Abstract
Peroneal tendon subluxation and dislocation occurs when one or both tendons are displaced from the retromalleolar groove during tendon loading. The most common mechanism of displacement is sudden, reflexive contraction of the peroneal muscles either during an acute inversion injury to the dorsiflexed ankle or during forced dorsiflexion of the everted foot. 8 Although conservative therapy may be attempted in acute cases, peroneal tendon subluxation and dislocation has a high rate of recurrence, particularly in athletes. 8 Operative therapy is usually indicated for athletes who have a high level of activity and patients with chronic peroneal subluxation and dislocation, and it generally provides satisfactory outcomes. 16 Many operative treatments have been discussed including tissue transfer,8,16 bone block procedure,14,15 and groove deepening.17,18,20 Because peroneal subluxation and dislocation is frequently associated with injury of the superior peroneal retinaculum (SPR), surgeons prefer direct repair of the attenuated SPR, a procedure first described by Das De and Balasubramaniam in 1985 4 and which, along with subsequent modifications, is associated with good clinical outcomes.1,13,19 Cho et al 2 compared the operative outcome between SPR repair with and without fibular groove deepening for recurrent dislocation of the peroneal tendon, and concluded that both techniques had good outcomes. The authors also concluded for the superiority of the isolated SPR repair to be a faster and simpler technique. However, traditional open surgery needs a skin incision with a length of approximately 6 cm on the posterior lateral region of the ankle, and the scar of the incision comes into contact with the inner surface of the shoe, which leads to the possibility of postoperative scar pain and scar abrasion.
Recent advances in endoscopic surgery, however, allow surgeons to perform minimally invasive surgery for peroneal tendon disorders, and a few reports have introduced endoscopic techniques for SPR repair in cases of peroneal tendon subluxation and dislocation.7,12 The problems with traditional open surgery can be avoided with minimally invasive surgery. In this article, we introduce our tendoscopic surgery technique for the anatomical repair of SPR in cases of peroneal tendon subluxation and dislocation.
Indications
Tendoscopic repair of the SPR is usually indicated for athletes who have a high level of activity and patients with chronic peroneal subluxation and dislocation. With an extra-sheath subluxation and dislocation of the peroneal tendon, which is grade IV in Eckert & Davis classification, 6 it is difficult to reduce the tendon into the groove tendoscopically; therefore, tendoscopic repair of the SPR is recommended for intra-sheath subluxation and dislocation of the peroneal tendons for grade I, II, or III (Table 1).
Indications, Contraindications, Pearls, and Pitfalls of the Presented Technique.
Contraindications
For cases with peroneal tendon injury that need repair or tubularization, tendoscopic surgery cannot be applied because the repair procedure for the injured tendon is impossible using a tendoscope. Furthermore, if the SPR is too attenuated to repair, another open surgery such as bone block procedure, tendon rerouting procedure, and tissue transfer to reinforce the superior peroneal retinaculum should be performed with an open technique (Table 1).
Operative Technique
The operation is performed under general or spinal anesthesia with the patient in the lateral decubitus position with a thigh tourniquet.
The proximal portal is created over the peroneal tendons 3 cm proximal to the tip of the lateral malleolus. After blunt dissection of the subcutaneous tissue (Figure 1), the exposed peroneal tendon sheath is incised longitudinally to the same length as the skin incision. Then, a 2.7-mm arthroscope with a 30° angle is inserted and a distal portal is created with transillumination at the tip of the lateral malleolus to protect the sural nerve (Figure 2, 3).
Detachment of the SPR from the lateral malleolus is confirmed under endoscopic visualization through the proximal portal, which is used mainly as the viewing portal (Figure 4). The probe is then inserted through the distal portal, which is used mainly as the working portal and for inspecting the operative site for concomitant disorders such as tendon tears.
After inspecting the peroneal tendon sheath, the insertion of the detached SPR is debrided using a 3.5-mm motorized shaver introduced through the distal portal to prepare for anchor insertion (Figure 5).
Two suture anchors are inserted into the attachment region of the detached SPR through the distal portal under endoscopic visualization via the proximal portal (Figures 6 and 7).
