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Predictors of Peroneal Pathology in Broström−Gould Ankle Ligament Reconstruction for Lateral Ankle Instability M. Tyrrell Burrus, Brian C. Werner, Michael M. Hadeed, Joseph B. Walker, Venkat Perumal and Joseph S. Park Foot Ankle Int published online 20 October 2014 DOI: 10.1177/1071100714556759 The online version of this article can be found at: http://fai.sagepub.com/content/early/2014/10/20/1071100714556759
Published by: http://www.sagepublications.com
On behalf of:
American Orthopaedic Foot & Ankle Society
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556759
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FAIXXX10.1177/1071100714556759Foot & Ankle InternationalBurrus et al
(Original) Clinical Research Article
Predictors of Peroneal Pathology in Broström–Gould Ankle Ligament Reconstruction for Lateral Ankle Instability
Foot & Ankle International® 1–9 © The Author(s) 2014 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/1071100714556759 fai.sagepub.com
M. Tyrrell Burrus, MD1, Brian C. Werner, MD1, Michael M. Hadeed, BS1, Joseph B. Walker, BS1, Venkat Perumal, MD1, and Joseph S. Park, MD2
Abstract Background: Chronic ankle instability has a well-known association with intra- and extraarticular ankle pathologies, including peroneal tendonitis and subluxation. Patients with peroneal pathology are at risk for failure of conservative treatment for their ankle instability, thus identifying these patients is important and helps to guide management. There has been no literature evaluating patients with chronic ankle instability which associated ankle pathologies for patient characteristics predictive of peroneal pathology. Methods: A retrospective chart review was performed on all patients (N = 136) who underwent a Broström–Gould ankle ligament reconstruction at a single institution from 2010 to 2014. Preoperative clinical examinations and MRIs as well as operative procedures were documented. Patients with and without peroneal pathology were divided into 2 cohorts, and their preoperative characteristics underwent a univariate analysis with P < .05 defined as showing a significant difference. Results: Of patients undergoing lateral ankle ligament reconstruction, 53.3% required operative intervention for symptomatic peroneal tendon pathology. Female gender was the only significant predictor of peroneal pathology (P = .008). The presence of an osteochondral lesion of the talus (OLT) was a significant negative predictor of peroneal pathology (P < .001). The remainder of the variables (age, BMI, duration of symptoms, tobacco, traumatic etiology, worker’s compensation, global hyperlaxity, contralateral ankle instability, sport participation, ankle tilt, and deltoid tear) did not show a significant difference between cohorts. Conclusion: In patients who underwent Broström–Gould ankle ligament reconstruction for chronic lateral ankle instability, female gender was significantly associated with concomitant peroneal tendon pathology. Conversely, preoperative MRI findings of an OLT showed a significant negative association with peroneal pathology. All of the other variables did not show a positive or negative association. Level of Evidence: Level III, retrospective comparative case series. Keywords: ankle instability, peroneal tendon, subluxation, osteochondral lesion of the talus, female
An estimated 30 000 ankle sprains are diagnosed daily in US emergency rooms.6 Of those patients who progress to chronic lateral ankle instability, nearly 20% will fail conservative management, assuring the continued rise in incidence of lateral ankle ligament reconstruction in the United States.3,5,13 In addition to being associated with intra-articular pathology, chronic lateral ankle instability has a recognized correlation with peroneal tendon pathology and instability and has even been named “lateral ankle triad” with lateral ankle instability, ankle synovitis, and peroneal tendon tears.1,7,8,16,17,28 Peroneal subluxations occur in 0.3% to 0.5% of acute traumatic events to the ankle, and an estimated 44% to 77% of patients with chronic ankle instability will suffer from some form of peroneal tendon pathology.1,11,12,15
Various explanations have been presented to justify the existence of concomitant ankle instability and peroneal pathology, and, in many patients, it is likely a combination of these concepts. In acute inversion and dorsiflexion ankle injuries, the peroneal muscles may contract with enough 1
Department of Orthopaedic Surgery, University of Virginia Health System, Charlottesville, VA, USA 2 Foot and Ankle Service, Department of Orthopaedic Surgery, University of Virginia Health System, Charlottesville, VA, USA Corresponding Author: Joseph S. Park, MD, Foot and Ankle Service, Department of Orthopaedic Surgery, University of Virginia Health System, PO Box 800159 HSC, Charlottesville, VA 22908, USA. Email: [email protected]
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Figure 1. Intraoperative image of longitudinal tears of the peroneus brevis in a 19-year-old female volleyball player with 2 years of ankle instability symptoms. After undergoing a Broström–Gould as well as peroneal tenolysis and tendon repair, fibular groove deepening, and retinacular repair, she returned to collegiate competition the following season.
