Reverse Austin Osteotomy for Correction of
Hallux Varus
Hallux varus has been described by many investigators. For a thorough review of the literature, the work
of Greenfogel et al. is recommended (1). This manuscript, however, will attempt to briefly highlight the
history and treatment of hallux varus.
Silver (2) and McBride (3) first described hallux varus as an iatrogenic complication of bunion surgery. Two basic types of hallux varus have been described: acquired and congenital. The etiology of acquired hallux varus has been mostly attributed to an overzealous McBride bunionectomy (3, 4). Janis and Donick (5), in reviewing 1100 McBride bunionectomies, postulated that a long first metatarsal, a round metatarsal head, and an intermetatarsal angle below 8 degrees contributed to hallux varus (also referred to as hallux adductus) and was slightly greater than 1% after McBride bunion corrections.
Edmonson attributed hallux varus to intraoperative capsular overcorrection, resection of too much bone medially, and dominance of the abductor hallucis muscle (6). Hansen (7), Hawkins (8), and Miller (9) noted the association between hammer toe deformity of the hallux and hallux varus. They also noted the correlation between resection of the lateral sesamoid bone with interruption of the flexor hallucis brevis muscle apparatus to hallux varus.
Hawkins (8) postulated that as the extensor mechanism of the joint becomes tighter, plantar flexion becomes more limited and the incidence of hallux varus increases. He was the first to associate extensor mechanism disorders with hallux varus. Seeburger and Bradlee have attributed securing the extensor hallucis longus tendon too medially during wound closure as a contributory factor in hallux varus formation (10).
Congenital hallux varus is a rare entity. It is usually associated with supernumerary digits and/or polydactyly (11). Thompson (12) describes two types of congenital hallux varus: primary and secondary. Primary hallux varus is present when no other contributory factor can be found, i.e., an isolated finding. Secondary hallux varus is found in combination with congenital equino varus or clubfoot deformities. The abductor hallucis muscle has been described as the primary deforming force in congenital hallux varus; however, it has been proved that in over 80% of cases studied the abductor muscle acted as a stabilizing force rather than as a functional deforming force (1)
The treatment of hallux varus consists of three categories: 1 ) soft tissue procedures, 2) osseous procedures, and 3) joint destructive procedures. Soft tissue procedures include medial capsulotomy; lateral capsulorraphy; tendon lengthening, transfers, and releases. Hawkins (8) described the abductor hallucis transfer as transposition of the abductor tendon to the phalangeal base. Osseous procedures have included tibial sesamoid excision reverse Reverdin osteotomy, and reverse Akin osteotomy for realignment and repositioning of the hallux. The third and probably least difficult technically are the joint destructive procedures mainly Keller arthroplasty and total joint replacement.
The following study describes an unusual case of hallux varus. These investigators feel this case to be worthy of mention due to its atypical presentation and treatment.
Case Report
A 54-year-old white woman presented to the Baptist Medical Center of Brooklyn, N.Y., with the chief complaint of a painful right great toe. The patient related no history of previous trauma or surgery to the foot. She complained that the toe was "sticking straight up" and painful when wearing shoes. The condition was present for several years and increasing in severity and symptomatology during the past 2 years.
Upon examination of the foot, severe bow stringing of the extensor hallucis longus tendon was noted as well as an equally severe hallux varus deformity. The patient demonstrated a flexible anterior global cavus foot type bilateral as well as a marked ligamentous laxity. The left foot was asymptomatic without osseous or soft tissue deformity. The area of chief complaint was the distal right hallux where irritation from shoe gear had caused localized erythema and tenderness to the digit and toenail. The range of motion (passive) of the right hallux exhibited normal dorsiflexion and plantarflexion. There was neither crepitus nor pain noted in the corrected and uncorrected halilix nasition The extensus did not involve the interphalangeal joint and there was no hammer toe deformity of the hallux. The patient was preliminarily scheduled for an extensor hallucis tendon lengthening with soft tissue release and realignment of the first metatarsophalangeal joint capsule.
The systemic history was positive for asthma and cholecystitis, both medically controlled. She denied prior surgery as well as previous trauma or allergies. Laboratory findings urinalysis, and electrocardiogram were all normal. Chest radiography was unremarkable. Weight-bearing x-rays of the left foot were also normal. Weight-bearing x-rays of the right foot are described in Figures 1 and 2.
