Retrospective analysis of the Ludloff osteotomy for correction of severe hallux valugs deformity

Foot and Ankle Surgery 2001

7: 1±8

Retrospective analysis of the Ludloff osteotomy for correction of severe hallux valgus deformity A. BASILE, A. BATTAGLIA AND A. CAMPI Ospedale S. Giacomo-Roma, Divisione di Ortopedia e Traumatologia, Rome, Italy

Summary

The purpose of this study was to evaluate retrospectively the outcomes of the Ludloff osteotomy for severe hallux valgus. Thirty cases in 23 patients, with an average clinical follow-up of 29.5 months, are reported. The hallux valgus angle improved on average 22°, from a preoperative average of 33.8° to 11.8° at follow-up. The intermetatarsal (IM)1±2 angle improved on average 12.8°, from 19.6° preoperatively to 7.7° at follow-up. The lateral plantar ®rst metatarsal angle did not change; union occurred at an average of 6 weeks. Tibial sesamoid position improved from a preoperative average position of 2.8 to an average position of 0.6. The AOFAS Rating Score improved from a preoperative average of 48.8/100 to an average of 90.1/100 at followup. There were four patients with complications, including three cases with delayed unions and one with super®cial wound infection. We found a signi®cantly favourable correlation in the amount of IM 1±2 angle, hallux valgus and tibial sesamoid position correction when compared with an increased postoperative foot score. This is an important ®nding because there is a direct correlation here between improved measurable radiographical ®ndings and an improved subjective evaluation. Furthermore, we found a trend for a longer follow-up period to be correlated with a better postoperative foot score. Based on our results and on the review of the literature, we conclude that Ludloff osteotomy provides reliable successful longterm results for the treatment of severe symptomatic hallux valgus and metatarsus primus adductus deformity.

Keywords: metatarsus primus adductus; hallux valgus; Ludloff osteotomy

Introduction Severe metatarsus primus adductus can be de®ned as an intermetatarsal (IM) 1±2 angle of ³ 16° in the rectus foot type, and of ³ 12° for an adductus foot type [1]. In other words, a signi®cant hallux valgus

Correspondence: A. Basile, Viale di Vigna Pia, 32, 00149 Rome, Italy (e-mail: [email protected]). Ó 2001 Blackwell Science Ltd

deformity may occur even if the IM 1±2 angle is measured as normal, due to signi®cant adduction of the metatarsal bones (adductus foot type) [1, 2]. Several procedures have been described to reduce the metatarsus primus adductus component of hallux abductovalgus [2]. Proximal osteotomies have become popular for the more severe deformities because they allow greater correction than the distal metatarsal osteotomies [2, 4]. Several procedures have been described to correct metatarsus primus 1

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adductus, including Opening Wedge, Closing Wedge, Crescentic and Chevron [2, 4]. In recent years mid-shaft osteotomies have gained popularity. Procedures in this category include the Scarf or Z-osteotomy [5, 6], the Offset-V osteotomy [7], the Mau [8, 9] and the Ludloff osteotomy [10±12]. The Ludloff osteotomy was ®rst described in 1918 [10] and is a through-and-through osteotomy in the transverse plane extending dorsal-proximal to plantar-distal when viewed in the sagittal plane. This osteotomy con®guration allows for intermetatarsal angle reduction, metatarsal lengthening and plantar displacement as well as shortening and dorsal displacement. This con®guration is not intrinsically stable, therefore ®xation is necessary. The purpose of this report is to review our experience with a series of patients treated consecutively with bunionectomy, distal soft tissue procedure, Ludloff osteotomy and when indicated, Phalangeal osteotomy. The aim of this study was to clarify whether this procedure afforded satisfactory correction of complex bunion deformities. Indications, advantages and/or disadvantages of this method over others are discussed. The report also addresses pitfalls of the surgery, procedurespeci®c complications, technical demands, patient acceptance and overall outcome.

