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Factors Associated With Recurrent Fifth Metatarsal Stress Fracture Kyung-tai Lee, Young-uk Park, Hyuk Jegal, Ki-chun Kim, Ki-won Young and Jin-su Kim Foot Ankle Int 2013 34: 1645 originally published online 11 November 2013 DOI: 10.1177/1071100713507903 The online version of this article can be found at: http://fai.sagepub.com/content/34/12/1645
Published by: http://www.sagepublications.com
On behalf of:
American Orthopaedic Foot & Ankle Society
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research-article2013
FAIXXX10.1177/1071100713507903Foot & Ankle InternationalLee et al
Article
Factors Associated With Recurrent Fifth Metatarsal Stress Fracture
Foot & Ankle International 34(12) 1645–1653 © The Author(s) 2013 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/1071100713507903 fai.sagepub.com
Kyung-tai Lee, MD, PhD1, Young-uk Park, MD, PhD2, Hyuk Jegal, MD1, Ki-chun Kim, MD3, Ki-won Young, MD, PhD4, and Jin-su Kim, MD, PhD4
Abstract Background: Many surgeons agree that fifth metatarsal stress fractures have a tendency toward delayed union, nonunion, and possibly refracture. Difficulty healing seems to be correlated with fracture classification. However, refracture sometimes occurs after low-grade fracture, even long after apparent resolution. Methods: The records of 168 consecutive cases of fifth metatarsal stress fracture (163 patients) treated by modified tension band wiring from March 2002 to June 2011 were evaluated retrospectively. Mean length of follow-up was 23.6 months (range, 10-112 months). Forty-nine cases classified as Torg III were bone grafted initially also. All enrolled patients were elite athletes. Eleven patients experienced nonunion and 18 refracture. The 11 nonunion cases were bone grafted. The 157 patients (excluding nonunion cases) were allocated to either a refracture group or a union group. Clinical features, such as age, weight, fracture classification, time to union, and reinjury history, were compared. Radiological parameters representing cavus deformity and fifth metatarsal head protrusion were compared to evaluate the influence of structural abnormalities. Results: Mean group weights were significantly different (P = .041), but mean ages (P = .879), fracture grades (P = .216, P = .962), and time from surgery to rehabilitation (P = .539) were similar. No significant intergroup differences were found for talocalcaneal (TC) angle (P = .470), calcaneal pitch (CP) angle (P = .847), or talo–first metatarsal (T-MT1) angle (P = .407) on lateral radiographs; for fifth metatarsal lateral deviation (MT5-LD) angle (P = .623) on anteroposterior (AP) radiographs; or for MT5-LD angle (P = .065) on the 30-degree medial oblique radiographs. However, the mean fourth-fifth intermetatarsal (IMA4-5) angle on AP radiographs was significantly greater in the refracture group, and for Torg II cases, mean weight (P = .042), IMA4-5 angle on AP radiographs (P = .014), and MT5-LD angle (P = .043) on 30-degree medial oblique radiographs were significantly greater in the refracture group. For B2 cases (incomplete fracture and a plantar gap of 1 mm or larger), mean weight (P = .046), IMA4-5 angle on AP radiographs (P = .019), and MT5-LD angle (P = .045) on 30-degree medial oblique radiographs were significantly greater in the refracture group. All cases of refracture had a traumatic history after bone union. Refracture developed within 6 months of starting rehabilitation in 13 cases and within 3 months in 8 cases. Conclusion: The development of refracture after the surgical treatment of fifth metatarsal stress fractures was found to be associated with higher body mass index (BMI) and with radiological parameters (IMA4-5 on AP radiographs, MT5-LD on oblique radiographs) associated with protrusion of the fifth metatarsal head. The study indicates that patients with a protruding fifth metatarsal head and a high BMI should approach rehabilitation with care before considering a return to previous sporting activity levels. Level of Evidence: Level III, retrospective comparative series. Keywords: fifth metatarsal, stress fracture, refracture, causative factor
Introduction
1
Fractures located at the metaphyseal-diaphyseal junction at the base of the fifth metatarsal were first described by Sir Robert Jones8 in 1902, who reported on 4 fifth-metatarsal fractures, including a personal fracture that occurred while dancing. Much has since been written about fractures of the base of the fifth metatarsal, and considerable controversy remains regarding diagnosis, classification, pathomechanics,
KT Lee’s Orthopedic Hospital, Seoul, Republic of Korea Ajou University Hospital, Gyeonggi-do, Republic of Korea 3 Seoul Medical Center, Seoul, Republic of Korea 4 Eulji Medical Center, Eulji University School of Medicine, Foot and Ankle Clinic, Seoul, Republic of Korea 2
Corresponding Author: Young-uk Park, MD, PhD, Ajou University Hospital, 164 World Cup Road, Yeongtong-gu, Gyeonggi-do, 443-380, Republic of Korea. Email: [email protected]
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Figure 1. Torg classification of fifth metatarsal stress fracture. Type I is defined as an acute fracture on a chronic process with evidence of prior periosteal reaction and absence of medullary sclerosis. Type II shows a similar process; however, medullary sclerosis and narrowing consistent with delayed union are present. Type III fractures are those with obliteration of the medullary canal and are classified as nonunions.
