Os Trigonum Syndrome

This is an extremely complex case that tests advanced understanding of os trigonum syndrome with significant flexor hallucis longus (FHL) pathology, bilateral disease management, and the unique considerations for an elite athlete whose career depends on optimal functional outcomes. There are several CRITICAL decision points. First, understanding the DUAL PATHOLOGY and their relationship: (1) OS TRIGONUM SYNDROME - she has bilateral os trigonum ossicles with bone marrow edema (RIGHT severe, LEFT mild) indicating active symptomatic impingement. The 'nutcracker' mechanism (compression between tibia and calcaneus during plantarflexion) is causing inflammation. (2) FHL TENDINOPATHY and STENOSING TENOSYNOVITIS - this is the cause of her TRIGGERING symptoms. The FHL tendon runs through a fibro-osseous tunnel between the medial and lateral tubercles of the posterior talus - the os trigonum is the LATERAL tubercle (or adjacent to it). When the os trigonum is inflamed and enlarged due to chronic impingement, it can cause STENOSIS (narrowing) of the FHL tunnel. Additionally, chronic inflammation from os trigonum syndrome often causes secondary FHL tenosynovitis. The combination creates a 'trigger finger'-like mechanism where the thickened, inflamed tendon cannot glide smoothly through the stenosed tunnel. These pathologies are INTIMATELY RELATED, not separate - the os trigonum impingement is causing or exacerbating the FHL pathology. For SURGICAL PLANNING in the RIGHT ankle (dominant pathology): Both pathologies MUST be addressed in a single surgical procedure. Excising the os trigonum alone without addressing FHL stenosis will leave her with persistent triggering and pain. Conversely, FHL release without os trigonum excision leaves the impingement source. The surgery must include: (1) COMPLETE EXCISION of the os trigonum - remove entire ossicle (incomplete excision leaves painful remnant), (2) FHL SHEATH RELEASE (tenosynovectomy) - release the constricted fibro-osseous tunnel where the FHL is stenosed, remove inflammatory synovium around the tendon (tenosynovectomy), (3) INSPECTION and possible DEBRIDEMENT of FHL tendon - if there is significant tendinopathy with longitudinal splits or fraying, may need to debride the tendon. However, must be VERY careful not to excise so much tendon that strength is compromised (this would be catastrophic for a ballet dancer). (4) Ensure FHL glides FREELY after the above - test intraoperatively by passively moving the hallux through full range while visualizing the tendon. SURGICAL APPROACH - Endoscopic vs Open debate: ENDOSCOPIC technique (two-portal posterior ankle approach - van Dijk technique) is the STANDARD for os trigonum excision and can also address FHL release. However, when there is SEVERE FHL pathology requiring significant tendon work, some surgeons prefer an OPEN POSTEROMEDIAL approach which gives better visualization and access to the FHL. The decision depends on: Surgeon experience/comfort with endoscopic FHL work, Extent of FHL tendon debridement anticipated (if extensive tendon debridement needed, open may be safer to avoid over-resection). For this case, if the surgeon is experienced with endoscopic techniques, I would favor ENDOSCOPIC as it has faster recovery (critical for her 6-month timeline). However, if significant tendon debridement is needed, open may be more appropriate. This is a judgment call based on MRI findings and surgeon skill. For the LEFT ankle (milder pathology): The LEFT side has milder symptoms and milder MRI findings. The CRITICAL question is whether to operate on both ankles simultaneously (BILATERAL simultaneous surgery) or stage them (RIGHT first, LEFT later if needed). ARGUMENTS FOR STAGED approach (RIGHT first, LEFT later): (1) Bilateral simultaneous posterior ankle surgery requires BILATERAL non-weight-bearing which is very challenging for rehabilitation, (2) If there are complications on one side, at least the other side is unaffected, (3) The LEFT side is milder - may respond to continued conservative management once RIGHT side is fixed (she may be able to modify technique to offload LEFT side), (4) Allows her to focus rehabilitation efforts on one side for faster recovery. ARGUMENTS FOR SIMULTANEOUS bilateral surgery: (1) Single anesthesia/recovery period, (2) Get all pathology addressed in one surgery, (3) Return to dance at same time on both sides (no asymmetry), (4) Avoid need for second surgery if LEFT progresses. For an ELITE BALLET DANCER with a 6-month deadline, I would STRONGLY RECOMMEND a STAGED approach (RIGHT side first, assess LEFT later). Reasons: (1) Bilateral simultaneous surgery would delay return to dance significantly due to bilateral NWB requirements, (2) If any complications occur bilaterally, career could be over, (3) Fixing the dominant RIGHT side may be sufficient for her to perform (dancers often have some asymmetry), (4) Can reassess LEFT after RIGHT recovery - may be able to temporize with injections if needed to get through Swan Lake, then address LEFT in off-season. For TIMELINE to return to professional ballet after surgery: This is the CRITICAL question for her. REALISTIC timeline for RIGHT ankle surgery (endoscopic os trigonum excision + FHL release): Week 0-2: Non-weight-bearing in CAM boot, ankle ROM exercises, Week 2-4: Progressive weight-bearing, continue ROM, Week 4-6: Full weight-bearing, strengthening begins, Week 6-8: Progress to bilateral heel raises, proprioception training, Week 8-12: Running program, bilateral