Abstract
Background:
We analyzed clinical and radiologic examination of intra-articular fracture of the proximal phalanx of great toe accompanied by valgus deformity associated with sports activities. Therefore, we assessed valgus deformity of great toe at fracture side and contralateral side by simple radiograph in order to confirm the causal relation of fracture and deformity.
Methods:
A retrospective study was conducted on 23 cases, between January 2000 and August 2014, which showed an intra-articular fracture of proximal phalanx which was diagnosed after visiting our hospital for valgus deformity of great toe as a chief complaint. All patients were involved in sports activities for over 2 years. The site of fracture was the lateral side of the proximal phalanx head in 16 cases and the medial side of the proximal phalanx base in 7 cases. In order to assess the valgus deformity of great toe, hallux valgus angle (HVA) and hallux valgus interphalangeal angle (HVIPA) were measured on the weight-bearing foot radiograph.
Results:
The average HVA of the fracture group on the lateral side of the proximal phalanx head was 10.5° and HVIPA was 17.8°, while the average HVA of the fracture group on the medial side of the proximal phalanx base was 18.1° and HVIPA was 10.7°. Among the 16 cases with a fracture on the lateral side of the head, 13 cases showed hallux valgus interphalangeus (81.3%), while all 7 cases of fracture on the medial side of the base showed hallux valgus (100%).
Conclusion:
Hallux valgus was mostly found on the fracture of the medial side of the proximal phalanx base, while hallux valgus interphalangeus was mostly found on the fracture of the lateral side of the proximal phalanx head.
Introduction
Fracture of tibia, fibula, femur, and metatarsal is often reported on patients who are involved in sports activities on a regular basis, 1 –3 but there have rarely been reports on the fracture of the proximal phalanx of great toe. Most reports on fracture are from Japan, 4 –9 and they have mostly reported fractures on the medial side of proximal phalanx base. 4,5,7,8,9 There has been only one case of report on a fracture that occurred on the lateral side of proximal phalanx head as shown in this study. 6
It is believed that such a fatigue fracture occurs on athletics who engage in Taekwondo, basketball, soccer, and so on. And it mostly occurs in adolescence when the growth plates are not closed or are closed recently.
Most patients with a fracture of proximal phalanx of great toe visited hospital for valgus deformity rather than severe pain (Figure 1). 10 After fracture, valgus deformity progresses gradually, and it can be assumed that hallux valgus and hallux valgus interphalangeus may occur according to the site of fracture.
A clinical photo showing hallux valgus interphalangeus (Case No.12).
Therefore, we analyzed clinical and radiologic examination about intra-articular fracture of the proximal phalanx of great toe associated with sports activities. In addition, anatomical reduction and fixation of intra-articular fracture of great toe was performed to correct valgus deformity and confirm a causal correlation between fracture and deformity.
Materials and methods
This study protocol was approved by the institutional review board of our hospital, and all patients provided written informed consent. A retrospective study was conducted on 23 cases, between January 2000 and August 2014, with complete data of patients who engaged in sports activities regularly and visited our hospital for valgus deformity of great toe as a chief complaint. The inclusion criteria are patients having intra-articular fractures of the proximal phalanx of great toe on initial weight-bearing foot radiograph and those participating in sports activities for more than 2 years.
In all cases, valgus deformity was observed by initial radiograph. And we made a supposition that displacement of intra-articular fracture of great toe caused deformity. To correct deformity, consequently, we conducted anatomical reduction of intra-articular fracture for surgical treatment. Epiphyseal injury of Salter–Harris type III was shown in two of the three cases of proximal phalanx base fracture. During the surgical management of these cases, more delicate procedure was provided to minimize further injury of epiphyseal plate.
Patients’ average age was 10.8 years and all patients were under 20 years (range: 8–18). Additionally, the average bone age was 11.2 years. Except for one case, the growth plates were open in all cases. For all patients, the right side was considered dominant. And 20 of them showed fracture in the right side, and 3 showed fracture in the left side. The study included 19 male and 4 female subjects. The mean follow-up period was 19.1 months.