the incidences and potential causes of delayed unions and nonunions, and the optimal method of treatment. The treatment of fractures of the proximal fifth metatarsal diaphysis (Jones fractures) can be challenging and at times can result in significant disability, especially in elite athletes. Dameron2 was the first to suggest that the treatment of Jones fractures in athletes should receive additional considerations, and subsequently others have reported high rates of refracture and delayed union after treatment in athletes.1,3,10,13,21 It appears to be widely agreed that proximal fractures of the metaphyseal/diaphyseal region of the fifth metatarsal (excluding avulsion fractures) are prone to delayed union or even nonunion.2,3,10,14,20 Complications including delayed union and nonunion and extensive non-weight-bearing time led some researchers to devise a classification system that can be used to determine surgical technique and predict outcome for fifth metatarsal Jones fractures. Torg et al20 classified fractures involving the proximal part of the diaphysis of the fifth metatarsal into 3 subtypes. Type I fractures are acute fractures visualized radiographically as a narrow fracture line and the absence of intramedullary sclerosis. Type II fractures show delayed union, widening of the fracture line, and evidence of intramedullary sclerosis on plain radiographs. Type III fractures exhibit nonunion with widening of the fracture line and complete medullary canal obliteration by sclerotic bone (Figure 1). Lee et al12 classified fractures involving the proximal part of the diaphysis of the fifth metatarsal into 2 groups according to fracture morphology and the presence or absence of a plantar gap of greater than 1 mm. Group A (the complete fracture group) had a fracture line clearly extending to the medial and dorsal cortex) and Group B
(incomplete fracture group) had a fracture line limited to the plantar lateral area of the fifth metatarsal bone without progression to the medial and dorsal cortex. Patients in group A were subdivided into 2 groups by fracture morphology, that is, group A1 (acute fracture) or group A2 (acute on chronic fracture). Patients in group B were also subdivided into 2 groups by plantar gap, that is, group B1 (incomplete fracture and a plantar gap of less than 1 mm) or group B2 (incomplete fracture and a plantar gap of 1 mm or larger) (Figure 2). According to some studies, nonunion seems to be correlated with fracture severity,13 and thus classification systems have prognostic value in terms of predicting the risk of nonunion. However, refracture occurs sometimes following fractures of low grade, even a long time after the achievement of union. Furthermore, some researchers have stated that fifth metatarsal stress fracture is correlated with cavus deformity.11 Raikin et al17 reported that varus hindfoot alignment might be a predisposing factor to development of fracture or refracture after fixation. No comparison study has been performed on the cause of refracture after surgical treatment of fifth metatarsal stress fracture. Accordingly, the present study was undertaken to identify causative structural abnormalities and other factors for refracture of fifth metatarsal stress fractures.
Methods This retrospective study was approved by our institutional review board. Between March 2002 and June 2011, 168 cases of fifth metatarsal stress fracture (163 patients) were treated using modified tension band wiring. Mean length of follow up was 23.6 months (range, 10-112 months). This
Downloaded from fai.sagepub.com at UNIV MASSACHUSETTS BOSTON on September 1, 2014
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Lee et al
Figure 2. Lee et al classification of fifth metatarsal stress fracture. Group A (complete fracture group, fracture line clearly seen extending to the medial and dorsal cortex) and Group B (incomplete fracture group, fracture line limited to plantar lateral area of the fifth metatarsal bone, without progression to the medial and dorsal cortex). Group A was subdivided into 2 groups according to fracture morphology: group A1 (acute fracture) and group A2 (acute on chronic fracture). Group B was subdivided into 2 groups according to the plantar gap: group B1 (incomplete fracture, plantar gap less than 1 mm) and group B2 (incomplete fracture, plantar gap 1 mm or larger).