An 18-gauge needle with 2-0 nylon suture (Figure 8) is introduced through the skin along the posterior part of the distal fibula as a suture lasso to penetrate the SPR under direct endoscopic visualization (Figure 9), and the nylon loop is pulled out from the distal portal with a grasper (Figure 10).
One limb of the suture anchor is placed into the nylon loop outside the skin, and the opposite end of the nylon loop is pulled out through the skin (Figure 11). As a result, the limb of the suture anchor that penetrated the SPR can be removed via the skin. Using the same technique, the other limb of the suture anchor penetrates the SPR and is removed via the skin (Figure 12). Eventually, the 2 pairs of suture anchor limbs that penetrated the SPR are removed via the skin.
These suture anchor limbs are pulled out through subcutaneous tissue, between the skin and the SPR, using mosquito forceps that is inserted into the distal portal, and out of the distal portal (Figure 13).
Each pair of suture limbs is tied with a sliding knot and cut with a suture cutter (Figure 14).
After the procedure, protection of the dislocated peroneal tendons by the repaired SPR is confirmed by endoscopic visualization thorough the proximal portal (Figure 15). Once confirmed, the 2 portals are closed.
Intraoperative photograph showing creation of the proximal portal.
Intraoperative photograph showing transillumination of the sural nerve.
Intraoperative photograph showing creation of the distal portal with transillumination in order to protect the sural nerve from injury.
Tendoscopic view showing detachment of the superior peroneal retinaculum from the lateral malleolus.
Intraoperative photograph (A) and tendoscopic view (B) showing roughening of the attachment of the detached superior peroneal retinaculum using a 3.5-mm motorized shaver.
Endoscopic view (A) and intraoperative photograph (B) showing insertion of a suture anchor into the roughened attachment of the detached superior peroneal retinaculum through the distal portal.
Intraoperative photograph (A) and illustration (B) showing insertion of 2 suture anchors.
Photograph showing construction of the loop as a suture lasso with a 2-0 nylon suture threaded through an 18-gauge needle.
Intraoperative photograph (A) and illustration (B) showing placement of an 18-gauge needle with 2-0 nylon suture through the skin of posterior part of the distal fibula.
Endoscopic view showing grasping of the nylon loop with a grasper.
Intraoperative photograph (A) and illustration (B) showing passing of one limb of the suture anchor through the nylon loop outside the skin.
Illustrations (A and B) showing limbs of the suture outside the skin that penetrate the superior peroneal retinaculum by pulling opposite end of the nylon loop.
Intraoperative photograph (A) and illustration (B) showing pullout of suture anchor limbs through subcutaneous tissue using mosquito forceps.
Intraoperative photograph (A) and illustration (B) showing suture of each pair of limbs with a sliding knot.
Endoscopic view (A) and illustration (B) showing the anatomically repaired superior peroneal retinaculum.
Postoperative Protocol
0-2 weeks: Below-knee weight-bearing cast immobilization is applied for 2 weeks. Weight bearing is allowed without restriction in accordance with patients’ ability. Sutures are removed at 10 to 14 days.
2-6 weeks: Cast is removed at 2 weeks after surgery, and a soft brace is applied for the next 4 weeks. Active range of motion exercise is allowed with the patient wearing a soft brace.
6+ weeks: Running is allowed at 6 weeks after the operation, and return to sports activity is permitted at 10 weeks after the operation.
Complications
Sural nerve injury is a possible complication even though its risk seems to be lower than a traditional open procedure. To avoid this complication, safety measures such as making the proximal portal with a superficial skin incision, then blunt dissection of subcutaneous tissue and penetration of the tendon sheath using a mosquito forceps should be performed. Furthermore, creation of the distal portal with transillumination is an important technique to protect the sural nerve.