force to disrupt the peroneal retinaculum from the fibular surface.31 For chronic instability, a popular theory based off of human and cadaveric research is that as the lateral ankle ligaments become incompetent so the peroneal tendons serve as important secondary dynamic stabilizers.7,17,22,38 Unfortunately, they are unable to provide sufficient stability, and, through recurrent instability events, the peroneal retinaculum gradually attenuates, which allows the tendon to subluxate and tear on the sharp edge of the tip of the posterolateral fibula (Figure 1).8 In addition, evidence exists that ankle instability results in and may be aggravated by peroneal muscle deactivation or weakness, thus exacerbating the ankle instability resulting in gradual attenuation of the peroneal retinaculum.14,25,28 Although no evidence exists that a space-occupying, low-lying peroneus brevis muscle belly initiates ankle instability, it is a known risk factor for peroneal instability and likely predisposes patients with ankle instability to develop peroneal pathology, as a lower threshold exists for retinacular laxity.34 Various treatment options exist for peroneal pathology. Some procedures stabilize the tendon in the fibular groove and thus address the instability directly, including fibular groove deepening, peroneal retinacular repair (Figure 2), and excision of a low-lying peroneal brevis muscle belly. Other procedures address the consequences of peroneal instability, by performing a tendon repair, tendon tubularization (Figure 3), or tendon reconstruction. While the operative focus of ankle instability is the management of the attenuated and/or torn lateral ankle ligaments, peroneal pathology including tears, subluxation, and frank dislocation has received increased attention over past years. Despite this expanded focus, there lacks a
Figure 2. Intraoperative image of a peroneal retinacular repair using drill holes and nonabsorbable sutures through the posterolateral fibula.
Figure 3. Intraoperative image of a peroneal tubularization procedure using a running monofilament suture.
satisfactory characterization of patients at risk for peroneal pathology. As the incidence of ankle sprains and resultant chronic ankle instability continues to increase, identifying patients at risk for peroneal pathology is paramount, as it is a known risk factor for failure of conservative treatment and for continued ankle symptoms following lateral ligament reconstruction.8,9,21 Recognizing and treating at-risk patients early could expedite their return to sport or work, reduce the need for secondary procedures addressing the peroneal tendons, and could decrease the overall economic burden of ankle instability. The purpose of this study was to describe which characteristics in a patient with chronic lateral ankle instability increase the risk for peroneal pathology. Our null hypothesis was that duration of symptoms, increased body mass index, the presence of an osteochondral lesion of the talus (OLT), and generalized hyperlaxity would be significant predictors.
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Burrus et al
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Methods
deepening was performed when, after performing tenolysis and/or low-lying muscle belly excision, the groove was noted to be insufficiently deep to contain the peroneal tendons through ankle range of motion. A univariate analysis using the Student’s t test and chisquare calculation was performed using SPSS (SPSS, version 22, Chicago, IL) with clinical significance defined as P < .05. Post hoc power analyses were completed for duration of symptoms, BMI, the presence of an OLT, and generalized hyperlaxity.
After institutional review board approval, a retrospective chart review was performed on 186 patients who underwent a lateral ankle ligament reconstruction from 2010 to 2014 by 2 foot and ankle specialists at a single institution. All patients had failed an appropriate period of nonoperative management consisting of rest for aggravating activities, bracing, and physical therapy focusing on peroneal strengthening and proprioceptive exercises. Although there was no strict duration of required conservative management, most patients underwent at least 6 weeks of the above management. Certain patient populations, such as those with unstable OLTs or advanced peroneal tendon pathology, were not required to undergo 6 weeks of conservative treatment. All other patients completed a physical therapy program focusing on ankle proprioception, peroneal tendon strengthening, and various anti-inflammatory modalities. The inclusion criteria were (1) patients who underwent a primary Broström–Gould lateral ankle ligament reconstruction for chronic ankle instability and (2) age 15 to 65 years old. Patients were excluded if (1) a lateral ankle ligament reconstruction technique other than a Broström–Gould was performed or (2) the patient had undergone prior foot or ankle surgery of any type. Of the 186 patients who met inclusion