consecutive series of patients included 159 men and 4 women of mean age 19.6 years (range, 13-33 years) at surgery. Of these, 11 experienced nonunion and 18 refracture. Among the 163 patients, 80 were right sided, 78 were left sided, and 5 were bilateral. One hundred fifty-nine patients were soccer players, 1 was a hockey player, 1 was a rugby player, and 2 were basketball players. All patients were treated using modified tension band wiring, and inlay bone grafting was used in cases of Torg type III fractures. Patients were then immobilized in a short leg splint. Postoperatively, the patients were instructed not to bear weight and to use a short leg cast for 6 weeks. Then, they were placed into a walking boot with progressive weight-bearing as tolerated. All athletes were allowed to return to unrestricted activity when they were clinically asymptomatic and when they showed progress in bone union, as indicated on radiographs followed by computed tomography (CT) scans. For patients with signs of progressive union, CT scan was routinely repeated about 2 months after the operation. Treatment results were evaluated by retrospectively reviewing hospital records and radiographs. Bone union was considered to have been achieved when the cortical continuity of the plantar side of the fracture gap (plantar gap) was reestablished with callus on a CT scan. There were 11 cases of nonunion, which was defined as the absence of visible progressive signs of healing for 3 months regardless of symptoms. Nine nonunion cases were Torg type II and 2 were Torg type III (Figure 1). According to the classification by Lee et al (Figure 2), there was 1
complete fracture (A1, compete and acute) and 10 incomplete fractures (B2, incomplete, plantar gap larger than 1 mm). In nonunion cases, autogenous bone grafting was performed after hardware removal. A rectangular section of bone centered over the fracture was removed with a sharp osteotome. An autogenous corticocancellous bone graft was then removed from the anterior process of the calcaneus through a second incision; care was taken to contour the graft so that the cortical portion of the graft accurately fit into the rectangular cortical defect. There were 18 cases of refracture: 6 Torg type I, 7 type II, and 5 type III. According to the classification by Lee et al, there were 4 type A1, 1 type A2, 4 type B1, and 9 type B2. Patients were allocated to a refracture group (n = 18) or a union group (n = 139), after we excluded cases of nonunion. These 2 groups were compared with respect to clinical features, which included age, weight, body mass index (BMI), classification, union time, and reinjury history. Each case was classified according to the Torg classification and the Lee et al classification. Fourth-to-fifth intermetatarsal (IMA4-5) angle and fifth metatarsal lateral deviation (MT5-LD) angle were measured on standing anteroposterior (AP) radiographs (Figure 3). Talo–first metatarsal (T-MT1) angle, talocalcaneal (TC) angle, and calcaneal pitch (CP) angle were measured on standing lateral views, and MT5-LD angle was measured on 30-degree medial oblique views (Figure 3). Radiographic features were compared to evaluate the effects of structural abnormalities such as cavovarus deformity.
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Foot & Ankle International 34(12)
Figure 3. Fourth-to-fifth intermetatarsal angle: the angle subtended by the intersecting axes of the fourth and fifth metatarsals. Fifth metatarsal lateral deviation: the angle created by a line bisecting the midpoint of the articular surface of the head and the neck of the fifth metatarsal and line adjacent and parallel to the medial surface of the proximal metatarsal.
Surgical Technique Two cortical screws (diameter, 2.7 mm) were placed on the proximal and distal fragment, 1 cm away from the fracture site more on the plantar side, since it is the tension side. The screw hole was deepened using a countersink to avoid irritation from a prominent screw head. Using the reduction clamp on the screws, the fracture was compressed and a wire loop was tightened around the screws in a figure-ofeight fashion. Then, 2 screws were retightened.
