus are more common in the male population, as well as the age range of 20-30years.
4Osteochondrallesions of the talus may present as deep ankle pain that may or may not persistafter an ankle sprain.1,6,7 The pain can be exaggeratedduring weight bearing activities, including daily life, work, and recreationalactivities.1,7 The patient may experiencethe sensation of their ankle giving way, catching, locking, and clicking.
1,7 On a physical examination,swelling, medial or lateral tenderness, lack of range of motion (ROM), andinstability may be present.1,7 The main complaints patientshave include pain and their overall decrease of function.8Osteochondrallesions of the talus can be easily overlooked, especially when accompanied byconcurrent injury including ankle sprains.4,9 There are no specificphysical examination tools that may indicate to a clinician that a OLT may bepresent.10 Additionally, diagnosis canbe delayed because plain radiographs appear normal.7,9 Gianakos et al. report that”up to 50% of OLTs are missed on plain radiographs”.
10 Osteochondral lesions of thetalus are more commonly diagnosed later when conservative treatment fails, and painand other symptoms persist.1,3Additional imaging is neededincluding, magnetic resonance imaging (MRI), computed tomography (CT) scans,and bone scans to accurately diagnose OLT.1,4 Bone scans can rule out occultfractures,1 while CT scans are used tolocate the region of the lesion, and MRIs detect actual cartilage damage.1,4 Thereare numerous treatment options for OLT, however research is still beingperformed to find the ideal treatment option.3 The most common treatmentoptions include conservative, or surgical intervention.3–5,8 Conservative treatment usuallyinvolves, immobilization or bracing, weight bearing precautions, activitymodifications, non-steroidal anti-inflammatory medications (NSAIDs),corticosteroid injections, and physical therapy.3,5,8,11 Conservative treatmentresults are variable.
8 Savage Elliot et al. foundthat in conservative treatment, there was good to excellent results in only 54%of their patients diagnosed with cystic OLTs.4 Badekus et al report a 45%success rate for conservative treatment3 while Hannon et al. reports astudy finding 49.1% success rate with conservative treatment.
5 Symptoms may resolve fromconservative treatment for the short term, however OLTs can reoccur due to theinsufficient healing of the lesion.5Where conservativetreatment failed a surgical intervention would then be recommended.3 A surgical intervention is aninvasive approach to promote healing and resurfacing of the articular cartilage.The choice of which surgical intervention to use depends on the size of thelesion, and if there is a cyst present.5 Smaller lesions are definedas lesions that are smaller or equal to 15 mm in size, where larger lesions aredefined as greater than 15 mm in size.
1 The preferred treatmentoptions for small lesion OLTs include subchondral drilling and microfracture.1,4–6,8,12 Drilling and microfracturestimulates the subchondral bone to promote chondral healing through aninflammatory response to micro trauma.8,12 Ventura et al. explains the advantagesto these surgical interventions stating that they “minimize invasiveness,decrease operating time, and allow a faster rehabilitation period and anearlier return to work”.11 When using these surgicaltechniques, studies account for good short term results, yet the long termresults are unknown.
6Pain and decreasedfunction are commonly the patient’s main complaints with OCL and reasons forwhy patients seek out surgical intervention.8 The goal of surgicalintervention is to decrease that pain and get their patient to return tofunction or activity.3,5 Return to activity can bedefined as decease in pain with movement and return to previous recreationalactivities.4 Standardized outcome toolscan measure return to activity and pain ratings following a surgicalintervention.6,7,11–13 The optimal outcome tool touse following an ankle or foot intervention is unknown.14 Outcome tools that are seenin research are, but not limited to, the American Orthopedic Foot and AnkleSociety (AOFAS) ankle-hind foot scale, the visual analog scale (VAS), ankleactivity scale (AAS), Karlsson Peterson score, Tegner activity level, and theSefton articular stability scale.6,7,11–13 The AOFAS ankle-hind footscale has 4 categories including pain, function and alignment.
14 The scale is out of 100 and ascore greater than or equal to 90 points is considered excellent, 80-89 isconsidered good, 70-79 is considered fair, and a score of less than or equal to69 is considered poor.12 SooHoo et al performed astudy looking at the responsiveness of the AOFAS scale following foot and anklesurgery, and it was found that this outcome tool has an acceptable responsivenessto clinical change.14 To measure the responsivenessof this outcome tool, they studied its effect size, which equaled 1.12.
14 The VAS is a scale thatallows a patient to quantify how much pain they are experiencing on a scalefrom 0-10.12 The AAS is a 10-point scalethat is used to assess a patients activity level, which was developed by theTegner scoring system.12 The AOFAS ankle-hind footscale and the VAS were the two more commonly seen tools in the literature.6,7,11–13The purpose ofthis research was to determine if return to activity was achievable following asurgical intervention for a small OCL of the talus. The patient who inspiredthis research was diagnosed with this pathology and expressed concern aboutreturning to his recreational activities. This required research to locatepossible surgical interventions that may relate to our patient, and todetermine whether or not these interventions would allow return to activity.Therefore this research focused on outcomes of surgical interventions for OCLof the talus.