criteria, 12 patients were excluded for undergoing an allograft reconstruction technique and 38 were excluded for having undergone prior foot or ankle surgery, resulting in a final study population of 136 patients. All magnetic resonance imaging (MRI) studies were reviewed by 1 of 4 fellowship-trained musculoskeletal radiologists as well as the attending surgeon. MRIs were reviewed for OLTs, peroneus brevis and longus tendinopathy, tears, dislocation, and subluxation, and tendonitis. Variables examined as potential predictors of peroneal pathology included age, body mass index (BMI), duration of symptoms, gender, presence of an OLT, deltoid ligament injury, smoking, diabetes mellitus, contralateral ankle instability, generalized hyperlaxity, current athletic participation, presence of radiographic ankle tilt, and related workman’s compensation claim. Peroneal pathology was defined by having undergone 1 or more of the following operative procedures: fibular groove deepening, peroneal retinacular repair, excision of a low-lying peroneal brevis muscle belly, peroneal tenolysis, or peroneal tendon tubularization or repair. Exploration of the peroneal tendons with a tenolysis was indicated based on clinical examination focusing on tenderness along the tendons (especially at the tip of the fibula), weakness and pain with resisted eversion, and subluxation on dorsiflexion and eversion. The decision to do retinacular repair was made based on preoperative evidence of subluxation as well as the ability to subluxate the tendon intraoperatively with passive ankle dorsiflexion and eversion. Fibular groove
Results A total of 136 patients were included in the study, and the summary of their preoperative characteristics are seen in Table 1 and Table 2. Average age of the entire cohort was 35.1 ± 14.6 years. The average BMI was 29.4 ± 6.8 kg/m2. In all, 72 patients (53.3%) were female, 10 patients (7.3%) were smokers, 6 patients (4.4%) were worker’s compensation, 50 patients (36.5%) participated in sports, and 8 patients (5.8%) had global laxity diagnosed preoperatively. The initial mechanism of injury was reported as traumatic in 113 patients (83.2%), with an average duration of symptoms of 36.9 (range, 2-360) months prior to operative intervention. On preoperative examination, 6 patients (4.4%) had 1+ rotational ankle instability, 82 patients (61.3%) had 2+ rotational ankle instability, and 48 patients (32.8.0%) had 3+ rotational ankle instability. A total of 77 patients (56.2%) had a positive ankle anterior drawer on examination, 63 patients (46.0%) had tenderness to palpation over the peroneal tendons, 54 patients (39.4%) had subluxatable peroneal tendons, and 3 patients (2.2%) had dislocated peroneal tendons. Preoperative MRI demonstrated 86 patients (66.2%) with an ATFL tear, 67 patients (51.5%) with a CFL tear and 1 patient (0.8%) with a PTFL tear; 49 patients (37.7%) had peroneal tendinopathy on MRI, 18 patients (13.8%) had peroneal tearing, 2 patients (1.5%) had peroneal subluxation, 8 patients had peroneal retinacular tears (6.2%), 16 patients (12.3%) had deltoid ligament tears, 24 patients (18.5%) had medial OLTs, and 14 patients (10.8%) had lateral OLTs on MRI. All patients underwent Broström–Gould lateral ligament reconstruction procedure. A total of 129 patients (94.2%) underwent a concomitant ankle arthroscopy, 44 patients (32.1%) underwent microfracture of a cartilage defect, 72 patients (52.6%) underwent concomitant peroneal tenolysis, 63 patients (46.0%) underwent a low-lying peroneal muscle belly excision, 13 patients (9.5%) underwent peroneal tendon repair, 8 patients (5.8%) underwent peroneal tendon tubularization, 40 patients (29.2%) underwent peroneal groove deepening, and 58 patients (42.3%) underwent peroneal retinacular repair.
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Table 1. Preoperative Patient Characteristics of Both Cohorts. Preoperative Patient Characteristics
n (%)
Number (N) Age (years; mean ± SD) Female BMI (kg/m2; mean ± SD) Smoking Worker’s compensation Sport participation Global hyperlaxity Traumatic ankle injury Duration of symptoms (months; mean ± SD) Ankle tilt on radiographs Clinical examination 1+ rotational instability 2+ rotational instability 3+ rotational instability Positive anterior drawer Tenderness over the peroneal tendons Subluxating peroneal tendons Dislocated peroneal tendons Preoperative MRI ATFL tear CFL tear PTFL tear Peroneal tendinopathy Peroneal tendon tear Peroneal tendon subluxation Peroneal retinacular tear Deltoid tear Medial OLT Lateral OLT
136 (100) 35.1 ± 14.6 72 (53.3) 29.4 ± 6.8 10 (7.3) 6 (4.4) 50 (36.5) 8 (5.8%) 113 (83.2) 36.9 ± 70.3 4 (3.0) 6 (4.4) 82 (61.3) 48 (32.8) 77 (56.2) 63 (46.0) 54 (39.4) 3 (2.2) 86 (66.2) 67 (51.5) 1 (0.8) 49 (37.7) 18 (13.8) 2 (1.5) 8 (6.2) 16 (12.3) 24 (18.5) 14 (10.8)
ATFL, anterior talofibular ligament; BMI, body mass index; CFL, calcaneofibular ligament; kg, kilogram; m, meter; OLT, osteochondral lesion of the talus; PTFL, posterior talofibular ligament.
