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Management of Valgus Extra-articular Calcaneus Fracture Malunions with a Lateral Opening Wedge Osteotomy Tarek Aly, MD, PhD Department of Orthopedics, Tanta University School of Medicine, Tanta, Egypt article info Level of Clinical Evidence: 3 Keywords: bone graft heel injury peroneal tendon surgery trauma abstract A total of 34 cases of symptomatic valgus deformity of the hindfoot secondary to a malunited extra-articular calcaneal fracture were corrected with laterally based open wedge calcaneal osteotomy. The pre- and post- operative radiographic parameters were compared, and a postoperative clinical evaluation was performed using the American Orthopedic Foot and Ankle Society ankle and hindfoot scoring system. The mean follow-up period was 56.2 (range 24.1 to 97) months. The most signicant radiographic changes were improvement in the talonavicular coverage angle (mean 17.3 ) on the anteroposterior view. The mean postoperative American Orthopedic Foot and Ankle Society hindfoot and ankle score was 90, with 23 excellent, 8 good, and 3 poor results. Laterally based opening wedge osteotomy of the calcaneus is effective in the management of a valgus heel resulting from malunited extra-articular calcaneal fractures. Lateral decompression of the peroneal tendons and the sural nerve was achieved indirectly through opening wedge lateral calcaneal osteotomy that shifted the weight-bearing axis laterally. Ó 2011 by the American College of Foot and Ankle Surgeons. All rights reserved. Inadequate or inappropriate primary treatment of a fracture of the calcaneus frequently results in persistent pain in the foot. Painful sequelae, which are common after fractures of the calcaneus, vary. They can be the result of complications related to nerves, subtalar osteoarthrosis, impingement on a tendon or other soft tissue, calca- neobular abutment, altered mechanics of the tibiotalar joint, an unrecognized compartment syndrome, chronic pain syndrome (e.g., reex sympathetic dystrophy), and the so-called smashed heel-pad syndrome. The therapeutic approaches to these conditions have included shoe modications, physiotherapy, operative reconstruction, judicious, sensory denervation of the heel, and, even, amputation (1). Malunion is a common difculty resulting from the nonoperative treatment of displaced, calcaneal fractures (2). Regardless of the method of treatment selected for calcaneal fractures, mobility can be limited in the presence of a decreased calcaneal body height, calca- neobular abutment, attening of the longitudinal arch, and teno- synovitis of the peroneal tendons when they are compressed against the bula by a widened calcaneal body. Osteotomy of the calcaneus was advocated by Edwards and Menelaus (3), who described its use in 5 patients who had congenital calcaneovalgus deformity (oblique osteotomy of tuberosity of the calcaneum with medial displacement of the tuberosity of about 1.5 cm). Evans (4) and Pandey et al. (5) also reported its use, mainly for deformities of the foot, rather than for the calcaneus, that develop from paresis of the triceps surae. Mosca (6) used open wedge osteotomy of the cuneform bone to treat at feet secondary to a variety of causes with very good results. Clinically, it results in a correction of both hind foot and midfoot valgus, with an associated improvement in the medial longitudinal arch (7). The purpose of the present study was to analyze the clinical and radiographic outcomes of laterally based open wedge osteotomy to realign a valgus calcaneal deformity and subsequently improve the mid-tarsal joint alignment of malunited extra-articular calcaneal fractures. Patients and Methods From December 1999 to June 2006, 28 patients (34 feet) with symptomatic feet secondary to malunited extra-articular calcaneal fractures leading to valgus deformity of the heel with no or mild subtalar arthritis underwent lateral opening wedge calcaneal osteotomy. All the patients had pain in the foot or ankle, or both, as a resultof the fracture, which had occurred at a mean of 28 (range 9 to 35) months before they were seen by us for treatment. Of the 28 patients, 24 were men and 4 were women. The mean patient age at surgery was 34.7 (range 23.9 to 51.3) years. Of these 28 patients, 6 underwent bilateral procedures. Most of the injuries had been sustained in a fall from a height (23 patients). A motor vehicle accident was the cause of the fracture in 5 patients. All patients had undergone a trial of nonoperative treatment that included orthotics, shoe modication, activity modication, and nonsteroidal anti-inammatory medication. Despite these treatments, they continued to be symptomatic to the degree that it was interfering with their ability to participate in activities of daily living. The Financial Disclosure: None reported. Conict of Interest: None reported. Address correspondence to: Tarek Aly, MD, PhD, Assistant Professor of Orthopedic Surgery, Tanta University School of Medicine, 48th Sarwat Street, Tanta 31111 Egypt. E-mail address: [email protected] 1067-2516/$ - see front matter Ó 2011 by the American College of Foot and Ankle Surgeons. All rights reserved. doi:10.1053/j.jfas.2011.04.006 Contents lists available at ScienceDirect The Journal of Foot & Ankle Surgery journal homepage: www.jfas.org The Journal of Foot & Ankle Surgery 50 (2011) 703706

