Ortho-Preferred Tracking Pixel
Duke Orthopaedics
presents
Wheeless' Textbook of Orthopaedics

Tibialis Posterior Rupture: FDL Transfer


- PreOp Planning:  
    - tendon transfer is chiefly indicated for stage II tenosynovitis;
    - subtalar joint must demonstrate nearly a full range of inversion;
    - early synovectomy of the tendon sheath not only relieves discomfort but will possibly delay or prevent 
           attenuation or rupture;
    - in presence of correctable hyperpronation, transfer of FDL  tendon to distal posterior tibial tendon stump 
           is considered;
    - if subtalar joint cannot be brought into nearly full inversion because of long-standing deformity, then tendon transfer is contra-indicated;
           - in this case consider subtalar arthrodesis;
    - sping ligament:
           - as pointed out by Gazdag and Cracchiolo (1997), 18 out of 22 posterior tib ruptures had injury to the sping ligament;
           - this ligament courses from the sustentaculum tali to the plantar surface of the navicular, and helps support the head of the talus;

- Surgical Technique:
    - position bump under contralateral hip;
    - begin incision 10 cm proximal to meidal malleolus, continue distally to about 1 cm posterior to medial border of tibia, & end incision 
           just distal to the medial aspect of navicular tuberosity;
    - deep fascia is incised, with care to preserve a portion of the flexor retinaculum, and the TP is exposed, lying close to posterior margin 
           of the tibia;
    - exposure, inspection, and debridement of tibialis posterior:
           - "white sign"
                  - posterior tib will be visible beneath the flexor retinaculum;
                  - abnormally whitened appearance indicates more distal tear;
           - the tendon sheath should be opened in its entirity;
           - if tendon is of normal length, the tendon debridement, tenosynovectomy and sheath resection are performed;
           - if tendon is elongated or appears pathologic, then FDL transfer is required;
                  - most tendons will not have complete rupture, but rather, will have thickening and scarring and often a longitudinal tear 
                         will be present;
                  - complete ruptures tend to occur just distal to medial malleolus;
           - PT tendon is transected leaving a 3 cm stump of tendon attach to the navicular;
                  - this tendon stump may be necessary to repair the spring ligament;  
           - case example: this patient had a degenerative longitudinal rent in the posterior tibialias tendon;
    - spring ligament inspection:
           - at this point in the case, the sping ligament is inspected;
           - the superomedial portion of the spring ligament extends from the sustentaculum tali to the navicular;
           - look for ligament laxity, longitudinal tears, or complete rupture;
           - if the ligament cannot be repaired then use the stump of the PT tendon to augment the reconstruction;
           - also consider spliting the distal posterior tibial segment and achoring one half to the medial malleolus and the other to the 
                  sustentaculum;
    - FDL tendon harvest
           - the FDL sheath is opened distally and is cut distally and is opposed to undersurface of the navicular;
           - the FDL tendon sheath is found directly behind the PT tendon sheath;
           - it is transected as distally as possible (usually as it crosses the FHL tendon);
                  - usually the biggest pitfall of the case is not obtaining enough FDL length;
           - it is not necessary to tenodese the distal FDL tendon stump to the FHL since there are distal interconnections;
           - ref: Risk of Neurovascular Injuries in Flexor Hallucis Longus Tendon Transfers: An Anatomic Cadaver Study 

    - if the PT's sheath is scarred then it is important to leave intact the FDL tendon sheath behind the medial malleolus;
    - alternatively, if the posterior tib sheath is clean, the FDL tendon can be retracted and passed into the PT sheath;
    - drill hole is passed thru navicular tuberosity from dorsal to plantar direction;
    - FDL is brought thru the drill hole from inferior to superior;
    - medial calcaneal sliding osteotomy:
           - ref: The role of osteotomies in the treatment of posterior tibial tendon disorders.
                        Manoli A II, Beals TC, Pomeroy GC. Foot and Ankle Clin.1997;2:309-317.