The results of univariate analysis comparing patients with and without peroneal tendon intervention at the time of lateral ligament reconstruction are presented in Table 3 and Table 4. Patients with peroneal pathology were more frequently female (65% vs 42%, P = .008). Overall OLT (P < .001), medial OLT (P = .004), and lateral OLT (P = .018) were all more commonly present in patients without operative peroneal pathology. For the remainder of the variables, with the numbers available, no significant difference could be detected. Average age in patients without peroneal pathology was 33.6 years compared to 37.0 years in patients with peroneal pathology. The average BMI of the patients without peroneal pathology was 28.9 compared to 29.7. Additional variables that did not show significance were tobacco use, traumatic etiology of symptoms, worker’s compensation status, duration of symptoms, global laxity, participation in sports, preoperative presence of ankle tilt on X-ray, or deltoid tear on preoperative MRI.
Table 2. Frequency of Concomitant Procedures Including Patients From Both Cohorts. Procedure Lateral ankle ligament reconstruction Ankle arthroscopy Peroneal tenolysis Peroneal retinacular repair Low-lying peroneus brevis muscle excision Talus microfracture Peroneal groove deepening Peroneal tendon repair Peroneal tendon tubularization
n (%) 136 (100) 129 (94.2) 72 (52.6) 58 (42.3) 63 (46.0) 44 (32.1) 40 (29.2) 13 (9.5) 8 (5.8)
Discussion Vigilance for peroneal pathology in patients with ankle instability is important, as 50% of patients with concomitant peroneal subluxation will fail conservative treatment of their chronic lateral ankle instability.9 While the incidence of these pathologies coexisting is estimated at 17% to 77%, it is felt that most studies underestimate its prevalence.1,2,15 In addition, many surgeons believe that, while up to 80% of patients with isolated ankle instability will improve with nonoperative management, peroneal pathology more often requires operative intervention.1-3,5,13,19,27,31 Fortunately, studies have shown excellent outcomes following peroneal stabilization and debridement/repair procedures.1,19,26,31,39 Female gender was the only significant positive predictor of peroneal pathology (P = .008). Of these patients, 64.9% were females, compared to 53.3% of the entire study population. To our knowledge, this relationship has never been reported. Most publications on peroneal tendon pathology either do not comment on gender or are not focused on ankle instability patients; other than a single study showing a 14.3% incidence of females with peroneal pathology and ankle instability, this association is not well documented in this population.39 When reviewing peroneal pathology for any reason (including when it is seen in isolation), there is tremendous variation with some studies very male dominant and some studies female dominant. Potential theories for this relationship included hormone related alterations in laxity and deficits in proprioception and muscle training, much like that researched as a potential risk factor for female anterior cruciate ligament (ACL) injuries.30,37 Peroneal dysfunction or weakness has been shown to be associated with a proprioceptive defect, but it is not known if tendinopathy causes or results in this defect.7 The female relationship with peroneal pathology has not been well explored in the literature. Further analysis of the data attempted to see if there were any significant associations between other variables and females (compared to males), which could lead to this finding of a positive predictor of peroneal pathology. Females
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Burrus et al Table 3. Comparison of Preoperative Patient Characteristics and Radiographic Parameters Between Cohorts Using Chi-Square Analysis.
Preoperative Patient Characteristic Female Smoking Traumatic etiology Worker’s compensation Contralateral ankle instability Global hyperlaxity Sport participation Ankle tilt on radiographs Deltoid tear Medial OLT Lateral OLT Medial or Lateral OLT
Peroneal Pathology
No Peroneal Pathology
n
(%)
n
(%)
P Value
74 48 10 60 2 15 5 23 5 10 7 4 11
54.4 64.9 13.5 81.1 2.7 20.3 6.8 31.1 6.8 13.5 9.5 5.4 14.9
62 27 3 53 4 19 4 24 2 7 17 11 28
45.6 43.5 4.8 85.5 6.5 30.6 6.5 38.7 3.2 11.3 27.4 17.7 45.2
n/a .008 .085 .488 .292 .169 .937 .448 .350 .754 .004 .018
Predictors of Peroneal Pathology in Broström−Gould Ankle Ligament Reconstruction for Lateral Ankle Instability M. Tyrrell Burrus, Brian C. Werner, Michael M. Hadeed, Joseph B. Walker, Venkat Perumal and Joseph S. Park Foot Ankle Int published online 20 October 2014 DOI: 10.1177/1071100714556759 The online version of this article can be found at: http://fai.sagepub.com/content/early/2014/10/20/1071100714556759
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
>> OnlineFirst Version of Record - Oct 20, 2014 What is This?