Statistical Analysis Statistical significance was accepted for P values of
Factors Associated With Recurrent Fifth Metatarsal Stress Fracture Kyung-tai Lee, Young-uk Park, Hyuk Jegal, Ki-chun Kim, Ki-won Young and Jin-su Kim Foot Ankle Int 2013 34: 1645 originally published online 11 November 2013 DOI: 10.1177/1071100713507903 The online version of this article can be found at: http://fai.sagepub.com/content/34/12/1645
Published by: http://www.sagepublications.com
On behalf of:
American Orthopaedic Foot & Ankle Society
Additional services and information for Foot & Ankle International can be found at: Email Alerts: http://fai.sagepub.com/cgi/alerts Subscriptions: http://fai.sagepub.com/subscriptions Reprints: http://www.sagepub.com/journalsReprints.nav Permissions: http://www.sagepub.com/journalsPermissions.nav
>> Version of Record - Dec 6, 2013 OnlineFirst Version of Record - Nov 11, 2013 What is This?
Downloaded from fai.sagepub.com at UNIV MASSACHUSETTS BOSTON on September 1, 2014
507903
research-article2013
FAIXXX10.1177/1071100713507903Foot & Ankle InternationalLee et al
Article
Factors Associated With Recurrent Fifth Metatarsal Stress Fracture
Foot & Ankle International 34(12) 1645–1653 © The Author(s) 2013 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/1071100713507903 fai.sagepub.com
Kyung-tai Lee, MD, PhD1, Young-uk Park, MD, PhD2, Hyuk Jegal, MD1, Ki-chun Kim, MD3, Ki-won Young, MD, PhD4, and Jin-su Kim, MD, PhD4
Abstract Background: Many surgeons agree that fifth metatarsal stress fractures have a tendency toward delayed union, nonunion, and possibly refracture. Difficulty healing seems to be correlated with fracture classification. However, refracture sometimes occurs after low-grade fracture, even long after apparent resolution. Methods: The records of 168 consecutive cases of fifth metatarsal stress fracture (163 patients) treated by modified tension band wiring from March 2002 to June 2011 were evaluated retrospectively. Mean length of follow-up was 23.6 months (range, 10-112 months). Forty-nine cases classified as Torg III were bone grafted initially also. All enrolled patients were elite athletes. Eleven patients experienced nonunion and 18 refracture. The 11 nonunion cases were bone grafted. The 157 patients (excluding nonunion cases) were allocated to either a refracture group or a union group. Clinical features, such as age, weight, fracture classification, time to union, and reinjury history, were compared. Radiological parameters representing cavus deformity and fifth metatarsal head protrusion were compared to evaluate the influence of structural abnormalities. Results: Mean group weights were significantly different (P = .041), but mean ages (P = .879), fracture grades (P = .216, P = .962), and time from surgery to rehabilitation (P = .539) were similar. No significant intergroup differences were found for talocalcaneal (TC) angle (P = .470), calcaneal pitch (CP) angle (P = .847), or talo–first metatarsal (T-MT1) angle (P = .407) on lateral radiographs; for fifth metatarsal lateral deviation (MT5-LD) angle (P = .623) on anteroposterior (AP) radiographs; or for MT5-LD angle (P = .065) on the 30-degree medial oblique radiographs. However, the mean fourth-fifth intermetatarsal (IMA4-5) angle on AP radiographs was significantly greater in the refracture group, and for Torg II cases, mean weight (P = .042), IMA4-5 angle on AP radiographs (P = .014), and MT5-LD angle (P = .043) on 30-degree medial oblique radiographs were significantly greater in the refracture group. For B2 cases (incomplete fracture and a plantar gap of 1 mm or larger), mean weight (P = .046), IMA4-5 angle on AP radiographs (P = .019), and MT5-LD angle (P = .045) on 30-degree medial oblique radiographs were significantly greater in the refracture group. All cases of refracture had a traumatic history after bone union. Refracture developed within 6 months of starting rehabilitation in 13 cases and within 3 months in 8 cases. Conclusion: The development of refracture after the surgical treatment of fifth metatarsal stress fractures was found to be associated with higher body mass index (BMI) and with radiological parameters (IMA4-5 on AP radiographs, MT5-LD on oblique radiographs) associated with protrusion of the fifth metatarsal head. The study indicates that patients with a protruding fifth metatarsal head and a high BMI should approach rehabilitation with care before considering a return to previous sporting activity levels. Level of Evidence: Level III, retrospective comparative series. Keywords: fifth metatarsal, stress fracture, refracture, causative factor
Introduction
1
Fractures located at the metaphyseal-diaphyseal junction at the base of the fifth metatarsal were first described by Sir Robert Jones8 in 1902, who reported on 4 fifth-metatarsal fractures, including a personal fracture that occurred while dancing. Much has since been written about fractures of the base of the fifth metatarsal, and considerable controversy remains regarding diagnosis, classification, pathomechanics,
KT Lee’s Orthopedic Hospital, Seoul, Republic of Korea Ajou University Hospital, Gyeonggi-do, Republic of Korea 3 Seoul Medical Center, Seoul, Republic of Korea 4 Eulji Medical Center, Eulji University School of Medicine, Foot and Ankle Clinic, Seoul, Republic of Korea 2
Corresponding Author: Young-uk Park, MD, PhD, Ajou University Hospital, 164 World Cup Road, Yeongtong-gu, Gyeonggi-do, 443-380, Republic of Korea. Email: [email protected]
Downloaded from fai.sagepub.com at UNIV MASSACHUSETTS BOSTON on September 1, 2014
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Foot & Ankle International 34(12)
Figure 1. Torg classification of fifth metatarsal stress fracture. Type I is defined as an acute fracture on a chronic process with evidence of prior periosteal reaction and absence of medullary sclerosis. Type II shows a similar process; however, medullary sclerosis and narrowing consistent with delayed union are present. Type III fractures are those with obliteration of the medullary canal and are classified as nonunions.