Procedure
The patient was brought to the operating room and prepared in the usual aseptic fashion. Under satisfactory local anesthesia with intravenous sedation, a 4-cm dorsomedial incision was placed overlying the first metatarsophalangeal joint of the right foot. The incision was deepened using sharp dissection to expose the extensor hallucis tendon apparatus and medial and lateral joint capsule. Attention was then directed to the extensor hallucis longus tendon and sheath, which was then tagged at its most proximal point using 2-0 absorbable suture. A "Z" lengthening was then performed, completely separating the segments of tendon. The hallux remained in its severely adducted position. Attention was redirected to the medial capsule of the first metatarsophalangeal joint where, using blunt dissection, the tendon of the abductor hallucis muscle was identified, isolated, and not found to be abnormally taut or malpositioned. This tendon was then transected and the position of the hallux still remained unimproved.
A medial capsulotomy was performed. The cartilage of the first metatarsophalangeal joint was adapted from medial to lateral and was of normal structure and function in all positions. There was still no improvement in the hallux position noted. Lateral capsulorrhaphy and release of the intermetatarsal ligament did not improve the adducted hallux position.
It was now apparent that the patient's decreased intermetatarsal angle was a strong contributing factor (Fig. 3). Hence, a reverse Austin (13) osteotomy was performed to effectively increase the intermetatarsal angle. An Austin-type osteotomy was then performed; however, the capital fragment was transposed medially until the hallux resumed a normal alignment. The range of motion of the hallux in its new position was normal. A 0.045-inch Kirschner wire was introduced from distal-medial to lateral-proximal. The capital fragment was secure.
The extensor hallucis longus tendon was repaired in its elongated position using 3-0 Tevdek4 suture. Subcutaneous closure was performed with 4-0 absorbable suture. Skin closure was then achieved by using 5-0 nylon simple interrupted sutures. The surgical site was dressed with sterile gauze and gauze wrap, followed by an elastic bandage.
The patient tolerated the procedure well and left the operating room with vital signs stable and all digits perfused with normal capillary filling.
Postoperative Results
The immediate postoperative appearance of the foot is shown in Figure 4. Adequate realignment of the hallux was achieved. X-ray tracings were made and the angles redrawn (Fig. 5). Postoperative x-ray findings include reduction of the metatarsal-cuneiform angle (Fig. 6). This angle is of particular interest in supporting the procedure performed and in attempting to understand the etiology of this condition.
The abnormal first metatarsal cuneiform angle was caused by three factors: a reverse buckling effect of the hallux upon the first metatarsal, an adapted or congenital tightness of the intermetatarsal ligament and/or an anomalous attachment of the adductor hallucis muscle, and the contribution of a tight extensor tendon apparatus.
The patient's postoperative course was unremarkable with minimal pain and edema. Sutures were removed after 10 days. She presented 1 week later with irritation and erythema at the pin site as well as partial inward migration of the Kirschner wire itself, which was removed in approximately 2 ½ weeks. Antibiotics were not prescribed due to the benign presentation of the pin site and the patient's admission to excessive ambulation. The foot was redressed and placed in a non-weight-bearing plaster posterior splint.
After 3 months the patient was asymptomatic and able to wear normal shoe gear (Figs. 7 and 8). She was again seen 5 months later, still asymptomatic and pleased with the appearance and function of her right foot (Fig. 9). The migration of the hallux, although unnoticed by thc patient, was probably due to early removal of the Kirschner wire. The patient was again seen at our facility for follow-up after 8 months, and she remained asymptomatic with normal hallux position.
Discussion
This case is of particular interest because there is no history of previous surgical intervention or trauma and the etiology of this form of hallux varus has not been adequately addressed in the podiatric or orthopedic literature. These investigators propose the following theory as a possible cause of this type of hallux varus.
The patient was born with a low angle between the first and second metatarsals of the right foot, a roundshaped first metatarsal head, and a considerable amount of ligamentous laxity. Her foot, being a flexible type anterior cavus, contributed to extensor substitution and digital contractions during gait. As the extensor hallucis tendon began to tighten, the hallux sought the position most easily adapted, in this case, varus. Over a period of years, the reverse buckling effect may have caused tightening and contraction of the lateral capsular structures, resulting in a further decrease in the intermetatarsal angle and an increase in the angle at the first metatarsal cuneiform joint. The intermetatarsal angle of the left foot was measured to be 8 degrees. The first metatarsal cuneiform angle may, therefore, serve as an indicator to the surgeon as to the necessity of lateral capsular ligamentous release and/or intermetatarsal correction in similar cases.