Downloaded from fai.sagepub.com at TEXAS SOUTHERN UNIVERSITY on November 19, 2014
556759
research-article2014
FAIXXX10.1177/1071100714556759Foot & Ankle InternationalBurrus et al
(Original) Clinical Research Article
Predictors of Peroneal Pathology in Broström–Gould Ankle Ligament Reconstruction for Lateral Ankle Instability
Foot & Ankle International® 1–9 © The Author(s) 2014 Reprints and permissions: sagepub.com/journalsPermissions.nav DOI: 10.1177/1071100714556759 fai.sagepub.com
M. Tyrrell Burrus, MD1, Brian C. Werner, MD1, Michael M. Hadeed, BS1, Joseph B. Walker, BS1, Venkat Perumal, MD1, and Joseph S. Park, MD2
Abstract Background: Chronic ankle instability has a well-known association with intra- and extraarticular ankle pathologies, including peroneal tendonitis and subluxation. Patients with peroneal pathology are at risk for failure of conservative treatment for their ankle instability, thus identifying these patients is important and helps to guide management. There has been no literature evaluating patients with chronic ankle instability which associated ankle pathologies for patient characteristics predictive of peroneal pathology. Methods: A retrospective chart review was performed on all patients (N = 136) who underwent a Broström–Gould ankle ligament reconstruction at a single institution from 2010 to 2014. Preoperative clinical examinations and MRIs as well as operative procedures were documented. Patients with and without peroneal pathology were divided into 2 cohorts, and their preoperative characteristics underwent a univariate analysis with P < .05 defined as showing a significant difference. Results: Of patients undergoing lateral ankle ligament reconstruction, 53.3% required operative intervention for symptomatic peroneal tendon pathology. Female gender was the only significant predictor of peroneal pathology (P = .008). The presence of an osteochondral lesion of the talus (OLT) was a significant negative predictor of peroneal pathology (P < .001). The remainder of the variables (age, BMI, duration of symptoms, tobacco, traumatic etiology, worker’s compensation, global hyperlaxity, contralateral ankle instability, sport participation, ankle tilt, and deltoid tear) did not show a significant difference between cohorts. Conclusion: In patients who underwent Broström–Gould ankle ligament reconstruction for chronic lateral ankle instability, female gender was significantly associated with concomitant peroneal tendon pathology. Conversely, preoperative MRI findings of an OLT showed a significant negative association with peroneal pathology. All of the other variables did not show a positive or negative association. Level of Evidence: Level III, retrospective comparative case series. Keywords: ankle instability, peroneal tendon, subluxation, osteochondral lesion of the talus, female
An estimated 30 000 ankle sprains are diagnosed daily in US emergency rooms.6 Of those patients who progress to chronic lateral ankle instability, nearly 20% will fail conservative management, assuring the continued rise in incidence of lateral ankle ligament reconstruction in the United States.3,5,13 In addition to being associated with intra-articular pathology, chronic lateral ankle instability has a recognized correlation with peroneal tendon pathology and instability and has even been named “lateral ankle triad” with lateral ankle instability, ankle synovitis, and peroneal tendon tears.1,7,8,16,17,28 Peroneal subluxations occur in 0.3% to 0.5% of acute traumatic events to the ankle, and an estimated 44% to 77% of patients with chronic ankle instability will suffer from some form of peroneal tendon pathology.1,11,12,15
Various explanations have been presented to justify the existence of concomitant ankle instability and peroneal pathology, and, in many patients, it is likely a combination of these concepts. In acute inversion and dorsiflexion ankle injuries, the peroneal muscles may contract with enough 1
Department of Orthopaedic Surgery, University of Virginia Health System, Charlottesville, VA, USA 2 Foot and Ankle Service, Department of Orthopaedic Surgery, University of Virginia Health System, Charlottesville, VA, USA Corresponding Author: Joseph S. Park, MD, Foot and Ankle Service, Department of Orthopaedic Surgery, University of Virginia Health System, PO Box 800159 HSC, Charlottesville, VA 22908, USA. Email: [email protected]
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Figure 1. Intraoperative image of longitudinal tears of the peroneus brevis in a 19-year-old female volleyball player with 2 years of ankle instability symptoms. After undergoing a Broström–Gould as well as peroneal tenolysis and tendon repair, fibular groove deepening, and retinacular repair, she returned to collegiate competition the following season.