Management of Valgus Extra-articular Calcaneus Fracture Malunions with a Lateral Opening Wedge Osteotomy

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The Journal of Foot & Ankle Surgery 50 (2011) 703–706

Contents lists avai

The Journal of Foot & Ankle Surgery

journal homepage: www.j fas .org

Management of Valgus Extra-articular Calcaneus Fracture Malunionswith a Lateral Opening Wedge Osteotomy

Tarek Aly, MD, PhDDepartment of Orthopedics, Tanta University School of Medicine, Tanta, Egypt

a r t i c l e i n f o

Level of Clinical Evidence: 3Keywords:

bone graftheelinjuryperoneal tendonsurgerytrauma

Financial Disclosure: None reported.Conflict of Interest: None reported.Address correspondence to: Tarek Aly, MD, PhD, A

Surgery, Tanta University School of Medicine, 48th SaE-mail address: [email protected]

1067-2516/$ - see front matter � 2011 by the Americdoi:10.1053/j.jfas.2011.04.006

a b s t r a c t

A total of 34 cases of symptomatic valgus deformity of the hindfoot secondary to a malunited extra-articularcalcaneal fracture were corrected with laterally based open wedge calcaneal osteotomy. The pre- and post-operative radiographic parameters were compared, and a postoperative clinical evaluation was performedusing the American Orthopedic Foot and Ankle Society ankle and hindfoot scoring system. The mean follow-upperiod was 56.2 (range 24.1 to 97) months. The most significant radiographic changes were improvement inthe talonavicular coverage angle (mean 17.3�) on the anteroposterior view. The mean postoperative AmericanOrthopedic Foot and Ankle Society hindfoot and ankle score was 90, with 23 excellent, 8 good, and 3 poorresults. Laterally based opening wedge osteotomy of the calcaneus is effective in the management of a valgusheel resulting from malunited extra-articular calcaneal fractures. Lateral decompression of the peronealtendons and the sural nerve was achieved indirectly through opening wedge lateral calcaneal osteotomy thatshifted the weight-bearing axis laterally.

� 2011 by the American College of Foot and Ankle Surgeons. All rights reserved.

Inadequate or inappropriate primary treatment of a fracture of thecalcaneus frequently results in persistent pain in the foot. Painfulsequelae, which are common after fractures of the calcaneus, vary.They can be the result of complications related to nerves, subtalarosteoarthrosis, impingement on a tendon or other soft tissue, calca-neofibular abutment, altered mechanics of the tibiotalar joint, anunrecognized compartment syndrome, chronic pain syndrome (e.g.,reflex sympathetic dystrophy), and the so-called smashed heel-padsyndrome. The therapeutic approaches to these conditions haveincluded shoemodifications, physiotherapy, operative reconstruction,judicious, sensory denervation of the heel, and, even, amputation (1).Malunion is a common difficulty resulting from the nonoperativetreatment of displaced, calcaneal fractures (2). Regardless of themethod of treatment selected for calcaneal fractures, mobility can belimited in the presence of a decreased calcaneal body height, calca-neofibular abutment, flattening of the longitudinal arch, and teno-synovitis of the peroneal tendons when they are compressed againstthe fibula by a widened calcaneal body.