Patients and methods Patients Between 1996 and 1999, 23 patients (20 women and three men) underwent 30 Ludloff osteotomies in conjunction with other procedures for severe metatarsus primus adductus. Patients who underwent corrective bunion surgery on both feet did not have the surgeries performed simultaneously, as we believe that in order to adequately protect the operated foot the patient must be able to bear weight on the contralateral extremity in the immediate postoperative period. Criteria for inclusion in the study group were: being between 20 and 65 years of age; a preoperative IM 1±2 angle of ³ 16° for the rectus foot type; no prior involvement of hallux by surgery; osteoarthritis or in¯ammatory arthritis; and a minimum follow-

up of 1 year. A retrospective review of the Ludloff osteotomy was conducted. Patients who had undergone the procedure were asked to return to the of®ce for the completion of a questionnaire, examination of the operative foot and follow-up radiographs. Measurements included IM 1±2 angle, hallux valgus (HV) angle, distal metatarsal articular angle (DMAA), tibial sesamoid position (TSP), ®rst metatarsophalangeal joint subluxation and metatarsal length. Preoperative and follow-up dorsoplantar and lateral weight bearing radiographs and oblique radiographs of the foot were obtained. Angles were measured by the metatarsal and phalangeal shaft bisection lines method from the standing dorsoplantar radiographs. Sesamoid subluxation was measured from the scale of 0±3 based on the relationship of the tibial sesamoid to the line drawn down to the midlongitudinal axis of the ®rst metatarsal shaft (bisection line). First metatarsophalangeal joint subluxation was measured in millimeters from the standing dorsoplantar radiographs. Healing was assessed with non-weight-bearing radiographs until union of the osteotomy occurred. This was evidenced by trabecular bone bridging and callus at the osteotomy site, after which weightbearing ®lms were obtained. Subjective results were recorded on the questionnaire that asked patients about overall satisfaction, cosmesis, toe mobility, footwear restriction, length of postoperative disability, and whether they would consider having the procedure again. Furthermore, the clinical rating system for foot and ankle function established by Kitaoka et al. [13] (American Orthopedic Foot and Ankle Society (AOFAS) Hallux Metatarsophalangeal-Interphalangeal Score) was used as a quanti®cation of the above clinical and subjective evaluations before and after surgery. The Student's t-test was used to compare the AOFAS Score before and after the operation. The linear regression analysis was used to determine whether a signi®cant correlation was present between variables. Differences in P-values of < 0.05 were considered statistically signi®cant.

Ó 2001 Blackwell Science Ltd, Foot and Ankle Surgery 2001, 7, 1±8

O S T EO TO M Y FO R M I LD H A L LU X V A L G U S

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Surgical technique The operative technique was performed as follows: A 6-cm curvilinear incision was made along the medial aspect of the proximal phalanx curving beneath the bunion and continuing proximally along the medial border of the ®rst metatarsal, ending 1.5 cm distal to the metatarsocuneiform joint. The incision was deepened and a midline capsular incision was performed which extended proximally to periosteum to » 1.5 cm distal to the metatarsocuneiform joint. The capsule was retracted and the medial eminence was resected in line with the medial border of the metatarsal shaft. A soft tissue release was performed through a dorsal incision over the distal IM 1±2 space. The adductor tendon was identi®ed and released from the base of the proximal phalanx, the lateral sesamoid was freed up on its lateral and plantar border and was released from its dorsal attachments. The transverse intermetatarsal ligament was incised with care taken to avoid injury to the common distal nerve that lies directly beneath this ligament. The contracted lateral metarsophalangeal joint capsule was perforated with several puncture wounds and the toes was gently angulated into 15±20° of varus. The multiple perforations were preferred to a straight incision in order to splay the capsule out along the lateral border of the joint rather than create a gap. The midshaft osteotomy was performed » 1.5 cm from distal to the base of the ®rst metatarsal and was orientated from dorsal-proximal to plantar-distal, ending 1.5±2.0 cm proximal to the sesamoid apparatus (Figure 1). The osteotomy was stabilized with a bone clamp and a Kirschner wire was drilled perpendicular to the osteotomy site from dorsal to plantar just distal to the end of the dorsal cut. The purpose of the wire was to act as a pivotal rotation axis. Once the Kirschner wire was inserted, the bone clamp was removed and the distal end of the metatarsal was rotate laterally on the proximal one to reduce the IM angle (Figure 2). We stress that this is a rotational osteotomy and not a transpositional one. Hence, the distal fragment of the osteotomy is rotated and not displaced. The IM angle reduction was evaluated prior to ®xation. Fixation was accomplished with two screws Ó 2001 Blackwell Science Ltd, Foot and Ankle Surgery 2001, 7, 1±8

Figure 1 Lateral view of the ®rst metatarsal showing the osteotomy line: from dorsal-proximal to plantar-distal.

