Episode Overview

Main Theme:
This episode is the second part of the AOFAS Orthopod-Cast "CMT MasterClass," where Drs. Pam Luke and Joe Park interview Dr. Glenn Pfeffer about the surgical management of Charcot-Marie-Tooth (CMT) disease and specifically the CMT Cavo Varus foot. Dr. Pfeffer shares expert insights on pain management, surgical techniques, post-operative protocols, and evolving consensus on best practices, drawing from deep personal experience and recent literature.

Key Discussion Points and Insights

1. Pain Management and Post-Operative Protocols

Timestamps: 00:38–03:50

• Unique Pain Considerations in CMT Patients:

  • CMT patients have "very reactive nerves," leading to "much more pain than normal patients." (Glenn Pfeffer, 01:22)
  • There is some reluctance among anesthesia groups to use popliteal blocks due to neuropathy risks.

• Use of Nerve Catheters:

  • Dr. Pfeffer strongly advocates continuous nerve catheters for postoperative pain control, referencing a published paper by Tanya Ang.
  • "It's a game changer...I actually would have stop doing CMT surgery without nerve catheters." (Glenn Pfeffer, 02:43)
  • Emphasizes they avoid inpatient stays by ensuring adequate outpatient pain control.

• Personal Insight:

  • Dr. Pfeffer relates his personal experience with foot surgery and pain: "I'm a sensitive guy and I've had three foot surgeries...so I think that's certainly what bonds me to these patients." (Glenn Pfeffer, 03:22)

2. Surgical Approach: Osteotomies and Incision Planning

Timestamps: 03:50–10:03

• Challenges of Deformity:

  • Calcaneal deformity in CMT is "multiplanar," often with a "C-shaped calcaneus," and requires individualized correction (04:36).

• Incision Preferences and Soft Tissue Management:

  • Prefers a single long lateral incision for exposure, rarely facing wound healing problems unless in revision surgery.
  • "These are not smokers, they're healthy people. I've never had a problem with that incision." (Glenn Pfeffer, 05:09)

• Calcaneal Osteotomy:

  • Lateralizing calcaneal osteotomies rarely work due to the severe curvature: "The Dwyer...is probably the best one to do. But even that's not enough."
  • Often combines a Dwyer osteotomy with shift and rotation of the calcaneus, requiring division of the plantar fascia for adequate movement.
  • “You can't decide what to do with the forefoot until you've done the heel correction. This is all...a giant audible.” (Glenn Pfeffer, 08:05)

• Forefoot Correction:

  • Uses closing wedge osteotomies in adults and often an opening wedge cuneiform osteotomy in children, with fresh frozen allograft, to correct first ray alignment.
  • “It's a beautiful operation...It just sticks in there. You don't have to use fixation.” (Glenn Pfeffer, 09:30)

3. Tendon Transfers & Peroneal Tendon Techniques

Timestamps: 10:03–15:47

• Peroneal Tendon Management:

  • Advocates for a 'pullover Taft weave' technique for transferring peroneus longus to brevis, discouraging side-to-side weaves.
  • “The pullover Taft weave with three throws may take an extra five minutes, but you can really tighten it up.” (Glenn Pfeffer, 10:56)

• Managing Scar Tissue and Tunnel Bulk:

  • Takes out the os peroneum when necessary and thins the peroneus longus for better results.

• FHL Transfers:

  • Uses FHL when peroneals are badly scarred or insufficient.

• Tensioning:

  • Tensions peroneal transfer in as much eversion as possible but notes CMT patients tend to stretch the repairs over time.
  • “No matter how tight I do it in CMT, doesn't ever seem to be quite tight enough.” (Glenn Pfeffer, 13:38)

4. Complications and Technical Pearls

Timestamps: 15:47–17:45

• Avoiding Peroneal Tendon Subluxation:

  • Important: Do not dissect above the tip of the fibula; if done, repair the peroneal sheath.
  • Unique revision anecdote: Placed tendon under the calcaneofibular ligament after repeated failure.
  • "That's like rare as hen's teeth." (Glenn Pfeffer, 16:43)

• Tendon Repair Power and Tensioning:

  • For allografts in athletes, keeps foot neutral and applies about 75% tension—enough to maintain function without overstraining.