Osteotomy of the calcaneus was advocated by Edwards andMenelaus (3), who described its use in 5 patients who had congenitalcalcaneovalgus deformity (oblique osteotomy of tuberosity of the

ssistant Professor of Orthopedicrwat Street, Tanta 31111 Egypt.

an College of Foot and Ankle Surgeon

calcaneum with medial displacement of the tuberosity of about1.5 cm). Evans (4) and Pandey et al. (5) also reported its use, mainly fordeformities of the foot, rather than for the calcaneus, that developfrom paresis of the triceps surae. Mosca (6) used open wedgeosteotomy of the cuneform bone to treat flat feet secondary toa variety of causes with very good results. Clinically, it results ina correction of both hind foot and midfoot valgus, with an associatedimprovement in the medial longitudinal arch (7).

The purpose of the present study was to analyze the clinical andradiographic outcomes of laterally based open wedge osteotomy torealign a valgus calcaneal deformity and subsequently improve themid-tarsal joint alignment of malunited extra-articular calcanealfractures.

Patients and Methods

From December 1999 to June 2006, 28 patients (34 feet) with symptomatic feetsecondary tomalunited extra-articular calcaneal fractures leading tovalgus deformity ofthe heel with no or mild subtalar arthritis underwent lateral opening wedge calcanealosteotomy.All thepatientshadpain in the footorankle, or both, as a resultof the fracture,which had occurred at a mean of 28 (range 9 to 35) months before they were seen by usfor treatment. Of the 28 patients, 24 were men and 4 were women. The mean patientage at surgery was 34.7 (range 23.9 to 51.3) years. Of these 28 patients, 6 underwentbilateral procedures. Most of the injuries had been sustained in a fall from a height(23 patients). A motor vehicle accident was the cause of the fracture in 5 patients.

All patients had undergone a trial of nonoperative treatment that includedorthotics, shoe modification, activity modification, and nonsteroidal anti-inflammatorymedication. Despite these treatments, they continued to be symptomatic to the degreethat it was interfering with their ability to participate in activities of daily living. The

s. All rights reserved.

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T. Aly / The Journal of Foot & Ankle Surgery 50 (2011) 703–706704

subtalar joint range of movement was restricted in 27 feet. The pain was mostcommonly in the region of the peroneal tendons and the medial longitudinal arch.

The indications for surgery included calcaneal valgus deformity interfering withpatient daily life activities without subtalar arthritis. The operation was done within 1year of the original injury.

Fig. 1. Photograph showing osteotomy site, with posterior aspect of heel pointing up.

Clinical Evaluation

All patients were evaluated before and after surgery using the American OrthopedicFoot and Ankle Society (AOFAS) hindfoot and ankle scoring system (8). This is a 100-point scale, with 40 points for pain, 50 for function, and 10 for alignment. A score of 90to 100 was considered excellent, 80 to 89 good, 70 to 79 fair, and less than 70 poor.Examination of the foot and ankle included measurement of the range of dorsiflexion-plantar flexion and inversion-eversion of the ankle, hindfoot, and forefoot. The site orsites of maximum tenderness were evaluated by palpation of the soft tissues andthrough assessment of pain on attempted active range of motion of the ankle and thesubtalar and transverse tarsal joints. The physical examinationwas supplemented withselective blocks of joints and soft tissue using xylocaine and bupivacaine. This was doneto better localize the exact source of pain when it had been difficult to determine.

