TOPIC at 5 Years: Promising Pain Relief, Unanswered Questions About the Relationship Between Structural Changes and Symptoms

Hollander et al. report on a prospective, single-center series of 37 patients who underwent Talar OsteoPeriostic grafting from the Iliac Crest (TOPIC) for large, predominantly medial osteochondral lesions of the talus, with 33 patients included in the 5-year analysis. The median score for pain during walking on an 11-point scale improved from 7 preoperatively to 2 at 5 years of follow-up, with improvement also noted on the Foot and Ankle Outcome Score (FAOS) subscales and the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, and with computed tomography (CT) evidence of universal graft consolidation. Two (5%) of the 37 patients underwent conversion to arthrodesis, at 4 years and at 4 years and 9 months, with analysis showing a 94% rate of survival at 5 years. Notably, postoperative cysts were present in 87% of the 30 patients with a CT scan at 5 years, echoing prior observations that cysts are frequent after bone grafting or osteoperiosteal grafting, and yet inconsistently related to symptoms. What are the advancements here? This is, to our knowledge, the first prospective cohort with TOPIC outcomes beyond 2 years, building on the authors’ earlier 24-month results that established feasibility and short-term efficacy1. The long-term implication—durable, clinically meaningful pain reduction with low reported donor-site morbidity at the iliac crest—is important because many surgeons still default to transfer of osteochondral autograft from the knee to the ankle, fresh allograft, or (in some systems) primary arthrodesis for large osteochondral lesions of the talus. The authors also make a pragmatic point: the iliac crest’s curvature can better approximate that of the medial talar dome than can cylindrical plugs, and the periosteal cambium may aid chondrogenesis—mechanistic hypotheses that fit the observed consolidation. How do the findings fit into the treatment landscape? When they are viewed against alternatives, the patient-reported outcomes look competitive. An AOFAS score in the 80s at midterm has been reported for a series using fresh structural allograft2, with a comparable range observed in ankles treated with autologous chondrocyte implantation (ACI)3. Although cross-study comparisons are imperfect, the median AOFAS score of 87 at 5 years in the current study suggests that TOPIC belongs among joint-preserving options for large, complex osteochondral lesions of the talus—particularly in settings with constrained allograft availability or when surgeons wish to avoid knee donor-site morbidity4. A 5% conversion to arthrodesis also compares favorably with historical series of large, cystic lesions. Major strengths of this study include its: Prospective design with a predefined primary outcome and an a priori power calculation. Robust follow-up (100% clinical and 91% radiographic) at 5 years among those eligible. Consistent imaging schedule for documenting both early union and late structural changes. Key limitations and cautions in interpretation include: A level of evidence grade of IV, without a comparator group. The absence of randomization or matched controls limits inferences regarding the comparative effectiveness versus allograft, ACI, or staged approaches. Limited generalizability. The study was conducted at a tertiary, high-volume center, with procedures performed by 2 fellowship-trained surgeons; reproducibility across centers and learning-curve effects remain unknown. Outcome hierarchy. Pain during walking is clinically relevant, and the score exceeded the minimal clinically important difference (MCID), but the score for global health (the Short Form [SF]-36 Physical Component Summary) changed only modestly, and the score assessing sports participation (median score of 60 for the FAOS Sports subscale) did not normalize—important for younger, athletic patients. Radiation and hardware burden. Serial CT scans (preoperative to 5 years) result in a cumulative radiation dose, and 43% of the patients underwent screw removal. These practical concerns should factor into shared decision-making. Cysts: a consistent finding with unclear clinical meaning. The 87% cyst rate at 5 years underscores a structural change following TOPIC, but its trajectory and clinical implications remain undefined. Current meta-analytic data suggest a poor correlation of cysts with symptoms5, but late effects (progressive pain, graft fatigue, or adjacent bone changes) need longer-term surveillance and standardized cyst grading to enable pooled analyses. Clinical Takeaway For large, medial osteochondral lesions of the talus—especially non-primary or cystic lesions—TOPIC offers a joint-preserving option in expert hands, with durable midterm pain relief, reliable consolidation, and minimal patient-reported iliac crest morbidity. Surgeons should counsel patients that (1) function improves but may not fully normalize, (2) cysts on CT are common and not necessarily a failure of treatment, and (3) the evidence remains noncomparative. What’s next? Multicenter, comparative effectiveness studies (TOPIC versus fresh allograft versus ACI), with common patient-reported outcome measures, standardized CT/MRI (magnetic resonance imaging) cyst taxonomy, radiation-minimizing imaging protocols, and the time to arthrodesis or other operation as hard end points, would clarify patient selection. Cost-effectiveness modeling that incorporates imaging and reoperation for hardware removal would further inform policy and practice.