ORIGINAL PAPER

Pulp tissue anchor repair for the zone I flexor tendoninjury: introduction of a new and cost-effective technique

M. A. Hussain & S. Mui & A. Pandya & E. Tan &

A. N. Pandya

Received: 29 December 2011 /Accepted: 24 February 2012 /Published online: 21 April 2012# Springer-Verlag 2012

AbstractBackground Flexor digitorum profundus tendon (FDP)injury in zone I is one of the common findings in thehand examination when a patient presents with a handtrauma. Various repair techniques have been describedin the literature with its own advantages and disadvan-tages. In this article, the senior author describes a newpulp tissue anchor repair for the zone I FDP injuries.Methods After a careful dissection of the proximal end ofthe tendon, a fish-mouth incision is made on the distal pulpof the finger. A modified Kessler stitch is placed in theterminal end of the tendon.Then, the suture is passedthrough the periosteum and the fibrous bands of the pulpusing the wide-bore needle. A knot is secured in the fish-mouth incision, and the skin is closed.Results This technique was used in closed FDP avul-sions (n019), two-stage tendon repairs using palmarislongus (n024), with the remainder being open injuries(n070). There were 18 patients who presented with aflexion contracture at the distal interphalangeal jointlevel and two cases of rupture in zone I divisions.Conclusion The technique described is cost effective asthere is no need for the use of drills, K-wires, suture

anchors or intraoperative imaging. Furthermore, it issimple and quick to perform. The repair is strong, andrisk of infection is minimal as bony cortices are notbreached. Minimal assistance is required, and all thesefactors combine to reduce the cost of the procedure.Level of Evidence: Level IV, therapeutic study.

Keywords Flexor digitorum profundus . Tendon injury .

Zone 1 . Pulp tissue anchor repair

Introduction

Zone I flexor tendon injury is by definition an injury tothe flexor digitorum profundus (FDP), and this can beeither an open or a closed injury. Open injuries may becaused by knives, glass or anything else sharp enough tocause soft tissue disruption. Closed injuries are usuallyan avulsion injury of the FDP that occurs when anactively flexed finger is forcefully hyper-extended at itsDIP joint [1]. This forceful movement pulls the FDPtendon from its insertion on the distal phalanx. Avulsioninjury usually occurs at the site where the tendon insertsonto the bone; the musculotendinous junction is a lesslikely site for avulsion injury due to the structurallystrong tendon link [2]. In patients with systemic inflam-matory conditions, however, intratendinous rupture ismore likely to occur [3–5].

M. A. Hussain (*) : S. Mui :A. Pandya : E. Tan :A. N. PandyaPlastic Surgery Department, Queen Alexandra Hospital,NHS Trust Portsmouth,Portsmouth, UKe-mail: alihussain1976@yahoo.co.uk

Eur J Plast Surg (2013) 36:27–30DOI 10.1007/s00238-012-0713-3

On clinical examination, patients with zone I FDPinjury are unable to actively flex the DIP joint [6].Other clinical findings may include localised tenderness,swelling and erythema. The ring finger most commonlysustains closed avulsion injury of the FDP because theinsertion of its FDP tendon is weaker than the otherdigits [7].

There are five types of avulsion injury of the FDPaccording to Leddy and Packer's classification system[8], and different methods for managing each injurypattern. Closed avulsion injury of the FDP can also beclassified based on the level to which the avulsed ten-don is retracted, along with the presence and size ofany bony avulsion fragment as seen on radiography.This classification, as well as the time since injury, is

important in determining the management plan for theinjury (i.e. one-stage vs two-stage repair).

Technique

We are describing the method with diagrammatic and pho-tographic illustrations with the retrospective audit findingsof 113 cases which senior author has performed in last 14years with 72 cases since 2001.

In this technique, we have used 3/0 ethibond suture toanchor the flexor digitorum profundus tendon to the softpulp tissue, which is illustrated in the diagrammaticrepresentation in Fig 1a, b, c. After a careful dissectionof the proximal end of the tendon, a fish-mouth incisionis made on the distal pulp of the finger as shown in Fig.2a and b. A modified Kessler stitch is placed in theterminal end of the tendon using a 3/0 ethibond suturewith needles at both ends; then, the suture is passedthrough the periosteum and the fibrous bands of the pulpusing the wide-bore needle as shown in Fig. 3a and b. Aknot is secured in the fish-mouth incision, and the skin isclosed with a 5/0 ethilon suture, as illustrated in Fig. 4aand b. To test the repair, the forearm is squeezed, result-ing in flexion at the DIPJ as shown in Fig. 5.