force to disrupt the peroneal retinaculum from the fibular surface.31 For chronic instability, a popular theory based off of human and cadaveric research is that as the lateral ankle ligaments become incompetent so the peroneal tendons serve as important secondary dynamic stabilizers.7,17,22,38 Unfortunately, they are unable to provide sufficient stability, and, through recurrent instability events, the peroneal retinaculum gradually attenuates, which allows the tendon to subluxate and tear on the sharp edge of the tip of the posterolateral fibula (Figure 1).8 In addition, evidence exists that ankle instability results in and may be aggravated by peroneal muscle deactivation or weakness, thus exacerbating the ankle instability resulting in gradual attenuation of the peroneal retinaculum.14,25,28 Although no evidence exists that a space-occupying, low-lying peroneus brevis muscle belly initiates ankle instability, it is a known risk factor for peroneal instability and likely predisposes patients with ankle instability to develop peroneal pathology, as a lower threshold exists for retinacular laxity.34 Various treatment options exist for peroneal pathology. Some procedures stabilize the tendon in the fibular groove and thus address the instability directly, including fibular groove deepening, peroneal retinacular repair (Figure 2), and excision of a low-lying peroneal brevis muscle belly. Other procedures address the consequences of peroneal instability, by performing a tendon repair, tendon tubularization (Figure 3), or tendon reconstruction. While the operative focus of ankle instability is the management of the attenuated and/or torn lateral ankle ligaments, peroneal pathology including tears, subluxation, and frank dislocation has received increased attention over past years. Despite this expanded focus, there lacks a
Figure 2. Intraoperative image of a peroneal retinacular repair using drill holes and nonabsorbable sutures through the posterolateral fibula.
Figure 3. Intraoperative image of a peroneal tubularization procedure using a running monofilament suture.
satisfactory characterization of patients at risk for peroneal pathology. As the incidence of ankle sprains and resultant chronic ankle instability continues to increase, identifying patients at risk for peroneal pathology is paramount, as it is a known risk factor for failure of conservative treatment and for continued ankle symptoms following lateral ligament reconstruction.8,9,21 Recognizing and treating at-risk patients early could expedite their return to sport or work, reduce the need for secondary procedures addressing the peroneal tendons, and could decrease the overall economic burden of ankle instability. The purpose of this study was to describe which characteristics in a patient with chronic lateral ankle instability increase the risk for peroneal pathology. Our null hypothesis was that duration of symptoms, increased body mass index, the presence of an osteochondral lesion of the talus (OLT), and generalized hyperlaxity would be significant predictors.
Downloaded from fai.sagepub.com at TEXAS SOUTHERN UNIVERSITY on November 19, 2014
Burrus et al
3
Methods
deepening was performed when, after performing tenolysis and/or low-lying muscle belly excision, the groove was noted to be insufficiently deep to contain the peroneal tendons through ankle range of motion. A univariate analysis using the Student’s t test and chisquare calculation was performed using SPSS (SPSS, version 22, Chicago, IL) with clinical significance defined as P < .05. Post hoc power analyses were completed for duration of symptoms, BMI, the presence of an OLT, and generalized hyperlaxity.