5. Updates Since the Consensus Statement

Timestamps: 17:45–23:35

• Releasing All Necessary Soft Tissues:

  • “Just release all your soft tissues. Everything that's going to be released, release.” (Glenn Pfeffer, 18:16)
  • Particularly emphasizes releasing plantar fascia and addressing the Achilles tendon—even in cases where its role is debated.

• Approach is Not 'Cookbook':

  • CMT1A tends to be more stereotyped (cookbook); axonal variants (CMT2, non-1A) present differently and require more nuanced strategies.
  • Importance of carefully assessing peroneus longus strength—uncertain measurement reproducibility.

• Achilles Tendon:

  • Advocates for triple hemisection/lengthening and points out over-lengthening is unlikely: "You can't really over lengthen it. Not really, as the talus doesn't go up enough..." (Glenn Pfeffer, 20:36)

• Toe Extensor Transfers:

  • Sometimes transfers toe extensors, especially in children, where posterior tibial tendon transfer is rare.

• Reading and Learning:

  • Encourages deep review of the (relatively limited) clinical literature: "You can really get a handle on it if you want to." (Glenn Pfeffer, 24:57)

6. The Role and Timing of Surgery & CMT Populations

Timestamps: 25:39–27:06

• Timing of Surgery:

  • “When somebody can't walk in a brace comfortably, that's the time to do the surgery. And I don't care if they're 7 years old or...74.” (Glenn Pfeffer, 26:21)
  • Emphasizes not delaying for age; timing should be based on functional need.

• Geographical CMT Populations:

  • Notes interesting genealogical clusters (e.g., Harrisonburg, VA) due to stable gene pools, affecting local prevalence.

• Invitations and Collaboration:

  • Open to sharing expertise in person and collaborating on patient care or education.

Notable Quotes

On Pain Management and Outpatient Care

• "I actually would have stop doing CMT surgery without nerve catheters. It would have been just too...inhumane."
  — Glenn Pfeffer (02:43)

On the Art of Surgical Decision-Making

• "This CMT surgery is a giant audible. You really plan it out beforehand, but...you don't have any idea what's going to happen until the soft tissues are released. So some brains hate this. My brain loves it, trying to figure this out as you go."
  — Glenn Pfeffer (08:03)

On Peroneal Transfers and Tensioning

• "The pullover Taft weave with three throws may take an extra five minutes, but you can really tighten it up...you can't tighten as well [with] a side to side transfer."
  — Glenn Pfeffer (10:56)
• "No matter how tight I do it in CMT, it doesn't ever seem to be quite tight enough."
  — Glenn Pfeffer (13:38)

On Literature and Consensus

• "Everything about CMT is out there. I don't think there's anything new under the sun. You just have to read it all and put it together."
  — Glenn Pfeffer (24:57)

On Indications for Surgery

• "Don't let a crooked foot in a brace...Sometimes you meet young people who just don't want to wear braces. And if they've got the muscle strength available, that's reasonable..."
  — Glenn Pfeffer (26:23)

Important Segment Timestamps

| Timestamp | Content | |-----------|---------| | 00:53 | Pain management regimen; nerve blocks and use of catheters | | 04:06 | Preferred incisions and approach to calcaneal osteotomy | | 09:00 | Forefoot correction: closing wedge in adults, opening wedge in kids | | 10:56 | Tendon transfer techniques: Taft weave vs. side-to-side | | 12:37 | Tensioning transferred tendons | | 17:45 | Consensus statement: what's changed in five years | | 24:09 | Plantar fascia release: techniques and rationale | | 26:12 | Timing for surgery based on functional need |

Episode Tone & Takeaways

The tone throughout the episode is pragmatic, deeply instructive, and supportive, with Dr. Pfeffer emphasizing the necessity of tailoring techniques to individual patients, the importance of comprehensive tissue release, and the value of reading widely and thinking critically. There is a collegial sense among the hosts, with practical troubleshooting and the sharing of institutional and personal experiences.

This episode is invaluable for surgeons seeking advanced, candid insight into CMT foot management—not only into the “how” but the “why,” and the limitations of textbook algorithms in a complex, genetically variable disorder.