Outcomes of Chronic Turf Toe Repair in Non-athlete Population: A Retrospective Study

Abstract

Background

Turf toe injuries, though most common in athletes, can also occur in non-athletes. No study exists in the current literature investigating operative outcomes in non-athlete patients with chronic turf toe injury. In this study, we present our outcomes on operatively treated turf toe injuries in non-athletes in the only cohort yet studied.

Methods

Using ICD-10 codes, we assembled a cohort of 12 patients who underwent operative repair of chronic turf toe injury from January 2012 through January 2018 at the investigating institution. These 12 patients were evaluated to determine demographic information, method of injury, length of time from injury to surgery, clinical and radiologic characteristics of the injury, and operative outcomes including mean preoperative and postoperative VAS (Visual Analog Scale) scores, preoperative and postoperative FFI (Foot Function Index) scores, and postoperative complications.

Results

On initial clinical presentation, all 12 patients had local tenderness with associated painful range of motion. Four patients had restricted range of motion, all patients had a positive Lachman test, two had local edema, and eight had hallux valgus deformity. Mean VAS improved from 4.6 (range 2–9) to 1 (range 0–4). Mean FFI improved from 102.5 (range 56–177) to 61.75 (range 23–144). All patients had a negative Lachman test at final follow-up. No patients developed major complications or required revision surgery.

Conclusions

Our study is the first to investigate operative outcomes following chronic turf toe injury in non-athlete patients. Based on our study, surgeons and patients can expect significant improvement in overall pain and function following surgery.

Introduction

Turf toe injury is a sprain or tear of the capsular ligament of the first metatarsophalangeal (MTP) joint, frequently caused by hyperextension of the joint [1–4]. While most of these injuries can be successfully treated nonoperatively, some patients fail conservative management, requiring surgery to restore stability of the joint and continuity of plantar plate structures [5–7]. The indications for surgery in athletes following an acute injury are summarized in Table 1 [4]. No studies exist currently investigating operative outcomes in non-athlete patients with chronic turf toe injury. We present our outcomes on operatively treated turf toe injuries in the largest cohort yet studied.

Table 1.

Indications for operative management [4]

1. Large capsular avulsion

2. Diastasis of bipartite sesamoid

3. Diastasis of sesamoid fracture

4. Retraction of sesamoid

5. Traumatic hallux valgus deformity

6. Vertical instability (positive Lachman test)

7. Loose body

8. Chondral injury

9. Failed conservative treatment

Materials and Methods

Chart Review

Using ICD-10 codes, we assembled a cohort of 12 patients who underwent operative repair of chronic turf toe injury from January 2012 through March 2018 at the investigating institution. Patients were only included in this study if they were greater than 16 years of age, did not participate in collegiate or professional athletics, had an injury requiring operative management, and had a time from injury to surgery of at least 3 months, thus qualifying the injury as chronic. These 12 patients were evaluated to determine demographic information, method of injury, length of time from injury to surgery, clinical and radiologic characteristics of the injury, and operative outcomes, including mean preoperative and postoperative Visual Analog Scale (VAS) scores, mean preoperative and postoperative Foot Function Index (FFI) scores, and postoperative complications. All patients received a foot MRI and radiographs preoperatively to assess the injury and any co-pathologies. All patients were contacted by phone to assess their current Foot Functional Index.

Operative Procedure

After administration of an ankle block, each patient was positioned, draped, and placed in an above ankle Esmarch tourniquet. A 3 cm incision was made on the medial plantar aspect of the first metatarsophalangeal (MTP) joint with subsequent blunt dissection through the subcutaneous tissue. The plantar medial branch of the cutaneous nerve was protected as we completely exposed the capsule of the first MTP joint. Once the first MTP joint was shown to be in anatomic position clinically and radiographically, the medial sesamoid was then examined for arthritic changes or signs of avascular necrosis. If such changes were discovered, a medial sesamoidectomy was performed. If only the distal pole of a bipartite medial sesamoid was found to be involved, then only the distal pole was resected. Due to the chronic nature of these injuries, the plantar plate was, in every case, severely tethered to the base of the proximal phalanx by scar tissue. The scar tissue was resected, and the plantar base of the proximal phalanx was entirely denuded. A 3.5 mm suture anchor was then inserted into the proximal phalanx under the guidance of C-arm and used to reattach the plantar plate to the base of the proximal phalanx with subsequent tightening of the plantar plate. If an osteophyte or chondromalacia of the cartilage over the dorsal aspect of the first metatarsal head was identified, then a cheilectomy or micro-fracture was performed. At this point, the flexor hallucis longus was also thoroughly inspected and repaired necessitated by the presence of tendinosis or tear. After finishing the repair of the plantar plate, the MTP joint was observed in the anatomic position clinically and radiographically.