First and foremost, in order to identify their correlation with the fractures, different sports activities were surveyed using a chart or telephone. In order to evaluate the correlation between the site of fracture and valgus deformity, we analyzed the physical examination, clinical images, and initial radiographs at the time of visit. The site of fracture was identified in the simple radiologic images, while the hallux valgus angle (HVA) and the hallux valgus interphalangeal angle (HVIPA) were measured. The valgus angle was measured using a generally applied method; in detail, the HVA was defined as the angle between the vertical axis of proximal phalanx and the vertical axis of first metatarsal bone, while the HVIPA was defined as the angle between the vertical axis of distal phalanx and the vertical axis of proximal phalanx. We set up diagnostic criteria for hallux valgus and hallux valgus interphalangeus—in the case when each HVA and HVIPA is more than 15°. The authors also measured the valgus angle on the other side for comparison to confirm causal relation of the fracture and deformity.
All fracture patients were treated using open reduction and internal fixation. During management, fracture sites were exposed and the anatomical reduction was performed with the aim of the most correction of deformity. We performed fixation using Kirschner wire (K-wire) when the size of the fracture fragment accompanying displacement is smaller than a diameter of screw. Screws were applied for the fixation of larger sized fracture fragment. After this initial screw fixation, additional K-wire fixations were followed for those with instability.
To compare the results of fixation methods, three group were formed—group 1 (using K-wire: six cases), group 2 (using only cannulated or headless screws: nine cases), and group 3 (using only K-wire and cannulated or headless screw: eight cases). Around 6 months later, we assessed the radiographic and clinical bone union in the outpatients department.
Additionally, valgus deformity was evaluated through postoperation and final follow-up radiologic study to confirm correction of it by the operation. The satisfaction of patients, Visual Analogue Scale (VAS) score, American Orthopedic Foot & Ankle Society (AOFAS) score, and Range of Motion (ROM) of great toe were also assessed for clinical results in the final follow-up.
Results
The sports activities that patients were involved with for over 2 years were 12 cases of Taekwondo (52.2%), 6 cases of soccer (26.1%), 2 cases of basketball (8.7%), 2 cases of running (8.7%), and 1 case of ballet (4.3%), which mainly act as an external force by direct trauma to articular surface of great toe. All of patients were involved with sports activities more than 5 days a week and 2 hours a day.
The site of fracture was on the lateral side of proximal phalanx head in 16 cases (69.5%) and on the medial side of proximal phalanx base in 7 cases (30.5%) by the weight-bearing foot radiograph.
The patient’s average HVA was 12.8° and HVIPA was 15.6°. Average HVA was 10.5° and HVIPA was 17.8° in fracture group of proximal phalanx head. And average HVA was 18.1° and HVIPA was 10.7° in the fracture group of proximal phalanx base.
In the case of diagnostic criteria, valgus angle is more than 15°, hallux valgus interphalangeus was diagnosed for 13 of 16 cases of fracture of the proximal phalanx head (81.3%), and hallux valgus was diagnosed for all 7 cases of fracture of the proximal phalanx base (100%).
Additionally, we measured valgus angle on the other side in order to confirm causal relation of fracture and valgus deformity. The average HVA was 10.8° and HVIPA was 11.5°. Average of HVA of fracture group of the proximal phalanx head was 10.9° and HVIPA was 11.3° (Figure 2). And average HVA of fracture group of the proximal phalanx base was 10.5° and HVIPA was 11.8° (Figure 3). As a result, contralateral side valgus angle was generally less than fracture side valgus angle, and HVA and HVIPA were measured normal range, valgus angle, except for one case (Table 1).
A plain radiograph showing a fracture line involving the lateral head of proximal phalanx of the great toe (Case No.12).
A plain radiograph showing a fracture line involving the medial base of proximal phalanx of the great toe (Case No.9).