Radiologic Evaluation

Weight-bearing anteroposterior, lateral, and axial radiographs of the foot wereobtained for all patients preoperatively and at every postoperative follow-up visit at 6weeks and 3 months and then every 6 months. The measurements were performed ina similar manner on all radiographs according to themethod of Sangeorzan et al. (9). Onthe anteroposterior film, we measured the talocalcaneal angle and the talonavicularcoverage angle, which measure the amount of subluxation of the navicular. A line wasdrawn connecting the border of the articular surface of the talus and a perpendicularline was made at the midpoint. A second line was drawn connecting the border of thearticular surface of the navicular and a perpendicular drawn to it. The angle betweenthe perpendicular lines was defined as the talonavicular coverage angle. On the lateralview, 2measurements weremade. First, the talocalcaneal anglewasmeasured betweenthe long axis of the talus and calcaneus. The angle between the long axis of the talusand the lateral border of the calcaneus. The angle decreases when varus angulation ofthe hindfoot is present or when the foot is in dorsiflexion. The talocalcaneal angleincreases with valgus or plantar flexion (10, 11). Second, the calcaneal length wasmeasured from the most posterior point of the tuberosity to the calcaneocuboid joint.The height of the posterior facet is measured by a line perpendicular on the calcanealaxis to the highest point of the posterior facet (12). The hindfoot alignment viewprovides a coronal plane evaluation of the hindfoot in relation to the distal tibia. Aspecial roentgenogram of the hind part of the foot, modified from that described byCobey, was made with the patient standing upright with the knees extended and awayfrom the x-ray beam, which was directed downward at a 20� angle from the horizontalto a vertically oriented x-ray cassette. This roentgenogram allowed accurate delineationof the angle that was formed by the long axis of the tibia and the vertical axis of thecalcaneus (13).

The radiographs were useful for the diagnosis and delineation of the severity of theosteoarthrosis (subtalar or transverse tarsal). All radiographic measurements wereassessed by myself and 1 radiologist using a computerized digitizer.

Fig. 2. Trapezoidal iliac bone graft placed in osteotomy site, which was filled with bonetaken from lateral calcaneal shaving, with posterior aspect of heel pointing up.

Surgical Technique

The lateral opening wedge calcaneal osteotomy is approached through an obliquelateral incision. Superficial branches of the peroneal nerve are protected and retracted.The middle facet of the subtalar joint (the sustentaculum tali) is identified by probingover the dorsum of the exposed calcaneus.

The lateral border of the widened calcaneus is shaved. The periosteum is incised inline with the planned osteotomy, starting laterally approximately 2.5 cm proximal tothe calcaneocuboid joint in the interval between the middle and posterior facets of thesubtalar joint.

A lateral to medial oblique osteotomy is accomplished using power-driveninstrumentation (Fig. 1). The osteotomy line is taken slightly oblique from proximallyand laterally to distally and medially. Preoperatively, the required depth of theosteotomy is estimated from the calcaneal axial radiographs. A large osteotome is thenused to open the osteotomy. The periosteum of the medial calcaneus should bepreserved to prevent medial displacement of the posterior fragment. Once the deter-mined width of the opening is achieved, a suitable tricortical bone graft taken from theposterior iliac crest is placed in the osteotomy site plus the bone that was taken fromthe lateral calcaneal shaving (Fig. 2). Fixation is obtained with one cannulated screwthrough the posterior approach along the long axis of the calcneus.

Postoperatively, non–weight-bearing in a cast was advised for 6 weeks, followed bya walking cast for another 6 weeks before the patients were allowed to wear normalshoes.

Statistical Evaluation

The statistical comparison was made using the paired Student’s t test to comparethe pre- and postoperative values. The tests that yielded p < .05 were considered todemonstrate statistically significant differences.

Results

All patients were available for radiographic and clinical evaluationat the final follow-up visit. The mean follow-up period was 56.2(range 27 to 97) months. The results of the operation were evaluatedusing the AOFAS score. The ability to return to the previous occupa-tion or to the preinjury level of activity was carefully assessed.