Next, we turned our attention to correction of the traumatic bunion if one was noted preoperatively. The medial eminence was excised with the micro-saw just medial to the sagittal sulcus. We inserted a suture anchor in the medial aspect of the first metatarsal head, and then used the suture anchor to tighten the medial capsule. If we noted redundant medial capsule just prior to suture anchor placement, a modified L-shaped incision was used to first remove a wedge of capsule at the first MTP joint level prior to suture anchor placement. We then assessed the position of the great toe both clinically and radiographically with the C-arm. After thorough irrigation, the wound was closed by layer.

While still in the operating room, we placed the patient in a toe spica cast to hold the first MTP joint in a neutral position to secure the restoration. We kept the patient non-weight bearing for 2–4 weeks followed by partial weight bearing to full weight bearing in a boot for 6 weeks.

Results

The mean age of the patients in our cohort was 29.6 years (range 16–61 years) and was composed of eight females and four males. The mean time from onset of injury to surgery was 14.63 months (range 2.5–24 months). The average postoperative follow-up time was 6.68 months (range 1.5–19 months).

On initial presentation, patients were evaluated to assess the full extent of injury based on presenting signs and symptoms (Table 2). All 12 patients had local tenderness at the base of the great toe with associated painful range of motion. Of our 12 patients, two (16.7%) had both dorsiflexion and plantarflexion restriction, two (16.7%) had only dorsiflexion restriction, one (8.3%) had plantarflexion restriction, and the remaining seven patients (58.3%) had full range of motion at the time of surgery. Two patients (16.7%) were found to have local edema, and one (8.3%) of these patients had significant ecchymosis at the base of the first metatarsal. All 12 patients (100%) had a positive Lachman test. Eight patients (66.6%) were found to have hallux valgus (Fig. 1); four of which (33.3%) showed radiographic evidence of progression of their hallux valgus from initial evaluation to the time of surgery, as demonstrated by widening intermetatarsal and hallux valgus angles.

Table 2.

Presenting signs and symptoms

Sign or symptom	% present
Local tenderness at the base of the great toe	100
Restricted range of motion	33.3
Positive Lachman test	100
Local edema	16.7
Hallux valgus deformity	66.6

Fig. 1.

Dorsal view MRI of 8-month-old turf toe injury

Our 12 patients can be further stratified according to their injury pattern and concomitant co-pathologies as determined radiologically and intraoperatively (Table 3). All 12 patients experienced thinning, fraying, or tearing of the plantar plate (Figs. 2, 3). Four patients (33.3%) had medial sesamoid edema, while one patient (8.3%) had lateral sesamoid edema. Of these patients with sesamoid edema, two (16.7%) were found to have a bipartite sesamoid and two (16.7%) had a fractured medial sesamoid with nonunion. Two patients (16.7%) developed metatarsal head sesamoid arthrosis due to the chronic nature of their turf toe injury. One patient (8.3%) was also found to have irregularity of the medial sesamoid phalangeal ligament on MRI. One patient (8.3%) had marginal osteophyte and cartilage irregularity at the MTP joint with partial tear and severe tendinosis of the flexor hallucis longus. One patient (8.3%) had a partial tear of the flexor hallucis brevis.

Table 3.

Co-pathologies present

Co-pathology	% present
Sesamoid edema	41.7
Metatarsal head sesamoid arthrosis	16.7
Injury to the medial sesamoid phalangeal ligament	8.7
Severe tendinosis of the flexor hallucis longus	8.7
Partial tear of the flexor hallucis brevis	8.7

Fig. 2.

Anterior/posterior view MRI of 8-month-old turf toe injury

Fig. 3.

Lateral view MRI of 8-month-old turf toe injury

All 12 of the patients included in our cohort underwent repair of the plantar plate. The affected sesamoid was removed in six patients (50%). Nine patients (75%) underwent capsulorrhaphy to correct a bunion with concomitant cheilectomy in five patients (41.7%) and silver osteotomy in two patients (16.7%). The flexor hallucis longus and the flexor hallucis brevis tendons were debrided and repaired in one patient (8.3%) each.