Summary
An unusual case of hallux varus and extensus has been presented. The reverse Austin bunionectomy was used after several attempts to release soft tissue structures failed. The procedure was found to be simple and effective for this particular patient's problem. Other alternatives to this case included tibias sesamoid resection, Keller bunionectomy, adductory base wedge, or total joint implant; however, the need to increase the intennetatarsal angle and preserve the integrity of the joint appeared to be of utmost importance. The postoperative result did not create a bunion deformity, but restored the intermetatarsal angle and hallux position to a more functional attitude. The result was acceptable to the patient and the surgical team.
Acknowledgment
Special thanks to Jane Walter, D.P.M., for her photography.
References
A case of hallux varus and extensus of unusual etiology and treatment is presented. Special emphasis is
directed toward the angle formed between the first metatarsal base and medial cuneiform, which these
investigators believe has not been previously described. The procedure performed is a reverse Austin
bemionectomy with a step-by-step outline of soft tissue procedures attempted before osteotomy. The
cartilage at the first metatarsal head was medially adapted and of normal structure and function
preoperatively; therefore the decision was made to perform a joint preservation procedure.
| Mary Ann Bilotti, D.P.M.1 Russell Capnoli, D.P.M.2 Jack Testa, D.P.M.2 |
Russell Cournoyer, Jr., D.P.M.2 Frank J. Esposito, D.P.M., F.A.C.F.A.S.3 |
Silver (2) and McBride (3) first described hallux varus as an iatrogenic complication of bunion surgery. Two basic types of hallux varus have been described: acquired and congenital. The etiology of acquired hallux varus has been mostly attributed to an overzealous McBride bunionectomy (3, 4). Janis and Donick (5), in reviewing 1100 McBride bunionectomies, postulated that a long first metatarsal, a round metatarsal head, and an intermetatarsal angle below 8 degrees contributed to hallux varus (also referred to as hallux adductus) and was slightly greater than 1% after McBride bunion corrections.
Edmonson attributed hallux varus to intraoperative capsular overcorrection, resection of too much bone medially, and dominance of the abductor hallucis muscle (6). Hansen (7), Hawkins (8), and Miller (9) noted the association between hammer toe deformity of the hallux and hallux varus. They also noted the correlation between resection of the lateral sesamoid bone with interruption of the flexor hallucis brevis muscle apparatus to hallux varus.
Hawkins (8) postulated that as the extensor mechanism of the joint becomes tighter, plantar flexion becomes more limited and the incidence of hallux varus increases. He was the first to associate extensor mechanism disorders with hallux varus. Seeburger and Bradlee have attributed securing the extensor hallucis longus tendon too medially during wound closure as a contributory factor in hallux varus formation (10).
Congenital hallux varus is a rare entity. It is usually associated with supernumerary digits and/or polydactyly (11). Thompson (12) describes two types of congenital hallux varus: primary and secondary. Primary hallux varus is present when no other contributory factor can be found, i.e., an isolated finding. Secondary hallux varus is found in combination with congenital equino varus or clubfoot deformities. The abductor hallucis muscle has been described as the primary deforming force in congenital hallux varus; however, it has been proved that in over 80% of cases studied the abductor muscle acted as a stabilizing force rather than as a functional deforming force (1)
The treatment of hallux varus consists of three categories: 1 ) soft tissue procedures, 2) osseous procedures, and 3) joint destructive procedures. Soft tissue procedures include medial capsulotomy; lateral capsulorraphy; tendon lengthening, transfers, and releases. Hawkins (8) described the abductor hallucis transfer as transposition of the abductor tendon to the phalangeal base. Osseous procedures have included tibial sesamoid excision reverse Reverdin osteotomy, and reverse Akin osteotomy for realignment and repositioning of the hallux. The third and probably least difficult technically are the joint destructive procedures mainly Keller arthroplasty and total joint replacement.
The following study describes an unusual case of hallux varus. These investigators feel this case to be worthy of mention due to its atypical presentation and treatment.
Case Report
A 54-year-old white woman presented to the Baptist Medical Center of Brooklyn, N.Y., with the chief complaint of a painful right great toe. The patient related no history of previous trauma or surgery to the foot. She complained that the toe was "sticking straight up" and painful when wearing shoes. The condition was present for several years and increasing in severity and symptomatology during the past 2 years.