The recurrence of peroneal tendon dislocation is another problem. For such cases, we recommend a traditional open procedure for revision surgery to confirm attenuation of the superior peroneal retinaculum, and if the attenuated superior peroneal retinaculum is not sufficient to protect dislocation, another procedure such as a bone block procedure12,13 or groove deepening is used.15,16,18
Results/Discussion
After the open repair of the SPR, the patient can begin weight bearing at 4 to 6 weeks and return to activity at 12 months after surgery. Because of the fact that the majority of the SPR is left intact, our postoperative protocol permits weight bearing 2 weeks earlier than that of an open technique. We have performed this surgery on 5 patients, which we have followed up for greater than 6 months. In this small group, there were no complications including recurrent subluxation after surgery. Although the number is small and the follow-up is short, the authors feel this minimally invasive technique may accelerate the healing process and it may allow the patient to return earlier to their athletic activity.
Several operative procedures have been reported for recurrent dislocation of the peroneal tendon, including reattachment of the SPR,4,5,7,8 bone block procedures,14,15 tissue transfer procedures,8,16 and groove deepening.17–19 Although no single procedure has been established as the gold standard, reattachment of the SPR seems to be favored by many surgeons for cases with sufficient quality of the SPR because this procedure can reconstruct normal anatomy around the lateral malleolus.
In 1985, Das De and Balasubramaniam reported successful outcomes in 7 patients who underwent anatomical reattachment of a detached SPR and fibular periosteum. 4 Their procedure included incision of the SPR, obliteration of the false pouch, and closing of the incision in the retinaculum. Subsequent modifications of their technique have produced good clinical outcomes,1,13,19 yet a 4- to 10-cm skin incision is required along the peroneal tendons, which can result in excessive scar formation and operative complications such as sural nerve injury. 10
Recent advances in minimally invasive endoscopic treatments in foot and ankle surgery have led to tendoscopy of the peroneal tendon, and this procedure has been used for peroneal disorders such as tenosynovitis, low-lying muscle belly of the peroneus brevis, partial tears of the peroneal tendons, and intra-sheath subluxation or recurrent dislocation of the peroneal tendon.3,9,11,18,20 To date, only 2 reports have introduced endoscopic techniques for peroneal retinaculum repair in cases of recurrent subluxation of the peroneal tendon.7,12 The first technique for repair of the SPR was reported by Lui in 2006. 12 His procedure uses 3 suture anchors under endoscopic visualization with the distal portal positioned just distal to the lateral malleolus and the proximal portal positioned at the proximal end of the retinaculum. 10 Piercing of the anchor sutures into the retinaculum is achieved using a needle with sutures in an inside-out manner that is inserted thorough the portals, and the sutures are retrieved at the surface of the retinaculum by pulling them through the skin wound. 10 However, because the needle is inserted into the subcutaneous tissue in a blind manner, the procedure carries a risk of entrapping the sural nerve posterior to the distal fibula where the nerve runs approximately 19 mm from the lateral border of the Achilles tendon. 4 The second technique, reported by Guillo and Calder in 2013, involves repair of the retinaculum in recurrent peroneal tendon dislocation. 7 Although their technique involves proximal and distal portals for peroneal tendoscopy, a third incision is needed to insert the anchors because the distal portal is too far (3 cm distal) to the lateral malleolus. 7
In the present technique, the proximal portal is created over the peroneal tendons 3 cm proximal to the tip of the lateral malleolus. In this region, the sural nerve runs far from the distal fibula and is therefore less likely to be injured. On the other hand, the sural nerve may be injured when the distal portal is made because it runs close to the lateral malleolus; however, this risk can be minimized by the transillumination technique. The lateral portal at the tip of the lateral malleolus makes not only debridement of the SPR attachment possible but also insertion of suture anchors without the need for another incision. The present procedure also avoids entrapment of the sural nerve when the suture anchor limbs are tied.
Further study with a larger study population followed over the long term is necessary to establish the present procedure for routine use in peroneal tendon subluxation and dislocation repair. Nevertheless, the minimally invasive nature of the present tendoscopic approach has advantages over conventional open surgery.
Summary
We introduced our tendoscopic surgery technique for the anatomical repair of the SPR in cases of peroneal tendon subluxation and dislocation. The low invasiveness of the present tendoscopic approach has advantages over conventional open surgery.
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) received no financial support for the research, authorship, and/or publication of this article.