We collected VAS scores from all 12 of our patients preoperatively and postoperatively. Our patients’ mean VAS improved from 4.63 (range 2–9) preoperatively to 1 (range 0–4) postoperatively. We also collected FFI scores from all 12 of our patients preoperatively and 4 of our patients postoperatively. For the four patients who had both preoperative and postoperative FFI scores, the mean FFI score improved from 102.5 (range 56–171) preoperatively to 61.75 (range 23–144) postoperatively. All patients had a negative Lachman test at final follow-up. Eleven of 12 patients (91.7%) had painless ROM on follow-up. No patients developed any major complications, and two patients (16.7%) experienced minor complications (Table 4). One patient (8.3%) had neuritic pain over the medial cutaneous nerve of the great toe, and one patient (8.3%) had a stitch granuloma with exposed suture material that required operative suture removal.

Table 4.

Postoperative complications

Complication	% present
Major complication	0
Revision surgery	0
Neuritic pain	8.7
Stitch granuloma	8.7

Discussion

Turf toe injury is a sprain or tear of the capsular ligamentous structure of the first metatarsophalangeal (MTP) joint [1–4]. Although the mechanism of injury is well understood as it is frequently caused by hyperextension of the joint, there is wide variation in the extent of the structural injury, the symptoms of injury, and the recovery time [1, 2, 4, 8]. The plantar plate is comprised of two sesamoid phalangeal ligaments, the intersesamoidal ligament, and an extension of the plantar aponeurosis. Structural injury may range from a mild sprain of the plantar plate structures to gross tear of the plantar plate with possible fracture of the sesamoids or traumatic diastasis of the bipartite sesamoids [9]. Injuries with a valgus or, less commonly, varus force vector may result in injuries to the medial or lateral collateral ligaments, respectively. It is this variation of injury, coupled with the complexity of the MTP joint, that makes the diagnosis of these injuries challenging and may lead to a delay in recognition of an unstable joint and, subsequently, a prolonged recovery [1, 8, 10].

Turf toe injuries are most common in athletes, typically occurring when a player’s ankle is forcibly plantar flexed while the forefoot remains fixed on the ground, thus driving the great toe dorsally beyond its normal extension arc of motion. In athletes, turf toe can lead to significant chronic problems, including loss of push-off strength, persistent pain, progressive deformity, and joint degeneration [2, 4, 5, 9]. The causal mechanisms of turf toe injury in the non-athlete patient population have not been investigated in the current literature. Presumably, these patients experience a similar mechanism of injury; however, these injuries are incurred during activities of daily living, such as amateur exercise, motor vehicle crashes, or falls. Once the injury is sustained, the natural history of turf toe in non-athlete patients mirrors that of athletes.

The majority of patients will respond to conservative treatment of their turf foe injury. Conservative management typically starts with RICE therapy, oral anti-inflammatory medications [5], and a walking boot/shoe. A short leg cast with a toe spica extension can be beneficial in the early acute phase by immobilizing the joint in slight plantarflexion to remove any tension from the plantar plate structures and by bringing the plantar rupture into close apposition [2, 4, 5, 7, 11]. If symptoms permit, patients should begin a gentle range of motion exercises at 3–5 days from the injury and gradually increase activity as tolerated [4, 5]. Most cases of turf toe can successfully be treated through conservative management; however, some patients fail these measures, requiring operative intervention to restore stability and the anatomy of the plantar plate structures [5–7]. For patients with chronic turf toe injury, one study recommended operative management for patients that develop hallux rigidus, chronic synovitis, progressive hallux valgus, symptomatic degeneration of the MTP joint or persistent inability to perform normal gait due to loss of push-off [8]. The goal of surgery in all patients is to restore normal anatomy, thereby regaining the stability and function of the plantar capsular ligamentous complex of the hallux MTP joint [8].

A few studies have investigated operative outcomes in athletes with turf toe injuries, [12–14] however, no studies exist in the current literature investigating operative outcomes in non-athlete patients with chronic turf toe injury. This paucity of data is likely due to (1) the low incidence of these injuries in non-athletes, and (2) the efficacy of conservative management, which limits the number of patients who ultimately require operative intervention. This study reports clinical outcomes from the largest cohort of non-athlete patients treated operatively for turf toe injury.

Although the vast majority of turf toe injuries occur in athletes due to the drastic increase in force imparted on the capsular ligamentous complex of the hallux MTP during athletic activity [7], these injuries warrant discussion in the non-athlete population due to potentially different associations with demographic variables and clinical outcomes.

There have been multiple guidelines published pertaining to the preoperative evaluation of turf toe injuries. The majority of these combine physical examination with radiographic and imaging studies [10, 15]. Noting the lack of quantitative radiographic guidelines for plantar plate tears [1, 2, 13, 16], Waldrop et al. recently developed a new set of quantitative guidelines for these injuries to assist in the diagnosis and assessment of severity of plantar plate tears [17]. The authors found that an increase of 3 mm from the sesamoids to the proximal phalanx was significantly predictive of severe injury to the plantar plate. In our study, all twelve patients demonstrated thinning, fraying, or tearing of the plantar plate on MRI studies, thus lending credence to the idea that these same quantitative guidelines would likely be effective if employed in the non-athlete patient population.