Upon examination of the foot, severe bow stringing of the extensor hallucis longus tendon was noted as well as an equally severe hallux varus deformity. The patient demonstrated a flexible anterior global cavus foot type bilateral as well as a marked ligamentous laxity. The left foot was asymptomatic without osseous or soft tissue deformity. The area of chief complaint was the distal right hallux where irritation from shoe gear had caused localized erythema and tenderness to the digit and toenail. The range of motion (passive) of the right hallux exhibited normal dorsiflexion and plantarflexion. There was neither crepitus nor pain noted in the corrected and uncorrected halilix nasition The extensus did not involve the interphalangeal joint and there was no hammer toe deformity of the hallux. The patient was preliminarily scheduled for an extensor hallucis tendon lengthening with soft tissue release and realignment of the first metatarsophalangeal joint capsule.
The systemic history was positive for asthma and cholecystitis, both medically controlled. She denied prior surgery as well as previous trauma or allergies. Laboratory findings urinalysis, and electrocardiogram were all normal. Chest radiography was unremarkable. Weight-bearing x-rays of the left foot were also normal. Weight-bearing x-rays of the right foot are described in Figures 1 and 2.
Procedure
The patient was brought to the operating room and prepared in the usual aseptic fashion. Under satisfactory local anesthesia with intravenous sedation, a 4-cm dorsomedial incision was placed overlying the first metatarsophalangeal joint of the right foot. The incision was deepened using sharp dissection to expose the extensor hallucis tendon apparatus and medial and lateral joint capsule. Attention was then directed to the extensor hallucis longus tendon and sheath, which was then tagged at its most proximal point using 2-0 absorbable suture. A "Z" lengthening was then performed, completely separating the segments of tendon. The hallux remained in its severely adducted position. Attention was redirected to the medial capsule of the first metatarsophalangeal joint where, using blunt dissection, the tendon of the abductor hallucis muscle was identified, isolated, and not found to be abnormally taut or malpositioned. This tendon was then transected and the position of the hallux still remained unimproved.
A medial capsulotomy was performed. The cartilage of the first metatarsophalangeal joint was adapted from medial to lateral and was of normal structure and function in all positions. There was still no improvement in the hallux position noted. Lateral capsulorrhaphy and release of the intermetatarsal ligament did not improve the adducted hallux position.
It was now apparent that the patient's decreased intermetatarsal angle was a strong contributing factor (Fig. 3). Hence, a reverse Austin (13) osteotomy was performed to effectively increase the intermetatarsal angle. An Austin-type osteotomy was then performed; however, the capital fragment was transposed medially until the hallux resumed a normal alignment. The range of motion of the hallux in its new position was normal. A 0.045-inch Kirschner wire was introduced from distal-medial to lateral-proximal. The capital fragment was secure.
The extensor hallucis longus tendon was repaired in its elongated position using 3-0 Tevdek4 suture. Subcutaneous closure was performed with 4-0 absorbable suture. Skin closure was then achieved by using 5-0 nylon simple interrupted sutures. The surgical site was dressed with sterile gauze and gauze wrap, followed by an elastic bandage.
The patient tolerated the procedure well and left the operating room with vital signs stable and all digits perfused with normal capillary filling.
Postoperative Results
The immediate postoperative appearance of the foot is shown in Figure 4. Adequate realignment of the hallux was achieved. X-ray tracings were made and the angles redrawn (Fig. 5). Postoperative x-ray findings include reduction of the metatarsal-cuneiform angle (Fig. 6). This angle is of particular interest in supporting the procedure performed and in attempting to understand the etiology of this condition.
The abnormal first metatarsal cuneiform angle was caused by three factors: a reverse buckling effect of the hallux upon the first metatarsal, an adapted or congenital tightness of the intermetatarsal ligament and/or an anomalous attachment of the adductor hallucis muscle, and the contribution of a tight extensor tendon apparatus.
The patient's postoperative course was unremarkable with minimal pain and edema. Sutures were removed after 10 days. She presented 1 week later with irritation and erythema at the pin site as well as partial inward migration of the Kirschner wire itself, which was removed in approximately 2 ½ weeks. Antibiotics were not prescribed due to the benign presentation of the pin site and the patient's admission to excessive ambulation. The foot was redressed and placed in a non-weight-bearing plaster posterior splint.
After 3 months the patient was asymptomatic and able to wear normal shoe gear (Figs. 7 and 8). She was again seen 5 months later, still asymptomatic and pleased with the appearance and function of her right foot (Fig. 9). The migration of the hallux, although unnoticed by thc patient, was probably due to early removal of the Kirschner wire. The patient was again seen at our facility for follow-up after 8 months, and she remained asymptomatic with normal hallux position.