After institutional review board approval, a retrospective chart review was performed on 186 patients who underwent a lateral ankle ligament reconstruction from 2010 to 2014 by 2 foot and ankle specialists at a single institution. All patients had failed an appropriate period of nonoperative management consisting of rest for aggravating activities, bracing, and physical therapy focusing on peroneal strengthening and proprioceptive exercises. Although there was no strict duration of required conservative management, most patients underwent at least 6 weeks of the above management. Certain patient populations, such as those with unstable OLTs or advanced peroneal tendon pathology, were not required to undergo 6 weeks of conservative treatment. All other patients completed a physical therapy program focusing on ankle proprioception, peroneal tendon strengthening, and various anti-inflammatory modalities. The inclusion criteria were (1) patients who underwent a primary Broström–Gould lateral ankle ligament reconstruction for chronic ankle instability and (2) age 15 to 65 years old. Patients were excluded if (1) a lateral ankle ligament reconstruction technique other than a Broström–Gould was performed or (2) the patient had undergone prior foot or ankle surgery of any type. Of the 186 patients who met inclusion criteria, 12 patients were excluded for undergoing an allograft reconstruction technique and 38 were excluded for having undergone prior foot or ankle surgery, resulting in a final study population of 136 patients. All magnetic resonance imaging (MRI) studies were reviewed by 1 of 4 fellowship-trained musculoskeletal radiologists as well as the attending surgeon. MRIs were reviewed for OLTs, peroneus brevis and longus tendinopathy, tears, dislocation, and subluxation, and tendonitis. Variables examined as potential predictors of peroneal pathology included age, body mass index (BMI), duration of symptoms, gender, presence of an OLT, deltoid ligament injury, smoking, diabetes mellitus, contralateral ankle instability, generalized hyperlaxity, current athletic participation, presence of radiographic ankle tilt, and related workman’s compensation claim. Peroneal pathology was defined by having undergone 1 or more of the following operative procedures: fibular groove deepening, peroneal retinacular repair, excision of a low-lying peroneal brevis muscle belly, peroneal tenolysis, or peroneal tendon tubularization or repair. Exploration of the peroneal tendons with a tenolysis was indicated based on clinical examination focusing on tenderness along the tendons (especially at the tip of the fibula), weakness and pain with resisted eversion, and subluxation on dorsiflexion and eversion. The decision to do retinacular repair was made based on preoperative evidence of subluxation as well as the ability to subluxate the tendon intraoperatively with passive ankle dorsiflexion and eversion. Fibular groove
Results A total of 136 patients were included in the study, and the summary of their preoperative characteristics are seen in Table 1 and Table 2. Average age of the entire cohort was 35.1 ± 14.6 years. The average BMI was 29.4 ± 6.8 kg/m2. In all, 72 patients (53.3%) were female, 10 patients (7.3%) were smokers, 6 patients (4.4%) were worker’s compensation, 50 patients (36.5%) participated in sports, and 8 patients (5.8%) had global laxity diagnosed preoperatively. The initial mechanism of injury was reported as traumatic in 113 patients (83.2%), with an average duration of symptoms of 36.9 (range, 2-360) months prior to operative intervention. On preoperative examination, 6 patients (4.4%) had 1+ rotational ankle instability, 82 patients (61.3%) had 2+ rotational ankle instability, and 48 patients (32.8.0%) had 3+ rotational ankle instability. A total of 77 patients (56.2%) had a positive ankle anterior drawer on examination, 63 patients (46.0%) had tenderness to palpation over the peroneal tendons, 54 patients (39.4%) had subluxatable peroneal tendons, and 3 patients (2.2%) had dislocated peroneal tendons. Preoperative MRI demonstrated 86 patients (66.2%) with an ATFL tear, 67 patients (51.5%) with a CFL tear and 1 patient (0.8%) with a PTFL tear; 49 patients (37.7%) had peroneal tendinopathy on MRI, 18 patients (13.8%) had peroneal tearing, 2 patients (1.5%) had peroneal subluxation, 8 patients had peroneal retinacular tears (6.2%), 16 patients (12.3%) had deltoid ligament tears, 24 patients (18.5%) had medial OLTs, and 14 patients (10.8%) had lateral OLTs on MRI. All patients underwent Broström–Gould lateral ligament reconstruction procedure. A total of 129 patients (94.2%) underwent a concomitant ankle arthroscopy, 44 patients (32.1%) underwent microfracture of a cartilage defect, 72 patients (52.6%) underwent concomitant peroneal tenolysis, 63 patients (46.0%) underwent a low-lying peroneal muscle belly excision, 13 patients (9.5%) underwent peroneal tendon repair, 8 patients (5.8%) underwent peroneal tendon tubularization, 40 patients (29.2%) underwent peroneal groove deepening, and 58 patients (42.3%) underwent peroneal retinacular repair.
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Table 1. Preoperative Patient Characteristics of Both Cohorts. Preoperative Patient Characteristics
n (%)
Number (N) Age (years; mean ± SD) Female BMI (kg/m2; mean ± SD) Smoking Worker’s compensation Sport participation Global hyperlaxity Traumatic ankle injury Duration of symptoms (months; mean ± SD) Ankle tilt on radiographs Clinical examination 1+ rotational instability 2+ rotational instability 3+ rotational instability Positive anterior drawer Tenderness over the peroneal tendons Subluxating peroneal tendons Dislocated peroneal tendons Preoperative MRI ATFL tear CFL tear PTFL tear Peroneal tendinopathy Peroneal tendon tear Peroneal tendon subluxation Peroneal retinacular tear Deltoid tear Medial OLT Lateral OLT
136 (100) 35.1 ± 14.6 72 (53.3) 29.4 ± 6.8 10 (7.3) 6 (4.4) 50 (36.5) 8 (5.8%) 113 (83.2) 36.9 ± 70.3 4 (3.0) 6 (4.4) 82 (61.3) 48 (32.8) 77 (56.2) 63 (46.0) 54 (39.4) 3 (2.2) 86 (66.2) 67 (51.5) 1 (0.8) 49 (37.7) 18 (13.8) 2 (1.5) 8 (6.2) 16 (12.3) 24 (18.5) 14 (10.8)
ATFL, anterior talofibular ligament; BMI, body mass index; CFL, calcaneofibular ligament; kg, kilogram; m, meter; OLT, osteochondral lesion of the talus; PTFL, posterior talofibular ligament.