Various treatment paradigms for management of turf toe injuries have been described in the literature [3, 18, 19]. Van Hal et al. reported that, unlike other types of stress fractures, conservative management of sesamoid fractures was not effective in fracture healing, and all patients in their series ultimately received sesamoidectomy. More recently, Drakos et al. described dividing these injuries into “stable” and “unstable” groups to guide management, with stable injuries defined as a less than 2-mm change in proximal retraction of the sesamoids of the affected first MTP joint as compared to the contralateral on dorsiflexion stress radiographs. The authors suggest conservative treatment for stable injuries (i.e., walking boot, protected weight bearing) or casting for injuries that demonstrated substantial injury to the joint capsule on MRI. For unstable injuries, the authors suggest using aggressive operative intervention with fragment excision and plantar plate repair that may include tendon augmentation. In the present study, all 12 patients received plantar plate reconstruction and 6 underwent sesamoidectomy, providing stronger evidence that plantar plate repair and sesamoidectomy are effective in the treatment of these injuries.

Regardless of the treatment strategy employed in prior studies, the authors consistently report high rates of symptom resolution and low complication rates when treating turf toe injuries [3, 18–20]. These operative outcomes in athlete populations are consistent with those found within the present study of non-athlete patients with chronic turf toe injury. In our cohort, 11 of 12 patients (91.7%) experienced full painless ROM postoperatively, and the mean VAS score improved from 4.6 preoperatively to 1 postoperatively. Furthermore, 0 of 12 patients experienced a major complication and only 2 of 12 patients (16.7%) experienced a minor complication. These results demonstrate the overwhelmingly satisfactory operative outcomes that can be achieved in non-athlete patients with chronic turf toe injury.

The current literature provides limited information regarding concomitant co-pathologies of turf toe injuries that may be found during preoperative radiographic evaluation or intraoperatively. In the current study, five patients (41.7%) had sesamoid edema, two patients (16.7%) had a bipartite sesamoid, two patients (16.7%) had a fractured medial sesamoid with nonunion, two patients (16.7%) had metatarsal head sesamoid arthrosis, one patient (8.3%) had an irregularity of the medial sesamoid phalangeal ligament, one patient (8.3%) had a partial tear of the flexor hallucis longus, and one patient (8.3%) had a partial tear of the flexor hallucis brevis. To achieve the best possible operative outcomes, surgeons need to be aware of and search for these potential co-pathologies to aid in preoperative planning.

This study has a few limitations that warrant discussion. First, this study includes patients treated by a single surgeon at a single institution. Second, statistical comparison testing is desirable but not feasible due to the very low incidence of these injuries in the non-athlete population. Third, due to the retrospective nature of this study, other potential co-pathologies of turf toe injury could not be screened for. Fourth, our study compared preoperative and postoperative VAS scores as a proxy for subjective patient satisfaction. The improvement in mean VAS score is an oft-used measure for this purpose; however, this score does not provide any additional information regarding foot function postoperatively. We also collected preoperative and postoperative FFI scores to further understand patient satisfaction and return to foot function. Though our patients experienced a significant overall improvement in their mean FFI scores (mean 102.5 preoperatively, mean 61.75 postoperatively), this data cannot be used to draw final conclusions due to the relatively low response rate (4/12, 33.3%) to the postoperative questionnaire. Thus, future studies should seek to obtain a better response rate to the FFI to better understand the community ambulators’ postoperative foot function. In the interim, the notable improvement in VAS scores serves as a suitable proxy for patient satisfaction. Finally, our study included patients who underwent surgery as recently as 6 months prior to the collection of this data. Though those patients in the cohort who underwent surgery more recently did not experience any significant early complications, we cannot yet assess whether they may suffer late complications that would not be included in this analysis.

Conclusion

Non-athlete patients treated operatively for chronic turf toe injury that has failed conservative treatment demonstrate excellent clinical outcomes with minimal complications. There are multiple other co-pathologies that may present in this setting, such as injury to the flexor hallucis brevis or flexor hallucis longus, hallux valgus deformity, sesamoid fracture, or metatarsal head sesamoid arthrosis, which may require concomitant procedures at the time of plantar plate repair.

Compliance with Ethical Standards

Conflict of interest

The authors declare that there is no conflict of interest.

Informed consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.