Discussion
This case is of particular interest because there is no history of previous surgical intervention or trauma and the etiology of this form of hallux varus has not been adequately addressed in the podiatric or orthopedic literature. These investigators propose the following theory as a possible cause of this type of hallux varus.
The patient was born with a low angle between the first and second metatarsals of the right foot, a roundshaped first metatarsal head, and a considerable amount of ligamentous laxity. Her foot, being a flexible type anterior cavus, contributed to extensor substitution and digital contractions during gait. As the extensor hallucis tendon began to tighten, the hallux sought the position most easily adapted, in this case, varus. Over a period of years, the reverse buckling effect may have caused tightening and contraction of the lateral capsular structures, resulting in a further decrease in the intermetatarsal angle and an increase in the angle at the first metatarsal cuneiform joint. The intermetatarsal angle of the left foot was measured to be 8 degrees. The first metatarsal cuneiform angle may, therefore, serve as an indicator to the surgeon as to the necessity of lateral capsular ligamentous release and/or intermetatarsal correction in similar cases.
Summary
An unusual case of hallux varus and extensus has been presented. The reverse Austin bunionectomy was used after several attempts to release soft tissue structures failed. The procedure was found to be simple and effective for this particular patient's problem. Other alternatives to this case included tibias sesamoid resection, Keller bunionectomy, adductory base wedge, or total joint implant; however, the need to increase the intennetatarsal angle and preserve the integrity of the joint appeared to be of utmost importance. The postoperative result did not create a bunion deformity, but restored the intermetatarsal angle and hallux position to a more functional attitude. The result was acceptable to the patient and the surgical team.
Acknowledgment
Special thanks to Jane Walter, D.P.M., for her photography.
- From the Department of Podiatry, Baptist Medical Center, Brooklyn, New York.
- 1 Address correspondence to: 300 N. Central Avenue, Valley Stream, New York 11580.
- 2 Submitted during second-year residency.
- 3 Chief, Department of Podiatry; Director, residency training program; Diplomate, American Board
- 1 Address correspondence to: 300 N. Central Avenue, Valley Stream, New York 11580.
- of Podiatric Surgery.
0449/2544/87/0262 0051$02.00/0
Copyright © 1987 by The American College of Foot Surgeons
- 4 Ethicon, Inc., Sommerville, N.J.
References
- 1. Greenfogel, S. I., Glubo, S., Werner, J., Sherman, M., and Lenet,
M. Hallux varus: surgical correction
- and review of the literature.
J. Foot Surg. 23:46-50, 1984.
- 2. Silver, D. The operative treatment of hallux valgus. J. Bone Joint
Surg. 5:225-232, 1923.
- 3. McBride, E. D. The conservative operation for "bunions"-end results and refinements of technique.
- J.A.M.A. 105:1164-1168,
1935.
- 4. Feinstein, M. H., and Brown, H. N. Hallux adductus as a surgical complication. J. Foot Surg.
- 19:207-211, l980.
- 5. Janis, L. F., and Donick, I. I. The etiology of hallux varus: a review. l. Am. Podiatry Assoc.
- 65:233-237, 1975.
- 6. Edmonson, A. S. Campbell's Operative Orthopedics, 5th ed. pp. 1808-1824, C. V. Mosby, St. Louis,
- 1971.
- 7. Hansen, C. E., Hallux valgus treated by the McBride operation follow-up. Acta Orthop. Scand.
- 45:778-792, 1974.
- 8. Hawkins, F. B. Acquired hallux varus; cause, prevention, and correction. Clin. Orthop. 76:169-176,
- 1971.
- 9. Miller, J. W. Acquired hallux varus: a preventable and correctable disorder. J. Bone Joint Surg.
- 57A:183-188, 1975.
- 10. Seeburger, R. H., and Bradlee, N. Surgically induced hallux varus. J. Am. Podiatry Assoc. 59:190,
- 1969.
- 11. Farmer, A. W., Congenital hallux varus. Am. J. Surg. 95:274-
278, 1958.
- 12. Thomson, S. A. Hallux varus and metatarsus varus-A five year study. Clin. Orthop. 16:109-118, 1960.
- 13. Gerbert, J. Textbook of Bunion Surgery, pp. 123-164, Futura Publishing, Mount Kisco, N.Y., 1981
- 12. Thomson, S. A. Hallux varus and metatarsus varus-A five year study. Clin. Orthop. 16:109-118, 1960.