Radiographic Evaluation

Postoperative radiographs showed the following improvementscompared with preoperative values. On the anteroposterior view, thetalocalcaneal angle improved from a mean of 21.4� (range 16.6� to24.5�) preoperatively to 38.3� (range 29� to 41.3�) postoperatively. Thetalonavicular coverage angle improved from 24.5� (range 19.2� to27.4�) preoperatively to 7.2� (range 6.5� to 10.6�) postoperatively. Onthe lateral view, similar improvement was seen. The lateral talo-calcaneal angle improved from 23� (range 16.4� to 27.8�) preopera-tively to 34.4� (range 32.7� to 45.8�) postoperatively. The length of thecalcaneus increased 73.6 mm preoperatively to 80.9 mm post-operatively, and the calcaneal height improved from 44 mm preop-eratively to 49 mm postoperatively (Figs. 3 and 4). The tibiocalcanealangle (measured in the hindfoot view) improved from 32.4� preop-eratively (range 23.8� to 45.7�) to 6.2� (range 7.3� valgus to 5.4� varus)postoperatively. All differences in the angles between the preopera-tive measurements and at follow-up were significant, except for the

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Table 1Summary of mean pre- and postoperative radiographic data and p values determinedby paired t tests (N ¼ 34 feet in 28 patients)

Parameter Preoperative Postoperative p value

Talocalcaneal angle 21.4 38.3 .001Talonavicular coverage 24.5 7.2 .0002Talocalcaneal angle 23.0 34.4 .0222Calcaneal length 73.6 80.9 < .0001Calcaneal height 44 49 .001

Fig. 3. Preoperative lateral weight-bearing radiograph.

T. Aly / The Journal of Foot & Ankle Surgery 50 (2011) 703–706 705

lateral talocalcaneal angle. Also, of the distances measured, all thedifferences were statistically significant (Table 1).

All bone grafts united with the calcaneus within 2 months.Complete incorporation and remodeling occurred within 1 year.

Clinical Evaluation

Clinically, the valgus deformity of the hindfoot had been correctedin all patients. All patients return to their previous work at a mean of4 (range 3 to 7) months. The mean AOFAS hindfoot and ankle scorewas 57 (range 35 to 60) preoperatively and improved to 90 (range 69to 100) postoperatively. Of the 34 feet, 23 (67.7%) had excellent results(Figs. 5 and 6), 8 (23.5%) had good results, and 3 (8.8%) poor results.The pain in the foot had disappeared completely in 14 feet (41.2%) andwas mild and occasional in 20 (58.8%). The patients’ walking abilitywas improved to walking more than a 6-block walking distance in 24patients (85.7%). Two patients had a 4-block walking ability (7.2%),1 (3.6%) had a 2-block walking ability, and 1 could walk for only 1block. Only 2 patients had an obvious gait abnormality. These 2patients had had bilateral calcaneal fractures with bilateral subtalararthritis. The hindfoot motionwas moderately restricted in 3 patients(8.8%) who had had bilateral calcaneal fractures with subtalar arthritisof 1 foot, with poor results for that foot.

Discussion

Most reports of fractures of the calcaneus have been reviews ofseries of fractures for which the initial treatment had consisted ofopen procedures or had been nonoperative. Most of the investigatorsdid not offer recommendations on how to treat patients for whom theprimary treatment had failed (14–16). The complications of malunion

Fig. 4. Postoperative lateral radiograph taken at 2 months follow-up.

include a loss of height of the heel, with concomitant dorsiflexion ofthe talus, widening of the heel, lateral impingement of the peronealtendons and the distal fibula, and subtalar post-traumatic arthritis.

Pain and disability often persist after fractures of the calcaneus,even though the original injury was treated skillfully (17, 18). This isespecially likely if the patient’s occupation requires walking overrough ground. The cause is usually an incongruity or malalignment ofthe hindfoot, resulting in altered patterns of shoe wear and gait,traumatic arthritis of the subtalar joint, or abnormalities about theperoneal tendons.