The results of univariate analysis comparing patients with and without peroneal tendon intervention at the time of lateral ligament reconstruction are presented in Table 3 and Table 4. Patients with peroneal pathology were more frequently female (65% vs 42%, P = .008). Overall OLT (P < .001), medial OLT (P = .004), and lateral OLT (P = .018) were all more commonly present in patients without operative peroneal pathology. For the remainder of the variables, with the numbers available, no significant difference could be detected. Average age in patients without peroneal pathology was 33.6 years compared to 37.0 years in patients with peroneal pathology. The average BMI of the patients without peroneal pathology was 28.9 compared to 29.7. Additional variables that did not show significance were tobacco use, traumatic etiology of symptoms, worker’s compensation status, duration of symptoms, global laxity, participation in sports, preoperative presence of ankle tilt on X-ray, or deltoid tear on preoperative MRI.
Table 2. Frequency of Concomitant Procedures Including Patients From Both Cohorts. Procedure Lateral ankle ligament reconstruction Ankle arthroscopy Peroneal tenolysis Peroneal retinacular repair Low-lying peroneus brevis muscle excision Talus microfracture Peroneal groove deepening Peroneal tendon repair Peroneal tendon tubularization
n (%) 136 (100) 129 (94.2) 72 (52.6) 58 (42.3) 63 (46.0) 44 (32.1) 40 (29.2) 13 (9.5) 8 (5.8)
Discussion Vigilance for peroneal pathology in patients with ankle instability is important, as 50% of patients with concomitant peroneal subluxation will fail conservative treatment of their chronic lateral ankle instability.9 While the incidence of these pathologies coexisting is estimated at 17% to 77%, it is felt that most studies underestimate its prevalence.1,2,15 In addition, many surgeons believe that, while up to 80% of patients with isolated ankle instability will improve with nonoperative management, peroneal pathology more often requires operative intervention.1-3,5,13,19,27,31 Fortunately, studies have shown excellent outcomes following peroneal stabilization and debridement/repair procedures.1,19,26,31,39 Female gender was the only significant positive predictor of peroneal pathology (P = .008). Of these patients, 64.9% were females, compared to 53.3% of the entire study population. To our knowledge, this relationship has never been reported. Most publications on peroneal tendon pathology either do not comment on gender or are not focused on ankle instability patients; other than a single study showing a 14.3% incidence of females with peroneal pathology and ankle instability, this association is not well documented in this population.39 When reviewing peroneal pathology for any reason (including when it is seen in isolation), there is tremendous variation with some studies very male dominant and some studies female dominant. Potential theories for this relationship included hormone related alterations in laxity and deficits in proprioception and muscle training, much like that researched as a potential risk factor for female anterior cruciate ligament (ACL) injuries.30,37 Peroneal dysfunction or weakness has been shown to be associated with a proprioceptive defect, but it is not known if tendinopathy causes or results in this defect.7 The female relationship with peroneal pathology has not been well explored in the literature. Further analysis of the data attempted to see if there were any significant associations between other variables and females (compared to males), which could lead to this finding of a positive predictor of peroneal pathology. Females
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Burrus et al Table 3. Comparison of Preoperative Patient Characteristics and Radiographic Parameters Between Cohorts Using Chi-Square Analysis.
Preoperative Patient Characteristic Female Smoking Traumatic etiology Worker’s compensation Contralateral ankle instability Global hyperlaxity Sport participation Ankle tilt on radiographs Deltoid tear Medial OLT Lateral OLT Medial or Lateral OLT
Peroneal Pathology
No Peroneal Pathology
n
(%)
n
(%)
P Value
74 48 10 60 2 15 5 23 5 10 7 4 11
54.4 64.9 13.5 81.1 2.7 20.3 6.8 31.1 6.8 13.5 9.5 5.4 14.9
62 27 3 53 4 19 4 24 2 7 17 11 28
45.6 43.5 4.8 85.5 6.5 30.6 6.5 38.7 3.2 11.3 27.4 17.7 45.2
n/a .008 .085 .488 .292 .169 .937 .448 .350 .754 .004 .018
