All-Natural Modified Lapidus for Severe Hallux Valgus Correction

Author: Garret Strand, DPM, Shasta Orthopaedics and Sports Medicine, CA.

INTRODUCTION

Hallux Abducto Valgus (HAV) (also referred to as Hallux Valgus (HV) or Bunion) is one of the most common deformities in the foot and ankle field. This pathological condition involves malpositioning of the first metatarsophalangeal (MTP) joint, caused by both a medial deviation of the first metatarsal bone and a lateral deviation and pronation of the great toe. While HAV prevalence reaches 23% in adults 18-65 years of age, it peaks to 35.7% in those older than 65 years. Females have considerably higher prevalence for the deformity¹. Additional predisposing factors are family history, metatarsus adductus, first ray hypermobility, pes planus, equinus contracture, ligamentous laxity, and length of the first metatarsal¹. HAV symptoms include altered joint mechanics, dysfunction, and progressive pain often at the medial eminence of the first MTP joint. This deformity can vary from mild to severe. More than 100 different operative techniques have been described for the correction of HAV, however no single procedure is universally successful in all patients with severe HAV and even technically well-performed procedures may fail^2,3. While mild to moderate HAV can usually be corrected with a distal osteotomy of the first metatarsal, severe HAV deformities with subluxation of the hallux joint, hypermobility of the first tarsometatarsal (TMT) joint, or generalized laxity as well as recurrent HAV following surgical corrections, are the main indications in the literature for a corrective fusion of the first TMT joint, the so-called modified Lapidus. High union rates and high-level of patient satisfaction encourage correction using Lapidus procedure, in particular for severe HAV conditions.

CASE PRESENTATION

63-year-old, healthy female, non-smoker, with daily routine of moderate physical demands. The patient complained of left foot pain on ambulation, and difficulty with shoe gear. On examination, severe HAV clinical appearance with large deviation of the hallux laterally and hypermobility at the first TMT. The patient requested non-metal surgical fixation.

Pre-operative Planning

Weight bearing radiographs reveal severe HAV with increase in tibial sesamoid position and 1^st Inter Metatarsal (IM) angle.

Screenshot 2024 09 05 At 18.50.44 Ossio – Naturally Transformative Bone Healing — **Figure 1**: Pre-operative X-rays; AP [A], AP weightbearing projection [B] and Lateral [C].

Surgical Procedure

First TMT joint arthrodesis, Calcaneal autograft harvest.
The following OSSIOfiber^® fixation implants were used:

OSSIOfiber^®Compression Screw 3.5x28mm x 1 unit
OSSIOfiber^® Compression Screw 3.5x30mm x 1 unit
OSSIOfiber^® Compression Screw 3.5x32mm x 1 unit

Surgical Technique Steps

Dissection / Access :
Dorsal medial 1^st TMT incision, lateral release was performed with mini open incision, 1^st TMT was hand prepped, and autograft was packed within joint and temporarily fixated with 0.062″ k-wires. A manual reduction was performed.
Fixation Site Preparation :
Hand preparation, fenestrated until bleeding bone was present.
Implant Insertion :
Three 3.5mm OSSIOfiber^® headless Compression Screws were used, two crossing the TMT for compression, third one from M1 to M2 base to hold transverse correction due to large pre op deformity angle.
Closure
3-0 vicryl for deep and superficial closure, 3-0 nylon for skin.

Screenshot 2024 09 05 At 19.06.47 Ossio – Naturally Transformative Bone Healing — **Figure 2**: Intra-operative Fluoroscopy following fixation with OSSIOfiber^® devices; AP [A] and Lateral [B]

Post-Operative Protocol

Non-weight bearing: 6 weeks
Transition to partial weight bearing: CAM boot for 6 weeks with physical therapy.
Full weight bearing: In supportive tennis shoes after 12 weeks.

Patient Follow-up

The surgical site completely healed by the time the patient came in for the 2 weeks check-up, and sutures were removed. Swelling was minimal over the 1^st TMT joint, with minimal discomfort over the joint through initial healing phase. Physical therapy started at 6 weeks post op. 1^st MTP joint range of motion improved gradually with passive and active exercises. Sequent radiographs showed well maintained bone reduction and increased signs of fusion from visit to visit.

Screenshot 2024 09 05 At 19.09.37 Ossio – Naturally Transformative Bone Healing — **Figure 3:** 6 months Post-operative X-rays: AP [A], AP, illustrated implants demonstrate 3-corner hardware trajectories [B] Oblique [C] and Lateral [D].

Screenshot 2024 09 05 At 19.10.17 Ossio – Naturally Transformative Bone Healing — **Figure 4:** Side-by-side comparison of pre-[A] Vs post- [B] operative X-rays.

Screenshot 2024 09 05 At 19.11.01 Ossio – Naturally Transformative Bone Healing — **Figure 5:** Images of patient’s operated foot 6 months following surgery [A&B].

Summary:

First TMT fusions are a reliable and reproducible way to correct severe HAV deformities. Patients are more aware and involved in their medical care than ever before and the trend is moving away from using permanent hardware such as metal/plastics within the body, to a more natural fixation. Bio-integrative implants offer an excellent alternative way of fixating challenging deformities such as the one presented here, providing the required mechanical fixation strength while avoiding the need to deal with retained hardware later in life.

References

1. Ray, J. J. et al. Hallux Valgus. Foot Ankle Orthop. 4, 1–12 (2019).

2. Pinney, S., Song, K. R. & Chou, L. B. Surgical treatment of severe hallux valgus: the state of practice among academic foot and ankle surgeons. Foot ankle Int. 27, 1024–1029 (2006).

3. Fraissler, L., Konrads, C., Hoberg, M., Rudert, M. & Walcher, M. Treatment of hallux valgus deformity. EFORT Open Rev. 1, 295–302 (2016).

INTRODUCTION