To improve the outcomes in these patients, the treatment mustfocus on correction of the specific anatomic problems encountered.The primary fracture is a shearing fracture that runs obliquely downthe length of the calcaneus from superolateral to inferomedial andanterolateral to posteromedial. This permits the tuberosity of thecalcaneus to translate laterally and proximally and often splits theposterior facet. When eversion of the heel from a valgus deformity ismarked, foot strain is likely.

Evans (4) believed that the lateral column is the foundation of theskeletal structure of the foot. He observed that equinovarus deformityof a clubfoot was correctable by shortening of the lateral column andthat the calcaneovalgus position of an overcorrected clubfoot could beobtained by lengthening of the lateral column with a bone graft. Thisled him to believe that the length of the lateral column relative to themedial column has a major influence on the shape of the foot.Kalamchi and Evans (19) combined the Gallie arthrodesis (20) withthe technique of Conn (21) and stated that the trapezoidal slot for thegraft allowed for correction of valgus of the heel, thereby fusing theheel in a neutral position.

The high rate of success associated with lengthening of the lateralcolumn in children for treatment of flat feet (6) and the poor long-term results of triple arthrodesis in adults (22) led us to adopt theprincipal of Evans (4) for the treatment of symptomatic malunitedcalcaneal fractures with a valgus heel.

Lengthening of the lateral column markedly improved the defor-mities of the foot in the transverse and sagittal planes. A comparisonof the pre- and postoperative radiographs in the standing position

Fig. 5. Posterior standing view. Preoperative clinical appearance of calcaneal fracture ofleft foot showing valgus position of hindfoot and dropping of medial longitudinal arch.

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Fig. 6. Postoperative clinical appearance of calcaneal fracture of same foot showinghindfoot deformity correction and reforming of medial longitudinal arch. Photographtaken at 3 months follow-up.

T. Aly / The Journal of Foot & Ankle Surgery 50 (2011) 703–706706

showed a significant correction of the parameters that weremeasured. These corrections are in agreement with those reported forflat feet correction (9, 23). The marked decreases in these anglesconfirmed that lengthening of the lateral column effectively correctsthe malalignment of the midfoot and hindfoot associated with mal-united calcaneal fractures. The significant correction of the calcaneallength seen on the lateral radiographs, with no change in the talo-calcaneal angle, suggests that lengthening of the lateral columninverts the calcaneus out of the planovalgus deformity and indirectlyrelieves compression on the lateral structures, sural nerve, andperoneal tendons, because of the shift in the contact area and pressuretime integral from medial to lateral (7).

The differences in the types of the original injuries and the degreesof severity and the variations in treatment made it difficult tocompare the results of the several groups of patients in the presentstudy. We believe, however, that 1 critical criterion in such an eval-uation is the patient’s return to their previous occupation or activitylevel. This is particularly true because most fractures of the calcaneusare the result of work-related accidents.

The AOFAS scores demonstrated excellent outcomes comparedwith those preoperatively, and the scores demonstrated a trendtoward improvement with time. Good results were found for allpatients examined at less than 6 months postoperatively. Althoughthe patients with poor results had good pain relief and improvementin most radiographic parameters, they had poor motion in the sub-talar complex, as well as a persistent flat foot deformity. This wasunchanged from the preoperative motion when reviewed retrospec-tively in their charts. This suggested that the procedure would beexcellent if it could be done before arthritic changes have occurred inthese joints.

In conclusion, opening wedge calcaneal osteotomy providedexcellent relief of lateral pain in patients with symptomatic malunitedcalcaneal fractures with valgus heel before the appearance of arthriticchanges in the subtalar joint, with a significant radiographic correc-tion of the hindfoot valgus and correction of the longitudinal arch.

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