Results of overall valgus angle according to the site of fracture.
HVA: hallux valgus angle; HVIPA: hallux valgus interphalangeal angle.
Results of clinical findings.
HVA: hallux valgus angle; HVIPA: hallux valgus interphalangeal angle; K-wire: Kirschner wire.
Only one patient showed hallux valgus deformity on the other side and a fracture on the lateral side of the proximal phalanx head. The patient’s HVA was 22° and HVIPA was 18°.
After around 6 months, we assessed the clinical and radiologic bone union in all patients. Clinical bone union was defined as showing no symptom in spite of the motion of great toe. Additionally, in this study, radiological bone union means the disappearance of fracture gap or the presentation of callus formation in radiographs. As a result, three cases of group 1 showed clinical and radiological bone union, while radiologic nonunion was observed in other three cases with clinical bone union of fracture. Groups 2 and 3 showed clinical and radiological bone union in all cases.
In addition, valgus deformity was evaluated through postoperation and final follow-up radiologic study. Except for one case in the final follow-up, valgus angles were corrected in all cases. Average HVA in postoperative period was 10.9°, and HVIPA was 13.4° in fracture group of proximal phalanx head. And the average HVA in final follow-up was 11.0° and HVIPA was 13.9°. In contrast, the average HVA in postoperative period was 13.4°, and HVIPA was 10.8° in fracture group of proximal phalanx base. And the average HVA in the final follow-up was 14.2° and HVIPA was 10.9° (Figure 4).
A plain radiograph showing postoperative correction of valgus deformity of the great toe. (Case No.12) <A ; postoperative 3 weeks, B ; postoperative 6 months.
Each result of cases is as follows (Table 2). Profound satisfaction of patients and excellent VAS and AOFAS scores were reported. The average VAS score was 0.2, indicating minimized pain. And the average AOFAS score was 91.7. At the final follow-up, significant limitation of ROM was not observed mainly because of early passive range of motion. It was begun only 2 weeks after operation.
Discussion
A fracture of proximal phalanx in patients who engage in regular sports activities was reported only rarely, after it was first reported by Hukko and Orava in 1987. 11 The factors that cause fracture include wrong training and repetitive trauma; 8 fracture can also occur while wearing tight shoes or starting high-intensity training without warm-up. The fractures associated with sports activities generally occur when one often engages in Taekwondo or soccer that acts as an external force with direct trauma to articular surface of great toe.
Unlike the reports in Japan, this study reported more fractures on the lateral side of proximal phalanx head, especially in all patients who engaged in Taekwondo. Jung and Park reported a 23-year-old Taekwondo player’s chronic varus instability caused by the damage of lateral collateral ligament on the interphalangeal joint of great toe. 12 And Lee et al. reported a 16-year-old Taekwondo player’s rupture of the extensor hallucis longus tendon on interphalangeal joint of great toe. 13 It is believed that this part is more often damaged in Korea where Taekwondo is more popular.
Most reports of athletes’ fracture on proximal phalanx of great toe have mentioned it as a fatigue fracture. But this study defined it as an intra-articular fracture because not all patients have engaged in sports activities for longer time period like the cases discussed in other studies and may not have perceived acute fractures. In all cases, the vitamin D level in blood presented no significant decrease. Also, complete fracture lines involving bi-cortex were observed in all cases based on the radiologic examination, but no periosteal reaction was observed. However, the possibility of nonunion after fatigue fracture cannot be ignored, because most patients did not show any special trauma other than continual sports activities, the fracture occurred in the dominant side in 22 of 23 cases, and there was minor pain during activities.
The fractures mostly occur in adolescent athletes whose growth plates have not closed or have closed recently, usually on the lateral side of the head and the medial side of the base. It is known that these parts are relatively weaker than other parts. 14 Similarly, in most cases discussed in this study, the patients’ growth plates were still open, and only one patient was an adolescent athlete in the whose growth plates have closed recently.