             
    - optimizing tension of the graft:
           - place anke into slight varus & eqinus, and forefoot adduction;
           - the ankle should not be over tightened;
           - if the navicular is laterally subluxed on the talus, consider shortening the medial capsule prior to tendon suturing;
           - then put tension on FDL tendon and anchor down the suture;
           - if possible, suture the FDL tendon back onto itself, otherwise anchor the FDL to the stump of the PT tendon;

             

    - misc: consider achilles tendon lengthening if necessary;
    - wound closure:
           - if the tibialis posterior muscle belly appears healthy w/ normal 1 cm excursion, then the tendon can be sutured to the FDL 
                  at the level of the meidal malleolus;
           - close the tibialis posterior tendon sheath with care to avoid the N/V bundle;

- Outcomes:
    - in the report by Sammarco et al, 19 consecutive patients underwent FHL (FHL) tendon transfer and medial displacement
           calcaneal osteotomy for the treatment of Stage 2 posterior tibial tendon dysfunction;
           - FHL tendon was utilized for transfer because it approximates the strength of the posterior tibialis muscle and is stronger than 
                   the peroneus brevis muscle;
           - 17 patients returned for follow-up examination, follow-up time 18 months (ave.);
           - AOFAS hindfoot score improved from 62.4/100 to 83.6/100;
           - wtbearing preoperative and postoperative radiographs revealed no statistically significant improvement for the medial 
                  longitudinal arch in measurements of lateral talo-first metatarsal angle, calcaneal pitch, vertical distance from the floor to the 
                  medial cuneiform, or talonavicular coverage angle;
           - three feet had a normal medial longitudinal arch and six feet had a longitudinal arch similar to the opposite side following the procedure;
           - patient satisfaction was high: 10 patients satisfied without reservations, 6 patients satisfied with minor reservations, and 1 dissatisfied;
           - no patient complained of donor deficit from the harvested FHL tendon.
    - in the report by Moseir-LaClair, et al, the authors reviewed 26 patients with 28 pes planovalgus feet secondary to Johnson stage 2
           posterior tibial tendon insufficiency;
           - all were treated with flexor digitorum longus tendon transfer, lateral column lengthening, medial displacementn calcaneal osteotomy, 
                  and heel cord lengthening; mean patient age at surgery was 48.5 years;
           - mean follow-up to date is 5 years;
           - medial cuneiform to fifth metatarsal distance improved from -0.2 mm preoperatively to 7.6 mm postoperatively;
           - similarly, the talonavicular distance improved from 19.4 mm preoperatively to 10.9 postoperatively;
           - there were no nonunions;
           - four feet (14%) displayed radiographic signs of calcaneocuboid arthritis at follow-up;
           - only one was symptomatic requiring calcaneocuboid joint fusion;
           - the double osteotomy technique provides symptomatic relief and lasting correction of the pes planovalgus deformity associated 
                   with stage 2 posterior tibial tendon insufficiency at intermediate follow-up;
    - in the report by Guyton et al, the authors reviewed the results of 26 patients who had undergone the procedure at an average of 32 
           months prior to follow-up (range 12 to 70 months) with particular attention to objective functional parameters;
           - between 1993 and 1998, 26 patients underwent FDL transfer and medial displacement calcaneal osteotomy performed by the senior author;
           - all patients except three could perform a single-leg toe rise at follow-up, a maneuver none could perform preoperatively;
           - of these three, two cases were technical failures with loss of fixation of the FDL transfer early in the postoperative course,
                    ultimately requiring revision procedures including one subtalar fusion;
           - clinically assessed subtalar motion remained 81 +/- 15% of the contralateral side in those patients with unilateral disease;
           - pain relief was rated excellent by 75% and good by 16%;
           - function was felt to be markedly improved by all patients except the three who were unable to perform a single-leg toe rise;
           - median length of time to self-rated maximal medical improvement was 10 months;
    - references:
           - Treatment of stage II posterior tibial tendon dysfunction with flexor hallucis longus transfer and medial displacement calcaneal osteotomy.
           - Intermediate follow-up on the double osteotomy and tendon transfer procedure for stage II posterior tibial tendon insufficiency.



Rupture of the Posterior Tibial Tendon. Evaluation of Injury of the Spring Ligament and Clinical Assessment of Tendon Trasfer and Ligament Repair.

Medial arch strain after medial displacement calcaneal osteotomy: an in vitro study.

Treatment of ruptured posterior tibial tendon with direct repair and FDL tenodesis.
      Shereff MJ. Foot Ankle Clin. 1997;2:281-296.

Adult acquired flatfoot deformity at the talonavicular joint: reconstruction of the spring ligament in an in vitro model.

Flexor digitorum longus transfer and medial displacement calcaneal osteotomy for posterior tibial tendon dysfunction: a middle-term clinical follow-up.




Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Wednesday, April 11, 2012 11:48 am