Figure 2 Dorsal view of the ®rst metatarsal showing the rotation of the cephalic end of the osteotomy.

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Table 1 Objective results (average follow-up: 29.5 months)

IM 1±2 angle HV angle TSP AOFAS Score

Figure 3 Intraoperative picture showing the osteotomy site after ®xation with two screws.

(Biotech InternationalÒ self-tapping canulated compression screws for metatarsal osteotomy) orientated perpendicular to the osteotomy site. The redundant medial bone was removed with a power burr (Figure 3). If required, a proximal phalangeal osteotomy with or without shortening was performed. Fixation was accomplished with a screw, or with a Kirschner wire (Biotech InternationalÒ self-tapping canulated compression screws for metatarsal osteotomy). The medial capsule was repaired and the wounds closed. A dressing was applied to maintain the corrected position of the hallux. Postoperatively, patients were maintained partially weight bearing in a surgical shoe for 4±6 weeks. When union was present on radiographs and postoperative oedema was resolved, patients were allowed to progress to athletic shoes. Active range of motion exercises of the ®rst metatarsal phalangeal joint were started the day after surgery, active strengthening exercises along with proprioceptive exercises were started 4±6 weeks postoperatively. Athletic activity such as running were allowed at 8±10 weeks and jumping activity such as aerobics/ dance were allowed at 10±12 weeks. Swimming was allowed 4±6 weeks postoperatively.

Results The average age at the time of surgery was 43.3 (‹ 14.4 SD) years with a range of 20±65 years. The reader is referred to Table 1 for the summing up of the objective results (Figure 4a±c).

Preop

Postop

19.6°‹ 2.5° 33.8°‹ 5.8° 2.8 ‹ 0.2 48.8 ‹ 14.3

7.7 11.8° 0.6 90.1

‹ ‹ ‹ ‹

3.1° 2.4° 0.6 10.0

Mean correction

P

12.8° 22° 2.2 41.2

<0.05* <0.05* <0.05* <0.05 

IM 1±2 angle = intermetatarsal 1±2 angle. HV angle = hallux valgus angle. TSP = tibial sesamoid position. AOFAS = American Orthopedic Foot and Ankle Society. * Linear regression analysis was used to determine whether a signi®cant correlation was present between the IM 1±2 angle, HV angle, TSP and improved AOFAS Score.   The Student's t-test was used to compare the AOFAS Score before and after the operation.

Union occurred at an average of 6 weeks, no transfer lesions or lesser metatarsal stress fractures were noted. No patient required hardware removal. There were four complications; these included delayed unions and one super®cial wound infection. Two patients (30 + cigarettes/day smokers) sustained delayed unions (3 months) which resolved uneventfully with the use of bone stimulators. One delayed union resulted from non-compliance and full weight bearing soon after surgery; in this case there was some loss of the initial metatarsal correction. Super®cial infection occurred in one patient who was treated successfully with wound care and oral antibiotics. The reader is referred to Table 2 for the summing up of the subjective results. Using the AOFAS Score as a quanti®cation of the above subjective foot evaluation before and after surgery, the score was used in the following manner: The preoperative mean AOFAS Foot Score improved from an average of 48.8/100 (‹ 14.3 SD; range 14±65) to 90.1/100 (‹ 10.0 SD; 60±100) at follow-up (Table 1). This was statistically signi®cant (P < 0.05). There was a signi®cant favourable correlation in the amount of IM 1±2 angle correction (P ˆ 0.021), HV angle correction (P ˆ 0.003) and the TSP correction (P < 0.001) when compared with an increased postoperative AOFAS Foot Score. In other words, there was a trend for an increased angular correction of the metatarsus primus adductus, hallux valgus, and for the correction of the sesamoid subluxation to be correlated with a higher postoperative foot score. Ó 2001 Blackwell Science Ltd, Foot and Ankle Surgery 2001, 7, 1±8