the incidences and potential causes of delayed unions and nonunions, and the optimal method of treatment. The treatment of fractures of the proximal fifth metatarsal diaphysis (Jones fractures) can be challenging and at times can result in significant disability, especially in elite athletes. Dameron2 was the first to suggest that the treatment of Jones fractures in athletes should receive additional considerations, and subsequently others have reported high rates of refracture and delayed union after treatment in athletes.1,3,10,13,21 It appears to be widely agreed that proximal fractures of the metaphyseal/diaphyseal region of the fifth metatarsal (excluding avulsion fractures) are prone to delayed union or even nonunion.2,3,10,14,20 Complications including delayed union and nonunion and extensive non-weight-bearing time led some researchers to devise a classification system that can be used to determine surgical technique and predict outcome for fifth metatarsal Jones fractures. Torg et al20 classified fractures involving the proximal part of the diaphysis of the fifth metatarsal into 3 subtypes. Type I fractures are acute fractures visualized radiographically as a narrow fracture line and the absence of intramedullary sclerosis. Type II fractures show delayed union, widening of the fracture line, and evidence of intramedullary sclerosis on plain radiographs. Type III fractures exhibit nonunion with widening of the fracture line and complete medullary canal obliteration by sclerotic bone (Figure 1). Lee et al12 classified fractures involving the proximal part of the diaphysis of the fifth metatarsal into 2 groups according to fracture morphology and the presence or absence of a plantar gap of greater than 1 mm. Group A (the complete fracture group) had a fracture line clearly extending to the medial and dorsal cortex) and Group B
(incomplete fracture group) had a fracture line limited to the plantar lateral area of the fifth metatarsal bone without progression to the medial and dorsal cortex. Patients in group A were subdivided into 2 groups by fracture morphology, that is, group A1 (acute fracture) or group A2 (acute on chronic fracture). Patients in group B were also subdivided into 2 groups by plantar gap, that is, group B1 (incomplete fracture and a plantar gap of less than 1 mm) or group B2 (incomplete fracture and a plantar gap of 1 mm or larger) (Figure 2). According to some studies, nonunion seems to be correlated with fracture severity,13 and thus classification systems have prognostic value in terms of predicting the risk of nonunion. However, refracture occurs sometimes following fractures of low grade, even a long time after the achievement of union. Furthermore, some researchers have stated that fifth metatarsal stress fracture is correlated with cavus deformity.11 Raikin et al17 reported that varus hindfoot alignment might be a predisposing factor to development of fracture or refracture after fixation. No comparison study has been performed on the cause of refracture after surgical treatment of fifth metatarsal stress fracture. Accordingly, the present study was undertaken to identify causative structural abnormalities and other factors for refracture of fifth metatarsal stress fractures.