toe raises, ankle strengthening, Week 12-16: Return to dance-specific training (barre work, basic positions), Week 16-20: Progress to relevé (rising onto ball of foot), Week 20-24: GRADUAL return to en pointe work (extreme plantarflexion - this is the most demanding position for posterior ankle, must not rush this), Week 24-28: Return to full dance including jumping, turning, partnering work. REALISTIC return to PROFESSIONAL PERFORMANCE level: 6-8 MONTHS for full return to principal dancer level. This is LONGER than recreational ballet (4-6 months) because the demands are so much higher. She needs to be able to hold en pointe for extended periods, perform multiple fouettés, grand jetés, etc. - all of which place enormous stress on posterior ankle. For her SWAN LAKE performance in 6 months: I would be HONEST with her that this is a VERY TIGHT timeline and there is significant risk she will NOT be ready for professional performance at 6 months post-op, particularly for a principal role in Swan Lake which is one of the most technically demanding ballets. If surgery is performed NOW (Month 0), her timeline would be: Month 4 (Week 16): Just starting return to dance-specific training, Month 6 (Week 24): Just progressing to en pointe work, possibly not ready for full performance. OPTIONS to discuss: (1) SURGERY NOW, accept that she will likely MISS the Swan Lake performance, plan for return 8 months from now, (2) DELAY surgery until AFTER Swan Lake, manage conservatively (more injections, activity modification) to get through the performance, then have surgery with full recovery timeline. This is risky as she may not be able to perform even with conservative management, and delaying surgery risks worsening FHL pathology, (3) Consider if an UNDERSTUDY could perform the lead role while she performs a less demanding role in the production - compromise option. This is a SHARED DECISION - she needs to understand the realistic timelines and make an informed choice about her career priorities. For RISKS specific to FHL and ballet career: (1) FHL WEAKNESS - if too much tendon is debrided during surgery, can cause permanent weakness of hallux plantarflexion. This would be DEVASTATING for a ballet dancer as FHL is critical for en pointe stability and push-off. Risk minimized by conservative debridement (only remove clearly diseased tissue, preserve bulk), (2) FHL ADHESIONS - if the tendon scars down after surgery, can cause stiffness and loss of gliding. Prevented by early ROM exercises and ensuring complete release of stenosis at surgery, (3) INCOMPLETE RELIEF of triggering - if FHL stenosis not adequately released, triggering may persist. This is why thorough release and intraoperative testing of tendon gliding is critical, (4) NERVE INJURY - medial plantar nerve branch runs near surgical field (particularly for open posteromedial approach). Injury causes numbness on plantar medial foot. Rare with careful technique (less than 2%), (5) INFECTION, WOUND COMPLICATIONS - standard surgical risks (1-2%), (6) INCOMPLETE os trigonum excision - if any ossicle remnant left, can have persistent impingement. Must remove entire ossicle, (7) SCAR TISSUE/FIBROSIS - can cause posterior ankle stiffness limiting plantarflexion (ironic - surgery to improve plantarflexion pain could cause stiffness if significant scarring). Prevented by early mobilization. Regarding whether this could END her dancing career: I would be HONEST but BALANCED. The GOOD NEWS is that outcomes of os trigonum excision with FHL release in dancers are generally EXCELLENT - multiple series report 85-95% return to pre-injury dance level. The surgery is addressing pathology that is ALREADY limiting her career (she has triggering and pain affecting performances now). Without surgery, her symptoms will likely progress and she will be UNABLE to continue at principal dancer level. WITH surgery, she has an 85-95% chance of full return. The RISKS are: (1) Surgical complications (FHL weakness, adhesions, nerve injury) could limit function (5-10% risk of suboptimal outcome), (2) Even with successful surgery, some dancers find they don't quite return to their absolute peak form (subtle proprioception changes, confidence issues), (3) Recovery time is long (6-8 months) which in the ballet world could mean missing critical performance opportunities. OVERALL, I would frame this as: Surgery gives her the BEST chance of continuing her professional ballet career long-term, but she needs realistic expectations about timeline (likely miss Swan Lake) and a small risk of suboptimal outcome. WITHOUT surgery, she is ALREADY on a trajectory to end her career due to progressive symptoms. RECOMMENDATION: (1) RIGHT ankle surgery (endoscopic os trigonum excision + FHL release and tenosynovectomy + tendon debridement if needed) performed NOW, (2) LEFT ankle managed conservatively for now (injections if needed), reassess after RIGHT recovery - may operate in off-season if needed, (3) Dedicated post-op rehabilitation with physiotherapist experienced in dancer return-to-dance protocols, (4) Realistic timeline - 6-8 months to return to professional principal dancer level, likely MISS Swan Lake performance (discuss with company about alternative roles or delaying surgery), (5) Close follow-up at 6 weeks, 12 weeks, 6 months, and 1 year to ensure optimal recovery and early detection of any complications. This is complex shared decision-making requiring detailed discussion of her career goals, risk tolerance, and timing priorities.