Previous studies have reported that hallux valgus can be the cause of fracture biomechanically, 8,14,15 bowstring effect of extensor hallucis longus tendon and adductor hallucis tendon constantly occurs in the lateral side, causing an avulsion fracture due to the traction and shearing force of medial collateral ligament and abductor hallucis tendon on the medial side of proximal phalanx base.
However, we assessed valgus deformity of great toe at fracture side and contralateral side by simple radiograph in order to confirm the causal relation of the fracture and deformity with consideration for possibility to arise the valgus deformity of great toe by the fracture. As a result in the case of fracture of the proximal phalanx, contralateral valgus deformity was generally less than on fracture side, and HVA and HVIPA were measured normal range, below 15°, except for one case. And postoperative valgus correction in many cases also supports this. Considering this, it was concluded that possibility is more likely to arise valgus deformity of great toe by fracture of the proximal phalanx than by hallux valgus deformity.
An 18-year-old soccer player in one case showed valgus deformity of both great toes had played sports for about 7 years and the growth plates were completely closed at the time of initial visit (case 4). Unlike other cases, the patient was a professional athlete and the growth plate was already closed and considered an exceptional case who showed deformity due to long years of sports activities during the growth stage.
Fracture of proximal phalanx of great toe is generally known for a high risk of nonunion. Yokoe and Kameyama reported that nonunion was observed in 4 of 10 patients with fracture of a proximal phalanx after nonsurgical treatment. 8 In such high-risk cases, we operated by open reduction and internal fixation. As a result, except for a case in the final follow-up, valgus angles were corrected in every case. In this respect, there is a high possibility that intra-articular fracture of the great toe can cause valgus deformity gradually. So it is recommended to perform operative treatment as soon as possible once the fracture occurs.
In one exceptional case, the anatomical reduction was performed with screws, and after 6 months, hallux valgus interphalangeus was observed. To correct valgus deformity, metal removal, auto-tibial bone graft, and K-wire fixation were performed. The temporary fixation at interphalangeal joint was also done using K-wire.
All cases showed clinical bone union at around 6 months after operation. However, radiological nonunion was observed in three cases of one group and the other groups showed radiological bone union in all cases. After that, intermittent splint applying treatment and limitation of active motion were followed. At last, all three cases got a radiologic bone union in 12 months. It seems that the treatment using only K-wire failed to provide sufficient stability due to weaker fixation force compared to the cannulated or headless screw. Therefore, we think that using the cannulated or headless screw would provide greater stability in intra-articular fracture of proximal phalanx of great toe.
Our study’s conclusion is that the fracture of the lateral side of the proximal phalanx head and the medial side of the base is likely to occur by direct trauma of relatively weaker site and valgus deformity of great toe progress gradually. Also, the deformity of great toe may be observed as hallux valgus or hallux valgus interphalangeus according to the site of fracture, and treatment using cannulated screws or headless screws would provide more stability for bone union. Proof that the exact reduction in intra-articular fracture of great toe can correct valgus deformity is also important.
The limitations of this study are small subjects, retrospective study, and relatively short period of sports activities. While a strong point of this study is dealing with many cases of fracture of the proximal phalanx head in addition to more popular fracture on the proximal phalanx base. Also, for the first time, this study analyzes the treatments of and causal relation between valgus deformity of great toe and intra-articular fracture of the proximal phalanx. To get more accurate results, it needs a prospective study with more cases.
Conclusion
Intra-articular fracture of proximal phalanx occurs in patients who have been engaged in sports activities constantly, and hallux valgus mainly arises in the fracture of the medial side of the proximal phalanx base and hallux valgus interphalangeus mainly arises in the fracture of the lateral side of the proximal phalanx head. And anatomical reduction in intra-articular fracture of great toe causes the correction of valgus deformity. So operative cure is recommended in the case of such a fracture.
Footnotes
Declaration of conflicting interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was supported by the Dong-A University’s research fund.