Methods This retrospective study was approved by our institutional review board. Between March 2002 and June 2011, 168 cases of fifth metatarsal stress fracture (163 patients) were treated using modified tension band wiring. Mean length of follow up was 23.6 months (range, 10-112 months). This
Downloaded from fai.sagepub.com at UNIV MASSACHUSETTS BOSTON on September 1, 2014
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Lee et al
Figure 2. Lee et al classification of fifth metatarsal stress fracture. Group A (complete fracture group, fracture line clearly seen extending to the medial and dorsal cortex) and Group B (incomplete fracture group, fracture line limited to plantar lateral area of the fifth metatarsal bone, without progression to the medial and dorsal cortex). Group A was subdivided into 2 groups according to fracture morphology: group A1 (acute fracture) and group A2 (acute on chronic fracture). Group B was subdivided into 2 groups according to the plantar gap: group B1 (incomplete fracture, plantar gap less than 1 mm) and group B2 (incomplete fracture, plantar gap 1 mm or larger).
consecutive series of patients included 159 men and 4 women of mean age 19.6 years (range, 13-33 years) at surgery. Of these, 11 experienced nonunion and 18 refracture. Among the 163 patients, 80 were right sided, 78 were left sided, and 5 were bilateral. One hundred fifty-nine patients were soccer players, 1 was a hockey player, 1 was a rugby player, and 2 were basketball players. All patients were treated using modified tension band wiring, and inlay bone grafting was used in cases of Torg type III fractures. Patients were then immobilized in a short leg splint. Postoperatively, the patients were instructed not to bear weight and to use a short leg cast for 6 weeks. Then, they were placed into a walking boot with progressive weight-bearing as tolerated. All athletes were allowed to return to unrestricted activity when they were clinically asymptomatic and when they showed progress in bone union, as indicated on radiographs followed by computed tomography (CT) scans. For patients with signs of progressive union, CT scan was routinely repeated about 2 months after the operation. Treatment results were evaluated by retrospectively reviewing hospital records and radiographs. Bone union was considered to have been achieved when the cortical continuity of the plantar side of the fracture gap (plantar gap) was reestablished with callus on a CT scan. There were 11 cases of nonunion, which was defined as the absence of visible progressive signs of healing for 3 months regardless of symptoms. Nine nonunion cases were Torg type II and 2 were Torg type III (Figure 1). According to the classification by Lee et al (Figure 2), there was 1
complete fracture (A1, compete and acute) and 10 incomplete fractures (B2, incomplete, plantar gap larger than 1 mm). In nonunion cases, autogenous bone grafting was performed after hardware removal. A rectangular section of bone centered over the fracture was removed with a sharp osteotome. An autogenous corticocancellous bone graft was then removed from the anterior process of the calcaneus through a second incision; care was taken to contour the graft so that the cortical portion of the graft accurately fit into the rectangular cortical defect. There were 18 cases of refracture: 6 Torg type I, 7 type II, and 5 type III. According to the classification by Lee et al, there were 4 type A1, 1 type A2, 4 type B1, and 9 type B2. Patients were allocated to a refracture group (n = 18) or a union group (n = 139), after we excluded cases of nonunion. These 2 groups were compared with respect to clinical features, which included age, weight, body mass index (BMI), classification, union time, and reinjury history. Each case was classified according to the Torg classification and the Lee et al classification. Fourth-to-fifth intermetatarsal (IMA4-5) angle and fifth metatarsal lateral deviation (MT5-LD) angle were measured on standing anteroposterior (AP) radiographs (Figure 3). Talo–first metatarsal (T-MT1) angle, talocalcaneal (TC) angle, and calcaneal pitch (CP) angle were measured on standing lateral views, and MT5-LD angle was measured on 30-degree medial oblique views (Figure 3). Radiographic features were compared to evaluate the effects of structural abnormalities such as cavovarus deformity.
Downloaded from fai.sagepub.com at UNIV MASSACHUSETTS BOSTON on September 1, 2014
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Figure 3. Fourth-to-fifth intermetatarsal angle: the angle subtended by the intersecting axes of the fourth and fifth metatarsals. Fifth metatarsal lateral deviation: the angle created by a line bisecting the midpoint of the articular surface of the head and the neck of the fifth metatarsal and line adjacent and parallel to the medial surface of the proximal metatarsal.
Surgical Technique Two cortical screws (diameter, 2.7 mm) were placed on the proximal and distal fragment, 1 cm away from the fracture site more on the plantar side, since it is the tension side. The screw hole was deepened using a countersink to avoid irritation from a prominent screw head. Using the reduction clamp on the screws, the fracture was compressed and a wire loop was tightened around the screws in a figure-ofeight fashion. Then, 2 screws were retightened.
Statistical Analysis Statistical significance was accepted for P values of