Results

This technique was used in closed FDP avulsions(n019), two-stage tendon repairs using palmaris longus(n024), with the remainder being open injuries (n070).There were eighteen patients who presented with aflexion contracture at the distal interphalangeal jointlevel, and two cases of rupture in Zone I divisions.No infection was seen in the cases performed by thesenior author.

Fig. 2 A wide-bore needle isused to pass the needle throughthe fibrous bands of the pulp

Fig. 1 Diagramatic representation of the technique

28 Eur J Plast Surg (2013) 36:27–30

Discussion

There are several conventional techniques that are currentlyused to repair an injured FDP tendon. Firstly, there is thedorsal button technique. This is performed by drilling aKeith needle from proximal volar to distal dorsal throughthe distal phalanx, out of the nail bed and nail plate, severalmillimetres distal to lunula. Then, two or four strands of 2/0or 3/0 monofilament of an unlocked core stitch are placed inthe FDP tendon terminal end. The paired sutures are thentied over a button [9].

A buttonless fixation technique has also been describedto repair FDP tendon avulsion injuries [10]. This is done byextending a half-Bruner incision into the distal volar skin toexpose the insertion site. Then, two drill holes are madethrough the base of the distal phalanx obliquely from theinsertion of the profundus tendon in a dorsolateral direction.The tendon is secured using a modified Kessler suture. Thissuture is then passed through the two drilled holes and tiedanteriorly. A transosseous internal fixation is thus achievedvia this technique.

The other commonly used method of repairing FDPavulsion injury is the suture anchor technique. Differentsizes of anchor are available for FDP tendon avulsion repairand the size of anchor used is dependent on the dimensionsof the distal phalanx. A pilot hole is created by drilling at a45° angle from distal-volar to proximal-dorsal on the distalphalanx [11]. The tendon is then fixed to the distal phalanx

by placing the anchor into the pilot hole and suturing theterminal end of the tendon with a modified Kesslertechnique.

Combination techniques (i.e. bone anchor-dorsal buttoncombination repair technique) have also been describedwhere there was the need for a stronger repair. All thesetechniques that has been descibed in the professional litera-ture for repair of Zone I FDP injuries, has its own advan-tages and limitations. The use of the dorsal button techniquein avulsion injury of FDP was preferred historically forseveral reasons; it is technically simple, and has beentried and tested with good outcomes reported. The dis-advantages of this technique are nail bed necrosis ordeformity due to pressure from the button, infectiontracking along sutures, the need to protect the pulloutsuture configuration and reliance on direct tendon-to-bone healing within 6 weeks [1]. Also patients need tobe briefed in length pre-operatively about the buttonsticking to the nail for 6 weeks. All of these factorsmake this technique difficult and potentially complicatedin a non-compliant patient.

To overcome the complications encountered in thedorsal button technique, a button less fixation techniquehas also been described using transosseous internal fix-ation [10]. Nail bed complications and patient discom-fort due to the button can be avoided, however risks ofinfection tracking along the sutures remain present withthis technique. Furthermore, drilling the hole distally inan oblique dorsolateral direction is technically challeng-ing, and this technique requires use of intraoperativeimaging.

Recent technological advances have introduced the su-ture anchor technique to our repertoire. This technique isdeemed by many to be superior as it is relatively easy toperform and because the buried fixation within the boneminimizes patient discomfort [11]. However, infection risksare high as a foreign body has been placed within the bone.The suture bone anchor is significantly more expensive thanconventional suture and therefore the cost of performing thisprocedure is considerably higher as compared to the other

Fig. 3 A knot is secured in thefish-mouth incision

Fig. 4 Testing the repair

Eur J Plast Surg (2013) 36:27–30 29

described techniques. Furthermore, it is often not readilyavailable in the emergency situation.

Our technique does not require drills, K-wires, sutureanchors or any intraoperative imaging, and is quick andeasy to perform. The repair is very strong and risk ofinfection is minimal as bony cortices are not breached.Minimal assistance is required and all these factorscombine to reduce the costs involved in the wholeprocedure. The senior author has used this techniquefor 14 years and performed 113 procedures with excel-lent results.

Conflict of interest None.

References

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8. Leddy JP, Packer JW (1977) Avulsion of the profundus tendoninsertion in athletes. J Hand Surg Am 2(1):66–69

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10. Teo TC, Dionyssiou D, Armenio A, Ng D, Skillman J (2009)Anatomical repair of zone 1 flexor tendon injuries. Plast ReconstrSurg 123(2):617–622

11. Schreuder FB, Scougall PJ, Puchert E, Vizesi F, Walsh WR (2006)The effect of mitek anchor insertion angle to attachment of FDPavulsion injuries. J Hand Surg Br 31(3):292–295

Fig. 5 a Dissection of the proximal end of the FDP. b Fish-mouth incision in the distal pulp

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