Transverse Z-Osteotomy: Is It A Viable Adjunctive Option For Hallux Limitus?
There have been many surgical treatment modalities described in the podiatric and orthopedic literature for the correction of hallux limitus.1-5 Since the Regnauld procedure was introduced in 1968, surgeons have used it in the treatment of a pathologically long proximal phalanx and hallux limitus.6 However, since its development, this procedure has been characterized as a technically challenging procedure for the treatment of hallux limitus with or without moderate degenerative arthritis.7-10
In 1995, Kissel, et. al., and Hodor, et. al., introduced the sagittal Z-osteotomy, and Gusman, et. al., introduced the Newell decompression osteotomy for the proximal phalanx of the hallux. These authors described the two procedures as alternatives to the Regnauld procedure and included a compilation of indications, advantages and disadvantages.11-13
We believe the transverse Z-osteotomy offers another suitable osteotomy for the proximal phalanx when it comes to joint preservation and correction of hallux limitus in conjunction with a first metatarsal osteotomy.
In previous studies, Kessel and Youngswick emphasized the importance for a first metatarsal decompression osteotomy in treating hallux limitus.14,15 The articles by Hodor and Gusman have also reported using a first metatarsal osteotomy in conjunction with a hallux osteotomy.11,13
A complete discussion of hallux limitus pathomechanics is beyond the scope of this article and has been published extensively in the past. However, it is important to note that the lack of appreciation to these pathomechanics will lead to surgical failure. Durrant and Siepert offered an elegant guide to the understanding of the mechanical criteria and soft tissue involvement around the first metatarsophalangeal joint (MTPJ) in hallux limitus.16
While this is by no means an exhaustive list, here are some proposed indications, advantages and disadvantages for the transverse Z-osteotomy.
Indications for the transverse Z-osteotomy include: mild to moderate degenerative joint disease of the first metatarsophalangeal joint; a painful first metatarsophalangeal joint; excessive retrograde pressure of the hallux on the head of the first metatarsal; a pathologically long proximal phalanx; cosmetic improvement of an excessively long hallux; and a reduction in range of motion at the first metatarsophalangeal joint.
Assessing The Pros And Cons Of The Procedure
The advantages of the procedure include:
• complete anatomical protection for the attachments of the adductor hallucis, abductor hallucis, flexor hallucis brevis, capsule and ligamentous attachments;
• correction of a pathologically long proximal phalanx of the hallux;
• correction of a pathologic hallux abductus interphalangeus or hallux equinus, sparing the first metatarsophalangeal joint;
• excellent stability along the osteotomy site;
• increased range of motion at the first metatarsophalangeal joint by relaxing the muscular, capsular and ligamentous structures after shortening of the proximal phalanx;
• no contraindication with mild osteopenia;
• an immediate return to weightbearing assuming no contraindicating proximal procedure;
• a procedure that is technically less difficult than the Regnauld procedure;
• a lack of complications associated with an autogenous bone graft;
• the ability to use a Kirschner wire osteotomy guide to ensure accurate and reproducible osteotomies;
• a reduced risk of avascular necrosis; and
• an excellent extraarticular, joint sparing osteotomy alternative for the young patient.
Disadvantages include the requirement of internal fixation and all complications inherent with any osteotomy.