O S T EO TO M Y FO R M I LD H A L LU X V A L G U S

Figure 4 (a) Preoperative dorso-plantar standing radiograph showing severe metatarsus primus varus and hallux valgus deformity. (b) Follow-up dorso-plantar standing radiograph showing the correction of the intermetatarsal 1±2 and the hallux valgus angles obtained with the Ludloff±Akin double osteotomy. (c) Follow-up oblique non-weight bearing radiograph showing the healing of the osteotomy sites. Ó 2001 Blackwell Science Ltd, Foot and Ankle Surgery 2001, 7, 1±8

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Table 2 Subjective results Group (30 feet)

%

Pain relief Totally satis®ed Improved Same Worse

23 5 2 0

76.6 16.6. 6.6 0

Cosmesis Totally satis®ed Improved Same Worse

24 6 0 0

80 20 0 0

Great toe motion No stiffness Noticeable stiffness, not troublesome Stiffness that impairs activity

21 7 2

70 23.3 6.6

Overall satisfaction Satis®ed Dissatis®ed

28 2

93.3 6.6

Trend was de®ned as the general drift, tendency, or bent of a set of statistical data as related to another set of statistical data. There is also a trend (P < 0.001) for a longer follow-up period to be correlated with a better postoperative foot score. Furthermore, we found there was no signi®cant difference (P < 0.05) between the results reported by patients who had additional forefoot procedures (lesser metatarsals and/or lesser toes) performed during the initial surgery (14 feet) and those who did not (16 feet).

Discussion Various authors have stressed that the primary cause of bunion deformity is metatarsus primus adductus (or metatarsus primus varus), with hallux valgus being the secondary deformity [14±16]. Lapidus stressed that the deformity should be corrected at the source, which he thought was the ®rst metatarsal cuneiform joint; he recommended an arthrodesis [14]. Because of the technical demands of this procedure, and the prolonged convalescence, several different procedures have been described to correct the metatarsus primus adductus without arthrodesis. These include proximal procedures [2, 4], diaphyseal multiplane osteotomies [5±8, 10], and distal bony procedures

[15, 17]. The advantages of proximal and midshaft osteotomies over distal procedures to correct higher IM 1±2 angle have been recognized by several authors [2±5, 9, 18]. Proximal osteotomies include Opening and Closing Wedge osteotomies, Crescentic and Chevron osteotomies. Diaphyseal osteotomies include the Scarf or Z osteotomy, Offset-V osteotomy, Mau osteotomy and the Ludloff osteotomy. Among these procedures each one has its own inherent advantages and disadvantages. Ultimately, the preference of any osteotomy will be dependent upon its technical ease of performance, the postoperative course, and the expected sequelae. The technical requirements for basilar osteotomies are demanding [4, 9]. Speci®c problems with the Crescentic bone cut include displacing and ®xing the osteotomy site and evaluation of the ®rst ray [2, 4, 19]. Furthermore, this technique requires a dorsal incision through an area of potential neuroma formation [20]. The Closing Base Wedge osteotomy can lead to signi®cant shortening of the ®rst metatarsal with increased risk of transfer lesions as well as metatarsus elevatus [2, 21, 22]. The Opening Wedge Osteotomy may lengthen the metatarsal initially; dissolution of the bone graft with loss of correction and non-union or malunion can occur with time [2, 23]. Among basilar osteotomies, proximal Chevron osteotomy seems to be associated with a lower rate of complications allowing preservation of the metatarsal length and stability to help prevent metatarsal elevatus [4, 24]. In our opinion, the Ludloff procedure has several advantages over proximal methods, including the ease of displacing and ®xing the osteotomy site and no shortening of the ®rst metatarsal. Both of these issues are essential in the correction of the deformity and in the prevention of painful secondary lesions [9±12]. In recent years, midshaft osteotomies have gained popularity. The Ludloff procedure is a multiplanar rotational osteotomy that can correct various deformities at the same time. This osteotomic con®guration allows for IM angle reduction, metatarsal lengthening and plantar displacement as well as shortening, dorsal displacement and IM angle increase when Ó 2001 Blackwell Science Ltd, Foot and Ankle Surgery 2001, 7, 1±8

O S T EO TO M Y FO R M I LD H A L LU X V A L G U S

indicated (e.g., revision surgery for metatarsal overcorrections). We performed the Ludloff osteotomy to correct the metatarsus primus adductus component of the hallux valgus deformity only in the rectus foot type. A signi®cant hallux valgus deformity may occur even if the IM 1±2 angle is measured as normal [1, 2, 25] due to signi®cant adduction of the metatarsal bones (adductus foot type). In this situation, a rotational osteotomy may over-correct the deformity displacing the metatarsal head too far laterally, creating a negative IM 1±2 angle, which then creates the possibility of a varus of the hallux, as well as an insuf®ciency of the ®rst ray [25, 26]. For correction of the hallux valgus in the adductus foot type, we perform a Scarf cut displacing the cephalic grafment in the dorsoplantar plane: lateral translation without rotation [5, 6]. As stressed earlier, the authors also performed the Ludloff osteotomy with various types of phalangeal osteotomies and soft tissue release, so ultimately the combination of all these procedures determined the radiographic and clinical results. Additional forefoot procedures did not signi®cantly affect the overall outcome based on follow-up foot score pro®les. However, there was a signi®cant difference in the length and disability of the rehabilitative period. We believe that additional forefoot procedures should be performed with caution because those contribute to postoperative oedema. There was a signi®cant favourable correlation in the amount of IM 1±2 angle, HV angle and TSP correction when compared with an increased postoperative foot score; there was also a trend for a

longer follow-up period to be related with a better postoperative foot score. These are important ®ndings because there is a direct correlation here between the improved measurable radiographic parameters and longer follow-up compared to improved subjective evaluation. Complications were noted in four feet (13.3%). This rate compares favourably with other reports on surgical bunion correction [2, 4±7, 9, 11, 19, 21±23]. Two of the patients who sustained delayed unions smoked 30 + cigarettes/day; and delayed/nonunion in smokers has been reported in foot surgery as well as in general orthopaedic surgery [27, 28]. The other patient who suffered delayed union resulted from non-compliance and full weight bearing soon after the procedure. It is important to point out that due to the shape of the bone cut, the osteotomy has no inherent stability to ground reaction forces which could cause dorsal displacement of the distal fragment. Although in our series we did not have such a problem, we had three cases of delayed unions. Mau [8] described the reverse osteotomy, from dorsal distal to plantar proximal producing a plantar shelf to resist the ground reaction forces. Most recently, this procedure was modi®ed with a longer proximal cut entering the metaphyseal bone to allow ®xation with compression screws [9, 29]. Super®cial infection occurred in one patient who was treated successfully with wound care and oral antibiotics. Our data indicate that objective and subjective results are at least as comparable to other proximal and/or midshaft osteotomies (see Table 3). Therefore,

Table 3 Comparison of objective and subjective results between different metatarsal osteotomies IM angle Mean (preop) Crescentic [30] Chevron [4] Closing Wedge [21] Mau [9] Ludloff [11] Ludloff [18] Scarf [5]

HV angle Mean (postop)

IM correction (mean)

Mean (preop)

Mean (postop)

HV correction (mean)

Follow-up (months)

Overall Satisfaction (%) 100 95

14.9° 15°

4.7° 9°

10.2° 6°

35.5° 32°

13.8° 17°

23.7° 15°

24 41

15° 16.1° 15.9° 19.6° NM

12° 5.6° 9.4° 7.7° NM

3.3° 10.5° 6.5° 12.8° 9.1°

31° 35.8° 30.1° 33.8° NM

18° 12.3° 13.4° 11.8° NM

14° 23.5° 16.7° 22° NM

37 14.01 48 29 NM

NM = not mentioned. Ó 2001 Blackwell Science Ltd, Foot and Ankle Surgery 2001, 7, 1±8

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81.5 91 92.9 93.3 98

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the diaphyseal Ludloff technique combined with the distal soft tissue release and, eventually, the Akin osteotomy provides an effective procedure for the treatment of severe bunion deformity associated with metatarsus primus adductus in the rectus foot type.

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Ó 2001 Blackwell Science Ltd, Foot and Ankle Surgery 2001, 7, 1±8